Studies on the effect of hydrogen doping during deposition of Al:ZnO films using RF magnetron sputtering

Aluminum doped ZnO (ZnO:Al) films were deposited using rf magnetron sputtering in the presence of hydrogen gas in the chamber. A comparative study of the films deposited with and without hydrogen was performed. The XPS studies indicated that the decrease in resistivity of ZnO:Al films with the introduction of hydrogen gas is attributed to the reduced adsorption of oxygen species in the film grain boundaries. The average percentage transmission in the visible region of the films was around 92-95% and band gap was found to be about in the range of 3.15-3.17 eV. The lowest resistivity of 1.8 × 10−4 Ω cm was achieved for the ZnO:Al film deposited with hydrogen.