Drain Current Response to Fast Illumination Pulse for Amorphous In-Ga-Zn-O Thin-Film Transistors

Abstract

In this paper, the characteristic of the amorphous indium-gallium-zinc-oxide thin-film transistors under steady bias and fast multiple-pulse illumination stress is analyzed. The change in the drain current (Delta I-D) with respect to time is measured under different light intensities and pulse frequencies. The mechanism is proposed to explain the results by correlating the oxygen vacancy (V-O) reacting with the light-induced electron-hole (e-h) pairs. The results can be well analyzed by the fitting formula and parameters for the different light pulse frequencies. The tendency proves that not all the V-O react with e-h pairs at the same reaction rate. It is observed for the first time the number of V-O with fast reaction decreases with the pulse frequency. A model is proposed to describe the relation between the number and reaction rate of V-O.