Influencing Factors Of Poly-Crystal-Silicon By Directionaly Casting Technique

Poly-crystal-silicon has gradually replaced single-crystal-silicon as the main solar cell material in the market. Currently, in order to reduce the costs and shorten the time of solidifying the poly-crystal-silicon ingots and speed up the heat dissipation of DS bottom block, most of the companies in the market have no heat preservation material. The end of the ingot is often cooled down in order to increase the ingot solidifying speed. However, the intensified competition in the poly-crystal-silicon market renders a high-quality poly-crystal-silicon become the primary goal of most companies.In order to improve the ingot furnace and technology, the thesis investigated the following two projects:reforming the thermal field structure of the furnace, reducing the heat dissipation area of the DS bottom block, the distance between the heat dissipation material of the DS bottom block and the furnace is reduced, and a high temperature at the end of the ingot is effective at decreasing the length of the head materials. We got the following conclusions:the furnace reformation effectively reduces the black shadow defects and the PL value. Raising the temperature at the end of the ingot reduces the oxygen elements and the length of the head materials.