Study On Influencing Factors Of Polysilicon Reduction Reaction

The factors affecting the growth of polycrystalline silicon are mainly divided into two aspects in Improved SIEMENS polysilicon production process,intrinsic quality factor and external quality factor.Intrinsic q uality factors refer mainly to the quality of the reaction materials which have less impact on the cost of the reduction reaction.External quality factor such as temperature of silicon rod,Reduction furnace pressure,Composition o f gas mixture,Molar ratio of H₂ to SiHC l₃ not only affect the apparent quality of the growth of polycrystalline silicon,but also do the impact of reducing power consumption and production cost.In this paper,the theoretical analysis is carried out from the following aspects.The effects of the reaction temperature,the reaction pressure,the ratio of the reactants,the nozzle structure,the number of silicon rods in the furnace,the silicon core type,the composition of the mixture,the material type of inner wall of the furnace tubes on the reaction were investigated in detail.The comparative analysis of the experiment from the conversion of reduction,power consumption,polycrystalline silicon yield,amorphous silicon yield,and silicon rod surface quality were carried out and the optimized reaction conditions were obtained.The optimized process was proved by practical validation.The results show that our study can guide the production of polycrystalline silicon and reduce production costs.