OLED Advantages

OLED: Potential Advantages

- Thin, lightweight, printable displays

- Low voltage, low power, emissive source

- Visibility at all lighting levels

- high brightness

- good contrast

- High resolution (< 5 ìm pixel size)

- Fast switching (1-10 ìs)

- Broad color gamut

- Wide viewing angle

- Low bill of materials

Early Applications of OLEDs:

Importance of Display Attributes

Optimal Applications of OLEDs:

Importance of Display Attributes

OLED Strategic Decisions

Roadmap Theme

•Passive matrix OLEDs are of limited interest

•< 240 lines and 4”??

•Active matrix OLEDs could replace LCDs

•Lower materials costs

•Fast response

•Lower weight and thickness

•Lower power

•Plastic substrates will follow (3 years later?)

•Conformable displays

•Flexible displays

Three Stages of AM-OLED Development

•Stage 1 - 2004

•Limited volume production

•Acceptable performance for some products

•Relatively high manufacturing costs

•Stage 2 - 2007

•Performance competitive with LCDs

•Cost competitive with LCDs

•Stage 3 - 2010

•Performance exceeding that of LCDs

•Cost lower than LCDs

System Performance Targets

Basic Diode Performance Targets

Diffuse Lighting Applications

For lighting applications, one can focus upon

-conversion efficiency

- device stability and lifetime

- material selection and optimization

- encapsulation

- uniformity over large areas

- manufacturing costs.

For lighting applications, one does not need

- fine patterning

- contrast

- pixel switching

- color saturation.

Diffuse Lighting Performance Targets

Highlights of Recent Progress

•System performance

•Materials

•Deposition and patterning

•Fabrication plans

•Flexible OLEDs

Progress in System Performance

•Large area panels

• 17” (1280x768) from Toshiba

•Power consumption

•Sanyo Kodak - 2W for 5.5” display @ 200 cd/m2

•High contrast at 500 lux

•40:1 by Idemitsu Kosan

•200:1 by Sony

•Emission through transparent cathode

•Sony 13” (800x600) panel

Progress in Material Development

•Saturated blue in Sony 13” prototype

•CIE coords (0.15,0.06)

•Stable blue from Idemitsu Kosan (0.14, 0.17)

•10,000 hour half-life from 200 cd/m2 (eff: 4.7 cd/A)

•Phosphorescent red from UDC/PPG (0.65,0.35)

•9 cd/A @ 500 cd/m2

•6000 hour half-life from 500 cd/m2

•Green dendrimer from Opsys Research Lab

•Solution-processable small molecule system

•51 cd/A @ 100 cd/m2 and 4.1V

 

Source: Damoder  Reddy at  Opsys

Progress in Deposition and Patterning

•Smooth ITO from Unaxis and others

•No spikes above 4 nm in height

•Vacuum deposition of small molecules

•Organic Vapor Phase Deposition from Aixtron

•Linear evaporation sources from Ulvac and Lesker

•Shadow masks with 5 ìm precision

•Ink-jet printing of polymers

•30 mm sub-pixels (70 mm pitch) by Seiko-Epson

•Custom systems available from Litrex/Spectra

      Most current systems are aimed at 350-400

Plans for Fabrication of AM-OLEDs

•Small Molecule systems

•eMagin -Samples of microdisplays (HMD) 2001

•SK-Samples from 300x400 mm line at Gifu in 2002

•SK-Production from 550x670 line in Tottori in 2003

•Pioneer - limited production in 4Q2002

•Sony - ready for production in 2003

•Polymer systems

•Toshiba from pilot line in 2Q2002 (Fukaya)

•DuPont - first products in 2004

•Others

         •SNMD - samples in 2003, commercialization in 2004

Data from company interviews and presentations 2001/2

Flexible OLEDs

•Passive matrix prototypes from

                     DuPont           and            UDC

•Progress on coatings for plastic substrates by Vitex

Conclusions

•Material performance is improving rapidly

•lifetime & efficiency need more work

•Production costs present greatest challenge

•throughput, substrate area, yield & uptime

•capital costs for TFT array equipment

•drive electronics

•Innovation is still needed

•materials

•pixel structures

•fabrication processes

•Long term pathway to new devices

•thin -> conformable -> flexible

Article  by

J .Norman  Bartstey

U.S. Display  Consortium