Hydrothermal synthesis of plate-like ZnO micro-crystal films on silicon substrates

The hexangular plate-like zinc micro-crystal films were deposited on silicon (100) substrates through the vacuum evaporation method and the plate-like ZnO micro-crystal films were prepared on silicon substrates by hydrothermal process with N₂H₄·H₂O solution. The results of XRD, SEM and EDS analyses indicate that the plate-like ZnO micro-crystals with zincblende structure have a length of about 1μm and a thickness of about 100nm, which grow almost vertically to the surface of silicon substrate and randomly assemble to form a continuous film. Taking account of the morphologies of oxidation product of zinc micro-crystal films on silicon substrates at ambient, the mechanism of zinc hydroxide dehydration is suggested to explain the formation process of the plate-like ZnO micro-crystal films on silicon substrates. The photoluminescence spectrum shows that the ZnO micro-crystal film is with a strong emission at near edge band-gap and weak emissions related to defects.