电子级多晶硅循环氢气深冷分离除杂技术研究

Cryogenic Separation Purification Technology of Electron Grade Polycrystalline Silicon Circulating Hydrogen

通过分析多晶硅还原炉尾气回收装置循环氢气中杂质的种类、来源、去除工艺,确定采取循环氢气深冷分离除杂技术解决磷化氢、砷化氢在氢气循环过程中的累积趋势,可以有效分离循环氢气中70%磷化氢和95%砷化氢,保证还原炉化学气相沉积过程中循环氢气的纯度。

Through the analyses of types,sources,and removal process of impurities in the circulating hydrogen in polycrystalline silicon reduction furnace tail gas recovery unit,it is determined that the circulating hydrogen cryogenic separation purification technology is adopted to solve the problem of accumulation trend of phosphine and hydrogen arsenide in the process of hydrogen circulation.It is revealed that 70%phosphine and 95%hydrogen arsenide can be effectively separated from the circulating hydrogen,which can ensure the purity of hydrogen gas vapor deposition process.