High-Performance Indium–Gallium–Zinc Oxide Thin-Film Transistors Based on Anodic Aluminum Oxide

Thin-film transistors (TFTs) based on indium-gallium-zinc oxide (IGZO) active layer and anodic aluminum oxide (Al₂O₃) gate dielectric were investigated. The anodic Al₂O₃ gate dielectric possesses low leakage current and relatively high dielectric constant. The IGZO TFT based on anodic Al₂O₃ shows a mobility of as high as 21.6 cm²/V·s, an on/off current ratio of as high as 10⁸, and a threshold voltage of only 2 V. Further studies show that the anodic Al₂O₃ gate dielectric is very compatible with the IGZO semiconductor, and both the channel resistance and contact resistance are lower than those of the TFTs based on thermally grown SiO₂ gate dielectric.