| With the rapid development of tactical and strategic laser weapons, the research in anti-laser blinding technology for 3~5μm and 8~12μm infrared detector used in missile guidance has become more and more important. The vanadium oxide thin film is suitable to laser protection for the nearest room-temperature phase-changing temperature and the sharp difference in reflectivity after phase change. In this dissertation, the mechanism of phase change and the theoretical calculation for vanadium oxide thin films are investigated, and contrasts in the optical characteristics after phase change and the phase change temperature's dependence on component are also studied. The vanadium oxide thin films are prepared on zinc selenide by DC magnet sputtering method. The X-ray photoelectron spectroscopy (XPS) test and data fit are performed and the components control in the films is realized by annealing. The experimental contrasts in optical characteristics after phase change demonstrate that our films can meet the demand. The components controlling technology by annealing is studied, and a novel technological way of changing the phase transition temperature without doping is explored.By utilizing the Castep program package of the Material Studio simulation tool, based on local density function approximation and pseudo-potential method, optimization for the geometric structure of vanadium oxides is accomplished with the BFGS calculate way. Using the super soft pseudo-potential of reciprocal space lattice, the electronic structure (energy band and density of states), optical characteristics of crystal, and point defect's feature are calculated within the 7μm scope. Furthermore, some trends can be concluded from the extended estimation for the optical characteristics at 10.6μm by formula. We find that the low-valence (Al, Ti, Sn) doped VO2 have broader energy gaps, possibly increase the phase transition temperature from semiconductor state to metal state; while the high-valence (W, F, Mo) doped VO2 have tighter energy gaps, possibly good for the reduction in the phase transition temperature.Based on the dynamic simulation process in Castep module, the electronic structure (energy band and state density), optical characteristics of crystal and the influence of components on phase-change temperature are calculated. As a result, the energy band and state density curves, the optical parameters such as absorption coefficient, refractive index and transmittance for vanadium oxides are obtained. Furthermore, the influence of temperature in all these curves, different components in phase transition temperatures are also got.The JGP560C8 super high vacuum multi-functional magnet sputtering instrument is designed and built, consequently, the vanadium oxide thin films are prepared on germanium and zinc selenide base by DC magnet sputtering method. Using opposite spluttering technique for the base in the pre-processing room, the mal-contact problem between zinc selenide base and the film is solved, and the optimized preparation parameters are achieved. That is, the flux ratio of oxygen-to-argon is 0.11, the temperature of base is 450℃, the gas pressure when sputtering is 2.2 Pa, the spluttering current is 0.5 A, the spluttering voltage is 330 V, the spluttering power is 165 W, and the spluttering time is 180 s. Internal components are analyzed by XPS test and data fit, For investigating the annealing technique, the films are processed in the oxygen-on and absent conditions for 4 hours under the temperature of 450℃.The expected results exhibits that the films'components has been effectively changed.Based on the absorption film's eigenmatrix method, under the pretext that the corresponding transmittances are 82% and 5% for the condition before and after phase transition, the film's thickness is calculated to be 103 nm. Also the spluttering product is estimated according to the parameters of coating equipment and experienced formula, which permits quantitative illumination that the coating rate could be controlled by adjusting the working parameters in magnet sputtering. The film thickness is 125 nm measured by profile meter. Transmittances measured by the infrared spectrometer are 79.2% and 12.3% before and after phase transition. The data calculated is in well agreement with the measured data.The transmittances of VO2 at 10.6μm under different temperatures are tested by employing CO2 laser and Nicolet8700 infrared spectrometer, respectively. Thus, parameters such as changes in the optical characteristics after phase transition and the phase transition temperature are attained. From these data, it can be seen that the transmittance could be reduced from 70.8% to 11.3% after phase transition, with a phase-transition response time less than 50 ns. The function of laser on the phase transition of VO2 film is examined. As a result, sharp difference occurs in the optical characteristics after phase transition. What's more, the phase transition process exhibits good repetivity. Therefore, it can be expected that the film can play both laser protection and signal receiver roles when placed before the detector.Observation and investigation are performed in the dependence of phase transition temperature on components in the VO2, so as its influence on parameters such as heat stagnation curve and the variation amplitude in transmittance after phase transition. Certain explanation is made basically from mechanism. By controlling the components through annealing technique, a novel technological way on the changes of non-doping phase transition temperature has been explored.
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