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 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /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.