We demonstrate critical elements of a-Si technology on clear plastic for flexible AMOLED applications. First, we show that a-Si TFT’s with gate voltages under 5 V provide sufficient current for OLED pixel brightness of over 1000 cd/m2, with minimum geometries (W/L = 1) for 100 µm × 100 µm pixels. Critical to this result is a clear plastic with the combined properties of high transparency, glass transition temperature in excess of 300oC, and low coefficient of thermal expansion. Second, we show that by engineering the a-Si TFT stack, under the bias conditions for pixel operation, the “half-life” of the TFT (defined as the time for the current to fall by 50% in DC operation) is 10 years for a 280oC process on clear plastic, and at least 100 years for 300oC. This is several orders of magnitude higher than that of common a-Si TFT processes and in general larger than the lifetimes for the 50% decay of the luminescence of the OLED’s themselves. Finally, we provide a framework demonstrating the tradeoff between drive current and TFT stability.
|Original language||English (US)|
|Number of pages||4|
|Journal||Digest of Technical Papers - SID International Symposium|
|State||Published - 2009|
|Event||2009 Vehicles and Photons Symposium - Dearborn, MI, United States|
Duration: Oct 15 2009 → Oct 16 2009
All Science Journal Classification (ASJC) codes