A Study of the Acclerated Degradation Phenomena on th Amorphous Silicon Thin Film Transistors with Multiple Stress

복합 스트레스에 의한 비정질 실리콘 박막 트랜지스터에서의 가속열화 현상 연구

The accelerated degradation phenomena in amorphous silicon thin film transistors due to both electrical stress and visible light illumination under the elevated temperature have been investigated systematically as a function of gate bias, light intensity, and stress time. It has been found that, in case of electrical stress, the thrshold voltage shifts of a-Si:H TFT's may be attributed to the defect creation process at the early stage, while the charge trapping phenomena may be dominant when the stressing periods exceed about 2 hours. It has been also observed that the degradation in the device characteristics of a-Si:H TFT's is accelerated due to multiple stress effects, where the defect creation mechanism may be more responsible for the degradation rather than the charge trapping mechanism.