(1. 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，昆明 650093；
2. 昆明理工大学冶金与能源工程学院，昆明 650093；
3. 云南冶金集团总公司 技术中心，昆明650031)
摘 要: 根据相关热力学数据，首先计算并拟合得到Si-Cl-H三元系中气相Cl与H原子的摩尔比(nCl/nH)与反应达到平衡时的气相Si与Cl原子的摩尔比 (nSi/nCl)Eq的关系。为了得到合理的SiCl4 (STC)和SiHCl3 (TCS)的进料配比，详细分析TCS与STC的3种配比(nTCS/nSTC分别为1/4、1和4)时温度、压强以及进料配比对Si沉积率的影响。结果表明：以STC和TCS的混合物为原料时，最佳温度为1400K，压强为0.1MPa。为了保证硅产率达到可工业化生产的35%以上，当原料摩尔比(nTCS/nSTC)为1/4时，原料中nCl/nH为0.055；当原料摩尔比(nTCS/nSTC)为1时，原料中nCl/nH比为0.07；当原料摩尔比(nTCS/nSTC)为4时，原料中nCl/nH为0.09。随着硅原料中TCS所占比例的增大，在较高的nCl/nH下，就可以得到较高的硅产率。最后分析得到：当选定原料配比时，要得到合理的硅产率，所需要控制nCl/nH的范围；当进料中nCl/nH一定时，要得到合理的硅产率，需选择原料配比的理想范围。
关键字: 西门子法；SiHCl3；SiCl4；多晶硅；硅产率
（1. National Key Laboratory for Clean Application of Complex Non-ferrous Metal Resources,
Kunming University of Science and Technology, Kunming 650093, China;
2. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China？
3. Technology Center, Yunnan Metallurgical Group, Kunming 650031, China）
Abstract:Based on the thermodynamic data for related pure substances, the relation of (nCl/nH)Eq (i.e. the mole ratio of Si to Cl at equilibrium), and the feeding mole ratio of Cl to H (nCl/nH) was plotted in Si-Cl-H system. Then, the thermodynamics of silicon deposition process when n(TCS)/n(STC) of 1/4, 1 and 4 were studied in order to obtain the reasonable ratio of STC to TCS. The effects of temperature, pressure and feeding mole ratio of STC to TCS on silicon yield were investigated. When the mixture of STC and TCS is fed to Siemens reactor, the best conditions are obtained as following: the temperature of 1400K, the pressure of 0.1MPa. In order to maintain the higher silicon yield (higher than 35%), the nCl/nH should be 0.055 when the n(TCS)/n(STC) is 1/4，0.07 when the n(TCS)/n(STC) is 1 and 0.09 when n(TCS)/n(STC) is 4. The reasonable silicon yield can be obtain under higher nCl/nH when n(TCS)/n(STC) is higher. Finally, the range of nCl/nH is obtained to maintain the reasonable silicon yield when n(TCS)/n(STC) is a constant. The range of n(TCS)/n(STC) is also obtained to maintain the reasonable silicon yield when nCl/nH in the feed is a constant.
Key words: Siemens process; SiHCl3; SiCl4; polysilicon; silicon yield
