Growth and orientation of GaN epilayers on NdGaO3 by hydride vapor phase epitaxy

Growth characteristics of GaN on NdGaO₃ (011) and (101) substrates by hydride vapor phase epitaxy are investigated. The epitaxial relationship is found to be GaN(0001)/NdGaO₃ (011) with GaN [10-10]//NdGaO₃ [100] for NdGaO₃ (011) and GaN(11-24)/NdGaO₃(101) with GaN[11-2-4]//NdGaO₃ [10-1] for the NdGaO₃ (101). When the GaN is directly grown on NdGaO3_{substrates around 1000°C, no deposits of GaN are obtained due to the reduction of the NdGaO3s substrate by the presence of NH3 at high temperature. In order to avoid the substrate reduction, low-temperature grown GaN is effective as the protective layer}