Abstract: HfO₂ film with the thickness of 7.8nm is deposited on p type silicon by using atomic layer deposition method, and aluminum is sputtered on top of the HfO₂ film to form Al/HfO₂/Si MOS structure. The surface morphology of HfO₂ is taken by using atomic force microscopy, and the surface quality is approved to be high with low surface roughness and high uniformity. The radiation induced oxide and interface trapped charge density are in the order of 10¹²cm^-2, which is larger than that in SiO₂ with the same equivalent oxide thickness. Moreover, the radiation induced oxide trapped charge density increases with the increase of irradiation total dose, the radiation induced interface trapped charge can be either positive or negative. The chemical structure of the HfO₂ film is measured by XPS and oxygen vacancy is found to be the dominant radiation induced traps inside the film HfO₂.