WO2018221972A2 - Cutting oil composition - Google Patents

Abstract

The present invention relates to a cutting oil composition, and is intended to provide a cutting oil composition, which is remarkably excellent compared with a conventional cutting oil composition in view of layer separation, dispersibility, viscosity, the time of ingot washing after sawing, and the degree of wafer warpage after sawing. The cutting oil composition of the present invention contains a mineral oil represented by chemical formulas 1 to 3 and highly hydrogenated, bentonite clay as a thickener, and glycerine tri oleate as a dispersant. The present invention relates to a cutting method using the cutting oil composition.

Description

Cutting oil composition

The present invention relates to a cutting oil composition used during a wire saw cutting process. In particular, the present invention relates to wire saw cutting oil compositions comprising highly hydrogenated hydrocarbon distillates, thickeners and dispersants.

Wire saw cutting is the primary method of slicing ingots to produce thin wafers used in the integrated circuit and photovoltaic industries.

This method is also commonly used in the manufacture of wafers of other materials, such as sapphire, silicon carbide or ceramic substrates.

The wire saw typically has a web or wireweb of fine metal wires, wherein the individual wires have a diameter of about 0.15 mm and at a distance of 0.1 to 1.0 mm through a series of spools, pulleys and wire guides. Arranged parallel to each other. Cutting is accomplished by contacting a workpiece such as a substrate with a moving wire to which the cutting oil composition is applied.

The conventional wire saw cutting process uses a composition prepared by mixing abrasive particles made of a hard material such as silicon carbide particles in a cutting oil composition including mineral oil, thickener, dispersant, and the like in an approximately 1: 1 weight ratio.

The cutting oil composition is a liquid that provides lubrication and cooling and allows the abrasive to contact the workpiece being cut by retaining the abrasive on the wire.

To achieve optimal performance, coolant requires a good balance of lubricity and viscosity. If the lubricity is excessive, the fine abrasive grains do not adhere to the workpiece and the cutting force is reduced, and if the lubricity is insufficient, the individual fine abrasive grains do not exhibit sufficient cutting ability.

The cutting oil composition may be a non-aqueous material such as mineral oil, kerosene, polyethylene glycol, polypropylene glycol or other polyalkylene glycols, and hydrophilic materials may also be used in the wire saw cutting process.

The present invention relates to a cutting oil composition used during a wire saw cutting process. In the conventional cutting oil composition, it has the disadvantage of separation of the layer, the dispersibility, the viscosity is too low or high, or the ingot cleaning time is too long after Sawing, or the wafer warpage after Sawing In many cases, the degree was a big disadvantage.

That is, in the case of the conventional cutting oil composition, when comprehensively evaluating the delamination, dispersibility, viscosity, post-swing cleaning time, and post-swing wafer warpage, one or more of these characteristics may be poor and correspond to an unsuitable cutting oil composition. It was a situation.

The present invention is not only poor when one or more properties are evaluated when all the properties related to the layer separation, dispersibility, viscosity, post-swing cleaning time, and post-swing wafer warpage are not poor, and when these properties are comprehensively evaluated, A cutting oil composition can be provided which is remarkably superior in all properties as compared to the cutting oil composition.

The present invention has been completed in order to achieve the above object, in the present invention, first, the invention is to invent a highly hydrogenated hydrocarbon represented by the formula (1), and then, a highly hydrogenated hydrocarbon represented by the formula (1) to (3) By mixing a thickener and a dispersant in the invention, the invention has been invented a cutting oil composition having properties that are remarkably excellent in layer separation, dispersibility, viscosity, ingot cleaning time after sawing, and wafer warping after sawing.

The cutting oil composition of the present invention according to one embodiment firstly comprises a mineral oil which is a hydrocarbon represented by the following Chemical Formulas 1 to 3 which are highly hydrogenated.

[Formula 1]

R1- (CnH2n-4) a-R2

[Formula 2]

R3- (CnH2n-2) b-R4

[Formula 3]

R5- (CnH2n) c-R6

In Formulas 1 to 3, n is 5 or 6, and R1, R2, R3, R4, R5, and R6 are each H or OH.

Cutting oil composition of the present invention according to an embodiment, in the formula (a) is a formula of 1 to 7 to 20, b of the formula 2 is 39 to 52, highly hydrogenated, characterized in that c of 39 is 39 to 41 Cutting oil composition which is a mineral oil which is a treated hydrocarbon.

The cutting oil composition of the present invention according to one embodiment may be a cutting oil composition further comprising a thickener and a dispersant.

The cutting oil composition of the present invention according to one embodiment may be a cutting oil composition in which the thickener is bentonite clay and the dispersant is glycerin trioleate.

