Polysilicon reducing furnace with multiple gas outlets on chassis

Abstract

The invention discloses a polysilicon reducing furnace with multiple gas outlets on the chassis. The polysilicon reducing furnace comprises a furnace body, a jacket, a chassis, a support, a plurality of pairs of electrodes, a silicon core, a mixed gas inlet pipe and inlet nozzle, a plurality of gas outlets and gas outlet pipes, a cooling system, an observation sight glass and the like. The polysilicon reducing furnace is characterized in that a plurality of gas outlets are arranged on the chassis of the reducing furnace, the gas outlets are uniformly distributed on the chassis in circles. As a plurality of gas outlets are arranged on the chassis in the furnace, the inner space of the furnace can be full of the gas moving back to the bottom and the tail gas obtained by the reaction, the gases can flow downward uniformly to the gas outlets on the chassis to be discharged and the gases can be distributed uniformly in the entire furnace. The advantage of uniform gas distribution in the furnace can be more remarkable when the chassis of the high-capacity reducing furnace is provided with a plurality of gas outlets. As the gas in the furnace is distributed uniformly, the deposition rate of silicon on the surface of the silicon rod can be accelerated, the thickness of the obtained rod-shaped polysilicon product is uniform from top to bottom and both quality and yield of the product can be increased.

Description

technical field [0001] The invention relates to a polysilicon production equipment, in particular to a polysilicon reduction furnace. Background technique [0002] At present, polysilicon production enterprises mainly adopt the improved Siemens method. The production process of this method is to use chlorine and hydrogen to synthesize hydrogen chloride (or purchased hydrogen chloride), hydrogen chloride and metallurgical silicon powder to synthesize trichlorosilane at a certain temperature, and the trichlorosilane after separation and rectification purification enters the reduction furnace and is reduced by hydrogen , to produce high-purity polysilicon by chemical vapor deposition reaction. The process includes five main links: synthesis of trichlorosilane, rectification and purification of trichlorosilane, hydrogen reduction of trichlorosilane, recovery of tail gas and hydrogenation separation of silicon tetrachloride. [0003] Among them, the hydrogen reduction of trichl...

AI Technical Summary

Problems solved by technology

The main problems in the existing technology are: since the chassis is only provided with one gas outlet, the flow of the reentrant downward gas and the tail gas generated by the reaction is uneven, resulting in uneven distribution of the gas flow field in the entire furnace

Uneven distribution of gas in the furnace will affect the deposition rate of polysilicon, and also lead to uneven thickness of the generated polysilicon rods, affecting product quality

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