Recent several years, ZnO thin film has attracted much more attention due to its promising electrical, optical and piezoelectric properties, which can be extensive apply in electronic and optoelectronic fields such as optical waveguides, solar cell, gas sensors, etc. Especially, ZnO is a wide-band gap of 3.37 eV and high efficiency as a low-voltage cathodoluminescent phosphor material in backlight for field emission display. Among the many fabrication techniques of ZnO film, magnetron radio frequency sputtering is considered as a convenient method to deposition homogeneous ZnO thin film on large area. In this research, we will compare the phosphor properties of ZnO film by post-thermal treatment in different gas ambient.