KR101847266B1 - Polishing composition, and polishing method using the same - Google Patents

Abstract

A polishing composition which is excellent in dissolution stability and enables polishing at a high polishing rate, and a polishing method using the polishing composition.
(B) component: a fatty acid having a carbon number of 10 or more and 22 or less, and (C) a component: a nonionic surfactant, Wherein the abrasive composition (A) has an abrasive grain size of more than 1.0 占 퐉 and not more than 10.0 占 퐉, and the component (C) Wherein the molar ratio of the component (D) / (B) to the component (B) is from 45/55 to 90/10, and [2] A polishing method for polishing a substrate comprising at least one material selected from silicon, gallium nitride and aluminum nitride using the polishing composition according to the above [1].

Description

TECHNICAL FIELD [0001] The present invention relates to a polishing composition, and a polishing method using the polishing composition.

The present invention relates to a polishing composition used for polishing a substrate material having a high hardness and a high hardness, and a polishing method using the polishing composition.

A sapphire substrate, a silicon carbide (SiC) substrate, a gallium nitride (GaN) substrate, an aluminum nitride (AlN) substrate, or the like used for manufacturing a light emitting diode (hereinafter simply referred to as an LED) It is also a substrate material having a high hardness.

Sapphire substrates have recently been widely used as growth substrates for GaN epitaxial layers for LEDs. The use of smartphones and tablet terminals as cover glasses is also expanding.

The silicon carbide substrate (hereinafter simply referred to as "SiC") substrate is excellent in heat resistance and withstand voltage, and is used for electric / hybrid vehicles, solar power generation, information devices, It is progressing.

However, since new materials such as sapphire and SiC are difficult to manufacture, have a high hardness and are highly heat-shrinkable, there are many difficulties in wafer processing techniques. Therefore, there is a problem that material cost and processing cost are increased.

The sapphire substrate is taken out as a single crystal ingot by, for example, the CZ method, cut into a cylindrical shape so as to obtain a desired crystal face, and cut into a wafer shape by wire sawing. The wafer-shaped sapphire substrate is polished on both sides with a slurry including, for example, a GC abrasive using a double-side polishing machine and planarized. Since the polishing scratches and the damaged layer remain on the sapphire substrate after the GC abrasive polishing, these must be removed.

As this removal step, for example, a single-sided polishing machine is used to drop a slurry of diamond abrasive grains on a platen, and a lapping step (hereinafter simply referred to as a " lapping step " Is performed.

Further, in applications where a sapphire substrate is used as a growth substrate for a GaN epitaxial layer for LEDs, a chemical mechanical polishing process for further reducing surface roughness with a slurry containing colloidal silica is also performed.

As a slurry of diamond abrasive grains to be used in the lapping process, there is provided a polishing composition which uniformly disperses hydrophilic abrasive grains (such as diamond) in a solvent of hydrocarbon oil by using a nitrogen-containing surfactant and a carboxylic acid polymer (Patent Document 1). However, this polishing composition is problematic in that the base of the slurry is a hydrocarbon oil, and a cleaning agent is required for cleaning the surface of the polishing plate after the polishing operation and the polishing object, thereby increasing the cleaning operation time.

In the case where water or a water-soluble solvent is used as the base of the slurry, the above-mentioned problem of the cleaning property is improved. However, it has the disadvantage that the lubricity becomes worse as compared with the slurry of the oil base, and the finish such as the surface roughness of the object to be polished deteriorates.

In order to compensate for the drawbacks of such a water-based slurry, a composition for texturing containing a fatty acid having 10 to 22 carbon atoms is known (Patent Document 2). In Patent Document 2, it is disclosed that the addition of the above fatty acid improves the lubricity of the composition and achieves good surface finish.

However, since the fatty acid has a low solubility, it is preferred to use an alkylene glycol monoalkyl ether, a polyhydric alcohol, and a polyhydric alcohol (hereinafter, simply referred to as " polyol ") for the purpose of stably dissolving the fatty acid in the composition At least one kind of polymer is added.

Japanese Patent No. 3973355 Specification Japanese Patent No. 4015945 Specification

In the composition described in Reference Document 2, good surface finish is obtained, but it is not yet sufficient to obtain excellent dissolution stability and polishing at a high polishing rate, and there is still room for improvement.

An object of the present invention is to provide a polishing composition which is excellent in dissolution stability and enables polishing at a high polishing rate, and a polishing method using the polishing composition.

As a result of intensive studies, the inventors of the present invention have found that a polishing composition comprising a fatty acid having a specific number of carbon atoms, a nonionic surfactant, and an organic amine compound in a dispersion medium solves the above problems. The fatty acid and the organic amine compound form a salt in the polishing composition and the solubility of the salt is increased by the nonionic surfactant and the fatty acid can be stably dissolved. Thus, it is considered that in polishing, it is possible to suppress the precipitation of the fatty acid in the polishing composition on the surface of the polishing pad, thereby promoting uniform contact between the polishing composition and the polishing pad. As a result, it is thought that the effect of enhancing the lubricity by the fatty acid contained in the polishing composition and the effect of enhancing the dissolution stability of the fatty acid by the nonionic surfactant and the organic amine compound act synergistically, do.

