Hydrogen-induced improvements in electrical characteristics of a-IGZO thin-film transistors

摘要

This study investigates the effect of hydrogen incorporation on amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs). The threshold voltage (V) and subthreshold swing {SS) of hydrogen-incorporated a-IGZO TFTs were improved, and the threshold voltage shift (AVth) in hysteresis loop was also suppressed from 4 V to 2 V. The physical property and chemical composition of a-IGZO films were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy, respectively. Experimental results show that the hydrogen-induced passivation of the interface trap states between active layer and dielectric is responsible for the improvement of SS and Vth.