JP6783609B2 - Metal oxide particle dispersion - Google Patents

Description

The present invention relates to a metal oxide particle dispersion liquid, a polishing liquid composition for a semiconductor substrate containing the dispersion liquid, a method for producing a semiconductor substrate using the polishing liquid composition, and a method for polishing a substrate.

CMP (Chemical Mechanical Polishing) technology is a method in which the surface of the substrate to be polished and the polishing pad are in contact with each other, and the polishing liquid composition is supplied to these contact sites while the substrate to be polished and the polishing pad are relative to each other. This is a technique for chemically reacting the surface uneven portion of the substrate to be polished and mechanically removing and flattening the surface uneven portion by moving the surface.

Currently, for example, in the manufacturing process of semiconductor devices, when flattening the interlayer insulating film, forming a shallow trench element separation structure (hereinafter, also referred to as "element separation structure"), forming a plug and embedded metal wiring, etc. , This CMP technology has become an indispensable technology. In recent years, the number of layers and high definition of semiconductor elements has dramatically increased, and there is a demand for further improvement in the yield and throughput (yield) of semiconductor elements. Along with this, further reduction of polishing scratches such as scratches has been desired in the CMP process, and in order to suppress the occurrence of polishing scratches, aggregation of polishing particles is suppressed and the polishing particles are dispersed. It needs to be in good condition.

Therefore, a polishing liquid composition containing a polishing aid that contributes to improving the dispersibility of polishing particles is disclosed. For example, Patent Document 1 contains water, abrasive fine particles, and a chelating agent as an abrasive liquid composition used for forming an element separation structure, and polyacrylic acid group or polymethacrylic acid group as an optional component. A polishing liquid composition containing a polishing aid containing the mixture is disclosed. Patent Documents 2 and 3 disclose a polishing liquid composition containing cerium oxide particles, water, a polishing aid such as ammonium polyacrylate, and dihydroxyethylglycine (DHEG). Patent Document 4 and Patent Document 5 describe a polishing liquid used for polishing a glass substrate for a magnetic disk or an aluminum substrate for a magnetic disk whose surface is nickel-phosphorus plated, in order to prevent precipitation of metal ions derived from equipment. A polishing solution containing a chelating agent and a neutralizing salt such as polyacrylic acid salt is disclosed. In Patent Documents 6 to 8, for the purpose of suppressing the occurrence of dishing by using cerium oxide particles in combination with a polymer compound having a carboxylic acid group or a carboxylic acid base, and further improving flatness, -COMM For CMPs containing organic acids (M is a metal atom such as H, NH ₄ , or Na, K) having anionic groups such as groups, Ph-OM groups, -SO ₃ M groups, and -PO ₃ M ₂ groups. The polishing liquid is disclosed. Patent Document 9 describes an abrasive used for polishing a silicon oxide film, which comprises cerium oxide particles, polyacrylic acid, a strong acid having a pKa of 3 or less, and a strong base having a pKa of 10 or more. The agent is disclosed. When polyacrylic acid is added to the polishing liquid composition used for polishing the silicon oxide film on the silicon nitride film, it is effective in suppressing the polishing of the silicon nitride film, and when added in a small amount, the dispersibility of the abrasive grain particles However, if the addition amount is increased in order to further enhance the polishing suppressing effect of the silicon nitride film, reaggregation of abrasive grain particles occurs, which causes polishing scratches such as scratches.

WO2001 / 80296 Japanese Unexamined Patent Publication No. 2007-318702 JP-A-2007-134696 Japanese Unexamined Patent Publication No. 2014-141667 Japanese Unexamined Patent Publication No. 2014-142987 Japanese Unexamined Patent Publication No. 2012-146974 Japanese Unexamined Patent Publication No. 2013-459944 Japanese Unexamined Patent Publication No. 2001-7060 Japanese Patent Application Laid-Open No. 2008-182179

However, in the metal oxide particle dispersion liquid, it is desired that the agglutination of the particles is further suppressed and the dispersed state of the particles is better.

Therefore, in the present invention, a metal oxide particle dispersion liquid in which agglomeration of particles is further suppressed and the dispersed state of the particles is better, a polishing liquid composition for a semiconductor substrate containing the dispersion liquid, and the polishing liquid composition A method for manufacturing a semiconductor substrate and a method for polishing the substrate using the above.

The metal oxide particle dispersion of the present invention is a water-soluble polymer B selected from metal oxide particles A, a polymer containing a structural unit derived from (meth) acrylic acid, and salts thereof, an aminocarboxylic acid, and an organic phosphonic acid. , And at least one compound C selected from these salts, and an aqueous medium.
The water-soluble polymer B is contained in an amount of 0.5 parts by mass or more and 5.0 parts by mass or less with respect to 1 part by mass of the metal oxide particles A.
It is a metal oxide particle dispersion liquid containing 0.1 part by mass or more and 1.5 parts by mass or less of the compound C with respect to 100 parts by mass of the water-soluble polymer B.

The polishing liquid composition for a semiconductor substrate of the present invention is a polishing liquid composition containing the metal oxide particle dispersion liquid of the present invention.

The method for manufacturing a semiconductor substrate of the present invention is a method for manufacturing a semiconductor substrate, which comprises a step of polishing the substrate to be polished using the polishing liquid composition for a semiconductor substrate of the present invention.

The method for polishing a substrate of the present invention includes a step of polishing the substrate to be polished using the polishing liquid composition for a semiconductor substrate of the present invention, and the substrate to be polished is a substrate to be polished used for manufacturing a semiconductor substrate. , Polishing method.

According to the present invention, in the metal oxide particle dispersion liquid, aggregation of the metal oxide particles can be suppressed, and the dispersed state of the metal oxide particles can be improved. Therefore, if the substrate to be polished is polished using the polishing liquid composition containing the metal oxide particle dispersion liquid of the present invention, polishing scratches such as scratches can be expected to be reduced.

In the present invention, a water-soluble polymer B containing a metal oxide particle A (hereinafter sometimes abbreviated as “particle A”) and a structural unit derived from (meth) acrylic acid (hereinafter abbreviated as “polymer B”). In a metal oxide particle dispersion containing, and an aqueous medium, at least one compound C selected from aminocarboxylic acid and organic phosphonic acid is contained, and the mass ratio of the particle A to the polymer B and It is based on the finding that the aggregation of particles can be suppressed and the dispersed state of the particles A can be improved by setting the mass ratio of the water-soluble polymer B and the compound C to a value in a specific range.

