Reaction mechanism of silicon Cat-CVD

Reaction kinetics for the silicon catalytic chemical vapor deposition (Cat-CVD) has been investigated. SiH3 and Si2H2 are expected to be important precursors in the Si film growth. However, the reactivity of Si2H2 to the film surface was not well understood. Quantum chemical calculations have been performed for the adsorption of Si2H2 and H2SiSiH2 on the Si(1 0 0)-2 × 1 surface with and without the hydrogen termination. It was found that there was no activation barrier for the Si2H2 adsorption on the bare Si(1 0 0) surface. The chemical kinetic model for the Si Cat-CVD process was modified according to these quantum chemical calculations. Results of kinetic simulations were compared to the experimental results. It is suggested that there is a correlation between the film quality and the concentration of Si2H2.