Analysis of the Hydrogen Reduction of Silicon Tetrachloride Process on the Basis of a Quasi-Equilibrium Model

Abstract

The process for the growth of silicon single crystals by the hydrogen reduction of silicon tetrachloride has been described using a model which assumes that chemical equilibrium obtains at the silicon deposition site. The thermodynamic calculations by Lever for the equilibrium gas phase composition in the Si-C1-H system (primarily H2, HC1, SIC12, SiHCl3) were used to calculate the growth rate of silicon as a function of mole fraction silicon tetrachloride input and temperature in an open tube system. Some of the features of the experimental results reported in the literature are predicted by the equilibrium model. The results are discussed in relation to similar calculations by Steinmafer who did not take the species SiHCl~ into account. © 1964, The Electrochemical Society, Inc. All rights reserved.