Polysilicon ingot and manufacturing method of same

Abstract

The invention discloses a polysilicon ingot and a manufacturing method of the polysilicon ingot. The manufacturing method comprises the steps of directly placing a silicon material into a crucible of a polycrystal ingot furnace; heating the crucible, thus completely melting the silicon material; cooling the crucible, thus allowing the molten silicon material to begin crystallizing at the bottom of the crucible; when the growing height of the polysilicon ingot is 20mm-60mm including the end point values, controlling the thermal field in the polycrystal ingot furnace, melting back the grown polysilicon ingot, and maintaining the solid state of the polysilicon ingot at the bottom of the crucible during the melting-back process; and cooling the crucible until the growth of the polysilicon ingot is finished. According to the embodiment of the invention, the polysilicon ingot of the early growth stage is melted back, therefore the dislocation defect of the polysilicon ingot is reduced, the impurity dephlegmation during the growth process is enhanced, the quality of the polysilicon ingot product is improved and the dislocation density magnitude order of the polysilicon ingot manufactured by the method is below 10<5>.

Description

technical field [0001] The invention relates to the technical field of solar cells, more specifically, to a polycrystalline silicon ingot and a manufacturing method thereof. Background technique [0002] A solar cell, also known as a photovoltaic cell, is a semiconductor device that converts the sun's light energy directly into electrical energy. Because it is a green product, does not cause environmental pollution, and is a renewable resource, solar cells are a new energy source with broad development prospects in today's energy shortage situation. [0003] At present, international solar cells are distinguished by materials, mainly including monocrystalline silicon, polycrystalline silicon, ribbon silicon, and thin film materials (including microcrystalline silicon-based thin films, compound-based thin films and dye thin films). Polycrystalline silicon solar cells are a new generation of solar cells that have the advantages of high conversion efficiency and long life of m...

AI Technical Summary

Problems solved by technology

[0009] However, in the actual production process, it was found that the polycrystalline silicon ingot produced by the above growth process has many defects and poor quality, which restricts the conversion efficiency of the solar cell produced by it.

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