Kodak Receives 2008 OLED Display Technology Leadership Award

Eastman Kodak Company has been named by Frost and Sullivan as the recipient of the 2008 North American Technology Leadership Award in the field of Organic Light Emitting Diode (OLED) Display Technology.  

The Emerging Technologies Awards are bestowed annually based on a survey and analysis of companies that have pioneered the development and introduction of innovative technologies into their markets. The awards recognize companies for successful technology developments that are expected to bring significant contributions to their industries in terms of adoption, change, and competitive posture. Kodak, a pioneer in the OLED field, is recognized for its knowledge and experience in the area of device architecture, manufacturing solutions, and development of OLED materials for Active Matrix OLED (AMOLED) displays. This award recognizes Kodak as a leader amongst several major AMOLED display companies worldwide.

“Kodak’s goal is to continue to lead the way in AMOLED innovation and to partner with other leading companies to commercialize this very promising technology,” said Andrew Sculley, General Manager and Vice President, Kodak’s Display Business.  “We are thrilled to be recognized by a well-respected organization such as Frost & Sullivan and we look forward to proudly displaying this award, and demonstrating our other OLED advances, in our exhibit at the upcoming Society for Information Display Conference in Los Angeles, California (May 18th –23rd).”

Highlights of the technical areas pertaining to the award are summarized below:

OLED Device Architecture Solutions:  Kodak’s proprietary approach to providing highly stable, manufacturable AMOLED displays utilizes a white emitting OLED architecture.   In this method, a four sub-pixel (RGBW) is utilized, with the color being provided by appropriately filtering the white emission.  Compared to the conventional approach of pattering the individual RGB emitters, the white-based architecture offers advantages in manufacturability as well as higher levels of operational stability and color gamut. In particular, the white-RGBW (W-RGBW) architecture avoids the differential aging problem commonly encountered with the direct patterned emitter approach, which typically results from the more rapid degradation of the blue emitting sub-pixel (compared to the red and green. Kodak’s W-RGBW approach does not suffer from this problem because Kodak’s white emitting structure is highly stable and the white spectrum does not shift in color during long term operation.  Hence the color emitted by the OLED display remains constant over time.  “Based on years of experience, we believe that the path to a low-cost, high-performing AMOLED display is through the use of the WOLED (white-emitting OLED) architecture.  The benefits include scalability, no need for shadow mask, lower manufacturing cycle time and better production yield.  This technology is also directly applicable for future solid-state lighting applications,” said Dr. James Buntaine, Chief Technology Officer and Vice President of Kodak’s Display Business.

OLED Manufacturing Solutions: A key benefit of Kodak’s approach is the ability to simplify the fabrication process. Typical RGB OLEDs are patterned using fine metal masks, which limit the overall processing size to about half the size of a Gen 4 sized glass plate. Anything larger usually leads to distortion in the fine metal mask, with consequent mis-registration of the deposited organic materials. The W-RGBW approach, on the other hand, does not require fine metal masks because the white OLED is deposited uniformly across the entire substrate and the color filters required with the white OLED approach are patterned using conventional, high-yield photolithography. This allows the entire process to be scaled-up without any significant manufacturing obstacles.   In fact, modeling indicates that Gen 8 (and larger) sizes should be achievable.

OLED Yield Improvement Solutions: A challenge often encountered in OLED displays is the variations in luminance across the emitting surface caused by non-uniform currents being supplied to the individual sub-pixels, caused by thin-film-transistor (TFT) related processing issues.  To overcome this, Kodak developed Global Mura Compensation (GMC) to detect and compensate such irregularities in the TFTs using an external driver IC.  This scheme avoids the requirement for within-pixel compensation and is a very flexible approach that has been recognized as a preferred approach by others in the AMOLED industry.

“Several AMOLED small panel companies are very interested in learning more about GMC technology in an effort to increase their production yields and thus provide additional, high quality AMOLED panels into the market,” said Corey Hewitt, Operations/Marketing Manager and Vice President, Kodak’s Display Business.  “We have recently demonstrated this technology’s ability in the 3” KODAK ELITE VISION, the world’s thinnest, lightest, portable AMOLED 1-Seg TV.”

This product, co-developed by Kodak, LG Display, KAGA Electronics and Andes Electronics will be available in Japan by the end of March 2008.

Another challenge impacting OLED yield is due to poor OLED material utilization during manufacturing.  Kodak’s proprietary Vapor Injection Source (VIS) technology enables low cost OLED manufacturing by increasing OLED materials utilization to greater than 50%, increasing organic deposition rates and thus reducing manufacturing cycle times (to 2 min or less), and increasing equipment up-time to greater than 85%. In addition this deposition technology has been demonstrated at Gen 5 scale and is scalable to Gen 8 and larger substrates.  The technology also enables high yield and easier manufacturing control due to low degradation multi-component deposition from a single source, eliminating out of spec depositions due to incorrect layer compositions or thermal degradation of organic materials.

Material Development to Fuel Future Growth of OLED Improvements: Critical to the success of the OLED display industry is the introduction of improved materials and architectures.  Kodak is a leader in this effort, developing improved materials and architectures that continue to provide significant advances in AMOLED displays.   For full-color pixilated RGB displays, new materials in development at Kodak provide outstanding lifetime and power consumption. In particular, high-efficiency blue and green dopants that reduce the operating current density; and stable host materials for blue and green emitters have recently been developed.  Also, Electron Transporting Layer (ETL) and Electron Injection Layer (EIL) materials have been developed that enable low OLED voltage and high power efficiency.  

These materials, in combination with the W-RGBW pixel architecture provide advanced displays low power consumption, greater than 100% NTSC x,y color gamut, and are estimated to have a half-life much greater than 100,000 hours (over 11 years of continuous operation).  Kodak has also been an innovator in the development of phosphorescent emitting systems.