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ZnO is a novel Ⅱ - Ⅵ compound semiconductor material having a larger band gap at room temperature degrees (3.37eV) and a larger room temperature exciton binding energy (60meV). Difficult to be oxidized in the atmosphere, having a high thermal stability and chemical stability. It has broad application prospects in the field of (laser) of ultraviolet light-emitting diode, thin film transistors, UV detectors, dilute magnetic semiconductor gas sensor. ZnO thin film method of making a lot of, the traditional method: magnetron sputtering, chemical vapor deposition (CVD), a sol-gel method, spray pyrolysis method, a thermal oxidation method, a molecular beam epitaxy (MBE), etc., the new growth technique such as pulsed laser deposition (PLD), a metal organic chemical vapor deposition (MOCVD), atomic layer epitaxial growth law (ALE), a laser molecular beam epitaxy (LMBE) also started to be widely used. The papers by rf magnetron sputtering on glass substrates prepared pure ZnO and ZnO: Cu and ZnO: Mg films, in order to expand the range of applications of the material and as a reference for future study, we measured the structure of the thin film samples, The doping amount of other parameters, and their optical properties were studied. (1) Use of the X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscope (SEM) the morphology of the samples were characterized, and the structure of the ZnO film the stress analysis. Show: All samples emerged as a strong (002) diffraction peak, the better the c-axis preferred orientation. Of ZnO: Cu film, and with the increase in the amount of Cu Doping, the diffraction peak intensity of the film is gradually reduced, the FWHM increases, the deterioration of the degree of crystallization. When the doping amount of 2at%, the minimum film grain at this time, the degree of crystallinity is the worst. With doping amount continues to increase, the degree of crystallization of the film to improve. With the increase in the amount of Mg-doped ZnO: Mg film, the film FWHM is reduced, the degree of crystallization becomes good. When the doping amount is 16at%, the degree of crystallinity of the film is preferably the largest grain size continues to increase, as the doping amount, the crystallization degree of the film are decreased. (2) while the optical properties of the films were analyzed in the study of the photoluminescence (PL) of the sample found: ZnO: Cu films there are three emission peak, respectively, corresponding to 400nm (violet), 444nm and 484nm ( The Blu-ray). ZnO: Mg films appeared in four emission peaks corresponding to 356nm and 389nm (UV), 444nm (blue), 490 nm (blue-green). The purple peaks exist with the presence of the exciton great, and Blu-ray emission is mainly due to the transition on the shallow acceptor level formed by the electrons from the conduction band to the zinc vacancy. (3) With the increase in the amount of Cu Doping the film bandgap width E_g of attendant decrease sample optical band gap value of 3.26eV gradually reduced to 2.99eV. The experiment also found that the transmittance of the thin film also decreases with the increase in the amount of Cu Doping. ZnO: Mg with the increase in the amount of Mg-doped, the film width of the band gap E_g increases, the sample optical band gap value is gradually increased from 3.26eV to 3.81eV. The average transmittance in the visible region, which is up to 92% or more.
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