Special cutting fluid for diamond wire

Abstract

The invention discloses special cutting fluid for a diamond wire. The special cutting fluid comprises the following components in weight percent: 19-59% of polyethylene glycol, 40.5-80.5% of pure water, 0.05-0.2% of anti-rusting agent, 0.05-0.2% of emulsifier and 0.3-0.5% of defoamer. The density and the viscosity of the cutting fluid are smaller than those of the traditional cutting fluid, the cutting fluid has not only good flowability but also easiness in cleaning, the cleaning can be performed according to the normal cleaning process of a silicon wafer after cutting, and the abnormal phenomena can be avoided; the thickness of the silicon wafer, the TTV (total thickness variation) and the WARP for cutting the diamond wire are meet the requirements respectively, and a cell sheet has no abnormities after texturing; and the cutting fluid is low in preparation cost, the cost of the cutting fluid does not exceed 60% of that of the traditional cutting fluid, and the cutting fluid is conductive to replacing the imported cutting fluid.

Description

technical field [0001] The invention relates to a silicon wafer cutting fluid, in particular to a silicon wafer cutting fluid specially used for diamond wire cutting. Background technique [0002] Silicon wafer is the basic material of the semiconductor, solar energy, and liquid crystal display lamp industries. It is divided into monocrystalline silicon wafers and polycrystalline silicon wafers. Silicon wafers with thickness specifications. In the process of processing silicon wafers in the traditional free abrasive wire cutting method, the cutting fluid evenly attaches cutting abrasives such as silicon carbide to the high-speed moving steel wire through the characteristics of suspension, lubrication, dispersion, and cooling, and drives the abrasive through rapid movement. Cut silicon rods. [0003] With the development of the solar energy industry, a new multi-wire cutting method, diamond wire cutting, has emerged, which uses diamond particles fixed on steel wires for cut...

AI Technical Summary

Problems solved by technology

[0006] (1) The cost is high, and the current market price is about 16,000 yuan / ton;

[0007] (2) The mortar after cutting contains the following solids: silicon powder produced when cutting silicon rods, broken silicon carbide particles, larger silicon carbide particles, iron micropowder and some iron oxides produced after steel wire grinding are all harmful The environment produces a lot of pollution, and it must be recycled before it can be discharged, and the recycling cost of silicon carbide is relatively high; it is difficult to meet the requirements of zero pollution to the environment;

[0008] (3) During the cutting process, about 40% of the silicon powder is wasted. The silicon powder lost during the cutting process is distributed in the mortar after cutting. Due to the relatively high viscosity of the mortar and the large amount of single cutting, the existing waste Liquid recovery technology is difficult to effectively separate, and the cost of separation is also very high;

[0009] (4) Since the traditional cutting fluid is used to add silicon carbide for cutting silicon wafers, in order to make the silicon carbide evenly distributed, facilitate cutting and improve cutting quality, the traditional cutting fluid should have high viscosity and low fluidity, which is not conducive to cutting. High-speed cutting, traditional free mortar cutting speed is slow, cutting efficiency is not high,

[0010] (5) Due to the poor applicability of the wire cutting fluid, the diamond wire cutting of silicon wafers is limited. At present, most of the diamond wire cutting should only be used for the processing of silicon crystal rods