OPTICAL-PROPERTIES OF GAN GROWN OVER SIO2 ON SIC SUBSTRATES BY MOLECULAR-BEAM EPITAXY

We investigate the optical properties of GaN grown over SiO2 on SiC su bstrates by electron cyclotron resonance assisted molecular beam epita xy. The photoluminescence spectra and refractive index of GaN were com pared for GaN/SiO2/SiC and GaN/SiC. Strong band-edge luminescence was observed at 3.40 eV from the GaN on both SiO2/SiC and on SiC. No defec t-related yellow luminescence was observed. The refractive index of Ga N at 1.96 eV (632.8 nm) was measured at 2.22 and 2.24 for GaN/SiO2/SiC and GaN/SiC, respectively. (C) 1998 American Institute of Physics.