Highly Stable, Solution‐Processed Ga‐Doped IZTO Thin Film Transistor by Ar/O2 Plasma Treatment

Abstract

AbstractThe effects of gallium doping into indium–zinc–tin oxide (IZTO) thin film transistors (TFTs) and Ar/O2 plasma treatment on the performance of a‐IZTO TFT are reported. The Ga doping ratio is varied from 0 to 20%, and it is found that 10% gallium doping in a‐IZTO TFT results in a saturation mobility (µsat) of 11.80 cm2 V−1 s−1, a threshold voltage (Vth) of 0.17 V, subthreshold swing (SS) of 94 mV dec−1, and on/off current ratio (Ion/Ioff) of 1.21 × 107. Additionally, the performance of 10% Ga‐doped IZTO TFT can be further improved by Ar/O2 plasma treatment. It is found that 30 s plasma treatment gives the best TFT performances such as µsat of 30.60 cm2 V−1 s−1, Vth of 0.12 V, SS of 92 mV dec−1, and Ion/Ioff ratio of 7.90 × 107. The bias‐stability of 10% Ga‐doped IZTO TFT is also improved by 30 s plasma treatment. The enhancement of the TFT performance appears to be due to the reduction in the oxygen vacancy and OH concentrations.