We have studied the impact of off-bias stress on the performance of thin film transistors (TFTs) fabricated on single crystalline silicon-on-glass substrates. The p-channel TFT transfer characteristics typically exhibit excellent on-state performance with a field-effect mobility of 203 cm(2)/V s and a subthreshold swing of around 200 mV/dec. However, the off-state drain current has increased with increasing gate voltage. This increasing off-state current phenomenon can be significantly reduced by performing an off-state bias for 10 s. The formation of electron traps in the gate oxide near the drain is the main factor that reduces the off-state leakage current. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3416325] All rights reserved.