CN113736550A

CN113736550A - Diamond wire cutting fluid for circulating system of slicing equipment and preparation method of diamond wire cutting fluid

Info

Publication number: CN113736550A
Application number: CN202111029710.3A
Authority: CN
Inventors: 郭熹; 刘治洲; 王波
Original assignee: Jiangsu Jiejie Semiconductor New Material Co ltd
Current assignee: Jiangsu Jiejie Semiconductor New Material Co ltd
Priority date: 2021-09-02
Filing date: 2021-09-02
Publication date: 2021-12-03

Abstract

The invention discloses diamond wire cutting fluid for a circulating system of slicing equipment, which comprises, by weight, 20-30 parts of a lubricant, 10-15 parts of a water-soluble penetrating agent, 1-5 parts of an oil-soluble penetrating agent compound, 0.5-5 parts of a defoaming agent, 20-30 parts of a solubilizer, 0.5-3 parts of an emulsifier, 0.1-2 parts of a dispersant and the balance of deionized water. The diamond wire cutting fluid has the beneficial effects that the diamond wire cutting fluid has strong cleaning capability, can effectively remove residual oily dirt on the surface of a silicon wafer, silicon powder agglomeration and caking and the like, can avoid the aggregation of silicon powder cutting scraps and organic residues in equipment, and can prevent the adhesion from forming and blocking a pipeline.

Description

Diamond wire cutting fluid for circulating system of slicing equipment and preparation method of diamond wire cutting fluid

Technical Field

The invention relates to the technical field of silicon wafer crystal cutting, in particular to diamond wire cutting fluid for a circulating system of slicing equipment and a preparation method thereof.

Background

With the rapid development of the photovoltaic industry, the solar power generation cost is greatly reduced; silicon wafers are used as basic materials of the photovoltaic industry, slicing processing is a main process for determining the quality of the silicon wafers, the conversion efficiency of a photovoltaic cell can be seriously influenced by the defects of silicon wafer stress, surface layer and subsurface layer damage, edge breakage and the like generated during slicing, and the performance of a cutting liquid is one of key factors influencing the cutting efficiency and quality of the silicon wafers;

in the traditional slicing equipment, water-adding diluent of diamond wire cutting fluid is sprayed to the vicinity of a cutting surface through a pipeline system of the equipment and is brought into a cutting gap by a diamond wire moving at high speed, so that the effects of lubrication and cooling are achieved; the diluent entering the gap carries impurities such as cut silicon powder scraps and the like, falls back to a diluent storage cylinder of the equipment, and is brought into a pipeline system again by a circulating pump for recycling; after each silicon rod is cut, the diluent passes through a filter pressing recovery system, impurities such as silicon powder and the like are filtered, and the silicon rod is directly discharged after harmless treatment; in each cutting process, 500 kilograms of waste water and 1-2 kilograms of cutting fluid are discharged, so that the cost and the difficulty of environmental protection treatment are increased in a long term, and meanwhile, the discharged waste water and the cutting fluid still have partial use values, so that great waste is caused;

the circulating system of the slicing equipment is characterized in that a plurality of slicing equipment are connected in series through a circulating pipeline and connected with a filter pressing system, and waste water generated by cutting is filtered by a filter pressing recovery system and then returns to the slicing equipment again to continue to participate in cutting; the whole system regularly supplements pure water and cutting fluid, realizes the reutilization of most of wastewater and cutting fluid, greatly reduces the discharge of sewage and waste, reduces the treatment cost, and has extremely high economic benefit and social benefit; firstly, the cutting fluid is dissolved in pure water and exists in the form of emulsion, the stability of the emulsion is closely related to factors such as temperature, flow rate, time and the like, and the factors such as flow distance, storage time and the like of the emulsion in the circulating system are far longer than those of the traditional slicing mode, so that the high requirement is provided for the stability of the aqueous solution of the cutting fluid; secondly, the cutting liquid after slicing processing does not directly carry silicon powder to enter a cutting gap in a circulating manner, but enters the cutting gap after the silicon powder is filtered out by a filter pressing system, and the silicon powder in the cutting liquid can play a certain lubricating role, so that the penetration and the wettability of the cutting liquid adapting to a circulating system are improved, and the lubricating property is improved; thirdly, after being filtered by a circulating system, the component proportion of the original cutting fluid may be changed greatly, which results in the mismatching of the performance and the requirement, and the situation is worsened continuously along with the continuous addition of new filtered cutting fluid, wherein the most prominent is lubricity and defoaming property, and even the production is interrupted due to foam overflow; although the reduction can be achieved by discharging part of the waste water and supplementing new diluent, the existing cutting fluid product still cannot meet the requirement of a circulating system, and fundamental changes need to be made on a formula system; paradoxically, however, the stability of the emulsion is improved and the content of oily substances needs to be reduced; the increase of the lubricity requires the increase of the content of oily substances; in addition, the raw materials of the existing defoaming agent suitable for the cutting fluid are also oily substances, the stability of the diluted emulsion is deteriorated due to the addition of the defoaming agent, and the defoaming performance is further deteriorated due to the reduction of the defoaming agent;

