flexible substrate

Southampton University, p16 University of Cincinnati, p18 DNP, p24 iRex Technologies, p45

Letter from the publisher: e-Skins… by Mark Fihn 2

News from around the world 3

SID Display Week Symposium 2009, June 2-5, San Antonio, Texas OLEDs highlight Display Week by Joe Runde 36 Pictorial Summary of Flexible Displays at SID photos by Jurgen Daniel 38 Summaries of conference proceedings by Phillip Hill 42

Smart Fabrics Conference, March 10-12, 2009, Rome, Italy 52 Phillip Hill covers presentations from Clothing Plus, Atelier Fede, EU Commission, CeNTI, Ohmatex, University of Pisa (x2), Dublin City University, and TITV

Flexible Electronics & Displays Conference, February 2-5, Phoenix, Arizona 58 Phillip Hill covers presentations from DisplaySearch, Nerac, HelioVolt, Universal Display Corporation, GSI Technologies, Philips, Renata Batteries, and PVI

OLEDs World Summit, November 10-12, 2008, La Jolla, California 64

Plastic Electronics Conference and Showcase, October 28-29, Berlin, Germany 68

Silicon Valley Photovoltaics Society (SVPVS) by Jurgen Daniel 76

Cost reduction advances for manufacturing flexible displays and electronics by Abbie Gregg 78

ITO Market Opportunities: Liner Notes From NanoMarkets' Webinar by Lawrence Gasman 85

Flexible printed LCDs by Peter Harrop 88

e-Paper Display Technology and Market by Sarah Han 92

The Last Word: Let there be light! by Chris Williams 100

Display Industry Calendar 101

The Flexible Substrate is focused on bringing news and commentary about the activities of the companies and

technologies related to the development of flexible substrates for the displays industry. The Flexible Substrate is published electronically 10 times annually by Veritas et Visus, 3305 Chelsea Place, Temple, Texas, USA, 76502. Phone: +1 254 791 0603. http://www.veritasetvisus.com

Publisher & Editor-in-Chief Mark Fihn [email protected] Managing Editor Phillip Hill [email protected] Contributors: Jurgen Daniel, Lawrence Gasman, Abbie Gregg, Sarah Han, Peter Harrop,

Joe Runde, and Chris Williams

Subscription rate: US$47.99 annually. Single issues: US$7.99 each. Hard copy subscriptions are available upon request, at a rate based on location and mailing method. Copyright 2009 by Veritas et Visus. All rights reserved. Veritas et Visus disclaims any proprietary interest in the trademarks or names of others.

Flexible Substrate Veritas et Visus June 2009 Vol 4 No 9/10

Veritas et Visus Flexible Substrate June 2009

2

e-Skins…

by Mark Fihn

We’ve written about e-Skins before. We’ve even showcased them during public presentations. But it wasn’t until I actually saw Kent Display’s demonstration of e-Skins at SID in San Antonio earlier this month that I realized just how important this development really is…

Kent’s e-Skins are film laminates 65 microns thick with cholesteric liquid crystal technology inside. Color can be changed on command, and power is utilized only during the color shift process. Once the color is in full display, the electronic skin uses no power whatsoever to maintain the color. The skin can be cut into any desired shape and made to conform to the surface of a personal electronic device. The company’s first generation e-Skins are available in eight different colors. The color can be changed in response to an action taken by the user, (such as pressing a button). But the e-Skin can also change color based on some other thing – like identifying the caller on a cell-phone or as a reminder for a meeting.

In May, Kent announced a $4.9 million award from the Ohio Third Frontier Commission’s Research Commercialization Program. The award is being used to develop e-Skins and other cholesteric LCD products. Kent Displays’ program collaborators include plastic substrate producer DuPont Teijin Films and electronic chip designer Solomon Systech, as well as Kent State University and the University of Akron. Specifically, the support from Ohio Third Frontier will enable the company to develop numerous Reflex electronic skin advancements, such as performance (optical, environmental, durability), size, conformability (complex shapes) and electronics (conductivity, miniaturization). The funding also will be used to refine and optimize the roll-to-roll production process.

Electronic skin technology offers brands and manufacturers new ways to personalize their products by controlling the surface color and even configuring icons and/or alphanumeric characters. A broader color gamut and fixed patterns will also be available as a result of the grant in addition to skins for laptops and electronic logos. Currently, the size of the skins is limited due to the size of Kent’s web, but they are creating a bigger roll-to-roll process that will enable e-Skins on larger devices.

I think this technology is an enormous market changer. Today, the world of displays is primarily focused on beautiful, high-resolution, full-motion video targeted at a handful of consumer and information technology devices. The advent of single-pixel e-Skin technology shifts the world of displays to a much broader range of applications. In fact, almost any surface can be considered as being appropriate for an e-Skin. Not just cell phones and notebook PCs looking for a way to differentiate, but so many devices can benefit from such customization. Imagine the use of some advanced solutions so you can change the color of your car or the siding of your house! St. Patrick’s Day – your house turns green; Valentine’s Day it’s red; and when the temperature is high, you can reflect the sun’s heat with a silver color – or mid-winter you can attract heat with a black color.

My imagination isn’t broad enough to anticipate the impact of e-Skin technologies – but I am quite certain this technology will change the world in ways we can only begin to imagine, perhaps more significant than the advances of the display industry as a whole in the past couple of decades…


3

News from around the world compiled by Phillip Hill and Mark Fihn

Prime View International reaches agreement to acquire E Ink Prime View International, a Taiwanese small and medium display provider and the world’s highest volume supplier of e-paper display modules, announced that it has signed a definitive agreement to acquire E Ink Corporation of the US, the leader in electronic paper display materials and intellectual property, for approximately $215 million. The new company will expand capacity and develop improvements for e-paper display screens. The e-paper display module market will grow to over $3 billion by 2013. This market will see further growth with the emergence of color displays and flexible displays, serving e-book/e-textbook, e-newspaper/e-magazine and e-document markets. Currently, electrophoretic display technology has more than 90% market share in the overall e-paper displays, and E Ink is the #1 supplier of electrophoretic materials.

The market for electronic book devices such as the Sony Reader and Amazon Kindle is forecasted to grow from 1.1 million units in 2008 to 20 million units in 2012, a cumulative annual growth rate of 105% over the four-year period. PVI and E Ink enabled this market starting in 2005 and they have been the display market leaders since. E Ink and PVI currently support nearly 20 e-book manufacturers worldwide. In addition to electronic books, E Ink’s Vizplex imaging film is used in cell phones, signage, smart cards, memory devices, and battery indicators. E Ink sales were $18M in the first quarter of 2009, up 157% over the same quarter in 2008. E Ink’s technology is currently commercially available in the following e-books: Cybook Gen 3 by Bookeen, Digital Reader 1000S by iRex, eSlick by Foxit, EZ Reader by AstakHandyBOOK N516 by Hanvon, Hanlin eReader V3 by Tianjin Jinke Electronics, Hanlin eReader V8 by Tianjin Jinke Electronics, iLiad 2nd Edition by iRex, Kindle 2 by Amazon, NUUT from Neolux, Reader Digital Book PRS-505 by Sony, Reader Digital Book PRS-700 by Sony, STAReBOOK STK-101 by Staretek, SURF segmented display brand, and Alias 2 phone by Samsung.

The deal is the culmination of a transformation at PVI over the past four years to focus on electronic paper displays. In 2005, PVI acquired the e-paper business of Philips Electronics and partnered with E Ink to provide displays for electronic books including the Sony Reader and the Amazon Kindle 2 and Kindle DX. PVI also invested heavily in dedicated driver chips and touch screens for e-paper, as well as flexible displays, which will be marketed later this year. In 2008, PVI bought a 74% stake of Hydis Technologies of Korea, quadrupling capacity for the transistor backplanes used in e-paper.

With the merger, PVI gains substantial intellectual property and employee talent, while securing supply of a critical component during the rapid growth phase of the market, and adding alliances and relationships across the e-paper and flexible display industry. E Ink will continue to supply its products across the display industry and will have access to increased operating funds to boost production and accelerate new technology and product developments. PVI will finance the acquisition with an equity placement and a convertible bond offering led by Taiwanese securities firm KGI. The transaction is subject to shareholder and customary regulatory approval and is expected to close in the fourth quarter of 2009. Since its inception, E Ink has collaborated with a wide range of partners to develop a global ecosystem for electronic paper displays. E Ink also amassed a portfolio of hundreds of patent applications, including 150 issued in the United States. IEEE Spectrum ranked E Ink’s patent portfolio as number three worldwide for computer peripherals and storage. http://www.eink.com

NEC Electronics America showcases new e-paper technology NEC Electronics America showcased a new electronic paper module at SID. Developed by NEC LCD Technologies, it is a 13.8-inch module, A4 international standard paper size. Employing a microcapsule electrophoresis system, the e-paper module provides higher visibility and better grayscale gradation when compared to most printed newspapers. The module leverages NEC LCD Technologies’ experience and proprietary advancements with TFT active-matrix LCDs to secure 16-step grayscale and white reflectivity of 43% and a contrast ratio of 10:1. http://www.am.necel.com/display/


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E Ink announces large format display in its electronic prototype kit E Ink Corporation announced that it has enhanced its lineup of AM-300 EPD Prototype Kits by adding a 9.7-inch display to its suite of offerings, enabling development across a wider range of application sizes. This high-resolution, large-size display comes at a time when more companies are turning to EPDs for larger displays for new content delivery, including newspapers, textbooks, notepads, and business documents. With a resolution of 150ppi and the capability of displaying multiple shades of gray, the 9.7-inch diagonal display has the clarity of newsprint. Once updated, the display image remains visible without energy, which reduces system power consumption by up to 90% compared to traditional LCDs. This third generation, high-resolution developer kit also contains a graphical electronic paper display with pen input. The Broadsheet AM300 prototype kit is a straightforward and easy way to start working with E Ink technology. The Broadsheet kit enables customers to quickly prototype and develop next generation e-paper products. In addition to the display module, the kit also includes a Linux x86 operating environment, E Ink API software for Broadsheet, various sample images, open source software drivers and applications including support for MMC cards, Bluetooth, and USB. http://www.eink.com

ZBD gains traction in US e-paper market for retail solutions ZBD announced that three US-based retailers are set to pilot its electronic shelf label solution (epop) during Q2 2009. ZBD has already enjoyed considerable European success with retailers including SISA, EMT (a TeliaSonera subsidiary), Tesco and others, implementing its e-paper solution. ZBD’s e-paper for retail solution offers significant advantages over paper and old generation ESL counterparts with ultra low-power displays that eliminate the need for paper and printing, enabling retailers to make centralized price changes quickly and easily. They have a minimum 5-year battery life, and 10-year option available. Zero infrastructure requirements enable retailers to demonstrate a very low total cost of ownership making the business case very positive. http://www.zbd.co.uk

HP enables new field of flexible electronics with reflective display technology HP announced the launch of a new display technology for the personalization of consumer electronics products. Electronic Skins, or eSkins, is a flexible reflective color film that can be applied to a variety of devices – including mobile phones, digital cameras, MP3 players, netbooks and notebooks. eSkins also can reflectively display icons and alphanumeric characters. HP eSkins technology offers brand manufacturers new ways to personalize their products with an electronically controlled color surface created using HP’s roll-to-roll manufacturing platform. Designed to make fine-scale circuitry on plastic substrates, the platform processes flexible screens in rolls rather than individual sheets, offering the potential for more cost-effective manufacturing. This new device architecture is compatible with roll-to-roll plastic circuits that can be combined with proprietary, electrically controllable “inks” to achieve print-like color performance, as well as transparency. Using a technology similar to color printing, HP is developing the capability to produce specific “ink” colors within the Pantone Matching System range. The print-quality colors have visibility in direct sunlight and can electronically shift into a transparent state, revealing the surface below the eSkin. http://www.hp.com/

E Ink’s new 9.7-inch display is designed for newspapers, textbooks, notepads and

business documents

HP Electronic Skins, or eSkins, is a flexible reflective color film that can be applied to a variety of consumer electronic devices

for product personalization


5

Amazon announces new Kindle e-book reader Amazon has announced an enlarged Kindle e-book reader, aimed at students and those whose reading extends to documents and textbooks. Larger than the Kindle 2, the DX comes with a screen slightly less than 25cm, (compared to the 15.2cm of the existing model), but has a QWERTY keyboard at the bottom to allow annotation without having to provide a touch screen. The resolution is 1200x824 with 16 shades of gray, and is priced at $489. It comes equipped with a connection to Amazon’s Whispernet service – based on Sprint’s CDMA network – thus limiting it to the US market, but enabling the newspaper and magazine subscriptions, which were supposed to be the revenue generator for the service. http://www.amazon.com

Samsung unfolds phone with E Ink panel Samsung has put an E Ink panel to use as a keyboard on its latest phone. The Alias 2 – successor to Samsung’s 2007 Alias – is described as a dual-hinge messaging phone with a convenient E Ink transforming keypad. According to Samsung, the technology allows the phone’s keypad to change according to what you’re using the phone for. Hold it vertically and numerical keys will be displayed. Switch the phone to a horizontal position and a full Qwerty layout appears that can also change to numeric with symbols. The Alias 2’s main display is a 2.6-inch, 240x320 TFT. The phone has a second screen on the outside. The Alias 2 is available now in North America for roughly $80. http://www.samsung.com/

Plastic Logic demonstrates latest e-reader ahead of launch next year Plastic Logic has demonstrated a touch-screen reader designed to compete with Amazon’s Kindle DX. It will launch it next year. Although that will leave the Kindle DX (which has a similar form factor) six unopposed months on the market, Plastic Logic seems to have some features that could tip the scales. These include a touch screen, a tabbed interface for managing recent content, and the ability to natively display a variety of office content, such as Excel and PowerPoint documents. It will also offer WiFi connectivity in addition to 3G. Plastic Logic stressed at the demonstration that its device was aimed mainly at the business community. One content provider for Plastic Logic’s consumer market, however, could be Google. Google is in the process of reaching a settlement with the publishers and other copyright holders that sued it over its book-scanning activities. That settlement would turn Google into a book retailer, selling copies of out-of-print books that it has digitized, and turning a share of the proceeds over to an independent body that will compensate the rights holders. Google has been looking to win over publishers that are frustrated by the conditions that Amazon sets for getting content onto the Kindle store. Under Amazon’s conditions, publishers have little say over the price of the electronic form of the book, and those copies will only be readable on devices sanctioned by Amazon. Google already has made scanned books available for the Sony Reader. http://www.plasticlogic.com/

Amazon’s Kindle DX has a 9.7-inch display and holds up to 3,500 books, periodicals and documents. The center image shows Samsung’s Alias 2 which has a morphing E Ink keyboard. On the right, Plastic Logic CEO Richard Archuleta at the May 27

Wall Street Journal D7 event


6

Interead and Cybook announce mini e-book readers Two companies have announced cut-down e-book readers. British company Interead launched its Cool-er reader on 27 May, while French CyBook revealed its intention to launch the CyBook Opus in June this year, both devices offering e-ink displays. Interead’s device is 183x117mm and slightly over 10mm thick, which compares to the Kindle’s current 203x135mm with similar thickness though both devices have the same sized screen. While Amazon’s Kindle has a keyboard, speakers and a 3G telephone built into it, and Sony’s reader will play back MP3s, these next-generation e-book readers are designed to read books and PDF documents, and nothing else. CyBooks’ Opus has a higher resolution (200dpi) and one-handed operation, as well as being “pocket sized”. http://www.interead.co.uk/ http://www.bookeen.com/

German start-up txtr launches 6.0-inch e-reader A German start-up, txtr, based in Berlin, have a new e-book reader that is due to hit the German market in the third quarter of 2009. The txtr reader is based on E Ink technology having a 6-inch electronic ink screen that works by aligning black and white pigment particles in an electric field and does not need a backlight. In comparison to the existing e-readers in the market, this one comes with several advantages, the company says. The new display controller allows faster rendering of pages and because of its power-management, a single charge will last for many days of usage. In addition to that, the txtr reader has a novel user interface that allows one hand operation over the capacitive touch slider, and, detecting device orientation with a 3D acceleration sensor, it is automatically aligned for portrait, landscape and left-handed mode. Supporting different document formats, like PDF and HTML, many different documents can be stored on the implemented 8GB SD memory card. It comes with a wireless mobile connection via 3 G/GPRS, with which one can connect to the online platform txtr.com and manage, store and secure or share documents and publications. On top of that, it offers support for audio via a Bluetooth headset and connection to PC via USB and WiFi. http://www.txtr.com

Samsung and LG to cooperate on OLED deposition R&D Samsung Electronics and LG Display will launch joint research and development for LCD panel equipment. The Korea Display Industry Association announced that the two companies agreed to co-develop OLED deposition equipment this year, after cooperating on manufacturing digital exposure equipment last year. The OLED deposition equipment serves an important role in making LCD panels. Samsung and LG will expand their cooperation in R&D to next-generation display processing technology and source technology for core materials.


7

NanoMarkets brings out report on e-paper market opportunities The company says much has happened in the e-paper space since NanoMarkets last report on this topic in 2008. Most notably the arrival of Amazon’s Kindle book reader has turned e-paper into a near-mass-market technology for the first time. This success raises a lot of issues. E-paper has now become identified with E Ink's electrophoretic technology. This report analyzes the new market environment for e-paper and answers these questions. It also looks at the many challenges that e-paper still faces. Although e-paper has become strongly identified with the concept of flexible displays, the first displays are at best foldable; certainly a long way from the rollable displays that futurists have discussed. Then there is the question of color and how far the e-paper market can evolve in a world in which people expect color from displays. http://www.nanomarkets.net

Displaybank projects e-paper market to soar to $2.1 billion by 2015 The flexible display market, that expects applications in concepts of e-newspapers, e-magazines, and e-books, is focusing firstly on the e-paper display. In addition, the market expects various applications not only as bulletin board-use displays such as interior/exterior-use advertisement boards, but also as a mobile communication device. Currently, Taiwan-based PVI and Korea-based LG Display are manufacturing e-paper display products utilizing glass substrates. Various companies including Amazon and Sony have launched e-books using such display. However, a genuine flexible e-paper display using flexible substrates has not yet been produced. LG Display is expected to be the first maker to produce a flexible e-paper display. The company is developing a display using metal foil substrates through collaboration with E Ink based on a-Si TFT technology and is planning to manufacture 11.5-inch flexible display products for the US-based Hearst Corporation in e-magazine format. Displaybank projects the e-paper market to grow from $70 million in 2008 to $2.1 billion in 2015 and $7 billion by 2020 – representing a compound annual growth rate (CAGR) of approximately 47%. Displaybank also projects the e-book market to comprise 50% of the total e-paper market during that same period – growing from $35 million in 2008 to $1.1 billion in 2015 and $3.4 billion by 2020 – with the greatest regional demand coming from the US. These and other findings are disclosed in Displaybank’s newly published e-Paper Display Technology and Market Forecast Report. http://www.displaybank.com

FlexTech Alliance issues inaugural report assessing the flexible solid-state lighting industry The FlexTech Alliance, focused on developing the electronic display and the flexible, printed electronics industry supply chain, announced the release of its first-ever market report of this type, entitled “Flexible Solid State Lighting: Technology, Manufacturing, and Market Assessment”. This 329-page special report provides an in-depth technology overview of the latest advancements and the emerging market opportunities for print-based, flexible, solid-state lighting (SSL).Experts agree that new lighting technologies are needed to promote energy efficiency and help reduce the emission of green house gases. Introduction of LED and organic LED light sources can contribute to accomplishing these goals because of their high efficiency conversion of electricity to visible light. With new SSL technologies, novel form factors can extend and expand lighting applications. It is in this space that print-based, flexible, SSL technologies are poised to enter and change the market place. The FlexTech report aims to fulfill a market need for a complete resource defining the changing technology landscape and emerging market opportunities for this important product evolution. http://www.flextech.org


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NanoMarkets report shows where thin-film batteries will generate revenues NanoMarkets announced the release of “Thin-Film Batteries: Current and Future Markets 2009-2016”. The report contains the latest analysis and market projections from NanoMarkets’ ongoing research program in thin battery markets. A key finding is that thin-film batteries have come a long way since NanoMarkets’ previous report on this topic as more than four million thin-film batteries will ship in 2009 alone. In addition, thin-film batteries are being designed in as storage devices for small photovoltaic or thermoelectric systems to create ultra-long-lived power sources for medical devices, sensors and watches: applications where battery replacement is expensive or difficult to achieve. NanoMarkets’ analysis suggests that cumulative revenues from thin-film batteries will reach more than $1 billion in 2016 with almost 60% of this coming from two applications: sensors and smart cards. Smart cards are highly suited to thin battery technology, because cards equipped with standard coin batteries do not fit easily in wallets or card readers. NanoMarkets also envisions thin-film batteries playing a key role in powering distributed sensors and sees these type of batteries being the perfect power source for large-area flexible sensor arrays which NanoMarkets believes will rapidly penetration military, medical, computing, and environmental markets. By 2016, the value of products shipping with thin film batteries in them will reach almost $3 billion. Nonetheless, NanoMarkets notes that for TF batteries to fulfill its promise, this new technology will need more investment. The firm notes that many of the firms with interesting technologies in this space are under-funded and only Power Solutions and Solicore have raised substantial money in the recent past. Raising new funds to bring thin-film battery products to market in the current climate will be a major challenge and could slow the market’s overall development. http://www.nanomarkets.net

DisplaySearch forecasts worldwide OLED revenues to reach $5.5B by 2015 In the Q1’09 Quarterly OLED Shipment and Forecast Report, DisplaySearch forecasts the total OLED display market will grow to $5.5 billion by 2015, from $0.6 billion in 2008, with a CAGR of 37%. Currently, this growth is being driven by the adoption of active matrix OLED displays for the primary display in mobile phones and portable media players. Expansion of AMOLED manufacturing capacity will enable production of larger displays for mini-notebook and notebook PCs, desktop monitors and larger TVs. DisplaySearch forecasts that in 2015, TV will pass mobile phone main display to become the highest-revenue application at $1.92 billion. DisplaySearch also reported that worldwide OLED display revenue in Q4’08 was $156 million, an increase of 17% Q/Q. OLED revenues for FY2008 reached $615 million, a 24% increase Y/Y. PMOLED had a weak Q4’08, caused by slowing shipments of monochrome and area color OLED. AMOLED experienced a strong quarter, driven by demand for mobile phone main displays, as Nokia, Samsung Electronics and Sony Ericsson heavily promoted AMOLED mobile phones in early 2009. Samsung SDI – whose OLED group merged with Samsung Electronics’ mobile display business to form Samsung Mobile Display (SMD) in January 2009 – had a strong Q4’08. As a result, SMD took the #1 position in shipments with a 31% share, passing RiTdisplay. SMD has been the leader in total OLED revenues for several quarters thanks to its AMOLED shipments. http://www.displaysearch.com/

OLED display revenue forecast


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UK’s Printable Electronics Technology Centre purchases Optomec aerosol jet deposition system Optomec announced that the company’s aerosol jet deposition system has been selected to be part of the PETEC (Printable Electronics Technology Centre) facility. The aerosol jet system, which will be installed at PETEC’s location in County Durham, England, will be primarily used to prototype organic thin film transistors (OTFTs). The system will be located in a Class 100 clean room that contains process equipment for 300mm panel fabrication on glass or flex. The system is one of the items of equipment purchased under the LACE project (Large Area Coating Equipment), and is part financed by the European Union’s ERDF Competitiveness Programme 2007-13. PETEC’s LACE project has secured a total of £2M ERDF investment through regional development agency One North East. The ERDF program is bringing over £250M into the North East to support innovation, enterprise and business support across the region. PETEC is a new design, development and prototyping facility that has brought together leading experts in printable and plastic electronics to help industrial and academic clients bring products to market quickly, cost-effectively and with minimal risk. PETEC’s role is to drive product innovation through all the necessary stages of development, including concept, design, materials formulation, prototyping and fabrication. These functions are supported by a range of application development, testing, validation, process development, and optimization services. Several European-based companies are already using the PETEC facilities to test and develop their new organic electronic prototypes. The aerosol jet system is ideally suited to be part of the PETEC facility because the technology is able to print the fundamental building blocks for printed electronics. The technology is most suited to printing the challenging fine resolution features of the source and drain electrodes in TFTs, in addition to the active channel and other material layers in these electronic device structures. These materials can be combined and layered to make more complex devices and circuits. The ability to print fine features (<10 microns) and work at room temperatures without vacuum processing means the process is an enabling technology for many emerging printed and large area applications. http://www.ukpetec.com

OE-A unveils demonstrators on organic and printed electronics future The new, expanded version of the Organic Electronics Association (OE-A) Roadmap for organic and printed electronics provides answers to the following questions. Where do organic and printed electronics stand? Which applications will be launched over the next several years? Which production processes and materials are needed? Which technological hurdles need to be overcome? Initial products based on organic electronics – thin, light-weight, flexible, and inexpensive to produce – are already on the market. “Organic electronics you can touch” is made possible by the new OE-A brochure. Every copy includes a set of functional organic electronic components as a give-away, such as various printed displays, RFID-tags, switches, batteries and transistor structures. Furthermore, six additional demonstrators in which a number of components are combined on flexible plastic and paper substrates have been introduced. The following OE-A members collaborated on these projects: Acreo, Agfa, CEA, COPACO, DuPont Teijin Films, Felix Schoeller, Fraunhofer IAP, FUJIFILM Dimatix, GSI Technologies, H.C. Starck Clevios, HDM-Stuttgart, ITRI, Leonhard Kurz Stiftung, Mitsubishi Polyester Film, M-Solv, NTERA, Plextronics, PolyIC, Schreiner Group and VARTA Microbattery. http://www.oe-a.org

Insert of the new OE-A brochure with functional printed electronic components


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OE-A releases new roadmap for organic and printed electronics “The market for organic and printed electronics will grow to a multi-billion Euro market in the next ten years“, said Wolfgang Mildner, Chairman of the Organic Electronics Association (OE-A) and Managing Director, PolyIC GmbH & Co. KG, at the OE-A press conference on the occasion of the grand opening of the new conference and exhibition, LOPE-C – Large-area, Organic and Printed Electronics Convention, in late June in Frankfurt, Germany. The OE-A’s third OE-A Roadmap illustrates which applications are already possible today, and gives an outlook on future product generations through the year 2025. Organic photovoltaics, flexible displays, and OLED-lighting as well as data storage devices and circuits, e.g. for RFID-tags (radio frequency identification), were identified as the largest areas for growth in the medium term. http://www.oe-a.org


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FlexTech Alliance announces dates for 2010 Flexible Electronics and Displays Conference The FlexTech Alliance announced the dates for its 9th annual Flexible Electronics and Displays Conference, to be held in Phoenix, Ariz., February 1-4, 2010. Abbie Gregg of AGI, Inc., is joined by new conference co-chairs Keith Rollins of DuPont Teijin Films and Mike Idacavage of Cytec Industries, Inc., to round out the team who will lead this annual event. Working in tandem with a diverse team of advisors, the conference committee expects to attract more than 150 presenters at the 9th annual conference next year. The Call for Papers seeks abstracts addressing technical and business issues, advancements impacting the flexible electronics field, and areas where displays are a key driver. Topic areas of interest include flexible, printed electronics manufacturing, photovoltaics, solid-state lighting, medical devices, RFID, sensors and flexible displays. http://www.flextech.org.