The details of the mechanism of effect manifestation of the present invention are not clear, but it is estimated as follows. However, these are estimates, and the present invention is not limited to these mechanisms.

In the metal oxide particle dispersion liquid of the present invention (hereinafter, may be abbreviated as "particle dispersion liquid"), since the polymer B is contained in a specific mass ratio with respect to the particle A, the height to the particle A is high. Compound C, which is considered to have high compatibility with the polymer B, is highly compatible with the compound B, which suppresses excessive adsorption of the molecule B, is easier to disperse than the polymer B, can be adsorbed to the particles A by a chelating action, and is highly compatible with the polymer B. It is contained in a specific mass ratio with respect to the molecule B. Therefore, excessive adsorption of the polymer B to the particles A is prevented, and as a result, bridging aggregation caused by the entanglement of the polymers B and the discharge of the polymer between the particles causes a polymer depleted region. It is possible to suppress depletion aggregation in which particles aggregate with each other. Therefore, it is presumed that in the metal oxide particle dispersion liquid of the present invention, the aggregation of particles is suppressed and the dispersed state of the particles can be improved.

Further, under almost neutral conditions, the surface of the silicon oxide film is negatively charged and hydrophilic, while the surface of the silicon nitride film is zero or slightly positively charged and slightly hydrophobic. is there. The polymer B contained in the particle dispersion of the present invention has less dissociation of carboxylic acid in the constituent unit, exhibits appropriate hydrophobicity, and has an anionic and negatively charged carboxylic acid group. doing. Therefore, the polymer B easily approaches and adsorbs the silicon nitride film. Therefore, when the polishing of the silicon oxide film which is the film to be polished progresses and the silicon nitride film which is the polishing stopper film is exposed, the polymer B becomes a silicon nitride film by both hydrophobic interaction and charge interaction. Selectively adsorb to. Therefore, the polishing liquid composition for a semiconductor substrate of the present invention (hereinafter, may be abbreviated as "polishing liquid composition") containing the particle dispersion liquid of the present invention is used to polish, for example, a silicon oxide film on a silicon nitride film. When used for this purpose, the polishing of the silicon nitride film is suppressed by the presence of the film of the polymer B adsorbed on the silicon nitride film, so that the polishing of the silicon nitride film can be suppressed and the polishing of the silicon oxide film can proceed. it can. Therefore, if the polishing liquid composition of the present invention is used in a method for producing a semiconductor substrate, for example, in a step of forming an element separation structure, it is possible to suppress the occurrence of polishing scratches on the silicon nitride film. Therefore, in the present invention, the silicon oxide film is used. And a silicon nitride film are included, and a highly smooth surface can be obtained.

The particle dispersion of the present invention contains particles A, a polymer B, a compound C, and an aqueous medium. In the particle dispersion of the present invention, the mass ratio of the polymer B to 1 part by mass of the particles A is 0.5 parts by mass or more and 5.0 parts by mass or less, and the mass of the compound C to 100 parts by mass of the polymer B. The ratio is 0.1 parts by mass or more and 1.5 parts by mass or less.

Among the particle dispersions of the present invention, one aspect of the particle dispersion of the present invention, which is preferably used for polishing, will be described in detail below.

[Metal oxide particles A]
The particle dispersion of the present embodiment contains particles A as abrasive grains. The particles A are preferably cerium oxide particles, silicon oxide particles having at least a part of the surface coated with cerium oxide, silicon oxide particles, and oxidation from the viewpoint of chemical stability and hardness of the particles in polishing a semiconductor substrate. At least one selected from zirconium particles, cerium oxide particles doped with zirconium oxide, aluminum oxide particles, and titanium oxide particles. When the object to be polished is a film containing silicon such as a silicon oxide film, cerium oxide particles and silicon oxide having at least a part of the surface coated with granular cerium oxide are preferable from the viewpoint of polishing using CMP technology. At least one selected from particles and cerium oxide particles doped with zirconium oxide, more preferably at least one selected from cerium oxide particles and silicon oxide particles having at least a part of the surface coated with granular cerium oxide. It is more preferably cerium oxide particles.

Cerium oxide particles can be produced, for example, by a sedimentation method. As the sedimentation method, for example, the method described in JP-A-2010-505735 can be adopted. Silicon oxide particles having at least a part of the surface coated with cerium oxide can be produced by the method described in JP-A-2015-2321029 and the like. Cerium oxide particles doped with zirconium oxide can be produced by the method described in JP-A-2010-16064.

The average primary particle size of the particles A is preferably 15 nm or more, more preferably 20 nm or more, still more preferably 40 nm or more from the viewpoint of ensuring a high polishing rate of the silicon oxide film, and from the viewpoint of suppressing the occurrence of polishing scratches. Therefore, it is preferably 300 nm or less, more preferably 200 nm or less, and further preferably 150 nm or less. In the present invention, the average primary particle size of the particles A is calculated using the BET specific surface area S (m ² / g) calculated by the BET (nitrogen adsorption) method. The BET specific surface area can be measured by the method described in Examples.

The content of the particles A in the particle dispersion of the present embodiment is preferably 0.001% by mass or more, more preferably 0., from the viewpoint of ensuring a high polishing rate of the silicon oxide film and suppressing polishing of the silicon nitride film. It is 01% by mass or more, more preferably 0.05% by mass or more, and preferably 1.0% by mass or less, more preferably 0.80% by mass or less, still more preferably 0.60% by mass or less.

[Water-soluble polymer B]
The particle dispersion liquid of the present embodiment contains a water-soluble polymer B selected from a polymer containing a structural unit derived from (meth) acrylic acid and a salt thereof from the viewpoint of improving the dispersion stability of the particles A. Here, "water-soluble" means having a solubility of 2 g / 100 mL or more in water (20 ° C.). The aqueous polymer may be in an unneutralized state or in an alkali-neutralized state.

