多晶硅还原炉气相平衡计算与分析

Discussion on the VaporPhase Equilibrium in the Siemens Bell-jar Reactor

基于Gibbs自由能最小原理,对多晶硅还原炉内气相平衡进行了计算,系统地分析了不同温度、压力和氢摩尔配比条件下SiHCl3的转化率,以及还原尾气中SiHCl3、SiH2Cl2、SiCl4、H2和HCl等组份的平衡情况,包括流量和组成浓度等。计算结果与实际情况较吻合,可以为改良西门子工艺的物料平衡模型提供依据,也可在还原炉实际运行过程,通过尾气分析检测数据与计算数据对照,分析炉内的工艺条件状况,及时做出调整和优化。

Based on the minimized Gibbs energy principle of a close system, in which the Siemens technology uses the hydrogen reduction of SiHCl3 to produce bulk polysilicon, the reactions are analyzed. The effect of efficient conversion of SiHCl3 to Si on the yields and Equilibrium concentration of SiH2Cl2 .SiCl4 is calculated. At the same time, the effect of Temperature, the Ratio of H2 in the feed and Pressure on the vent gas components a investigated.