TRANSPARENT ACTIVE MATRIX ORGANIC LIGHT-EMITTING DIODE (OLED) DISPLAY

DRIVEN BY NANOWIRE TRANSISTOR

Presented by:

VIGNESH CDSP 2st sem10MT61DS22

CONTENT1. INTRODUCTION2. ORGANIC LED (OLED)3. NANOWIRE TRANSISTORS4. FABRICATION PROCESS5. EQUIVALENT CKT FOR A SINGLE ACTIVE PIXEL6. NW-AMOLED DISPLAY DEVICES7. ADVANTAGES & DISADVANTAGES8. APPLICATIONS 9. CONCLUSION10.REFERENCE

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INTRODUCTION

Optically transparent, mechanically flexible displays are

attractive for next-generation visual technologies and portable

electronics.

In principle organic light-emitting diodes (OLEDs) satisfy key

requirements for this application.

However, to realize transparent, flexible active-matrix OLED

(AMOLED) displays requires suitable thin-film transistor (TFT)

drive electronics, Nanowire transistors (NWTs) are ideal

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ORGANIC LED (OLED) OLED is a solid-state semiconductor device that is 100 to 500

nanometers thick or about 200 times smaller than a human hair.

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An OLED consists of the following parts:

1.Substrate.

2.Anode.

3.Organic layers.

-Conducting layer.

-Emissive layer.

4.Cathode.

HOW DO OLED EMITS LIGHT

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NANOWIRE TRANSISTORS

The circuitry required for each AM display pixel must

contain

3 nano wire transistor.

-one switching transistor.

-two driver transistor.

-storage capacitor, with appropriate scan and data lines to

allow selective pixel addressing.

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FABRICATION PROCESS The fabrication begins with a 200 nm thick SiO2 layer deposited on

glass substrates.

Next, a 100 nm ITO thin film is deposited by ion-assisted

deposition & subsequently patterned by photolithography.

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Next, a 22 nm layer of SAND is

deposited on the patterned ITO

gate electrodes via solution self-

assembly.

ITO S–D electrodes are then

deposited by IAD. Next, a 200 nm thick SiO2 layer is deposited by e-beam evaporation.

FABRICATION PROCESS Now expose the PLED ITO anodes, and PEDOT-PSS is spin-coated.

TPD–Si2 + TFB polymer blend HTL + EBL is spin-coated.

Then, a well-balanced charge transport/emissive layer (EML), a TFB

+ F8BT blend is spin-coated.

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Inside of a glovebox, LiF and Al

are thermally evaporated onto

the EML .

The NW-AMOLED devices are

then encapsulated with glass

using an UV-curable epoxy.

PDOT:POLY ETHYLENE DIOXY THIOPENE

PSS: POLY STYRENE SULFONATE

TFB+TPD-SI2: POLY DIOCTYL FLUORENE CO METHYLPROPYL

TFB+F8BT: POLY DIOCTYL FLUORENE CO

BENZOTHIODIAZOLE

LIF: ELECTRON INJECTION LAYER

EQUIVALENT CKT FOR A SINGLE ACTIVE PIXEL

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Consists of

-one switching transistor (T1)

-two driving transistors (T2 and T3).

-one storage capacitor (Cst).

NW-AMOLED DISPLAY DEVICES

Figure A,B & C shows a magnified image of the array at various

values of the data line voltage Vdata is for 1, 2, and 3 V.

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Figure D & E shows optical images of a 15 pixel × 8 pixel array

with selective pixel line addressed independently by controlling

Vdata line.

Fig A Fig B Fig C

Fig D Fig E

FULLY TRANSPAREANT NW-AMOLED DISPLAY ELEMENTS

• Fig 1shows an Optical image of a fully transparent NW-AMOLED

substrate.

• Fig 2 shows an Optical images of a 2 × 2 mm NW-AMOLED

array.

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ADVANTAGES Transparent OLED provides higher refresh rate and

consumes less power.

Slimmer.

Faster.

Good for Eyes.

Large Viewing Angle.

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DISADVANTAGES

Transparent oled is difficult to view in sunlight.

Short lifetime.

Highly Water prone.

High Cost.

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APPLICATIONS Military application: top emitting oled (TOLED).

Commercial Applications

-contact lens

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APPLICATIONS

• Light car

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CONCLUSION

Transparent OLED is a technology of future.

This technology is certainly going to find a way for itself if

not now then in future.

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REFERENCE Photo physics of Organometallics Arvind Kumar, Shih-Sheng

Sun, and Alistair J. Lees

Madelung, O., Ed. Technology and Applications of

Amorphous Silicon; Springer: Berlin, 2000.

www.wikipedia.org/organic_led

www.oled-info.com

oled-display.net/how-works-the- oled-technology

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Thank you

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ANY QUESTIONS

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