From the viewpoint of improving the dispersion stability of the particles A, the polymer B is preferably polyacrylic acid, polymethacrylic acid, a copolymer of (meth) acrylic acid and a sulfonic acid having a vinyl group, or (meth) acrylic. It is a copolymer of acrylic acid having an acid and a vinyl group, and at least one selected from these salts. The sulfonic acid having a vinyl group is preferably styrene sulfonic acid from the viewpoint of reducing polishing scratches, and the phosphoric acid having a vinyl group is preferably 2- (methacryloyloxy) ethyl phosphate. The salt is preferably at least one selected from an alkali metal salt, an ammonium salt, and an amine salt, and more preferably an ammonium salt. Among these, the polymer B is more preferably at least one selected from polyacrylic acid and polyacrylic acid salt from the viewpoint of improving the dispersion stability of the particles A, and further preferably polyacrylic acid. It is a salt, and even more preferably ammonium polyacrylate. When the particle dispersion liquid of the present invention is used in the step of forming the device separation structure, polishing of a stopper film such as a silicon nitride film can be suppressed and polishing scratches can be reduced. The (meth) acrylic acid refers to at least one selected from acrylic acid and methacrylic acid.

Examples of the counterion when the polymer B takes the form of a salt include a metal ion, an ammonium ion, an alkylammonium ion, an alkylamine ion and the like, and the metal ion is preferably an alkali metal ion. , More preferably, at least one of K ion and Na ion. The counterion is preferably at least one of K ion, Na ion, and ammonium ion, and more preferably ammonium, from the viewpoint of suppressing polishing of the silicon nitride film and ensuring a high polishing rate of the silicon oxide film. It is an ion.

The molar ratio of (meth) acrylic acid to sulfonic acid having a vinyl group used in the synthesis of a copolymer of (meth) acrylic acid and a sulfonic acid having a vinyl group (the number of moles of (meth) acrylic acid / having a vinyl group) The number of moles of sulfonic acid) is preferably (60/40) or more, more preferably (70/30) or more, and even more preferably, from the viewpoint of suppressing polishing of the silicon nitride film and ensuring a high polishing rate of the silicon oxide film. Is (80/20) or more, even more preferably (85/15) or more, and preferably (98/2) or less, more preferably (95/5) or less, even more preferably (92.5). /7.5) or less, and even more preferably (91/9) or less. When the ratio of (meth) acrylic acid is large, the polishing inhibitory effect of the silicon nitride film is excellent, and when the amount of sulfonic acid having a vinyl group is large, a high polishing rate of the silicon oxide film can be secured. The molar ratio is also the molar ratio of the structural unit derived from (meth) acrylic acid contained in one molecule of the copolymer and the structural unit derived from sulfonic acid having a vinyl group.

The weight average molecular weight (Mw) of the polymer B is preferably 1,000 or more, more preferably 2,000 or more, still more preferably 2,000 or more, from the viewpoint of suppressing polishing of the silicon nitride film and ensuring a high polishing rate of the silicon oxide film. It is 5,000 or more, and preferably 100,000 or less, more preferably 50,000 or less, still more preferably 30,000 or less, and even more preferably 25,000 or less. When the weight average molecular weight is large, the polishing inhibitory effect of the silicon nitride film is excellent, and when the weight average molecular weight is small, a high polishing rate of the silicon oxide film can be secured. The weight average molecular weight (Mw) of the copolymer is a value measured by the following method.

In the present invention, the weight average molecular weight of the polymer B is determined by gel permeation chromatography (GPC) under the following conditions using liquid chromatography (manufactured by Hitachi, Ltd., L-6000 type high performance liquid chromatography). Can be measured.
Detector: Shodex RI SE-61 Differential Refractometer Detector Column: G4000PWXL and G2500PWXL manufactured by Tosoh Corporation were connected in series.
Eluent: 0.2 M phosphate buffer / acetonitrile = 90/10 (volume ratio) adjusted to a concentration of 0.5 g / 100 mL, and 20 μL was used.
Column temperature: 40 ° C
Flow velocity: 1.0 mL / min
Standard Polymer: Monodisperse polyethylene glycol with known weight average molecular weight

The content of the polymer B in the particle dispersion of the present embodiment is 0.5 parts by mass or more, preferably 0.75 parts by mass or more from the viewpoint of the polishing suppressing effect of the silicon nitride film with respect to 1 part by mass of the particles A. It is 5 parts by mass or more, more preferably 1.0 part by mass or more, and from the viewpoint of ensuring a high polishing rate of the silicon oxide film, 5.0 parts by mass or less, preferably 4.5 parts by mass or less, still more preferably. It is 4.0 parts by mass or less.

The content of the polymer B in the particle dispersion of the present embodiment is preferably 0.3 mass from the viewpoint of ensuring a high polishing rate of the silicon oxide film, suppressing polishing of the silicon nitride film, and reducing residual abrasive grains. % Or more, more preferably 0.4% by mass or more, still more preferably 0.5% by mass or more, and preferably 5.0% by mass or less, more preferably 4.0% by mass or less, still more preferably 3. It is 0.0% by mass or less.

[Compound C]
The particle dispersion of the present embodiment contains at least one compound C selected from aminocarboxylic acids, organic phosphonic acids, and salts thereof from the viewpoint of improving the dispersion stability of the particles A. From the viewpoint of improving the dispersion stability of the particles A, the compound C contains, for example, glutamate, picolinic acid, aspartic acid, diethylenetriamine pentaacetic acid (DTPA), hydroxyethylethylenediamine triacetic acid (HEDTA), and dihydroxyethyl. Glycine (DHEG) is mentioned, and examples of the organic phosphonic acid include 2-aminoethylphosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), aminotrimethylenephosphonic acid (AMPP), and ethylenediaminetetramethylenephosphonic acid. (EDTMP), diethylenetriaminepenta (methylenephosphonic acid), ethane-1,1-diphosphonic acid, ethane-1,1,2-triphosphonic acid, ethane-1-hydroxy-1,1-diphosphonic acid, ethane-1-hydroxy -1,1,2-triphosphonic acid, ethane-1,2-dicarboxy-1,2-diphosphonic acid, methanehydroxyphosphonic acid, 2-phosphonobutane-1,2-dicarboxylic acid, 1-phosphonobutane-2,3 Examples thereof include 4-tricarboxylic acid (PBTC) and α-methylphosphonosuccinic acid.

Examples of salts of aminocarboxylic acids and organic phosphonic acids include salts with metals, ammonia and alkylamines. Specific examples of the metal include metals belonging to Group 1A, 1B, 2A, 2B, 3A, 3B, 4A, 6A, 7A or Group 8 of the periodic table (long-period type). From the viewpoint of reducing scratches, ammonia or a metal belonging to Group 1A is preferable.

