Unveiling the Oxygen Vacancy Mediated Ternary Relationship among Field-Effect Mobility, Photoresponse, and Negative Bias Stress Stability in Indium Zinc Oxide Thin-Film Transistors via Dual-Path Modulation.

This study systematically reveals an intrinsic ternary trade-off among field-effect mobility (μFE), photoresponse, and negative bias stress (NBS) stability in amorphous indium zinc oxide (IZO) thin-film transistors (TFTs). Precise control over oxygen vacancy (VO) concentration and amorphous microstructures is achieved through two independent modulation strategies involving N2 doping and sputtering target composition adjustment. Comprehensive electrical characterizations demonstrate that VO acts as a primary controlling factor within the structurally stable amorphous network, while the overall relationships is additionally bounded by defect-state redistribution and network disorder. While an optimal VO concentration significantly promotes μFE and photoresponse through enhanced carrier density and efficient photogeneration, NBS stability is simultaneously compromised by intensified defect-assisted charge trapping and carrier ionization. This trade-off persists regardless of whether the modulation induces monotonic or nonmonotonic behaviors. These findings provide critical physical insights and design guidelines for tailoring oxide TFTs to diverse application-specific requirements.