Epitaxial growth of M -plane GaN on ZnO micro-rods by plasma-assisted molecular beam epitaxy

We have studied the GaN grown on ZnO micro-rods by plasma-assisted molecular beam epitaxy. From the analyses of GaN microstructure grown on non-polar M-plane ZnO surface (101̄0) by scanning transmission electron microscope, we found that the ZnGa2O4 compound was formed at the M-plane hetero-interface, which was confirmed by polarization-dependent photoluminescence. We demonstrated that the M-plane ZnO micro-rod surface can be used as an alternative substrate to grow high quality M-plane GaN epi-layers.