To study and compare the effects of γ  ray irradiation and atomic oxygen (AO) treatment on the prop-
erties of ZnO:Al (ZAO) films, two groups of ZAO film samples were prepared by direct current magnetron sputtering. Films in the first group were irradiated by γ  ray. Films with different thicknesses in the other group were treated with AO. The microstructures, morphologies and electrical properties of ZAO films before and after the treatments were characterized by modern advanced methods. It is found that high dose of ray irradiation decreases the crystallinity of ZAO films, while irradiation with low rate has an annealing effect.γ  ray can also excite the electrons, resulting in the increase of the carrier concentration. The highest ratio of increase reaches 16. 39%. AO treatment has oxidation effects on the surface of ZAO films, leading to the increase of the content of crystal lattice oxygen. The carrier concentration is accordingly decreased and the ratio of the decrease drops as the film thickness grows.