Effects of preparation parameters on growth and properties of β-Ga2O3 film

Abstract

The Ga2O3 films are deposited on the Si and quartz substrates by magnetron sputtering, and annealing. The effects of preparation parameters (such as argon–oxygen flow ratio, sputtering power, sputtering time and annealing temperature) on the growth and properties (e.g., surface morphology, crystal structure, optical and electrical properties of the films) are studied by x-ray diffractometer (XRD), scanning electron microscope (SEM), and ultraviolet-visible spectrophotometer (UV-Vis). The results show that the thickness, crystallization quality and surface roughness of the β-Ga2O3 film are influenced by those parameters. All β-Ga2O3films show good optical properties. Moreover, the value of bandgap increases with the enlarge of the percentage of oxygen increasing, and decreases with the increase of sputtering power and annealing temperature, indicating that the bandgap is related to the quality of the film and affected by the number of oxygen vacancy defects. The I–V curves show that the Ohmic behavior between metal and β-Ga2O3 films is obtained at 900 °C. Those results will be helpful for the further research of β-Ga2O3 photoelectric semiconductor.