Origin of bias-stress and illumination instability in low-cost, wide-bandgap amorphous Si-doped tin oxide-based thin-film transistors

This article reports thin-film transistors (TFTs) with a low-cost, environmentally friendly and wide-bandgap amorphous Si-doped tin oxide (a-STO) semiconductor as the channel layer. To realize practical applications, a comprehensive investigation of a-STO TFTs was performed. The underlying carrier transport mechanism of a-STO TFTs analyzed via the temperature dependence of transfer characteristics is trap-limited conduction. The degradation of the a-STO TFTs induced by bias stress and light illumination is discussed. The results may not only provide a deeper understanding of the electrical properties of a-STO TFTs but also form a fundamental perspective for further improvement of the performance of similar devices. (paper)