光氯化反应选择性脱除三氯氢硅中甲基二氯硅烷

Selective removal of methyldichlorosilane from trichlorosilane via photochemical chlorination

摘要:

研究采用连续流微通道反应器，利用光氯化反应选择性脱除三氯氢硅中的甲基二氯硅烷，考察各因素对甲基二氯硅烷去除率的影响。研究结果表明，增加氯气量和光强，升高温度，减少光源波长，延长反应时间有利于甲基二氯硅烷的去除，在最优条件下，产品中甲基二氯硅烷含量小于0.05?10-6，去除率达到99.6%；反应产物中出现少量四氯化硅，是聚氯硅烷和三氯氢硅发生氯化反应生成。以此为原料使用评价炉制备的多晶硅中碳含量小于3?1015atom/cm3，达到电子一级品指标。

Abstract:

A continuous flow micro-channel reactor was used to selectively remove methyldichlorosilane from trichlorosilane by photochlorination reaction. The effect of various factors on the removal rate of methyldichlorosilane was investigated. The results show that increasing the chlorine gas and light intensity, increasing the reaction temperature, reducing the wavelength of the light source, and prolonging the reaction time are beneficial to the removal of methyldichlorosilane. Under the optimal conditions, the methyldichlorosilane content in the product is less than 0.05ppm, the removal rate reached to 99.6%. A small amount of silicon tetrachloride is found in the reaction products, which is formed by chlorination of polychlorosilane and trichlorosilane. With the improved trichlorosilane as the raw material, the carbon content of the polycrystalline silicon prepared by the evaluating furnace is less than 3?1015atoms/cm3,which meets the requirements of the first-grade electronic products.