Properties of GaN epitaxial layer grown on (111) MgAl2O4 substrate

We investigated the optical and electrical properties of a GaN epitaxial layer grown by metal-organic vapor phase epitaxy on a (111) MgAl2O4 substrate. The results of the photoluminescence measurement, the secondary ion mass spectrometry (SIMS) measurements, the stimulated emission experiment by optical pumping in the surface emitter configuration, and the Hall measurements were reported, indicating the high quality of the epitaxial layer. We also observed stimulated emission in edge emitter configuration from a cavity fabricated by cleavage. The threshold incident power in the edge emitter configuration was about 1/5 of that in surface emitter configuration, demonstrating that the cleaved facet of the GaN on the MgAl2O4 effectively plays the role of a mirror fora laser cavity. (C) 1997 Elsevier Science Ltd.