標題: ANOMALOUS BIAS-STRESS-INDUCED UNSTABLE PHENOMENA OF HYDROGENATED AMORPHOUS-SILICON THIN-FILM TRANSISTORS
作者: TAI, YH
TSAI, JW
CHENG, HC
SU, FC
電子工程學系及電子研究所
Department of Electronics Engineering and Institute of Electronics
公開日期: 23-十月-1995
摘要: Thin-film transistors (TFTs) with different silicon nitride (SiNx) gate compositions and various hydrogen concentrations in their amorphous silicon films (a-Si:H) have been stressed with positive and negative biases to realize the instability mechanisms. For both stress polarities, it is found that the threshold voltage shifts significantly increase due to the trap sites in the SiNx gate. As the effects of the trapped charges in the SiNx films are reduced, the anomalous threshold voltage shifts under negative stress voltage are observed. The creation of the states near the conduction band in the a-Si:H films can be enhanced according to the defect pool concept and stimulated by the hydrogen contents in the a-Si:H films, which can be confirmed by the subthreshold swing change. Therefore, the negative threshold voltage shifts caused by the hole trapping in the SiN, gate are positively compensated by the created states, reflecting the turnaround behaviors for the threshold voltage shifts. As for the positive stress, the state creation in the a-Si:H films can be suppressed via the defect pool mechanism and thus the threshold voltage shifts are dominantly affected by the electron trapping in the SiNx gates. (C) 1995 American Institute of Physics.
URI: http://dx.doi.org/10.1063/1.114439
http://hdl.handle.net/11536/149149
ISSN: 0003-6951
DOI: 10.1063/1.114439
期刊: APPLIED PHYSICS LETTERS
Volume: 67
起始頁: 2503
結束頁: 2505
顯示於類別:期刊論文