A power rate law study of silicon germanium selective vapor phase epitaxy kinetics

Abstract

The selective vapor phase epitaxy (SVPE) kinetics of a Si 1− x Ge x heterostructure is complex. To date, operational kinetics schemes are not available and reactant interactions are not very well understood. This study is a phenomenological investigation of epitaxial film growth rate (GR) and composition. An empirical model is developed specifically to address the kinetics of industrial SVPE processes performed at a pressure above 1 Torr. The response function investigated in this study is very similar to the one applied in the field of heterogeneous catalysis. The relevance of a power rate law (PRL) to Si 1− x Ge x SVPE is assessed with the goodness of fit as well as with a consistency check of the fitting parameters with the chemistry of the process. Despite the lack of a reaction scheme supporting the PRL, trends consistent with the known chemistry of growth kinetics are evidenced, thus confirming the soundness of the method. Partial reaction orders are identified for HCl, SiH 2Cl 2, GeH 4 and B 2H 6.