Homoepitaxial growth of ZnO films on ZnO (112¯0) substrates

Homoepitaxial growth of ZnO (112¯0) films was achieved on single crystal ZnO (112¯0) substrates by metal-organic chemical vapor deposition. The full width at half-maximum of grazing incidence diffraction measurement of film with thickness of 0.95 μm was smaller than that of a single crystal ZnO substrate. The surface roughness was increased from 1.7 to 37.8 nm with increase in thickness from 0.16 to 0.95 μm. In the room temperature photoluminescence spectrum of a homoepitaxial film with thickness of 0.95 μm, the intensity of green emission due to intrinsic defects was weak and the band-edge emission due to free exciton emission was dominantly observed at 3.284 eV.