the diamond wire cutting fluid adapting to the circulating system has the following functions: (1) the permeability is good: the cutting fluid should penetrate into the cutting gap deeply in time, and a lubricating protective film is formed between the wire mesh and the silicon wafer and between the wire mesh and the scraps, so that the cutting resistance is reduced, and the damage, the wire mark and the hidden crack caused by the diamond wire are reduced; (2) the cooling performance is strong: high heat generated by cutting is absorbed by the crystalline silicon mostly except for part of the high heat taken away by the cutting liquid, and local silicon chip deformation can be caused by high temperature; therefore, the cutting fluid needs to have good heat transfer and cooling performance; (3) the silicon powder cutting chips can be dispersed in time: silicon powder cuttings formed by cutting need to be dispersed in time, and the silicon chips are prevented from being aggregated to form clusters, so that the silicon chips are scratched and even wire meshes are broken; (4) has good cleaning capability: a large amount of scraps and silicon powder generated in the cutting process are easy to form adhesion agglomeration, so that the scraps can be wrapped by cutting liquid, and the scraps are easy to fall off and clean; (5) all components in the cutting fluid formula can stably coexist, the adsorbability is poor, and the performance damage caused by component separation after the components are filtered by a filter pressing system can be avoided; (6) the emulsion-breaking-free oil-floating agent can be kept stable for a long time in a circulating system, and does not break emulsion, float oil or precipitate; (7) the cutting fluid also has the capabilities of rust prevention and bacteriostasis, and production interruption caused by corrosion shutdown of equipment in the long-term use process is avoided. Therefore, how to maintain the stability and performance of the cutting fluid is an important point in adapting the cutting fluid to the circulatory system.

Disclosure of Invention

In view of the problems, the invention discloses diamond wire cutting fluid suitable for a circulating system and a preparation method thereof, the cutting fluid has excellent permeability and lubricity, good dispersibility and high stability, and meanwhile, the using addition amount of the cutting fluid is reduced by 30% compared with that of the existing product, so that the use cost and the wastewater treatment difficulty can be effectively reduced.

The diamond wire cutting fluid comprises, by weight, 20-30 parts of a lubricant, 10-15 parts of a water-soluble penetrant, 1-5 parts of an oil-soluble penetrant complex, 0.5-5 parts of a defoaming agent, 20-30 parts of a solubilizer, 0.5-3 parts of an emulsifier, 0.1-2 parts of a dispersant, and the balance deionized water.

The technical scheme is further supplemented, the lubricant is any one or combination of monohydric alcohol and polyol polyether, and the monohydric alcohol or the polyol polyether is one or a compound of two or more of alkylphenol polyoxyethylene polyoxypropylene ether, propylene glycol polyoxyethylene polyoxypropylene ether, allyl polyoxyethylene polyoxypropylene ether and fatty alcohol polyoxyethylene polyoxypropylene ether with six to twelve carbon atoms; the six-carbon to twelve-carbon refers to the number of carbon atoms in an aliphatic alcohol chain, monohydric alcohol and polyol polyether have excellent lubricating property and permeability and have the advantages of dispersion, cooling and cleaning, and the polyether penetrant and the defoamer are polyether-type penetrants and have more same functional groups, so that the penetrants and the defoamers are easy to dissolve and compound, the efficacy after compounding exceeds the sum of the penetrants and the defoamers, the penetration capacity is further improved, and the generation of foams is inhibited.

