Electronic-grade high-purity polysilicon reduction starting equipment and starting method

Abstract

The invention provides electronic-grade high-purity polysilicon reduction starting equipment and starting method. The equipment comprises a microwave generation device and a reduction device, whereinthe reduction device comprises a first power supply assembly and at least one reduction furnace; a furnace body of the reduction furnace comprises a microwave feed inlet provided with at least one seal cover, and the seal cover and the furnace body form a sealed cavity; microwaves generated by the microwave generation device penetrate through the seal cover to enter the furnace body to heat heating elements in the furnace body, so that the temperature of the heating elements reaches the starting temperature; the first power supply assembly is used for low-voltage power supply to the heating elements after the temperature of the heating elements reaches the starting temperature, accordingly, polysilicon is deposited on the surfaces of the heating elements, potential safety hazard brought byhigh-voltage power supply is avoided, and safe operation of the equipment is guaranteed; the microwave generation device is located outside the reduction furnace, the microwaves enter the sealed furnace body after penetrating through the seal cover, therefore, no impurities are introduced, and the high purity of generated polysilicon is guaranteed.

Description

technical field [0001] The invention relates to the technical field of polysilicon production, and more specifically, to an electronic-grade high-purity polysilicon reduction start-up device and a start-up method. Background technique [0002] As the main raw material of the photovoltaic industry and the semiconductor industry, polysilicon has an increasing industrial demand and higher requirements on its quality. At present, the method of producing polysilicon is mainly the hydrogen reduction method. It uses the purified trichlorosilane and purified hydrogen as raw materials and feeds them into the reduction furnace. Under high temperature and pressurized environment, the two undergo a chemical reaction to form polysilicon, which is deposited on the heating element in the reduction furnace. [0003] In the prior art, when polysilicon is produced using a reduction furnace, the silicon core is used as a heating element. However, since silicon has poor conductivity and high...

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Problems solved by technology

[0004] However, the above two start-up methods have defects: in the first scheme, during the heating process, the material of the electric radiation heater itself or the accompanying impurities will volatilize into the reduction furnace, which will affect the purity of the polysilicon produced. Moreover, polysilicon will adhere to the heater, which affects the service life of the heater; in the second scheme, high-purity polysilicon needs to be used to prepare high-purity polysilicon cores, and the higher the purity of the silicon core, the required breakdown voltage The higher the voltage is, the higher the voltage is, the discharge and ignition phenomenon will easily occur in the reduction furnace, and the higher voltage will break down the insulating part outside the electrode at the bottom of the silicon core, which will affect the safe operation of the equipment.

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