The present invention is based on the above knowledge.

That is, the present invention provides the following [1] to [13].

(B) component: a fatty acid having a carbon number of 10 or more and 22 or less, and (C) a component: a nonionic interface Wherein the abrasive composition (A) has an abrasive grain size of more than 1.0 占 퐉 and not more than 10.0 占 퐉, and the component (C) Wherein the molar ratio of the component (D) to the component (B) is from 45/55 to 90/10, and the content of the component (B) is from 0.30 to 10 mass%.

[2] The positive resist composition as described in [1], wherein the content of the component (A) is 0.03 to 3.0 mass%, the content of the component (B) is 0.10 to 10 mass%, the content of the component (D) is 1.0 to 20 mass% Is from 60 to 98% by mass based on the total amount of the polishing composition.

[3] The polishing composition according to [1] or [2], wherein the abrasive grains are diamond.

[4] The polishing composition according to any one of [1] to [3], wherein the fatty acid is at least one selected from lauric acid and oleic acid.

[5] The polishing composition according to any one of [1] to [4], wherein the nonionic surfactant is at least one selected from polyetheramine and sorbitan ester-ethylene oxide adducts.

[6] The composition according to [1], wherein the nonionic surfactant is at least one selected from polyoxyethylene laurylamine, polyoxyethylene urea alkylamine, polyoxyethylene sorbitan monolaurate, and polyoxyethylene sorbitan monooleate. The polishing composition according to any one of [1] to [5].

[7] The polishing composition according to any one of [1] to [6], wherein the organic amine compound is an alkanolamine.

[8] The polishing composition according to any one of [1] to [7], wherein the organic amine compound is triethanolamine.

[9] The polishing composition according to any one of [1] to [8], wherein the dispersion medium contains at least one selected from ethylene glycol, diethylene glycol, and propylene glycol.

[10] The method according to any one of [1] to [9] above, wherein the dispersion medium is a mixture of a water-soluble organic solvent and water, and the mass ratio of the water-soluble organic solvent to water (water-soluble organic solvent / water) is 30/70 to 95/5. 0.0 > 1, < / RTI >

[11] The polishing composition according to any one of [1] to [10], wherein the dispersion medium is a mixture of water and at least one selected from ethylene glycol, diethylene glycol, and propylene glycol.

[12] A polishing method for polishing a substrate comprising at least one material selected from the group consisting of sapphire, silicon carbide, gallium nitride and aluminum nitride using the polishing composition according to any one of [1] to [11].

[13] The polishing method according to [12], wherein the substrate is a substrate for a light-emitting diode including sapphire.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a polishing composition which is excellent in dissolution stability and capable of polishing at a high polishing rate in polishing a hard and highly-hard material, and a polishing method using the polishing composition have.

<Polishing composition>

(A): at least one abrasive grain selected from diamond, boron nitride, boron carbide, and silicon carbide; (B) component: a fatty acid having a carbon number of 10 or more and 22 or less; (C) A polishing composition comprising a nonionic surfactant, a component (D): an organic amine compound, and a component (E): a dispersion medium, wherein the abrasive composition (A) has an abrasive grain size of more than 1.0 탆 and not more than 10.0 탆 (D) / (B)] of the component (D) to the component (B) is from 45/55 to 90/10, and the content of the component (C) is from 0.30 to 10 mass%.

In the present specification, "dissolution stability" means that the fatty acid is stably dissolved.

[Component (A): abrasive]

The polishing composition of the present invention contains at least one abrasive (hereinafter, simply referred to as "component (A)") selected from the component (A): diamond, boron nitride, boron carbide and silicon carbide.

The diamond used as the abrasive grains is not particularly limited, and for example, natural diamond and artificial diamond are preferable.

The method of producing artificial diamonds is not particularly limited. The artificial diamond may be either a single crystal diamond, a polycrystalline diamond, or a mixture of a single crystal diamond and a polycrystalline diamond.

Boron nitride, boron carbide, and silicon carbide used as the abrasive grains are not particularly limited, but industrially synthesized fine particles or powders can be used.

The abrasive grains are at least one selected from diamond, boron nitride, boron carbide, and silicon carbide, and preferably at least one selected from diamond and boron carbide, more preferably diamond.

These may be used singly or in combination of two or more kinds.

