A method of using diamond wire cut solar grade polysilicon wafers

Abstract

The invention discloses a method for cutting solar-grade polysilicon wafers using diamond wire cutting. The polysilicon rods are glued to the sticks after being squared, ground and ground. The resin strip is fixed on the bonding board, and then the bonding board and the polysilicon rod are put into the working cabin, the cutting fluid is preheated and circulated in the working cabin, and the diamond wire is cut into polysilicon wafers, and the polysilicon wafers are placed upside down on the degumming equipment It is made by degumming, ultrasonic cleaning, and drying. The present invention does not produce indole-like cut marks on the surface of the polycrystalline silicon sheet, improves the photoelectric conversion efficiency of the polycrystalline silicon sheet, has high diamond wire cutting speed, high dimensional accuracy of the cut polycrystalline silicon sheet, small error, and a qualified rate of more than 95%. The silicon powder produced by cutting can be recycled, saving precious silicon resources.

Description

technical field [0001] The invention relates to a solar-grade polycrystalline silicon chip cut by diamond wire and a cutting method thereof. Background technique [0002] Solar polycrystalline silicon wafers are used in solar cells, and polycrystalline silicon rods are processed into silicon wafers by wire cutting machines. The difference between monocrystalline silicon and polycrystalline silicon mainly lies in the internal grain orientation. If grains with the same crystal plane orientation grow, it is monocrystalline silicon; otherwise, it is polycrystalline silicon. At present, NTC, MB, and HTC are commonly used to cut polysilicon wafers, and the free mortar cutting process is used. Due to the impurities inside the polysilicon, it is easy to cause disconnection during the cutting process, resulting in a low good rate; Silicon is difficult to recycle, causing serious environmental pollution; silicon powder is difficult to recycle, wasting precious silicon resources; the ...

AI Technical Summary

Problems solved by technology

At present, NTC, MB, and HTC are commonly used to cut polysilicon wafers, and the free mortar cutting process is used. Due to the impurities inside the polysilicon, it is easy to cause disconnection during the cutting process, resulting in a low good rate; Silicon is difficult to recycle, causing serious environmental pollution; silicon powder is difficult to recycle, wasting precious silicon resources; the cutting efficiency is relatively low, and there are also a large number of loss layers on the surface of the silicon wafer, which affects the performance of the cell

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