Room‐Temperature HF Vapor‐Phase Cleaning for Low‐Pressure Chemical Vapor Deposition of Epitaxial Si and SiGe Layers

Silicon dioxide films can be etched in a mixture of and vapor. This reaction can be performed at reduced pressure, which has allowed us to develop a high‐vacuum compatible etch facility. Channeling Rutherford backscattering (RBS) analysis demonstrates the feasibility of epitaxial low‐pressure chemical vapor deposition (LPCVD) of Si and layers at 600°C on Si(100) substrates that previously have been vapor‐etched in situ at room temperature. The combination of vapor‐etching, LPCVD and RBS also provides kinetic information about the deposition of Si and . For temperatures of up to 900°C the growth from is measured to follow Arrhenius‐type kinetics with an activation energy of 1.3 eV. On surfaces Si deposition is retarded relative to clean Si substrates. Over the temperature range of 600–800°C, the incorporation of Ge in Si from mixtures obeys the relationship , for gas mixtures containing up to 5% . The growth rate of alloys is found to increase linearly with the partial pressure of .