SHRI VA ISHNAV INST ITUTE OF TECHNOLOGY AND

SC IENCE

DEPARTMENT OF ELECTRONICS AND COMMUNICATION

GUIDED BY-

Mr. RAKESH GOTHWAL

SUBMITTED BY -

AVINASH KHARCHE(0802EC111022)

FLEXIBLE AND STRECHABLE ELECTRONICS

What if You can Roll your mobile. Drop it. Squish it

in your backpack!!!!

What if you have a embedded display in your

T-Shirt!!!!

INTRODUCTIONThe electronic circuits has driven advances in technology for over a half century. Today your cellphones, computer and even car all rely on the engineering that has made electronics circuit smaller ,faster and smarter ,but circuits are mechanically limited they are rigid.Now several scientists are hoping to change that as a new type of electronic are developing that are FLEXIBLE as humans!!

What are Flexible Electronics?

Flexible electronics, also known as flex circuits, is a technology for assembling

electronic circuits by mounting electronic devices on flexible plastic substrates, such as

polyimide, PEEK or transparent conductive polyester film.

Flexible electronics includes the manufacturing of :-1. flexible printed circuits,2. flexible displays,3. flexible radio frequency identification (RFID) tags,4. flexible sensors,5. flexible batteries and6. devices not yet developed

Methods of building flexible circuit

• It’s a conventional silicon wafer if bend it breaks.If you make it any material thin enough it becomes mechanically flexible so a conventional silicon wafer is .5mm thick but in flexible device it is about 100nm thick because of its thinnes it becomes floppy

Basically there are about 2 methods to building flexible circuit :-1.Silicon Island approach :separate the circuit into parts components that rely on silicon which are rigid and cannot be bend are isolated into tiny squares and connected by a flexible strips of metal ,this grid is then stamped onto an elastic piece by piece .When the circuit is bent the stress is sustain in the thin connectors which have a range of motion while the device island strain a bit but do not break.

2. Buckling Mechanics:Very thin strips of silicon are bonded to a rubber like substrate , that has been pre stretched .when the substrate is then quickly relaxed the silicon buckle but does not break it accommodates the strain by forming a herringbone pattern and in that kind of wave configuration , substrate can stretch in any direction so does silicon.

Organic Light Emitting Diode(OLED)

• OLEDs are solid-state devices composed of thin films of organic molecules that create light with the application of electricity.

• OLEDs - can provide brighter, crisper displays on electronic devices

• Use less power than conventional LEDs or LCDs used today.

OLED Components

• Like an LED, an OLED is a solid-state semiconductor device

• 100 to 500 nanometers thick OR about 200 times smaller than a human hair

• OLEDs can have either two layers or three layers of organic material;

An OLED consists of the following parts:

1.Substrate - supports the OLED.

2.Anode - removes electrons when a current flows through the device.

3.Conducting layer - transport "holes" from the anode.

4.Emissive layer- transport electrons from the cathode; this is where light is made.

5.Cathode - injects electrons when a current flows through the device.

How do OLEDs Emit Light?

OLEDs emit light in a similar manner to LEDs, through a process

called electrophosphorescence.

OLED Advantages

OLEDs offer many advantages over both LCDs and LEDs:

• Thinner, lighter and more flexible than LED or LCD.

• Lower cost in the future• Wider viewing angles about 170

degree & improved brightness• Better power efficiency• OLEDs are brighter than LEDs• OLEDs are easier to produce and

can be made to larger sizes. • Video images could be much

more realistic.

OLED seems to be the perfect technology for all types of displays, but it also has some problems:

•Lifetime - While red and green OLED films have longer lifetimes (46,000 to 230,000 hours), blue organics currently have much shorter lifetimes (up to around 14,000 hours).

•Manufacturing - Manufacturing processes are expensive right now.

•Water - Water can easily damage OLEDs

Disadvantages

Applications of OLEDs1. Displays for mobile phones and

portable digital media players, 2. Digital cameras.3. In heads-up displays,

automotive dashboards, billboard-type displays, home and office lighting.

4. The newspaper of the future might be an OLED display and like a regular newspaper, you could fold it up when you're done reading it, stick it in your backpack or briefcase.

Future aspects and applicationsof flexible and strechable electronics

1.Stretchable electronic skin could connect an artificial hand to the nervous system. 2.Combat uniforms and helmets containing flexible, lightweight impact sensors could help medics prescribe better treatment if a soldier is wounded in an explosion.

3.A neuroscientist who wants to understand the electrical storm that occurs in the brain can use flexible circuit.4.Flexible circuits would also make portable devices more resilient; they could be worn like clothing or jewellery rather than carried5.Flexible solar cells have been developed for powering satellites.

.

• It is, in short, possible to see how logic circuits, input sensors, output displays and power supplies can all be made in flexible form. Many firms and scientist are working and it is likely to be some time before you are offered a mobile phone in the form of a flexible rubber bracelet, a smart tattoo attached to your skin, or even an implant that flexes along with your body.

Flexible and Stretchable electronics is the Next Big

Thing!!!!

Thank you!