Effects of Oxidants on the Bias-Stress Instabilities of In-Ga-Zn-O Thin Film Transistors Using HfO2 Gate Insulator Prepared by Atomic Layer Deposition

摘要

We fabricated the In-Ga-Zn-O thin-film transistors using HfO2 gate insulator prepared by atomic-layer deposition with different oxidants of H2O and O-3 at 200 degrees C. While the device using H2O showed almost no change in threshold voltage (V-th) even after $10<^>{{4}}$ s with bias-stresses, the device using O-3 showed the V-th shifts of -1.4 and +1.2 V under positive and negative bias stresses, respectively. Defect-related carrier generation model was suggested as a physical origin for the anomalous bias-stress instabilities and the related mechanisms, in which the incorporated hydrogens can interact with oxygen-related defects.