WO2021049154A1 - Polishing composition and polishing method using same - Google Patents

Abstract

The present invention provides a means capable of achieving a higher polishing rate than conventional means, for a polishing composition for polishing various materials, and particularly, for polishing various materials including a resin. The present invention relates to a polishing composition comprising alumina particles and a dispersion medium, wherein the alumina particles have a breaking strength of 0.5 GPa or more, or the alumina particles are prepared by a deflagration method.

Description

Polishing composition and polishing method using it

The present invention relates to a polishing composition and a polishing method using the same.

In recent years, new microfabrication technology has been developed along with the high integration and high performance of LSI. The chemical mechanical polishing (hereinafter, also abbreviated as “CMP”) method is one of them, and is a technique frequently used in the LSI manufacturing process, particularly in the multilayer wiring forming process.

This CMP method is also used for polishing the surface of a resin, and by applying the CMP method, a resin product with few surface defects can be obtained. From this, various studies have been made as polishing compositions for polishing various materials including resins.

Japanese Unexamined Patent Publication No. 2016-183212 discloses a polishing composition for polishing an object to be polished, which contains a resin having high rigidity and high strength. More specifically, Japanese Patent Application Laid-Open No. 2016-183212 has high rigidity and high strength due to a polishing composition containing an abrasive grain having a Mohs hardness and a surface acid amount of a predetermined value or more and a dispersion medium. It is disclosed that even a resin can be polished at a high polishing rate. Further, Japanese Patent Application Laid-Open No. 2016-183212 also discloses that the abrasive grains preferably contain α-alumina as a main component from the viewpoint of polishing speed.

Japanese Patent Application Laid-Open No. 2007-063442 (corresponding to US Patent Application Publication No. 2007/0044385) discloses a polishing composition of a synthetic resin object to be polished. More specifically, Japanese Patent Application Laid-Open No. 2007-063442 describes polishing of synthetic resins by using a polishing composition containing a polyurethane-based polymer surfactant having a specific structure and having a predetermined viscosity range. It is disclosed that the reduction of the composition for use and the reduction of the polishing ability can be suppressed. Further, Japanese Patent Application Laid-Open No. 2007-063442 also discloses that the polishing composition preferably contains α-alumina as abrasive grains from the viewpoint of polishing speed.

In recent years, even higher polishing speeds have been required for polishing various materials, especially for polishing various materials including resins. However, in the polishing composition of JP-A-2016-183212 and the polishing composition of JP-A-2007-063442, alumina containing α-alumina as a main component, which is a preferable abrasive grain, is used. However, there has been a problem that a sufficient polishing rate cannot always be obtained.

Therefore, an object of the present invention is to provide a means capable of achieving a higher polishing rate than the conventional one in a polishing composition used for polishing various materials, particularly various materials including a resin.

The present inventors have conducted diligent studies to solve the above problems. As a result, the present inventors have found that a remarkable effect of improving the polishing rate can be obtained by using alumina particles having a fracture strength of a predetermined value or more as the abrasive grains, and have completed the present invention.

The above problem of the present invention can be solved by the following means.

Contains alumina particles and a dispersion medium,
A polishing composition having a breaking strength of the alumina particles of 0.5 GPa or more.

Further, the above-mentioned problem of the present invention can be solved by the following means.

Contains alumina particles and a dispersion medium,
A polishing composition in which the alumina particles are alumina particles produced by an explosive combustion method.

Hereinafter, embodiments of the present invention will be described. The present invention is not limited to the following embodiments.

In this specification, "XY" indicating a range means "X or more and Y or less". Unless otherwise specified, the operation and physical properties are measured under the conditions of room temperature (range of 20 ° C. or higher and 25 ° C. or lower) / relative humidity of 40% RH or more and 50% RH or less.

Further, in the present specification, "(meth) acrylate" is a general term for acrylate and methacrylate. Similarly, compounds containing (meta) such as (meth) acrylic acid are a general term for compounds having "meta" in their names and compounds having no "meta".

<Polishing composition>
One embodiment of the present invention relates to a polishing composition containing alumina particles and a dispersion medium and having a breaking strength of the alumina particles of 0.5 GPa or more.

Further, another embodiment of the present invention relates to a polishing composition containing alumina particles and a dispersion medium, wherein the alumina particles are alumina particles produced by an explosive combustion method.

According to the present invention, in a polishing composition used for polishing various materials, particularly various materials including a resin, a means capable of achieving a higher polishing rate than before can be provided.

The present inventors speculate the mechanism by which the above-mentioned problems can be solved by the present invention as follows.

Conventionally, from the viewpoint of improving the mechanical polishing effect, it has been considered that the higher the hardness of the abrasive grains, the higher the polishing speed. However, the present inventors have found that abrasive grains having high hardness tend to be brittle and are easily broken by the stress applied during polishing, so that the stress cannot be sufficiently transmitted to the object to be polished. Therefore, simply selecting abrasive grains having high hardness does not provide a sufficient mechanical polishing effect, and a high polishing rate cannot be obtained.

On the other hand, the polishing composition according to one embodiment of the present invention has alumina particles having a breaking strength of a predetermined value or more. The fracture strength of the abrasive grains is an index of the amount of deformation of the abrasive grains that can be tolerated when stress is applied, but the fracture strength of the abrasive grains having a fracture strength of a predetermined value or more is unlikely to cause fracture due to deformation when stress is applied. Alternatively, the polishing composition according to another embodiment of the present invention has alumina particles produced by an explosive combustion method. Alumina particles produced by the explosive combustion method have a large amount of deformability and sphericity when stress is applied, and are unlikely to be destroyed by deformation when stress is applied. Also, in general, alumina particles have sufficient hardness. Therefore, when these alumina particles are used as the abrasive grains, the contact area between the abrasive grains and the object to be polished becomes larger due to the deformation of the abrasive grains when stress is applied, and the elastic force of the abrasive grains causes the object to be polished. A large stress will be transmitted.

The above mechanism is based on speculation, and its correctness does not affect the technical scope of the present invention. Similarly, the correctness of other inferences in the present specification does not affect the technical scope of the present invention.

[Abrasive grain]
The polishing composition according to the present invention contains alumina particles as abrasive grains. The alumina particles are alumina particles produced by an explosive combustion method described later, or are alumina particles having a breaking strength of 0.5 GPa or more.

Abrasive grains mechanically polish the object to be polished and improve the polishing speed. Since the alumina particles have sufficient hardness, the effect of improving the polishing rate, particularly the effect of improving the polishing rate of various materials including resin is high.

The breaking strength of the alumina particles is not particularly limited, but is preferably 0.5 GPa or more, more preferably 0.6 GPa or more, further preferably 0.65 GPa or more, and 0.7 GPa or more. It is even more preferably 0.75 GPa or more, and even more preferably 0.8 GPa or more. Within the above range, the polishing speed is further improved. The breaking strength of the alumina particles is preferably 2 GPa or less. Within the above range, the production suitability is further improved while maintaining a high polishing rate.

