Anomalous on-current and subthreshold swing improvement in low-temperature polycrystalline-silicon thin-film transistors under Gate bias stress

Abstract

This work investigates an improvement in anomalous on-current and subthreshold swing (SS) in Low-temperature polycrystalline-silicon thin-film transistors after positive gate bias stress. The experimental results reveal that the improved electric properties are due to the hole trapping at SiO(2) above the lightly doped drain regions, which causes a strong electric field at the gate corners. The effect of the hole trapping is to reduce the effective channel length and the SS. Besides, the stress-related electric field was also simulated by TCAD software to verify the mechanism above. (C) 2011 American Institute of Physics. [doi:10.1063/1.3568895]