| PtSi infrared detector, has superb advantages in the fields of infrared detector and its typical application is in the guidance area. The quantum efficiency, uniformity and reliability of PtSi infrared detector is mainly depend on the properties of PtSi/Si structure. Hereby, it is of great academic significance and application value to improve the structure of PtSi/Si so as to enhance the performance of the detector. Based on theoretical analysis of the relationship between quantum efficiency of the detector and structure of PtSi/Si, the key factors and ways to improve PtSi/Si performance were proposed in the dissertation. The satisfactory results were obtained based on numerous experiments, which were focused on the improvement of the Schottky barriers and fabrication of nano-thinckness ultra-thin PtSi films. The barrier height was reduced to 0.15ev by injecting the low energy ions in PtSi/Si interface and the ultra-thin PtSi film with thickness of 4nm was obtained for the first time in the condition of lower vacuum, and the quantum ability of infrared detector fabricated with these films was increased about three-five times.Some helpful and new results were obtained as follows:1. The relationship between the detect parameters of PtSi/Si infrared detector and the properties of the films was derived. The dependence of detecting capability on the thickness of thin film and barrier height was simulated by the Monte Carlo method. Considering superposition of incidence infrared waves, integral methods were used to obtain the optimum thickness (2~5nm) of PtSi thin films within 3-5 u m wavelength, which is the result reported for the first time.2. The thermodynamics, kinetics and mechanism of atomic diffusion each other in the formation of PtSi thin films were discussed in detail. By theoretical study and experiment verification, an important conclusion was drawn that the formation of PtSi thin films can not be explained with single growth mode. Instead, it is closely related to fabrication processes.3. The theory of uniform PtSi/Si barrier was proposed. The uniformity ofillbarrier was evaluated by final phase and continuity of thin films. The effects of fabrication technology on phases, continuity and resistance of thin films were studied experimentally.4. Based on the experimental study of phases structure and barrier height of PtlrSi thin films, the conclusion was reached that it is difficult to reduce the barrier height of PtlrSi/Si. The dependence of the barrier height variation on the critical thickness and maximum doping concentration of impurity was deduced, and the injecting In* and ET at PtSi/Si interface by low energy level was applied for the first time, and the design of adjusted layer reduced the barrier height to 0.1 5ev creatively.5. A novel technique was designed to grow ultra-thin PtSi. Based on the study of some key processes including hydrogen pre-treatment, vacuum annealing and film thickness decreasing, an uniform and continuous ultra-thin PtSi film with thickness 4nm was obtained for the first time in the condition of lower vacuum by mixed growth model and step anneal. A new model film microstructure, SiOx/PtSi/Pt2Si/Si, was obtained at last.6. The characterization techniques of ultra-thin PtSi film were investigated. A new technique was proposed that to characterize the ultra-thin phase on the single crystal substrate, the accurate signal of ultra-thin film can be obtained by spectrum of the substrate and film respective so as to eliminate the noise of substrate. Accurate parameters of phases and content of ultra-thin PtSi/Si film were obtained by XPS. ARXPS was employed to measure the uniformity, microstructure and thickness of the film. By this technique, the thickness of the film, about 4nm, was measured and the layered structure was observed for the first time. TEM was also used to observe the uniformity, continuity, thickness and the microstructure of grain growth of the films. AFM was applied to observe the surface appearance...
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