The technical scheme is further supplemented, and the water-soluble penetrating agent is one or combination of isomeric alcohol polyoxyethylene ether and isomeric alcohol polyoxyethylene ether phosphate; the isomeric alcohol polyoxyethylene ether or isomeric alcohol polyoxyethylene ether phosphate is one or a compound of two or more of isooctanol polyoxyethylene ether, isomeric dodecyl alcohol polyoxyethylene ether, isomeric tridecanol polyoxyethylene ether, isooctanol polyoxyethylene ether phosphate, isomeric dodecyl alcohol polyoxyethylene ether phosphate and isomeric tridecanol polyoxyethylene ether phosphate; the silicon wafer cutting fluid is preferably prepared from isomeric alcohol polyoxyethylene ether which has excellent permeability and water solubility, and has more same functional groups as fatty alcohol polyoxyethylene polyoxypropylene ether in the lubricant, and the isomeric alcohol polyoxyethylene ether and the fatty alcohol polyoxyethylene polyoxypropylene ether are compounded to form molecular mutual solubility with polyether and are tightly combined, so that the permeability and the dispersibility of the fatty alcohol polyoxyethylene polyoxypropylene ether can be further increased, the silicon wafer cutting fluid can rapidly permeate between silicon wafers, and silicon powder generated by cutting can be taken away.

Supplementing the technical scheme further, the oil-soluble penetrant compound is a compound of perfluoroalkyl polyether, oleic acid and sodium oleate; the perfluoroalkyl polyether is a perfluoro substituted alkyl and ethylene oxide polymer, has a similar structure with the lubricant and the water-soluble penetrant, is easy to form mutual solubility with the perfluoro substituted alkyl and the ethylene oxide polymer, and the oleic acid (sodium) is octadecenoic acid (sodium) which is insoluble in water and can be dissolved in water after being fused with the perfluoroalkyl polyether according to a certain proportion, and the critical micelle concentration is greatly reduced; the compound has excellent heat resistance and cold resistance, can stabilize other oil-soluble substances in a system, and improves the stability of the system.

The technical scheme is further supplemented, the defoaming agent is one or the combination of two or more of alkynediol or alkynediol polyether or gemini organic silicon polyether or polyether defoaming agent, and the alkynediol polyether, the gemini organic silicon polyether and other polyether defoaming agents have a large number of lipophilic groups/branched groups and unsaturated silane structures, so that after being compounded with straight-chain polyether, the water solubility can be remarkably increased, and the defoaming and foam inhibiting capabilities of the defoaming agent and the gemini organic silicon polyether are fully exerted; the polyether defoamer has the advantages that the polyether defoamer can achieve both foam inhibition and defoaming effects, is low in foaming height and high in defoaming speed, can effectively prevent foams from overflowing during use, avoids the defects of dirt, spots and the like caused by persistent bubbles appearing on the surface of a silicon wafer, is low in surface tension, is obvious in foam inhibition and defoaming effects, and can continuously defoam for a long time; wherein, the polyether defoamer comprises one or the combination of two or more of GP type glycerol polyether, GPE type polyoxyethylene polyoxypropylene glycerol ether or GPES type stearate polyoxyethylene polyoxypropylene glycerol ether;

