Papers by Author: Peng Xun Yan

Abstract: Zinc oxide (ZnO) and Zirconium (Zr) doped ZnO nano films have been successfully fabricated by radio frequency (RF) magnetic sputtering. The crystal structure and morphology were investigated by X-ray Diffraction (XRD), Field Emission-Scanning Electron Microscope (FE-SEM) and Transmission Electron Microscope (TEM). As the doped Zr content increases, ZnO nano films show various morphologies. The optical band gap of pure ZnO films increases from 3.27 eV to 3.53 eV with Zr concentration increasing to 9.66 at.%. After annealing, the polycrystalline structure of ZnO changes a little and the energy gap decreases. In addition, the clean and lower doped ZnO films show much lower transmittance.

Abstract: Both ZnO nanocomb and nanotetrapod structures have been synthesized via a simple chemical vapor deposition process in a horizontal tube furnace. The morphology of the products is affected by the distance between the source material and the deposition substrate. The formation of nanocombs has been attributed to the self-catalysis effect of polar surface. The octahedral multiple-twin model is responsible for the formation of tetrapods and tripod-like arms at the end of nanowires. The evolutive process of them has been given out in detail and the results provided valuable models in understanding crystal growth mechanisms in nanometer building-blocks and to further grow net nanostructures. And their photoluminescence properties also have been discussed.

Abstract: Zinc oxide (ZnO) and Dysprosium (Dy) doped ZnO nano films have been successfully prepared by radio frequency (RF) magnetron sputter. Then the crystal structure, morphology and optical of the films were investigated. All the samples have a preferred orientation with the (0 0 2) orientation perpendicular to the substrates. The surface morphology of the films changes greatly with the increasing of doping content. Agglomeration appears when the doping content is excess, which may result from the recrystallization of the small crystalline grain. The average transmittance in the visible range all exceeds 80% for the different doping content films and the band gap increases from 3.26eV to 3.34eV.