Scanning tunneling microscopy study of cleaning procedures for SiGe(001) surfaces

Ultra-high vacuum scanning tunneling microscopy and depth profiling X-ray photoelectron spectroscopy were used to evaluate two methods for cleaning Si 1− x Ge x (001) films using ex-situ surface oxidation followed by in-situ oxide desorption at temperatures ≤ 1025°C. Dry ultra-violet ozone cleaning was found to be fast, simple, and highly effective for cleaning Si 1− x Ge x (001) surfaces with a wide range of Ge content as well as standard Si(001) surfaces, consistently yielding lower surface particulate densities than a standard wet chemical cleaning technique.