the technical scheme is further supplemented, and the solubilizer is any one or combination of dihydric alcohol and polyhydric alcohol; the dihydric alcohol comprises any one or combination of two or more of ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, diethylene glycol and isohexylene glycol; wherein, the dihydric alcohol or the polyhydric alcohol is an excellent non-ionic water-soluble polymer, the polyhydric alcohol can be mixed with water and polyether to form a good synergistic effect, has strong dissolving capacity on polar substances, is non-toxic and nonvolatile, is friendly to biology and environment, preferably, the solubilizer selects polyethylene glycol with low relative molecular mass, has better compatibility, is matched with the polyhydric fatty alcohol polyoxyethylene ether for use, can reduce the adhesive force of silicon powder on the surface of a silicon wafer, disperses the silicon powder in cutting fluid and carries away the silicon powder, has better cleaning effect, fully dissolves and mixes polyether without increasing the addition amount of the polyether, on one hand, avoids the polyether from being adhered on the surface of the silicon wafer to cause dirty sheets, on the other hand, can further increase the lubricating, permeating, defoaming and cleaning effects of the polyether, therefore, under the condition of the same performance, the use amount of organic substances of the silicon wafer cutting fluid is greatly reduced, effectively reducing the difficulty of silicon wafer cleaning and wastewater treatment.

The technical scheme is further supplemented, the emulsifier is one or a combination of a fatty alcohol-polyoxyethylene condensate and fatty acid polyol ester, the fatty alcohol-polyoxyethylene condensate is one or a combination of six-to fifteen-carbon straight-chain alkanol polyoxyethylene ether, and the fatty acid polyol ester is one or a combination of two or more of sorbitan monooleate, polyoxyethylene sorbitan monostearate, monoglyceride and sucrose fatty acid ester; preferably, the emulsifier adopts fatty acid polyol ester, fatty acid is used as a hydrophobic group, and after esterification with a polyol hydrophilic group, the emulsifier can wrap and disperse an oil phase in a water phase, plays a good emulsification role in a polyether system, can be fully dissolved in the polyether system, forms stable oil-in-water microemulsion droplets, and can remarkably increase the permeability and lubricity.

The technical scheme is further supplemented, the dispersing agent adopts one or a compound of two or more than two of water-soluble polymer polyelectrolytes, is adsorbed on the surface of the silicon powder in an aqueous solution, realizes effective dispersion of the silicon powder by utilizing uniform charge distribution, and has good hard water resistance; in detail, one or more than two compounds of acrylic acid homopolymer, phosphono carboxylic acid copolymer, naphthalene sulfonate formaldehyde condensate and acrylic acid sulfonic acid copolymer can effectively disperse silicon powder cuttings under the condition of low addition amount, and reduce the risk of diamond wire breakage in processing.

The silicon wafer cutting fluid further comprises an antirust agent and a bactericide, wherein the antirust agent is 0.1-5 parts by weight, is one or combination of two or more of triethanolamine oleate, sulfonated oil, methyl benzotriazole or isopropyl benzotriazole, and can effectively protect the diamond wire from corrosion in a humid and acidic environment, maintain the mechanical strength and the fluid carrying capacity of the diamond wire and reduce the wire breakage rate; the bactericide is 0.01-3 parts by weight, and is one or the combination of quaternary ammonium salt and oxazoline bactericide; further, the bactericide is one or combination of two or more of dodecyl trimethyl ammonium chloride, dodecyl dimethyl benzyl ammonium chloride, benzisothiazolinone and isothiazolinone; and the bactericide is added to inhibit the breeding of bacteria and prevent the silicon wafer cutting fluid from mildewing, losing efficacy, being rotten and smelling.

A preparation method of diamond wire cutting fluid for a circulating system of slicing equipment comprises the following steps:

(a) mixing a solubilizer, a lubricant, an oil-soluble penetrating agent and a dispersant for the first time to obtain a primary mixed solution; the mixing temperature is 20-30 ℃, the rotating speed is 45-55 r/m, and the time is 10-20 minutes;

(b) mixing the primary mixed solution obtained in the step a) with a defoaming agent, an emulsifying agent, a bactericide, an antirust agent and water for the second time to obtain a secondary mixed solution; the mixing temperature is 35-45 deg.C, the rotation speed is 50-60 r/min, and the time is 30-40 min.

(c) Mixing the secondary mixed liquid obtained in the step b) with a water-soluble penetrating agent to obtain diamond wire cutting liquid; the mixing temperature is 20-30 deg.C, the rotation speed is 50-60 r/min, and the time is 5-10 min.