When the object to be polished contains silicon oxide, a preferable example of the breaking strength of the alumina particles is 0.8 GPa or more and 2 GPa or less. When the object to be polished contains an epoxy resin, a preferable example of the breaking strength of the alumina particles is 0.8 GPa or more and 2 GPa or less. When the object to be polished contains a polyimide resin, a preferable example of the breaking strength of the alumina particles is 0.7 GPa or more and 2 GPa or less, more preferably 0.75 GPa or more and 2 GPa or less, and further preferably 0.8 GPa or more. It is 2 GPa or less. When the object to be polished contains an acrylic resin, a preferable example of the breaking strength of the alumina particles is 0.7 GPa or more and 2 GPa or less, and more preferably 0.75 GPa or more and 2 GPa or less.

The breaking strength of alumina particles can be controlled by the manufacturing method and manufacturing conditions. In the manufacturing method, the alumina particles produced by the explosive combustion method described later have higher breaking strength. Further, in the explosive combustion method, the value of the fracture strength can be increased by pretreating the powder fluid of the metal alumina as the pre-raw material at a heating temperature of more than 1200 ° C. Further, from the viewpoint of ease of control, the heating temperature is preferably between 1250 and 1275 ° C.

The fracture strength of alumina particles is "Rapid test of tensile strength of rock by unshaped test piece, Yoshio Hiramatsu, Yukitoshi Oka, Hideo Kiyama, Journal of Japan Mining Association, Vol. 81, No. 932, 1024-1030, 1965". Can be calculated with reference to. Specifically, when particles (particularly spherical particles) are compressed, compressive stress is distributed near the loading point, but tensile stress is distributed almost all over the other parts. Therefore, the fracture strength of the alumina particles can be calculated according to the following formula by recording the obtained load-push displacement diagram and assuming that the point where the displacement increases rapidly is the point where the particles are fractured on a large scale.

Here, the breaking load P can be measured using a microcompression tester MCTW-500 manufactured by Shimadzu Corporation and a flat surface indenter made of diamond (φ = 50 μm). The method for measuring the average particle size d will be described later in the description of the average particle size. Details of the method for measuring and calculating the breaking strength of alumina particles will be described in Examples.

The breaking strength of the alumina particles calculated based on the above measurement can be obtained by taking out the alumina particles from the prepared polishing composition even if the powdered alumina particles which are the raw materials of the polishing composition are measured. Even if measured, the values are the same.

The alumina particles are preferably particles having a large sphericity, and more preferably spherical particles. In the present specification, the spherical particle represents a particle having a sphericity of 90% or more. With spherical particles, the polishing rate is further improved. It is presumed that spherical particles are less likely to be deformed when stress is applied or to be destroyed due to deformation, and can transmit a larger stress to the object to be polished.

More specifically, the sphericity of the alumina particles is preferably more than 50%, more preferably 60% or more, further preferably 65% or more, still more preferably 70% or more. It is preferably 80% or more, and extremely preferably 90% or more. Within the above range, the polishing speed is further improved. The sphericity of the alumina particles is preferably 99.9% or less. Within the above range, the production suitability is further improved.

When the object to be polished contains silicon oxide, a preferable example of the sphericity of the alumina particles is 98% or more and less than 99.5%. When the object to be polished contains an epoxy resin, a preferable example of the sphericity of the alumina particles is 98% or more and less than 99.5%. When the object to be polished contains a polyimide resin, a preferable example of the sphericity of the alumina particles is 90% or more and 99.9% or less, more preferably 95% or more and 99.9% or less, and further preferably. , 98% or more and less than 99.5%. When the object to be polished contains an acrylic resin, a preferable example of the sphericity of the alumina particles is 99.5% or more and 99.9% or less, and more preferably 99.5% or more and 99.9% or less. ..

The sphericity of alumina particles can be controlled by the manufacturing method and manufacturing conditions. For example, the alumina particles produced by the explosive combustion method described later have a higher sphericity, and the sphericity generally exceeds 50%. Further, in the detonation method, the value of sphericity can be increased by lowering the heating temperature after the detonation reaction to 1225 ° C. or lower. In the heat treatment, a known device / method such as a rotary kiln can be adopted.

For the sphericity of alumina particles, 100 particles are randomly selected from the images measured by a scanning electron microscope (SEM) (manufactured by Hitachi High-Tech Co., Ltd., product name: SU8000), and the average major axis and average minor axis of these particles are measured. After calculating, it can be calculated according to the following formula. Details of the method for measuring and calculating the sphericity of the alumina particles will be described in Examples.

The sphericity calculated based on the above measurement can be measured by taking out the alumina particles from the prepared polishing composition even if the sphericity is measured in the state of powdered alumina particles which are the raw materials of the polishing composition. Even so, the values are equivalent.

The alumina particles are not particularly limited as long as they are alumina particles produced by the explosive combustion method or the alumina particles have a breaking strength of 0.5 GPa or more. For example, alumina particles containing at least one selected from α-alumina, γ-alumina, δ-alumina, θ-alumina, η-alumina and κ-alumina can be mentioned. Among these, alumina particles containing a γ phase (alumina particles containing γ-alumina) are preferable as the crystal phase, and alumina particles containing a γ phase as the main crystal phase (alumina containing γ-alumina as a main component). It is more preferable that it is a particle).

In the present specification, when the peak of the γ phase appearing at the position of 2θ = 46 ° is confirmed from the powder X-ray diffraction spectrum obtained by using the powder X-ray diffractometer, the alumina particles “set the γ phase as the crystal phase”. Including ". Further, in the present specification, when the γ conversion rate described later is more than 50%, it is determined that the alumina particles "include the γ phase as the main crystal phase" (upper limit 100%). By using alumina particles containing a γ phase as the crystal phase, the polishing rate is further improved, and when the crystal phase is mainly the γ phase, the effect is further enhanced. It is presumed that the γ phase has a large deformable amount when stress is applied and contributes to the improvement of fracture strength. The alumina particles produced by the explosive combustion method described later tend to have a particularly high γ-phase content when the peak of the γ-phase appearing at the position of 2θ = 46 ° is confirmed.

Further, the pregelatinization rate of the alumina particles is preferably less than 50%, more preferably less than 45%, and further preferably less than 40% (lower limit 0%). Within the above range, the polishing speed is further improved. Although the α phase has high hardness, it tends to be brittle, and it is presumed that keeping the content below a certain level contributes to the improvement of fracture strength when stress is applied. Here, the pregelatinization rate [%] is the peak height (I25) of the α phase (012) plane appearing at the position of 2θ = 25.6 ° from the powder X-ray diffraction spectrum obtained by using the powder X-ray diffractometer. It can be calculated by the following formula from .6) and the peak height (I46) of the γ phase appearing at the position of 2θ = 46 °.