These compounds can be used alone or in combination of two or more. Compound C is more preferably hydroxyethylidene (1,1-diphosphonic acid) (HEDP), aminotrimethylenephosphonic acid (AMPP), 2-phosphonobutane-1,2 from the viewpoint of improving the dispersion stability of particle A. , 4-Tricarboxylic acid (PBTC), ethylenediaminetetramethylenephosphonic acid (EDTMP), ethylenediaminetetraacetic acid, nitrilotriacetic acid, diethylenetriaminetetraacetic acid (DTPA), N- (2-hydroxyethyl) ethylenediamine-N, N', N' -Triacetic acid (HEDTA), triethylenetetraminehexacetic acid, 1,3-propanediaminetetraacetic acid, 1,3-diamino-2-propanol-N, N, N', N'-tetraacetic acid, N- (2-) It is at least one selected from hydroxyethyl) iminodiacetic acid, dihydroxyethylglycine (DHEG), glycol etherdiaminetetraacetic acid, and salts thereof, and more preferably hydroxyethylidene (1,1-diphosphonic acid) (HEDP). , Ethylenediaminetetramethylenephosphonic acid (EDTMP), aminotrimethylenephosphonic acid (ATMP), 2-phosphonobutane-1,2,4 tricarboxylic acid (PBTC), diethylenetriaminetetraacetic acid (DTPA), hydroxyethylethylenediaminetriacetic acid (HEDTA), One or more selected from dihydroxyethylglycine (DHEG) and salts thereof, more preferably 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) and one or more selected from salts thereof. ..

The content of the compound C in the particle dispersion of the present embodiment is preferably 0.2 parts by mass or more, more preferably 0.2 parts by mass or more, with respect to 100 parts by mass of the particles A, from the viewpoint of improving the dispersion stability of the particles A. Is 0.4 parts by mass or more, more preferably 0.6 parts by mass or more, and from the viewpoint of ensuring a high polishing rate of the silicon oxide film, preferably 3.0 parts by mass or less, preferably 2.0 parts by mass. Hereinafter, it is more preferably 1.5 parts by mass or less.

The content of the compound C in the particle dispersion of the present embodiment is 0.1 part by mass or more, preferably 0.% by mass, with respect to 100 parts by mass of the polymer B from the viewpoint of improving the dispersion stability of the particles A. 2 parts by mass or more, more preferably 0.3 parts by mass or more, and from the viewpoint of ensuring a high polishing rate of the silicon oxide film, 1.5 parts by mass or less, preferably 1.0 part by mass or less, still more preferable. Is 0.8 parts by mass or less.

The content of the compound C in the particle dispersion liquid of the present embodiment is preferably 0.001% by mass or more, more preferably 0.002% by mass or more, and further preferably 0, from the viewpoint of improving the dispersion stability of the particles A. It is .003% by mass or more, and preferably 0.015% by mass or less, more preferably 0.01% by mass or less, still more preferably 0.008% by mass or less.

[Aqueous medium]
The particle dispersion of this embodiment contains an aqueous medium as a medium. Examples of the aqueous medium include water and a mixture of water and a solvent soluble in water. Examples of the solvent soluble in water include lower alcohols such as methanol, ethanol and isopropanol, and ethanol is preferable from the viewpoint of safety in the polishing step. From the viewpoint of improving the quality of the semiconductor substrate, the water-based medium is more preferably composed of water such as ion-exchanged water, distilled water, and ultrapure water. The content of the aqueous medium in the particle dispersion of the present invention is the particles, assuming that the total mass of the particles A, the polymer B, the compound C, the following optional components added as necessary, and the aqueous medium is 100% by mass. It can be the residue after removing A, polymer B, compound C and optional components.

[Arbitrary component]
The particle dispersion of the present embodiment may contain an arbitrary component as long as the effect of ensuring a high polishing rate of the silicon oxide film and suppressing polishing of the silicon nitride film is not impaired. Examples of the optional component include a pH adjuster, a polishing aid other than the polymer B, and the like. Further, examples of the optional component include a thickener, a rust preventive, a basic substance, a polishing rate improver, a surfactant and the like. The content of these optional components is preferably 0.001% by mass or more, more preferably 0.0025% by mass or more, further preferably 0.01% by mass or more, and silicon oxide from the viewpoint of suppressing polishing of the silicon nitride film. From the viewpoint of ensuring a high polishing rate of the film, 1% by mass or less is preferable, 0.5% by mass or less is more preferable, and 0.1% by mass or less is further preferable.

Examples of the pH adjuster include acidic compounds and alkaline compounds. Examples of the acidic compound include inorganic acids such as hydrochloric acid, nitric acid and sulfuric acid; and organic acids such as acetic acid, oxalic acid, citric acid and malic acid. Among them, from the viewpoint of versatility, at least one selected from hydrochloric acid, nitric acid and acetic acid is preferable, and at least one selected from hydrochloric acid and acetic acid is more preferable. Examples of the alkaline compound include inorganic alkaline compounds such as ammonia and potassium hydroxide; and organic alkaline compounds such as alkylamine and alkanolamine. Among them, at least one selected from ammonia and alkylamine is preferable, and ammonia is more preferable, from the viewpoint of improving the quality of the semiconductor substrate.

Examples of the polishing aid other than the polymer B include anionic surfactants and nonionic surfactants. Examples of the anionic surfactant include alkyl ether acetate, alkyl ether phosphate, and alkyl ether sulfate. Examples of the nonionic surfactant include nonionic polymers such as polyacrylamide, polyoxyalkylene alkyl ether and the like.

[Particle dispersion]
The pH of the particle dispersion of the present embodiment is preferably 2.5 or more, more preferably 3.0 or more, still more preferably 3 from the viewpoint of ensuring a high polishing rate of the silicon oxide film and suppressing polishing of the silicon nitride film. 5.5 or more, even more preferably 4.0 or more, even more preferably 5.5 or more, and preferably 8.5 or less, more preferably 8.0 or less, even more preferably 7.5 or less. .. In the present disclosure, the pH of the polishing liquid composition is a value at 25 ° C., which is a value measured using a pH meter. Specifically, the pH of the polishing liquid composition in the present disclosure can be measured by the method described in Examples.

The embodiment of the particle dispersion may be a so-called one-component type in which all the components are premixed and supplied to the market, or a so-called two-component type in which all the components are mixed at the time of use. .. The two-component particle dispersion is divided into a first solution and a second solution, and the particle dispersion contains, for example, a first solution in which particles A are mixed in an aqueous medium, a polymer B, and a compound C. It may be composed of a second liquid dissolved in an aqueous medium, and the first liquid and the second liquid may be mixed. The first liquid and the second liquid may be mixed before being supplied to the surface to be polished, or they may be supplied separately and mixed on the surface of the substrate to be polished. The first liquid and the second liquid may each contain an optional component, if necessary.