NHK exhibits flexible OLED display NHK’s flexible OLED panel can display video at a frame frequency of 60Hz. The luminance of partner STRL’s flexible OLED panel was doubled by improving the production method for the organic TFT arrays used for driving and selecting pixels. And it has a higher display uniformity. The 5.8-inch flexible OLED panel features a low drive voltage of 5-15V, a resolution of 213x120, a frame frequency of 60Hz and 8-bit gradation. Its luminance was enhanced by using a phosphorescent substance as a light emitting material. The panel is between 0.3 and 0.4mm thick. http://jp/nhkworld

IGNIS Innovation demonstrates latest achievements in AdMo amorphous silicon AMOLED technology IGNIS Innovation demonstrated the latest achievements of its AdMo (Advanced Mobile) backplane technology for amorphous silicon thin film transistors IGNIS showed a high resolution 2.2-inch at 320x240 pixels (181ppi) demo with lifetime and uniformity performance that is better than its commercial polysilicon counterpart. In extensive in-house lifetime testing, IGNIS has demonstrated device lifetimes of over 50,000 hours, making them suitable for any mobile or handheld application, such as smart phones and A/V players. In addition, the AdMo technology is amenable to very high resolutions (250-300ppi) and medium size displays (10-15 inches). The sophisticated compensation technology is built entirely in-pixel, meaning low-cost driver ICs are used, lending itself to a simple “drop-in” display that is easily swappable into devices with legacy LCDs. It is also expected that the use of amorphous silicon will lower the unit manufacturing costs of AMOLED to less than the conventional LCD, while ensuring an adequate and stable supply of backplanes to manufacturers, when previously this was not possible with polysilicon. http://www.ignis.ca

ETRI develops highly efficient OLED light source The Electronics and Telecommunications Research Institute (ETRI) in South Korea has developed a highly efficient OLED light source that can attain 70 lumens per watt, which is more than four times the efficiency of regular light bulbs. “The white-light based bulb, which took three years to make, is as technologically advanced as those made in Europe, Japan and the United States, and effectively reduces the technological gap that existed in this field,” a researcher said. He claimed that with the latest development, South Korea has in effect nullified the five-year gap and will be able to compete evenly with other countries in the development of a commercial light source based on OLED technology. http://www.etri.re.kr/eng

The flexible OLED panel can display video at a

frame frequency of

60Hz


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Universal Display’s shows off flexible OLED bracelet Universal Display Corporation announced that its designer OLED bracelet. The bracelet uses the company’s energy-efficient phosphorescent, flexible, and transparent OLED technologies. The bracelet features a wrap around electronic OLED display using Universal Display’s phosphorescent OLED materials on a flexible metallic substrate. The resulting display is then integrated into a contemporary bracelet design. Emory Krall, Universal Display’s OLED prototype designer, transformed the company’s OLED bracelet concept into this wearable art form. This wearable concept utilizes the unique design capabilities of OLED technology, including its light and thin form factor and flexibility, as well as the low power consumption of the company’s PHOLED technology. Krall, who has designed a wide range of products including lighting and furniture, has had his work featured in numerous gallery exhibits, as well as various books and magazines. http://www.universaldisplay.com

White record OLEDs from Dresden University and Novaled surpass efficiency of fluorescent tubes The Technical University of Dresden and Novaled AG have reached 90lm/W at a brightness of 1,000cd/m2 for a real OLED lighting device and even 124lm/W when using a 3D light extraction system. In terms of power efficiency, fluorescent tubes are a benchmark for emerging technologies with some 50-70lm/W (considering losses in reflectors). “In our approach, we combine a novel, very energy efficient emission layer design with improved light out-coupling concepts, leading to this breakthrough” says project leader Sebastian Reineke, physicist at Institute of Applied Photophysics (IAPP, TU Dresden). “The power efficiencies of the record devices reach 90lm/W even if only flat, scalable out-coupling techniques are used. With special 3D out-coupling measures, even 124lm/W have been achieved.” Both values were determined in an integrating sphere with blocked substrate edges, only taking the light into account that is emitted to the forward hemisphere, CIE color coordinates are (0.41/0.49). An in depth article was published in Nature. http://www.novaled.com

Bayer MaterialScience and Add-Vision sign license agreement on polymeric OLEDs

Bayer MaterialScience (BMS) has signed a technology and patent license agreement with Add-Vision. The agreement grants BMS and its affiliates certain rights to manufacture and sell flexible polymer OLED displays using Add-Vision’s technology and intellectual property portfolio. Financial details have not been disclosed. http://www.add-vision.com

FDC and Universal Display Corporation make breakthrough in flexible manufacturing process The Flexible Display Center (FDC) at Arizona State University and Universal Display Corporation introduced the first a-Si:H active matrix flexible OLED display to be manufactured directly on DuPont Teijin’s polyethylene naphthalate (PEN) substrate. Implementing Universal Display Corporation’s phosphorescent OLED (PHOLED) technology and materials and the FDC’s proprietary bond-debond manufacturing technology, the 4.1-inch monochrome 320x240 display represents a significant milestone toward achieving a manufacturable solution for flexible OLEDs. The flexible backplane display was manufactured at the Flexible Display Center utilizing a 180°C thin film transistor process. The FDC’s facility implements traditional flat panel and semiconductor tools and processes to achieve flexible displays, enabled by its proprietary bond-debond technology to secure the plastic substrate to a rigid carrier during manufacture. The integration of Universal Display’s PHOLED frontplane delivers a key enabling technology for the flexible OLED. The PHOLED materials allow the OLED to convert up to 100% of the electrical energy into light, as opposed to traditional fluorescent OLEDs, which convert only 25%. Universal Display integrated the FDC backplane designed for its PHOLED frontplane to produce the display. http://www.flexdisplay.asu.edu http://www.universaldisplay.com


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NIST develops flexible memory components from polymer sheets The National Institute of Standards and Technology (NIST) has found a way to build a flexible memory component more cheaply from readily available materials and NIST has filed for a patent on the device. The device has potential applications in medicine, for instance, and appears to possess the characteristics of a memristor, a fundamentally new component for electronic circuits developed in 2008. Small medical sensors that can be worn on the skin to monitor vital signs such as heart rate or blood sugar could benefit patients with conditions that require constant maintenance. Though some flexible components exist, creating flexible memory has been a technical barrier, according to NIST researchers. The researchers took polymer sheets – like the transparencies for overhead projectors – and experimented with depositing a thin film of titanium dioxide on their surfaces by a sol gel process. By adding electrical contacts, the team created a flexible memory switch that operates on less than 10 volts, maintains its memory when power is lost, and still functions after being flexed more than 4000 times. The switch’s performance is similar to that of a “memristor”, a resistor that changes its resistance depending on the amount of current that is sent through it, and retains this resistance even after the power is turned off. The work is reported in the July 2009 issue of IEEE Electron Device Letters. http://www.nist.gov

A flexible electronic memory chip created from the same polymer sheets used to make overhead projector transparencies is shown on the left; on the right, the “memristor” can be flexed more than 4000 times

Purdue University develops invisibility cloak Using a specially tapered optical waveguide instead of exotic materials that require complex fabrication, researchers at Purdue University have created a simplified invisibility cloak that, unlike previous ones, works for all colors of the visible spectrum. The work makes possible the cloaking of objects larger than before and could lead to practical applications in the new field of transformation optics. The Purdue University research team used a tapered waveguide to cloak an area 100 times larger than the wavelengths of light shone by laser into the device. Previous experiments with meta-materials have been limited to cloaking regions only a few times larger than the wavelengths of visible light. The waveguide is inherently broadband, meaning it could be used to cloak the full range of the visible light spectrum. Unlike meta-materials, which contain many light-absorbing metal components, only a small portion of the new design contains metal. The device is formed by two gold-coated surfaces, one a curved lens, and the other a flat sheet. The researchers cloaked an object about 50µm in diameter in the center of the waveguide. Theoretical work for the design was led by Purdue, with BAE Systems leading the work on fabrication of the device. http://www.purdue.edu The design of a new type of invisibility cloak


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University of California Riverside discovers color-changing magneto-chromatic beads Microscopic polymer beads that change color instantly and reversibly when external magnetic fields acting upon the microspheres change orientation have been discovered by a research team at the University of California, Riverside. The beads or “magneto-chromatic microspheres” have excellent structural stability. They also are highly compatible with various types of dispersion media such as water, alcohol, hexane and even polymer solutions, allowing them to retain magnetically tunable colors in a variety of chemical environments. Applications of the new material include display type units such as rewritable or reusable signage, posters, papers and labels, and other magnetically activated security features. The new material can also be used to make environmentally friendly pigments for paints and cosmetics, as well as ink materials for color printing. Study results appeared June 15 in the online issue of the Journal of the American Chemical Society. “The new technology has a great potential for a wide range of photonic applications because the on/off switching of the diffraction color by the rotating photonic sphere is fast, greatly simplifying the pixel structures,” said Seoul National University’s Sunghoon Kwon whose lab collaborated with Yadong Yin’s Riverside lab on the research. “Therefore, the new technology is suitable for very large-scale displays, such as active signage.” In their lab experiments, the researchers embedded arrays of spatially ordered magnetic iron oxide nanostructures within each polymer microsphere, enabling its colors to be switched on and off simply by changing the microsphere’s orientation – or more precisely the orientation of the array. Furthermore, the new system has the advantage of producing bistable color states, required for making rewritable displays. http://www.ucr.edu

University of Tokyo makes cheap stretchable displays with elastic CNT-based conductor Using the same rubbery CNT-based conductor they developed a few months ago, researchers at the University of Tokyo have made a stretchable display. With the advantage of being printable, the development could lead to cheap, flexible and conformal displays. The earlier invented flexible CNT-based conductor has been used to connect OLEDs with the organic transistors addressing each OLED pixel. With improved conductivity and stretchability, it is now possible to fold the display in half or even crumple it up without damage, and to stretch it up to 50% of the original shape. A few months earlier, the flexible conductive material was used to connect organic transistors in a stretchable electronic circuit. At this stage, it was already clear that potential other applications for this flexible conductive CNT-based material are flexible displays, actuators and electronic skin for robots, etc. The process also increases the viscosity of the rubber material and thereby allows deposition by high-definition screen-printing. For the wire grid used to connect the transistors and the OLEDs of the flexible display, they printed 100-micrometer-wide lines using a printing mask. In comparison with other flexible electronics the rubber-like material offers the additional advantage that complex three-dimensional objects can be covered, which opens up new possibilities for applications. http://www.u-tokyo.ac.jp

Rotation of microspheres in a vertically changing external magnetic field. The color is switched between on

(blue) and off states

Stretchable mesh of transistors connected by elastic conductors that were made at the

University of Tokyo


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MIT develops screen based on cuttlefish Cuttlefish have inspired researchers from the Massachusetts Institute of Technology (MIT) to develop a screen that uses less than one-hundredth the power of an LCD TV. The mollusk’s ability to change its skin color extremely quickly prompted MIT to create a prototype screen that displays images by reflected light, rather than creating it. As a result, the screen only uses a few volts of electricity. The display only measures several square inches but it’s just one micron thick. It consists of up to 30 alternating layers of polystyrene and poly-2 vinyl - a conductive material that expands between the polystyrene layers when a voltage is applied to it. Changing its thickness changes the wavelengths of the light it reflects. Non-visible wavelengths, such as ultraviolet, can also be reflected, given the right thickness of material. http://web.mit.edu/

MIT develops peeling stickers leading the way to stretchable electronics A study of stickers peeling from windows could lead to a new way to precisely control the fabrication of stretchable electronics, according to a team of MIT-led researchers. Stretchable electronics, which would enable electronic devices embedded into clothing, surgical gloves, electronic paper or other flexible materials, have proven difficult to engineer because the electrical wiring tends to be damaged as the material twists. A study published in the online edition of the Proceedings of the National Academy of Sciences, June 15, offers a new approach to designing such circuits. MIT collaborated with the French National Center for Scientific Research. The research team did not have stretchable electronics in mind when they started, but launched the project as an analysis of the wrinkling and delamination of stickers. The small blisters that appear in stickers attached to car windows are a common example of such delamination. Alternatively, compression of the surface can also lead to delamination. As the surface is compressed, the film bends with it until it reaches a certain energy threshold, then pops away from the surface, forming small blisters. The researchers performed controlled experiments to stretch and compress surfaces with thin films attached to them, and measured the dimensions of resulting blisters. From their experimental data, the team developed a theory to explain the formation, size and evolution of the blisters. They found that blister size depends on the elasticity of the film and the substrate and the strength of adhesion between them. The researchers realized that by intentionally creating delaminated surfaces, they could design devices that allow wires attached to a surface to move with the material without breaking. If the wires are already partially separated from the material, they won’t break under stress from twisting and stretching of the substrate. The new study suggests that ultra-thin, flexible but strong materials such as graphene are ideal candidates for stretchable electronic applications. http://www.mit.edu

Two cuttlefish demonstrate a rare ability to change skin color in response to environment. Using the species as a model, MIT

scientists have developed an inexpensive but hi-tech screen that could be used in a variety of applications.

MIT mathematician Pedro Reis demonstrates the delamination that occurs when a surface is

compressed. The tape detaches from the surface and forms blisters of uniform size and spacing.


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Southampton University receives £6 million funding for meta-materials The UK government’s Engineering and Physical Sciences Research Council (EPSRC) has announced a new six-year program on nanostructured photonic meta-materials, to be established at the University of Southampton. EPSRC is covering costs for the new program with a grant of more than £6 million. Meta-materials are artificial electromagnetic media with unusual and useful functionalities achieved by structuring on a sub-wavelength scale. They employ the finest printing such as flexography and dip pen nanolithography because the feature size is less than the wavelength of light. They have this in common with the nano-antennas that are alternatives to photovoltaics being developed by Idaho National Laboratory. The aim of the project is to develop a new generation of switchable and active nanostructured photonic media thus providing groundbreaking solutions for telecoms, energy, light generation, imaging, lithography, data storage, sensing, and security and defense applications. All of the resources and interdisciplinary expertise available at the University of Southampton with partners in the UK and around the world will create a Nanostructured Photonic Meta-materials Research Center. The researchers hope to develop photonic media allowing for ultra-high-density integration, the lowest possible energy levels and the highest speeds of optical switching. This will be achieved by advancing the physics of the control, guiding and amplification of light in nanostructures and by developing new nanofabrication techniques and methods of hybridization and integration into the waveguide and fiber environment of different novel meta-material structures. The project, which is due to begin this July, will end in 2015. http://www.metamaterials.org.uk/

Creative Materials develops conductive ink for medical electrodes Two Creative Materials’ products, 113-09 electrically conductive ink, and 117-23 medical grade electrically conductive ink, have been developed for a range of medical electrode applications, including ECG and TENS electrode applications, transdermal drug delivery, defibrillation, and monitoring systems. These products feature excellent adhesion to a wide variety of surfaces, including polyester, polyimide, and glass. With a high percentage silver filler, 117-23 can be used in defibrillator electrodes, while 113-09 is used to make disposable ECG electrodes. http://www.creativematerials.com

University of Rochester develops photoluminescent nano-crystals with the potential for new lighting Scientists at the University of Rochester together with researchers at Eastman Kodak have created new “non-blinking” nano-crystals that constantly emit light. This development has the potential to be a cheap alternative for lighting applications or even an OLED successor. Nano-crystals, just a billionth of a meter in size, can absorb or radiate photons, by which they usually undergo what is called “blinking”. This change between the light emitting state and a “dark” period occurs because the energy of an absorbed photon is randomly transformed into heat instead of radiating away. The core/shell CdZnSe/ZnSe semiconductor nano-crystals created at the University of Rochester differ from that. They have a continuous gradient from the core to the shell, which eliminates the blinking and results in a steady stream of emitted photons. This could revolutionize lasers and lighting. With blink-free nano-crystals, lighting applications could be fabricated in an easier and cheaper process, which would apply only one fabrication step to create low-threshold lasers. To alter the color of the laser only the size of the nano-crystal needs to be changed. It could also become OLED’s successor. The idea is to simply paint a grid of nano-crystals emitting different colors onto a flat surface, and create paper-thin displays or even light emitting walls. http://www.rochester.edu


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Fraunhofer shows steering-wheel with an integrated OLED signage device The Fraunhofer Institute for Photonic Microsystems (IPMS) presented two recent project results realized inside the German OLED research association CARO. The acronym “CARO” stands for “Car OLED”, which focuses on highly efficient OLED devices for customer specific automotive applications (displays as well as signage devices). A recent design study was a steering-wheel with an integrated OLED signage device. Optrex Europe GmbH and Fraunhofer IPMS, together with the styling-studio G. Pollmann, developed a study based on a commercial steering-wheel with a car manufacturer. In the center of this steering-wheel is a white-emitting circular OLED signage device. In today’s vehicles LCDs are widely used in the instrument cluster, the central infotainment, and the climate control unit. The study of the CARO partners represents a potential new area of application for displays. In nearly every vehicle the emblem of the corresponding car manufacturer is integrated in the central position of the steering-wheel. Here an OLED display opens up a variety of new ideas and concepts for interior designers. Due to the thin construction depth of OLED displays, the integration of other components into the steering-wheel will not be influenced, in particular for the airbag. By opening the car doors the OLED could be activated and light up the emblem of the car manufacturer. If the ignition is switched on the emblem will be dimmed or completely switched off. Furthermore the display could be used to show warning instructions. Optrex Europe was responsible for the layout of the display, the manufacturing and the subsequent contour cut of the textured OLED substrate, as well as for the interconnection of the display including the implementation of different animations (each of the shown segments could be separately addressed). The processing of the OLED device itself was performed at the Fraunhofer IPMS in one of the existing OLED manufacturing lines. The styling-studio G. Pollmann GmbH created the concept of the study, built up the demonstrator and carried out the integration of the OLED display using multi-line addressing (MLA) for passive-matrix OLED displays. http://www.optrex.de http://www.ipms.fraunhofer.de

Sungkyunkwan University and the University of Nevada develop flexible tactile displays Researchers from Sungkyunkwan University in Korea and the University of Nevada in the US have developed a flexible tactile display that can wrap around the finger like a band-aid. The device could be used as a Braille display, among other applications. The researchers hope that the soft display might provide a means of communication for the visually impaired (for example, as a Braille display). It could also have applications as a tactile display cloth, virtual reality keyboard, tele-surgical glove, tele-feeling transferring system, and more.

160x80 pixel PMOLED display based on an orange emitting Novaled PIN OLED and driven by the

newly developed OLED MLA driver

CARO conducted a design study to create a steering-wheel with an integrated OLED

signage device.


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Polymer Vision and University of Cincinnati spearhead international research on electro-fluidic technology An international collaboration including the University of Cincinnati, Sun Chemical, Polymer Vision, and γ-Dynamics announced the development of electro-fluidic display technology (EFD). The partners say that EFDs will be the first technology to electrically switch the appearance of pigments in a manner that provides visual brilliance equal to conventional printed media. This new entry into the race for full-color electronic paper can potentially provide >85% white state reflectance, a performance level required for mass-consumer acceptance of reflective display applications such as e-books, cell phones, and signage. This work, which has been underway for several years, was published in the May 1 issue of Nature Photonics. Electro-fluidic displays use a Young–Laplace transposition of brilliant pigment dispersions.

The lead author, University of Cincinnati professor Jason Heikenfeld explains: “The ultimate reflective display would simply place the best colorants used by the printing industry directly beneath the front viewing substrate of a display. In our EFD pixels we are able to hide or reveal colored pigment in a manner that is optically superior to the techniques used in electrowetting, electrophoretic, and electrochromic displays.” As all forms of media content go mobile, Edzer Huitema, CTO of project partner Polymer Vision, sees tremendous growth opportunity for rollable displays offering large display/small form factor mobile devices. “Electro-fluidic displays combine the brilliant colors and video capability needed for the mass market. Coupled with the thin device structure required for rollable displays, this technology fits perfectly with Polymer Vision’s long term objectives.” The product offerings could be extremely diverse, including electronic windows and tunable color casings on portable electronics. To expedite commercialization, a new company has been launched: γ–Dynamics. Founding members of the company include John Rudolph (formerly Corning Inc.) and Jason Heikenfeld. γ–Dynamics is currently focusing on manufacturing process

Image of pigment droplets, and an overlay of three CMY prototypes

Images of electro-fluidic displays and pixels. a) Bright-field image of a 170dpi direct-drive demonstrator with ~30,000 pixels (left) and

pixel dark-field images (right). b) Time-lapse images of 500mm-square pixels. c) Hexagonal pixel with two separate ducts, one for the reservoir and one for the pixel border. d) Hexagonal pixels in

which the reservoir comprises only ~5% of the viewable area.


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development with a target of <$10/ft2 cost, and with focus on simple customization for numerous early product offerings. The technology team has a strong background in electrowetting displays, and is positioning the technology in a manner that circumvents many of the challenges currently facing electrowetting displays (reliability, bistability).

Heikenfeld told Flexible Substrate: “Unlike electrowetting displays, we can be bistable. That can reduce lifetime aging requirements by >1000, a huge advantage considering some of the challenges electrowetting displays currently face. At this time, we are not releasing technical details on the bistable aspect of the design, however.”

Conventional electrowetting displays reconfigure the contact angle of a colored oil film on a planar hydrophobic surface. In electro-fluidic displays, a three-dimensional micro-fluidic display device provides a direct view of brilliantly colored pigment dispersions. Electromechanical pressure is used to pull the aqueous dispersion from a reservoir of small viewable area (<10%) into a surface channel of large viewable area (>90%). The hydrophobic channel and reservoir respectively impart a small or large radius of curvature on the dispersion. Therefore, with no voltage, Young–Laplace pressure forces the dispersion to retract into the reservoir. Preliminary prototypes exhibit ~55% white reflectance, and future development points towards a reflectance of ~85%. Uniquely, compared to electrowetting pixels, the electro-fluidic pixels reduce the visible area of the colored fluid by an additional two to three times (improving contrast), are potentially bistable, are as thin as 15mm (giving potential for rollable displays), and can be miniaturized without increased operating voltage.

The team is welcoming inquiries regarding additional product development and strategic partnerships on volume manufacturing. http://www.ece.uc.edu/devices http://www.gammadynamics.net

Siemens develops a cheap, plastic X-ray imager Researchers at Siemens have discovered a way to print polymer X-ray-sensing panels that work just as well as expensive silicon ones. Using a new printing method, which is similar to the way that cheap plastic solar cells are made, the researchers believe that the approach could bring down the cost of medical imaging systems and be used to make lightweight, flexible imaging panels for procedures such as more comfortable mammograms. Electrically active polymers hold potential as a cheap alternative to silicon for devices including light sensors, solar cells, and transistors. Polymers can be processed in less stringent conditions – at room temperature and in the open air. While polymer-based photodiodes have been shown to work well for solar cells, the value of using polymer materials for imaging hasn’t been clear. The photodiodes developed by Siemens researchers work as well as those made of silicon. The researchers describe the manufacturing technique used to make them in the March issue of the journal Nano Letters. The detectors are stable for at least six years. The Siemens researchers make their photodiodes by spraying water-based solutions containing two kinds of polymers through a metal mask onto a glass substrate. They put down, first, several layers of a polymer with low conductivity, then several layers of a polymer with high conductivity. Lightweight, large-area, flexible X-ray imagers “would be a really nice gadget,” says Richard Lanza, a senior research scientist in nuclear science and engineering at MIT, who develops high-resolution X-ray systems. In the case of mammograms, breasts must be compressed to conform to the flat, rigid imaging panels. Conformable organic photodiodes might make such procedures far more comfortable. http://w1.siemens.com

The eight pink squares in the top image are polymer photodetectors. They were spray-printed onto the glass substrate. The image of a butterfly was recorded using a 256x256 pixel organic photo-

detector


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TopLED shows flexible LED curtains Shenzhen-based TopLED recently showed off a series of LED curtains that enable full-motion video across large outdoor surfaces in a flexible form factor. The company offers a variety of configurations, including curtains that measure up to 100 square meters. TopLED promotes advertising, event, and lighting solutions as the primary applications for the colorful curtain-based technology. http://www.topledscreen.com

UCLA and Stanford develop flexible carbon-nanotube super-capacitors It’s now possible to print out components for flexible circuits, resilient displays, and even lightweight X-ray imaging panels. But conventional energy-storage devices still weigh down these printed electronics. Now researchers at UCLA and Stanford University have made the first printable super-capacitor. This high-performance energy-storage device performs better than conventional super-capacitors currently on the market. The device, which is made up of a gel electrolyte sandwiched between two carbon-nanotube electrodes, could be created using existing ink-jet printing methods. While batteries store energy in chemical reactions, capacitors store it in surface charge, so they can provide rapid bursts of power. In digital cameras, for example, capacitors often provide a rapid pulse of power when the shutter button is depressed. Electrochemists are working on boosting the storage capacity of capacitors so that they can compete better with batteries, as well as on making batteries charge and discharge as fast as capacitors. But the researchers decided to focus on developing a simpler manufacturing method. The new capacitors are made by spraying carbon nanotubes onto two pieces of plastic, then sandwiching a gel electrolyte in between them. In the resulting device, one nanotube network acts as the positive electrode while the other functions as the negative electrode. When a voltage is applied to the electrolyte gel, charges collect on the surfaces of the nanotubes, storing energy. http://www.ucla.edu

Seiko Epson announces OLED TV breakthrough Seiko Epson Corporation announced a breakthrough technology that uses inkjet technology to uniformly deposit organic material for the production of OLED TVs in large screen sizes. The company says that the breakthrough is

a major step in developing 37-inch and larger OLED TVs with full HD resolution. Current OLED construction methods using vacuum thermal evaporation technology has a technical limitation that prevents it from being used to create large screen OLED TVs. The Epson breakthrough uses a proprietary “Micro Piezo” inkjet technology to achieve a much greater accuracy in organic material deposition than current technology. The layers produced using the technology are very uniform with less than 1% volume error. The new construction method was presented at SID 2009. The company also showed a 14-inch prototype OLED TV with HD resolution built using the process (see photo). http://www.epson.co.jp/e/

