P‐5: Competing Degradation Mechanisms in Flexible Dual‐Gate InGaZnO Thin‐Film Transistor under Mechanical Stresses

The effect of mechanical stress on the electrical characteristics of dual‐gate a‐IGZO TFTs was studied. Identical devices under mechanical stress in different directions exhibited distinctly different degradation behaviors. When the bending axis was perpendicular to the channel length direction, the electrical characteristics of the devices showed a negative threshold voltage shift, counterclockwise hysteresis, and increased on‐state current. When the bending axis was parallel to the channel length direction, a positive threshold voltage shift, clockwise hysteresis, and decreased on‐state current were observed. This indicates the presence of two degradation mechanisms at least, and their relative strengths were determined through dynamic bending experiments with 45° direction to the channel length, the results of which shows the mechanism making transfer characteristics negatively drift is dominant.