The content of each component in the above-mentioned particle dispersion is a content suitable when the particle dispersion is used as it is for polishing the substrate to be polished. However, the particle dispersion of the present embodiment may be stored and supplied in a concentrated state as long as its stability is not impaired. In this case, it is preferable in that the manufacturing / transportation cost can be reduced. Then, this concentrated solution can be appropriately diluted with the above-mentioned aqueous medium and used in the polishing step, if necessary. The dilution ratio is preferably 5 to 100 times.

[Manufacturing method of particle dispersion]
The particle dispersion of the present embodiment is produced by, for example, a production method including a step of blending a slurry containing particles A and an aqueous medium with a polymer B, compound C, and if necessary, other optional components by a known method. Can be manufactured. For example, the particle dispersion of the present embodiment is formed by blending particles A, an aqueous medium, a polymer B, a compound C, and if necessary, other optional components. In the present application, "blending" includes mixing a slurry containing particles A and an aqueous medium with polymer B, compound C, and, if necessary, other optional components simultaneously or sequentially. The mixing order is unlimited. From the viewpoint of improving the dispersion stability of the particles A, the step preferably prepares an additive solution containing the polymer B, the compound C, and an aqueous medium, and then prepares the additive solution into a slurry containing the particles A and the aqueous medium. This includes mixing, more preferably, a compound-containing solution in which compound C is dissolved in an aqueous medium and a polymer aqueous solution in which polymer B is dissolved in an aqueous medium are mixed to prepare an additive solution. Includes mixing in a slurry containing particles A and an aqueous medium.

Therefore, a preferred example of the method for producing a particle dispersion of the present invention is an additive solution obtained by mixing a compound-containing solution in which compound C is dissolved in an aqueous medium and a polymer aqueous solution in which polymer B is dissolved in an aqueous medium. After preparing the above, the step of mixing this with the slurry containing the particles A and the aqueous medium is included.

The compounding can be performed using, for example, a mixer such as a homomixer, a homogenizer, an ultrasonic disperser, and a wet ball mill. The blending amount of each component in the method for producing the particle dispersion liquid of the present embodiment can be the same as the content of each component of the particle dispersion liquid of the present embodiment described above.

From the viewpoint of economy, the content of the polymer B in the aqueous polymer solution is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and handleability. From the viewpoint, it is preferably 60% by mass or less, more preferably 55% by mass or less, and further preferably 50% by mass or less.

From the viewpoint of economy, the content of the polymer B in the additive solution is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and handleability. From the viewpoint, it is preferably 60% by mass or less, more preferably 55% by mass or less, and further preferably 50% by mass or less.

The viscosity of the additive solution at 25 ° C. is not particularly limited, but is preferably 150 mPa / s or less, more preferably 130 mPa / s or less, still more preferably 120 mPa / s or less in consideration of handleability.

The content of the compound C in the additive solution is preferably 0.1 part by mass or more, more preferably 0. By mass, from the viewpoint of improving the dispersion stability of the particles A with respect to 100 parts by mass of the polymer B. 2 parts by mass or more, more preferably 0.3 parts by mass or more, and preferably 1.5 parts by mass or less, more preferably 1 from the viewpoint of ensuring a high polishing rate of the silicon oxide film to be polished. It is 0.0 parts by mass or less, more preferably 0.8 parts by mass or less.

[Abrasive liquid composition for semiconductor substrates]
One aspect of the present invention is a polishing liquid composition for a semiconductor substrate, and the above-mentioned particle dispersion liquid of the present invention is diluted with an aqueous medium as it is, or other components are added to the polishing liquid composition. It can be used as a material for polishing the substrate to be polished. The substrate to be polished is, for example, a substrate used for manufacturing a semiconductor substrate. The dilution ratio is preferably 5 to 100 times.

[Abrasive liquid kit]
The present invention relates to a kit for producing a polishing liquid composition for a semiconductor substrate, wherein the dispersion liquid containing the particles A contains the particle A dispersion liquid in a container contained in a container. The polishing liquid kit of the present invention is housed in a container separate from the particle A dispersion liquid in the container, and can further contain an additive solution containing the polymer B, compound C, and an aqueous solvent. According to the present invention, it is possible to provide a polishing liquid kit capable of obtaining a polishing liquid composition for a semiconductor substrate capable of ensuring a high polishing speed of a silicon oxide film and suppressing polishing of a silicon nitride film.

The polishing solution kit of the present invention includes, for example, a slurry in which the particles A are dispersed in an aqueous medium (first solution) and an additive solution in which the polymer B and the compound C are dissolved in an aqueous medium (second solution). Examples thereof include a polishing liquid kit (two-component polishing liquid composition) in which the particles are stored in separate containers in a state where they are not mixed with each other and these are mixed at the time of use. The first liquid and the second liquid may each contain one or more selected from the above optional components and the above other components.

From the viewpoint of economy, the content of the polymer B in the second liquid is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and is easy to handle. From the viewpoint, it is preferably 60% by mass or less, more preferably 55% by mass or less, and further preferably 50% by mass or less.

The content of the compound C in the second liquid is preferably 0.1 part by mass or more, more preferably 0. By mass, from the viewpoint of improving the dispersion stability of the particles A with respect to 100 parts by mass of the polymer B. 2 parts by mass or more, more preferably 0.3 parts by mass or more, and preferably 1.5 parts by mass or less, more preferably 1 from the viewpoint of ensuring a high polishing rate of the silicon oxide film to be polished. It is 0.0 parts by mass or less, more preferably 0.8 parts by mass or less.

[Film to be polished]
Examples of the film to be polished by the polishing liquid composition for a semiconductor substrate of the present invention include a silicon oxide film. Therefore, the polishing liquid composition and the particle dispersion liquid of the present invention can be suitably used for polishing performed in the step of forming the element separation structure of the semiconductor substrate.

