废弃多晶硅太阳电池回收高纯硅片工艺研究

论述分析了国内外晶体硅太阳电池回收技术现状,研究了太阳电池的结构及制备工艺,提出了废弃多晶硅太阳电池回收高纯硅片的工艺.依次去除铝背场/铝硅合金层/背银、氮化硅减反膜/正银、磷扩散层及金属杂质,得到高纯硅片.硅原料的回收率高达76.4％,回收的高纯硅片经检验检测,其电阻率、间隙氧浓度、代位碳含量和少子寿命均符合GB/T 29055-2012中规定的性能参数.该回收工艺路线简单,回收率高,成本低,适于产业化推广.废弃太阳电池的回收再利用不仅可以在一定程度上缓解硅原料短缺的问题,还可以减少废弃的太阳电池给环境造成负担.

Study on the Technology of Recycling High Purity Silicon Wafers From Waste Polycrystalline Silicon Solar Cells

The current situations of the crystalline silicon solar cell recycling technology both at home and abroad were discussed.The structure and preparation process of solar cells were studied,and the process route of recycling high purity silicon wafers from waste polycrystalline silicon solar cells was proposed.The aluminum back field / aluminum silicon alloy layer / back silver,silicon nitride anti-reflective film / front silver,phosphorus diffusion layer and metal impurities were removed successively to obtain the high-purity silicon.The recovery rate of the silicon material is up to 76.4％.The recycled high-purity silicon wafers were tested,and the key performance parameters such as the resistivity,interstitial oxygen content,substitutional carbon content and minority carrier life time all meet the performance parameters requirements of GB/T 29055-2012.The recycling process is simple,high-recoveryrate,low-cost and suitable for industrial promotion.Recycling of waste solar cells can alleviate the shortage of silicon material to a certain extent,and can reduce the burden of waste solar cells to the environment.