Effects of mechanical strain on A-Si:H TFT electrical stability

The electrical stability of hydrogenated amorphous silicon thin-film transistors (a-Si:H TFTs) on flexible substrates is characterized under uniaxial tension and compression applied by bending. TFTs under compression(tension) experience enhanced(reduced) degradation under moderate constant-voltage gate bias (<2MV/cm) compared to without applied strain, with ~5% more(less) reduction in IDS after 104s. After removal of bias stress, TFTs released similar percentages of trapped charge over time regardless of applied strain conditions. The stretched-hyperbola model for defect creation in a-Si:H TFTs was fitted to measurement data and used to predict how applied strain can affect TFT lifetime in practical applications.