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Ho Kyoon Chung, Ph.D.

Vision for Roll-to-Roll

Manufacturing of Plastic

AMOLED

1

Contents

2. AMOLED, the Ultimate Display

3. Plastic AMOLED by Sheet to Sheet

4. Vision for R2R AMOLED

1. Motivation 1. Motivation

2

My Motivation

Key Success of Semiconductor Industry

Continuing the productivity improvement

By wafer size increase

Adding more values

By increasing the speed and level of

integration

3

My Motivation

Challenges of FPD Industry

How to continue the productivity improvement

By increasing glass size ?

Adding more values

By larger displays ?

4

My Motivation

The Answer : Roll to Roll AMOLED !

Higher productivity

By continuous process and

lower investment

Adding more values

By new form factors

5

Strong points of AMOLED: Self-Emissive Organic Display and

large color gamut, fast response time, slim, and can be made by R2R!

Image quality

AMOLED

Robustness (physical, temp.)

Cost & thickness

Color gamut Viewing angle

AMOLED: True Ultimate Display!

6

Successful Commercialization Since 2007

OLED display size is increasing from 4” to 5” and larger

OLED display is moving to higher resolution

March 2007

Iriver CLIX MP3

2.2” 320×240

AMOLED

July 2010

Samsung AMOLED

4.0” 800×480 WVGA

Super AMOLED

June 2009

Samsung Haptic

2.8” 400×240 WqVGA

AMOLED + Touch

March 2007

KDDI MediaSkin

2.4” 320×240

AMOLED

General Trend

Feb. 2012

Samsung AMOLED

5.3” 800x1280 WXGA

Super AMOLED

7

55” OLED TV’s at CES International 2012

8

- Frequently Asked Question,

“What is the next big thing after OLED TV?”

Plastic AMOLED!

9

Flat Conformable

Bendable Rollable Foldable

Wall Paper (Large Screen)

Display

Substrate

Application

Glass Thin Glass/Metal Foil Plastic Sheet Plastic Roll

Samsung

Signage

TV

(Displaybank)

Display Revolution: Glass Plastic

Samsung

Flat Conformable Foldable Rollable Wall Paper

Glass Metal Foil Plastic Sheet Plastic Roll

Sony

Samsung

We Are Here,

“Ultra Thin, Unbreakable” When?

10

Plastic Display Evolution

Mobile Displays : Ultra Thin & Light-weight/ Unbreakable (UT/UB)

Big Screen with Portable Size (Foldable/Rollable)

Final Goal: Large Size Rollable TV

Foldable Rollable TV UT / UB

11

Challenges of Plastic AMOLED

Key Challenges: 1) TFT Same as On-Glass

2) Low Cost Thin Film Encapsulation

3) Compatible with Existing Fab

Plastic Substrate

Plastic Substrate

- Moisture Barrier

- Delamination After Completion

TFT Process Architecture

- Low Temp. TFT Process

- TFT with High Reliability

Thin Film Encapsulation

- Processing Time

- Cost of Ownership

Carrier

Thin Film Encapsulation

- Throughput

- Scalability

TFT Process Architecture

- Low Temp. TFT Process (?)

- TFT with High Reliability

12

Plastic as AMOLED Substrate

Thermal Stability

Barrier on Top and Bottom

Lamination/Delamination without defect

Step Issue Metal Foil Plastic

Substrate preparation

Surface planarization Required -

Diffusion barrier against moisture and oxygen

- Required

TFT array

Thermal stability Stable Can Be Stable

Overlay alignment Poor Good

OLED FMM alignment Poor Good

General Flexibility Marginal Excellent

Issues

13

Plastic AMOLED by Sheet to Sheet

① PI Film Lamination ② AMOLED Processing ③ Delamination

Glass

Plastic Film

Glass

Plastic Film

Thin Film Encapsulation

AMOLED TFT

Glass

Plastic Film

Thin Film Encapsulation

AMOLED TFT

Laser Irradiation

14

Plastic AMOLED, Same Quality

as on Glass !

15

Pro: Compatible with Glass Fab

Con: Higher Cost

Plastic AMOLED by Sheet to Sheet

① PI Film Lamination ② AMOLED Processing ③ Delamination

Glass

Plastic Film

Glass

Plastic Film

Thin Film Encapsulation

AMOLED TFT

Glass

Plastic Film

Thin Film Encapsulation

AMOLED TFT

Laser Irradiation

16

Key Challenges of Plastic AMOLED Manufacturing

Thin Film Encapsulation

Scalability to Large Size

Maintaining Thin Form Factor

Manufacturing Innovation by R2R

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Key Challenges of Plastic AMOLED Manufacturing

Thin Film Encapsulation

Scalability to Large Size

Maintaining Thin Form Factor

Manufacturing Innovation by R2R

18

Vitex Technology for Thin Film Encap.

