The content calculation of hexagonal phase inclusions in cubic GaN films on GaAs(001) substrates grown by metalorganic chemical vapor deposition

Cubic GaN(c-GaN) films are grown on GaAs(001) substrates by metalorganic ch emical vapor deposition (MOCVD). Two GaN samples were grown with different buffer layer, the deposition time of each was 1 and 3 min, respectively. 4- circle X-ray double crystal diffraction (XRDCD) was used to study the secon dary crystallographic phases presented in the c-GaN films. The phase compos ition of the epilayers was determined by X-ray reciprocal space mapping. Th e intensities of the c-GaN(002) and h-GaN(10 (1) over bar 1) planes detecte d in the mapping were investigated by omega scans. The content of the hexag onal phase inclusions in the c-GaN films was calculated to about 1.6 and 7. 9%, respectively. The thicker buffer layer is not preferable for growing hi gh quality pure c-GaN films. (C) 2000 Elsevier Science S.A. All rights rese rved.