The annealing induced extraordinary properties of SI based ZNO film grown by RF sputtering

ZnO thin films were prepared by RF magnetron sputtering method on SiO2/Si(111) substrate at different ratio of Ar/O2, which were annealed at different annealing temperatures to improve the films’ quality. The effects of the ratio of Ar/O2 and annealing treatment on the ZnO films’ properties were discussed. The crystal structures and surface morphologies of ZnO thin films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD results show that the as-deposited films have dominant c-axis orientation and the quality of ZnO films is better when grown with the gas ratio of Ar/O2 is 1:1. After the annealing treatment, the quality of the ZnO thin films was improved. The annealing treatment induces the change of grain size and lattice expanding, which induced the strengthening of the band-edge emission at around 371 nm.