Alcohol-free alkaline texturing solution for mono-crystalline silicon wafer, texturing method for mono-crystalline silicon wafer, solar cell and manufacturing method for solar cell

Abstract

The invention discloses an alcohol-free alkaline texturing solution for a mono-crystalline silicon wafer, a texturing method for the mono-crystalline silicon wafer, a solar cell and a manufacturing method for the solar cell. The alcohol-free alkaline texturing solution for the mono-crystalline silicon wafer comprises an alkaline solution and a texturing additive, wherein the texturing additive is an alcohol-free additive. According to the alcohol-free alkaline texturing solution, isopropanol which is harmful to human bodies and the environment adopted in the conventional alkaline texturing solution is abandoned; the corrosion depth of the surface of a silicon wafer can be controlled within the range of 5 to 7.5 mu m easily by performing surface texturing on the mono-crystalline silicon wafer obtained by performing linear cutting on a diamond by only adopting the alcohol-free alkaline texturing solution consisting of the alkaline solution and the alcohol-free additive; meanwhile, the corrosion speed is guaranteed; the anisotropy of corrosion is enhanced; pyramid structures on the surface of the silicon wafer obtained after the texturing are small and uniform in size, so that the reflectivity of the surface of the silicon wafer is reduced by about 1 percent; the light absorption capacity of the surface of the silicon wafer is increased; the conversion efficiency of the solar cell is improved.

Description

technical field [0001] The invention relates to the technical field of solar cells, in particular to an alcohol-free alkaline texturing solution for monocrystalline silicon wafers, a texturing method, solar cells and a manufacturing method thereof. Background technique [0002] In the production process of solar cells, in order to improve the performance and efficiency of solar cells, it is necessary to make a textured surface on the surface of the silicon wafer. The effective textured structure can make the incident sunlight reflect and refract multiple times on the surface of the silicon wafer, changing the incident light In the direction of progress in the silicon wafer, on the one hand, the optical path is extended, and the absorption rate of infrared light by the silicon wafer is increased; on the other hand, more photons are absorbed in the area near the p-n junction to generate photogenerated carriers. Photogenerated carriers are more easily collected, thus increasing...

AI Technical Summary

Problems solved by technology

[0007] However, with the widespread application of diamond wire-cut silicon wafers, considering the advantages of diamond wire-cut silicon wafers, people no longer use the existing multi-wire unidirectional cutting process.

However, the existing problem is that the damage layer on the surface of the silicon wafer after diamond wire cutting is reduced. If the above-mentioned alkaline texturing liquid is used for texturing, the corrosion rate on the surface of the silicon wafer will be slowed down and uneven, and the corrosion depth will be reduced. Unqualified, which eventually leads to the uneven size of the structured structure pyramid on the surface of the silicon wafer, which in turn reduces the conversion efficiency of the solar cell

In addition, isopropanol is a colorless, transparent, volatile liquid with an odor similar to a mixture of ethanol and acetone. Its vapor can slightly irritate the eyes, nose and throat, and can also be absorbed by the human body through the skin, and isopropanol is volatile. Therefore, in the production process, the airtightness of the equipment is required to be high. After treatment, the waste liquid containing isopropanol is also one of the important sources of pollution in the industry. The follow-up pollution treatment costs are high, which does not meet the company's energy-saving emission reduction and green pollution-free. Require

Images