Cutting oil composition of the present invention according to one embodiment may be a cutting oil composition of 65 to 93% by weight mineral oil, 0.7 to 3% by weight bentonite, 5 to 35% by weight glycerin trioleate, more preferred cutting oil composition is, Cutting oil composition may be 70 to 90% by weight of oil, 1 to 2% by weight of bentonite, 9 to 29% by weight of glycerin trioleate.

The cutting method of the present invention according to one embodiment is a method of cutting using the cutting oil composition.

The present invention exhibits the effect of providing a cutting oil composition which is remarkably excellent in overall layer separation, dispersibility, viscosity, wafer cleaning time after sawing, and wafer warping after sawing.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In general, the nomenclature used herein is well known and commonly used in the art.

Throughout this specification, when a part includes a certain component, it means that it may further include other components, except to exclude other components unless otherwise stated.

EXAMPLE

In Examples and Comparative Examples carried out in the following A, B, C, D item was evaluated based on the following criteria.

1) Viscosity Measurement:

Viscosity measurement was performed using a DV-II + Pro model from Brookfield. Spindle No. Evaluated at 50 rpm using 62. In this case, a viscosity in the range of 90 to 140 mPa · s at 25 ° C. is suitable for the cutting oil composition.

2) Delamination Measurement:

In the delamination measurement, silicon carbide (SiC) was mixed with the cutting oil to evaluate whether delamination occurred. The cutting oil: SiC mixing ratio was mixed at a weight ratio of 1: 1, and left at room temperature for 24 hours, and then at the top of the liquid. Visually assessing whether delamination occurred was divided into no delamination and with delamination. In this case, it is suitable as the cutting oil composition that no delamination occurs.

3) Dispersibility Measurement:

Dispersibility was evaluated by mixing silicon carbide (SiC) in the cutting oil, and the degree of dispersion of SiC in the cutting oil was visually evaluated and classified into good and bad. What was evaluated as good at this time is suitable as a cutting oil composition.

4) Measurement of wafer cleaning time after Sawing:

The wafer cleaning time after sawing was measured by evaluating the time when most of the cutting oil and SiC that existed between the wafers were discharged over time after soaking the wafer in the cleaning solution. At this time, the thing evaluated by 60 minutes or less is excellent as a cutting oil composition.

5) Measurement of wafer warpage after sawing:

Wafer warpage degree measurement after sawing was performed using the equipment to evaluate the warpage degree of individual wafers after cleaning was completed. At this time, the warping degree of the wafer after sawing was evaluated as 10㎛ or less is excellent as the cutting oil composition.

Α. Example  1 to 3 and Comparative example  1, 2: evaluation of the numerical range of a in formula 1, b in formula 2, c in formula 3

In the cutting oil composition including the mineral oil represented by the following Chemical Formulas 1 to 3, an evaluation for determining the numerical range of a in Chemical Formula 1, b in Chemical Formula 2, and c in Chemical Formula 3 was performed and described in Table 1.

[Formula 1]

R1- (CnH2n-4) a-R2

[Formula 2]

R3- (CnH2n-2) b-R4

[Formula 3]

R5- (CnH2n) c-R6

In Formulas 1 to 3, n is 5 or 6, and R1, R2, R3, R4, R5, and R6 are each H or OH.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 a 7 18 20 5 39 b 52 39 41 38 31 c 41 43 39 57 30 Mineral oil content wt% 90 90 90 90 90 Bentonite clay content wt% One One One One One Glycerine tri oleate content wt% 9 9 9 9 9 Coolant + SiC = 1: 1 Separation No layer separation No layer separation No layer separation With layer separation (3mm) No layer separation Dispersibility Good Good Good Bad Good Viscosity (mPa.s@25℃) 90 100 120 70 180 Check wafer cleaning time after sawing 25 minutes 30 minutes 40 minutes 65 minutes 70 minutes Check wafer warpage after sawing 9.9 μm 7.5㎛ 7.7㎛ 13.8㎛ 12.2㎛

As shown in Table 1 above, as a result of comprehensive evaluation of layer separation, dispersibility, viscosity, wafer cleaning time after sawing, wafer warping after sawing, a in Formula 1 is 7 to 20, and b in Formula 2 is 39 to 52, and c of the formula (3) was evaluated to be significantly superior to Examples 1 to 3 of 39 to 41 compared to Comparative Examples 1 and 2.

Β. Examples 4 to 6 and Comparative Examples 3 and 4: Evaluation of composition ratio of mineral oil

In the cutting oil composition comprising the mineral oil represented by the formula (1) to (3), after fixing the a value of the formula (1), the b value of the formula (2), the c value of the formula (3), the evaluation for determining the numerical range of the mineral oil content Proceed to Table 2 below.

