The characteristics including intrinsic property of a‐Si ‐TFT and LTPS TFT for the application used as OLED backplane are reviewed. Though a‐Si AMOLED shows better uniformity and is capable of driving OLED, the stability of a‐Si TFT under operation is still not acceptable, while LTPS TFT reveals satisfactory stability in AMOLED application. The stability of TFT under long‐term operation is remained to be the key issue for commercialization of a‐Si TFT AMOLED.

We have successfully demonstrated a 4.0 inch full‐color active matrix OLED display based on amorphous Si a‐Si TFT, and incorporating high efficiency phosphorescent materials. The use of a red phosphorescent sub‐pixel reduced display power consumption by 42%, compared to a comparable display based on only fluorescent materials This demonstration clearly shows the possibility of using a‐Si TFT as driving backplanes for the manufacture of full color AMOLEDs