The average particle diameter (median diameter (D50), volume basis) of the abrasive grains is more than 1.0 占 퐉 and not more than 10.0 占 퐉, preferably 1.5 to 8.0 占 퐉, more preferably 2.0 to 6.0 占 퐉. When the average grain size of the abrasive grains exceeds 1.0 탆, a sufficient polishing rate is obtained. When the average grain size is 10.0 탆 or less, occurrence of polishing scratches on the surface of the abrasive substrate to be polished can be suppressed. The average particle diameter of the abrasive grains is measured by the laser diffraction scattering method described in Examples.

The content of the component (A) is preferably 0.03 to 3.0% by mass, more preferably 0.06 to 1.5% by mass, still more preferably 0.09 to 1.0% by mass, still more preferably 0.15% 0.5% by mass. When the content of the component (A) is 0.03 mass% or more, a sufficient polishing rate can be obtained. When the content of the component (A) is 3.0 mass% or less, the amount of scratches (scratch) caused by agglomeration of the abrasive grains is suppressed, The economic benefit is increased.

There is no particular limitation on the method of adding to the abrasive composition containing the abrasive grains. The abrasive grains may be directly added to the dispersion medium of component (E) and mixed. Or the abrasive grains may be mixed with water, preferably deionized water, and then mixed with the dispersion medium of component (E). The mixing method is not particularly limited, but a magnetic stirrer, a three-one motor, an ultrasonic homogenizer and the like can be used.

[Component (B): a fatty acid having 10 or more carbon atoms and 22 or less carbon atoms]

The polishing composition of the present invention contains component (B): a fatty acid having 10 or more carbon atoms and 10 or less carbon atoms (hereinafter, simply referred to as "component (B)").

Fatty acid, which is a component (B), is used to improve lubricity.

The number of carbon atoms of the fatty acid used in the present invention is 10 or more, preferably 12 or more from the viewpoint of lubricity and is 22 or less, preferably 20 or less, more preferably 18 or less . When the number of carbon atoms of the fatty acid is 10 or more, lipophilicity can be improved while suppressing metal corrosion. Thus, lubricity can be improved. When the number of carbon atoms in the fatty acid is 22 or less, when the dispersion medium contains a water-soluble organic solvent such as ethylene glycol And therefore, good dissolution stability can be obtained. The fatty acid may be linear or branched.

Examples of the fatty acid include saturated fatty acids such as capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid; And unsaturated fatty acids such as oleic acid, linoleic acid and erucic acid. In the present invention, among these, from the viewpoint that the surface tension of the polishing composition is lowered, the permeability between the substrate and the surface of the substrate is improved, and the entire polishing composition contributes to the polishing effectively, it is preferably selected from lauric acid and oleic acid Or more, and more preferably lauric acid. These may be used singly or in combination of two or more kinds. However, as the fatty acid of component (B), these metal salts are not included.

The content of the component (B) is preferably from 0.10 to 10 mass%, more preferably from 0.50 to 8.0 mass%, still more preferably from 1.0 to 6.0 mass%, still more preferably from 3.0 to 3.0 mass% 6.0% by mass. When the content of the component (B) is 0.10% by mass or more, an acceleration improving effect of a sufficient polishing rate is obtained. When the content is 10% by mass or less, the effect of accelerating the polishing rate is obtained, The effect of the dissolution stability of the polishing composition can be improved.

[Component (C): nonionic surfactant]

The polishing composition of the present invention contains component (C): nonionic surfactant (hereinafter, simply referred to as "component (C)"). The nonionic surfactant as the component (C) is used for improving the dissolution stability of the fatty acid of the component (B).

When the nonionic surfactant is contained in the polishing composition of the present invention, it is considered that the stability of the dissolution of the fatty acid can be improved without inhibiting the interaction between the fatty acid and the organic amine compound present as a salt in the polishing composition.

The nonionic surfactant is preferably a nonionic surfactant having a polyoxyalkylene group, more preferably a nonionic surfactant having a polyoxyalkylene group and a fatty acid residue, from the viewpoint of improving the dissolution stability of a fatty acid .

The oxyalkylene group constituting the polyoxyalkylene group is preferably at least one selected from an oxyethylene group and an oxypropylene group, and more preferably an oxyethylene group. The average addition mole number of the oxyalkylene group is preferably 2 to 30, more preferably 4 to 20.

The number of carbon atoms in the fatty acid residue is preferably 10 or more, more preferably 12 or more, still more preferably 14 or more, and preferably 22 or less, more preferably 20 or less, still more preferably 18 or less .

The nonionic surfactant is preferably at least one selected from a polyetheramine and a sorbitan ester-ethylene oxide adduct, more preferably a sorbitan ester-ethylene oxide adduct, from the viewpoint of improving the dissolution stability of the fatty acid The seed adduct is water.

Examples of the polyetheramine include polyoxyethylene laurylamine, polyoxyethylene polyoxypropylene laurylamine, polyoxyethylene alkyl (palm) amine, polyoxyethylene stearylamine, polyoxyethylene oleylamine, polyoxyethylene oleyl amine And polyoxyalkylene aliphatic amines having 10 to 22 carbon atoms, such as saturated or unsaturated, linear or branched hydrocarbon groups.