When the main crystal phase contains a γ phase, it is preferable to further include an α phase as a crystal phase. In this case, the hardness is further improved and the polishing speed is further improved. At this time, the pregelatinization rate is preferably more than 0% and less than 40%.

Further, in the present specification, the gamma conversion rate [%] is the peak of the α phase (012) plane appearing at the position of 2θ = 25.6 ° in the powder X-ray diffraction spectrum obtained by using the powder X-ray diffractometer. It is defined as a value calculated from the following formula from the height (I25.6) and the peak height (I46) of the γ phase appearing at the position of 2θ = 46 °.

The type of crystal phase in the alumina particles and the content ratio thereof can be controlled by the production method and production conditions. For example, the alumina particles produced by the explosive combustion method described later have a higher gamma conversion rate and a lower pregelatinization rate. Further, in the detonation method, the pregelatinization rate can be lowered by lowering the heating temperature after the detonation reaction to 1225 ° C.

The type of crystal phase in the alumina particles, the measurement of the pregelatinization rate and the gamma conversion rate, the measurement of the calculation method, and the details of the calculation method will be described in Examples.

Further, the pregelatinization rate and the gamma conversion rate calculated based on the above measurement can be obtained from the prepared polishing composition even if the powdery alumina particles which are the raw materials of the polishing composition are measured. Even if the values are taken out and measured, the values are the same.

The average particle size of the alumina particles is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.1 μm or more, further preferably 5 μm or more, and more preferably 8 μm or more. It is more preferably 10 μm or more, and particularly preferably 10 μm or more. Within the above range, the polishing speed is further improved. The average particle size of the alumina particles is preferably 500 μm or less, more preferably 100 μm or less, further preferably 50 μm or less, further preferably 20 μm or less, and further preferably 15 μm or less. Is particularly preferred. Within the above range, defects such as scratches on the object to be polished are further reduced.

When the object to be polished contains silicon oxide, a preferable example of the average particle size of the alumina particles is 5 μm or more and 20 μm or less, and more preferably 12 μm or more and 20 μm or less. When the object to be polished contains an epoxy resin, a preferable example of the average particle size of the alumina particles is 5 μm or more and 20 μm or less, and more preferably 12 μm or more and 20 μm or less. When the object to be polished contains a polyimide resin, a preferable example of the average particle size of the alumina particles is 10 μm or more and 20 μm or less, and more preferably 12 μm or more and 20 μm or less. When the object to be polished contains an acrylic resin, a preferable example of the average particle size of the alumina particles is 8 μm or more and 20 μm or less, and more preferably 8 μm or more and 10 μm or less.

In the present specification, the average particle size of alumina particles can be measured using a particle size distribution measuring device (Microtrack MT3000II manufactured by Microtrack Bell Co., Ltd.). The details of the method for measuring the average particle size of the alumina particles will be described in Examples.

Further, the average particle size obtained based on the above measurement can be measured by using the polishing composition containing the alumina particles even if it is measured by using the powdered alumina particles which are the raw materials of the polishing composition. However, the values are the same.

The content of the alumina particles is not particularly limited, but is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and more preferably 0.5, based on the total mass of the polishing composition. It is more preferably mass% or more, and particularly preferably 2 mass% or more. The higher the content of alumina particles, the higher the polishing rate. The content of the alumina particles is preferably 25% by mass or less, more preferably 15% by mass or less, still more preferably 10% by mass or less, based on the total mass of the polishing composition. , 8% by mass or less, and particularly preferably 6% by mass or less. Within the above range, the occurrence of defects such as scratches on the object to be polished is further reduced.

The method for producing the alumina particles is not particularly limited, and a known method can be appropriately used. The method for producing the alumina particles is preferably a method for obtaining alumina particles having a higher breaking strength, for example, alumina particles having a breaking strength of 0.5 GPa or more. Of these, the explosion method (VMC method: Vaporized Metal Combustion Method) is preferable. That is, the alumina particles are preferably alumina particles produced by the explosive combustion method. The explosive combustion method can obtain alumina particles having high fracture strength and sphericity, and the polishing speed is further improved by using the particles.

The explosive combustion method is "a chemical flame is formed in an atmosphere containing oxygen, and a metal powder that forms a part of the target oxide ultrafine particles is added into the chemical flame in an amount sufficient to form a dust cloud. , A method of synthesizing ultrafine oxide particles by causing explosion. " Details of the explosion method are described in known documents such as JP-A-60-255602 (corresponding to US Pat. No. 4,705,762), and alumina particles are produced with reference to these descriptions. can do.

[Dispersion medium]
The polishing composition according to the present invention contains a dispersion medium. The dispersion medium disperses or dissolves each component.

The dispersion medium preferably contains water. Further, from the viewpoint of preventing the influence of impurities on other components of the polishing composition, it is preferable to use water having the highest possible purity. Specifically, pure water, ultrapure water, or distilled water from which impurity ions have been removed with an ion exchange resin and then foreign substances have been removed through a filter is preferable. Further, as the dispersion medium, an organic solvent or the like may be further contained for the purpose of controlling the dispersibility of other components of the polishing composition.

[PH regulator]
The polishing composition according to one embodiment of the present invention preferably further contains a pH adjuster. The pH adjuster can contribute to the pH adjustment of the polishing composition by selecting the type and the amount of the addition.

The pH adjusting agent is not particularly limited as long as it is a compound having a pH adjusting function, and known compounds can be used. Examples of the pH adjuster include acids and alkalis.

As the acid, either an inorganic acid or an organic acid may be used. The inorganic acid is not particularly limited, and examples thereof include sulfuric acid, nitric acid, boric acid, carbonic acid, hypophosphorous acid, phosphoric acid, and phosphoric acid. The organic acid is not particularly limited, and is, for example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, 2-methylbutyric acid, n-hexanoic acid, 3,3-dimethylbutyric acid, 2-ethylbutyric acid, 4-methylpentane. Acids, n-heptanoic acid, 2-methylhexanoic acid, n-octanoic acid, 2-ethylhexanoic acid, benzoic acid, glycolic acid, salicylic acid, glyceric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, Examples thereof include carboxylic acids such as pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid and lactic acid, and sulfonic acids such as methanesulfonic acid, ethanesulfonic acid and isethionic acid. Among these, inorganic acids are preferable, and nitric acid is more preferable.

The alkali is not particularly limited, and examples thereof include hydroxides of alkali metals such as potassium hydroxide, quaternary ammonium salts such as ammonia, tetramethylammonium and tetraethylammonium, and amines such as ethylenediamine and piperazine. Of these, ammonia is preferable.

The pH adjuster can be used alone or in combination of two or more.

The content of the pH adjuster is not particularly limited, and it is preferable that the pH value is an amount within a preferable range described later.

