Effects of post-annealing in hydrogen atmosphere on the properties of Al-doped ZnO films

Transparent conductive ZnO:Al (AZO) films were deposited on glass substrates by radical assisted magnetron sputtering. The effects of post-annealing in hydrogen atmosphere on the Al doping efficiency and properties of AZO films were investigated. It was found that post-annealing treatment improves the Al doping efficiency and reduces the concentration of neutral impurity scattering centers. These two factors together improve the conductivity of AZO films. The resistivity and the transmittance at 550 nm of the AZO films annealed in H2 at 550 ℃ were 65×10-4 Ω·cm and 857%, respectively, with carrier concentration being 33×1020 cm-3 and mobility of 297 cm2·V-1·s-1.