Three-Dimensional Modeling Of Thermal Oxidation Of Silicon By Means Of The Finite Element Method

A numerical model which is suitable to describe three-dimensional thermal oxidation of silicon is proposed. By oxidation the three material components silicon, silicon dioxide and oxidant molecules are involved. The model takes into account that the diffusion of oxidants, the chemical reaction, and the volume increase occur simultaneously in a so-called reactive layer. This reactive layer has a spatial finite width, in contrast to the sharp interface between silicon and dioxide in the convential formulation. The oxidation process is numerically described with a coupled system of equations for reaction, diffusion, and displacement. In order to solve the numerical formulation of the oxidation process the finite element scheme is applied.