This super-capacitor was printed by spraying mats of carbon

nanotubes onto two pieces of plastic, then sandwiching a

polymer gel in between

Credit: Nano Letters/ACS


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MIT creates a camera from a sheet of fiber Researchers at MIT are finding ways to turn silk into sensors by adding biological molecules to it, and turn cotton sheets into electronic fabric by bathing them in a solution of nanotubes. The idea is to use the electronic textiles, which are flexible and can be worn comfortably, to sense such things as the blood of a soldier or pathogens circulating in the air. They have integrated a collection of light sensors into polymer fibers, creating a new type of camera. A camera made from fibers could be lightweight, robust, and even foldable. Such a fiber-based camera could be used in a large foldable telescope or integrated into soldiers’ uniforms. In the researchers' most recent work, they integrate eight sensors into a polymer fiber – more than ever before. In order to make the camera, the researchers integrated the eight semiconducting light sensors into a polymer cylinder with a diameter of 25 millimeters, controlling the sensor's spacing and angle within the fiber. Once the sensors, made of a type of semiconducting glass, were in position, the polymer cylinder was heated and then stretched so that the diameter shrank the diameter of hundreds of micrometers – a process that is identical to the way in which commercial fiber is made for telecommunication applications – retaining the orientation of the sensors. http://www.mit.edu

DuPont Displays surpasses million-hour milestone for lifetime of new OLED material DuPont Displays announced it has developed a new, proprietary third generation (Gen 3) solution-based OLED materials technology, which has led to substantial performance gains for printable OLED light-emitting materials. A DuPont Gen 3 green OLED material achieved a record lifetime of over 1,000,000 hours, while two new Gen 3 solution blue materials have been developed that set new standards for longevity and color, the company says. Gen 3 OLED materials can meet or exceed the performance of today’s vapor deposited materials, and are paving the way for lower cost solution process OLED displays. The new Gen 3 green material developed by DuPont represents a major lifetime milestone of one million hours, which equates to over 100 years of constant usage. This green material demonstrates a current efficiency of 25cd/A and excellent color coordinates (0.26, 0.65). Although green material lifetimes already exceed those of red and blue, the significance is that in a display, green contributes more to the white brightness. The longer lifetime also can lead to an increase in total display lifetime. Historically, performance of blue light-emitting materials has been the most challenging. However, DuPont Gen 3 solution blue materials are demonstrating world-class performance. One of the Gen 3 blue materials has color coordinates of (0.14, 0.12), a current efficiency of 6.0cd/A, and a lifetime of 38,000 hours from 1000cd/m2, which is one of the longest blue OLED material lifetimes publicly reported. A second material has been developed with exceptionally deep blue color coordinates of (0.14, 0.08), a current efficiency of 3.9cd/A, and a lifetime of nearly 7,000 hours. Due to its deep blue color, the lifetime of this material at the luminance required for a 200cd/m2 display is calculated to be approximately 41,000 hours. In addition, a high-performing red solution OLED material developed by DuPont has a lifetime of 62,000 hours, current efficiency of 13cd/A, and color coordinates (0.68, 0.32). http://www.DuPont.com

The camera is made of a collection of polymer fibers, each of which

consist of eight semiconductor light

sensors that circle the center of the fiber, as

shown in this scanning electron microscope

image Credit: Yoel Fink, Fabien

Sorin


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Ennova Direct awarded retractable biometric USB flash drive patent with OLED display Ennova Direct announced its new patented biometric USB flash drive with interactive OLED display and retractable USB connector. With USB flash drive memory capacities now reaching 64GB and higher, user’s are

now utilizing their USB flash drives as full external backup drives, making it even more important for users to secure the large amounts of personal data they are storing on their USB flash drives Ennova Direct Corporation announced that the USPTO recently awarded the company another USB Flash Drive patent – US 7,462,044. This new USB flash drive has unique patented features including a new type of retractable USB connector with a built-in cover that protects the flash drive’s OLED screen. The OLED screen comprises an integrated biometric fingerprint scanner, which changes color to indicate the success or failure of a match of the user’s stored fingerprint. The OLED screen is also an interactive interface that allows the user to select specific files and initiate specific functions. Ennova Direct expects to launch their new patented retractable biometric USB flash drive under their ION Technologies brand in Q1’2010. http://www.ennovadirect.com

Philips perseveres with its Lumiblade concept Philips is expanding the profile of its Lumiblade lighting concept that uses OLED lightweight panels. When switched off, the panel resembles a mirror. But as soon as a current is applied, the panel lights up, casting out a gentle, evenly dispersed glow of light. Lumiblade gives no flickering of light, no glare and no excessive heat emission. An extensive color palette is available, and the panels are versatile, flexible in size and shape use. Philips has developed three Lumiblade concepts and has made them interactive, responding directly to gestures and movements. The Lumiblade Mirrorwall is the brainchild of London-based design company Random International, and takes a basic wall and covers it with small, reflective OLEDs to create an interactive mirror. When all the OLEDs are switched on, the wall casts out a gentle glow of light. But if someone stands in front of the wall, the OLEDs directly in front switch off, allowing the panels to form a mirror. Take a step to the right or left, and the mirror will move along making the most of the fast response time, the integration possibilities and the playful nature of the Lumiblade. Alternatively, Lumiblade E27, a creation from German designers Hosseini/Richter features an array of OLEDs that reveal the traditional shape of an E27 lightbulb from certain angles. It demonstrates the flexibility and visual impact of the new Lumiblade at the same time as offering a nod to the lighting heritage of Philips. http://www.lumiblade.com


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Bridgestone claims practical substitute for ITO Bridgestone Corp has come up with a material that could replace ITO used to manufacture transparent electrodes for the company’s e-paper. The company made this announcement in a symposium at SID Display Week 2009. This speech was marked as “withdrawn” in the program handed out to the participants, indicating that the speaker could not come from Japan to make the speech. However, the speech was delivered through the use of PowerPoint and an audio system. Bridgestone has already developed its own e-paper technology, but the fragility of ITO was a problem in realizing flexible e-paper. To solve the problem, the company focused on an organic material known as PEDOT/PSS. The conductivity of PEDOT/PSS was low at about 1S/cm in the early 1990s, when the material was first developed. But it was rapidly enhanced, and some of the materials now have a conductivity exceeding 1,000S/cm and are attracting much attention. The optical transmittance of PEDOT/PSS materials that are used for transparent electrodes is about 86% when the sheet resistance is 300 to 400Ω/sq. The company considers that the 86% transmittance is high enough for use in e-paper. A transparent electrode made by coating ITO on PET has an optical transmittance of 87.5% in the 550nm wavelength light when the sheet resistance is 200Ω/sq. The important point in using PEDOT/PSS for e-paper is the method of forming matrix electrode patterns. This time, Bridgestone employed the laser ablation method. Specifically, an excimer laser was scanned over a photo mask to form the electrode pattern. With this method, a productivity equivalent to that of ITO can be realized, according to the company. Also, Bridgestone compared an e-paper made using a PEDOT/PSS transparent electrode with one incorporating an ITO transparent electrode. As a result, the reflectance of the former e-paper was only 1% less than that of the latter e-paper when they display white color or black color. And there was not a big difference in contrast ratio durability between the two. http://www.bridgestone.com

NanoMarkets releases new report on conductive coatings in electronics markets A new report from NanoMarkets predicts that new opportunities are rapidly emerging in the conductive coatings market as the result of new applications and novel materials. Once a highly mature sector centered on coating or plating metals for equally slow-growing applications, the conductive coatings market will see a growth spurt brought on by demanding new requirements for electrodes, EMI/RFI shielding, and antistatic protection from next-generation electronics and energy devices. At the same time, new materials ranging from carbon nanotubes to conductive polymers to advanced composites will provide significant competition to traditional metal coatings on cost, environmental and performance grounds. NanoMarkets’ projections place the conductive coatings markets at $12.2 billion in 2014 going on to reach $15.9 billion in 2016 for the critical applications covered in electronics discussed in the report. Key findings are that electrode coatings with enhanced conductivity will prove a key enabling technology in emerging areas such as large area sensors, fuel cells and especially photovoltaics (PV). NanoMarkets believes that advanced materials – such as mixtures of silver and transparent conducting oxides – could provide a way forward to higher efficiencies in solar panels. Conductive coatings sold into the photovoltaics sector will reach $1.6 billion in revenues by 2014. http://www.nanomarkets.net

A comparison of PEDOT/PSS (red) and ITO (blue) used for flexible e-paper. The lower the cost, the higher the rating.


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DNP produces printed transparent conductive film to replace ITO Dai Nippon Printing Co Ltd (DNP) has developed a transparent conductive film that is designed to replace indium tin oxide (ITO) films. In place of expensive indium, DNP used silver for the conductive particles. Not only can the film be formed with patterns in desired areas by a printing method, which is suitable for mass-production, it is also flexible. It intends to replace ITO films used in touch panels, OLED panels and electronic paper. The company started shipping samples in May 2009 and will sell the film on a full-scale basis from fall 2009. This time, DNP improved the printing method and the materials so that the patterns can be uniformly formed only on the required area of the film substrate. This eliminates a number of production steps such as vapor deposition and etching, while enabling continuous roll-to-roll processing with the use of an approximately 1,000mm-wide film. On the other hand, to form a pattern in the desired area on an ITO film, a number of steps such as light exposure, development, etching and cleansing are required after a conductive material is deposited on a film. When a pattern is formed on a flexible film by a printing method, it is possible to prevent cracks and scratches, which may occur when the film is being bent, by forming conductive particles in a fine mesh pattern, DNP said. By carefully selecting process materials and improving working process, the company achieved a resistance of 0.1Ω/cm2 with the new film. Also, the newly developed film functions as a lightweight, thin and flexible transparent wave absorber. Because its mesh portion was designed with a pitch of several dozen microns to several millimeters, the film can block radio waves in a given frequency. For example, the film can be used to block mobile phone signals when it is attached to glass walls, windows, doors, etc., in hospitals. In contrast, when ferrite is used as a wave absorber, it needs to be embedded in a glass plate. http://www.dnp.co.jp

Asahi Kasei enhances polymer conductivity by 100 times Asahi Kasei Finechem has developed polyvinyl sulphonic acid (PVS) that is used as a dopant for conductive polymers. The company said it has developed a method to polymerize high purity PVS, which has been considered as difficult. The new PVS was used as a dopant for polyethylenedioxythiophene (PEDOT) to realize an electric conductivity as high as 126S/cm. The conductivity achieved by this method (PEDOT/PVS) is about 100 times higher than the value achieved by a method that uses polystyrene sulphonate (PSS) as a dopant (PEDOT/PSS), according to the company. In addition, materials produced by the PEDOT/PVS method improved the smoothness of base plates on which the materials were applied, compared with materials produced by the PEDOT/PSS method, when they were applied under the same conditions. Furthermore, the ultraviolet transmittance in the 200 to 300nm range significantly improved because the PEDOT/PVS method is not affected by the absorption caused by aromatic rings in styrene sulfonate acid. Asahi Kasei Finechem plans to apply conductive polymers produced by the PVS method on OLED devices and solar cells. AGFA-Gevaert NV of Belgium and its partners already prototyped a flexible OLED panel using the PEDOT/PSS material as a transparent electrode. http://www.asahikasei-fc.jp/eng

UCLA researchers develop new method for producing transparent conductors Researchers at UCLA have developed a new method for producing a hybrid graphene-carbon nanotube, or G-CNT, for potential use as a transparent conductor in solar cells and consumer electronic devices. These G-CNTs could provide a cheaper and much more flexible alternative to materials currently used in these and similar applications. The new processing method was published in Nano Letters. The G-CNT hybrid, the researchers say, provides an ideal high-performance alternative to ITO in electronics with moving parts. Graphene is an excellent electrical conductor, and carbon nanotubes are good candidates for transparent conductors because they provide conduction of electricity using very little material. The new single-step method for combining the two is easy, inexpensive, scalable and compatible with flexible applications. G-CNTs produced this way already provide comparable performance to current ITOs used in flexible applications. G-CNTs are also ideal candidates for use as electrodes in polymer solar cells. G-CNTs retain efficiency when flexed and also are compatible with plastics. Flexible solar cells could be used in a variety of materials, including the drapes of homes. http://www.ucla.edu


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Ambipolar organic semiconductor material claims high charge mobility says Tokyo University and JST A Japanese research group claimed that it developed a new ambipolar organic semiconductor material with the “highest level” charge mobility as an amorphous material. The material, “CZBDF”, was developed based on a derivative announced by the research group, which is led by Tokyo University and the Japan Science and Technology Agency (JST), in 2007. The derivative has a mother nucleus of benzodifuran, an annulated π-conjugated compound containing oxygen atoms. The benzodifuran derivative is an amorphous thin film p-type semiconductor material with a high hole mobility. This time, the research group replaced the amine portion in the benzodifuran derivative with carbazole and realized the CZBDF ambipolar material with high charge mobility. Also, the group produced a homojunction OLED device with the use of CZBDF and succeeded in achieving EL emission by using both fluorescence and phosphorescence, as well as EL emission of three primary colors of blue, green and red. The CZBDF amorphous thin film has a hole charge mobility of 3.7x10-3cm2/Vs and an electron charge mobility of 4.4x10-3cm2/Vs. http://www.u-tokyo.ac.jp

The voltage and external quantum efficiency characteristics (graph on the left) of homojunction OLED devices with the intermediate layer doped with a dye, and the emission of the device (lower right)

UDC and Samsung Mobile Display present advances in long lifetime green phosphorescent OLEDs Universal Display Corporation announced new highly-efficient green PHOLED performance advances. It has been used in a top-emission PHOLED device architecture. Using this approach, the team achieved two milestones. A green PHOLED with NTSC color at CIE(0.20, 0.73), high luminous efficiency of 110cd/A, and a low voltage of 3.6Vat 3,000cd/m2 was achieved. A second device structure using this green PHOLED material system also achieved an ultra-high luminous efficiency of 160cd/A along with CIE(0.28, 0.69) and low voltage of 3.8V at 3,000 cd/m2. These compare to a standard bottom-emission device with CIE(0.33, 0.62) and 52cd/A using this same green PHOLED material system. Replacing the green fluorescent OLED material typically used today in an AMOLED with this new green PHOLED can result in a significant 37% power saving. The operational lifetime for this green PHOLED material system is also very good. A bottom-emission device using this material system offers >300,000 hours to 50% (extrapolated) and 15,000 hours to 90% of the initial luminance of 1000cd/m2 (defined as LT90). With these top-emission devices, the LT90 lifetime is 28,000 hours and 6,400 hours, respectively, for the 110cd/A and 160cd/A devices. http://www.universaldisplay.com


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Stanford University creates transistors from carbon nanotube networks Stanford University researchers have created very thin, high-performance transistors using networks of carbon nanotubes deposited onto flexible surfaces. Single-walled carbon nanotubes (SWNTs), each resembling a tiny seamless cylinder of chicken wire, have many properties that make them attractive for electronics research. They conduct electricity well, are mechanically strong, and chemically stable, and research groups across the world are investigating how to use them to create new electronics, particularly bendable electronics applications such as flexible roll-up display screens and electronic “skin”. These applications require thin semiconducting films – thin transistors, essentially – uniformly deposited onto large, flexible substrates, such as polymers, using methods that are compatible with large-scale manufacturing. But such methods have so far eluded scientists, partially because large amounts of SWNTs tend to be too disorganized to be suitable for incorporation into devices. They are randomly aligned, have different chiralities (that is, have molecular structures that are not symmetric), and can bundle together. The group chemically modified a polymer surface with a very thin layer terminated with an amine, a compound belonging to class of organic compounds derived from ammonia. The researchers then deposited the nanotubes via spin-coating and a solution containing SWNTs is applied to it. The method yielded a layer of SWNTs that did not bundle and were well aligned. Further, the chemical properties of the amine layer allowed the nanotubes to self-sort their chiralities. http://www.stanford.edu

Drexel nanotechnology research opens way to smaller electronic devices Drexel University is close to making personal electronic devices even smaller. Their research, published in the April 26, 2009, online version of Nature Nanotechnology demonstrates that it is possible to manipulate a carbon nanotube for the future miniaturization of electronic devices, including computers, cell phones, and PDAs. The Drexel researchers demonstrated that it is possible to create periodic, alternating patterns on carbon nanotubes with a period of 12 nanometers by decorating carbon nanotubes with carefully selected crystalline block copolymers. They achieved an alternating pattern on an individual carbon nanotube at a ~10nm scale. By controlling the electrical conductivity of the areas occupied by each block, or domains, multiple transistors can be fabricated along the length of the nanotubes. The small domain size allows the possibility for hundreds of transistors to be fabricated on a 10-micrometer tube. http://www.drexel.edu

ASU’s Flexible Display Center and UT Dallas develop flexible CMOS circuits Arizona State University’s Flexible Display Center (FDC) and the University of Texas at Dallas (UT Dallas) announced that they have successfully produced CMOS circuitry on a flexible plastic substrate. Primarily designed to advance flexible electronics, the new plastic CMOS circuits have demonstrated exceptional power efficiency, one-third the power consumption of traditional thin film transistor circuitry, making flexible CMOS ideal for potential applications such as smart medical bandages or triage patches. The research and development project has focused on integrating two types of thin film transistors (TFTs), n-type amorphous silicon and p-type organic silicon, to fabricate CMOS logic gates on flexible polyethylene napthalate (PEN), a high-temperature polyester film. The electrical duality between the NMOS and PMOS transistors achieves dramatically reduced power consumption for flexible circuits. http://www.utdallas.edu

Polymertronics introduces OLED plasters to kill skin cancer Polymertronics, a start-up company in the UK, is introducing new light emitting plastics and electronic hardware for wearable photodynamic (PDT) applications for photodynamic therapy. The new glowing bandages, made of plasters embedded with OLEDs, will allow skin cancer patients to treat themselves at home, making treatment faster and more accessible. Polymertronics also introduced the Red Diamond OLED development kit, which enables production of OLED displays for prototyping. Each kit includes essential chemicals and electronics to rapidly manufacture devices on glass and flexible substrates. http://www.polymertronics.com


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NICT develops wearable electrocardiograph using body area network Japan’s National Institute of Information and Communications Technology (NICT) developed an electrocardiograph that can be worn like an accessory with the help of Yokohama City University and Research & Innovation for the Environmental Health Medicine (RIE). The electrocardiograph uses BAN (body area network), a short-distance wireless communication technology used for communications between devices close to the human body and a sensor in the body. It can continuously perform an electrocardiogram for 24 hours and wirelessly transmit the measurements just by being worn around the neck like a necklace. NICT expects the electrocardiograph to be used for personal health management in everyday life and remote monitoring of patients, etc. The new electrocardiograph not only can perform an electrocardiogram but also can measure changes in body surface temperature and body posture. Because of its light weight of about 20g and dry measurement electrodes that do not require gel, wearing it around the neck is not uncomfortable, NICT said. BAN is currently being standardized at IEEE802.15.6. http://www.nict.go.jp

Georgie Davies wins competition with cell phone dress Georgie Davies, a student at the London College of Fashion, won a Sony Ericsson sponsored competition to explore the relationship between technology and fashion. Georgie Davies created a call indicating dress as she wanted to find a way to alert a person when their mobile phone rings in a noisy environment like a bar or club. Her design is a cocktail dress made up of interactive scales, inspired by butterfly wings. When the phone rings, the dress subtly lights up.

The newly developed electrocardiograph (right) and the measured data being displayed on a mobile phone using BAN (left)


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Hong Kong Polytechnic University develops platform for e-textiles and wearable computing Researchers at the Hong Kong Polytechnic University presented the TeeBoard, a constructive platform for e-textiles and wearable computing, at the recent CHI 2009 conference in Boston in April. It is designed specifically to “lower the floor” for the integration of e-textiles into educational computing. Recent developments in this field raise the possibility of e-textile construction kits for hobbyists and novices alike. The unique nature of wearable computing and e-textiles also gives it a lot of potential as an educational computing topic, as it allows students to exercise their creativity and imagination while learning about computing and technology. Current state of the art technology and techniques are not yet robust or reliable enough to stand up to the demands of educational computing, and they require a high level of skill from the user. The researchers evaluated the TeeBoard on both technical and pedagogical aspects, by measurement and experimentation, including real-life use in the environment of a summer workshop. The TeeBoard survived the workshop and the wearability wash-tests without any problems. In the environment of the workshop, the TeeBoard also greatly facilitated the creativity and learning process of the student participants. On an educational pedagogy front, they believe that the TeeBoard is also a big step towards a wider-scale use of wearable computing in education. A small pocket was constructed in an unobtrusive location on the inside of the TeeBoard, which was big enough to hold a small rechargeable lithium battery, or a battery holder for AA-size alkaline batteries. For the power supply, they soldered wires, snap buttons and a switch directly to the terminals of a rechargeable 7.2V lithium battery, which was then “plugged in” by snapping the buttons directly to the appropriate bus strips. The right-hand picture shows the inside of a TeeBoard circuit: the pocket containing the power supply battery can be seen on the bottom right of the garment. http://www.polyu.edu.hk/

The front side of the finished TeeBoard, with a demonstration circuit demonstrating the ability to accommodate circuits on both sides of the garment. The inside of the TeeBoard (right) has attached the electronic components, including the microcontroller board in the center “socket”, and a number of connecting wires. The outside of the TeeBoard has attached a light sensor on the right shoulder (circled) and six LEDs (wrapped in colored gauze to

simulate flower decorations).

Fraunhofer and TU Berlin work on interactive dress Klight is an interactive dress which translates the body’s movement into light, connecting the body with its surroundings. To achieve the effect, a new stretchable circuit board technology, developed by Fraunhofer IZM, was integrated into the dress. The dress features integrated diodes, an accelerometer and a microcontroller, which detect the wearer’s movements and convert the dynamics into an LED-display pattern. The integrated LED display is made possible by the stretchable substrate. The manufacturing process for these stretchable circuit boards (SCB) was developed by scientists at Fraunhofer IZM and TU Berlin as part of the European research project STELLA (STretchable ELectronics for Large Area Applications). To achieve the required flexibility needed while integrating electronics into textiles the highly conductive but basically rigid copper wires are structured into the substrate in tiny meander patterns. Depending on the design of the meander shapes, the Fraunhofer researchers are able to achieve elasticities of up to 300%. http://www.izm.fraunhofer.de


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Carnegie Mellon University conducts research into best place to locate wearable displays

Researchers at Carnegie Mellon University, Pennsylvania, described at CHI 2009 a study that evaluated reaction time performance to visual stimuli at seven different body locations. Results indicate numerous and significant differences in the reaction time performance characteristics of these locations. Previous research has investigated where computers can be located on the human body – critical for successful development and acceptance. However, for a location to be truly useful, it needs to not only be accessible for interaction, socially acceptable, comfortable and sufficiently stable for electronics, but also effective at conveying information. They selected seven locations per participant. Their investigations looked at issues such as device weight and size. Although electronics have miniaturized considerably over the past decade, ameliorating these factors, many classes of devices are bounded by the size of their screens and input controls, which cannot be readily reduced (e.g., mobile phones as we know them today will never fit on one’s finger). However, devices that do not require traditional screens or input controls can be very small, especially if supported computationally via a PAN. They showed that there are significant differences in how visual alerts distributed on the human body capture our attention. This reaction time performance is not only influenced by the innate properties of each location, such as physical distance or visual accessibility, but also outside factors, such as occlusion by furniture. They believe these data and observations can inform the design of future on-body visual displays. http://www.cmu.edu/

Above: one of seven sensors worn by participants to determine reaction time to visual stimuli. Right: the seven body locations selected for evaluation.

Samsung shows off intriguing concept designs that incorporate flexible displays At Samsung's recent "Sdium" showroom in Korea in early June, the company showed off radical-looking models of flexible displays. One concept shows a rollable solution that functions like a scroll. Another concept enables video viewing in a wrist-watch form factor. http://www.samsung.com


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Displaybank releases thin film solar cell technology and market forecast Displaybank just released its “Thin Film Solar Cell Global Market Forecast (2008 to 2013)”. A thin film solar cell is an active layer for electricity production that deposits thin film on substrates like glass instead of silicon wafer. It has strength in manufacturing large area solar cell module at an inexpensive price since it reduces the amount of semiconductor material needed in solar cell production. The types of thin film solar cell currently being researched for industrialization include a-Si:H, CdTe, and CuInSe2 based solar cells. They are being actively developed by about 150 companies in and out of Korea. The thin film solar cell market is categorized by field and device to

forecast that the market is expected to continuously record 72% average annual growth rate until 2012 and is likely to account for 29% of the total solar cell market by 2013. http://www.displaybank.com

Thin film solar cells: Global Solar (upper left) and Sharp (lower left); on the right is DisplayBank’s thin film

solar cell global market forecast (2007~2013)

Infinite Power Solutions launches its THINERGY micro-energy cell Infinite Power Solutions (IPS), a maker of solid-state, rechargeable, thin-film micro-energy storage devices, unveiled its THINERGY family of micro-energy cell (MEC) products and accompanying technical specifications. THINERGY MECs are the world’s most powerful batteries for their size and outperform all other micro-batteries (primary and rechargeable), including Li coin cells, printed batteries and other thin-film batteries (TFBs). Extremely small and powerful, these ultra-thin MECs are also reliable, safe and eco-friendly. IPS reports that its THINERGY MECs, when recharged over their lifetime, provide tens of Watt-hours of energy, equivalent to or more than traditional primary cells that are hundreds of times larger in total volume. Combined with ambient energy harvesting, THINERGY MECs deliver perpetual power to wireless sensor nodes and other micro-systems for more than a decade of maintenance-free operation. As a result, these products represent a new class of electronic component that bridges the performance gap between batteries and super-capacitors. In fact, the unprecedented discharge current demonstrated by THINERGY MECs makes it the first technology suitable for replacing super-capacitors in many applications. IPS announced four standard products within its THINERGY MEC family. Two products are available now, the THINERGY MEC101 and THINERGY MEC120, with capacity options up to 1.0mAh and 0.4mAh, respectively. The other two products (one larger and one smaller in both size and capacity) will be available later this year. http://www.InfinitePowerSolutions.com


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Infinite Power Solution achieves record-breaking performance in micro-energy cells Infinite Power Solutions, Inc. (IPS), a leader in the manufacturing of high performance solid-state, rechargeable, thin-film micro-energy storage devices, announced it achieved record-breaking current density and recharge cycles, beyond that of any lithium-based rechargeable battery currently on the market. The announcement marks a significant milestone together with the technology’s ultra-low self-discharge current and perpetual recharge capabilities via energy harvesting. In recent tests, IPS demonstrated a continuous discharge current measurement of 170mA at 25°C from a single MEC, 1 square-inch (25.4x25.4x0.17) in size. This translates to an active area continuous current density of 45mA/cm2. Considering a starting discharge capacity of 0.7mAh, this high current equates to a nominal 240 capacity rate (C-rate). In comparison, a typical Li-ion cell phone battery delivers less than 10mA/cm2, or four times less current per unit area. Although cell phone batteries are hundreds of times larger in total volume, they typically generate less than 2 C-rate. IPS also reports it has demonstrated industry-leading deep discharge cycle capability with its high capacity MECs. The company tested 0.7mAh, 1 square-inch rechargeable cells to 100% depth of discharge (DOD) at 25°C for greater than 15,000 cycles at 9 C-rate with approximately 90% of their starting capacity maintained, as verified at the capacity-defining ½ C-rate. Other rechargeable batteries, such as Li-ion, Li-polymer and NiMH cells are usually cycled to only 80% DOD and rarely achieve 1,000 cycles with 80% capacity retention. http://www.InfinitePowerSolutions.com

Umeå University develops cheap solar cells Physicists at Umeå University in Sweden have developed a new and simple method for producing cheap electronic components. Electronic components with various functions can be created by patterning a film with a specific structure. Until now it has proven to be problematic to carry out this patterning in a simple way without destroying the electronic properties of the organic material. A thin film of an organic electronic material, a fullerene, is first painted on a selected surface. The parts of the film that are to remain in place are directly exposed to laser light. Then the whole film can be developed by rinsing it with a solution. A well-defined pattern then emerges where the laser light hit the surface. A key advantage with this method of patterning is that it is both simple and scalable, which means that it can be useful in future production of cheap and flexible electronics in an assembly line process. The findings are presented in the publication Journal of the American Chemical Society (2009, 131, 4006-4011). http://www.umu.se

Konarka and Arch Aluminum & Glass sign advanced product development agreement Konarka Technologies announced the company has entered into an advanced product development agreement with Florida-based Arch Aluminum & Glass. The companies plan to collaborate on building integrated photovoltaics (BIPV), photovoltaic materials used to replace conventional building materials. The memorandum of understanding outlines the integration of Konarka’s patent-protected thin film solar material into glass for various commercial BIPV applications. BIPV is one of the fastest growing segments of the photovoltaic industry. Arch Aluminum specializes in a wide range of artistic and architectural glass products to keep pace with the demands of today's architects, designers and building developers. The company offers in-house laminating, heat-treating and fabrication technology as well as selective, engineered, off-the-shelf aluminum and glass products. In October 2008, Konarka opened the largest roll-to-roll flexible thin film solar manufacturing facility in the world, preparing for the commercialization and mass production of its solar material for various market segments including sensors, consumer products, tent and fabric structures, greenhouses, marine and boating, building construction, as well as fashion and accessories, among others. http://www.archaluminum.net http://www.konarka.com


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SRS Energy and US Tile team to create stylish solar tiles SRS Energy has partnered with US Tile to design solar panels with the exact same shapes as their clay counterparts. The result is solar tiles that can be seamlessly integrated with the terra-cotta tiles. The Philadelphia-based company hopes that solar will become part of the architecture and building of residences and commercial properties. BIPV (building-integrated photovoltaics) have been around for a while, but many of them fail to visually blend in with the existing architecture. SRS Energy is trying to improve that by partnering with roofing companies to replicate existing roof tile designs into thin-film solar panel counterparts. The Solé Power Tile system has been implemented in a Swiss chalet-like building is Zwahlen's Ice Cream & Chocolate Company, a family-run ice cream parlor in Audubon, Pennsylvania., owned by SRS Energy's CEO Marty Low.

