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 $V_{O}$ .