发表刊物：无机材料学报
所属单位：材料科学与工程学院
卷号：32
期号：3
页面范围：281-286
ISSN号：1000-324X
摘要：Preparation of 6N grade polycrystalline silicon materials using raw materials of industrial silicon was explored by medium melting, directional solidification and electron beam melting. The contents of impurities B and P in the samples are both lower than 0.20 ppmw, while the total content of metal impurity (TM) is less than 0.23 ppmw. Dur-ing the process of removing B by medium melting, a large proportion of Al and Ca is simultaneously removed through the redox reaction. During the process of electron beam melting, volatile impurities including P, Al and Ca are fur-ther effectively removed by using saturated vapor pressure. Meanwhile, other metal impurities are removed by de-creasing beam power, which induces the occurrence of directional solidification. Coupling of metallurgical methods reduces the purification process of polycrystalline silicon, and provides the technical support for continuous and large-scale production.
备注：新增回溯数据