US Tile's Solé Power Tile system will begin to be installed in homes this November 2009 by contractors that have taken the company's Solé certification class, the first of which will be held this July, The company plans to move into other U.S. and European markets in 2010.

The Solé Power Tile system, which is warranted for 20 years to generate electricity at a rate of 80 percent of capacity, incorporates triple-junction amorphous solar cells produced by Uni-Solar. Cell efficiency for the tiles is between 8 percent and 10 percent. SRS Energy's statistics say the average homeowner with Solé Power Tiles can get 860 kilowatt hours per square (or per 100 square feet) annually in an area with "5.8 peak sun hours" per day. http://www.srsenergy.com

UCSB develops a polymer solar cell with near-perfect internal efficiency A group of scientists led by University of California at Santa Barbara has developed a polymer-based solar cell with an ability not yet seen in similar cells: almost every single photon it absorbs is converted into a pair of electric-charge carriers, and every one of those pairs is collected at the cell’s electrodes. The overall efficiency of the cell is 6%, when illuminated in the lab with simulated solar light. The researchers tried an approach that would retain a typical active layer thickness, about 80 nanometers, yet maximize the photocurrent. They added another layer to the cell, a sheet of titanium-oxide sandwiched between the copolymer and the top electrode, which has two roles. First, it redirects the intensity of the light such that it is maximized in the active layer. With higher intensity light reaching the active layer, the photocurrent increases. Second, it acts as a “hole blocker”, helping to keep the photo-generated electrons from recombining with holes. The group discovered that at a copolymer-to-fullerene ratio of 1:4, the internal quantum efficiency is close to 100% for light with a wavelength of 450nm and above 90% for all other wavelengths in the absorbed spectrum. The work was published in Nature Photonics. http://www.ucsb.edu

Solé Power Tile system developed for US Tile by SRS Energy integrates seamlessly with its terra-cotta counterparts.

Zwahlen's Ice Cream & Chocolate Company sporting Solé Power Tiles.


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Southampton University use quantum dots to boost solar cell efficiencies Researchers at Southampton University have combined the light-absorption ability of quantum dots with the current-generating capacity of a bulk semiconductor to enhance solar cell efficiency, according to Physics World. They attached nano-crystal quantum dots to patterned semiconductor layers. The approach exploits the phenomenon of non-radiative energy transfer and could, say the researchers, lead to a new generation of more efficient solar cells (Physical Review Letters 102 077402). They etched an array of rectangular channels some 500nm wide into a layered semiconductor structure. The structure comprised a multiple-quantum-well (MQW) layer sandwiched between a p-type layer and an n-type layer. The MQW itself comprised 20 layers of gallium arsenide, each about 7.5nm thick. They then deposited a solution of cadmium-selenium quantum dots, each just a few nanometers across, onto the structure. They are now designing devices that can combine this feature of non-radiative energy transfer with carrier multiplication by appropriate engineering of the p–n junction and choice of materials for the quantum dots. Such devices will exceed the 31% efficiency limit. http://www.soton.ac.uk

QD Soleil announces allowance of claims for nano-enabled solar concentrators QD Soleil announced that the United States Patent and Trademark Office has allowed the company patent claims based on the use of nanostructures for solar concentrators. Solar concentrators magnify the sun’s rays on a small area of highly efficient solar cells. Such concentrators can dramatically reduce the cost of solar energy systems because the active solar cells can be made much smaller and thinner. Concentrator technology can be used in traditional utility-scale solar farms in addition to novel window glass applications, where the window tinting can be used to generate electricity by integrating a PV cell at the glass edge. QD Soleil uses its quantum dot technology to efficiently capture and concentrate light in a very narrow band at the edge of the glass. The properties of quantum dots make them particularly well suited and superior to other approaches for light concentration, such as organic dyes, which have short lifetimes. http://www.qdsoleil.com

Ascent Solar manufactures lightweight flexible 5-meter CIGS based PV laminate Ascent Solar Technologies, a developer of flexible thin-film photovoltaic modules, announced that the company has manufactured a monolithically interconnected 5-meter long flexible lightweight module on a polyimide substrate. This is the largest monolithically interconnected CIGS module on polyimide and may be the largest of any CIGS module regardless of construction, the company said. The CIGS based thin film material used in this module was manufactured using the company’s 1.5MW roll-to-roll manufacturing line. The module was encapsulated during the testing and qualification of equipment that will be used for its 30MW plant under construction. Based on internal test and evaluation, this 5m long module weighs 2 kilograms and produces 123 watts (under standard test conditions) with an aperture area efficiency of 9.1%. This length is a baseline for the company’s development of large area flexible building integrated photovoltaic (BIPV) products. http://www.ascentsolar.com

Schematic showing the trenches cut into the layered semiconductor. The quantum dots are represented by the circles


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Solarmer Energy makes progress in flexible solar panel development Solarmer Energy presented its progress in flexible solar panel development. Solarmer’s flexible plastic solar panels, made using inexpensive organic materials, are lightweight, transparent, aesthetically pleasing, and environment friendly. These key attributes make flexible solar cells ideal for applications such as smart fabrics and building-integrated photovoltaics. For 2009, Solarmer’s focus is on commercializing and manufacturing their low-cost, lightweight, flexible solar panels, beginning with making samples of these panels available to potential customers beginning this September. The pilot line target completion date is March 2010. http://www.solarmer.com

Solarmer Energy announces leading efficiency results for organic photovoltaics Solarmer Energy presented their new independently verified top-end efficiency of 6.31%. Solarmer, whose focus is on the development and manufacture of plastic solar cells that are translucent, flexible, and lightweight, is extremely pleased with these results. “We’re hoping to generate a lot of excitement with this recent break-through,” says Solarmer’s President Woolas Hsieh. “It gives me confidence that we will have commercial products on the market in 2010.” The 6.31% efficiency of organic photovoltaics (OPV) was independently verified by the Dr. Zadoyan group in the Technology and Applications Center at Newport Corporation. This accomplishment is evidence of Solarmer closing in on their commercial grade module goals of 6.2% efficiency, 3 years half lifetime, and 100cm2 total active area. http://www.solarmer.com

PNNL and Vitex develop process to help protect flexible solar power panels A transparent thin film barrier used to protect flat panel TVs from moisture could become the basis for flexible solar panels that would be installed on roofs. The flexible rooftop solar panels – called building-integrated photovoltaics, or BIPVs – could replace today’s solar panels that are made with rigid glass or silicon and mounted on thick metal frames. The flexible solar “shingles” would be less expensive to install than current panels and made to last 25 years. Researchers at PNNL will create these flexible panels by adapting a film encapsulation process currently used to coat flat panel displays that use OLEDs. The work is made possible by a Cooperative Research and Development Agreement recently penned between Vitex Systems and Battelle, which operates PNNL for the federal government. Researchers at Pacific Northwest National Laboratory (PNNL) developed the thin film technology in the 1990s. At the time, the lab’s team investigated 15 possible applications, including solar power. Vitex licensed the technology from Battelle in 2000 and focused its initial efforts on developing the ultra-barrier films for flat-panel displays. Now PNNL and Vitex are taking a second look at solar power. The encapsulation process and the ultra-barrier film (Barix Encapsulation and Barix Barrier Film, respectively) are already proven and effective moisture barriers. But researchers need to find a way to apply the technology to solar panels. The agreement also calls for researchers to develop a manufacturing process for the flexible panels that can be readily adapted to large-scale production. If successful, this process will reduce solar panel manufacturing costs to less than $1 per watt of power, which would be competitive with the 10 cents per kilowatt-hour that a utility would charge. http://www.pnl.gov http://www.vitexsys.com

Cytec Industries and IMEC collaborate to extend the lifetime of organic solar cells US specialty chemicals and materials group, Cytec Industries, has teamed up with IMEC, a leading European nanoelectronics research center, to commercialize enabling technologies for extended-lifetime organic photovoltaic devices. The two-year initiative is co-sponsored by the Institute for the Promotion of Innovation by Science and Technology, Belgium, according to optics.org. To date, the bulk of the international research effort on organic solar cells has focused on increases in conversion efficiency. However, the operational lifetime of organic solar cells must also be improved to beyond five years – now being tackled by Cytec and IMEC. IMEC unveiled plans for a €70m expansion of its R&D facilities. The investment will fund an extra 2800m2 of laboratory space to support research on 22nm CMOS. http://www.imec.be


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OLEDs highlight Display Week

by Joe Runde

With almost 30 years working on new technologies and new technology products, Joe Runde has been involved with OLED since 2000. He managed public relations efforts for Kodak’s consumer digital products and, earlier, Kodak’s professional products, including the first digital camera. He holds a Ph.D. in English from the Pennsylvania State University.

OLEDs permeated the Society for Information Display’s 2009 International Symposium, Seminar, and Exhibition in San Antonio in early June. The growth and influence of organic lights-emitting diodes was clear both on the exhibition floor, with numerous display and lighting products and prototypes, and in the sessions, with 87 technical papers, many in the category of “invited” with special awards. The poster session added 39 OLED presentations.

“Although the event was down in numbers of both attendees and exhibits, the OLED community is quite optimistic with a record number of displays and lighting devices in numerous exhibits,” said Barry Young, Managing Director, OLED Association. “In all, the future of OLED technology appears stronger than ever.”

Association members, eMagin, Corning, Ignis Innovation, Kodak, Novaled AG, Samsung Mobile Display (SMD), and Universal Display Corporation (UDC) showed a wide range of state-of-the-art products.

eMagin – the leader in near eye displays showed the industry’s highest resolution microdisplay and tightest pixel density.

0.44-inch SVGA 3DS 800x600xRGB white plus CFA; 11 μm pixels 0.61-inch SVGA+ 852x600xRGB white plus CFA 0.77-inch SXGA 1280x1024xRGB white plus CFA achieving 90% NTSC with 1000:1 contrast ratio

Corning – Showed their glass substrates using single crystal silicon that enables manufacturers to get the benefits of high mobility, uniformity and reliability, which they believe will significantly increase performance and yields while reducing system cost.

Ignis Innovation – Demonstrated the use of amorphous-silicon (A-Si) backplanes and voltage compensation, TFT compensation, and efficiency compensation as a backplane for AMOLED displays.

2.2-inch 320x240, 200 cd/m2, 100K:1, 50,000 hr 4.8-inch quad RGBW, 288x154, 500 cd/m2, 100K:1, 75,000 hr; same dot-pitch as 32-inch LCD

Kodak – showed a new innovation in lighting control, which allows light to be directed at a 90o angle to increase brightness in high ambient conditions.

6-inch lighting panels featuring color rendering >85% 5-inch RGBW display, with sRGB blue, 380 cd/m2 peak illumination, 370-μm pitch

Novaled, AG – showed their latest results PIN OLED technology and Thin Film Encapsulation of OLEDs, yield improvement for singlet and triplet emitters with lifetimes up to 110 thousand hours at efficiencies up to 50 lm/W as used in lighting applications.

Universal Display Corporation – showed their phosphorescent technology.

4-inch flexible monochrome on metal substrate, 320x240, 100 cd/m2 at full white, 1000:1, 0.3 mm thick

2-inch sample lighting panels in red, green blue and white


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Samsung Mobile Display (SMD) – showed a wide range of AMOLED displays including transparent, flexible, curved and touch capabilities as shown in the next Table. Highlighting the demonstration was 14.1-inch and 31-inch TVs. SMD also showed their first OLED Lighting prototypes, built on 200x200mm glass, with 90% uniformity and luminance of 3,000 cdm2. The full range of Samsung’s OLED display offerings is summarized in the following table:

The Seminar also featured exhibits by a number of other OLED companies, including LG Displays, which showed 15- and 19-inch panels; Merck showing Merck-DELO encapsulation proven in tests at 85ºC/85%RH for 1000 hr; OLED materials for solution and vapor deposition; SAES, which makes getters for flexible OLED manufacture with newly developed transparent layer that can be applied through UV or thermal curing; Add-Vision, demonstrating printed flexible monochrome OLED displays and lighting, using a low-cost manufacturing process readily scalable to production levels; Fraunhofer, showing 320x240 monochrome bidirectional OLED microdisplay with a 4x3 array of photodiodes for imaging eye position: Aixtron, which has OVPD implemented up to Gen 2 and up to Gen 3.5 (650x780 mm), with an approach that provides 60% materials utilization; SimTec, demonstrating their SimOLED simulation software for LED design; Daou Xilicon, which offers OLED manufacturing simulation, including mask editor, structure generation, and optical simulation; and Sunic, featuring thermal deposition equipment that supports substrates up to 370 x 470 mm.

About the OLED Association (OLED-A): OLED-A provides a forum for the interchange of technical and market information. Its membership includes companies involved in small-molecule OLED technology and polymer technology (PLED or light-emitting polymers), as well as supporting technologies, as well as companies incorporating OLED displays and light sources into their products. OLED-A serves its membership by fostering the more rapid development of OLED technology and OLED products; serving as a resource on OLED markets and products for media and investors; functioning as a catalyst in the development of standards for OLEDs; and providing a forum to promote and market OLED technology products. http://www.oled-a.org


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Pictorial Summary of Flexible Displays at SID

Thanks to Jurgen Daniel from PARC for capturing many of the highlights from SID related to flexible display technologies that were showcased at SID.

This year’s attendance at SID was significantly lower (~50-60% of previous years) and the exhibit was considerably smaller. Attendance was about 3070 attendees. Attendance was down for a variety of reasons, including concerns about the “swine

flu”, the weak global economy, competing conferences (e3, Computex, Dimension3, etc), and uncertainty about the appropriateness of the San Antonio location. There were 92 oral presentations, 18 late news presentations, and 201 posters.

Numerous eBooks were showcased based on E-ink’s electrophoretic media. E-ink’s new developments included a full color touch screen, video capability, advanced black and white, and new inks boasting >45% white and > 20:1 contrast ratio.


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Kent Display showed off their cholesteric liquid crystal technologies including electronics skins, a moldable, conformal display. The LCD layer measures about 4 microns on a thermoplastic substrate, which is much thicker. Kent showed off a

mobile phone casing that could change between 8 different colors at the push of a button.

ASU’s Flexible Display Center showed (on the left) the lamination of a flexible substrate to rigid carrier during processing. On the right is Fujitsu’s e-Book which showcased color, 175ppi, on a plastic substrate, using stacked

(RGB) cholesteric liquid crystal requiring several passes for full saturation.

LG Display showed a 3.0-inch transparent AMOLED (on the left), a 3.0-inch micro-thin AMOLED that measures only 0.42mm thick (center), and UDC showed a full-color, video-capable, flexible AMOLED (right).


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LG Display showed off a full-color 6.0-inch reflective LCD for eBook applications and Qualcomm showed off their mirasol color reflective display solution in a 2.2-inch format.

Sharp presented a polarizer-free reflective LCD (50% reflectance, 20% reflectance for color – at 10:1 contrast ratio), using only 10 microWatts power consumption. Sony presented a solution processed (pentacene, PVP-OTS)

OTFT/OLED display that uses low-cost copper lines.

On the left, adt/University of Pforzheim showed displays for indicator/billboard applications with micro-fluidic structures and electrowetting. On the right, Samsung (jointly with Bundes Druckerei) showed a bendable AMOLED electronic ID card.


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Samsung showed a 31-inch FHD AMOLED LTPS TFT, bottom emission OLED that measured 8.9mm thick.

On the left is a 2.0-inch flexible OLED from Samsung. On the right is Samsung’s AMOLED “free flapping” 4.0-inch display (480x272 pixels) that measures 50 micron thick and is comprised of a color filter + OLED.

Samsung showed a 12.1-inch transparent AMOLED based on LTPS and top-emission. On the right, Corning showed off a thin flexible (0.1mm) glass, and other glass products, including versions with etched holes.


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SID Display Week Symposium 2009 June 2-5, San Antonio, Texas

There were almost 100 papers or posters this year covering flexible displays from companies and universities alike, a considerable increase on 2008. In this first report, Phillip Hill covers all the

papers from day one of the symposium: Sharp Laboratories of Europe/Sharp Corp., Kent Displays, Add-Vision, Sony, iRex Technologies, Samsung Mobile Display, Universal Display

Corporation/LG Display/L3 Communications, Prime View International, Polymer Vision, Versatilis, LG Display, University of Illinois, AIST/Japan Chemical Innovation Institute/Konica Minolta

Technology Center/Toppan Printing/DIC Corporation/ADEKA Corporation, and IMEC

Ultra-Thin Chip Packaging (UTCP): a Promising Technology for Future Flexible Display Interconnection Jonathan Govaerts, Wim Christiaens, and Jan Vanfleteren, IMEC, Ghent, Belgium

With several flexible display technologies coming to the fore, driving electronics seem to become the limiting factors to the bendability of any flexible display system. The idea of adapting existing interconnection technologies is discussed in this paper. Ultra-thin chip packaging is proposed to bypass the limitation imposed by the rigidity of the driver electronics. A novel packaging technology has been developed at IMEC, the so-called UTCP, or ultra-thin chip packaging technology. Basically, it consists of embedding the thin chips in between two layers of polyimide (PI), a high-quality plastic that can withstand relatively high temperatures, 350°C and more. One variant was investigated in the frame of the European project FlexiDis – aiming to develop several possible technologies for industrially manufacturing flexible active-matrix displays. Initial trials have been conducted to transfer the UTCP technology to functional driver chips as well. The chips used were slim display driver chips (approximately 1.5x22.5mm), more specifically the eDrive021, a 320-output dot-matrix display driver developed by ST Microelectronics for e-paper applications.

Pictures of the first results of UTCP packaging with functional (driver) chips from ST Microelectronics


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High Resolution Flexible Electrophoretic Display by OTFTs with Inkjet Printed Organic Semiconductor Noriyuki Kawashima, Norihito Kobayashi, Nobuhide Yoneya, Hideki Ono, Toshio Fukuda, Takahiro Ohe, Yui Ishii, Akihiro Nomoto, Mari Sasaki, and Kazumasa Nomoto, Sony Corporation, Kanagawa, Japan

A 4.8-inch 480x640 (167 ppi) organic thin-film transistor (OTFT) driven flexible electrophoretic display has been demonstrated by developing inkjet printing of a small-molecule organic semiconductor (OSC) peri-xanthenoxanthene derivative. A passivation layer of OSC was also printed by the screen-printing method. Pixel OTFTs exhibited high mobility of 0.4cm2/Vs and high thermal stability after full integration of the field shielded pixel structure. The Figure below shows a schematic cross-section of the developed field shielded OTFT pixel with bottom-gate bottom-contact structure. During fabrication, Cu gate electrodes and the storage capacitor electrodes are first patterned by photolithography on a 200-μm thick polyethersulfone (PES) substrate. A polymer gate insulator with a thickness of 550nm was then spin coated and annealed at 150°C. After patterning of Au source-drain electrodes and the hydrophobic bank by photolithography, the OSC layer was patterned by inkjet printing under ambient conditions.

On the left is a schematic cross-section of the OTFT pixel; on the right is an image of inkjet printed OTFT-driven EPD

A Variable Curve Backlight David J. Montgomery, and Harry Walton, Sharp Laboratories of Europe, Oxford, England Takeshi Ishida, and Yusuke Tsuda, Sharp Corporation, Nara, Japan

A new backlight was presented for flexible applications. The backlight maintains central brightness and on- and off-axis uniformity performance as a normal backlight, but at a large range of curvatures and shapes, from flat to 50mm local curvature. As LCDs are a transmissive technology, a backlight is generally required in some form for its operation. When typical constructions of mobile LCD backlights are curved beyond a certain radius, the uniformity and brightness of the backlight change significantly. Addressing this problem is of equal importance as the display to the operation of proper curved LCD.

A comparison photograph between the experimental sample with a display and the same display with a typical backlight is shown in the figure. The displays are curved to 100mm radius of curvature. The photograph is shown off-axis to illustrate the extent of the non-uniformity and the correction in the new experiment. The new backlight can be used with a (one or two dimensionally) shaped LCD whose shape is not known when the backlight is designed. The backlight maintains substantially the same brightness, apparent uniformity and angular properties as a flat typical backlight and numerous curvatures and shapes are possible, both convex and concave, even if the local curvature is substantially less than the distance of the viewer to the display.


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The backlight can be made on a single production line to satisfy multiple display curvatures and styles, greatly reducing the costs of developing high volume products and samples. The backlight is no larger or thicker than a typical backlight, consists of no more components, and is not required to be attached to the display. The backlight is made with existing processes and light sources and does not require exotic or unusual materials. The principle is size independent and can be applied to any size display for any application. In principle, the backlight can also be adapted to fully flexible operation.

Flexible Electronic Skin Display Erica Montbach, Oleg Pishnyak, Mark Lightfoot, Nick Miller, Asad Khan, and J. William Doane Kent Displays Inc., Kent, Ohio

“Reflex” electronic skin displays can be conformed to cover the electronic consumer devices allowing the consumer to instantaneously switch the case color electronically. These displays have inherent reflective color and an ultra thin and flexible form factor. The bistable, reflective cholesteric liquid crystal (ChLC) display technology from Kent Displays, branded “Reflex” displays, has high brightness, low power consumption, excellent viewing angle, and is ultra flexible. Recently, an electronic skin has been introduced utilizing the inherent color and grayscale of the Reflex technology. The optical properties of electronic skin displays have recently been dramatically improved. The consumer device markets, particularly cell phone markets, require high storage and operating temperatures while desiring specific color combinations. Tuning of process conditions and alternative materials have allowed for many of the optical targets to be achieved. In addition, the ability to have switchable color conforming to the bends and curves of consumer electronic devices is highly desired. The photo illustrates an electronic skin display conformed to a complex curvature, where two dimensions are simultaneously curved, similar to a spherical type shape. Previously electronic skins conformed to simple curvatures. A simple curvature is when only one dimension is curved resulting in cylindrical type shape. A display conformed to a complex curvature has the advantage that it can cover curves, bends, and even corners on a device case. The display in the photo was thermoformed to a complex curvature and is electronically switchable after forming.

Demonstration sample of the variable curve backlight and a typical backlight

Multiple photographs of the same thermoformed electronic skin switched to different colors. This

three-layer display is formed into a complex curvature.


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Development of E-paper Color Display Technologies Alex Henzen, iRex Technologies, Eindhoven, The Netherlands

Electronic paper devices based on electrophoretic layers, large or small, are for now limited to grayscale reproduction of (semi)static information. For the present, this will be acceptable. However, the longer term will require ever more and better colors. The final goal must be a color image that challenges the performance of a color photograph. This paper describes the technical challenges and possible solutions. Electrophoretic displays are the base of today’s electronic paper development. Basically, the display technology provides a grayscale switching platform that can be used to display grayscale information. Today’s display quality compares to a reasonable quality newspaper: moderate contrast (~8:1) on a light gray background. Theoretically, therefore, it would seem the transition to color would lead to a newspaper-like color performance. Unfortunately, this is not the case. Where newspapers use subtractive color mixing, leading to a white level equal to the one provided by the paper it was printed on, electrophoretic based displays rely on additive color mixing, providing, at best, half the e-paper brightness (now 42%), at reduced color reproduction.

Henzen looked at multi-layer additive color mixing. It is by no means impossible that EPDs could reach near 100% reflectance. However, beyond the 60% point, a fundamental change in the optics will be necessary. Also, sub-pixelation intrinsically leads to reduction of reflectance. One display technology may try to jump into this gap, providing additive color mixing without sub-pixelation: cholesteric displays (see illustration). These solve the sub-pixelation issue by layering the primary colors instead of displaying them side by side. They show the promise of high reflectivity and, if applied correctly, convincing color performance.