[Processing accelerator]
The polishing composition according to one embodiment of the present invention preferably further contains a processing accelerator. As the processing accelerator, a graft polymer having an anionic functional group in the stem polymer portion (hereinafter, simply referred to as “graft polymer A”) is preferable. When the graft polymer A is used in combination with the above-mentioned alumina particles which are abrasive grains, it acts to improve the polishing rate, particularly when the material to be polished is a resin. It is presumed that the reason for this is that the graft polymer A adjusts the zeta potential and wettability of the object to be polished, and facilitates the contact between the alumina abrasive grains and the object to be polished.

The anionic functional group contained in the graft polymer A is not particularly limited, and is, for example, a carboxy group or a salt group thereof, a sulfo group or a salt group thereof, a phosphonic acid group or a salt group thereof, a phosphoric acid group or a salt thereof. The group of. Among these, a carboxy group or a salt group thereof is preferable from the viewpoint of further enhancing the polishing rate, particularly the effect of improving the polishing rate when the material to be polished is a resin. For this reason, the stem polymer portion is preferably a (co) polymer containing a structural unit derived from a monomer having a carboxy group or a salt group thereof. And it is more preferable that it is a (co) polymer containing at least a structural unit derived from (meth) acrylic acid or a salt thereof. In addition, in this specification, a (co) polymer means a generic term including a copolymer and a homopolymer.

Further, the (co) polymer containing at least a structural unit derived from (meth) acrylic acid or a salt thereof may further contain a structural unit derived from another monomer. The other monomer is not particularly limited, and a monomer having a carbon-carbon double bond such as a known monomer having a vinyl group or a known monomer having a (meth) acryloyl group can be used. A preferred example is given. Specific examples of other monomers are not particularly limited, but are, for example, alkyl esters of (meth) acrylic acids such as methyl (meth) acrylate and ethyl (meth) acrylate; Amino alkyl ester of (meth) acrylic acid; monoester of (meth) acrylic acid such as hydroxyethyl methacrylate; vinyl alkyl ether such as vinyl methyl ether and vinyl ethyl ether; vinyl sulfonic acid or a salt thereof; styrene sulfonic acid Or a salt thereof; allyl sulfonic acid or a salt thereof; metharyl sulfonic acid or a salt thereof; (meth) acrylamide alkyl sulfonic acid or a salt thereof; vinyl acetate; vinyl esterate; N-vinylimidazole; N-vinylacetamide; N-vinyl Formamide; N-vinylcaprolactam; N-vinylcarbazole; (meth) acrylamide; N-alkyl (meth) acrylamide; N-methylol (meth) acrylamide; N, N-methylenebis (meth) acrylamide; glycol di (meth) acrylate; Divinylbenzene; glycol diallyl ether; unsaturated alcohol such as allyl alcohol; maleic anhydride or a salt thereof; maleic acid ester and the like.

The form of the above poly (meth) acrylate salt and the form when the other monomer is a salt are not particularly limited, but are preferably an alkali metal salt or an ammonium salt.

The number of anionic functional groups contained in the graft polymer A is not particularly limited as long as it is 1 or more per stem polymer portion, but it is preferably 2 or more.

The branch portion (graft chain) constituting the graft polymer A is preferably a polymer containing a polyoxyalkylene chain such as a polyoxyethylene chain, a polyoxypropylene chain, and a polyoxybutylene chain in the molecule. When the branch portion is such a polymer, the effect of improving the polishing speed, particularly the polishing speed when the material to be polished is a resin, is further enhanced. The polymer containing a polyoxyalkylene chain in the molecule that can form a branch portion is not particularly limited, but for example, it has a hydroxy group at the terminal and undergoes an esterification reaction with the carboxy group of the stem polymer portion, or the stem. Examples thereof include a polymer capable of forming a graft bond by an addition reaction with a hydroxy group in the polymer portion. Specific examples thereof are not particularly limited, but are, for example, oxyalkylenes such as polyethylene glycol, polypropylene glycol, polybutylene glycol, polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyoxyethylene alkenyl ether, and polyoxypropylene alkenyl ether. Examples include (co) polymers having a group. Further, as a polymer containing a polyoxyalkylene chain in the molecule that can form a branch portion, for example, a polymer having an amino group at the terminal and forming a graft bond by an amidation reaction with a carboxy group of the stem polymer portion is formed. Examples include the polymer to be obtained. Specific examples thereof are not particularly limited, and examples thereof include polyoxyethylene alkylamines and polyoxypropylene alkylamines. From these facts, an example of a preferable graft polymer A is a graft polymer having an anionic functional group in the stem polymer portion and a polyoxyalkylene chain in the branch portion.

The number of branch portions of the graft polymer A is not particularly limited as long as it is one or more for one trunk polymer portion, but it is preferably two or more.

An example of the graft polymer A is a polymer containing a repeating unit represented by the following general formula (1).

In the above general formula (1)
R ¹ independently represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.
R ² independently represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms.
R ³ , R ⁴ , and R ⁵ are each independently selected from -C ₂ H _{4 O-, -C 3} H ₆ O-, and -C ₄ H ₈ O-, respectively. Represents a unit
R ⁶ independently represents a hydrogen atom or a carboxy group, respectively.
A is an independently single bond, -O-, -COO-, an oxyalkylene group having 1 to 9 carbon atoms (-C _q H _2q O- (q is an arbitrary integer of 1 to 9)), Represents an amide group (-CONH-), or -NH-
l, m, and n independently represent arbitrary integers from 0 to 100, and l + m + n> 0.
* Represents a bond.

Further, as an example of the graft polymer A, in addition to the repeating unit represented by the above general formula (1), a polymer further containing at least one of the repeating units represented by the following general formulas (2) to (4) may be used. Can be mentioned.

In the above general formula (2)
R ⁷ independently represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.
R ⁸ independently represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms.
A'independently represents a single bond, -O-, or -NH-, respectively.
In the above general formulas (2) to (4),
* Represents a bond.

In the above general formulas (1) to (4), it is preferable that the bond * is bonded to another repeating unit or a hydrogen atom.

When the graft polymer A is a polymer containing both the repeating unit represented by the general formula (1) and the repeating unit represented by at least one of the general formulas (2) to (4), the moles thereof. The ratio is preferably the repeating unit represented by the general formula (1): the sum of the repeating units represented by the general formulas (2) to (4) = 1: 20 to 20: 1, preferably 1:10 to 20: 1. It is more preferably 10: 1, more preferably 1: 3 to 3: 1, and particularly preferably 1: 1.

The weight average molecular weight of the graft polymer A is not particularly limited, but is preferably 500 or more, more preferably 1,000 or more, further preferably 5,000 or more, and particularly preferably 7,000 or more. Within the above range, the adhesion rate of the graft polymer A to the base material becomes higher, so that the expected surface characteristics of the base material can be obtained better. The weight average molecular weight of the graft polymer A is preferably 2,000,000 or less, more preferably 100,000 or less, and even more preferably 30,000 or less. Within the above range, the graft polymer A can be more appropriately removed from the surface of the base material during polishing, so that the expected polishing rate can be obtained more stably. The weight average molecular weight can be determined by gel permeation chromatography (GPC) in terms of polyethylene glycol using a GPC device (model: Prominence + ELSD detector (ELSD-LTII) manufactured by Shimadzu Corporation) or the like. The details of the method for measuring the weight average molecular weight will be described in Examples.

