冶金级硅中杂质的表面吸附与去吸附除杂  

Surface Adsorption of Impurities in Metallurgical Grade Silicon and their Removal by Desorption

作　　者：颜颉颃 彭继霆[1] 周浪[1] 周潘兵[1] 杜国平[1] 苏文华 

机构地区：[1]南昌大学材料科学与工程学院／NCU-LDK太阳能研究中心,江西南昌330031 [2]江西港源硅业有限责任公司,江西丰城331100

出　　处：《南昌大学学报（理科版）》2008年第2期170-172,177,共4页Journal of Nanchang University(Natural Science)

摘　　要：对冶金级硅的物理提纯因可望成为低成本太阳能级硅生产技术而受到各国高度关注。利用硅中杂质的表面吸附偏聚,对冶金级硅粉进行酸洗去吸附除杂。并尝试在此后进行高温退火以再次造成表面扩散偏聚,然后继以二次酸洗去吸附除杂。结果表明这种技术对硅中金属杂质有一定除杂效果,可以作为进一步提纯前的预处理;高温退火后二次酸洗能够进一步降低杂质含量,但效果并不显著,难于生产应用。扩散计算表明,高温退火偏聚处理对较重金属杂质有效,而对B、P杂质则几乎没有效果。Physical refining of metallurgical grade silicon has drawn great attention worldwide for its potential of producing solar grade silicon at low cost. Based on the phenomenon of surface adsorption of impurities, pickling of metallurgical grade silicon powders has been carried out to remove the impurities. High temperature annealing of the pickled sample, followed by secondary pickling desorption, has been attempted for further refining. The results show that the technique is effective to some extent ,and can be used as a pre - treatment for further refining. The secondary pickling may further lower the impurity content, with limited effect, which is not enough to justify an application in production. An analysis based on diffusion calculation indicates that the secondary surface segregation by high temperature annealing can be effective for impurities of heavy metals, but not for B and P.

关 键 词：冶金级硅 太阳能级硅 酸洗 表面吸附 

分 类 号：TM914.4[电气工程—电力电子与电力传动]