Preparation and optoelectronic properties of a-IGZO thin films deposited by RF magnetron sputtering at different working pressures

Transparent oxide semiconductor, a-IGZO, thin films were prepared by high-vacuum RF magnetron sputtering at different working pressures. The effect of working pressure on crystal structure, surface morphology, and electrical and optical properties of the films was studied. The highest hall mobility of 17.45 cm 2 ·V −1 ·s −1 is obtained at 0.3 Pa with annealing at 200 °C, while the highest carrier concentration of 2.32 × 10 20 cm −3 and the lowest resistivity of 0.001568 Ω·cm are obtained at 0.45 Pa with annealing. The highest transmittance of 90.9 % is obtained at 0.9 Pa with annealing treatment. A “blue shift” of UV absorption edge is observed with the increase of working pressure.