As the processing accelerator, a synthetic product or a commercially available product may be used. Examples of commercially available products include, but are not limited to, Marialim (registered trademark) AKM0531, SC0505K, SC0708A, SC1015F manufactured by NOF CORPORATION.

The processing accelerator can be used alone or in combination of two or more.

The content of the processing accelerator is not particularly limited, but is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, based on the total mass of the polishing composition. It is more preferably 01% by mass or more, further preferably 0.1% by mass or more, and particularly preferably 0.5% by mass or more. Within the above range, the polishing speed, particularly when the material to be polished is a resin, is further improved. The content of the processing accelerator is preferably 25% by mass or less, more preferably 15% by mass or less, and further preferably 10% by mass or less, based on the total mass of the polishing composition. preferable. Within the above range, the contact frequency between the abrasive grains and the base material can be further increased.

The ratio of the content of the processing accelerator to the content of the abrasive grains (content of the processing accelerator (mass%) / content of the abrasive grains (mass%)) is not particularly limited, but must be 0.01 or more. Is more preferable, 0.05 or more is more preferable, and 0.15 or more is further preferable. The ratio of the content of the processing accelerator to the content of the abrasive grains (content of the processing accelerator (mass%) / content of the abrasive grains (mass%)) is preferably 10 or less, and is 5 or less. Is more preferable, and 1.5 or less is further preferable. Within these ranges, the frequency of contact between the abrasive grains and the substrate can be further increased.

[Other ingredients]
The polishing composition according to one embodiment of the present invention may further contain other components other than those described above as long as the effects of the present invention are not impaired. The other components are not particularly limited, and components used in known polishing compositions can be used. Examples thereof include wetting agents, surfactants, chelating agents, preservatives, fungicides, dissolved gases, oxidizing agents, reducing agents and the like.

[PH]
The pH of the polishing composition according to one embodiment of the present invention is not particularly limited, but is preferably 1 or more, and more preferably 2 or more. Within the above range, a higher polishing rate can be obtained while considering safety. The pH of the polishing composition is preferably 12 or less, more preferably 10 or less. When a resin such as glass epoxy, polyimide, or acrylic is to be polished, it is more preferably 9 or less, further preferably 7 or less, particularly preferably 6 or less, and preferably 4 or less. Most preferred. Within the above range, higher safety and higher polishing rate can be obtained. From this, a preferable example of the pH range is 1 or more and 12 or less, and more preferably 2 or more and 10 or less.

When the object to be polished contains a polyimide resin, a preferable example of the pH range is 2 or more and less than 7, more preferably 2 or more and 5 or less, and further preferably 2 or more and 4 or less. When the object to be polished contains an acrylic resin, a preferable example of the pH range is 2 or more and less than 7, more preferably 2 or more and 5 or less, and further preferably 2 or more and 4 or less.

The pH value can be confirmed with a pH meter (HORIBA, Ltd. model number: LAQUA (registered trademark)).

[Manufacturing method of polishing composition]
The method for producing the polishing composition (preparation method) is not particularly limited, and for example, a production method including stirring and mixing alumina particles having a breaking strength of 0.5 GPa or more and a dispersion medium can be appropriately adopted. .. Further, for example, a production method including producing alumina particles by an explosive combustion method and stirring and mixing the alumina particles and a dispersion medium can be appropriately adopted. In these methods, the pH adjuster and other components may be further stirred and mixed. Details of each component added are as described above. From this, as a preferable example of the method for producing the polishing composition, the production of alumina particles having a breaking strength of 0.5 GPa or more by the explosive combustion method, and the stirring and mixing of the alumina particles and the dispersion medium are performed. Examples include manufacturing methods including. The details of the explosion method are the same as those described above for the polishing composition.

The temperature at which each component is mixed is not particularly limited, but is preferably 10 to 40 ° C., and may be heated to increase the dissolution rate. Further, the mixing time is not particularly limited.

The polishing composition may be adjusted by diluting the stock solution of the polishing composition with a diluting solution such as water, for example, 10 times or more.

[Object to be polished]
The object to be polished by the polishing composition according to the present invention is not particularly limited, and an object to be polished in a known CMP step can be appropriately selected.

The Si element-containing material is not particularly limited, and is, for example, polysilicon, amorphous silicon, single crystal silicon, n-type doped single crystal silicon, p-type doped single crystal silicon, Si-based alloys such as SiGe, silicon oxide (SiO _2). ), BD (Black Diamond: SiOCH), FSG (Fluorosilicate Glass), HSQ (Hydrogen silsesquioxane), CYCLOTENE, SiLK, MSQ (Methylsilsesquioxane), Silicon Nitride (SiN), Silicon Carbonide (SiCN), etc. Be done. Here, the silicon oxide is preferably silicon oxide derived from tetraethyl orthosilicate (TEOS).

The resin is not particularly limited, and is, for example, an acrylic resin such as methyl poly (meth) acrylate, methyl methacrylate-methyl acrylate copolymer, urethane (meth) acrylate resin; epoxy resin; ultra-high molecular weight polyethylene (UHPE). ) Etc. olefin resin; phenol resin; polyamide resin (PA); polyimide resin (PI); polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyester resin such as unsaturated polyester resin; polycarbonate resin (PC); Polystyrene resin such as otakutic polystyrene (SPS); polynorbornene resin; polybenzoxazole (PBO); polyacetal (POM); modified polyphenylene ether (m-PPE); amorphous polyarylate (PAR); polysulfone (PSF); poly Examples thereof include ether sulfone (PES); polyphenylene sulfide (PPS); polyether ether ketone (PEEK); polyetherimide (PEI); fluororesin; liquid crystal polymer (LCP).

In addition, the resin shall also include reinforced plastic in which fibers such as glass fiber and carbon fiber are compounded to improve the strength.

Among these, the polishing target is preferably a polishing target containing a Si element-containing material or a resin on the polishing surface, and more preferably a polishing target containing silicon oxide or a resin on the polishing surface. Further, it is more preferable that the object to be polished contains a resin on the polished surface, and it is even more preferable that the object to be polished contains an epoxy resin, a polyimide resin or an acrylic resin on the polished surface. Then, it is particularly preferable that the object to be polished contains a polyimide resin or an acrylic resin on the polished surface. When used for polishing an object to be polished containing resin on the polished surface, especially when used for polishing an object to be polished containing polyimide resin or acrylic resin on the polished surface, the polishing speed is significantly improved. ..

In addition, in the object to be polished containing resin on the polished surface, the resin is calcium carbonate, magnesium carbonate, barium sulfate, magnesium sulfate, aluminum silicate, titanium oxide, alumina, zinc oxide, silicon dioxide, kaolin, talc, glass beads, seri. Inorganic fillers such as site-active clay, bentonite, and aluminum nitride, and organic fillers such as polyester fine particles, polyurethane fine particles, and rubber fine particles may be further contained.

