Method for manufacturing polysilicon

摘要

The present invention relates to a method for manufacturing polysilicon. According to the present invention, meltdown can be prevented during the growth of silicon rod, and a polycrystalline silicon rod having a larger diameter can be shortly manufactured with a minimal consumption of energy.

主权项

1. A method for manufacturing polysilicon, comprising the steps of:
reacting a raw material gas pre-heated to 50 to 500° C. containing dichlorosilane and trichlorosilane with hydrogen (H2) gas to deposit polycrystalline silicon on a silicon rod in a reactor provided with the silicon rod, and adjusting a molar ratio of dichlorosilane to trichlorosilane contained in the raw material gas according to the reaction progress during the deposition step of polycrystalline silicon; wherein a molar ratio of hydrogen (H2) gas to the raw material gas is 1:1 to 1:40; wherein the surface temperature of the silicon rod is maintained at 1000 to 1200° C.; wherein the deposition step is performed to have the molar ratio of dichlorosilane to trichlorosilane contained in the raw material gas of 20 to 65 mol % until the process of the following Formula is progressed to any point of 20 to 50%; and 2 to 8 mol % until the reaction is terminated since the above point:
Progress rate of process (%)={(DT−D0)/(DE−D0)}×100  [Formula] wherein D0 is a diameter of silicon rod before reaction, DE is a diameter of silicon rod after termination of reaction, and DT is a diameter of silicon rod at any point of reaction (D0≦DT≦DE).