真空定向凝固去除硅中杂质铝的研究  

Removal of Aluminum Impurities from Silicon by Vacuum Directional Solidification

作　　者：郑达敏[1,2] 魏奎先[3,2] 马文会[1,4] 戴永年[3,4] 

机构地区：[1]昆明理工大学冶金与能源工程学院 [2]云南省高校硅冶金与硅材料工程研究中心 [3]昆明理工大学真空冶金国家工程实验室 [4]昆明理工大学省部共建复杂有色金属资源清洁利用国家重点实验室

出　　处：《特种铸造及有色合金》2015年第4期345-347,共3页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金重点资助项目(U1137601);国家自然科学基金资助项目(61404063);国家科技支撑计划资助项目(2011BAE03B01);云南省自然科学基金资助项目(2012FB125)

摘　　要：Al是硅中的主要杂质元素之一,通过真空定向凝固去除硅中的Al,在工业化提纯多晶硅中得到广泛应用。采用纯度为99.98%、铝含量为1.54×10-6的硅为原料,在500kg铸锭炉内进行提纯试验。结果表明,杂质Al的去除效果明显,Al的含量最低可以降低到2.8×10-8,去除率达98.2%。通过对过程分析后发现,在采用铸锭炉进行提纯试验的过程中,杂质Al的去除主要是通过定向凝固提纯过程中的分凝与真空挥发共同作用完成的。Aluminum is one of the main impurity elements in silicon.The method of removing aluminum contained in silicon by vacuum directional solidification has been widely applied for industrial polycrystalline silicon purification.The purification experiment was conducted in a 500 kg ingot furnace used in industrial production with the raw material of silicon whose purity and aluminum content were 99.98%and 1.54×10-6,respectively.The experimental results demonstrate that the aluminum removal effect exhibits obvious,where the aluminum content can be reduced to a lowest value of 2.8×10-8,and a removal efficiency of 98.2% can be reached.After analyzing the process of aluminum removal,it is considered that in the process of purification experiment by employing ingot furnace,the removal of aluminum impurity is mainly completed under the co-action of dephlegmation mechanism in the process of directional solidification purification and vacuum volatilization mechanism

关 键 词：真空定向凝固 铸锭炉 提纯 杂质铝 

分 类 号：TQ127.2[化学工程—无机化工]