[Manufacturing method of semiconductor substrate]
The method for producing a semiconductor substrate of the present invention is a step of polishing a film to be polished using the polishing liquid composition for a semiconductor substrate of the present invention (hereinafter, also referred to as a “polishing step using the polishing liquid composition of the present invention”). The present invention relates to a method for manufacturing a semiconductor substrate (hereinafter, also referred to as “method for manufacturing a semiconductor substrate of the present invention”). In the method for manufacturing a semiconductor substrate of the present invention, for example, in the step of polishing the substrate to be polished, the silicon oxide film on the silicon nitride film is polished. According to an example of the method for manufacturing a semiconductor substrate of the present invention, polishing of the silicon nitride film in the polishing step can be satisfactorily suppressed and the occurrence of polishing scratches can be suppressed, so that a semiconductor substrate with improved substrate quality can be efficiently manufactured. The effect of being able to do it can be achieved.

As a specific example of the method for manufacturing a semiconductor substrate of the present invention, first, a silicon dioxide layer is grown on the surface of a silicon substrate by exposing it to oxygen in an oxidation furnace, and then silicon nitride (Si _{3) is} placed on the silicon dioxide layer. N ₄ ) A polishing stopper film such as a film is formed by, for example, a CVD method (chemical vapor deposition method). Next, a photolithography technique is applied to a substrate including a silicon substrate and a polishing stopper film arranged on one main surface side of the silicon substrate, for example, a substrate in which a polishing stopper film is formed on a silicon dioxide layer of a silicon substrate. Is used to form a trench. Next, for example, by a CVD method using silane gas and oxygen gas, a silicon oxide (SiO ₂ ) film which is a film to be polished for trench embedding is formed, and the polishing stopper film is covered with the film to be polished (silicon oxide film). Obtain a substrate to be polished. By forming the silicon oxide film, the trench is filled with silicon oxide of the silicon oxide film, and the opposite surface of the polishing stopper film on the silicon substrate side is covered with the silicon oxide film. The opposite surface of the surface of the silicon oxide film thus formed on the silicon substrate side has a step formed corresponding to the unevenness of the lower layer. Next, the silicon oxide film is polished by the CMP method until at least the opposite surface of the polishing stopper film on the silicon substrate side is exposed, and more preferably, the surface of the silicon oxide film and the surface of the polishing stopper film are flush with each other. Polish the silicon oxide film until The polishing liquid composition for a semiconductor substrate of the present invention can be suitably used in the step of performing polishing by this CMP method.

In polishing by the CMP method, the substrate to be polished and the polishing pad are relatively moved while the polishing liquid composition of the present invention is supplied to these contact sites in a state where the surface of the substrate to be polished is in contact with the polishing pad. As a result, the uneven portion on the surface of the substrate to be polished is flattened. In the above specific example of the method for manufacturing a semiconductor substrate of the present invention, another insulating film may be formed between the silicon dioxide layer of the silicon substrate and the polishing stopper film, or the silicon oxide film which is the film to be polished may be formed. Another insulating film may be formed between the polishing stopper film and the polishing stopper film.

In the polishing step using the polishing liquid composition of the present invention, the polishing pad was provided with a polishing pad having a rotation speed of, for example, 30 to 200 r / min, and a substrate to be polished having a rotation speed of, for example, 30 to 200 r / min. The polishing load set in the polishing apparatus can be set to, for example, 20 to 500 g weight / cm ² , and the supply speed of the polishing liquid composition can be set to, for example, 10 to 500 mL / min or less. When the polishing liquid composition is a two-component polishing liquid composition, the polishing speeds of the film to be polished and the polishing stopper film can be adjusted by adjusting the supply rates (or amounts) of the first liquid and the second liquid, respectively. In addition, the polishing rate ratio (polishing selectivity) between the film to be polished and the polishing stopper film can be adjusted.

In the polishing step using the polishing liquid composition of the present invention, the polishing time is from the viewpoint of ensuring a high polishing rate of the film to be polished (for example, silicon oxide film) and suppressing polishing of the polishing stopper film (for example, silicon nitride film). Therefore, it is preferably 10 seconds or more, more preferably 20 seconds or more, and from the viewpoint of improving productivity, it is preferably 3 minutes or less, more preferably 2 minutes or less, still more preferably 1 minute or less.

[Polishing method]
The method for polishing a substrate of the present invention relates to a method for polishing a substrate (hereinafter, also referred to as “the polishing method of the present invention”), which includes a polishing step using the polishing liquid composition of the present invention. In the method of polishing a substrate of the present invention, for example, in the step of polishing the substrate to be polished, the silicon oxide film on the silicon nitride film is polished.

By using the polishing method of the present invention, it is possible to satisfactorily suppress polishing of the silicon nitride film in the polishing process and suppress the occurrence of polishing scratches, so that the productivity of the semiconductor substrate with improved substrate quality can be improved. The effect can be achieved. The specific polishing method and conditions can be the same as the above-described method for manufacturing the semiconductor substrate of the present invention.

<Synthesis of ammonium polyacrylate>
Ammonium polyacrylate was synthesized as the water-soluble polymer B1 used in the preparation of the polishing liquid compositions of Examples 1 to 13 and Comparative Examples 1 to 5 as follows.
796.75 g of deionized exchanged water was charged into a separable flask equipped with a reflux tube, a stirrer, a thermometer, and a nitrogen introduction tube, and the temperature was raised to 98 ° C. A solution prepared by dissolving 875.3 g of acrylic acid (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent, purity 98%) and 116 g of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent, purity 98%) as an initiator for 2 hours. The mixture was dropped over and polymerized while maintaining 98 ° C., and aging was carried out for 1 hour while maintaining 98 ° C. to obtain polyacrylic acid having a weight average molecular weight of 23000. This is cooled to 40 ° C, and while maintaining this temperature, 721.2 g of 28% -ammonia water (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent) is added dropwise over 1 hour to prepare ammonium polyacrylate with 100% neutralization. did. Then, the solid content concentration of the obtained aqueous solution of ammonium polyacrylate was measured. The solid content concentration was measured by weighing 10 g of an aqueous ammonium polyacrylate solution on a petri dish and drying it in a 110 ° C. dryer for 12 hours. Then, in order to make the solid content concentration of the aqueous solution of ammonium polyacrylate salt 40% by mass, deionized water was added to prepare an aqueous solution of ammonium polyacrylate salt having a predetermined concentration.

The weight average molecular weight of polyacrylic acid was measured by GPC (column: α-M + α-M eluent manufactured by Tosoh Corporation: 60 mmol / L H ₃ PO ₄ , 50 mmol / L LiBr / DMF).