If the technology can solve the “maturity gap” (from sample to mass production at reasonable cost), and make the transition to active matrix or find another way to eliminate the disadvantages of “line by line” addressing, we may see commercial e-paper with stacked cholesteric color displays within a few years. At this moment, multi-layer cholesteric displays show reflectivity at ~30%, and will suffer slightly from the lower aperture of active matrix panels, but the promise of a 25% reflectance at good saturated color performance seems worth pursuing.

Henzen then looked at subtractive color mixing. There are more options eliminating sub-pixelation by using multiple layers. One was reported on by Philips last year, and uses “in plane” electrophoretics, and also LiquaVista’s multi-layer electro-wetting displays, where pigments are moved into the field of view in front of a white reflector. If done with high aperture ratio and high reflectance background, this could theoretically outperform cholesteric displays. The benefit lies in the subtractive color mixing. Contrast ratio is less important than in the case of sub-pixelated color displays: color purity is almost exclusively determined by each single pigment, and cross-contamination should be close to negligible. A contrast ratio of around 20:1 should be sufficient for good, saturated colors.

The future will show alternative e-paper technologies to reach full color reproduction. The cost for this innovation will be high, and color devices will initially be expensive. An alternative in the form of additive color (color filter) devices has a legitimate place in this market if color purity is less important. The differentiator will be price: grayscale and color filter displays will be inexpensive, leading to low cost e-readers, whereas premium prices must be paid for the highest performing devices.

Three-layer cholesteric color display


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40-inch FHD AMOLED Display with IR Drop Compensation Pixel Circuit Yang Wan Kim, Won Kyu Kwak, Jae Yong Lee, Wong Sik Choi, Ki Yong Lee, Sung Chul Kim, and Eui Jin Yoo Samsung Mobile Display, Chungcheongnam-do, Korea

Samsung Mobile Display has developed a full color 40-inch FHD AMOLED display, the largest OLED display ever reported to date. It is based on the technologies of low temperature polysilicon (LTPS) TFT backplane using super grain silicon (SGS) crystallization, and a power line IR-drop cancellation pixel circuit. The panel points to large-size and high-resolution AMOLED panels in TV applications. The display has 40-inch diagonal size with FHD resolution, and a sub-pixel size of 151x453µm. They applied a new crystallization method (SGS) and a conventional shadow mask to deposit small molecule OLED material onto TFT substrates by thermal evaporation. The developed AMOLED shows good image quality and a large color gamut. It shows perfect compensation for gradual luminance difference by using an IR-drop pixel circuit.

Multi-wavelength Photolithography for Manufacturing Flexible Electronics Ajay Jain, and George Powch, Versatilis, Shelburne, Vermont

A novel method of intrinsically self-aligned photolithography is presented for cost effective manufacturing of polysilicon AM TFT arrays with integrated drivers on large area, flexible substrates, suitable for eventual R2R processes. Multiple patterns are exposed simultaneously into multi-wavelength sensitive photoresist layers, where all critical coatings have been pre-deposited, fully obviating repetitive masking steps. The method can significantly reduce processing time and the associated capital costs while increasing quality and yield. Under DARPA’s “Macroelectronics” program, Versatilis sought to develop a self-aligning photolithography method avoiding all alignment and registration challenges, and which could enable silicon circuit features capable of 1GHz performance on very flexible substrates for potential applications such as phased array radar rollable into a soldier’s backpack, as well as enabling flexible displays with high speed polysilicon TFT arrays and integrated drivers for real time video in very lightweight form factors. The researchers developed a novel form of multi-wavelength photolithography that fully obviates the repetitive sequence of deposition, mask, expose and etch for the critical layers of typical TFT circuits, and eliminates the substantial associated costs; they manufactured high temperature polysilicon TFT arrays, and 21-stage ring oscillators operating to 500MHz, on approximately 180x360mm stainless steel foils in a simulated R2R manufacturing process. All the critical coatings of, for example, a typical TFT array and associated driver circuits, are pre-deposited as a straightforward unpatterned stack, then followed by multiple layers of photoresist where each


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layer is sensitive to a different wavelength of light: latent images are then captured in the photoresist layer(s) either simultaneously or sequentially by selective exposure to the appropriate activation wavelengths, then sequentially etched to reveal multi-level structures (see illustration on prior page).

Wearable 4-inch QVGA Full Color Video Flexible AMOLEDs for Rugged Applications Ruiqing Ma, Kamala Rajan, Jeff Silvernail, Ken Urbanik, Jason Paynter, Prashant Mandlik, Mike Hack, and Julie J. Brown, Universal Display Corp, Ewing, New Jersey Juhn S. Yoo, Yong-Chul Kim, In-Hwan Kim, Seung-Chan Byun, Sang-Hoon Jung, Jong-Moo Kim, Soo-Young Yoon, Chang-Dong Kim, and In-Byeong Kang, LG Display, Gyeonggi-do, South Korea Keith Tognoni, Robert Anderson, and David Huffman, L3 Communications, Alpharetta, Georgia

The researchers presented work on the world’s first wrist worn communication device built upon a flexible low-power consumption full-color AMOLED using phosphorescent materials. The device offers the wearer the ability to see high information content video rate information in a thin and rugged form factor 4-inch 320x240 display, conformed around a human wrist. The paper presents work on developing a high information content full-color wearable display wrist device. It focuses on the flexible AMOLED backplane and front plane, mechanical packaging and drive electronics development. The low power consumption PHOLED and flexible OLED technologies allow the display to be conformed around a human wrist offering the first demonstration of a wearable OLED communication device. The flexible AMOLED display developed for this unit combines an innovative flexible amorphous-silicon backplane with a high-efficiency PHOLED, thin film encapsulation and conformal lamination frontplane technologies. The 4-inch full-color video prototype is only 0.3mm thick and consumes less than 1W at 100cd/m2 full white. They addressed the challenges in mechanically packaging and driving such a display device to ensure its suitability for rugged applications. They have thus successfully built the first wearable AMOLED display wrist unit which can show static and high information content full-color video images.

On the left is the 4-inch flexible AMOLED panel under bending; on the right is a prototype of the wearable display wrist unit

Development of TFT Process and Circuit Integration on a Flexible Substrate to Enhance Flexibility Chang-Dong Kim, Soo-Young Yoon, Sang-Hoon Jung, Juhn-Suk Yoo, Jong-Kwon Lee, Yong-In Park, In Byeong Kang, and In-Jae Chung, LG Display, Paju, South Korea

To make real flexible displays, there are several key technical issues, such as the robust backplane process on flexible substrates and removing rigid electronics. In this paper, the researchers summarize recent technical approaches and results on these two issues. In the flexible manufacturing processes, they have developed two kinds of processes: “bonding-debonding” and “single plate”. In the bonding-debonding process, flexible substrates are bonded on conventional glass substrates and carried with the glass substrates for the conventional a-Si thin film


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transistor process. It is easy to apply this to small- and middle-sized displays. However, there is still a thermal process limitation at below 150°C due to the adhesive layer itself between the flexible substrate and carrier glass and it is difficult to upscale to over a Gen 2 line for mass production. On the other hand, the yield of the single plate process comes to the level of mass production by overcoming the problem of carrying over the thick single plate substrate. Only one etching step to make substrates thinner is added after forming the TFT array using the single plate process. For implementing a truly flexible display, all components of the display module, such as gate driver IC, control printed-circuit board (PCB) and source tape-carrier package (TCP), should be removed or replaced with flexible components. Recently, integrated gate drivers using a-Si TFTs have been widely used on AMLCDs. Therefore, the gate driver IC can be successfully removed by using integrated gate drivers’ circuits. The rigid PCB can be replaced by flexible printed circuits for panel driving. They fabricated a 4-inch 320x240 AMOLED display with increased flexibility on a stainless steel substrate. An a-Si:H gate scanning circuit was employed for the gate driver in order to increase flexibility in the vertical direction of panel. And TCP and a flexible circuit board were used. As a result, the AMOLED module has a bending radius of less than 5 cm along one axis.

Flexible E-books Ian French, Prime View International, Brighton, England

The first generation of e-books used glass-based TFTs for active-matrix multiplexing. These had good optical performance and benefited from using the same manufacturing infrastructure as TFT LCDs. Prime View has now developed flexible e-books that are lighter and more robust and which are manufactured using most of the same equipment and processes. Like many other groups, Prime View has been developing flexible electronic paper displays (EPDs) primarily for use in e-books, but with many other possible applications once a manufacturing base has been developed. This may seem surprising since high quality glass EPDs are already in volume production and have achieved widespread acceptance in e-books. The first section explains why the company is developing flexible EPDs for use in e-books, e-newspapers and small signs. Following that, French describes the company’s EPLaR method of making plastic displays and how they are being developed in a standard TFT LCD factory. He then shows how the performance of EPLaR TFTs and displays is the same as ones made on glass substrates. Finally he presents his conclusions and comments on the future directions of EPLaR. One of the advantages of reflective displays is that their optical performance is not affected by the optical characteristics of the underlying substrate. This means that colored plastics with poor transmission can be used for the substrate. Larger displays, such as the EPLaR 9.7-inch display (see photo), will be used for electronic newspapers, e-books and e-textbooks. Prime View has shown that the electrical characteristics and stability of TFTs on laser-released plastic substrates are effectively the same as TFTs made on glass. This means that EPLaR TFTs will have the high performance and high reliability that has been demonstrated in LCD displays in many millions of LCD TVs, laptops, mobile phones, etc. In the future Prime View will benefit from further improvements in electrophoretic display technology, such as the development of full-color displays and video rates, which will also be applicable to EPLaR displays. 9.7-inch EPLaR display

Cross-sectional view of a-Si:H TFT on stainless steel substrate


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Rollable Displays: From Concept to Manufacturing Edzer Huitema, Fred Touwslager, Erik van Veenendaal, Nick van Aerle, and Pieter van Lieshout Polymer Vision, Eindhoven, The Netherlands

A rollable 320x240 display is presented that is integrated into a pocketable e-reader product. The paper describes a 254ppi monochrome and a 130ppi color display that are rollable to a radius of 6mm. Rollability requires extreme flexibility and mechanical integrity of the layer stack. One of the key parameters for rollability is the display thickness, which has been reduced to 0.1mm. This is more than 10x thinner than the typical thickness of glass-based displays and more than 3x thinner than currently developed flexible displays. Two new display modules have been developed: a rollable monochrome high resolution module (254ppi) and a color module with the highest reported white reflectance of 24% (see photo). The latter is the world’s first rollable color display. Both modules use the same backplane. Besides resolution and color the bending radius of the displays was also reduced to 6mm.

Flexible/Stretchable Electronics for Unusual Display Systems John A. Rogers, University of Illinois, Urbana, Illinois

Organized arrays of single crystalline semiconductor nanoribbons, nanomembranes and nanowires represent an enabling class of thin film type material for flexible/stretchable circuits suitable for display and other applications. This paper describes methods to create and manipulate such materials. The inorganic semiconductor building blocks for the systems described here can be created either by anisotropic etching of bulk wafers of material or by use of sacrificial layers in multi-layer stacks grown on wafers. The photo shows arrays of silicon ribbons printed onto a sheet of plastic, and representative CMOS circuits formed with such materials on a rubber substrate. Here, the ribbons (typical thicknesses <300nm) function in the same manner as vacuum deposited silicon in conventional systems, such that completed circuits can be formed using thin film deposition and patterning techniques similar to those in current use. Printing-like integration schemes and inorganic semiconductor nanomaterials provide routes to high performance electronic systems on non-wafer substrates, ranging from flexible sheets of plastic to stretchable slabs of rubber to rigid plates of glass. These approaches might find applications in systems that cannot be addressed with established technologies. The practical value of such methods will be, of course, a function of the characteristics of the associated manufacturing tools. Developing the supporting technologies is a subject of current work.

Image of a bent sheet of plastic with printed silicon nanoribbons in sparse arrays (left), and a stretchable CMOS silicon integrated

circuit on rubber, in a twisted configuration (right)

a) A high-resolution rollable display module; b) The first ever rollable color module


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Polymer Network LCD Driven by Printed OTFTs on a Plastic Substrate K. Yase, AIST, Ibaraki, Japan; H. Yonehara, Japan Chemical Innovation Institute, Tokyo, Japan; K. Matsuoka, Konica Minolta Technology Center, Tokyo, Japan; O. Kina, Toppan Printing Co., Ltd., Tokyo, Japan; M. Koutake, DIC Corporation, Tokyo, Japan; K. Noda, ADEKA Corporation, Tokyo, Japan

The group prepared organic thin-film-transistor arrays with large area and high precision, with 6-inch diameter and 200ppi, by using a micro-contact printing (μCP) method. They succeeded in driving a polymer network liquid crystal display (PNLCD). Organic electronic device fabrication by wet processes using organic semiconductors, insulators, metal nanoparticles, etc., attracts a great deal of attention. In particular, by utilizing printing techniques and plastic substrates, flexible electronic devices of large area and low-cost can be attained. However, conventional printing techniques such as flexo printing, screen printing, and inkjet printing have printing resolutions of only 30μm or larger, which is not enough for TFT displays. μCP, first demonstrated in 1994, has an advantage of high-resolution printing of self-assembled mono-layers in sub-micron order. The researchers have developed a printing technique based on μCP and have already reported the fabrication of fine patterned OTFTs of large sized areas. In this latest study, they developed PNLCD devices using these OTFTs, and succeeded in driving the display. TFTs with various channel lengths and widths were fabricated onto a 150mm-squared polycarbonate film (see photo).

The TSP-μCP method has proved to be useful for fine patterning of silver nanoparticle electrodes and a semiconducting layer for OTFT. The obtained OTFTs exhibited the mobility and on/off ratio on the order of 10-

3cm2/Vs and 107, respectively. Passivation and light blocking layers provided enough stability against exposure to light and air. They were also found to take a role in preventing chemical and mechanical degradations of the active components. PNLCD operation demonstrates that the OTFT arrays fabricated by this method already meet a practical need, the researchers say.

Printed, Doped, Flexible P-OLED Displays and Lighting Devin MacKenzie, Janie Breeden, Jianping Chen, Phil Hinkle, Eric Jones, Anoop Menon, Yuko Nakazawa, Joon-Ho Shin, Vung Vo, Matt Wilkinson, Yuka Yoshioka, and John Zhang, Add-Vision Inc., Scotts Valley, California

Add-Vision (AVI) has brought a new perspective to OLEDs based on doped organic semiconductor device chemistries and air stable cathode technology to enable low cost printing tools and flexible, lamination encapsulation. It enables advantages for new printed electronics opportunities outside of conventional high-resolution display applications, and complex and high capital cost processing. Using simple large-area printing tools enabled by doped light-emitting polymer and cathode inks, AVI has developed a flexible display technology that provides low capital cost, entry level manufacturing capabilities in the near term for flexible OLEDs. This technology has emerged from the feasibility level, to >5,000 hour lifetime, low voltage, flexibly encapsulated devices, which are being transferred into pilot manufacturing. This has resulted from a combination of doped light emitting polymer chemistry developments, cathode materials and process improvements, print process optimization and extensive encapsulation materials and process development.

At the same time there is significant activity in product prototyping and development in conjunction with AVI’s partners and end customers. AVI intends that that this work will have a significant commercial impact as it provides a route to early commercialization of printed active electronics and flexible OLEDs. Furthermore, it may have significant benefits for the organic electronics and flexible display technology ecosystems. By stimulating scale-up of supplies of active layer materials, flexible barrier substrates, and process tooling, the materials and tool

Images of the test TFT and the 100ppi TFT array


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supply industries can increase production scales, reduce costs, improve quality control and increase overall availability. By taking a different process and applications focus than most other OLED efforts that have been working toward high end, TV and general illumination applications, the company says that it provides an alternate path to widespread adoption of OLED technology in flexible applications.

Top: A top view of a light-emitting polymer ink being printed through a screen stencil mask on a development printer at AVI. Bottom: A fully-printed doped OLED device substrate immediately after cathode layer printing. This mask set includes keypad

backlight, segmented and digital content panel, and test patterns in the same print sheet.

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3D displays Display standards High resolution displays Touch screens Flexible displays

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Smart Fabrics Conference March 10-12, 2009, Rome, Italy

Phillip Hill covers presentations from Intertech/PIRA’s Smart Fabrics Conference given by Clothing Plus, Atelier Fede, EU Commission, CeNTI, Ohmatex, University of Pisa (x2), Dublin City University, and TITV

Clothing Plus Sensors: Comfortable Sensor Systems Akseli Reho, Clothing Plus, Jämintie, Finland

The company’s vision is to implement comfortable sensor systems: the clothing and textile approach gives a natural platform for sensing people. Application areas are sport, well-being, rehabilitation, occupational health, and healthcare. The strengths of textile sensors are that they are natural to put on and comfortable to wear; they are invisible and an easily accepted way to wear sensors. Correct sensor placement is solved with carefully designed clothes or accessories. The required cables between the sensors and other electronics can be integrated into the textiles too. Textile sensor belts have been on the market for six years. The next step is sensoring underwear. The bra is a perfect product for the integration of sensors. Reho went on to describe the “Polar AE” product to be used in underwear measurements. It is a generic component for mass customization through integration in textile factories with existing machines and processes. Textile sensor systems require modern technologies: laser cutting, lamination technologies (silicone and film, heat and RF-lamination), ultrasonic welding, conductive fibers, and plastics.

Wearable Microsystems and Smart Textile Systems: Present and Future R&D under the EU Information and Communication Technologies Programme Andreas Lymberis, European Commission, Brussels, Belgium

Lymberis outlined the European strategy and implementation for RTD and innovation; smart fabrics and interactive textiles under the R&D program of the EC; opportunities for funding; and EC initiatives and support for technical textile and clothing. He went into details of the various EU projects in the field. OFSETH (Optical Fiber Sensors Embedded into technical Textile for Healthcare) is for the monitoring of cardiac and respiratory activity for patients submitted to magnetic resonance imaging who need continuous care. PROETEX (February 2006 - January 2010) covers micro-nanostructured fiber systems for emergency disaster wear. STELLA (January 2006 - January 2010) stands for stretchable electronics for large area applications in health care. The stretchable electronics includes energy supplies, sensor and actuators, and display and switches. BIOTEX (September 2006 - May 2008) was for bio-sensing textiles to support health management. It developed biochemical sensing techniques and integration on fabric substrates; and developed sensing patches for the monitoring of body fluids (sweat rate, pH, electrolytes).

Textile sensor belts currently on the market


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ConText (January 2006 - June 2008) covered contact-less sensors for body monitoring incorporated in textiles. It developed capacitive textile sensors for electro physiology, and integration of electrodes, electronics and wiring in textiles.

There is currently a modest market size for wearable computing and smart fabrics and interactive textiles (SFIT). But there is a strong future outlook with players including Philips, Invista, Siemens medical Solutions Health Services, Infineon, Santa Fe Sciences and Technologies, Vivometrics, BodyMedia, Sensatex, and Smartex. SFIT was a $340 million industry in 2006 with a growth rate of 19% annually, and projected to reach $720 million by 2008.Lymberis asked why the market is relatively modest so far. There is no industrial supply chain for SFIT products. Textile and clothing industries are not sufficiently engaged. There are no dedicated standards for reliability testing of smart textiles available, and no standardized methods for testing the robustness of sensor systems. Also the research community is fragmented.

I-Jeans: Stone Interactive Jeans Alexandra Fede, Atelier Fede, Rome, Italy,

Alexandra Fede is a “scientific fashion designer”. I-Jeans is a sportswear company providing embedded intelligence to knit, woven or non-woven textile structures. “Stone Interactive” jeans represent the first implementation of a heating platform in a high-end product manufactured on a large scale. The heating platform is smaller, lighter and more flexible than conventional solutions. The jeans offer the comfort of ideal warmth with a heating capacity of up to five hours. The wearer can choose among three different operational modes: either constant heating or one of two pre-programmed, sensor-monitored, temperatures. An LED (as shown in the photo, below left) indicates the selected mode with a single-button control unit. Energy is only supplied when the temperature drops below a pre-set limit at portions of the wearer’s hand that are sensitive to the cold detected by sensors in places inside the glove. Using highly flexible heating elements (see photo, below right), heat is generated selectively within the glove or jeans without restricting movement.

A prototype from the STELLA project


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Novel Technologies in Materials Development for Sensing-actuator Systems Antonio Vieira, CeNTI, Vila Nova de Famalicão, Portugal

The presentation covered inkjet printing technology, tri-component fiber extrusion, nanofibers by electrospinning, polymer multi-layer deposition, plasma pre-treatment, DC dual magnetron sputtering, and wire feed metal evaporation. Potential applications are heat reflective films on textile substrates; biometric sensors printed directly on the fabric surface; deposition of piezo and piezoresistive sensors for wearable electronics applications directly on the fabric surface; high barrier films with high optical transmittance for OLED and organic photovoltaics; plasma functionalization of textile substrates; development of new printed polymeric capacitor systems; development of new printed polymeric solid-state battery systems; conductive and piezoelectric integrated fiber biometric sensors (heart rate monitoring, movement monitoring); textile integrated strain and pressure sensors; conductive fibers for antistatic fabrics and integration of wearables; porous and hollow fiber structures for controlled drug delivery; organic photovoltaic and OLED device integration at fiber level; fiber integrated wearables for personal use (touchpads and sensors); and energy storage and energy generation applications (piezoelectric fibers).

The Cost of Integrating Micro-electronics into Textiles Christian Dalsgaard, Ohmatex, Aarhus, Denmark

Ohmatex is a commercial smart textile development company focusing on the integration, mounting and encapsulation of micro-electronics in textile structures; weaving, knitting and interconnecting conductive textile circuitry; and textile property enhancement on a nano scale. It is a self-financed private company established in March 2004 with three full-time staff plus freelancers. Since 2005, Ohmatex has designed and developed a variety of conductive textile ribbons and elastics. Laser techniques are used to remove textile material and insulation on metal filaments. Smart textiles are a gradually maturing market representing an opportunity for technology providers and commercial applications. Potential killer applications are real-time posture monitoring for sport and athletics; early warning systems in protective clothing; safety lighting in children’s and adult garments; and truly wearable health monitoring.

Multi-functional coating technology


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Multisensory Wearable Solutions for Neuromotor Rehabilitation Danilo De Rossi, University of Pisa, Pisa, Italy

Research areas cover body posture and gesture capture, recognition and classification. Applications are rehabilitation, sport, human/machine interaction, e-movies, and e-games. De Rossi went into details on redundant sensor arrays for surface strain mapping, textile-based electrogoniometry, and a sensing glove the university has developed using 20 piezoresistive sensors distributed over the hand joints (see photo). One application is a golf virtual trainer. The main joints involved in a golf swing are covered by sensors and monitored. The system has 32 different sensors. The paper pattern of the catsuit (see illustration) has signal wires (red) and power wires (black) and it has a graphical user interface running on a PDA. An avatar manages all the training tasks, avoids injuries, and corrects wrong movements.

Smart Textiles for Technical Applications Dirk Zschenderlein, TITV, Greiz, Germany

TITV is the Institute of Special textiles and Flexible Materials. It has 56 employees of which 30 are engineers and scientists. It had a turnover of €3.2 million in 2007 funded by German ministries and the EU. The content of the presentation covered smart textiles for technical applications: electrical conductivity – the basis for smart textiles; active heat management – medical and automotive applications; and textile circuits, switches and data buses, sensors and luminescent textiles. The topics covered in the institute’s R&D in textile micro-systems techniques are energy harvesting, textile-based micro-systems and components, integration in flexible substrates, positioning and connection on flexible substrates, embroidery, sewing, and thread technology. On surface modification, the research covers coating, nano, sol gel, hot melt, rolls, coating knives, galvanization of thread and fabrics finishing, dyeing, and printing. On flexible materials, research centers on Jacquard and shedding weaving techniques, Leno technology, rapier and air weft insertion, narrow fabrics, warp knitting, spacer fabrics, and braiding.

LEDs connected with ELITEX conductive threads


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Materials with Switchable Charactersitics: the Key to Innovation and Creativity in Future Fabrics Dermot Diamond, Dublin City University, Dublin, Ireland

Dermot Diamond is a professor at CLARITY: the Centre for Sensor Network Technologies, part of the National Centre for Sensor Research (NCSR). The NCSR has over 250 full-time researchers and support staff. Investments and income since 1999 are now approaching €100 million. The current situation is that wearable sensors are usually discrete sensors and electronic components attached to the fabric. But there is a move to functionalized fabrics such as Lycra coated with conducting polymer that can be used to functionalize discrete locations on a garment; it can sense stretch, bending, pressure, and movements; and it can pick up breathing, heart function, and is innocuous to the wearer.

One market is to track compliance with exercise regimes. In 2000, the estimated healthcare costs associated with physical inactivity were $76 billion. If 10% of adults began a regular walking program, the estimated savings in heart disease costs could be about $5.6 billion. The current status is that sensors are increasingly being integrated into fabrics. Signal/comms/power lines are woven into material using a wide variety of materials. Commercial products are beginning to appear, but functioning systems are still largely based on conventional electronics modules “integrated” into fabric. Diamond said the there was a tremendous opportunity for polymer electronics, sensors and optical components to drive down cost and add functionality.

The current status on wearable chemo-sensors is that functioning systems are still largely based on conventional electronic modules. Sensors and other components are increasingly being integrated into fabrics. Signal/comms/power lines are woven into the material using a wide variety of materials such as metallic threads, conducting polymers, and fiber optic cable. But there is a need for fundamental breakthroughs in the ways to do on-body sensing, interconnects, power, communications, liquid handling, etc. Plastic electronic and optical devices will play a huge role in the development of next-generation sensing platforms, Diamond said.

Dublin’s biomimetic low-power soft pump for low power control of fluid movement in channels and on surfaces is possible using electrochemically switched actuators

Radiant Sensing Technology to be Integrated into Textile Substrates Enzo Scilingo, University of Pisa, Pisa, Italy

Pisa University has developed an ultrasound (US) based transducer, and UWB radar. The US system is able to acquire cardiac low frequency signals as well as perform ultrasonic investigation providing helpful information on the cardiac status. Its crucial aspect is the good electric coupling skin-transducer or skin-electrode interfaces. The UWB system is based on recent advances in silicon CMOS technology that has allowed the realization of miniaturized, low-cost and low-power integrated system-on-a-chip sensors. A detailed study of the UWB radar on silicon technology (CMOS 90nm) has been carried out by means of both theoretical analysis and CAD tool simulations.


