Abstract
Alumina coating films, which were coated on borosilicate glass by a radio-frequency(RF) magnetron sputtering method, were found to be amorphous in a previous work. It was also revealed that the microhardness of sputtered alumina film was larger with increasing RF output in the processing. There was, however, no simple model to explain experimental observations appropriately. In the present paper, the dynamics of rigid spheres was adopted in modeling the formation of amorphous coating film in a sputtering process, and a simulation based on the model was carried out to investigate structural properties of coating film. The volume fraction of deposited particles in coating film was evaluated for various conditions in the simulation, and the dependence of film hardness on RF output was also discussed. The simulated results were found to represent experimental observations qualitatively.