The Growth of Semi-Polar ZnO (1011) on Si (111) Substrates Using a Methanol Oxidant by Metalorganic Chemical Vapor Deposition

Semi-polar ZnO (1011) epitaxial films are demonstrated using a methanol oxidant by metalorganic chemical vapor deposition on Si (111) substrates at 500°C. X−ray φ scanning indicates that there are six kinds of in−plane domain growths, with the ZnO 1012 parallel to the Si 〈112〉 direction families. The crystallographic orientation of ZnO is supposed to be caused by surface passivation. The methanol, as a polar molecule, may be adsorbed on the Si (111) surface to form a passivation layer, which inhibits the (0001) ZnO plane deposition on the substrate surface, and as a result the ZnO (1011) plane becomes preferred. The optical properties, examined by a room−temperature photoluminescence spectrum, exhibit a strong near-band-edge emission peak at 379 nm, indicating that the (1011) ZnO film has good crystal quality. These results are significant for research into and for the applications of semi-polar ZnO films.