KR20040095615A - Abrasive slurry having high dispersion stability and manufacturing method for a substrate - Google Patents

Abstract

PURPOSE: Provided are a polishing agent slurry which is improved in dispersion stability for a long time, has a good re-dispersion and is free from an organic dispersant, and a method for preparing a substrate by using the slurry. CONSTITUTION: The polishing agent slurry comprises a polishing microparticle comprising at least one kind of oxide; a colloidal oxide microparticle having an average diameter smaller than that of the polishing microparticle; and a dispersing medium for dispersing the polishing microparticle and the colloidal oxide microparticle. Preferably the polishing microparticle has an average diameter (Dp) of 100-5,000 nm and the colloidal oxide microparticle has an average diameter (Dc) of 10-300 nm, and the ratio of Dp/Dc is 10 or less. Preferably the polishing microparticle is cerium oxide; the colloidal oxide microparticle is colloidal silica; and the dispersing medium is water or an aqueous dispersing medium mainly comprising water.

Description

Abrasive slurry having high dispersion stability and manufacturing method for a substrate

The present invention relates to an abrasive slurry having excellent dispersion stability, and is not particularly limited, but also includes photomask blanks, including surface polishing for planarizing the surface of a substrate performed in a semiconductor manufacturing process or an electrostatic chuck manufacturing process. The present invention relates to an abrasive slurry suitable for use in chemical mechanical polishing (hereinafter referred to as "CMP"), which is widely employed for polishing polishing surfaces such as glass disks and optical lenses.

For example, very high precision flatness is required for a substrate such as a silicon substrate used in a semiconductor manufacturing process or an aluminum substrate used in an electrostatic chuck manufacturing process, and as a technique for flattening the substrate surface that is the surface to be polished. CMP, which combines mechanical polishing with abrasive fine particles and chemical polishing with etching liquid, employs a planarization technique for highly planarizing the substrate surface without damaging the substrate surface.

As the abrasive used in such a planarization technique, cerium oxide (CeO ₂ ) and manganese dioxide (MnO ₂ ) having various sizes (average particle diameters) generally vary depending on the type of substrate to be polished, the processing speed required by the planarization technique, and the like. Various kinds of metal oxides such as precipitated silica, fumed silica, colloidal silica, silicon oxide (SiO ₂ ), and aluminum oxide such as fumed alumina and colloidal alumina (Al ₂ O ₃ ). A slurry obtained by dispersing abrasive fine particles in a dispersion medium such as water is used.

However, these abrasive fine particles have poor dispersion stability in the dispersion medium depending on the type and size thereof, and, for example, have relatively large specific gravity in the case of cerium oxide particles. Thus, cerium oxide particles are dispersed in the dispersion medium to prepare an abrasive slurry. If the particles are uniformly dispersed for a while after preparation, the cerium oxide particles begin to disperse in a relatively short time thereafter, and then settle and settle, causing the particles to coagulate, leading to a larger particle diameter and broader particle size distribution. This causes problems such as a change in processing speed with time and damage to the substrate surface.

For this reason, conventionally, in order to solve the problem of sedimentation and aggregation in such an abrasive slurry, for example, a redispersion process for stirring again immediately before use of the abrasive slurry to disperse the abrasive fine particles or agglomerating to a predetermined particle size Separation removal processing, etc. which filter and isolate | separate larger abnormal aggregated particle | grains are performed, and it has become a big burden in planarization processes, such as a board | substrate.

Therefore, some proposals have been made to solve the problem of sedimentation and aggregation of the abrasive slurry in the related art.

That is, a cerium oxide abrasive containing cerium oxide particles, a copolymer of ammonium acrylate salt and methyl acrylate, and water, which is difficult to settle, and which can be polished at high speed without damaging the surface to be polished, such as an SiO ₂ insulating film, has been proposed ( See Japanese Patent Laid-Open No. 2000-17195).

The dispersant contains at least one compound selected from a water-soluble organic polymer, a water-soluble anionic surfactant, a water-soluble nonionic surfactant, and a water-soluble amine, and has a maximum sedimentation rate of 1 µm / s or less, less settling, and less stirring. A cerium oxide abrasive is proposed which is easy to homogenize and which can be polished at high speed without damaging the surface to be polished, such as an SiO ₂ insulating film (see Japanese Patent Laid-Open No. 2001-138214).

Furthermore, cerium oxide particles, first polyacrylates in which more than 90% of all carboxyl groups of polyacrylic acid are neutralized with ammonia, second polyacrylates in which 15 to 50% of all carboxyl groups of polyacrylic acid are neutralized with ammonia, and water And a cerium oxide abrasive having a total content of the first polyacrylate salt and the second polyacrylate salt in the range of 0.15 to 1% by weight, good stability and not causing two-layer separation, coagulation sedimentation solidification, or viscosity change. See Japanese Patent Laid-Open No. 2002-353175).