The hydrocarbon group constituting the polyoxyalkylene aliphatic amine is preferably 12 or more, more preferably 14 or more, and preferably 20 or less, and furthermore preferably 18 or less, from the viewpoint of improving the polishing rate. The average addition mole number of the oxyalkylene group constituting the polyoxyalkylene aliphatic amine is preferably 2 to 30, more preferably 4 to 20, still more preferably 4 to 10.

Among them, at least one selected from polyoxyethylene laurylamine, polyoxyethylene alkyl (palm) amine, polyoxyethylene oleylamine, and polyoxyethylene urea alkylamine is preferable from the viewpoint of improving the polishing rate, More preferably at least one member selected from polyoxyethylene lauryl amine, polyoxyethylene alkyl (palm) amine, and polyoxyethylene urea alkylamine, more preferably polyoxyethylene laurylamine and polyoxyethylene urea alkylamine And polyoxyethylene urea alkylamine is more preferable.

The sorbitan ester-ethylene oxide adduct has a fatty acid residue, and the number of carbon atoms of the fatty acid residue is preferably 10 or more, more preferably 12 or more, further preferably 14 or more, and preferably 20 Or less, more preferably 18 or less. The average addition mole number of the oxyalkylene group constituting the sorbitan ester-ethylene oxide adduct is preferably 2 to 30, more preferably 8 to 25, still more preferably 10 to 25.

Examples of sorbitan ester-ethylene oxide adducts include polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene And sorbitan trioleate. From the viewpoint of improving the polishing rate, at least one selected from polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan monooleate is preferable.

As the nonionic surfactant, from the viewpoint of the improvement of the polishing rate, a nonionic surfactant is preferably selected from the group consisting of polyoxyethylene laurylamine, polyoxyethylene urea alkylamine, polyoxyethylene sorbitan monolaurate, and polyoxyethylene sorbitan monooleate Or more is preferable, and at least one selected from polyoxyethylene urea alkylamine and polyoxyethylene sorbitan monooleate is more preferable, and polyoxyethylene urea alkylamine is more preferable.

The content of the component (C) is 0.30 to 10 mass%, preferably 0.50 to 8.0 mass%, more preferably 0.70 to 7.0 mass%, and still more preferably 1.0 to 5.0 mass% with respect to the total amount of the polishing composition. When the content of the component (C) is 0.30 mass% or more, improvement of the dissolution stability and acceleration of the polishing rate are attained. When the content of the component (C) is 10 mass% or less, the effect of accelerating the polishing rate is enhanced.

[Component (D): organic amine compound]

The polishing composition of the present invention contains component (D): organic amine compound (hereinafter, simply referred to as "component (D)"). When the organic amine compound as the component (D) is used in combination with the fatty acid as the component (B), the effect of accelerating the polishing rate can be obtained.

The organic amine compound is preferably a low molecular weight organic amine compound having a molecular weight of 200 or less, and examples thereof include alkanolamines such as monoethanolamine, diethanolamine and triethanolamine; Alkylenediamines such as ethylenediamine and propanediamine; And polyalkylene polyamines such as diethylenetriamine, triethylenetetramine and the like. The organic amine compound is preferably an alkanolamine, more preferably at least one selected from diethanolamine and triethanolamine, more preferably triethanolamine. These may be used singly or in combination of two or more kinds. However, as the organic amine compound of component (D), salts thereof are not included.

The content of the component (D) is preferably 1.0 to 20 mass%, more preferably 2.0 to 15 mass%, further preferably 2.0 to 10 mass%, still more preferably 3.0 to 20 mass% 5.0% by mass. When the content of the component (D) is 1.0% by mass or more, improvement of the dissolution stability and acceleration of the polishing rate are attained. When the content is 20% by mass or less, the effect of accelerating the polishing rate is enhanced.

The molar ratio [(D) / (B)] of the component (D) to the component (B) in the polishing composition of the present invention is 45/55 to 90/10, preferably 50/50 to 90/10, More preferably 50/50 to 80/20, more preferably 50/50 to 75/25, still more preferably 50/50 to 70/30, even more preferably 50/50 to 60/25, 40. When the molar ratio [(D) / (B)] is 45/55 or more, the fatty acid is stably dissolved at room temperature. When the molar ratio [(D) / (B)] is 90/10 or less, An effect of excellent economical efficiency and practicality can be obtained.

[Component (E): dispersion medium]

The polishing composition of the present invention contains component (E): dispersion medium (hereinafter, simply referred to as "component (E)"). The dispersion medium preferably contains a water-soluble organic solvent.

The water-soluble organic solvent preferably has a solubility in water at 20 캜 of at least 10 g / 100 ml, more preferably at least 20 g / 100 ml, more preferably at least 30 g / 100 ml, even more preferably at least 40 g / , More preferably at least 50 g / 100 ml, and it is more preferable to uniformly mix with water at an arbitrary ratio.

