Silicon epitaxial growth process using trichlorosilane gas in a single-wafer high-speed substrate rotation reactor

Abstract

A silicon epitaxial growth process in a trichlorosilane–hydrogen system using a single-wafer high-speed substrate rotation reactor was studied by means of experiments and numerical calculations taking into account the transport phenomena and surface chemical reactions. Hydrogen chloride gas produced at the substrate surface is effectively replaced with the source gases of trichlorosilane and hydrogen, due to the effective mass transport provided by high-speed substrate rotation. Because the intermediate species produced due to chemisorption of trichlorosilane fully occupies the silicon surface, the rate of its decomposition by hydrogen gas governs the entire silicon epitaxial growth rate. Thus, the epitaxial growth rate in this reactor simply depends on the hydrogen gas concentration at the silicon substrate surface.