Method for preparing large-sized silicon ingot for solar cell

Abstract

The invention discloses a method for preparing a large-sized silicon ingot for a solar cell, and relates to the technical field of a method for polycrystalline silicon or single crystal silicon ingotcasting. The method uses a silicon single crystal rod clamping tool made of molybdenum to arrange silicon single crystal rods in a composite crucible of a molybdenum crucible and a ceramic ring in a same crystal orientation array, and then a cosolvent (high-purity copper powder or a fine piece of copper block) is added to the molybdenum crucible; a melt is made to be subjected to temperature gradient solidification by multi-temperature zones and plasma melting. Through a plasma electrode, on the one hand, the interfacial stability of the solidification of the silicon melt is improved, on the other hand, the supercooling degree of the components is reduced by the volatilization of copper. Finally, the single crystal block array is rapidly solidified into a monolithic quasi-single crystal, the characteristics of high gradient solidification and high-speed solidification are used and finally the silicon ingot is taken out by breaking the ceramic ring. The method for preparing the large-sized silicon ingot for the solar cell has the characteristics of high crystallization efficiency.

Description

technical field [0001] The invention relates to the technical field of methods for casting polycrystalline silicon or single crystal silicon ingots, in particular to a method for preparing large-sized silicon ingots for solar cells. Background technique [0002] Silicon is an important semiconductor material and one of the basic materials for making chips and integrated circuits. With the depletion of non-renewable energy sources such as petroleum, the whole world pays more and more attention to the application of solar energy. Since silicon is abundant in the earth's crust, silicon is currently considered the most ideal solar energy conversion material, and silicon-based solar cells are considered one of the best ways to solve energy problems. With the development of the photovoltaic industry, the demand for high-quality polysilicon crystalline silicon is increasing. The larger the size of the substrate, the lower the cost of making solar cells, but the difficulty of maki...

AI Technical Summary

Problems solved by technology

The larger the size of the substrate, the lower the cost of making solar cells, but the difficulty of making crystals increases

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