<Preparation of polishing liquid composition>
[Example 1]
Deion-exchanged water: 900 g was added to 50 g of cerium oxide slurry (manufactured by Showa Denko, GPL-C1010, solid content concentration: 10%) to obtain 950 g of cerium oxide slurry liquid. As a compound-containing solution, 10 g of hydroxyethylidene (1,1 diphosphonic acid) (HEDP: manufactured by Killest, solid content concentration: 60% by mass) was neutralized by adding 0.8 g of 28% by mass ammonia water. Ammonia-neutralized solution of 40% by mass of hydroxyethylidene (1,1 diphosphonic acid) was prepared by adding deion-exchanged water to the mixture. 0.148 g of this was added to 100 g of the aqueous ammonium polyacrylate salt solution (solid content: 40% by mass) prepared above to prepare an additive solution (25 ° C. viscosity: 62.3 mPa / s). In the preparation of the additive solution, a uniform solution was obtained without any precipitates. 25.037 g of this additive solution is added to the above cerium oxide slurry solution, and deion-exchanged water is further added to make 1000 g. Cerium oxide concentration: 0.5% by mass, ammonium polyacrylate salt: 1.0% by mass, hydroxyethylidene (1,1) Ammonium salt of (diphosphonic acid): 0.0037% by mass The polishing solution composition of Example 1 was prepared.

[Example 2]
The polishing liquid composition of Example 2 was prepared in the same manner as in Example 1 except that the content of the ammonium polyacrylate salt, which is the water-soluble polymer B1, was changed.

[Examples 3 and 4]
The polishing solution compositions of Examples 3 and 4 were prepared in the same manner as in Example 1 except that the content of hydroxyethylidene (1,1 diphosphonic acid), which is compound C1, was changed.

[Examples 5 to 10]
Polishing solution compositions of Examples 5 to 10 were prepared in the same manner as in Example 1 except that compounds C2 to C7 were used instead of compound C1.

[Example 11]
The polishing liquid composition of Example 11 was prepared in the same manner as in Example 1 except that C1 and C3 were used as the two types of Compound C and the content of Compound C was changed.

[Example 12]
The polishing liquid composition of Example 12 was prepared in the same manner as in Example 1 except that zirconium oxide particles (TZ-3Y-E manufactured by Tosoh Corporation) were used as the particles A.

[Example 13]
The polishing liquid composition of Example 13 was prepared in the same manner as in Example 1 except that aluminum oxide particles (45% by mass slurry manufactured by Saint-Gobain) were used as the particles A.

[Comparative Example 1]
The polishing liquid composition of Comparative Example 1 was prepared in the same manner as in Example 1 except that the compound C was not contained.

[Comparative Example 2]
Comparative Example in the same manner as in Example 1 except that the content of the organic acid C with respect to the water-soluble polymer B exceeds 1.5 parts by mass with respect to 100 parts by mass of the water-soluble polymer B. The polishing liquid composition of 2 was prepared.

[Comparative Example 3]
Comparative Example 3 in the same manner as in Example 1 except that the content of the organic acid C with respect to the water-soluble polymer B is less than 0.1 parts by mass with respect to 100 parts by mass of the water-soluble polymer B. The polishing liquid composition of the above was prepared.

[Comparative Example 4]
The polishing liquid composition of Comparative Example 4 was prepared in the same manner as in Comparative Example 1 except that zirconium oxide particles (TZ-3Y-E manufactured by Tosoh Corporation) were used as the particles A.

[Comparative Example 5]
The polishing liquid composition of Comparative Example 5 was prepared in the same manner as in Comparative Example 1 except that aluminum oxide particles (45% by mass slurry manufactured by Saint-Gobain) were used as the particles A.

The details of the particles A used for preparing the polishing liquid compositions of Examples 1 to 13 and Comparative Examples 1 to 5 are as follows.
A1: Cerium oxide particles (average primary particle size 70.4 nm, BET specific surface area 11.84 m ² / g)
A2: Zirconium oxide particles (average primary particle size 66.0 nm, BET specific surface area 16 m ² / g)
A3: Aluminum oxide particles (average primary particle size 70.1 nm, BET specific surface area 21.4 m ² / g)

Details of the compounds C1 to C7 used for preparing the ammonia neutralizing solution of the compounds C1 to C7 used for preparing the polishing liquid compositions of Examples 1 to 13 and Comparative Examples 1 to 5 are as follows.
C1: HEDP: Hydroxyethylidene (1,1-diphosphonic acid)
C2: EDTMP: ethylenediaminetetramethylenephosphonic acid (powder)
C3: ATMP: Aminotrimethylenphosphonic acid (50% by mass water-soluble)
C4: PBTC: 2-phosphonobutane-1,2,4 tricarboxylic acid (50% by mass water-soluble)
C5: DTPA: Diethylenetriamine pentaacetic acid (powder)
C6: HEDTA: Hydroxyethylethylenediaminetriacetic acid (powder)
C7: DHEG: Dihydroxyethylglycine (powder)

<Physical properties of polishing liquid composition>
The pH of the polishing liquid composition, the particle size distribution by DSL, the average primary particle size of the particles, and the BET specific surface area of the particles were measured by the following methods.

(A) pH measurement of the polishing liquid composition The pH value of the polishing liquid composition at 25 ° C. is a value measured using a pH meter (Toa Denpa Kogyo Co., Ltd., HM-30G), and is applied to the particle dispersion of the electrode. It is a numerical value 1 minute after soaking.

(B) Particle size distribution measurement by DSL In the particle size distribution measurement by dynamic light scattering method (DLS), the polishing liquid composition was directly applied to a measuring device without being diluted. As the measuring device, a Zetasizer Nano ZS type manufactured by Malvern was used. It is necessary to set the refractive index at the time of measurement. Here, the refractive index is set to 2.10 for cerium oxide, 2.13 for zirconium oxide, and 1.77 for aluminum oxide. The measurement is carried out at room temperature, and the particle size (D50) corresponding to 50% volume accumulation from the smaller particle size side (also referred to as "volume average diameter") and 10% volume accumulation from the smaller particle size side. The particle size (D10) corresponding to the above, and the particle size (D90) having a volume accumulation of 90% were obtained from the side with the smaller particle size. By comparing these values, it was used as an index of dispersibility.

(C) Average primary particle size of particle A The average primary particle size (nm) of particle A uses the specific surface area S (m ² / g) obtained by the following BET (nitrogen adsorption) method, and the true density of cerium oxide particles. Was calculated as 7.2 g / cm ³ , the true density of zirconium oxide grains was 5.7 g / cm ³ , and the true density of aluminum oxide was 4.0 g / cm ³ .

