The Oxidation Process in Silicon Nitride

This paper summarizes studies undertaken to elucidate the intrinsic oxidation behavior of silicon nitride, both by itself, and in relationship to the other key silicon-based ceramic, silicon carbide. Results presented here include oxidation rates, and some effects related to the formation of a compositionally graded suboxide interlayer during the oxidation of silicon nitride. A unique, noninterfacial oxidation mechanism is shown to account for those effects.