The Research Of Technology Of Multi-crystalline Silicon Ingot Casting And Numerical Analysis

At present, China has mastered the Czochralski method and the multi-crystalline silicon ingot casting, and ingot technology is widely used in China. Because of its high utilization rate and low-cost, ingot casting will take a very important position in raw materials technology development in the future. The conversion efficiency of multi-crystalline silicon solar cells are only slightly lower than the monocrystalline silicon solar cells. However, the sun light under the influence of position and weather, they are almost the same. As technology continues to improve, its low cost and short production cycle with higher quality will make multi-crystalline silicon solar cells become the main force of Chinese PV industry. Many PV manufacturers are using directional solidification furnace to produce multi-crystalline silicon ingot. And the size of the silicon ingot is growing larger. We need to produce multi-crystalline silicon ingot with larger grains, lower-defect and higher conversion efficiency. In addition, more and more new materials have been used in furnace. The latest quasi-crystalline silicon ingot requires precise control of the melting and stable set of the control mode. We cannot direct measure the temperature distribution of the furnace because of the temperature is very high during the casting. Numerical simulation of the process is a cost-effective method. Some studies have shown that it still need further study to help manufacture in China.This paper introduces the development of the photovoltaic industry in recent years and elaborates on the multi-crystalline silicon directional solidification technology and furnace’s research development. And utilized the finite element software simulated multi-crystalline ingot furnace since the development of using top heater, side heater and the top-side heater. The thermal fields of different heaters in casting are analyzed. The results proved in the case of large-size silicon ingots use top-side heater is an excellent choice.The study of the thermal field of the ingot process and numerical simulation has significance in guiding the improvement of the ingot casting process.