(D) Method for measuring BET specific surface area of particle A The specific surface area was measured as follows. Particle A was finely pulverized in an agate mortar to obtain a sample (when particle A was a slurry, it was dried with hot air at 120 ° C. for 3 hours in advance to distill off the dispersion medium, and then the pulverization was performed. T.). Immediately before the measurement, the sample is dried in an atmosphere of 120 ° C. for 15 minutes, and then measured by the nitrogen adsorption method (BET method) using a specific surface area measuring device (Micromeritic automatic specific surface area measuring device Flowsorb III2305, manufactured by Shimadzu Corporation). did.

<Evaluation of polishing liquid composition>
[Measurement of polishing rate of silicon oxide film and silicon nitride film]
A silicon oxide chip having a size of 4 cm × 4 cm was cut out from a blanket wafer having a silicon oxide film having a thickness of 2000 nm formed on a Si substrate having a diameter of 200 mm by the TEOS-plasma CVD method to prepare a silicon oxide chip. Similarly, a silicon nitride chip having a size of 4 cm × 4 cm was cut out from a blanket wafer having a silicon nitride film having a thickness of 300 nm formed on a Si substrate having a diameter of 200 mm by a CVD method to prepare a silicon nitride chip as a test piece.

As the polishing device, a tabletop polishing device (MA-300 type) manufactured by Musashino Denshi Co., Ltd. was used. The above silicon oxide chip or silicon nitride chip is set in the holder to which the adsorption film is attached, and the polishing pad made of hard urethane is attached on a surface plate with a diameter of 300 mm (product number: IC-1000 / Sub400, manufactured by Nitta Hearth). The holder was placed on the polishing pad so that the silicon oxide film or the silicon nitride film faced each other, and a weight was placed on the holder so that the processing load was 29.4 kPa (300 g / cm ² ). While dropping the polishing liquid composition on the polishing pad at a rate of 50 mL / min, the surface plate and the holder were rotated in the same rotation direction at 90 rpm for 2 minutes to polish the silicon oxide film or the silicon nitride film. After polishing, it was washed with ultrapure water and dried, and the silicon oxide chip or silicon nitride chip was used as a measurement target by the optical interference type film thickness measuring device (Lambda Ace VM-1000, manufactured by Dainippon Screen) described later. ..

Before and after polishing, the film thickness of the silicon oxide film or the silicon nitride film was measured using a light interference type film thickness measuring device. The polishing rate of the silicon oxide film or the silicon nitride film was calculated by the following formula and is shown in Table 1 below.
Polishing rate of silicon oxide film (nm / min)
= [Silicon oxide film thickness before polishing (nm) -Silicon oxide film thickness after polishing (nm)] / Polishing time (minutes)
Polishing rate of silicon nitride film (nm / min)
= [Silicon nitride film thickness before polishing (nm) -Silicon nitride film thickness after polishing (nm)] / Polishing time (minutes)

As shown in Table 1, the polishing liquid compositions of Examples 1 to 13 have more suppressed aggregation of particles A than the polishing compositions of Comparative Examples 1 to 5, and the dispersibility of the particles A is good. is there.

As described above, the particle dispersion liquid of the present invention is useful in a method for producing a semiconductor substrate for high density or high integration.

Claims (11)

Metal oxide particles A, water-soluble polymer B selected from polymers containing a structural unit derived from (meth) acrylic acid and salts thereof, aminocarboxylic acid, organic phosphonic acid, and at least one selected from salts thereof. A metal oxide particle dispersion for polishing a semiconductor substrate, which contains the compound C of the above and an aqueous medium .
The metal oxide particles A are at least one selected from cerium oxide particles, silicon oxide particles coated with cerium oxide, zirconium oxide particles, cerium oxide particles doped with zirconium oxide, and aluminum oxide particles.
The water-soluble polymer B is contained in an amount of 0.5 parts by mass or more and 5.0 parts by mass or less with respect to 1 part by mass of the metal oxide particles A.
A metal oxide particle dispersion containing 0.1 parts by mass or more and 1.5 parts by mass or less of the compound C with respect to 100 parts by mass of the water-soluble polymer B. The compound C is hydroxyethylidene (1,1-diphosphonic acid), aminotri (methylenephosphonic acid), 2-phosphonobutane-1,2,4-tricarboxylic acid, ethylenediaminetetra (methylenephosphonic acid), ethylenediaminetetraacetic acid, nitrilotria. Acetic acid, diethylenetriaminetetraacetic acid, N- (2-hydroxyethyl) ethylenediamine-N, N', N'-triacetic acid, triethylenetetraminehexacetic acid, 1,3-propanediaminetetraacetic acid, 1,3-diamino-2- It is at least one selected from propanol-N, N, N', N'-tetraacetic acid, N- (2-hydroxyethyl) iminodiacetic acid, dihydroxyethylglycine, glycol etherdiaminetetraacetic acid, and salts thereof. The dispersion according to claim 1. The dispersion according to claim 1 or 2, wherein the water-soluble polymer B is an ammonium salt. The dispersion according to any one of claims 1 to 3, wherein the pH at 25 ° C. is 6 or more and 8 or less. The dispersion according to any one of claims 1 to 4, wherein the water-soluble polymer B has a weight average molecular weight of 1,000 or more and 100,000 or less. The dispersion according to any one of claims 1 to 5, wherein the content of the metal oxide particles A in the metal oxide particle dispersion is 0.001% by mass or more and 1.0% by mass or less. .. A polishing liquid composition for a semiconductor substrate, which contains the dispersion liquid according to any one of claims 1 to 6. A method for manufacturing a semiconductor substrate, which comprises a step of polishing the substrate to be polished using the polishing liquid composition for a semiconductor substrate according to claim 7. A method for polishing a substrate, which comprises a step of polishing the substrate to be polished using the polishing liquid composition for a semiconductor substrate according to claim 7, wherein the substrate to be polished is a substrate used for manufacturing a semiconductor substrate. A kit for producing the polishing liquid composition according to claim 7.
A first liquid containing the metal oxide particles A and the aqueous medium and stored in a container,
It contains the water-soluble polymer B, the compound C, and the aqueous medium, and contains a second liquid contained in a container different from the first liquid.
A polishing liquid kit in which the content of the compound C in the second liquid is 0.1 part by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the water-soluble polymer B. The polishing liquid kit according to claim 10, wherein the content of the water-soluble polymer B in the second liquid is 1% by mass or more and 60% by mass or less.