Robust performance and stability of In2Оз thin-film transistors with atomic-layer-deposited channels

Abstract

Atomic-layer-deposition (ALD) ln20 3 thinfilm transistors (TFTs) were fabricated under a maximum processing temperature of 200 °C. In order to reduce the concentration of oxygen vacancies in the ln20 3 channel, 0 2 plasma treatment was carried out on the TFTs by plasmaenhanced chemical vapor deposited (PECVD). The ln20 3 TFT treated at 200 °C for 240s exhibited good performance such as a field-effect mobility of 11 cm2/Vs, a threshold voltage (Vth) of 0.9 V, a subthreshold swing of 0.38 V/dec, and an on/off current ratio of 107 In addition, the device exhibits a small negative threshold voltage shift (A Vth) during negative gate bias stress. However, it showed a more pronounced A Vth under positive bias stress with a characteristic turnaround behavior from a positive A Vth to a negative A Vth. The positive AV m is attributed to the charge trapping effect, and the abnormal negative AVth should due to the hydrogen incorporated into the film.