On the chemical and mechanical properties of sputtered silicon nitride films

Abstract

Selected chemical and mechanical properties of sputtered silicon nitride films have been studied as a function of deposition conditions. The presence of water vapor in the deposition chamber affects the properties of silicon nitride. This dependence on the chamber conditions can be significantly reduced by ion bombardment of the film during growth. Ion bombardment is thought to preferentially remove residual hydrogen, thus densifying the material. The extreme sensitivity of the etch rate of silicon nitride to relatively small amounts of oxygen present during deposition is demonstrated. When the network connectivity is systematically changed, by the controlled incorporation of hydrogen into the material, the etch rate of the silicon nitride films is shown to correlate with its mechanical wear and scratch properties.