Amorphous-silicon thin-film transistors deposited by VHF-PECVD and hot-wire CVD

We investigate the impact of new growth techniques on the mobility and stability of amorphous silicon (a-Si:H) thin film transistors (TFTs). It was suggested that the key parameter controlling the field-effect mobility and stability is the intrinsic mechanical stress in the a-Si:H layer. We study a series of bottom-ate TFTs incorporating a-Si:H deposited by VHF PECVD and hot-wire CVD. All TFTs exhibit good characteristics with mobilities of 0.6-0.7 cm(2)/V s. The mean activation energy EA and the slope of the barrier-height distribution kBT, for defect creation in the a-Si:H are determined, E. correlates to the intrinsic stress. (C) 2002 Elsevier Science B.V. All rights reserved.