As the water-soluble organic solvent, glycols are preferable from the viewpoints of flammability and environmental load. Specific examples of the glycols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol and polypropylene glycol. These may be used singly or in combination of two or more in an arbitrary ratio.

The water-soluble organic solvent is preferably at least one selected from the group consisting of ethylene glycol, diethylene glycol, and propylene glycol, more preferably ethylene glycol, from the viewpoints of flammability and environmental load, viscosity, and dissolution stability. By using these water-soluble organic solvents, there is no volatility or characteristic odor, so that the polishing composition of the present invention can be obtained without deteriorating the working environment. Further, when the substrate is polished using a polishing composition containing these water-soluble organic solvents, a local exhaust system and a mask for organic work are unnecessary, and handling is facilitated.

The content of the water-soluble organic solvent in the component (E) is preferably 30 mass% or more, more preferably 50 mass% or more, further preferably 60 mass% or more, and even more preferably 70 mass% Preferably 95 mass% or less, more preferably 90 mass% or less, further preferably 85 mass% or less, and even more preferably 80 mass% or less. When the content of the water-soluble organic solvent in the component (E) is 30 mass% or more, the effect of accelerating the polishing rate can be obtained. When the content of the water-soluble organic solvent is 95 mass% or less, the polishing composition stably stays on the surface, The machining efficiency is improved.

The content of the component (E) is preferably 60 mass% or more, more preferably 70 mass% or more, further preferably 80 mass% or more, and preferably 98 mass% or less, And more preferably 95 mass% or less. When the content of the component (E) is 60 mass% or more, the viscosity of the polishing composition is lowered and the polishing composition stably stays on the surface of the polishing pad to improve the efficiency of the polishing process. When the content is 98 mass% or less, .

The content of the water-soluble organic solvent is preferably 40 mass% or more, more preferably 50 mass% or more, further preferably 60 mass% or more, and preferably 86 mass% or less, More preferably 80% by mass or less, further preferably 78% by mass or less, still more preferably 75% by mass or less. When the content of the water-soluble organic solvent is 40 mass% or more, good dissolution stability can be obtained. When the content is 86 mass% or less, a high polishing rate can be obtained.

The component (E) may further contain water from the viewpoint of enhancing the dispersibility of the abrasive grain, and is preferably a mixture of water-soluble organic solvent and water, more preferably selected from ethylene glycol, diethylene glycol, and propylene glycol And water, more preferably a mixture of ethylene glycol and water.

The mass ratio of the water-soluble organic solvent to water (water-soluble organic solvent / water) is preferably from 30/70 to 95/5, more preferably from 30/70 to 95/5, from the viewpoint of enhancing the dispersibility of the abrasive grains and from the viewpoint of improving the dissolution stability and obtaining a high polishing rate. More preferably 50/50 to 90/10, further preferably 60/40 to 85/15, and even more preferably 70/30 to 80/20.

The content of water is preferably less than 60% by mass, more preferably less than 40% by mass, further preferably less than 20% by mass, and preferably 3.0% by mass based on the whole amount of the polishing composition from the viewpoint of dissolution stability % Or more, and more preferably 5.0 mass% or more. When the content of water is less than 60% by mass, the polishing rate tends to be slightly lowered, but a practically sufficient polishing rate can be obtained. When the content of water is 3.0% by mass or more and less than 40% by mass, a higher polishing rate can be obtained.

Water used in the present invention is preferably water that has passed through a filter to avoid incorporation of foreign matter into the polishing composition, and pure water is more preferable. When preparing the polishing composition of the present invention, it is possible to prepare an abrasive dispersion water in which abrasive grains are first dispersed in water, and mixing the dispersion water with a water-soluble organic solvent so as to have a desired abrasive grain concentration.

The polishing composition of the present invention may contain, in addition to the components (A) to (E), other components as long as the effect of the present invention is not impaired. For example, an additive (pH adjuster) for further adjusting the pH may be contained. As the pH adjuster, known acids and basic substances can be used. As the acid, for example, inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, and phosphoric acid can be used. Of these, hydrochloric acid and sulfuric acid are preferred. As the basic substance, ammonia water, sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide and the like can be used. Of these, sodium hydroxide and potassium hydroxide are preferred.

As other additives, a disinfectant for inhibiting the growth of microorganisms in the polishing composition, a lubricant for improving lubricity, a thickener for increasing viscosity, a defoaming agent, and the like may be added within the range not hindering the effect of the present invention.

When a defoaming agent is added, a polyalkylene glycol derivative is preferable, and its content is preferably from 0.10 to 3.0 mass%.

It is preferable that the polishing composition is produced at a work place where positive pressure is made with air removed from the air by a clean room or a filter so that impurities and other foreign matter do not enter. This is because foreign matter scratched the substrate when polished.

