The chemisorption and reaction of dichlorosilane on Ge(100) and Ge(111) surfaces

Abstract

The reactions of dichlorosilane (SiCl2H2) with Ge(100) and Ge(111) are investigated with soft X-ray photoelectron spectroscopy excited by synchrotron radiation. SiCl2H2 is found to dissociatively chemisorb at all temperatures. At room temperature, the adsorbed layer is composed of multiple silicon chlorides and hydrides. At exposure temperatures between 200 and 400° C, the surfaces are covered primarily by SiCl with some higher chlorides and unchlorinated Si also present. The specific distributions of these species are slightly different on Ge(100) and Ge(111), with greater concentrations of higher silicon chlorides on Ge(111). For exposures in the range of 500 to 600° C, pure Si is deposited onto the surfaces, likely in the form of islands. For exposures at 700° C, Si is also interdiffused into the Ge substrate. © 1995.