SURFACE-REACTION MECHANISM OF SICL2 WITH CARRIER GAS H-2 IN SILICON VAPOR-PHASE EPITAXIAL-GROWTH

In Si vapor phase epitaxial growth, the rate determining process is considered to be the surface reaction of SiCl2 thermally generated by the decomposition of SiH2Cl2 with the carrier gas H-2. Therefore, the mechanism is studied by using both experimental techniques and ab initio molecular orbital calculations. The experimental results are explained well by the Rideal-Eley model rather than the Langmuir-Hinshelwood model. No meta-stable state is found from the ab initio MO calculations and the reaction rate is simply governed by how thermally active the H-2 molecules are.