Development of Directional Solidification Technology for Growth of MC-Si Ingots for Solar Cells

Multicrystalline silicon(mc-Si)has become the dominant material for solar cells.The current major solidification technologies used for production of mc-Si ingots are casting,heat exchange method(HEM),directional solidification system(DSS)and electro-magneto casting(EMC).The research and development of this field mainly focus on increasing the size of the ingot and raising the growth rate of the ingots.Improvements in thermal field design and processes have also been carried out.The complexity in the system and process of mc-Si ingot growth and high cost of the silicon feedstock push forward the role of numerical simulation in RD of the directional solidification technology for mc-Si production.A great number of such research and application appeared abroad,from which valuable technical information has been obtained.