These Si element-containing materials or resins can be used alone or in combination of two or more.

Further, the object to be polished may contain a material different from the Si element-containing material or resin as the polishing surface. Examples of such materials include copper (Cu), aluminum (Al), tantalum (Ta), tantalum nitride (TaN), titanium (Ti), titanium nitride (TiN), nickel (Ni), ruthenium (Ru), and the like. Examples thereof include cobalt (Co), tungsten (W), and tungsten nitride (WN).

<Polishing method>
Another aspect of the present invention relates to a polishing method for polishing an object to be polished using the above-mentioned polishing composition. Preferred examples of the object to be polished according to this embodiment are the same as those mentioned in the above description of the polishing composition. For example, it is preferable to polish an object to be polished containing a resin on the polished surface.

When polishing the object to be polished using the polishing composition, it can be performed using the equipment and conditions used for normal polishing. Examples of a general polishing device include a single-sided polishing device and a double-sided polishing device. In a single-sided polishing device, generally, a holder called a carrier is used to hold the object to be polished, and while supplying the polishing composition from above, a surface plate having a polishing pad attached to one side of the object to be polished is formed. One side of the object to be polished is polished by pressing and rotating the surface plate. In a double-sided polishing device, generally, a holder called a carrier is used to hold an object to be polished, and while supplying a polishing composition from above, a surface plate having a polishing pad attached to the facing surface of the object to be polished. And rotate them in the relative direction to polish both sides of the object to be polished. At this time, polishing is performed by the physical action of friction between the polishing pad and the polishing composition and the object to be polished, and the chemical action that the polishing composition brings to the object to be polished. As the polishing pad, a porous material such as non-woven fabric, polyurethane, or suede can be used without particular limitation. It is preferable that the polishing pad is processed so that the polishing liquid collects.

Polishing conditions include, for example, polishing load, surface plate rotation speed, carrier rotation speed, flow rate of polishing composition, polishing time, and the like. These polishing conditions are not particularly limited, but for example, the polishing load is preferably 0.1 psi or more and 10 psi or less, and more preferably 0.5 psi or more and 8.0 psi or less per unit area of the object to be polished. More preferably, it is 1.0 psi or more and 6.0 psi or less. Generally, the higher the load, the higher the frictional force due to the abrasive grains, and the higher the mechanical processing force, so that the polishing speed increases. Within this range, a sufficient polishing rate can be exhibited, and damage to the object to be polished due to a load and defects such as scratches on the surface can be suppressed. The surface plate rotation speed and the carrier rotation speed are preferably 10 to 500 rpm. The supply amount of the polishing composition may be any supply amount (flow rate) that covers the entire polishing object, and may be adjusted according to conditions such as the size of the polishing object. The method of supplying the polishing composition to the polishing pad is also not particularly limited, and for example, a method of continuously supplying the polishing composition with a pump or the like is adopted. Further, the processing time is not particularly limited as long as the desired processing result can be obtained, but it is preferably a shorter time due to the high polishing rate.

Further, another aspect of the present invention relates to a method for producing a polished object, which comprises a step of polishing the object to be polished by the above-mentioned polishing method. Preferred examples of the object to be polished according to this embodiment are the same as those mentioned in the above description of the polishing composition. As a preferable example, there is a method for manufacturing an electronic circuit board, which comprises polishing an object to be polished containing a resin by the above-mentioned polishing method.

Although embodiments of the present invention have been described in detail, this is descriptive and exemplary and not limiting, and it is clear that the scope of the invention should be construed by the appended claims. Is.

The present invention includes the following aspects and forms:
1. 1. Contains alumina particles and a dispersion medium,
A polishing composition having a breaking strength of the alumina particles of 0.5 GPa or more;
2. The above 1. Alumina particles are alumina particles produced by the explosive combustion method. The polishing composition according to.
3. 3. Contains alumina particles and a dispersion medium,
A polishing composition in which the alumina particles are alumina particles produced by an explosive combustion method;
4. 1. The sphericity of the alumina particles exceeds 50%. ~ 3. The polishing composition according to any one of the above;
5. The alumina particles contain a γ phase as a crystal phase, as described above. 1. 1. ~ 4. The polishing composition according to any one of the above;
6. The pregelatinization rate of the alumina particles is less than 50%. ~ 5. The polishing composition according to any one of the above;
7. The pH is 1 or more and 12 or less. ~ 6. The polishing composition according to any one of the above;
8. The above 1. The breaking strength of the alumina particles is 0.6 GPa or more. ~ 7. The polishing composition according to any one of the above;
9. The above 1. The breaking strength of the alumina particles is 2 GPa or less. ~ 8. The polishing composition according to any one of the above;
10. The sphericity of the alumina particles is 99.9% or less. ~ 9. The polishing composition according to any one of the above;
11. 1. A graft polymer having an anionic functional group is further contained in the stem polymer portion. ~ 10. The polishing composition according to any one of the above;
12. 1. Used for polishing an object to be polished containing resin on the polished surface. ~ 11. The polishing composition according to any one of the above;
13. Producing alumina particles by the explosion method and
The alumina particles and the dispersion medium are mixed by stirring.
Above 1. ~ 12. The method for producing a polishing composition according to any one of the above;
14. Above 1. ~ 12. Using the polishing composition according to any of the above, or
13. A polishing composition is produced by the production method described in the above, and the polishing composition is used to prepare the polishing composition.
Polishing method for polishing the object to be polished;
15. The object to be polished is an object to be polished containing a resin on the polished surface. The polishing method described in.

The present invention will be described in more detail with reference to the following examples and comparative examples. However, the technical scope of the present invention is not limited to the following examples. Unless otherwise specified, "%" and "parts" mean "mass%" and "parts by mass", respectively.

<Abrasive grains>
[Manufacturing of abrasive grains A1 to A5]
The abrasive grains A1 to A5 shown in Table 1 below were prepared by the explosive combustion method with reference to the examples of JP-A-60-255602.

[Synthesis of abrasive grains A6 to A9]
As described in paragraph "0013" of JP-A-2006-36864, the condition that the calcination temperature of aluminum hydroxide is in the range of 1100 to 1500 ° C. and the calcination time is in the range of 1 to 5 hours. After calcination, it was pulverized using an aluminum oxide pole having a diameter of 20000 μm. Abrasive grains A6 to A9 were produced by such a method for producing alumina particles (crushing method) by baking and then pulverizing as necessary. In the production of these abrasive grains, the crushing time was controlled so that the values of the average particle diameters shown in Table 1 below could be obtained.

[Manufacturing of abrasive grains A10 and A11]
Abrasive grains A10 and A11 shown in Table 1 below prepared by a method for producing alumina particles (hydrolysis method) by hydrolyzing aluminum alkoxide were prepared.