“Vitex” BarixTM coating

Poly

Poly

Inorg

Poly

Poly

Inorg

Inorg

Poly

Inorg

Inorg

Inorg

Poly

• Cluster process

• High equipment cost

• Limited scalability

• Long tact time

• Physical interfaces

• Inferior film quality

Vitex Technology for Thin Film Encapsulation

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Susceptor

`

Substrate

Pumping

RP

Reactor

(1)

Remote-plasma Module

RP

Reactor

(2)

RP

Reactor

(3)

RP

Reactor

(4)

RP

Reactor

(5)

RP Reactor Array

5X throughput

RP

Reactor

(5)

120mm

* Nozzel: 3.5G

▪ Linear Cavity-type Reactor : Excellent Uniformity

▪ Extremely Small Chemical Consumption :Low Mat’l Cost

▪ Scanning :High Throughput

▪ Closed-Loop Controlled Reactor : Atmospheric Press.

• High throughput

• Atmospheric process

• Low temperature

• Short tact time

• Superior film quality

New Concept ALD/PP* Process

PP*: Plasma Polymer

Sungkyunkwan University

2012. 8. 27 20/15

WVTR of Al2O3/plasma-polymer multilayer barriers

0 5 10 15 20 25 300.00

0.25

0.50

0.75

1.00

No

rma

lize

d c

on

du

cta

nc

e (

1/R

)

Time (hour)

Al2O

3(20nm)

Al2O

3(10nm)/PP(100nm)-2dyads

Al2O

3(5nm)/PP(50nm)-4dyads

Al2O

3(2.5nm)/PP(25nm)-8dyads

Total thickness : 220nm (P.P 200nm/Al2O3 20nm)

2.5nm Al2O3

25nm P.P

5nm Al2O3

50nm P.P

10nm Al2O3

100nm P.P

<1.0ⅹ10-5 g/(m2·day)

21

Manufacturing Innovation: R2R for AMOLED

Source: PolyIC

Advantages:

• Lower Investment

• Continuous Processing

• Flexible Substrates

Challenges:

• TFT Backplane

- Fine Patterning, Performance

• OLED Printing

- In-line Processing

• R2R Encapsulation

R2R by Printing Technology:

Very Challenging for TFT Backplanes !

Smallest feature size typically 20-100 µm depending on process

throughput, substrate and ink properties

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Suggestions of Technology Development for R2R Plastic AMOLED

TFT Array:

-Transfer Printing of Completed Pixel Array

OLED :

- Vacuum Evaporation Using Linear Source

- Nozzel Printing

Encapsulation:

- ALD/PP R2R

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Transfer Printing of TFT Array

400 500 600 700 800 40

50

60

70

80

90

100

ZnO TFTs on PDMS

PDMS

)

-

1mm

-

Wave length(um )

2

Fabricate TFT on SL

Dissolve SL & Lift off TFT

Transfer to Substrate

Release

Transmittance

TFT Array on Flexible Substrate

SL : Sacrificial Layer (Ge)

25

ZnO TFT Array Layout

TFTs Arrays

Source

Drain

Gate

Pour for

Water

Penetration

Device covered by

SU-8

Encapsulated TFT Arrays

26

TFT Array on Roller

TFTs Arrays on

Roller

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TFT Characteristics after Transfer

28

Roll to Roll Printing Machine

- R2R Transfer Equipment for 20x20cm TFT Array

- 100 % Transfer Yield Confirmed

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Process Flow Block Diagram for R2R AMOLED

Pixel Circuit Fabrication

Transfer Printing

Inter-connection

Anode

PDL

Common, RGB, ETL

Cathode

Thin Film Encapsulation

Module

30

對外秘

30

對外秘

Ex.: Roll-to-Roll Manufacturing of OLED Lighting

31

I Have a Dream: Plastic AMOLED by R2R in 2019!

“I say to you today, my friends, that in spite of the difficulties and frustrations of the moment, I still have a dream. It is a dream deeply rooted in the American dream.”

-Martin Luther King, Jr

August 28, 1963

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Conclusion

1) AMOLED is the Ultimate Display for Future World

2) Flexible AMOLED on Plastic Substrate Has Been Developed

3) TFT Array Transfer Printing by Sheet to Roll is Demonstrated

4) Future Vision and Challenge of R2R Manufacturing of AMOLED is

Addressed

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Rollable AMOLED !

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Thank You!