Based On Slow Positron Beam And The Applications Of Preparation SiO₂ Film

There are the following characteristics with the current development of ordered mesoporous materials: (1) pore structure with rules; (2) narrow pore size distribution, and there could be adjusted between 2 and 50 nm; (3) large surface area; ( 4) has good thermal stability; (5) particles with a variety of shape. There are used in macromolecular catalysis, adsorption and separation, sensors, micro-devices and light, and electromagnetic functional materials since the first synthesis in 1992. Therefore, There are having been aroused international physics, chemistry and materials of high academic attention and been the rapid development of interdisciplinary research focus. Although the silica of preparation has been large-scale development, it is becoming more and more in the market demand for various devices, different silica structures can change the device performance,you can make it unprecedented expansion prospects by different means to change Dioxide silicon structure. Preparation and study are one of the keys, so the preparation of a new method is particularly important with the rapid development of the semiconductorI have been debugging, maintenance Slow Positron Beam Application which is based on 22Na source by our team designed and built and also to run for users, since joined the Institute of High Energy Physics positron group in 2008.We carried out more extensively involved in the applied research,and also carried out and properties of silicon dioxide film,which based on the advantages of this experimental approach in the Application of Slow Positron Beam, This paper will introduce the two parts of preparation and characterization of silica dioxide thin films and also debugging and measurement analysis of the Application of Slow Positron Beam.The silicon dioxide film was prepared by several common methods, but also prepared by Electro-assisted Self-assembly and compared these methods , Electro-assisted Self-assembly is a viable method of preparation of SiO₂ thin films, This study focuses on the structure of prepared the SiO₂ films by different methods and the method of preparation of thin films were discussed. The synthesis and characterization of mesoporous SiO₂ film were introduced in this thesis. The microstructure and performances of ordered mesoporous SiO₂ film fabricated by sol-gel method were investigated, and the film formation mechanism was discussed. According to the reported Electro-assisted Self-assembly method, we successfully prepared a series of mesoporous SiO₂ film. With changing of the reactant ratio, film preparing method, deposit times of sol and film, annealing condition, the influences of the template quality, pH value, deposit times of the sol and film, annealing temperature and heat preservation time on porous structure and film qualities of SiO₂ film were studied. The pore structure and the crystalline category of SiO₂ film were identified with SEM, XRD, and positron annihilation technique.Positron spectroscopy applications is extremely important in materials science,it has become an important the nuclear analysis methods of material micro structure. based on the our laboratory spectroscopy devices and positron spectroscopy techniques, using of high energy physics designe and build of 22Na slow positron beam equipment to carried out involving the wider field of applied research and slow positron beam devices debugging and measurement.