Characteristics of sputtered Y-doped IZO thin films and devices

Yttrium-doped IZO(YIZO) thin films with different thickness have been prepared on soda-lime glass(SLG) and P-Si substrates by radio frequency magnetron sputtering at room temperature. Structural morphology and optical properties of the films have been investigated. YIZO thin film transistors(TFTs) with the bottomgate-structure are fabricated on P-Si substrates. The output and transfer characteristics of YIZO-TFT have been studied. It has been found that all YIZO thin films prepared at room temperature are amorphous, and the YIZO TFTs exhibit n-channel depletion mode. YIZO-TFT with active layer thickness of 20 nm shows an on/off ratio over 105, a sub-threshold swing of 2.20 V/decade at a low operating voltage of –1.0 V, and saturation mobility values over 0.57 cm2/(V·s).