semiconductor presentation revised us
TRANSCRIPT
Based on a review article written by: Tsuyoshi Sekitani, Hiroyoshi Nakajima, Hiroki
Maeda, Takanori Fukushima, Takuzo Aida, Kenji Hata and Takao Someya which was
published on 10th May, 2009 in Nature Material this presentation aims at introducing
what printable elastic conductors are and how they can be used in the varied field of
semiconductors for the better use of humanity.
Stretchability will significantly expand the applications scope of electronics,
particularly for large-area electronic displays, sensors and actuators. Unlike for
conventional devices, stretchable electronics can cover arbitrary surfaces and
movable parts.However, a large hurdle is the manufacture of large-area highly
stretchable electrical wirings with high conductivity. Here, we describe the
manufacture of stretchable active matrix OLED display using printable elastic
conductors.
Active-matrix is basically a type of addressing scheme (pixel state) used in flat panel
displays like LCD TV screens.
Recently new technologies have been emerging in the field of “stretchable”
electronics like the development of elastic electrical wiring that is both highly
conductive and highly stretchable . Although there have been examples of these kind
of materials been made like graphene films coated with metal; problem that has arose
is to find a procedure to make such materials larger in size. One solution to this
problem that has been provided by the authors in this article is to develop printed
elastic conductors which are extraordinarily conductive and use that to construct a
rubber-like stretchable active-matrix display.
What do one exactly mean by a printed elastic conductor?
The authors provide a technique of producing stretchable OLED’s by using the principle of
direct printing technologies i.e. printable inks that have high conductivity and stretchability
to make printed elastic conductors which consists of fine SWNT bundles uniformly
dispersed in a highly elastic fluorinated rubber matrix which is quite viscous. The
chemically stable SWNTs (high purity) act as highly conductive dopants and help in
forming well developed conducting networks in rubber.
Advantages of printed elastic conductors
No requirement of any kind of extra coating of metal unlike other conductors (e.g.
graphene films)
No requirement of any huge mechanical process unlike others like wavy thin metals
It can stretch by a huge margin (118%)
Has an extraordinarily high conductivity (102 S/cm)
Basic idea of organic light emitting diode
After making the elastic conductors the authors explains a process of manufacturing
Organic LEDs and organic driving cells separately on PDMS sheets which are then
joined together to form a highly stretchable display.
An active matrix was then fabricated on a flexible polyimide film using a special process
called vacuum evaporation.
By integrating the active matrix and organic LEDs using printed elastic conductors a
stretchable active-matrix Organic LED display was finally manufactured.
Bending or crumpling causes no mechanical or electrical damage because of the
excellent conductivity and mechanical durability of the printed elastic conductors ,
organic transistors organic LEDs manufactured on the special rubber.(PDMS rubber)
The stretchable materials and manufacturing technology like printed
electronics used in this study can also be used to create other types of
useful electronics such as rubber-like electrical artificial skin with a
stretchable active matrix and pressure sensors. The combination of
stretchable sensors and displays can be used to create real, tangible
displays and user-friendly human-machine interfaces on all kinds of
surfaces and of shapes. Active research is still being done in this regard
by many international electronic companies like Visionox and Samsung.
Research on finding materials regarding these types of printed
conductors is going on in full flow by well-known scientists in major
universities like Stanford University , Yale University etc.
Thus we can find that, the printable elastic conductor developed in this work enables the
construction of electronic integrated circuits that can spread over any surface including
curved and movable parts. This would significantly expand the areas where electronics
can be used. This is an important step towards the development of the infrastructure for
the coming era of ambient electronics in which a large number of electronic devices such
as sensors and display networks function as user friendly human-machine interfaces that
can be used in daily life to enhance security, safety and convenience and also as
wearable technology.
REFERENCE WEBSITES
www.nanowork.com
www.cse.whk.edu.hk
www.ftp.priceton.edu
www.en.wikipedia.org
www.86wiki.com
www.ncbi.nim.gov/pubmed
www.m.wisegreek.com/whatisjetmilling
www.users.wfu.edu
www.fredlake.com
www.ieexplore.ieee.all
www.rubberworld.com
www.freedictionary.com
www.rsc.com
www.vipsmail.1.blogspot.in
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