The viscosity of the polishing composition of the present invention at 22 캜 is preferably 5 to 35 mPa · s, and more preferably 10 to 30 mPa · s. When the viscosity is 5 mPa · s or more, the effect of accelerating the polishing rate can be obtained. When the viscosity is 35 mPa · s or less, the polishing composition stably stays on the surface of the polishing pad, and the efficiency of polishing is improved.

The viscosity at 22 占 폚 is measured by the method described in the examples.

The pH of the polishing composition of the present invention at 25 캜 is preferably 7 to 9, more preferably 7 to 8. By setting the pH to 7 to 9, deterioration of the substrate can be suppressed.

The pH at 25 占 폚 is measured by the method described in the examples.

[Method of producing polishing composition]

The method for producing the polishing composition of the present invention is not particularly limited, but the organic amine compound of component (D) is added while stirring the dispersion medium of component (E) in a beaker or tank. For stirring, a magnetic stirrer, a three-one motor and the like can be used.

Subsequently, the nonionic surfactant of component (C) is added. After the component (C) and the component (D) are uniformly mixed, the fatty acid of the component (B) is added. And stirring is performed until the component (B) is completely dissolved. Finally, the abrasive grains of the component (A) are added, and the dispersion treatment is carried out so as to be uniform. For the dispersion treatment, a magnetic stirrer, a three-one motor, an ultrasonic homogenizer, or the like can be used.

The polishing composition of the present invention is prepared by using two kits of the abrasive grains of the component (A) as the kit 1 and the dispersion containing the component (B), the component (C), the component (D) This product can be transported and stored. The kits 1 and 2 may be mixed immediately before polishing and supplied to a polishing machine.

The abrasive grains of the component (A) may be included in the kit 1 as abrasive grains dispersed in a certain amount of water. In this case, when used for polishing, the kits 1 and 2 may be mixed and supplied to a polishing machine, or the kit 1 containing abrasive dispersion water and the kit 2 containing the dispersion may be separately supplied onto a polishing platen. It is preferable that the polishing machine in this case is provided with a correction ring.

<Polishing method>

The polishing method of the present invention is a method of polishing a high hardness and high hardness material substrate comprising at least one material selected from the group consisting of sapphire, silicon carbide, gallium nitride, and aluminum nitride using the polishing composition.

Among these substrates, a substrate for a light emitting diode including sapphire is preferable in that a high polishing rate can be obtained.

As a device used in the polishing method of the present invention, there can be mentioned a one-side and two-side polishing machine. For example, as a single-side polishing machine, there is known a single-side polishing machine including a rotary table on which a base plate made of a metal or a metal-containing resin is fixed, a substrate holding portion (e.g., a ceramic plate) on which a substrate is fixed, And a pressing portion having a mechanism for pressing the substrate against the polishing surface and rotating the substrate. In this case, while supplying the polishing composition onto a platen made of a metal or a metal-containing resin, the substrate fixed to the substrate holding portion is pressed against the platen by a predetermined polishing load to perform polishing.

As the polishing load in the polishing method of the present invention, for example, 100 to 500 g / cm 2, a high polishing rate can be obtained. As the rotation speed of the surface plate and the substrate holding and supporting portion, for example, 30 to 120 rpm, a high polishing rate is obtained.

In the polishing method of the present invention, a high polishing rate can be obtained by setting the supply amount of the polishing composition to, for example, 0.1 to 5 ml / min. As the metal constituting the base, iron, tin, copper and the like can be used. As the resin constituting the surface plate, an epoxy resin, a melamine resin, or the like can be used.

The polishing method of the present invention can obtain a high polishing rate by using the polishing composition in a lapping process of polishing a mirror surface of a hard and highly hard material.

[Example]

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited thereto at all.

[Average particle size of abrasive grains (median diameter (D50), volume basis)]

The average particle diameter of the abrasive grains was measured by using a laser diffraction scattering type particle size distribution analyzer (Microtrack MT3000II, manufactured by Nikkiso Co., Ltd.), and the volume particle size distribution was measured. From the measurement results, Was found to be 50%.

0.1 g of abrasive grains were weighed into a sample bottle, and 9.9 g of pure water was added thereto to prepare an abrasive grain dispersion water of 1 mass%. The abrasive dispersion water was dispersed for 3 minutes using an ultrasonic homogenizer &quot; US-300T &quot; (model name, manufactured by Nippon Seiki Seisakusho Co., Ltd.), and then the measurement was carried out with the particle size distribution measuring apparatus. The measurement conditions are as follows.

Particle permeability: permeation

Particle refractive index: 2.41 (diamond)

Particle shape: Non-spherical

Solvent: water

Solvent refractive index: 1.333

Calculation mode: MT3000II

[Polishing test]

A polishing test of a sapphire substrate was carried out using the polishing compositions obtained in Examples and Comparative Examples. The conditions of the abrasion test are shown below.