Example 4 Example 5 Example 6 Comparative Example 3 Comparative Example 4 a 18 18 18 18 18 b 39 39 39 39 39 c 43 43 43 43 43 Oil content wt% 90 70 80 60 99 Bentonite clay content wt% One One One One One Glycerine tri oleate content wt% 9 29 19 39 0 Coolant + SiC = 1: 1 Separation No layer separation No layer separation No layer separation With delamination (2mm) With delamination (5mm) Dispersibility Good Good Good Good usually Viscosity (mPa.s@25℃) 100 132 115 158 88

As shown in Table 2 above, as a result of comprehensive evaluation of layer separation, dispersibility, and viscosity, Examples 1 to 3, which are 70 to 90% by weight of mineral oil, were evaluated to be remarkably superior to Comparative Examples 3 and 4.

C. Example  7, 8 and Comparative example  5 to 7: evaluation of the composition ratio of bentonite

In the cutting oil composition comprising the mineral oil represented by the formula (1) to formula (3), after fixing the a value of the formula (1), the b value of the formula (2), the c value of the formula (3), evaluation for determining the numerical range of the bentonite content It is shown in Table 3.

Example 7 Example 8 Comparative Example 5 Comparative Example 6 Comparative Example 7 a 18 18 18 18 18 b 39 39 39 39 39 c 43 43 43 43 43 Oil content wt% 90.0 89 91.0 90.5 86 Bentonite clay content wt% 1.0 2.0 0.0 0.5 5.0 Glycerine tri oleate content wt% 9 9 9 9 9 Coolant + SiC = 1: 1 Separation No layer separation No layer separation With delamination (7.5mm) With delamination (2.0mm) No layer separation Dispersibility Good Good Bad usually Good Viscosity (mPa.s@25℃) 100 140 45 69 296

As shown in Table 3 above, as a result of comprehensive evaluation of layer separation, dispersibility, and viscosity, Examples 7 and 8 having a bentonite content of 1 to 2% by weight were evaluated to be remarkably superior to Comparative Examples 5 to 7. .

D. Example  9 to 11 and Comparative example  8, 9: glycerin Trioleate  Subsidy cost evaluation

In the cutting oil composition comprising the mineral oil represented by Formula 1 to Formula 3, after fixing the a value of Formula 1, the b value of Formula 2, the c value of Formula 3, the value of the glycerin trioleate content The evaluation to determine the range was carried out and listed in Table 4.

Example 9 Example 10 Example 11 Comparative Example 8 Comparative Example 9 a 18 18 18 18 18 b 39 39 39 39 39 c 43 43 43 43 43 Oil content wt% 90.0 79.0 84.0 94.0 98.9 Bentonite clay content wt% 1.0 1.0 1.0 1.0 1.0 Glycerine tri oleate content wt% 9.0 20.0 15.0 5.0 0.1 Coolant + SiC = 1: 1 Separation No layer separation No layer separation No layer separation No layer separation With delamination (2.0mm) Dispersibility Good Good Good usually usually Viscosity (mPa.s@25℃) 100 119 108 89 74

As shown in Table 4 above, as a result of comprehensive evaluation of layer separation, dispersibility, and viscosity, Examples 9 to 11 having a glycerin trioleate content of 9 to 20% by weight were compared to Comparative Examples 8 and 9. It was evaluated to be remarkably superior in comparison.

From these results, 70 to 90% by weight of mineral oil, 1 to 2% by weight of bentonite, glycerin, wherein a in Formula 1 is 7 to 20, b in Formula 2 is 39 to 52, and c in Formula 3 is 39 to 41. In the case of 9-20% by weight of triglyceride (Glycerine trioleate), it was found to be remarkably superior when comprehensively evaluating layer separation, dispersibility, viscosity, wafer cleaning time after sawing, and wafer warping after sawing.

All simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (7)

Cutting oil composition comprising a mineral oil represented by the following formula (1), (2) and (3). [Formula 1] R1- (CnH2n-4) a-R2 [Formula 2] R3- (CnH2n-2) b-R4 [Formula 3] R5- (CnH2n) c-R6 N in the formula is 5 or 6, and R1, R2, R3, R4, R5 and R6 are each H or OH. The cutting oil composition of claim 1, wherein a is 7 to 20, b is 39 to 52, and c is 39 to 41. The cutting oil composition of claim 1, further comprising a thickener and a dispersant. 4. The cutting oil composition of claim 3, wherein the thickener is bentonite clay and the dispersant is glycerin trioleate. The cutting oil composition according to claim 4, which is 65 to 93% by weight of mineral oil, 0.7 to 3% by weight of bentonite, and 5 to 35% by weight of glycerin trioleate. 6. The cutting oil composition according to claim 5, which is 70 to 90% by weight of mineral oil, 1 to 2% by weight of bentonite, and 9 to 29% by weight of glycerin trioleate. The cutting method using the cutting oil composition of any one of Claims 1-6.