The diamond wire cutting fluid has strong cleaning capability, can effectively remove residual oily dirt on the surface of a silicon wafer, silicon powder agglomeration and caking and the like, can avoid the aggregation of silicon powder cutting scraps and organic residues in equipment, and can prevent the adhesion from forming and blocking a pipeline; due to the size problem of the large-size silicon wafer, a large amount of silicon powder is generated in the cutting process and attached to the surface of the silicon wafer, the dispersing agent with charges can be adsorbed on the surface of the silicon powder, the silicon powder is prevented from being aggregated, the silicon powder cutting scraps can be efficiently dispersed under the condition of low addition amount, and the wire breakage risk of a diamond wire in processing is reduced; furthermore, water-soluble polymer polyelectrolyte is adopted as a dispersing agent and is adsorbed on the surface of the silicon powder in an aqueous solution, the silicon powder can be effectively dispersed by utilizing uniform charge distribution, and the silicon powder has good hard water resistance and is convenient for enterprises to popularize and use; furthermore, the polyethers can be effectively compounded, the total using amount is reduced, and polyethers with different performances can be combined on a molecular layer to fully play respective roles; the alkynediol polyether, the Gemini organic silicon polyether and other polyether defoaming agents have a similar straight-chain structure with straight-chain polyether, and can improve water solubility by combining with the polyether, so that the defoaming and foam inhibiting capabilities of the polyether and the Gemini organic silicon polyether are greatly improved; the colloidal cluster formed by polyether molecules has good dispersibility, and other functional additives such as antirust agents, bacteriostatic agents and the like can be effectively dispersed without adding an ionic charge dispersing agent into the system, so that the dosage of the additives is reduced, and the efficiency is improved.

Detailed Description

Example 1

28 parts of propylene glycol, 25 parts of propylene glycol polyoxyethylene polyoxypropylene ether, 2 parts of oil-soluble penetrating agent and 0.2 part of acrylic sulfonic acid copolymer, mixing and stirring the components for 10 minutes at the stirring speed of 50 revolutions per minute at the temperature of 25 ℃, then adding 4 parts of acetylenic diol polyether, 1 part of sorbitan monooleate, 1.5 parts of triethanolamine oleate, 1.5 parts of dodecyl trimethyl ammonium chloride and 24.8 parts of deionized water, mixing and stirring the components for 40 minutes at the stirring speed of 50 revolutions per minute at the temperature of 35 ℃, then adding 12 parts of isooctanol polyoxyethylene ether, mixing and stirring the components for 5 minutes at the stirring speed of 50 revolutions per minute at the temperature of 30 ℃ to obtain the diamond wire cutting fluid.

Example 2

25 parts of polyethylene glycol, 15 parts of propylene glycol polyoxyethylene polyoxypropylene ether, 10 parts of allyl polyoxyethylene polyoxypropylene ether, 3 parts of oil-soluble penetrating agent and 0.5 part of acrylic sulfonic acid copolymer, wherein the components are mixed and stirred at the stirring speed of 50 revolutions per minute for 10 minutes at 25 ℃, 2.5 parts of acetylenic diol polyether, 1 part of GP-type glyceryl polyether, 1 part of sorbitan monooleate, 1 part of monoglyceride, 1 part of methylbenzotriazole, 1.5 parts of dodecyl trimethyl ammonium chloride and 25 parts of deionized water, the components are mixed and stirred at the stirring speed of 50 revolutions per minute for 40 minutes at 35 ℃, 13 parts of isomeric dodecyl polyoxyethylene ether are added, and the components are mixed and stirred at the stirring speed of 50 revolutions per minute for 10 minutes at 30 ℃ to obtain the diamond wire cutting fluid.