Grinding machine: "SLM-140" (product name, Fujikoshi Kaikokyo Co., Ltd.)

Polishing load: 150 g / cm &lt;

Platen rotational speed: 61 rpm

Number of revolutions of pressing part: 63 rpm

Revision Ring Rotation Speed: 63 rpm

Supply amount of polishing composition: 0.33 ml / min

Plate: 400 mm in diameter, copper plate

Processing time: 20min

Substrate: 4-inch sapphire substrate, thickness about 700 μm

[Polishing rate]

Using a dial gauge, the thickness of the sapphire substrate before and after polishing was measured, and the polishing rate was calculated by the following formula (1).

Polishing rate (μm / min) = {[(thickness of sapphire substrate before polishing) (μm)] - [thickness of sapphire substrate after polishing (μm)

[Evaluation of dissolution stability]

The mixed solution obtained in the Examples and Comparative Examples was used as a sample for dissolution stability evaluation. The sample for evaluation was kept at room temperature (25 캜) and ice water at 0 캜 for 1 hour, and then observed with naked eyes to determine the presence or absence of precipitates And evaluated by evaluation criteria. The results are shown in Tables 1 to 7.

(Evaluation standard)

A: There was no precipitate at all at room temperature and 0 ° C.

B: There was no precipitate at room temperature, but there was precipitate at 0 ° C.

[Viscosity]

The viscosity of the mixed solution obtained in the examples and comparative examples was determined as a sample for measurement.

Vibratory Viscometer: Biscomate VM-100A-L (model name, manufactured by Yamaichi Denki K.K.)

Measuring temperature: 22 ° C

[pH]

The pH of the mixed solution was measured using the mixed solution obtained in Examples and Comparative Examples as a measurement sample.

pH meter: D-13 (model name, manufactured by Horiba Seisakusho Co., Ltd.)

Measuring temperature: 25 ° C

Examples 1 to 18, Comparative Examples 1 to 7, and Reference Example 1

A polishing composition was prepared with the composition shown in Tables 1 to 7. The composition of each component is% by mass with respect to the total amount of the polishing composition, and the respective components are as follows. In addition, water was ion-exchanged water.

Hereinafter, a method for preparing a polishing composition will be described.

First, the components (E), (D) and (C) were weighed in this order into a beaker, and stirred and mixed with a magnetic stirrer until uniform. Subsequently, component (B) was added and stirred until dissolved to obtain a mixed solution. An abrasive component (A) was further added to the mixed solution to obtain a polishing composition.

The dissolution stability, viscosity and pH were evaluated using the mixture obtained above. Evaluation of dissolution stability and measurement of viscosity and pH obtained using the mixed solution were regarded as evaluation of dissolution stability of the polishing composition and measurement of viscosity and pH.

The polishing test was carried out using the polishing composition obtained above.

[Component (A)] [

Diamond: average particle diameter (median diameter, volume basis) D50 = 3.65 占 퐉, manufactured by Beijing Grish Co. (grade PCD G3.5)

[Component (B)] [

Fatty acid: Lauric acid (trade name: NAA (registered trademark) -122, manufactured by Nichiyu Corporation)

[Component (C)] [

- Polyoxyethylene urea alkylamine (trade name: Nymin (registered trademark) T2-210, manufactured by Nichiyu Corporation)

Polyoxyethylene laurylamine (trade name: NIFMIN (registered trademark) L-207, manufactured by Nichiyu Corporation)

Polyoxyethylene sorbitan monolaurate (trade name: Leodospor TW-L120, manufactured by Kao Corporation)

Polyoxyethylene sorbitan monooleate (trade name: Nonion OT-221, manufactured by Nichiyu Corporation)

[Component (D)] [

· Triethanolamine (manufactured by Sanwa-Yushi Chemical Co., Ltd.)

[Component (E)] [

(Water-soluble organic solvent)

Ethylene glycol (manufactured by Yamaichikagakukogyo Co., Ltd.)

Diethylene glycol (manufactured by Kanto Kagaku Co., Ltd.)

Propylene glycol (manufactured by ADEKA Corporation)

[Other components]

(Antifoaming agent)

· Polyalkylene glycol derivative (trade name: DISHOTE (registered trademark) CC-118, manufactured by Nichiyu Co., Ltd.)

(Fatty acid amide)

Lauric acid diethanolamide (trade name: Starhome (registered trademark) DL, manufactured by Nichiyu)

Oleic acid diethanolamide (manufactured by Nichiyu Corporation, trade name: Star Home (registered trademark) DO)

· Coconut oil fatty acid diethanolamide (trade name: Star Home (registered trademark) F manufactured by Nichiyu Corporation)

(Anionic surfactant)

-Polyoxyethylene-alkyl ether-sulfuric acid ester-triethanolamine salt [manufactured by Nichiyu Corporation, trade name: PERSOFT (registered trademark) EL-T]

It can be seen that Examples 1 to 18 are superior in dissolution stability and have a higher polishing rate as compared with Comparative Examples 1 to 7. This is believed to be because fatty acids can be stably dissolved by adding a nonionic surfactant and an organic amine compound.

