冶金级硅料在高温处理中的金属杂质表面偏聚

摘要

实验研究了经酸洗除杂的冶金级硅粉在空气中进行高温处理以再次造成表面杂质偏聚,然后继以二次酸洗去吸附除杂的方法。结果表明这种方法因其硅粉表面形成的硅氧化物进一步提高了金属杂质表面扩散偏聚的能力,比保护气氛条件下的高温处理有更好的偏聚效果,二次酸洗后金属杂质含量进一步降低。%High temperature treatment of pickled metallurgical grade silicon in air,followed by secondary pickling,has been carried out for removing metallic impurities.The results show that this method can further improve the metallic impurities＇ capacity of surface segregation as the silicon oxides formed on the surface of silicon.Compare with high temperature treatment in the atmosphere of protective gas,this method has better segregation effect and can further lower the metallic impurity contents.