Light illumination effect in AIZTO/IZO dual-channel TFTs

In oxide thin-film transistors (TFTs), light illumination effect is a big concern due to its operating condition. Light illumination can change many electrical properties in oxide TFTs such as mobility and threshold voltage (V_th). In many researches, Oxygen vacancy is suspected as a main cause of the changes by light illumination. Recently, the back channel formation by field-induced macroscopic barrier model is reported under light illumination. This is also related to Oxygen vacancy. In this letter, we investigate the gradual changes in DC and CV characteristics depending on the dual-channel thicknesses. For this purpose, we use the aluminum-doped indium zinc tin oxide (AIZTO)/indium zinc oxide (IZO) dual-channel TFTs. The main goal of this paper is to find the main cause of the changes by light illumination in various dual-channel thicknesses.