Real Time Observation of Reflectance Anisotropy and Reflection High-Energy Electron Diffraction Intensity Oscillations During Gas-Source Molecular-Beam-Epitaxy Growth of Si and SiGe on Si(001)

Dynamic reflectance anisotropy (RA) and simultaneous reflection high-energy electron diffraction intensity measurements on the gas source molecular-beam-epitaxy growth of Si and SiGe on Si(001) are presented for the first time. The RA signal was found to oscillate at a period corresponding to bilayer growth in both material systems, and it is explained in terms of a model based on the relative domain coverages and hence the Si dimer “concentration” in the two orthogonal $〈110〉$ azimuths.