Performance of Transparent Indium–Gallium–Zinc Oxide Thin Film Transistor Prepared by All Plasma Enhanced Atomic Layer Deposition

Transparent indium–gallium–zinc oxide thin film transistor (IGZO-TFT) prepared by all plasma enhanced atomic layer deposition (PEALD) has been firstly investigated. As the chemical composition has a considerable impact on the performance of IGZO TFTs, the properties of IGZO film and IGZO-TFT based on different In2O3 cycle ratios are investigated. The IGZO film prepared by PEALD shows amorphous state with excellent conformity and uniformity. Moreover, the a-IGZO films with different In2O3 cycle ratios are applied to TFT fabrication. When the a-IGZO thin film with 35% In2O3 cycle ratios, the transistor presents satisfactory electrical performance with a threshold voltage (
$\text{V}_{\text {th}}$
) of 1.7 V, a saturation mobility (
$\mu _{\text {sat}}$
) of 8.8 cm2/Vs, a subthreshold swing (SS) of 0.2 V/decade and an
$\text{I}_{ON}/\text{I}_{OFF}$
of
$2.2\times 10^{{8}}$
. This work provides a new way to achieve transparent TFT which better for practical commercial applications.