Structural study of GaP layers on misoriented silicon (001) substrates by transverse scan analysis

Abstract

This paper examines the structural properties of gallium phosphide layers by high resolution x-ray diffraction and atomic force microscopy measurements. GaP layers are grown on misoriented and nominally exactly oriented silicon (001) substrates by metalorganic vapor phase epitaxy. Structural characterization is performed by reciprocal lattice map and transverse scan measurements of (00l)-reflections (l = 2, 4, 6). Transverse scan line profiles of GaP layers on exactly oriented and misoriented substrates are compared thoroughly and antiphase disorder related satellite peaks are observed on exactly oriented substrates. In addition, results imply that antiphase disorder is self-annihilated on misoriented substrates. The dependence of crystallographic tilt on growth temperature indicates structural coherence. Williamson-Hall-like plot of transverse scans reveals the lateral correlation length of crystalline defects of 79 nm which gives the average size of the mosaic crystallites. In addition, the mosaicity of the GaP layer is 0.042°.