WURTZITE GAN EPITAXIAL-GROWTH ON A SI(001) SUBSTRATE USING GAMMA-AL2O3 AS AN INTERMEDIATE LAYER

Wurtzite GaN films have been grown on (001) Si substrates using gamma- Al2O3 as an intermediate layer by low pressure (similar to 76 Torr) me talorganic chemical vapor deposition. Reflection high energy electron diffraction and double crystal x-ray diffraction measurements revealed that the thin gamma-Al2O3 layer of ''compliant'' character was an eff ective intermediate layer for the GaN film grown epitaxially on Si. Th e narrowest linewidth of the x-ray rocking curve for (0002) diffractio n of the 1.3 mu m GaN sample was 54 arcmin. The orientation relationsh ip of GaN/gamma-Al2O3/Si was (0001) GaN parallel to(001) gamma-Al2O3 p arallel to(001) Si, [11-20] GaN parallel to[110] gamma-Al2O3 parallel to[110] Si. The photoluminescence measurement for GaN at room temperat ure exhibited a near band-edge peak of 365 nm (3.4 eV). (C) 1998 Ameri can Institute of Physics.