A kind of polysilicon etchant additive and application thereof

Abstract

The invention provides a polycrystalline silicon etchant additive and an application thereof. The additive is prepared from ethylene glycol monobutyl ether, glucose, sodium lactate, vitamin C, polyethylene glycol, sodium fluorosilicate and water. The raw materials are mixed and subjected to refluxing at 120-130 DEG C for about 10 hours to obtain the additive, the additive is mixed with a base acidsolution to obtain the etchant solution. When the etchant solution is used for texturing etching of the surface of the polycrystalline silicon wafer, the generated hydrogen bubble is very small, andcan leave the interface of the silicon wafer quickly, so that the etching of the surface of the silicon wafer can be more uniform, and the thinning amount of the polycrystalline silicon wafer can be controlled within a smaller range.

Description

Technical field [0001] The invention relates to the technical field of photovoltaic material preparation, in particular to a polysilicon etching solution additive and its application. Background technique [0002] The key to large-scale utilization of solar power generation is to prepare low-cost, high-efficiency solar cells. The drawing process of monocrystalline silicon is complicated, and the cost of silicon material is relatively high; while the ingot casting process of polycrystalline silicon is simple, and the utilization rate of square ingot silicon material is high, which can significantly reduce production costs. At present, more than 98% of the silicon in the international market All photovoltaic cells are polycrystalline silicon solar cells. [0003] However, the anti-reflective effect of monocrystalline silicon texture is obviously better than that of polycrystalline silicon. Monocrystalline silicon with uniform crystal phase distribution can obtain a uniformly dense p...

AI Technical Summary

Problems solved by technology

The rod drawing process of monocrystalline silicon is complicated, and the cost of silicon material is high; while the ingot casting process of polycrystalline silicon is simple, and the utilization rate of square ingot silicon material is high, which can significantly reduce production costs. At present, more than 98% of the silicon materials in the international market Photovoltaic cells are polycrystalline silicon solar cells

[0003] However, the anti-reflection effect of the textured surface of monocrystalline silicon is significantly better than that of polycrystalline silicon. Monocrystalline silicon with uniform crystal phase distribution can obtain a uniformly distributed and dense pyramid microstructure through anisotropic alkali etching, which can achieve an average reflectance of less than 10%; while polycrystalline silicon There are grain boundaries inside, and the average reflectance of the suede surface made by acid etching method is above 20%, which affects the improvement of the overall efficiency of the battery