[Analysis of crystal phase type and content]
(Type of crystal phase contained in alumina particles)
For powdery abrasive grains (alumina particles), a powder X-ray diffraction spectrum was obtained using a powder X-ray diffractometer (Fully automatic multipurpose X-ray diffractometer SmartLab manufactured by Rigaku Co., Ltd.), and the peak of the powder X-ray diffraction spectrum was obtained. The type of crystal phase contained in the alumina particles was determined from the position. Here, when the peak of the α phase (012) plane appearing at the position of 2θ = 25.6 ° is confirmed in the powder X-ray diffraction spectrum, it is determined that the alumina particles “include the α phase as the crystal phase”. .. When the peak of the γ phase appearing at the position of 2θ = 46 ° was confirmed, it was determined that the alumina particles “contain the γ phase as the crystal phase”.

(Pregelatinization rate)
The pregelatinization rate [%] is the peak height (I25.6) of the α phase (012) plane appearing at the position of 2θ = 25.6 ° in the powder X-ray diffraction spectrum obtained by using the powder X-ray diffractometer. And the peak height (I46) of the γ phase appearing at the position of 2θ = 46 °, it was calculated by the following formula.

(Main crystal phase)
When the pregelatinization rate was more than 50%, it was determined that the alumina particles "contain the α phase as the main crystal phase". Further, in the powder X-ray diffraction spectrum obtained by using the powder X-ray diffractometer, the peak height (I25.6) of the α phase (012) plane appearing at the position of 2θ = 25.6 ° and 2θ = 46 °. From the peak height (I46) of the γ phase appearing at the position of, the value calculated from the following formula is defined as the γ conversion rate [%]. When the gamma conversion rate was more than 50%, it was determined that the alumina particles "contain the gamma phase as the main crystal phase".

[Spherical degree]
For powdered abrasive grains (alumina particles), 100 abrasive grains were randomly selected from images measured with a scanning electron microscope (SEM) (product name: SU8000 manufactured by Hitachi High-Tech Co., Ltd.), and their average major axis and average. The minor axis was measured and calculated. Subsequently, the sphericity of the abrasive grains was calculated according to the following formula using the values of the average major axis and the average minor axis.

[Average particle size]
The powdery abrasive grains (alumina particles) were measured using a particle size distribution measuring device (Microtrack MT3000II manufactured by Microtrack Bell Co., Ltd.), and the average particle size was evaluated.

〔destruction strength〕
For powdery abrasive grains (alumina particles), a load-push displacement diagram was obtained by the following measuring device and measuring conditions. Then, the fracture strength of the abrasive grains was calculated according to the following formula, assuming that the point where the displacement suddenly increased was the point where large-scale fracture occurred in the particles.

(Measuring equipment and measurement conditions)
Measuring device: Shimadzu Corporation micro compression tester MCTW-500,
Indenter used: Diamond flat indenter (φ = 50 μm),
Load speed: 7.747 mN / s: Constant load speed method,
Measurement atmosphere: Room temperature in the atmosphere.

Table 1 below shows the characteristics (material and manufacturing method) of each abrasive grain and the evaluation results of pregelatinization rate, main crystal phase, average particle size, sphericity, average major axis and average minor axis, and fracture strength. ..

In Table 1 below, when the pregelatinization rate is <40 [%], it means that although the α phase is included as the crystal phase, the value of the pregelatinization rate is more than 0% and less than 40%.

<Polishing composition>
[Preparation of Polishing Compositions P1 to P10 and P13 to P19]
Abrasive grains of the types shown in Table 3 below, nitric acid as a pH adjuster, and water as a dispersion medium were added and mixed by stirring to obtain polishing compositions P1 to P10 and P13 to P19 (mixing temperature). Approximately 25 ° C., mixing time: approximately 10 minutes). At this time, the amount of abrasive grains added is set to the concentration [mass%] shown in Table 3 below with respect to the total mass of the prepared polishing composition, and the amount of pH adjuster added is set to the amount of the prepared polishing composition. The pH value of the composition was set to the value shown in Table 3 below.

[Preparation of Polishing Compositions P11 and P12]
Abrasive grains of the types shown in Table 3 below, ammonia as a pH adjuster, and water as a dispersion medium were added and mixed by stirring to obtain polishing compositions P11 and P12 (mixing temperature: about 25 ° C., Mixing time: about 10 minutes). At this time, the amount of abrasive grains added is set to the concentration [mass%] shown in Table 3 below with respect to the total mass of the prepared polishing composition, and the amount of pH adjuster added is set to the amount of the prepared polishing composition. The pH value of the composition was set to the value shown in Table 3 below.

[Preparation of Polishing Compositions P20-35]
Abrasive grains of the types shown in Table 4 below, processing accelerators of the types shown in Table 4 below, or comparative compounds for confirming the effects of the processing accelerators (hereinafter, also simply referred to as "comparative compounds"), and pH adjustment. Nitric acid as an agent and water as a dispersion medium were added and mixed by stirring to obtain polishing compositions P20 to 35 (mixing temperature: about 25 ° C., mixing time: about 10 minutes). At this time, the amount of abrasive grains added and the amount of processing accelerator or comparative compound added are set to the concentration [mass%] shown in Table 4 below with respect to the total mass of the prepared polishing composition, and the pH is set. The amount of the adjusting agent added was set so that the pH value of the prepared polishing composition was the value shown in Table 4 below.

The processing accelerators and comparative compounds used in the preparation of the polishing compositions P20-35 are shown below:
-Compound A: Marialim (registered trademark) SC0505K (manufactured by NOF CORPORATION; graft polymer; polyoxyalkylene chain having an anionic functional group in the stem polymer part and containing a polyoxyalkylene chain in the branch part (graft chain). Short length; Mw = 8,000 or more and 10,000 or less), processing accelerator,
-Compound B: Marialim (registered trademark) AKM0531 (manufactured by NOF CORPORATION; a graft polymer having an anionic functional group in the stem polymer part and a polyoxyalkylene chain in the branch part (graft chain); polyoxyalkylene chain Medium length, Mw = 16,000 or more and 20,000 or less), processing accelerator,
-Compound C: Marialim (registered trademark) SC0708A (manufactured by NOF CORPORATION; a graft polymer having an anionic functional group in the stem polymer part and a polyoxyalkylene chain in the branch part (graft chain); polyoxyalkylene chain Medium length, Mw = 9,000 or more and 15,000 or less), processing accelerator,
Compound D: Marialim (registered trademark) SC1015F (manufactured by NOF CORPORATION; a graft polymer having an anionic functional group in the stem polymer part and a polyoxyalkylene chain in the branch part (graft chain); polyoxyalkylene chain. Longer, Mw = 10,000 or more and 15,000 or less), processing accelerator,
-Compound E: Polyacrylic acid (manufactured by Toagosei Chemical Co., Ltd .; Mw = 8,000 or more and 10,000 or less), comparative compound,
-Compound F: Polyacrylic acid (manufactured by Toagosei Chemical Co., Ltd .; Mw = 80,000 or more and 100,000 or less), comparative compound,
-Compound G: Polyacrylic acid (manufactured by Toagosei Chemical Co., Ltd .; Mw = 400,000 or more and 500,000 or less), a compound for comparison.

