Material Characterization of Epitaxial GaAs and Ge Films on (100) Si Substrates

Abstract

ABSTRACTWe report some results on the chemical, structural and electrical characterization of Ge and GaAs films, grown on Si (100) substrates by electron-beam evaporation and MOCVD, respectively. Good quality Ge films have been obtained at 700°C substrate temperature at a growth rate of 5 nm/sec in 5 × 10−7 torr. Similarly, good GaAs films were obtained at 650°C and at 0.3 nm/sec. RBS data for GaAs films (1.1 μm) show Xmin approaching 3.5%, and Ge films (1.5 μm) around 3.6%. Photoluminescence of the same films show peaks around 852 nm with FWHM of 14 meV. Cross-sectional TEM and etching show a near-exponential decrease in defect density away from the Ge/Si interface. Detailed characterization results of the S-R, I-V, C-V, and X-ray studies are also described.