Photo-induced instability and temperature dependence of amorphous In-Ga-Zn-O thin film transistors

摘要

The photo-induced instability of amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) is investigated. Device characteristics under white light illumination with various intensities and its spontaneous recovery at room temperature after illumination are observed. All the observed phenomena, especially the variation of threshold voltage and subthreshold swing, are explained by a simple model based on the photon generated electrons and oxygen vacancy defects in the a-IGZO channel. Further more, the temperature dependence of transfer characteristics for a-IGZO TFTs can be also explained with the same model.