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 (Al
₂
O
₃
) gate dielectric were investigated. The anodic Al
₂
O
₃
gate dielectric possesses low leakage current and relatively high dielectric constant. The IGZO TFT based on anodic Al
₂
O
₃
shows a mobility of as high as 21.6 cm
²
/V·s, an on/off current ratio of as high as 10
⁸
, and a threshold voltage of only 2 V. Further studies show that the anodic Al
₂
O
₃
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 SiO
₂
gate dielectric.