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Flexible Electronics & Displays Conference February 2-5, Phoenix, Arizona

In this first report from this FlexTech Alliance event, Phillip Hill covers presentations from DisplaySearch, Nerac, HelioVolt, Universal Display Corporation, GSI Technologies, Philips, and PVI

Flexible Displays Enter the Mainstream Jennifer Colegrove, DisplaySearch, Austin, Texas

2009 will be a special year for flexible displays. Flexible active matrix displays will be in the market, and likely from Polymer Vision, Plastic Logic, and PVI. Before 2009, all flexible displays were passive matrix or segmented. Flexible displays are complicated with many variable components. There are about 10 different display technologies that could be made into flexible displays, and about 200 companies are working on flexible displays. DisplaySearch forecasts that flexible display revenue will increase from $85 million in 2008 to $8.2 billion in 2018, for a CAGR of 58%. There were 23 million flexible displays in 2008; this will grow to 1.5 billion units in 2018. Electrophoretic and electrochromic will lead the shipment due to display card and smart label (e-label) applications. Plastic substrate was the dominant material for flexible displays in 2008. DisplaySearch forecasts it will still be the major substrate material by 2018. Typically every display has two substrates. Metal foil substrate flexible displays will reach the market with small volume in 2H 2009, but it still needs a plastic substrate for the front-plane.

Requirements for plastic as the front plane or as the TFT backplane Source: DuPont Teijin Film


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New and Overlooked Markets for Printed Electronics Kevin M. Closson, Nerac, Tolland, Connecticut

Closson listed and defined the markets, provided examples of each type, explained how the markets overlap, and identified the best three near-term opportunities. For these three, he addressed current market drivers and went into a case study: milk packaging. Printed electronics is attractive because it creates markets rather than competes in existing ones – both niche and mass markets. Often electronics is a small part of product cost. Closson discussed the best near-term opportunities for three areas: authentication, sensors, and medical. The market drivers for authentication are low cost; product volume varies by application; various substrates; often passive; ideally, does not require new infrastructure; but there are intellectual property issues. Drivers for medical are regulatory and privacy issues; an aging population (large market); and batteries as an enabler. Sensors open new markets – formerly “unmonitorable” become “monitorable”; enabling technology is the array of materials and substrates. Cost may or may not be a large issue, depending on the application, but there are privacy issues.

Rapid Low-Cost Printing of Building-Integrated High-Efficiency Thin Film CIGS Photovoltaics Louay Eldada, HelioVolt, Austin, Texas

The company’s technology is rapid low-cost printing of high-efficiency CIGS photovoltaic integrated circuits (PVIC). It completed $101M private equity financing Round B and has a prototype development facility of 38,460 square foot, and a 122,400 square foot factory. Eldada explained why thin film PV. There is significantly reduced cost; low material usage (1% of material usage in crystalline Si PV); it is not affected by silicon supply shortage; there is potential for improving cost throughout the value chain; it has better aesthetics in terms of the appearance of tinted glass on sides of buildings, slate on roofs, semi-transparent panels for vision glass; efficient and high performing materials; and better energy output – kWh/kWp. He went on to discuss building integrated PV (BIPV). Power buildings will become a multi-trillion dollar market. BIPV is the fastest growing sector of PV. Building integration leverages available surface area, installation cost, and proximity to loads. There are revolutionary products through efficient, durable TF solar cells embedded into traditional building materials where conventional products are unsuitable and not cost effective.

The future building environment will use energy conservation, reduced building operating cost, and also look better

Authentication is a key overlap to other sectors


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White Phosphorescent OLEDs for Flexible Lighting Applications Ruiqing Ma, Universal Display Corporation, Ewing, New Jersey

Ma first compared the different lighting technologies. Incandescent bulbs have a pleasing color, but are highly energy-inefficient. Fluorescent lamps are efficient, but are mercury containing. LEDs are bright and efficient for high intensity, “point source” applications, but with difficult and costly thermal management issues. Phosphorescent OLEDs are energy efficient, environmentally friendly and economic in an exciting new form factor, Ma said. White OLEDs enabled by energy efficient phosphorescent OLED (PHOLED) technology, open up exciting new ways to use white lighting. It has the potential to transform the lighting industry: from heat to light; from bulbs to panels; from rigid to flexible.

Flexible white OLED

He described WOLED device architecture and material design for low voltage. Layer thicknesses are optimized for color balance and low voltage. The nature of the interfaces affects operating voltage, charge balance, and efficiency. Stacking order enables high recombination efficiency. Energy transfer from blue emitter to green emitter is a mechanism for green and red emission (see diagram).

Additive Metal Flexible Circuit Technologies Rick Mental, GSI Technologies, Burr Ridge, Illinois

Mental kicked off by saying that flexible circuit fabrication is the unglamorous side of printed electronics. Emerging organic electronic technologies will require a means of interconnection both internally and externally. There is a wide range of existing and emerging flexible circuit technologies able to support near and long-term industry needs. This presentation provides a high level view of the overall space with a focus on additive metal technologies.

He went into the types of flexible circuits created by etching, printing, plating, etc. and the economics involved. With etched copper/aluminum, the percentage of copper coverage has little affect on pricing for etched copper. There are few economies of scale; the etch waste stream requires significant investment in water reclamation. With semi-additive copper, the substrate must be pre-coated with a 100% coverage seed layer, and lower cost printed resist limits image resolution (line/space). Photoresist provides excellent resolution but adds significant cost, and the wet etch process adds cost. Laser ablation involves extremely high capital expenditure, and a high-speed process (up to 150 images/second). Economics are highly dependent on the capture and reclaiming of the ablated metal.


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With polymer thick film silver, there are unpredictable cost swings linked to the market price of silver; and reducing resistance requires thicker layers leading to increased cost. Print and electroplate copper, on the other hand, requires printing and plating capability or a partnership. It also requires a conductive seed layer; low cost carbon plates are slow; high cost silver plates are faster. Finally, the “MicroCat” electroless copper process requires printing and plating capability or partnership; a non-conductive low cost seed layer. High-speed printing and low temperature drying reduces cost, and there is a low plating line operating expense because there is no high current bus system. Also, the stable chemistry can be “hibernated” between plating runs. Additive metal platforms provide cost effective options to traditional subtractive technologies. Pure metal conductors provide excellent conductivity, stability and reliability. Additive and semi-additive technology platforms can support a broad range of applications with increased substrate options. There is increasing interest and support from material and equipment suppliers, Mental concluded.

Future Plans for Flexible Electronics Eliav Haskal, Philips, Eindhoven, The Netherlands

Flexible devices will target three main criteria: robustness/flexibility/light weight; body compatibility; and/or low cost. These criteria describe the applications: for large-area, low-weight (displays, solar); around-and-in-body (implantables, patches); highly-integrated (RFID, etc); and print-any-device-on-demand. All of these will need new technology development, equipment, and materials. The opportunities will drive these different technologies forward at different speeds, and all technologies will be present for some time. What was once flat and fragile will become rounded and robust – where it’s needed or cheaper. Textiles and body-compatible large-area foils will provide new applications in medical and lifestyle domains. In addition, robust implantable devices coated with biocompatible materials will be needed. If (sufficiently-performing) printed electronics can reduce the cost of devices to a target where the volume can be manufactured and sold with a profit, then this will revolutionize the industry of device fabrication. If the organic semiconductor TFT cost structure is indeed lower than inorganic TFTs, then the market revenue (and application possibilities) will be larger for OTFTs than iTFTs. This depends on materials costs and fabrication equipment development. Most of the technologies face a long term before reaching product revenues that are attractive to larger industry. Support for the common aspects of flexible, printed, organic and roll-to-roll-processed technologies is needed to enable businesses to grow, giving time for the market to develop. Philips predicts an explosion in R2R and in-line printed devices, starting with displays and solar cells, moving toward other electronic devices, focusing on body-compatible devices.

Competitive landscape analysis

E Ink based electrophoretic display material on a flexible a-Si TFT backplane Source Pulsium Innovation Pilot


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Gen II E-books with Flexible Displays Ian French, PVI, Brighton, England

The content of this talk covered what we want from e-books; Gen I e-books (glass-based); Gen II e-books (flexible); manufacturing by EPLaR; TFT characteristics and displays; EPLaR displays, large and small; and future Gen III e-books. E-books have to be less polluting than paper. In 2007 US newsprint consumed 95 million trees, generated 126 billion gallons of wastewater, and emitted 73 billion pounds of greenhouse gases. Paper and paperboard is the largest component of US municipal waste (32.7%). Paper is the UK’s 4th most polluting industry. Flexible electronic paper will make e-books thinner and lighter; reduce breakages and extend uses like e-schoolbooks and service manuals; make larger e-books and e-newspapers practical; and make reading e-books more enjoyable and natural, French said. What would be the perfect e-book, French asked in conclusion. It should be like paper for the eyes (most people find reading LCDs more tiring than reading printed paper). All books and periodicals should be instantly available everywhere. They should use displays that are thin, light, and robust, with pen input and touch input. They should also feature color and animations, and be foldable (or rollable). Not every e-book will have every feature because of cost. The best quality B/W for reading will probably not have color.

http://guest.cvent.com/EVENTS/Info/Agenda.aspx?e=60856a63-5f6b-44f0-addb-39e916f894d2

9.7-inch EPLaR display


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OLEDs World Summit November 10-12, 2008, La Jolla, California

In this third of three reports on this Intertech/PIRA conference, Phillip Hill covers presentations from Tokki Corporation, FUJIFILM Dimatix, Universal Display Corporation, Kodak, Novaled, Corning, Ignis

Innovation, and EMD Chemicals

OLED Mass Production System For Large Size Substrates Eiichi Matsumoto, Tokki Corporation, Tokyo, Japan

The presentation covered a mass-production system of OLEDs for G4/half-size substrates; vertical-type equipment for over G4 size substrates; and HotWall sources for lighting. The system for G4/half-size substrates is based on the concept of “parallel shot source” and is compatible in material yield and film thickness uniformity. The distance between source and substrate is shortened, and the number of sources is increased. The substrate is fixed, and source is moved. The organic material is not overheated by optimization of heat design of the evaporation source. Deposition rate is stabilized for a long time (144 hours). The deposition rate is always controlled. The effect is material yield is about 10-20%. Film thickness uniformity is <±5%, and rate stability is <±5%. The organic material has no degradation. Tokki has also developed vertical-type equipment because there is a problem with large substrate sizes because of bending of the substrate, and adhesion of the mask and substrate. Two sources of host and dopant move up and down. Rate stability is ±5%, and thickness uniformity is ±5%. An alignment system uses a CCD camera with an accuracy of ±5μm.

Inkjet Printing as a Manufacturing Method for Light Emitting Displays Chuck Griggs, FUJIFILM Dimatix, Santa Clara, California

The presentation covered a company overview; inkjet printing schemes; display equipment; piezo inkjet printheads; fluid considerations; and what is state-of-the-art? The fundamental fluid requirements for acceptable for inkjet performance involve viscosity – Newtonian; surface tension; evaporation rate; particles must stay suspended and not agglomerate – molecular shape; and must interact with the substrate in an acceptable manner. Non-wetting coating on the nozzle plate increases materials compatibility: there is an increased surface tension range – 8-35


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dynes/cm; there is increased solvent selection of organic and aqueous. Non-wetting coating increases uniform droplet formation (see photos). State-of-the-art inkjet printing is 1pL and below drop size printheads; ±5 micron 3-sigma directionality; “fly height” of 85 microns; Gen 10 single pass printing; 2048+ individual nozzle printheads; 33,000+ nozzle print head arrays; and flow through circulation in the print head for improved reliability.

Commercial-Ready Small AMOLED Using Amorphous Silicon TFT Backplane Corbin Church, Ignis Innovation, Montreal, Quebec

Church kicked off by comparing backplane technologies (see table). Temporal and/or spatial non-uniformities are the major drawbacks. Small mobility degrades the aperture ratio, spatial resolution, pixel gain, and settling time. Backplanes of a-Si:H offers higher capacity and scalability.

A high-resolution (180ppi), bottom emission panel with good aperture ratio (27%) is possible using a-Si. Amorphous silicon TFTs have been proven to exhibit commercial level reliability using a novel pixel circuit and other design tricks. Power consumption is 45% lower than LCD, and comparable to polysilicon, especially when the OLED is located in the drain of the drive TFT. Bottom emission (250ppi) and top emission (300ppi) are possible using the new Ignis HR pixel architecture. Cost structure, scalability and capacity of an a-Si AMOLED will make it significantly more competitive to LCD.

PHOLED Technology and Materials: The Energy Efficient, Environmentally Friendly and Cost-Effective Solution for High-Performance Displays and Lighting Janice K. Mahon, Universal Display Corporation, Ewing, New Jersey

The company’s business model is technology licensing, PHOLED materials supply, and technology development and transfer services. It has over 850 issued and pending patents worldwide. Fundamental PHOLED patents have now been issued in the US, Europe, Japan, Korea, China, India and Taiwan. Materials are produced by PPG


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Industries, and device-qualified and sold by UDC. They have been in commercial use since 2003. The company offers a range of customized services supporting the smooth adoption of its technologies and materials by its manufacturing partners. The company says LCDs are the competition so it has collaborations to expand OLED material infrastructure and manufacture materials compatible with UDC PHOLED materials: Nippon Steel Chemical Co., Mitsubishi Chemical, Idemitsu Kosan Co., and LG Chem. They also evaluate many other third-party materials for use with their PHOLED technology. According to market research by the OLED Association, for mobile computing each person thought that power consumption was an issue, especially for devices that access the Internet or do e-mail, because Internet pages have so much white space. Power consumption in video applications on OLEDs is 25% to 50% of comparable LCD power consumption, but peak power consumption on an OLED, e.g. a full white screen, is 2x to 3x the power of a similar size LCD at the same luminance. Peak power is a concern as there is a need to design for peak power. They felt that OLEDs had to be less that 2x peak power to be interesting. UDC says that phosphorescent OLEDs are the solution because they use four out of four spin states instead of one with other OLEDs.

Mahon showed a quirky world map scaled to energy consumption by country. The whole of Africa is the tiny inverted “L” shape in the middle. Energy efficient lighting is critical for world health, UDC says.

Advances Towards Realizing Production of Large-Size OLED TVs John W. Hamer, Kodak, Rochester, New York

The presentation covered OLED TV displays; advances in OLED materials and formulations for large displays; advances in production technology; and remaining challenges. Hamer covered the state of manufacturing. All AMOLED products use LTPS TFT and RGB-patterned OLEDs. All AMOLED products have the OLED vapor deposited onto ½ glass of size Gen 4 (or smaller). The industry will not become significantly profitable until Gen 5 or larger is achieved. To manufacture at Gen 5+ will need scalable low-cost backplane: LTPS, a-Si, MOx, oTFT; and scalable OLED deposition: vapor, solution, transfer. Hamer described advances in production technology: Kodak’s vapor injection source technology (VIST) (see photo); unlit-dot reduction technology; and global Mura compensation. Kodak’s VIST coupled to a Gen 5 linear manifold


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The remaining challenges are:

Backplane technology: needs to have the cost, scalability, and uniformity of a-Si, and needs to have the stability of LTPS.

OLED lifetime: current white OLED materials and formulations can meet TV lifetime requirements. There is a need for more understanding of image-stick requirements.

Top-emission technology: need for higher conductivity transparent electrode materials and processes; or need bussing/strapping technology on top of electrode; or need low-cost method for forming vias from top electrode to the busses in the backplane.

Hamer concluded with the recently announced Kodak OLED Wireless Frame. It is an RGB patterned, active-matrix LTPS, bottom emitter, with 16:9 aspect ratio, 800x480 pixels, 7.6-inch diagonal, and 30,000:1 contrast (see photo).

The Future of OLED: It’s All Up to the Yield! Gildas Sorin, Novaled, Dresden, Germany

Part of the presentation covered lighting. OLED laboratory efficiencies are much closer to product efficiency than for any other product. Where is the competitive edge for OLED compared to other products, Sorin asked. The DOE CALiPER program has investigated several SSL lamps. Often strong deviations were found from laboratory to real life efficiency. The vast majority of lamps are below 40lm/W efficiency. Current lighting solutions require regular maintenance cycles. No “mount-and-forget” solution is available on the market yet (see photo of a conventional solution). For OLEDs, is a certain defect level acceptable, Sorin asked. Yield improvement comes through defect tolerant structures. Novaled has developed special failure tolerant electrode structures for large area OLEDs. The photograph shows 9 shorts on one 15x15cm² demonstrator – the device is still fully operational. The electrode structure is protected by Novaled IP.

The left image shows conventional fluorescent lighting at Munich airport. The right image shows nine defects but the device still works


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Sealing and Backplane Solutions for OLEDs John E. LaSala, Corning Incorporated, Corning, New York

Corning forecasts that AMOLED will likely be a high-end niche display technology in mobile phones in the next few years. The AMOLED value proposition resonates with today’s demands of high-functionality portable devices, and offers multiple opportunities for Corning innovations, such as its Jade polysilicon substrate and its Vita OLED frit sealing. There are two challenges to OLED success: longevity and backplane performance. OLEDs are very sensitive to air and moisture. The industry needs a robust hermetic sealing solution for OLED. Corning’s glass-based approach offers an impermeable seal, increasing the lifespan of OLEDs by locking out air and moisture. And OLEDs require a backplane with much higher performance than a conventional LCD. Corning has created a winning sealing solution for OLEDs and is working with all key OLED manufacturers. Corning’s Vita solution enables a hermetically sealed OLED device – the only fully hermetic solution commercially available. Jade meets LTPS compaction/variability level requirements without any secondary heat treatment. Jade has a compaction variability advantage “built in” because of its high viscosity. It is likely to reduce loss due to compaction variability. Jade provides smaller sag/deformation change in customer processes, and provides flexibility to raise process temperature for innovation. It supports down to the 1.5μm design rule. Jade’s compositional modifiers enable cutting with a lower wheel load, and enables a more consistent, wider process window for cutting with a significant mean strength advantage over standard a-Si glass. Panels are less susceptible to breakage due to fatigue. Jade has higher edge strength with better consistency than a-Si glass, and there is less breakage due to handling in process.

Small Molecules versus Polymers: Why Doing Both Makes Sense! Dieter Schroth, EMD Chemicals, Darmstadt, Germany

EMD Chemicals is part of Merck. Its developments are based on two basic platform technologies: vapor based materials (small molecules); and solution based materials (polymers, soluble small molecules). It is the only company offering products from both material platforms. The OLED market will continue to grow strongly but will not challenge LCD in the foreseeable future, Schroth said. The key for growth is in large area applications. The enabler for large area is solution processable OLED materials. Cross fertilization across the whole value chain between small molecules and polymer technology yields results, he said, based on lessons learnt with both technologies.

Multiple opportunities for Corning in a mobile device


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Plastic Electronics Conference and Showcase October 28-29, 2008, Berlin, Germany

In this second report, Phillip Hill covers this conference organized by the Plastic Electronics Foundation and Intertech/PIRA with presentations from Georgia Institute of Technology, University

of Western Sydney, Institut de Ciencia de Materials de Barcelona, Heliatek, Acuity Brands Lighting, Cambridge University, and Solarcoating Machinery

Optimizing Organic Multi-layer Photovoltaic Cells Bernard Kippelen, Georgia Institute of Technology, Atlanta, Georgia

The roadmap for OPV technologies is to increase efficiency, demonstrate scalability and streamlined manufacturing, develop low-cost packaging technology, and demonstrate long lifetime and stability towards a price of <$1/Wp. The presentation covered organic solar cells with large excitonic diffusion lengths: pentacene/C60 solar cells; modeling OPVs using the equivalent circuit model: origin of VOC; and packaging and area scaling of multi-layer molecular organic solar cells.

Oxygen and water degrade the performance of most organic solar cells currently being studied. Encapsulation is needed to protect cells from the ambient atmosphere. 200nm of Al2O3 deposited by atomic layer deposition (ALD) is one encapsulation that can extend device lifetime in ambient atmosphere.

Kippelen concluded by saying that large exciton diffusion lengths (>70nm) are found in pentacene by modeling of EQE in multi-layer solar cells based on geometry and optical constants. The excitonic bottleneck has the potential to be overcome in multi-layer organic solar cells. Reverse saturation current found to be thermally activated with a certain barrier height correlating with the difference between HOMO and LUMO gap. An analytical expression for the open-circuit voltage has been proposed. Georgia Tech has developed packaging technologies for OPV. Initial tests yield up to 10,000 hrs of shelf lifetimes. They have also demonstrated electrode technology for OPV: maintained fill factor for areas of single cells of up to 80cm2.

Light Way: Revealing the Next Step in Ultra Efficient Lighting for Today and Tomorrow Damian Savio, University of Western Sydney, Longueville, Australia

The motivation for this research stems from the fact that currently, lighting remote indigenous communities of Australia is one of the most problematic areas that needs to be addressed. At present there are around 40% of indigenous homes that do not have safe electrical lighting or proper working light fittings. The solution is to turn night into day by storing the sun’s energy during the day, which can power louvers at night.


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Mobile battery pack allows the light to be taken anywhere. Each louver produces the same amount of light as a 60-watt incandescent globe with just 5 watts. There are other possibilities such as colors and customization

(see photo). Applications could be in high-rise apartment buildings, museums, department stores, homes, supermarkets, and office blocks.

From Conducting Charge Transfer Salts to Flexible All-Organic Strain Gauges Elena Laukhina, Institut de Ciencia de Materials de Barcelona, Barcelona, Spain

The motivation for this research is that advanced biomedical technologies will provide medical staff with miniature sensors capable of measuring the delicate human tissue movement that relate with numerous physiological processes occurring in a human body. Because of this interest, design and manufacture of small strain gauges capable of detecting extremely fine mechanical or pressure variations as electrical signals is a significant contemporary challenge. Flexibility and processability are often cited in this regard. The main goal was a search for advanced flexible synthetic materials with conducting properties that could be very sensitive to delicate pressure changes. Are there stable, flexible, conductive all-organic materials that are cheap? Yes, say the researchers: there are polymeric films on the topmost layer of a TTF-based organic conductor. They have developed a conducting all-organic “BL-film”. BL-films with a layer of a TTF-based molecular conductor are highly sensitive all-organic strain gauges. BL-films with strong temperature dependence can be used in fine temperature sensing. BL-films are cheap materials and have a good long-term stability.

The advantages of BL-films are intimate contact between the layers with no adhesive problems; a simple synthetic procedure; good long-term stability; the electronic circuits may be directly designed on the conductor layer; they are light, transparent, flexible and cheap; the electronic circuits can be of a nano-, micro-, or macro-scale size, and they may also be configured in different ways; and the polymeric matrix can be prepared from different commercial polymers that vary in their mechanical, optical and chemical characteristics.

Vacuum Deposited Organic Solar Cells for Future Mass Production Martin Pfeiffer, Heliatek, Dresden, Germany

The presentation covered an introduction to the company; efficient organic p-i-n type tandem cells; oligothiophene based absorber materials; lifetime and thermal stability; and modules with integrated series interconnection and upscaling issues. Heliatek was founded in July 2006 and is a joint spin-off of IAPP, University of Technology,

The prototype of a device that employs BL-film as a gauge for breath control


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Dresden, and the University of Ulm. It had seed financing of €600,000 from the HTGF ministry and a business angel (H. Eggers). A second round of financing (€4 million) closed in June 2007 with investors including BASF and Robert Bosch GmbH. Its vision is to overcome the <€1/Wp barrier. Its mission is to develop a mature technology of organic vacuum-deposited solar cells, and establish a mass-production line. The OLED industry needs to compete with LCD Gen 6 and 7 (>2x2m2), and is working on OLED lighting/ It is about to develop large-scale in-line production tools. Organic solar cells will profit from such tools, and Heliatek thinks it will have a long-term stable 8% efficient organic solar cell available by 2011.

Enabling OLEDs for Future of OLED Lighting Peter Ngai, Acuity Brands Lighting, Berkeley, California

Peter Ngai gave a mainly visual presentation on the benefits of OLED lighting, some of which are shown below. While OLED for lighting is still in its infancy, Acuity Brands Lighting believes that early dialog between the OLED industry and its intended client, the lighting industry, is paramount. Ngai pointed out that there was a difference between “need” and “want”. “Need” is the threshold below which OLEDs for general lighting will not be considered as a realistic approach. “Want” is when OLEDs for general lighting is considered as at par with existing approaches. With color temperatures (white light) and consistency through life, we need 3500K, and want 3000K, 3500K, 4000K and 5000+K. For color rendition, we need 80+ CRI, and want 90+ CRI. For color tuning (color changing), we need dimming capability, and want color tuning. On physical characteristics, transparency is nice to have but not a must, size is flexible, thinness is not much of an issue, and physical flexibility is nice to have but not a must.

On the left, due to the nature of OLED and its characteristics, it will compel architects and designers to rethink their approaches to lighting designs. On the right, the aesthetic and emotional effects offered by the potential richness of

colors and color dynamics will lead to opportunities of combining OLEDs and LEDs for general lighting and localized or focused lighting


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Ngai said that OLEDs are expected to not only transform but indeed reinvent lighting; OLEDs offer designers a new lighting design platform which allows the integrations of the lighting and architecture that is not possible currently

Integration of lighting into ceilings and walls

Electronics with Organic Semiconductors Richard Friend, Cambridge University, Cambridge, England

Sir Richard discussed the use of organic semiconductors in LEDS, solar cells, and transistors. Have performance limits been reached, he asked: efficiency (LEDs, PVs), speed (FETs), manufacturability, and durability. He discussed the issue of molecules or polymers. Single crystals of molecular semiconductors are fragile, but vacuum-sublimed thin films with non-crystalline structures can give uniform and stable structures. Stacked structures and demonstration of clean heterojunctions came with a breakthrough by Ching Tang of Kodak in 1987. Solution processing of polymers gives excellent film-forming properties. Disorder is inherent, which limits semiconductor mobilities. Multi-layer structures are hard to make (orthogonal solvents or cross-linking chemistry are needed). Novel architectures – distributed heterojunction – are good for solar cells. Sir Richard turned to recent work at Cambridge on metal oxide charge transport layers in polymer LEDs. Thin-film and nanostructured metal oxides have been much studied for photovoltaic diodes. ZnO and TiO2 provide wide band gap and high refractive index.


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Deposition is via sol-gel, spray coating, etc., plus thermolysis. LEDs have been produced with efficiencies above 2cd/A, and much reduced need for encapsulation. In summary, Sir Richard said that OLED efficiency is remarkably high – good enough for lighting. Solar cell efficiency is not good enough yet – it may need new architectures to achieve this. With transistors, mobility of charge carriers is adequate for certain applications (comparable to amorphous silicon). Higher mobilities (>10cm2/Vs) will enable new applications.

