Numerical Analysis of Incident Angle Effects in Reactive Sputtering Deposition of Amorphous SiO2

Abstract

Effects of the incident angle of deposition species on film properties during reactive sputtering deposition processes for amorphous SiO2 are examined with the use of molecular dynamics (MD) simulations combined with Monte Carlo (MC) simulations. From the simulation results, it has been confirmed that some properties of the deposited film strongly depend on the incident angle of Si atoms sputtered from the target. For example, the film density is shown to become lower at larger Si incident angles. The stoichiometry of the film expressed by the ratio of the number of O atoms to that of Si atoms contained in the film has been also shown to increase as the Si incident angle increases. In other words, as the angle of incidence for Si atoms becomes large, the film becomes more oxygen rich and porous. Possible physical mechanisms causing these effects are also discussed from the viewpoint of motion of incident Si atoms interacting with the surface atoms.