Stability of amorphous-silicon TFTs deposited on clear plastic substrates at 250 °C to 280 °C

Amorphous-silicon (a-Si) thin-film transistors (TFTs) were fabricated on a free-standing new clear plastic substrate with high glass transition temperature (T-g) of > 315 degrees C and low coefficient of thermal expansion of < 10 ppm/degrees C. Maximum process temperatures on the substrates were 250 degrees C and 280 degrees C, close to the temperatures used in industrial a-Si TFT production on glass substrates. The first TFTs made at 280 degrees C have dc characteristics comparable to TFTs made on glass. The stability of the 250 degrees C TFTs on clear plastic is approaching that of TFTs made on glass at 300 degrees C-350 degrees C. TFT characteristics and stability depend only on process temperature and not on substrate type.