Analysis of Wet Etching Characteristics of a-IGZO Thin Film

Abstract

Amorphous InGaZnO (a-IGZO) films are deposited on the glass substrate by RF sputtering and the influence of wet etching of a-IGZO films, etching rate, over etching features and TFT structure chose are investigated. The results show that Oxalic acid is best chose for IGZO film etching for side etching is about 0.1um , etching rate is 7.42 A/s which is easy to control and taper angle is acute. The traditional G-I-D type structure has been confirmed is not fit for the condition where the IGZO based TFT manufacture. G-D-I structure is tested and can be used in the TFT array manufacture.