Suppression of Hysteresis in Amorphous IGZO Thin-Film Transistors via Defect State Passivation

Abstract

In this work, a systematic investigation of hysteresis-free charge transport in amorphous indium-gallium-zinc oxide thin-film transistors is presented through strategic interface engineering. Devices were fabricated via RF sputtering with controlled oxygen partial pressure (5-15%) and a double Al₂O₃/SiO₂ gate insulator deposited by atomic layer deposition, followed by thermal annealing at 300°C. Optimal performance was achieved at 10% O₂ content, exhibiting threshold voltage shifts below 0.05 V, eliminating hysteresis within experimental error. The transistors demonstrated exceptional electrical characteristics including high electron mobility, ON/OFF ratios exceeding 10⁸, and remarkable stability under bias stress. This work establishes a viable pathway toward reliable, high-performance oxide semiconductors for next-generation display and flexible electronics applications.