Method for cleaning diamond wire-electrode cutting silicon wafer

Abstract

The invention relates to the technical field of cutting silicon wafer post-treatment, and in particular relates to a method for cleaning a diamond wire-electrode cutting silicon wafer. The method comprises the following steps: coarsely cleaning a degummed silicon wafer in an alkaline cleaning agent and lactic acid respectively, wherein the pH of the alkaline cleaning agent is between 9 and 10, the temperature of the alkaline cleaning agent is between 30 and 50 DEG C, and the temperature of the lactic acid is 60 DEG C; and finely cleaning in the alkaline cleaning agent and purified water respectively, wherein the PH of the alkaline cleaning agent is between 9 and 10, and the temperature of the alkaline cleaning agent is between 70 and 90 DEG C. The cleaning method has the advantages that: the silicon wafer surface is cleaner and the surface damaged layer is better removed by increasing pH of the silicon wafer cleaning solution and increasing the temperature, and the cleaning solution plays a surface activation effect in the alkaline etching process of the silicon wafer. When the silicon wafer is etched, the pyramid etching surface has higher coverage rate, and the etching surface is uniform.

Description

technical field [0001] The invention relates to the technical field of post-processing of cut silicon wafers, in particular to a cleaning method for diamond wire cut silicon wafers. Background technique [0002] At present, multi-wire cutting machines are generally used for cutting solar silicon wafers, and MB, HCT, NTC, etc. have a relatively large market share. However, due to the low efficiency of this cutting process, one cut takes 7-8 hours; SiC and PEG are required for cutting. The mixed mortar, the discharge of its waste mortar after cutting seriously pollutes the environment. In view of the above problems, a new cutting process has been developed internationally, diamond wire cutting, its cutting speed is 2 to 3 times that of ordinary wire cutting, and no Using SiC, using water-based cutting fluid that is non-polluting to the environment. However, due to the different cutting principles, the impact on the surface morphology of the silicon wafer is also different. If...

AI Technical Summary

Problems solved by technology

[0002] At present, multi-wire cutting machines are generally used for cutting solar silicon wafers, and MB, HCT, NTC, etc. have a relatively large market share. However, due to the low efficiency of this cutting process, one cut takes 7-8 hours; SiC and PEG are required for cutting. The mixed mortar, the discharge of its waste mortar after cutting seriously pollutes the environment. In view of the above problems, a new cutting process has been developed internationally, diamond wire cutting, its cutting speed is 2 to 3 times that of ordinary wire cutting, and no Using SiC, using water-based cutting fluid that does not pollute the environment

However, due to the different cutting principles, the impact on the surface morphology of the silicon wafer is also different. If the silicon wafer is cleaned normally, the coverage of the pyramid of the silicon wafer after alkali texturing is very small, the reflectivity is low, and the battery conversion efficiency is also low. relatively low