Production Technologies for Flexible OPV: Challenges 2008 Thomas Kolbusch, Solarcoating Machinery, Dormagen, Germany

The company’s vision is to become the machinery solution provider for flexible solar, revolutionize the equipment manufacturers’ market approach, and provide the equipment solutions for the world’s renewable energy needs today. Its business idea is the development and integration of equipment for flexible solar cell technologies; encapsulation-packaging of solar cells; automation of processes for PV modules; and flexible photovoltaic-to-substrate bonding technologies. In conclusion, Kolbusch said that 2GW in 2010 for flex solar could be real. No efficiency records are needed, but scalable process for reproducible results are. Equipment solutions makers and R&D people have to cooperate closely. For BIPV, lifetime will turn out to be more important than efficiency. There is an urgent need for barrier materials at reasonable costs.

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The MultiView compilation newsletters bring together the contributions of various regular contributors to the Veritas et Visus newsletters to provide a compendium of insights and

observations from specific experts in the display industry. http://www.veritasetvisus.com

Production facility in Los Angeles manufacturing solar cells by R2R


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Silicon Valley Photovoltaics Society (SVPVS) Networking, to advance (flexible) solar technologies

by Jurgen Daniel

Jurgen Daniel is senior scientist at the Palo Alto Research Center and founder of the Silicon Valley Photovoltaics Society (SVPVS). Jurgen received a degree in physics from the University of Erlangen-Nuremberg, Germany, and a Ph.D. degree in electrical engineering from the University of Cambridge, UK. Amongst other areas, his research has focused, on micro-electro-mechanical systems (MEMS), displays, flexible printed electronics and recently, photovoltaics.

There has been tremendous growth of the solar industry over the past years, but the overall contribution to the world-wide energy supply still remains small. Plenty of room for further growth remains, particularly in areas such as California which has a goal of getting 33 percent of its electricity from renewable sources by 2020. Several technologies, but also government regulations and private investment will contribute to this development.

Solar energy and in particular photovoltaics (PV) is essential for a well-balanced energy mix and it includes many aspects such as materials resources, cell manufacturing, module assembly, installation and various schemes of solar financing. Considering only solar cell technology, there is a wide range of options with conventional crystalline silicon or III-V semiconductors but also thin-film materials such as amorphous silicon, cadmium telluride (CdTe), copper-indium-gallium diselenide (CIGS), or dye sensitized cells and emerging organic PV materials. Some of these photovoltaic technologies are based on flexible substrates which enable module flexibility, improved robustness, light weight and potentially cheaper manufacturability. Amongst the companies working on flexible PV are United Solar Ovonic, PowerFilm, Global Solar, Ascent Solar, G24 Innovations, Nanosolar, MiaSolé, SoloPower and Konarka.

Silicon Valley is well represented in this area with a host of PV companies (including flexible PV), important research activities and substantial public interest in Green Technology. Moreover, many companies from other sectors are trying to enter PV and a significant number of people from other industries have moved into the solar industy or are trying to. Considering this transformation, it is important for companies or individuals to be well aware of existing or emerging technologies and trends and also to benefit from forming strong networks with others.

Almost one year ago, the Silicon Valley Photovoltaics Society (SVPVS) was founded in order to further advance Solar Technologies in Silicon Valley (www.svpvs.org). The charter of SVPVS is to create a forum for entrepreneurs, business people, investors, engineers and scientists who are active or interested in photovoltaics or related technologies. With a strong society, we seek to promote the competitiveness of the PV industry in the San Francisco Bay Area by improving the awareness of relevant technologies, by forming a network between business and science and by simply getting to know each other in this field. The society has a monthly meeting (so far, the meetings have been held at the Palo Alto Research Center) with an invited seminar and abundant networking opportunity. No registration is required to attend the meetings and the seminars are free of charge. Currently, the ‘membership’ consists of joining the monthly email notification list ([email protected]). However, the network is not limited to the Bay Area since there is also an SVPVS LinkedIn group which allows people from other regions to connect and to discuss relevant topics (so far over 500 people have joined).


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Past SVPVS seminars have covered a wide range of topics, ranging from the role of venture capital in the solar industry and the solar leadership of utilities to more technical talks about thin-film CIGS or CdTe. Amongst the speakers were Eric Wesoff (Greentech Media), Rommel Noufi (SoloPower), Chuck Hornbrook (PG&E), John Benner and Tim Gessert (NREL). A complete list of past presentation as well as some of the slides is available on the SVPVS website.

The response of the audience to the events has been very good and the broad mix of topics has been welcomed. And regarding the society’s symbol, it is a sun with the outline of the San Francisco Bay area (not a printer malfunction as some have been guessing). Suggestions for future speakers, particularly also in the area of flexible photovoltaics are always welcome and can be sent to [email protected].

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Cost reduction advances for manufacturing flexible displays and electronics

by Abbie Gregg

Abbie Gregg has spent the last twenty years as an engineering consultant, specializing in microelectronics process analysis and startup / restructuring of laboratories and manufacturing facilities. Abbie Gregg, Inc. (AGI) is her consulting firm, specializing in programming and design of cleanrooms and advanced technology laboratories. Layout, Room Conditions, Utility Matrix, and Specialty Systems design have been provided for Industrial and University Clients. Her previous experience is in process engineering, operations management, and technical strategic planning for major semiconductor device manufacturers. Her areas of specialization include Integrated Circuits, Flat Panel Displays, TVS Devices, and Multichip Modules. Consulting projects have included yield enhancement, improved operations effectiveness, systems and programs for computer aided layout and design of Cleanrooms. Abbie’s team also developed software models for semiconductor and FPD product cost, outsourcing analysis, cost of ownership and factory modeling. Abbie holds a Bachelor of Science in Metallurgy and Material Science from the Massachusetts Institute of Technology, and studied Electrical Engineering at the University of Maine.

Recently, AGI has found our clients are interested in a better understanding of costs of the widely diverging technologies using flexible microelectronics manufacturing techniques. These needs can be broken down into 4 areas:

• What are the Current Cost Drivers in Flexible Displays and Electronics? • What are the Key Equipment Advances in Process and Automation that can help reduce costs? • How does the scale of Operations and Geographic location affect cost? • Where are the best Future Opportunities for Cost Reduction?

AGI has recently reviewed the key cost drivers in Flex Displays and Electronics using our cost models for a variety of clients and products. Some of the recent applications we have studied include manufacturing of test strips for diabetes, and comparing two techniques: printed with ink OR laser-ablated metal. We have also compared photovoltaic devices: CIGS and organic materials. In touch screens we modeled waveguide based touch screens and PC board type that uses a pen and includes a digitizer as well as touch. In displays we have looked at TFT displays as well as simple dye photo-chromic displays and LED displays on flex for credit card applications. We also analyzed manufacturing for batteries in a cosmetic patch or RFID product looking at an ink-based manufacturing approach. Two areas emerged as key cost drivers:

• Materials • Product packing density

We find that Materials for flexible electronics continue to be expensive, although inexpensive materials in roll format are one of the dreams of flexible electronics, so the high cost of silicon and glass can be eliminated. Organics are now popular because electronically/optically active materials and substrates have been developed in research. Many have inexpensive base formulas which should eventually lead to low cost process materials. However, most electrically or optically active materials are still moisture susceptible, and have a relatively short shelf life before a baking or curing step. Organic materials also suffer from a lack of precision in chemical formulations causing waste, and unpredictable yield, although testing and mixing are becoming more rigorous. Improvements in chemical formulation consistency will be very important in yielding lower costs and economies of scale.


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The second big problem with materials causing waste and high cost, continues to be lack of precision in physical dimensions and retention of dimensions of substrates during processing, causing misalignment of multiple layer patterns and lack of tolerance in these patterns, ultimately leading to scrap.

One big recent advance is, finally, a “display ready” planarized PEN substrate from DuPont Teijin Films. Teonex PEN films are a high performance extension to the existing range of Melinex and Mylar polyester film products and bridges the gap between price and performance for polyester and other films.

Metal foils are also enjoying wider use due to improvement in surfaces, and reduction in defects. A recent announcement from Lehigh is one of several pointing to improvement in the analysis and implementation of metal foils for a variety of photovoltaic and display applications.

Lehigh University’s Display Research Laboratory, which will investigate the suitability of a number of different metal foils for use in the manufacture of flexible display backplanes. The $270,000 cost-shared award will be the first-ever systematic study of metal foils with the goal of yielding alternative substrates to today’s commonly used stainless steel.

Specifically, Lehigh University will work cooperatively with Hamilton Precision Metals (HPM), a business unit of the Specialty Metal Products Division of AMETEK, Inc. to identify promising material candidates with parameters for improving yields on metal backplanes for flexible displays. Important factors in creating displays include good thermal coefficient matching and smooth substrate surfaces for minimal display defects, both of which are current issues with using stainless steel as a substrate. In addition, this study will assess the costs associated with each foil in a high-volume manufacturing environment – enabling selection of more cost-effective approaches to producing displays. The year-long project will be led by Dr. Miltiadis Hatalis, professor of electrical engineering and computer science at Lehigh.

Dr. Mark Robinson, vice president of technology at Hamilton Precision Metals, noted, that the metal foils being characterized by Lehigh will have all been prepared by the same cold rolling process, using the same equipment.”

Once the film characterization has been completed and the most promising materials identified, additional samples of the selected foils will be made available to the US Army-sponsored Flexible Display Center (FDC) at Arizona State University to further test its capabilities.

Product packing density is the second area with a large impact on product cost. The basic rule of product packing density is that high device packing density is needed to achieve low cost. However, as many clients come to us with overly aggressive packing density as come with far too loose packing density. Those with overly aggressive packing density lose out on yield. Those with tool loose packing density lose out on throughput. The role of product engineering in accounting for and carefully analyzing the following parameters is critical:

A – Alignment tolerances of multilayer devices B – Processing tolerances of line-width

Design rules for new flex devices in all applications are still evolving and vary by type of material and equipment. For example, a waveguide made of a thick proprietary polymer will not have the same line width tolerances when exposed on a Tamarack aligner with broad spectrum UV light as does a classic UV sensitive photo-resist. Mechanical,


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electrical, and process engineers must work together and create test patterns and metrics for new device types. It is very important to characterize the limits of any pattern and overlay tolerances in order to provide better design guidelines for the next generation of devices one plans to produce. As an example, on large area Photovoltaic devices on flex, maximizing area open to sunlight is critical in device layout. This open to sunlight area is the biggest cost driver!

PV Design Rules Impact is shown in the table below where the variation in fill factor between 75% and 95% of this device changes the cost per watt from $35.78 to $30.85 for the same cell efficiency, volume and substrate cost.

Here are some other examples of Flexible Electronics devices where materials were the major cost drivers.

This flexible medical device fabricated using a Metal Sputter/ Laser Ablation Process had 91% of its costs attributable to the materials. The precious metal ablation and recovery was not only the largest cost by far, but also would fluctuate with market price of this precious metal, although the product price to the customer could not vary accordingly, it was highly regulated.

In this PV device the materials including the substrate make up 48% of the cost.


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Another typical flexible electronics cost model for a semi automated line showed the percent of costs due to materials increased as volume went up because while the labor and equipment efficiency increased with volume, the absolute value of material costs per unit remained the same.


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Process Automation- Advances in Handling Flexible Substrates: AGI has also noted some recent advances in Process and Automation. Webs are now routinely being customized for varying products and midprocess techniques, and webs are being slit to provide the right width for various sections of the process. Wide areas are still being used for web based screen printing

Narrow webs are very high speed for laser ablation. 6 inch to 12 inch is the most common size web for processes under development. We have also seen some automation of ‘temporary” processes using rigid “carrier” techniques, including release of flexible substrate devices when completed, from glass or wafers.

Automation of flexible sheet processes using modified rigid substrate techniques has been successful this year with modified robotics, chucks and edge gripping devices as well as slides being used to handle flexible substrates up to 500 x 500 mm. The common themes for successful flex substrate processing automation have been:

High quality motion control Optical inspection, with feedback for web alignment and

control Precision drum fabrication Temperature control of drums and suspended webs. Mini or microenvironments for cleanliness

Another piece of good news is that formerly “in house” expertise is now available to assist companies without roll to roll or flex handling experience in developing automation for new flexible device manufacturing. Standard flex handling automation products are not totally there yet, but are developing.

Sheldahl spin off – Northfield Automation Unisolar- Ovonic spin off – ECD

SSEC, NexTech FAS, RPO and Tamarack collaborated on flex sheet handling for a variety of photolithography like processes. Polaroid, Konarka's new PV on Flex plant in New Bedford, Mass., formerly owned by Polaroid Corp., has converted Polaroid's printing systems to deposit organic materials. The equipment prints the semiconductors onto flexible backings. This type of equipment advance will generally move the state of the art forward for Flex substrate handling in roll to roll format.

These advances by equipment suppliers, equipment integrators and foundries will allow those with specialized device needs to shop around for either experts to assist them in developing flexible substrate handling suitable for their process and device, or perhaps, to outsource the processing to a foundry where existing machinery can be customized for that material and device application.

Robotic Handling of Flexible Substrates: The large scale of flexible electronics operations were supposed to help with cost reduction, and

Flex Handling Techniques: Edge Grip and End Effector for High Precision

Positioning

Robotic Handling of Flexible Substrates into round chamber for processing.

Flex Substrate Edge and Pin Handling with End Effector – High Precision


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push us to roll to roll processing from sheets. AGI’s recent work and cost models of roll to roll scale ups show that volume plays an important part in reaching the required cost point, and that geography continues to play a part in the location of flexible electronics manufacturing. Our findings include the following:

1. Roll to roll scale ups require volume over 5 million per month for small devices, 1 million per month for large

2. Flex on large sheets (500 x 500 or so) requires demand of 0.3 to 1 million per month for small devices. 3. Most complex device makers seek Asian partners, especially if automation and inspection are

incomplete. Taiwan and China are most willing and able due to their low labor costs; experience in inspection and testing of microelectronics devices and their experience in front end fabrication techniques such as clean coating, careful heat treating, photolithography, patterning, and custom chemistry formulation.

4. PV manufacturing can afford to automate to medium size webs (10 to 24 inch) in US, Europe with some investment and incentives. This is due to high volume needs, low product diversity, less device cleanliness requirements, and less critical patterning compared to other Flexible electronics.

We have seen the trend to partner across the globe for risk reduction. For new technology, pilot operations often start in the Home country near an R&D center. Usually these start with a small flex substrate or narrow web. The move to a larger web, larger sheets or the sheet to web transition requires an automation partner with flex substrate handling, control and mid-process experience. This move also usually requires Capital investment or a manufacturing partner with a similar process line. Such manufacturing partners are rare due to the wide variety of different materials being used, and associated fears of cross contamination. The first step for scale up is often a 1 up tool set with automation. This can work for high product demand with a low product mix (not many different products), such as PV.

One of our flexible battery clients moved first to automation, then found their diversity of products and the need to allow more device variety made the scale of their roll to roll automation too large. They went back to a sheet based process for some products, and moved those operations to China to gain efficiency in the sheet format. The medium size sheet format and quick turnaround of device tooling allowed them to optimize the volume of each product run, maintaining the product form factor variety that their industry demanded. Large volume devices are still built on the roll to roll line.

Future Opportunities for Cost Reduction address materials, product form factors, and automation opportunities discussed above. The industry needs scale up and better control of specialty liquid materials used to create the device portions of flexible electronics and electro optics. The ability to use slurries and coating and casting techniques for electronic materials is a critical ingredient in low cost processing. The industry should bring improved liquid formulation techniques of bio/pharm to electronics. Previously electronics was mostly a solid state technology, relying on gases and solid materials, except for liquids that were eventually removed from the device such as photoresists and etchants. Additionally, the industry should expand their use of extrusion coating and other methods for dispense volume control, since electronic materials will continue to be one of the most costly elements of production. The continued cost reduction of substrates, which are growing in variety, but are still a large cost contributor is also critical. The industry must continue to advance the use of common substrates, with common properties like surface quality and edge control. This will lead to higher volume, which will help attract interest from the supplier community to meet those needs of the flexible electronics industry. For those devices that are high precision, they will continue to be constructed on carrier substrates to achieve dimensional control. Therefore, there needs to be continuing work on better attach and release mechanisms and materials.

In the product design arena, many improvements can be made to achieve cost reduction. The industry must become conscious of design rules for flexible electronics, which do vary depending on device type and equipment used in the process. There needs to be an effort by each company to understand and improve their own device design rules


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to make more efficient device layouts. Along with this work, some effort to minimize Product mix, or create a family of devices using similar layouts might allow larger runs, making for more efficiency and lower costs.

The industry also needs improved testing and inspection for less waste. In roll to roll processing, many defective devices can be processed after it has become obvious that they will not yield, due to their position at mid roll.

We expect to see gradual progress in automation. First we will see manufacturers automate individual tools or process steps for flexible substrate processing. Next, we will see “islands of automation” where common handling requirements, throughput and form factor make a common substrate handling mechanism useful. Finally manufacturers will link these “islands” together in a full line with common substrate format, but perhaps different handling techniques, and they will be adjusted for throughput by balancing the slow and fast process stations. This may occur in roll or sheet format, and we believe that “Islands of automation” in roll format are becoming popular already.

http://www.veritasetvisus.com


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ITO Market Opportunities Liner Notes from NanoMarkets' Webinar on ITO Market Opportunities

by Lawrence Gasman

Lawrence Gasman is principal analyst and founder of NanoMarkets LC, in Glen Allen, Virginia. He has over 25 years of experience as a high-tech consultant for companies including Analog Devices, Cisco, Hewlett-Packard, IBM, Intel, Fujitsu, NEC, Nortel and NTT, and is also the author of three books on telecommunications topics. He is also on the editorial board of the Foresight Nanotech Institute and is a regular speaker at various nanotechnology and display related conferences. The following is a write up from NanoMarkets' Webinar hosted on June 16th, 2009. http://www.nanomarkets.net

The size of the ITO market is such that even small inroads into this market by ITO alternatives could lead to substantial revenue opportunities, according to a Webinar

presented this week by NanoMarkets, LC, an industry analyst firm based here. In this webinar, NanoMarkets discussed the performance of ITO and its alternatives, emerging applications with potential opportunity for non-ITO transparent conductors, as well as market expectations for these materials over the next eight years.

More about the Webinar: ITO has long been the material that manufacturers of flat-panel displays love to hate. ITO is not very conductive, and as a transparent layer, it's not very transparent. Once applied, it's brittle and therefore not conducive to applications that involve flexing. And finally, the price of this mediocre performance is quite high, because ITO is dependent on indium, which typically garners a high price.

All of this would seem to suggest an environment ripe for alternative materials that boast improved performance. As NanoMarkets warned in its 2008 report, The Future of ITO: Transparent Conductor and ITO Replacement Markets, however, alternatives will make progress but will do so slowly. NanoMarkets' analysis suggests that even by 2016, ITO will still have about 90 percent of the high-end transparent conductor market. That being said, NanoMarkets believes there is a case to be made for these alternatives to ITO. For one, the markets that ITO serves are quite large and as such even low penetration of these markets will offer large revenue opportunities. In addition, new applications are emerging that magnify ITO's drawbacks. For instance, companies pursuing ITO substitutes see the touch-screen market as a big opportunity; this is not only a large addressable market but one that has an obvious need for a better performing transparent conductor. All one must do to verify this firsthand is walk into a local high-volume retail establishment and attempt to sign on the old, worn-out point-of-purchase display device. ITO cannot stand up to the repeated poking and flexing that is involved with this type of touch screen without deteriorating or cracking.

To quantify this opportunity, NanoMarkets expects the market for ITO to grow from $3.2 billion this year, to $10.9 billion in 2016. Meanwhile, the market for ITO substitutes is expected to grow from about $30 million this year, to almost $940 million in 2016. Such alternatives include other transparent conductive oxides (TCOs), carbon nanotube-based formulations, other nanomaterials, composites, and metals.

In brief, TCOs are an obvious direction to take since they guarantee a cost reduction; unfortunately, TCOs have identical or worse brittleness issues and will never offer the combination of transparency and conductivity offered by ITO. Conductive polymers are inherently flexible, typically can be easily printed, and they cost only a fraction of the price of ITO. An open question is the resilience of this kind of “plastic ITO” when exposed to light in general and UV light in particular. And finally, there's nanomaterials, which share advantages of flexibility, printability, and (usually) cost with organics, and also have a lot of yet-to-be-discovered potential because they are not yet completely understood. Of these ITO alternatives, NanoMarkets sees key long-term opportunities occurring in the nanomaterials sector and the revenues from this type of technology could appear quite quickly in 2010 and beyond.


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Most of the revenues for both ITO and its alternatives will come from rigid liquid-crystal displays (LCDs) and other flat-panel displays (FPDs) throughout the forecast period. Touch-screen displays, however, represent about 10 percent of this market-$324 million in 2009, and growing to $1.2 billion in 2016. As already mentioned, NanoMarkets sees touch-screen displays as a potentially significant opportunity for ITO substitutes. This opportunity will mostly play out in resistive touch screens, which dominate the market. Capacitive touch screens are another story as they do not work by poking with (say) a stylus and therefore are not as vulnerable to ITO's brittleness.

The touch-screens market is not the only game in town for ITO substitutes. There's OLED lighting, which usually uses ITO for its transparent electrodes. Here, in addition to the usual drawbacks of ITO-cost and lack of flexibility-OLEDs can suffer aesthetic shortcomings due to ITO's fairly low conductivity. As such, NanoMarkets expects ITO to lose share of the OLED lighting market fairly rapidly. In its place will be a variety of substitutes including other TCOs at the low end, as well as conductive polymers, carbon nanotubes, and composites.

Indium Tin Oxide and Alternative Transparent Conductor Markets

Table of Contents

Executive Summary E.1 Opportunity Analysis E.1.1 The State of the ITO Market E.1.2 ITO Classic E.1.3 Variations on an ITO Theme: ITO Inks and Nanoparticles E.1.4 Alternatives to ITO: TCOs, Polymers and Nanomaterials E.1.5 Impact on End User Markets: Displays, Lighting and PV E.2 Key Firms to Watch E.3 Summary of Market Forecasts

Chapter One: Introduction 1.1 Background to this Report: ITO in a Time of Deflation 1.2 Drivers for ITO Replacement: Flexible and Touch

Screens, PV and Lighting 1.3 ITO Alternatives: TCOs, Polymers and Nanomaterials 1.4 Objective and Scope of this Report 1.5 Methodology of this Report 1.6 Plan of this Report

Chapter Two: ITO and its Alternatives 2.1 Introduction 2.2 ITO Classic 2.2.1 Extraction and Pricing of Indium: 2009 and Beyond 2.2.2 Indium and Reclamation of ITO 2.2.3 The ITO Business 2.3 Printed ITO, Sol-Gel and Other Manufacturing

Innovations 2.4 The TCO Zoo 2.4.1 ITO, Dopants and Silver 2.4.2 Zinc Oxide as TCO 2.4.3 Tin Oxide as TCO 2.5 PEDOT as ITO Replacement 2.5.1 Advantages and Applications of PEDOT as an ITO

Replacement 2.5.2 PEDOT, Printing and ITO 2.5.3 Disadvantages of PEDOT as an ITO Replacement 2.6 Transparent Conductors and Carbon Nanotubes 2.6.1 CNT Coatings as an ITO Replacement 2.6.2 Research Directions and Likely Improvements in CNT

Coatings 2.6.3 Eikos 2.6.4 Unidym 2.6.5 Regroupement québécois sur les matériaux de pointe

(RQMP)

2.7 Other Nanomaterial Approaches to Transparent Conductors

2.7.1 Cambrios 2.7.2 Sony 2.7.3 University of Michigan 2.8 Key Points from this Chapter

Chapter Three: Applications for ITO and its Replacements 3.1 Introduction 3.2 Conventional LCD Displays: Will ITO Ever

Disappear? 3.3 Touch Screen Displays 3.3.1 ITO and Resistive Touch Screens 3.3.2 ITO and Conductive Touch Screens 3.4 Flexible Displays 3.5 Photovoltaics and ITO 3.6 Lighting 3.6.1. OLED Lighting and ITO 3.6.2 EL Lighting 3.7 Applications for ITO in Conductive and Optical

Coatings 3.8 Key Points in this Chapter

Chapter Four: Market Forecasts 4.1 Forecasting Methodology 4.1.1 What We Have Forecast and Why 4.1.2 Expected Impact of the Financial Meltdown on ITO

and Related Markets 4.1.3 Alternative Scenarios 4.2 Some Notes on Pricing 4.2.1 Basic ITO Products 4.2.2 ITO-Coated Substrates and ITO Inks 4.2.3 ITO-Replacement Products 4.3 Forecast of Basic ITO Sales by Geographical

Region 4.4 Forecasts by Application 4.4.1 Rigid LCDs and Other FPD Displays 4.4.2 Touch-Screen Displays 4.4.3 Flexible Displays 4.4.4 EL and OLED Lighting 4.4.5 Photovoltaics Market 4.4.6 Other Coatings 4.5 Summary of Forecasts of ITO and ITO

Replacements

http://www.nanomarkets.net/products/prod_detail.cfm?prod=10&id=287


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Flexible printed LCDs by Peter Harrop

Dr Peter Harrop PhD, FIEE is chairman of IDTechEx Ltd. He was previously chief executive of Mars Electronics, the $260 million electronics company, and chairman of Pinacl plc, the $100 million fiber optic company. He has been chairman of over 15 high tech companies. He has written 14 books on technical subjects, these being published by the Financial Times, John Wiley and others. He lectures and consults internationally on RFID, smart labels, printed/organic electronics and smart packaging.

A killer new product is one that shows consistent rapid growth in sales at a level that is high enough to be profitable for suppliers. The i-Pod which sold 300,000 in its first year turned out to be one and the Amazon Kindle electronic book looks like being another, with 500,000 sales in its first year. Both are exceptionally easy to use, appealing to the young as trendy and to the old as convenient. For example, electronic books permit the elderly to access a larger font without difficulty and they store one hundred or more volumes in one thin tablet. The text is even more readable in bright sunshine thanks to the electrophoretic display.

It is generally accepted that the next improvement must be the A4 size that is most familiar to those used to paper. This will permit business files to be accessed without tedious reformatting. Then, or so it is thought, the e-books will be further improved by being flexible like paper - even foldable or at least tightly rollable. Such technology would also lead to pull out screens for laptops and mobile phones that snap back into the device when not needed.

Electrophoretics have been successfully printed on polyester films, with printed transistor backplane drivers by Plastic Logic. Indeed, the simpler passive matrix versions have appeared as small displays for such things as shelf edge labels that are updated by radio (SiPix) and samples of ultrathin wristwatches, intelligent key-fobs (Delphi) and other devices have been demonstrated.

Electrophoretic displays deposited on flexible polymer film are commonly referred to as e-paper, the leading supplier of such front planes being a company called E-Ink. The e-paper name is unfortunate because there is now considerable work and some commercialization on electronics including very primitive displays on real paper which can be lower in cost and biodegradable. Genuine paper displays are starting to be used in packaging but they are not suitable for the long life flexible display in electronic equipment. By contrast, electrophoretic displays tolerate wetness and repeated distortion, need no backlight, have good brightness, high contrast, good viewing angle and ultra low power consumption.

