Optical and structural properties of ZnO thin films grown on various substrates by metalorganic chemical vapor deposition

We investigated the optical and structural properties of ZnO thin films grown under the same growth condition by metalorganic chemical vapor deposition (MOCVD) on various substrates such as p-Si, n-GaN, c-sapphire, a-sapphire, glass, and ITO glass. The thickness and surface roughness of the ZnO films increased with increasing lattice mismatch between the film and substrate. The ZnO films on c-sapphire showed a higher carrier concentration and conductivity than the ZnO thin films on a-sapphire and glass. In addition, the intensity of the near band-edge emission and transmittance increased with decreasing lattice mismatch between the film and substrate.