Alkali etch solution and method for preparing monocrystalline silicon pile fabrics

Abstract

The invention belongs to the field of monocrystalline silicon solar battery production and discloses an alkaline corrosion solution and a method for preparing monocrystalline silicon texture. The solution is a mixed liquor of an alkaline solution, isopropanol and Na2SiO3, and is structurally characterized in containing 0.002 to 0.01 weight percent of Pb(NO3)2 or Pb. The weigh percentage of the alkaline solution is 1 to 3.5 percent, the weight percentage of the isopropanol is 5 to 7 percent, and the weight percentage of Na2SiO3 is 0.2 to 2 percent. The method is to soak a monocrystalline silicon piece in the alkaline solution to perform a corrosion reaction for 20 to 30 minutes under a condition that the alkaline corrosion solution is at a temperature of between 75 and 80 DEG C. The alkaline corrosion solution and the method have the advantages of reducing surface reflectivity of the monocrystalline silicon piece, preparing a fine texturing 'pyramid', along with low cost, simple operation and stable and effective preparation of the monocrystalline silicon texture.

Description

technical field [0001] The invention belongs to the field of manufacturing monocrystalline silicon solar cells, and relates to an alkali etching solution and method for preparing monocrystalline silicon textured surfaces. Background technique [0002] Since the advent of solar cells, the entire market is still dominated by monocrystalline silicon solar cells so far. Improving the stability of the preparation of the textured surface of monocrystalline silicon wafers and preparing the pyramids of the textured surface of monocrystalline silicon wafers into nanoscale has always been the focus of technical personnel in this field. One of the goals to strive for. Improving the stability of the monocrystalline silicon textured surface preparation can reduce the frequency of solution preparation and greatly improve production efficiency; reducing the volume of the monocrystalline silicon textured pyramid can eliminate many hidden dangers in the solar cell production process. Theref...

AI Technical Summary

Problems solved by technology

[0004] Although the monocrystalline silicon wafer suede preparation technology was developed earlier, the traditional process can be put into mass production, but in the traditional process, when preparing the single crystal silicon wafer suede by alkali corrosion, the concentration of alkali solution, temperature, corrosion time, isopropyl Alcohol added amount, Na 2 SiO 3 A series of related process parameters such as the amount of addition require very precise control, otherwise it will cause extreme instability in the texturing process, as well as an increase in the frequency of solution replacement and the rework rate of suede preparation, wasting unnecessary property and time; and the prepared suede The unevenness of the surface will increase the reflection of light, which will eventually affect the conversion efficiency of solar cells.

[0005] With the continuous improvement of the process, the silicon wafer thinning process has been replaced by the suede process. It is almost impossible for the traditional process to ensure the complete removal of the damaged layer during the suede preparation process and relatively reduce the volume of the suede pyramid; and The relatively large size of the pyramid will increase the incidence of debris in the production process of the cell, and at the same time, the reflection of light from different angles will also increase, which will eventually affect the conversion efficiency of the solar cell

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