LARGE-AREA INTEGRATED SUBSTRATE FOR OLED LIGHTING

O L E D T r a c k S e s s i o n D o E S O L I D S T A T E L I G H T I N G M A N U F A C T U R I N G R & D W O R K S H O P , S a n D i e g o , C A

C h e n g - H u n g H u n g , D e n n i s O ’ S h a u g h n e s s y , A s h t o s h G a n j o o , J a m e s M c C a m y , A b h i n a v B h a n d a r i

P P G I n d u s t r i e s

May 7, 2014

OUTLINES

Introduction

Integrated substrate

Internal Extraction Layer (IEL)

Anode

Summary

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THE BIG PICTURE DoE Program Goal: Substantial energy savings

Reference

OLED LED

Quad

s of

Ene

rgy

Source: DoE Report- Energy Savings Potential of SSL in General Illumination, 2010

Scenario 2015 2020 2025 2030 Cumulative

OLED 0.01 0.36 0.96 1.51 10.49

$ Saving* (Billion)

0.085 3.06 8.16 12.84 89

Potential U.S. Energy Savings in Quads

*Assumption: 1 Quad Production~ $8.5 Billion

1 quad/yr energy saving needs ~3 x 109 ft2 OLED panels#.

3 # Assuming 0.17 ft2/w, 120 lm/W, and 50% efficiency improvement

A typical float glass line produces ~3 x 108 ft2 glass per year.

Cover up 52,000 football fields

Need 10 float lines

0510152025303540

0%

5%

10%

15%

20%

25%

30%

35%

Cost

($/m

2 )

Cost

(%)

DOE Targeted OLED Material Cost

MATERIAL COST AND SUBSTRATE SIZE

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20

30

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Area

(m2 )

Shor

t Sid

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imen

sion

(in)

Substrate Generation

OLED Substrate Size Trend

2007

2011

Source: DOE SSL Manufacturing Roadmap, 2013

~40% for integrated substrate

Need for low cost, large area integrated substrates. Float glass manufacturing process can meet this need. 4

Float line glass dimension

Previous DOE Project Accomplishments

• Demonstrated 73% efficiency increase possible using a combination approach (IEL+EEL)

• Current project, Manufacturing process for OLED integrated substrate, is supported by US Department of Energy (DE-EE-0006261).

DOE R&D Award DE-EE0003209

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CURRENT DOE PROGRAM

Objectives: Manufacturing process development of a low-cost “integrated” float glass based substrate product for large area OLED panel lighting. Cost Target: $60/m2 by 2015 and $28/m2 by 2020

Performance Target: 50% extraction efficiency

enhancement; 10-15 ohms/sq sheet resistance (lower with grids)

2 Years manufacturing process development program in partnership with UDC and Plextronics started in August 2013.

Device Manufacturing & Testing

Hole Injection Layer (HIL) Application & Screening

Integrated Substrate Manufacturing

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IEL/EEL and Anode Metrics METRICS

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IEL/EEL Metrics Project Goals

Light Outcoupling Efficiency 50% enhancement for IEL & EEL Combination

Surface Quality Compatible with device manufacturing

Chemical and Mechanical Durability

Stable against buffer and light emitting materials Compatible with OLED processing

Anode Metrics Project Goals

Low Resistance & High Transmission

10-15 Ω/� and 85% transmission across visible spectrum

Work Function > 5eV

Surface Roughness < 10 nm RMS (without planarizing layer) RPeak to Valley < 50 nm (without planarizing layer)

Chemical Migration Electrochemically stable in contact with cathode material No migration of conductive particles

Chemical and Mechanical Durability

Stable against buffer and light emitting materials Compatible with OLED processing

Deposition Defects <<1 Pinhole of 0.5 µm/mm2

PPG Integrated Manufacturing Process

Both IEL and anode layer (TCO) applied in a low-cost float glass manufacturing process.

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IEL Tool CVD Coater

Sketch of float glass manufacturing process

PROGRESS ON INCORPORATION OF LIGHT SCATTERING ELEMENTS

Glass samples made in an on-line process A lab sample with targeted haze

• Glass samples illuminated with an edge light

Significant progress on on-line IEL development toward target requirements.

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CVD ANODE TECHNOLOGY

On-line produced transparent conductive oxide (TCO) is crystalline. Large crystals give better sheet resistance and poorer surface roughness.

(a crystalline material)

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PROGRESS ON SMOOTHENING ANODE SURFACE

Without smoothening oxide layer

• Scanning Electron Microscope (SEM) planar view images

Smoothening oxide layer used in on-line anode manufacturing process.

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With smoothening oxide layer - Improved 20% on Rq and ~30% on Rp-v

HOLE INJECTION LAYER (HIL) Purposes

• Planarization of rough substrates, thereby preventing shorts between anode and cathode, increasing yield, and reducing cost

• HIL materials can improve hole injection and extend device lifetimes

Sketch of HIL on anode Devices fabricated on anode without HIL (left) and with HIL (right)

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SUMMARY

The state of the art in the lab has progressed significantly.

IEL trials with the pilot are in progress, with significant improvement of embedding and better understanding the challenges.

Smoothening oxide layer is used in on-line anode process. OLED lighting performance is being evaluated.

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