The Research Of Polycrystalline Silicon Ingot Casting And Simulation Of Thermal Field

With the growing consumption of conventional energy sources and the damage to the environment which caused has become more and more serious, so,it makes human had to seek a renewable energy for make human society can sustainablily develop. Clean, safe, abundant solar energy become the focus of research. At present, the solar cell battery mainly divided into three: monocrystalline cells,polycrystalline silicon and thin-film solar battery.Compared to the high cost and high technical requirements of monocrystalline cells and the difficulties in technology stability and economies of scale of thin-film- solar, polycrystalline silicon become the main raw materials in solar cells. It is mature that polycrystalline silicon ingot casting technology, at present, the world's main research targets focused on reduce cost, improve quality and yield as well as the studies above more large size. To improve silicon ingots quality, output and lower costs need to bubble of polysilicon process in-depth study, with constant studies to optimize polycrystalline silicon ingot casting process. However, because of the risk, long life cycle and expenses in polycrystalline silicon ingot casting, so, do the simulation is an effective method for polycrystalline silicon ingot casting, it plays a guiding roleThe main works in this paper were:1. Introduces the development and research of industry of solar energy photovoltaic industry, and the preparation methods of silicon ingot casting;2. Do research on the influence of the defect, impurities and impurity to polysilicon Minority carrier life, and then adopting microWave attenuation instrument (μ- PCD)to detect Minority carrier life of polycrystalline silicon ingots;3. The key work in this paper is to research the thermal field of polysilicon ingot casting, which is vital to the growth of polycrystalline silicon crystals. The crystal-cooling process, the shape of solid-liquid interface, the thermal stress distribution of crystal and so forth are all determinated by the thermal field and temperature gradient during crystal growth process. Therefore, the thesis put the emphasis on the thermal field's study of the polycrystalline silicon ingot production furnace. So, after using the software of FLUENT to analog temperature field of polycrystalline silicon ingot casting process, the result of the temperature field distribution image has been got. It is tally with actual situation when compared with actual situation of polycrystalline silicon ingot casting process which has an important significance in sustainable development of photovoltaic industry.