However, for years it has been hoped that OLEDs, probably using printed polymeric light emitters and printed polymer or metal oxide transistor backplane drivers would be used for this. OLEDs emit light and have superb color and contrast, narrowest angle of view and fastest video response combined with safe, low voltages. Unfortunately, their chemicals remain extremely fragile and they need electricity even when the image is not changing as with the page of a book. Even their profitable use in television and mobile phones, where they can be protected by glass, continues to be difficult to achieve, absorbing billions of dollars of investment, despite slower, non-printed technology being used to get the show on the road.

Although LCD displays in television have become unprofitable for many suppliers, they are a huge success with about $100 billion annual sales

Experimental bistable, printable, flexible LCD display in a smart card

(Source: Hong Kong University of Science and Technology).


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and huge improvements in picture quality despite an inelegant brushing process being needed on the inside face of the glass sandwich to lock the twisted molecules on which they rely. This creates problems of dust, static and reproducability. Some can be bistable, needing no electricity when the image is fixed and thus preserving power as in today's electrophoretic e-books but that brushing process is not possible with flexible film so the wind-up display is impossible with LCDs.

The desirable color video performance will not therefore be available with flexible e-books if they are made with LCD technology and we must settle for the black and white electrophoretic e-books expected within one year, followed by the rather muddy, slow responding color versions of electrophoretics currently being developed. Or so it was thought until recently. Now several developers have defied this logic by making experimental samples of flexible LCD displays and, although most have serious limitations as yet, they may provide a way forward. The developers have partnerships with major potential users such as Tesco, the UK's largest supermarket chain and Epson.

One of the most promising advances comes from Professor Vladimir Chigrinov at Hong Kong University of Science and Technology. We learnt that experimental LCD “electronic paper” as he calls it, is lightweight, flexible, thin, robust, durable and potentially low cost. We next look at how this is achieved and how it compares with other experimental forms of bistable, flexible LCD.

Bistable flexible LCDs may be an advance on flexible electrophoretic displays for e-books, e-labels and other applications. For example, ability to use any LCD ink can mean that, compared with electrophoretic displays where the whole front plane must be purchased, printing flexible LCDs may lead to lower cost and choice of functions and greater security of supply. When we visited him, we established that Professor Vladimir Chigrinov of Hong Kong University of Science and Technology sees the following opportunities:

Electronic shelf label: 1x3-inch, very low power, color, robust, bar code within, no ghost, price is key E-Book publishing: 6-8-inch, very low power, good reading performances including image transition,

lightweight, price is key E-Newspaper: 10-13-inch, communication, strong performance of layout, high resolution, bendable,

price is key Education market: 8-10-inch, stable and durable, lower price, high resolution, strong interactive

function, no glass material would be better E-Album: 8-10-inch, color, handsome device, lower price, high resolution Professional market: A4 & 10-14-inch, communication and handwriting function, no ghost, bendable.

His process is a roll-to-roll technology using azo-dye photo aligning layers. It does not therefore call for the brushing of glass to make grooves to lock the LCD molecules as seen in today's glass television screens. His process can employ any commercial LCD, including bistable ones to save energy and color versions. Such a display is optically rewriteable by low cost LED. However, although the display is only 500 nanometers thick, the optical rewriting mechanism has yet to be miniaturized. He points out that this arrangement is inherently low cost, likely to give much better colors than electrophoretics, be more robust and operate without need of a transistor active matrix backplane or ITO or alternative transparent electrodes with all their problems of cost and of cracking when bent.

Murayama et al demonstrated a plastic color twisted nematic liquid crystal display (TN-LCD) using a photo-alignment (PA) method. In 2005. A continuous coating with azo dye solution on a plastic substrate and continuous

9-digit reflective flexible TN LCD with SD-1/SDA-2 alignment layer.


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PA treatment was employed. It is confirmed that LC alignment on a plastic substrate is possible under continuous processes.

The left image shows a color LCD by photo alignment. This is a non-contact method providing fine resolution. (Source: Murayama et al). The illustration on the right shows photo-alignment of LCD.

Source: Hong Kong University of Science and Technology

After the alignment of the azo-dye monomers by non-polarized UV, a rewritable procedure, the layer is stabilized by heat polymerization. In the case of Professor Chidrikov's process, this is at 150ºC, so it employs a PES substrate. Lower cost PET may be possible later. The liquid crystal is then deposited on top. The advantages include:

High order parameter with the saturation dependence with exposure time High azimuthal and polar anchoring energy (>10-4 J/m2) Photo- and thermal stability after polymerization (250ºC, 175 MJ/m2) Good adhesion to the glass and plastic substrates Easy pre-tilt angle generation for slantwise non-polarized light exposure (up to 5-100) Easy alignment on curved and 3D surface, super thin tubes and photonic holes Low dosage (150mJ/cm2 for a non-polarized light and 20 mJ/cm2 for a polarized light) Akita University has non-rewritable process using mercury lamps.

Optical image rewriting by photo alignment is carried out by NCKU Taiwan and Kent in the USA but only HKUST has a process tolerant of low cost LEDs we are told. Its azo-dye rotation is unique

On the left is the HKUST optical rewriting process. Work is proceeding on improving the color. On the rights is an image of a color printable flexible LCD. Source: Hong Kong University of Science and Technology


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The image can be hidden, only to be revealed by a polarizer film, so this raises the possibility of anti-counterfeiting. Apparently, this is difficult to fake.

Professor Chigrinov says,

“The earliest commercialization of photo-aligned bistable LCDs will be in flexible displays for plastic cards. All the problems, like mechanical stabilization and electro-optical appearance, have been solved using photo-aligned azo-dye materials. The closest candidates for the application are π-BTN nematic LCD and ferroelectric LCD. The producers of plastic cards in Hong Kong (e.g., Octopus cards) can be approached for the commercialization of our research results. After finishing the project, we are also going to approach LCD companies, that produce flexible displays for mobile phones, smart cards, PDAs, electronic books, etc., for which extremely low power operation is required due to the memory effect. Maintaining and updating the deliverables can be made at the Center of Display Research in HKUST.”

For more see http://www.cdr.ust.hk.

>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<

http://www.idtechex.com/printedelectronicsasia09


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e-Paper Display Technology and Market by Sarah Han

Sarah Han is currently an analyst at Displaybank. Before joining Displaybank, she was working at Samsung Electronics, and has six years experience in the display industry. Sarah has been involved in display marketing and survey activities involving numerous display related companies. At the moment, her research and studies are focused on the flexible display market.

Electronics paper, also called as e-paper, is a reflective display device like a regular paper which requires no self light source and has a native memory function which maintains images, even when the power is off. Most e-papers have outstanding viewing angle and resolution compared to the conventional LCD. They require no back light and can be realized on any substrate such as glass, plastic, metal, and paper. They utilize a simple manufacturing process that enable a low cost roll-to-roll process. In addition, they require power only when changing the screen so they can be operated at low power consumption.

e-Paper is a display which replaces conventional paper prints and expectations are for market growth in applications such as e-newspapers, e-magazines, and e-books. Moreover, it can be applied in public displays such as bulletin boards, advertisement boards, and direction boards.

Technologies to realize e-paper are divided into electrophoretic display, twisted ball display, electrochromic display, Quick Response Liquid Powder Display (QR-LPD), and cholesteric LC which is an extension of MEMS based e-paper technology and LCD technology. However, it is yet difficult to realize a broad color gamut and rapid response time like that of LCD or OLED.

Nonetheless, the e-paper technology has outstanding properties like low-cost, slimness, and stability when compared to other display technologies so that product development applied to this technology is expected to accelerate. Representative e-paper technologies that have reached production stages are as follows:

Electrophoretic Display (E-Ink): Electrophoretic display technology has achieved the most technology development thus far and was developed by MIT Media Lab in 1996. This is a capsule type electrophoretic technology which operates ink corpuscles within a micro-capsule. A structure wraps around the micro-capsule (100~200μm in diameter). After dispersing ink corpuscles of a select color with a select electric charge and ink corpuscles of the other color with opposite electric charge, the micro-capsules are mixed with binder in between electrodes. A negative corpuscle approaches the surface to display the corpuscle’s color when a positive voltage is affirmed, whereas an opposite voltage is affirmed to display the opposite corpuscle color.

E-Ink was established as a spin-off from the MIT Media Labs and uses black carbon-based material on TiO2 corpuscles with outstanding white reflectivity.

Such e-paper technology has outstanding visibility and properties similar to the texture of paper. It also has a memory function to consume extremely small amounts of power. However, the response time is about 100ms, so that full-motion video is not supported. The technology can enable color by adding a color filter, but is still currently in the R&D stage. Initially, a-Si TFT was widely used to realize active matrix e-paper in the past, but many developers now use the active matrix technology using OTFT as developed recently by Philips. The possibility for OTFT’s production applications rises accordingly.


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Twist Ball Type (Gyricon Display): Twist ball type Gyricon displays were developed by Xerox’s Palo Alto Research Center (PARC) for the first time in the 70s. Gyricon sheets comprise a transparent plastic layer in which polyethylene beads of 20~100 microns in diameter float in an oil solution. Half of the beads are negatively charged to display white and the other half are positively charged to display black. In other words, these beads are in a dipole state. They display white and black colors in a rotation method following the affirmed voltage. Xerox established Gyricon Media in December 2000 and although the company disbanded, Xerox still continues the R&D activities. The company recently collaborated with 3M to develop Smart Paper which can be mass produced and delivered the Synchro Sign product, a guide display device using the Smart Paper.

The key technology for Gyricon, which is called Smart Paper, is to switch directions according to the voltage change by attaching black and white planes on a micro-capsule smaller than even sand. Either black or white background can be selected and after-image can be viewed without separate power supply. In addition, micron-capsules are filled between the anode and transparent thin film to allow even 0.1mm to be used in the display screen.

Gyricon display’s operation principal is as follows. Several hundred balls of 30~100μm sizes are dispersed on a silicon elastomer cavity filled with oil in between two sheets of conductive substrate. Here, the dispersed balls are in hemisphere shapes with two strongly oppositive sides. One side is in black to absorb the light, whereas the other side is in white to reflect the light. The white and black areas of the ball possess opposite electric charges so that the ball rotates according to the direction of electric field affirmed from the outside. Such property is used in creating an electric field to allow the black area to locate in the upper part when displaying the black color and allow the white area to locate in the upper part when displaying the white color. At this time, the ratio of ball and oil is nearly the same that the images are maintained for several days even after the affirmed voltage is removed once the ball’s location is secured after it rotates once by the affirmed voltage.

The realization of display resolution and other electro-optical properties vary upon the size of ball. About 100ppi resolution can be realized when the ball size is about 100μm, whereas about 300ppi resolution is realized when the size is decreased to 30μm. The response time and power consumption can be improved but they entail issues of reduced contrast.

Gyricon displays show a 6~10:1 contrast ratio. The operating voltage and switching time for ball rotation are 50~150V and 80~100ms respectively. The operating voltage is relatively higher than other displays and the switching time from white/black is rather long, such that the Gyricon displays have difficulties in realizing motion pictures.

Quick Response Liquid Powder Display (QR-LPD): The e-paper technology using QR-LPD was developed by Japan-based Bridgestone in 2004. The technology is similar to the conventional technology in using electrically charged particles, but its color switching time is very fast at 0.2ms since the ink particles are solid particles that operate as liquid so that the technology draws much attention. In addition, this e-paper technology absorbs and reflects the light close to the surface so that it has a wider viewing angle than the LCD.


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Moreover, the technology uses color filters for colorization. The color filters are located either on the inside or outside of the front substrate and they are created by using either photolithography or ink-jet printing methods. However, there is an issue of having to greatly reduce the operating voltage of over 200V to about 10V in order to commercialize the QR-LPD.

Bridgestone’s QR-LPD trial product

Cholesteric Liquid Crystal Display (Kent Display): In 1993, Kent Display presented e-paper technology using cholesteric liquid crystals which displays colors by selectively reflecting lights of different wavelength. This technology works by inserting cholesteric liquid crystal in between two sheets of glass substrate and affirming voltage to switch between an anti-reflective state and a reflective state.

The e-paper applying Kent Display’s cholesteric liquid crystal does not need color filters and has a stable liquid crystal state so that it consumes no power to maintain the display. In addition, it is light, bendable, unbreakable, and low power consuming. It also has outstanding readability and a wide viewing angle.

Commercialization Trend: The commercialization of e-paper technology progresses following the leadership of US-based E-Ink. E-Ink’s electrophoretic FPL (front plane laminate) is already manufactured in km units through a roll-to-roll process. Segmented displays on plastic substrates are also being produced. E-Ink plans to develop color display with improved response time in 2010. The company currently shows the most active commercialization of flexible display applications and targets to gradually secure the display market by supplying low-cost E-ink displays. E-Ink is expected to show more aggressive activities from now on.

US-based SiPix has independently developed flexible Microcup e-paper which shows outstanding electro-optical properties in 2004. The company launched Flex-It film, the next-generation display product based on Microcup technology, in May 2008. This film offers over 40% enhanced brightness and speed more than twice faster than the conventional products. It is also able to be mass produced through the roll-to-roll process.

Polymer Vision, Philips’ spin-off, has manufactured 5-inch 80ppi rollable active matrix e-paper displays by combining laminated 25μm plastic substrates with E-Ink’s e-paper panel on a 4 mask process solution-based OTFT back plane. The display is about 100μm in thickness and is 7.5mm in radius. The device operates well even after


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several hundred times of bending. In December 2007, the company announced to complete the construction of flexible display factory in Southampton, England and begin mass production. The company also announced that the full production is scheduled to begin in 2H’09.

Plastic Logic, a spin-off from Cambridge University’s Cavendish Lab in 2000, progresses in their developments of ink-jet based OTFT and flexible e-paper backplanes using the OTFT. Using ink-jet processes, Plastic Logic uses a technology that manufactures transistors with high integration without using masks on flexible plastic substrates. The company is also developing an e-book (model name: Reader) with application of this technology. Plastic Logic has constructed a flexible display factory in Dresden, Germany. The company began the line construction in May 2007, competed the facility carry-in by June 2008, and targets to being full production in 2010.

PVI (Prime View International) is a TFT-LCD panel maker established in Taiwan in 1992. PVI collaborated with Philips and entered the e-paper business in 2005. As a result, the company recently has developed LCDs and electrophoretic display based reflective display technology under the name of Magic Mirror. In addition, it plans to manufacture plastic based EPD starting in 2H’09. (And recently acquired E Ink, as noted elsewhere in this newsletter)...

LG Display collaborated with E-Ink and presented B&W 10.1-inch and 6.0-inch color e-paper prototype developments at FPD2005 which was held in Japan. The 10.1-inch e-paper was developed in collaboration with US-based E-Ink. The display has 300μm thickness, 800x600 resolution, 4 grayscale, and 500ms response time. LG Display has presented a 14.1-inch flexible e-book display at SID in 2005. This was the world’s largest flexible product development at that time. This display used the conventional a-Si TFT technology rather than glass on a metal foil to create an active array and applied E-Ink’s technology to realize the e-book. The product has 1280x800 resolution, 16 grey-scales, and 300ms response time. LG Display plans to manufacture 11.5-inch flexible e-paper displays in 2H’09.

e-Paper Display Production Plan by Major Maker

(Source: Displaybank, e-Paper Display Technology and Market Forecast, May 2009)

e-Paper Display Market Forecast: Displaybank projects the e-Paper market to grow from $70 million in 2008 to $2.1 billion in 2015 and $7 billion by 2020 – representing a compound annual growth rate (CAGR) of approximately 47%. Displaybank also projects the e-Book market to comprise 50% of the total e-Paper market during that same period – growing from $35 million in 2008 to $1.1 billion in 2015 and $3.4 billion by 2020 – with the greatest regional demand coming from the US.

2010.1H2009. 2H2009.2H2009.2HMass

Production

Dresden (Germany)

Southampton (UK)

Hsinchu

(Taiwan)Gumi

(Korea)Fab Location

5”

Plastic

E-ink/OTFT

Polymer Vision

Plastic

E-ink/OTFTE-ink /TFT

Panel Maker

Glass/PlasticGlass/ Metal FoilSubstrate

Main Size

Technology

A4 size6” / 8”6” / 11.5”

E-ink / TFT

Plastic LogicPVILG Display

2010.1H2009. 2H2009.2H2009.2HMass

Production

Dresden (Germany)

Southampton (UK)

Hsinchu

(Taiwan)Gumi

(Korea)Fab Location

5”

Plastic

E-ink/OTFT

Polymer Vision

Plastic

E-ink/OTFTE-ink /TFT

Panel Maker

Glass/PlasticGlass/ Metal FoilSubstrate

Main Size

Technology

A4 size6” / 8”6” / 11.5”

E-ink / TFT

Plastic LogicPVILG Display


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e-Paper Display Market Forecast - Revenue


Displaybank also projects e-Paper display demands to grow from 20 million units in 2010 to reach 1.1 billion in 2020. In the existing application market, replacing application for Mobile Display will be commercialized that will grow the demand from 8 million units in 2010 to 320 million units in 2020 showing 48% increase. For the new/emerging application market, the demand is expected to show 63% from 10 million units in 2010 to 800 million units in 2020.

e-Paper Display Market Forecast – Volume


e-Paper Display technology not only has the visual effect of printed paper but it is also able to process information with flexible lower power consumption- These merits of e-Paper Display are expected to lead the e-Paper Display to be widely applied.

-

1,000

2,000

3,000

4,000

5,000

6,000

7,000

2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

Mobile Display Public Display

Others(Replacing) e-Book

Smart Card POP,ESL

Wearable Medical

Others(New)

(Mili.US$)

-

200

400

600

800

1,000

1,200

2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

Mobile Display Public Display

Others(Replacing) e-Book

Smart Card POP,ESL

Wearable Medical

Others(New)

(Unit:Mpcs)


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98


99


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The Last Word… Let there be light!

by Chris Williams

Chris, with his wife and business partner Cathy, was co-founding Director of the highly successful UKDL network and ran the network from April 2006 to March 2009, at which time they chose to pass on the reins of the network to their colleague, Ric Allott. Chris is now developing his wide ranging interests in Plastic Electronics through the consultancy company Logystyx UK Limited that he runs with Cathy, as well as spending more time at the Ceravision company (http://www.ceravision.com) where he is a Director.

One of the pleasures of my job is that I have the opportunity to monitor the progress of some of the Plastic Electronic government-funded projects that are taking place in the UK. This morning I am sitting in the meeting room at Thorn Lighting in their new manufacturing facility in Spennymoor in the north of England, getting ready to monitor the TOPLESS Polymer OLED lighting project that has Thorn, CDT, and University of Durham as the research partners.

The project is going extremely well, but all progress is of course confidential and can’t be reported on here, but – and it is a big “but” – it is great to talk about the future in the midst of the manufacturing environment that is set up around today’s technology. Most of the products manufactured at this site are T5 multi-lamp area luminaires, with annual production of around 5 million square meters of lighting product. Visitors aren’t allowed on the production floor, but through the enormous viewing windows in the upper galley, it is great to watch rolls of painted metal arrive to be punched, drilled, crunched, cut, and bent into shape, with robotic assembly of the driving electronic sub-assemblies and robotic wiring machines.

This is where very large volumes of printed OLED lighting tiles may be used in future years, and it is humbling to understand that most of the output is for domestic use, with “metal bashing” facilities based in most of the major market countries simply because it is cheaper to do local production rather than offshore production and shipping of metal boxes in cardboard boxes. The whole environment bodes well for sometime in the future – but there’s a whole bundle of work that has to be done between now and then!

Part of that work will be watching and then counteracting the inevitable progress of the main competitors to this market – in this case, inorganic LED. Indeed, the whole future of OLED could be undercut at a stroke by the LED makers if they chose to do so. As an example, there is research activity in the UK and elsewhere to develop the ability to develop Gallium Nitride epitaxial layers that can be grown on (cheap) silicon substrates. With GaN currently grown on sapphire, and similar expensive substrates, there has been considerable interest in the “cost down” opportunity that this work has offered. However, in the last few days, massive cuts in the cost of sapphire substrates have been announced effectively removing all commercial benefits from this innovative research. Similarly, with the temporary collapse of the global market for large area LED-backlit TVs, the LED chip-makers have applied their technology to fabricate lighting products instead. T12 fluorescent tube equivalents using hundreds of LEDs will be flooding through onto commercial and domestic markets very shortly. Of great concern to the “high brightness” HBLED makers will be the fact that these new products are simply using high numbers of the smaller non-HBLED chips, incurring extra handling cost but with the LED chips delivered at a fraction of the cost of the HBLEDs themselves.

The above section was written “yesterday”, and this section is written “today”. Here in Manchester I am taking part in the second of three workshops we are holding around the UK to develop input for creating a UK-Industry Strategy for exploiting Plastic Electronics. The first was held in London earlier this week, with delegates from most of the pioneer companies and academic institutions that have underpinned the UK’s leading position in the area. An


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eclectic mix of characters and interests, and a massive spread of data gathered to represent the disparate needs of “simple” through “highly complex” applications. An interesting challenge – combining these wildly varying needs into a single, focused strategy.

Close to the top of our activity list will be the need to extend and strengthen the existing supply chain – simple to say, but much more difficult to do. The exacting need of even the simplest PE architecture requires a process control typically one or even two orders of magnitude greater than most readily available for use in other “non-electronic” markets. Will this be a two-way symbiosis – i.e. will our sector needs drive up standards in these parallel markets, thereby adding value to their current offerings, or will we be alone in needing extraordinary performance? If the former, the commercial imperative is very much in our favor, but if the latter, then supply chain development with “new” partners will be a costly process.

So – interesting times – the global market still in a state of turmoil, banking institutions still being dilatory about lending money to industry, supplies of venture capital finance still scarce – and technologists in our sector continuing to innovate whilst incumbent technologies take unexpected and measures to cut costs and protect their own market existence.

Display Industry Calendar

Go to http://www.veritasetvisus for a more complete calendar and active links. To get your event listed at no cost, feel free to notify [email protected]

July 2009

July 8-10 China International Flat Panel Display Exhibition Shanghai, China

July 8-10 China International Touch Screen Exhibition & Seminar Shanghai, China

July 8-12 International Symposium on Flexible Organic Electronics Halkidiki, Greece

July 8-13 National Stereoscopic Association Convention Mesa, Arizona

July 9 Green Display Expo Washington, D.C.

July 10-13 SINOCES Qingdao, China

July 13-15 Nanosciences & Nanotechnologies Thessaloniki, Greece

July 13-17 International Symposium on Display Holography Shenzhen, China

July 14-16 Semicon West 2009 San Francisco, California

July 14-16 Intersolar North America San Francisco, California

July 16 2009 Small-Medium Display Forum Taipei, Taiwan


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July 19-24 International Conference on Human-Computer Interaction San Diego, California

July 29-30 Japan Forum Tokyo, Japan

August 2009

August 2-7 Chemistry for Electro-optic Displays Symposium Glasgow, Scotland

August 3-7 SIGGRAPH 2009 New Orleans, Louisiana

August 16-18 Australasian Gaming Expo Sydney, Australia

August 20 Printed Electronics Workshop Binghamton, New York

August 31 - September 4 SLIDE 2009 Linz, Austria

September 2009

September 1 Digital Signage 2009 San Jose, California

September 1-5 HCI 2009 Cambridge, England

September 2 TV Conference 2009 San Jose, California

September 3 Touch Conference 2009/Emerging Technology Showcase 2009 San Jose, California

September 3-4 China FPD Shanghai, China

September 4-9 IFA 2009 Berlin, Germany

September 4-9 International Symposium on Wearable Computers Linz, Austria

September 6-9 China International Optoelectronics Expo Shenzhen, China

September 7-10 Foundation in Displays Dundee, Scotland

September 9-13 CEDIA Expo 2009 Atlanta, Georgia

September 9-14 International Stereoscopic Union Congress Gmunden, Austria

September 11-15 IBC 2009 Amsterdam, Netherlands

September 13-16 PLASA '09 London, England

September 14-17 Eurodisplay Rome, Italy

September 20-25 International Conference on Digital Printing Technologies Louisville, Kentucky

September 20-25 Digital Fabrication 2009 Louisville, Kentucky

September 29 - 30 Organic Semiconductor Conference 2009 London, England


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September 29-30 RFID Europe Cambridge, England

September 28 - October 1 Liquid Crystal Displays Oxford, England

September 29 - October 4 CEATAC Japan 2009 Tokyo, Japan

September 29 - October 3 OLEDs World Summit 2009 San Francisco,

California September 30-

October 1 Printed Electronics Asia Tokyo, Japan

September 30 - October 2 Semicon Taiwan 2009 Taipei, Taiwan

September 30 - October 2

Symposium on Applied Perception in Graphics and Visualization Chania, Crete, Greece

October 2009

October 4-7 Symposium on User Interface Software and Technology

Victoria, British Columbia

October 6-8 Semicon Europa 2009 Dresden, Germany

October 6-11 CeBIT Bilisim EurAsia Istanbul, Turkey

October 7-8 Displays Technology South Reading, England

October 7-10 ASID'09 Guangzhou, China

October 12-16 International Meeting on Information Display Seoul, Korea

October 13-14 Asian Solar/PV Summit Seoul Korea

October 13-15 Image Sensors San Diego, California

October 18-21 AIMCAL Fall Technical Conference Amelia Island, Florida

October 19-22 Display Measurement -- Physical and Human Factors Dundee, Scotland

October 19-22 SATIS 2009 Paris, France

October 20-22 LEDs 2009 San Diego, California

October 21-23 Integrated Systems Russia Moscow, Russia

October 26-29 Showeast Orlando, Florida

October 27 Smart Textiles 2009 Dresden, Germany

October 27 Printed Silicon and Hybrids 2009 Dresden, Germany

October 27-29 Plastic Electronics 2009 Dresden, Germany

October 27-29 Solar Power International Anaheim, California

October 27-29 SMPTE 2009 Hollywood, California

October 28-30 FPD International Yokohama, Japan


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November 2009

November 4-5 HD Expo Burbank California

November 5-7 Viscom Milan, Italy

November 9-10 It's Not Easy Being Green Irvine, California

November 9-13 Color Imaging Conference 2009 Albuquerque, New Mexico

November 10-11 Digital Signage Show 2009 New York, New York

November 13 Taiwan TV Supply Chain Conference Taipei, Taiwan

November 16-18 International Workshop on Flexible and Stretchable Electronics Ghent, Belgium

November 23-25 Tabletops and Interactive Surfaces Banff, Canada

November 26-28 China International Touch Screen Exhibition & Seminar Shenzhen, China

November 30 - December 2 International Symposium on Visual Computing Las Vegas, Nevada

flexible substrate

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