THE GROWTH AND CHARACTERIZATION OF GAN GROWN ON AN AL2O3 COATED (001)SI SUBSTRATE BY METALORGANIC VAPOR-PHASE EPITAXY

Single crystal GaN films have been grown on to an Al2O3 coated (001)Si substrate in a horizontal-type low-pressure MOVPE system. A thin Al2O 3 layer is an intermediate layer for the growth of single crystal GaN on to Si although it is only an oriented polycrystal him as shown by r eflection high electron diffraction. Moreover, the oxide was not yet c onverted to a fully single crystal film, even at the stage of high tem perature for the GaN overlayer as studied by transmission electron mic roscopy. Double crystal X-ray diffraction showed that the linewidth of (0002) peak of the X-ray rocking curve of the 1.3 mu m sample was 54 arcmin and the films had heavy mosaic structures. A near band edge pea king at 3.4 eV at room temperature was observed by photoluminescence s pectroscopy. (C) 1998 Elsevier Science B.V. All rights reserved.