An Oxygen Gettering Scheme for Improving Device Mobility and Subthreshold Swing of InGaZnO-Based Thin-Film Transistor

Abstract

This study involved developing a low-power and high-mobility metal-oxide thin-film transistor that incorporated a bilayer IGZO/IGZO:Ti semiconductor material. Compared with control metal-oxide TFTs, the bilayer IGZO TFT through thickness modulation of IGZO: Ti can reach the smallest subthreshold swing (85 mV/decade) and the highest field effect mobility (49 cm(2)/Vs) at a drive voltage of <3 V. This performance level improvement can be attributed to the gettering effect caused by the IGZO: Ti capping layer and its dual advantages, which enhance device mobility and improve gate swing.