Example 3

12 parts of propylene glycol, 8 parts of polyethylene glycol, 20 parts of alkylphenol polyoxyethylene polyoxypropylene ether, 10 parts of propylene glycol polyoxyethylene polyoxypropylene ether, 10 parts of allyl polyoxyethylene polyoxypropylene ether, 4 parts of oil-soluble penetrating agent and 0.5 part of phosphono carboxylic acid copolymer, wherein the components are mixed and stirred at the stirring speed of 50 revolutions/minute for 10 minutes at the temperature of 25 ℃, 1.5 parts of alkyne glycol polyether, 1.5 parts of GPE type polyoxyethylene polyoxypropylene glycerol ether, 1 part of polyoxyethylene sorbitan monostearate, 1 part of glycerol monoglyceride, 1 part of triethanolamine oleate, 0.5 part of sulfonated oil, 1 part of benzisothiazolinone, 0.5 part of isothiazolinone and 24.5 parts of deionized water are added, the mixture is stirred at the stirring speed of 50 revolutions/minute at the temperature of 35 ℃ for 40 minutes, 11 parts of isotridecanol polyoxyethylene ether and 2 parts of isotridecanol polyoxyethylene ether phosphate are added, and the mixture is stirred at the temperature of 30 ℃, and mixing and stirring the mixture for 10 minutes at the stirring speed of 50 revolutions per minute to obtain the diamond wire cutting fluid.

Example 4

15 parts of polyethylene glycol, 10 parts of isohexane glycol, 25 parts of six-to eight-carbon fatty alcohol polyoxyethylene polyoxypropylene ether, 5 parts of oil-soluble penetrating agent, 0.5 part of phosphono carboxylic acid copolymer, mixing and stirring the mixture for 10 minutes at the stirring speed of 50 revolutions per minute at the temperature of 25 ℃, then adding 1.5 parts of acetylenic diol polyether, 1.5 parts of GPES type stearate polyoxyethylene polyoxypropylene glycerol ether, 2 parts of sorbitan monooleate, 1 part of polyoxyethylene sorbitan monostearate, 1.5 parts of methylbenzotriazole, 1.5 parts of dodecyl trimethyl ammonium chloride and 24.5 parts of deionized water, mixing and stirring the mixture for 40 minutes at the temperature of 35 ℃ at the rotating speed of 50 revolutions per minute, then adding 13 parts of isomeric tridecanol polyoxyethylene ether and 2 parts of isomeric tridecanol polyoxyethylene ether phosphate, and mixing and stirring the mixture for 10 minutes at the stirring speed of 50 revolutions per minute at the temperature of 30 ℃ to obtain the diamond wire cutting fluid.

Example 5

5 parts of propylene glycol, 10 parts of polyethylene glycol, 5 parts of isohexane glycol, 20 parts of propylene glycol polyoxyethylene polyoxypropylene ether, 10 parts of allyl polyoxyethylene polyoxypropylene ether, 3 parts of oil-soluble penetrant, 0.5 part of naphthalene sulfonate formaldehyde condensate and 0.5 part of acrylic sulfonic acid copolymer, wherein the components are mixed and stirred at the stirring speed of 50 revolutions per minute for 10 minutes at the temperature of 25 ℃, 2 parts of alkyne glycol polyether, 1 part of GPES type stearate polyoxyethylene polyoxypropylene ether, 2 parts of monoglyceride, 2 parts of sucrose fatty acid ester, 1.5 parts of isopropyl benzene triazole, 0.6 part of benzisothiazolinone, 0.9 part of isothiazolinone and 25 parts of deionized water are added, the mixture is stirred at the stirring speed of 50 revolutions per minute for 40 minutes at the temperature of 35 ℃, 9 parts of isooctanol polyoxyethylene ether and 3 parts of isooctanol polyoxyethylene ether phosphate are added, the mixture is mixed and stirred at the stirring speed of 50 revolutions per minute for 10 minutes at the temperature of 30 ℃, and obtaining the diamond wire cutting fluid.

Control group

The samples of the above examples and the control group samples were tested for key indicators at the same temperature and the same dilution ratio, with the difference that: the control sample used a cutting fluid different from the non-full polyether type of the above example; wherein, the embodiment and the comparison group adopt the corresponding filter-pressing recovered water for dilution.

(1) Correlation index testing

The key indicators of the diamond wire cutting fluids provided by examples 1-5 and the control were tested and the results are shown in table 1.