Comparative Example 4, Comparative Example 5, and Comparative Example 6 were obtained by adding 5% by mass of lauric acid diethanolamide, oleic acid diethanolamide, and palm oil fatty acid diethanolamide, respectively, instead of the fatty acid and organic amine compounds. In comparison with Examples 1 to 18, the polishing rate was poor. In addition, in Comparative Example 4, it was found that it did not have dissolution stability.

These results indicate that the addition of fatty acid and organic amine compound contributes greatly to the improvement of the polishing rate. In Examples 1 to 18, the affinity of the fatty acid for the plate was increased because the amine salt was formed by the addition of the fatty acid and the organic amine compound. As a result, the lubricity was improved more than the fatty acid amide and the polishing rate was improved .

Comparative Example 1 is a polishing composition that does not contain a surfactant, but the polishing rate is lower than those of Examples 1 to 18. In addition, it appeared that it did not have dissolution stability.

In Comparative Example 3, an anionic surfactant was used. As compared with Examples 1 to 18, the polishing rate was poor. It is considered that in the polishing composition, the fatty acid and the organic amine compound are present as a salt, and the solubility thereof is enhanced by the nonionic surfactant. On the other hand, it is considered that the anionic surfactant inhibits the interaction between the fatty acid and the organic amine compound and the fatty acid can not be stably dissolved in the polishing composition, and good results can not be obtained.

Example 18 was obtained by adding 1% by mass of a polyalkylene glycol derivative as a defoaming agent, and similarly to Examples 1 to 17, excellent dissolution stability and a high polishing rate were obtained. Thus, when bubbles are generated during polishing, it has been found that addition of a defoaming agent to the polishing composition does not impair the effect of the present invention.

The polishing composition of the present invention is useful as a polishing agent for mirror-polishing a high-hardness and high-hardness material substrate such as a sapphire substrate for a light-emitting diode (LED), a SiC substrate for a power semiconductor device, a GaN substrate or an AlN substrate.

Claims (14)

(A) component: at least one abrasive selected from diamond, boron nitride, boron carbide and silicon carbide; (B) component: a fatty acid having a carbon number of 12 or more and 22 or less; (C) Wherein the abrasive composition (A) has an abrasive grain size of more than 1.0 占 퐉 and not more than 10.0 占 퐉 and a content of the component (C) is not more than 0.30 And the molar ratio [(D) / (B)] of the component (D) to the component (B) is 45/55 to 90/10. The method according to claim 1,
Wherein the content of the component (A) is 0.03 to 3.0 mass%, the content of the component (B) is 0.10 to 10 mass%, the content of the component (D) is 1.0 to 20 mass% By mass to 60% by mass to 98% by mass. 3. The method according to claim 1 or 2,
Wherein the molar ratio [(D) / (B)] of the component (D) to the component (B) is 50/50 to 70/30. 3. The method according to claim 1 or 2,
Wherein the abrasive grains are diamond. 3. The method according to claim 1 or 2,
Wherein the fatty acid is at least one selected from lauric acid and oleic acid. 3. The method according to claim 1 or 2,
Wherein the nonionic surfactant is at least one selected from polyetheramine and sorbitan ester-ethylene oxide adducts. 3. The method according to claim 1 or 2,
Wherein the nonionic surfactant is at least one selected from polyoxyethylene laurylamine, polyoxyethylene urea alkylamine, polyoxyethylene sorbitan monolaurate, and polyoxyethylene sorbitan monooleate. 3. The method according to claim 1 or 2,
Wherein the organic amine compound is an alkanolamine. 3. The method according to claim 1 or 2,
Wherein the organic amine compound is triethanolamine. 3. The method according to claim 1 or 2,
Wherein the dispersion medium contains at least one selected from ethylene glycol, diethylene glycol, and propylene glycol. 3. The method according to claim 1 or 2,
Wherein the dispersion medium is a mixture of a water-soluble organic solvent and water, and the mass ratio of the water-soluble organic solvent to water (water-soluble organic solvent / water) is 30/70 to 95/5. 3. The method according to claim 1 or 2,
Wherein the dispersion medium is a mixture of water and at least one selected from ethylene glycol, diethylene glycol, and propylene glycol. Wherein the substrate comprising at least one material selected from the group consisting of silicon carbide, sapphire, silicon carbide, gallium nitride, and aluminum nitride is polished by using the polishing composition according to claim 1 or 2. 14. The method of claim 13,
Wherein the substrate is a substrate for a light emitting diode including sapphire.