| ZnO is a kind of semiconductor with piezoelectricity and photoelectricity character, and it is hexahedron, so it is suitable for the grown of membrane with high quality. In normal situation it is a typical semiconductor with direct band gap, which hold density 5.67g/cm3, crystal lattice constant a=0.325nm, c=0.51nm. In the crystal configuration every Zn atom and four O atoms form a tetrahedron.ZnO thin film is a kind of material with wide use, which characteristics vary due to the dissimilarity of components and production condition. Since a period of time, the research on ZnO thin film has been focused on the piezoelectricity, transparent conductance, photoelectric- ity, gas sensitivity, pressure sensitivity, and atc. It has a wide variety of applications such as transparent conductors, luminescence diode, window materials for solar cells, optical wave-guide, materials for monochrome field emission display, piezoelectric transducers in the GHz range, surface acoustic wave devices, micro-sensors and micro-actuators, and low-voltage varistors. With the improvement of production technique, P type adulteration and PN kink, making ultraviolet radiation semiconductor laser and optically pumped UV lasing of ZnO thin film become new edge fields.The different uses of ZnO thin film have different requirements on crystal tropism, surface plane, conductance, piezoelectricity, optics characters and gas sensitivity which depend on the technical parameters of manufacture. Now in order to improve and control the characters of material, a lot of production techniques appears which includes magnetro-sputtering, pulsed laser deposition, spray pyrolysis, chemical vapor deposition , sol-gel processing, molecular beam epitaxy, double hydronium spatter deposition, Zn membrane oxidation, and so on. Magneto-sputtering is the practical way in our country.This thesis focused on the luminescence characters of ZnO thin films with two different substrates.We measure the absorbable spectrum of two samples, and they have strong free exciton absorbing peak at 377nm and 374nm correspond to forbidden bandgaps of E g≈3.30eVand E g≈3.32eVrespectively. The data are very close to the previously reported[63,64](3.37eV), which confirm the high quality of our samples. According to the peak position we set the laser wavelangth at 355nm, and measured the fluorescence spectra, shown in figure1 and figure2. The wavelengths of the luminescent peaks of the two samples are 393nm and 396nm respectively. The samples showed high absorb ability and the strong ultraviolet emission, which indicates that there are few defects in our ZnO thin films, and the quality of the films are very good. The relationship between the intensity of fluorescence peak and the intensity of laser is shown in figure3 and figure4. The pumping laser power dependence of ultraviolet radiation peak values are shown in figure3 and figure4. It has been found that the centro-wavelength of the ultraviolet radiation peak keeps constant and the intensity of ultraviolet radiation increases as the intensities of the pumping light, which means that the ultraviolet radiation peak comes from the radiation combination of band-side free exciton.In order to investigate the excitation of radiation, we measured the excitation spectra of the two samples with monitoring wavelengths of 437nm and 466nm, shown in figure5 and figure6. The figures show that the best pumping wavelengths are 395nm and 370nm. In order to explain the crystallization characteristics of the samples,we have measured the Raman spectrum of the samples under the room temperature, shown in figure7 and figure8. In figure7, the peak at 437cm-1 is the characteristic Raman peak of ZnO crystal, this peak shows the crystalline state of ZnO thin film on quartz is fine. The peak at 431cm-1 is the characteristic Raman peak of ZnO thin film on sapphire in figure8 and has a shift to the low frequency. This indicates that there is tension stress in the ZnO thin film on sapphire. Other peaks in figure7 and figure8 come from substrates. In conclusion, we have investigated luminescent characteristics of ZnO thin films with two kind different substrates,through our work we have seen that a lot of work should be done in the future, since more wide uses and marketing prospects of ZnO thin film will be found.
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