TABLE 1 comparison data of key index test for cutting fluids provided in examples 1-5 and control

As shown in Table 1, the detection proves that the diamond wire cutting fluid provided by the invention is superior to a control group in key indexes, realizes improvement in permeability, defoaming property, surface tension and the like, and has strong adaptability to filter-pressing recycled water.

(2) Cut silicon wafer testing

The slicing equipment and the process method of the embodiment and the slicing comparison test of the silicon wafer with the same size are adopted, and the differences are that: a cutting fluid of a non-all polyether type different from the above examples was used; the addition amount recommended by a contrast group cutting fluid supplier is adopted; the recovered filter-pressing water corresponding to each example and control group was used for dilution.

The effect data of the method for cutting silicon wafers by diamond wires provided in examples 1 to 5 and the control group were examined, and the results are shown in table 2.

Table 2 effect data of the method for cutting silicon wafer by diamond wire provided in examples 1 to 5 and the control group

As can be seen from table 2, experiments prove that the filter-pressing recovered water obtained by using respective formulas for filter pressing in the examples is superior to the control group in various indexes; the silicon wafer diamond wire cutting fluid suitable for the circulating system provided by the invention can effectively improve the lubricating and penetrating properties of cooling water in slicing processing, improve the surface appearance of the silicon wafer and reduce the incidence rate and the contamination proportion of surface defects under the condition of keeping the diluent stable for a long time.

The technical solutions described above only represent the preferred technical solutions of the present invention, and some possible modifications to some parts of the technical solutions by those skilled in the art all represent the principles of the present invention, and fall within the protection scope of the present invention.

Claims

1. The diamond wire cutting fluid for the circulating system of slicing equipment is characterized by comprising, by weight, 20-30 parts of a lubricant, 10-15 parts of a water-soluble penetrating agent, 1-5 parts of an oil-soluble penetrating agent compound, 0.5-5 parts of a defoaming agent, 20-30 parts of a solubilizer, 0.5-3 parts of an emulsifier, 0.1-2 parts of a dispersant and the balance deionized water.

2. A diamond wire cutting fluid for a slicing apparatus circulation system according to claim 1, wherein the lubricant is any one of monohydric alcohol, polyol polyether or a combination of both.

3. A diamond wire cutting fluid for a slicing apparatus circulation system according to claim 2, wherein the water-soluble penetrant is one of or a combination of isomeric alcohol polyoxyethylene ether and isomeric alcohol polyoxyethylene ether phosphate.

4. The diamond wire cutting fluid for the circulating system of slicing equipment as claimed in claim 1, wherein the oil-soluble penetrant compound is a compound of perfluoroalkyl polyether, oleic acid and sodium oleate.

5. The diamond wire cutting fluid for the circulating system of the slicing device as claimed in claim 1, wherein the defoaming agent is one or a combination of two or more of acetylene glycol or acetylene glycol polyether or gemini silicone polyether or polyether defoaming agent.

6. A diamond wire cutting fluid for a slicing device circulation system according to claim 1, wherein the solubilizer is any one or combination of dihydric alcohol and polyhydric alcohol.

7. A diamond wire cutting fluid for a circulating system of a slicing device according to claim 1, wherein the emulsifier is any one or a combination of fatty alcohol-polyoxyethylene condensate and fatty acid polyol ester.

8. The diamond wire cutting fluid for the circulating system of slicing equipment as claimed in claim 1, wherein the dispersant is one or a mixture of two or more of acrylic acid homopolymer, phosphonocarboxylic acid copolymer, naphthalene sulfonate formaldehyde condensate and acrylic acid sulfonic acid copolymer.

9. The diamond wire cutting fluid for the circulating system of slicing equipment as claimed in claim 1, wherein the silicon wafer cutting fluid further comprises 0.1-5 parts of an antirust agent and 0.01-3 parts of a bactericide, wherein the antirust agent is one or a combination of two or more of triethanolamine oleate, sulfonated oil, methylbenzotriazole or isopropylbenzotriazol; the bactericide is one or combination of quaternary ammonium salt and oxazoline bactericide.

10. The preparation method of the diamond wire cutting fluid for the circulating system of the slicing device as claimed in any one of claims 1 to 9, comprising the steps of: