ASSESSMENT OF THE STRUCTURAL-PROPERTIES OF GAAS SI EPILAYERS USING X-RAY (004) AND (220) REFLECTIONS/

We improved the method previously used to determine the lattice consta nts and misorientation of GaAs/Si by recording the patterns of X-ray ( 004) and (220) reflections. The (220) reflection was measured from the (110) cross section of a GaAs/Si epilayer. The structural properties of the GaAs/Si epilayers grown by metal-organic chemical-vapor deposit ion (MOCVD) using an ultrathin a-Si buffer layer were investigated. Th e rotation angle of GaAs/Si epilayers grown by MOCVD using an a-Si buf fer layer is very small and the lattice constants of these GaAs/Si epi layers agree quite well with elastic theory.