The weight average molecular weight (Mw) of the processing accelerator and the comparative compound is determined by gel permeation chromatography (GPC) using a GPC device (manufactured by Shimadzu Corporation, model: Polyethylene + ELSD detector (ELSD-LTII)). It was determined by using it in terms of polyethylene glycol. Specifically, it is as follows.

GPC device: manufactured by Shimadzu Corporation Model: Prominence + ELSD detector (ELSD-LTII)
Column: VP-ODS (manufactured by Shimadzu Corporation)
Mobile phase A: MeOH
B: 1% aqueous acetic acid flow rate: 1 mL / min Detector: ELSD temp. 40 ° C, Gain 8, N2GAS 350 kPa
Oven temperature: 40 ° C
Injection volume: 40 μL.

In the adjustment of the polishing composition, the pH value was confirmed by a pH meter (HORIBA, Ltd. model number: LAQUA (registered trademark)).

[Polishing speed]
The substrates S1 to S4 shown in Table 2 below were prepared as objects to be polished.

Subsequently, using the obtained polishing composition, the substrate was polished with the following polishing apparatus and polishing conditions, and the polishing speed of the substrate was evaluated according to the following method. The polishing results using the polishing compositions P1 to P19 are shown in Table 3 below. The polishing results using the polishing compositions P20 to P35 are shown in Table 4 below. In Table 4 below, the results of polishing using the polishing compositions P1, P5, P13, P15 and P17 are also shown for comparison with the polishing compositions P20 to P35.

(Polishing equipment and polishing conditions)
Polishing device: Small tabletop polishing machine (EJ380IN manufactured by Nippon Engis Co., Ltd.)
Polishing pad: Hard polyurethane pad (IC1000 manufactured by Nitta Haas Co., Ltd.)
Platen (surface plate) rotation speed: 70 [rpm]
Head (carrier) rotation speed: 70 [rpm]
Polishing pressure: 4.0 [psi]
Flow rate of polishing composition: 100 [ml / min]
Polishing time: 1 [min]
(Abrasion speed evaluation method)
1. 1. Using an electronic balance GH-202 (manufactured by A & D Co., Ltd.), the mass of the object to be polished before and after polishing was measured, and from these differences, the amount of change in the mass of the object to be polished before and after polishing ΔM [kg] ] Was calculated;
2. By dividing the mass change amount ΔM [kg] of the polishing object before and after polishing by the specific gravity of the polishing object (specific gravity of the material to be polished), the volume change amount ΔV [m ³ ] of the polishing object before and after polishing Was calculated;
3. 3. By dividing the volume change amount ΔV [m ³ ] of the polishing object ^{before and after polishing by the area S [m 2} ] of the polishing surface of the polishing object, the thickness change amount Δd [m] of the polishing object before and after polishing can be obtained. Calculated;
4. The amount of change in thickness Δd [m] of the object to be polished before and after polishing was divided by the polishing time t [min], and the unit was further converted to [μm / min]. This value was defined as the polishing rate v [μm / min].

From Table 3 above, it was confirmed that the polishing compositions P1 to P12 according to the present invention exhibited a high polishing rate. Further, it was confirmed that these polishing compositions exhibit an extremely high polishing rate when the material to be polished is a resin.

On the other hand, it was confirmed that the polishing compositions P13 to P19 according to the comparative example were inferior in polishing speed, and a high polishing speed could not be obtained even in resin polishing.

Further, from Table 4 above, the polishing compositions P20 to P26 according to the present invention, which further contain a processing accelerator, contain abrasive grains of the same type as these and do not contain a processing accelerator, and the polishing composition according to the present invention. It was confirmed that the polishing rate was higher than that of the products P1 and P27 to P29. Further, the polishing compositions P30 to P32 according to the present invention, which further contain a processing accelerator, are compared with the polishing composition P5 according to the present invention, which contains abrasive grains of the same type as these and does not contain a processing accelerator. It was confirmed that it showed a higher polishing rate. As described above, it was confirmed that the polishing composition according to the present invention exhibits a higher polishing rate by further containing a processing accelerator. Further, it was confirmed that these effects of improving the polishing rate became more remarkable when the material to be polished was a resin.

On the other hand, the polishing compositions P33 to P35 according to the comparative example, which further contain a processing accelerator, each contain abrasive grains of the same type as these and do not contain a processing accelerator, as compared with P13, P15 and P17. It was confirmed that the polishing speed was inferior and that the effect of improving the polishing speed by the processing accelerator could not be obtained.

This application is based on Japanese Patent Application No. 2019-165616 filed on September 11, 2019 and Japanese Patent Application No. 2020-048332 filed on March 18, 2020. , Incorporated as a whole by reference.

Claims (15)

1. Contains alumina particles and a dispersion medium,
   A polishing composition having a breaking strength of the alumina particles of 0.5 GPa or more.
2. The polishing composition according to claim 1, wherein the alumina particles are alumina particles produced by an explosive combustion method.
3. Contains alumina particles and a dispersion medium,
   A polishing composition in which the alumina particles are alumina particles produced by an explosive combustion method.
4. The polishing composition according to any one of claims 1 to 3, wherein the sphericity of the alumina particles exceeds 50%.
5. The polishing composition according to any one of claims 1 to 4, wherein the alumina particles contain a γ phase as a crystal phase.
6. The polishing composition according to any one of claims 1 to 5, wherein the pregelatinization rate of the alumina particles is less than 50%.
7. The polishing composition according to any one of claims 1 to 6, wherein the pH is 1 or more and 12 or less.
8. The polishing composition according to any one of claims 1 to 7, wherein the breaking strength of the alumina particles is 0.6 GPa or more.
9. The polishing composition according to any one of claims 1 to 8, wherein the breaking strength of the alumina particles is 2 GPa or less.
10. The polishing composition according to any one of claims 1 to 9, wherein the sphericity of the alumina particles is 99.9% or less.
11. The polishing composition according to any one of claims 1 to 10, further comprising a graft polymer having an anionic functional group in the trunk polymer portion.
12. The polishing composition according to any one of claims 1 to 11, which is used for polishing an object to be polished containing a resin on the polished surface.
13. Producing alumina particles by the explosion method and
    The alumina particles and the dispersion medium are mixed by stirring.
    The method for producing a polishing composition according to any one of claims 1 to 12.
14. Using the polishing composition according to any one of claims 1 to 12, or
    A polishing composition is produced by the production method according to claim 13, and the polishing composition is used to prepare the polishing composition.
    A polishing method for polishing an object to be polished.
15. The polishing method according to claim 14, wherein the polishing object is a polishing object containing a resin on the polishing surface.