An edge etching method for improving the electrical performance of crystalline silicon solar cells

Abstract

The invention discloses an edge etching method for improving the electrical property of crystalline silicon solar cells. On the premise of not adding the processing step of mass production of the crystalline silicon solar cells, damage to the edges of silicon wafers in the etching process is effectively reduced.

Description

technical field [0001] The invention relates to the field of manufacturing crystalline silicon solar cells, in particular to an edge etching method capable of improving the electrical performance of crystalline silicon solar cells. Background technique [0002] At present, most large-scale mass production manufacturers at home and abroad still widely use traditional methods such as texturing, diffusion, edge etching, coating, and printing for the manufacture of crystalline silicon solar cells. Among them, the edge etching mainly adopts the following methods in the mass production process: Two methods, one is to use plasma for dry etching, and then use hydrofluoric acid to clean the phosphosilicate glass, and the second is to use mixed acid solution for wet etching. The effect requires the use of high-power RF power, but it is easy to cause damage to the edge of the silicon wafer during etching. The latter uses a mixed acid to etch the edge of the silicon wafer, which can eff...

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Problems solved by technology

[0002] At present, most large-scale mass production manufacturers at home and abroad still widely use traditional methods such as texturing, diffusion, edge etching, coating, and printing for the manufacture of crystalline silicon solar cells. Among them, the edge etching mainly adopts the following methods in the mass production process: Two methods, one is to use plasma for dry etching, and then use hydrofluoric acid to clean the phosphosilicate glass, and the second is to use mixed acid solution for wet etching. The effect requires the use of high-power RF power, but it is easy to cause damage to the edge of the silicon wafer during etching. The latter uses a mixed acid to etch the edge of the silicon wafer, which can effectively reduce the damage to the edge of the silicon wafer during the etching process , can also remove the diffusion layer on the back of the silicon wafer, but because the mixed acid usually used in acid etching is a mixture of nitric acid and hydrofluoric acid, this acid solution system is very easy to form porous silicon on the surface of the silicon wafer, which is not conducive to enlarging the silicon wafer. The reflectivity on the back is also not conducive to reducing the recombination on the back of the silicon wafer, which in turn affects the electrical properties of crystalline silicon solar cells

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