X-RAY-DIFFRACTION METHOD FOR CHARACTERIZATION OF THIN SURFACE-LAYERS AND THIN EPITAXIAL-FILMS

A new convenient diffraction technique is proposed, which enables us to infer a depth distribution of crystalline quality ir. a thin crystal layer. When a crystal plate is laid on the side and its reflecting planes get arranged in the vertical with tilting of the surface by a given angle, x-ray diffraction from the thin surface layer can be obtained. Since glancing angles of x-ray beams are changed with turning of the crystal by an angle around the diffraction vector and thereby the x-ray penetration depth is changeable, the depth distribution can be measured. The applicability to characterization of surface damage layers of GaAs crystals and a thin InGaP epitaxial film on a GaAs substrate is demonstrated.