Method and equipment for producing elementary silicon

Abstract

The invention relates to a method and equipment for producing elementary silicon. The production method comprises the contacting step of using a vaporized silicon compound or mixed gas of the vaporized silicon compound and hydrogen as silicon feed gas to contact melting elementary silicon used as silicon feed liquid, so as to reduce the silicon compound into the elementary silicon. Compared with the prior art, the invention has lower production cost, higher production efficiency and lower energy consumption, and can prepare the elementary silicon with higher purity (such as polycrystalline silicon or monocrystalline silicon).

Description

technical field [0001] The present invention relates to a production method and production equipment of simple silicon, more specifically, the present invention relates to a silicon compound that produces simple silicon (including polycrystalline silicon and single crystal silicon) by using molten simple silicon to reduce gaseous silicon compound raw materials. Single substance production methods and production equipment. Background technique [0002] At present, the production method of most simple silicon (especially polysilicon) is the improved Siemens process, which mainly uses a bell-shaped reactor and a silicon core of about 8mm connected to the electrode as the deposition substrate, and adopts a high-temperature reduction process. gaseous silicon compound raw materials (such as SiHCl 3 ) at H 2 Reductive deposition (chemical vapor deposition) in the atmosphere to generate polysilicon. [0003] The above-mentioned chemical vapor deposition process is carried out in ...

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Problems solved by technology

[0004] However, this improved Siemens production process has the following disadvantages: 1) Due to the small specific surface area of ​​silicon rod deposition, the space utilization rate in the reactor is low, the primary conversion rate of raw materials is low, and the output is limited

[0007] However, the fluidized bed process also has problems such as the deposition of silicon on the reactor wall, which reduces the internal space of the fluidized bed, and as the thickness of the inner wall changes, the uneven thermal stress on the inner wall leads to material damage, and the fluidized bed gas distributor is prone to silicon deposition. However, clogging leads to defects such as shutdown, and the primary conversion rate of the fluidized bed process still needs to be improved.

[0008] At the same time, regardless of the Siemens process or the fluidized bed process, the rod-shaped polysilicon or granular polysilicon produced must be melted into a liquid state at high temperature in the subsequent processing steps before the polysilicon ingot can be produced or the Czochralski method can be used. Monocrystalline silicon, which undoubtedly greatly increases the production complexity, production cost and energy consumption, and there is also the risk of external impurities contaminating the manufactured polysilicon ingot or single crystal silicon (secondary pollution)

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