Charging method for polycrystalline silicon ingot casting process

Abstract

The present application discloses a charging method for polysilicon ingot casting process, which includes: after laying the seed crystal of the granular material, laying silicon blocks at the four corners of the crucible, the silicon blocks are used to block the melting after melting. erosion of the seed crystal by the liquid, wherein a first preset distance is maintained between the silicon block and the inner surface of the crucible; and silicon material is added. The above-mentioned charging method for the polysilicon ingot casting process provided by the present application can avoid too much melting of the corner and edge seed crystals, avoid crystal grain degradation, and improve the conversion efficiency of silicon wafers.

Description

technical field [0001] The invention belongs to the technical field of photovoltaic equipment, in particular to a charging method for polysilicon ingot casting process. Background technique [0002] In the polysilicon ingot casting process, the seed crystal needs to be effectively protected. The methods of protecting the seed crystal in the prior art start from the thermal field, add a layer of soft felt between the guard plate and the crucible, or add a hard felt outside the guard plate for heat insulation, and cooperate with the heat insulation cage The opening to achieve the purpose of protecting the seed crystal. [0003] However, the above-mentioned method in the prior art is relatively affected by soft felt, hard felt, thermal field structure and process. Due to the problem of thermal field structure, the silicon material at the edge will flow to the corner and edge after melting, resulting in corners Too much melting of the top and edge seeds will result in grain de...

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Problems solved by technology

[0003] However, the above-mentioned method in the prior art is relatively affected by soft felt, hard felt, thermal field structure and process. Due to the problem of thermal field structure, the silicon material at the edge will flow to the corner and edge after melting, resulting in corners Excessive melting of the top and edge seeds leads to degradation of the grains and reduces the conversion efficiency of the silicon wafer

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