| Zinc oxide, ZnO, a wide direct-gap semiconductor, attracts as much attention as GaN in photoelectric research field. Its photoelectric characteristics were little affected by vacancies. And it has great uses in this information age. It can be used to fabricate display devices, high frequency filters, emitting diode, lasers and high-speed optical switch. Therefore, it has great uses in both civil and military fields. In order to fabricate the above-mentioned devices and realize its uses, what we should do firstly is to get high quality ZnO film. A lot of methods have been used to deposit ZnO films such as Molecular Beam Epitaxy (MBE), Metal-organic Chemical Vapor Deposition (MOCVD), Pulsed Laser Deposition (PLD), Atomic Layer Epitaxy (ALE), Sputter and Thermal Evaporation. Among them, high quality ZnO films can be obtained by MBE, MOCVD, PLD, and PLD provides high growth rate and growth efficiency, large area uniformity and different doping processes. Therefore, PLD offers the advantage of industrial production. In the thesis, we grow high quality ZnO films deposited on a -Al2O3, c-Al2O3,MgO,MgAl2O4 substrates by new PLD system and study their characteristics.The effect of deposited condition, include substrate temperatures, different substrates and annealing on the structural properties of ZnO films has been studied in considerable detail. It is found that the optimal conditions to deposit ZnO are below: the substrate temperature of 450C, the substrate of sapphire. The sample on this condition is 0.3491. The surface morphology shows a closed-packed columnar grain indicated by atomic force microscope (AFM). The films have a highly oriented growth characteristics with the c-axis perpendicular to the substrate surface. As well, the compress stress existed in (002) crystal plane are found and can be explained by the matching between film material and substrate material as well as the different thermal expand coefficient between them. Annealing can decrease and transform this compress stress to a certain extent. Photoluminescence spectra that were excited by Xe laser at room temperature showed a blue band emission with great intensity.We also prepared c-axis oriented ZnO-based diluted magnetic semiconductor Zno.85Coo.14Cuo.01O films. By measuring the magnetic hysteresis loop of films, we found the films were ferromagnetic at room temperature. The" "saturation magnetization of the films was calculated to be 0.0029emu, 0.0021emu and the coercive field (Hc) was about 495.8Oe, 1636.2Oe respectively.Zinc oxide powders are used extensively as important inorganic materials, so there is a growing demand for them in the market. However, higher and higher requirements of their microstructures such as size, shape, etc. are proposed with the continuous development of related research and application. Sol-gel method is a prospective one that may be used to prepare ultrafine zinc oxide powders on a industrial scale owing to its uncomplicated equipment and convenient operation. In this paper, the preparation process of zinc oxide powders was studied and analyzed particularly by sol-gel method. The obtained powders were also characterized appropriately.The formation of mono-phase zinc oxide was confirmed by means of XRD and IR analysis. The sizes and shapes of particles were examined by TEM. The experimental results showed that sizes of particles increased in varying degrees with the increase of heat-treating temperature; moreover the agglomeration of particles became more serious. PL spectra showed the luminescence intensity decreased with increasing the heat treatment temperature.Not only is the present work a solid base for further research on ZnO films and nanoparticles, but also an active endeavor in the application process.
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