A Mathematical Model of Silicon Chemical Vapor Deposition: Further Refinements and the Effects of Thermal Diffusion

Abstract

We describe a mathematical model of the coupled gas‐phase chemical kinetics and fluid mechanics in a chemical vapor deposition (CVD) reactor. This paper presents refinements to our earlier model of the CVD of silicon from silane. The model predicts gas‐phase temperature and velocity fields, concentration fields for seventeen chemical species, and deposition rates. The major new features are a multicomponent transport model including thermal diffusion and a new formulation of the boundary conditions that describe deposition. A significant result is that thermal diffusion is predicted to make an important contribution to species density profiles and generally to reduce deposition rates.