Growth and orientation of GaN epilayers on NdGaO/sub 3/ by hydride vapor phase epitaxy

Growth characteristics of GaN on NdGaO/sub 3/ [011] and (101) substrates by hydride vapor phase epitaxy are investigated. The epitaxial relationship is found to be GaN(0001)/NdGaO/sub 3/ [011] with GaN [10-10]//NdGaO/sub 3/ [100] for NdGaO/sub 3/ [011] and GaN(11-24)/NdGaO/sub 3/[101] with GaN[11-2-4]//NdGaO/sub 3/ [10-1] for the NdGaO/sub 3/ [101]. When the GaN is directly grown on NdGaO3/sub /substrates around 1000/spl deg/C, no deposits of GaN are obtained due to the reduction of the NdGaO3/sub s/ substrate by the presence of NH/sub 3/ at high temperature. In order to avoid the substrate reduction, low-temperature grown GaN is effective as the protective layer.