Improvement in the device performance of tin-doped indium oxide transistor by oxygen high pressure annealing at 150 °C

This study examined the effect of oxygen (O2) high pressure annealing (HPA) on tin-doped indium oxide (ITO) thin film transistors (TFTs). The HPA-treated TFT at 150 °C exhibited a high saturation mobility (μSAT), low subthreshold gate swing (SS), threshold voltage, and Ion/off of 25.8 cm2/Vs, 0.14 V/decade, 0.6 V, and 2 × 108, respectively. In contrast, the ambient-annealed device suffered from a lower μSAT and high SS value of 5.2 cm2/Vs and 0.58 V/decade, respectively. This improvement can be attributed to the decreased concentration of oxygen vacancy defects in the ITO channel layer during the effective O2 HPA treatment, which also resulted in smaller hysteresis and less degradation of the drain current under positive bias stress conditions.