Study On The Production Process Of CUSP Magnetic Field Under The Conditions Of400mm Large Diameter Cz Silicon

Silicon is the most important semiconductor material.especially with the large area of electronic information industry and photovoltaic power generation technology promotion, demand for silicon material is very large, and at the same time, quality and size of monocry stal line silicond emands increase. In general, the impurities are the main factors that influence the performance of single crystal silicon, oxygen is one of the main impurities, therefore.control the oxygen content in single crystal silicon is an important task to obtain high-quality solar grade silicon. Compared with conventional Czochralski silicon, large diameter silicon in the production process, due to thecrucible size, loading capacity, the crucible wall and the crucible melt contact area is large, the decomposition of impurities increases; melt motion, the wall of the crucible crucible erosion intensity, the decomposition rate is high,the melt transport capacity, high oxygen content the crystal structure of the furnace body; large size, free space above the surface, the amount of SiO volatilization faster. Therefore, this study carried out the crystal controlled impurity content in the process of growth, focusing on the process of melt convection during the growth process of400mm in large diameter Czochralski silicon, improve the quality of large diameter silicon single crystal.Due to the high temperature environment of single crystal furnace to the solid/liquid interface direct observation is very difficult, and the experimental crystal will also spend a higher cost, so we use the method of numerical simulation,to simulate the quality and size of integrated silicon equivalent diameter level large diameter Czochralski silicon growth process, by optimizing the structure parameters of magnetic field the distribution of magnetic field, to find the best within the melt crystal; pot in the process of adjust ingpulling, improve melt movement, less impurities to the crystal transport; simulation based on different argon gas flow inlet velocity of the evolution process, to find the optimum argon inlet velocity range, and for the first time proposed the gas vortex and its influence the three-phase point.