However, for cerium oxide abrasives containing these dispersants, it is difficult to solve the problem of sedimentation and aggregation over a long period of one month or more, and to maintain a good redispersibility. Occurrences of blockages in the piping of the apparatus due to this are also shown, and there is a problem that these various problems cannot be completely solved.

In addition, all of these cerium oxide polishing agents contain relatively large amounts (0.1 to 5% by weight) of organic compounds such as water-soluble organic polymers, water-soluble anionic surfactants, water-soluble nonionic surfactants, and water-soluble amines as dispersants. In the waste liquid, there is a problem in that inorganic materials of cerium oxide particles and organic substances such as dispersants are mixed, which requires a great deal of effort and cost for the waste liquid treatment.

In addition, from the viewpoint of reducing the production cost and transportation cost of the abrasive slurry as much as possible, it is preferable to manufacture as high a concentration as possible at the time of production, and to dilute to a predetermined concentration during use, but it is a problem of sedimentation and aggregation. Is more likely to occur at higher concentrations, and further development of an abrasive slurry excellent in dispersion stability is desired.

Therefore, the present inventors have excellent dispersion stability over a long period of time, good redispersibility, and can solve the problem of sedimentation and aggregation as much as possible, and use in a dispersant free which does not use an organic dispersant at all is possible. As a result of earnestly examining the possible abrasive slurry, it has been found that by adding colloidal fine particles having an average particle diameter smaller than the abrasive fine particles as the colloidal oxide, the sedimentation and aggregation of the abrasive fine particles can be suppressed as much as possible.

Accordingly, an object of the present invention is to provide excellent dispersion stability over a long period of time, good redispersibility, and to solve the problem of sedimentation and aggregation as much as possible, and to be used in a dispersant free which does not use an organic dispersant at all. To provide an abrasive slurry.

In addition, another object of the present invention is to provide a substrate for producing industrially advantageous substrates such as silicon substrates used in the semiconductor manufacturing process by CMP and aluminum substrates used in the electrostatic chuck manufacturing process by using such abrasive slurry. It is to provide a manufacturing method.

That is, the present invention is an abrasive fine particles consisting of one or two or more oxides; Colloidal fine particles having a colloidal oxide having an average particle diameter smaller than that of the abrasive fine particles; A dispersion medium for dispersing these abrasive fine particles and colloidal fine particles; It relates to an abrasive slurry excellent in dispersion stability comprising a.

Moreover, this invention relates to the manufacturing method of a board | substrate including the grinding | polishing process of grind | polishing a board | substrate using said abrasive slurry as a method of manufacturing an inorganic board | substrate.

In the present invention, as the oxide used as the abrasive fine particles, those conventionally used as this kind of abrasive fine particles can be used as they are, and specifically, metal oxides such as cerium oxide (CeO ₂ ), manganese dioxide (MnO ₂ ), and sedimentation there may be mentioned silica, fumed silica, silicon oxide, such as colloidal silica (SiO ₂₎ or, fumed alumina, aluminum oxide, such as colloidal alumina (Al ₂ O ₃₎ or the like. These can be used individually by 1 type, and can also mix and use 2 or more types.

Among these oxides, those preferred for use as abrasive fine particles in the present invention are relatively high in specific gravity or relatively large in average particle diameter, such as, for example, cerium oxide particles and aluminum oxide particles. It is good to be easy and it is especially effective with respect to such abrasive fine particles.

There is no restriction | limiting in particular about the average particle diameter (Dp) of the abrasive microparticles | fine-particles used by this invention, Although it changes also with a kind, In the case of a cerium oxide particle, it is good that it is usually 100-5,000 nm, Preferably it is 500-2,000 nm, and polishing Depending on the type of fine particles, the polishing particle may not be sufficiently exhibited when the average particle diameter Dp is smaller than 100 nm. On the contrary, when the average particle diameter Dp is larger than 5,000 nm, scratches tend to occur on the polishing surface.

Moreover, about colloidal microparticles used with this abrasive microparticle, a colloidal oxide, such as colloidal silica and colloidal alumina, is mentioned, for example, These can use 2 or more types besides being able to use only 1 type alone. It can also mix and use.

In addition, the average particle diameter (Dc) of the colloidal fine particles needs to be at least smaller than the above-described abrasive fine particles, and varies depending on the type, but in many cases including the case of colloidal silica, usually 10 to 300 nm, preferably It is 20-200 nm, It is good that the particle diameter ratio (Dc / Dp) of the average particle diameter (Dp) of the said abrasive grain and the average particle diameter (Dc) of this colloidal microparticle is 10 or less, Preferably it is about 0.01-3. If the average particle diameter (Dc) of these colloidal fine particles is less than 10 nm, it is unstable at the time of manufacture, and it is easy to gelate. On the contrary, if it is larger than 300 nm, the particle size is easily varied and the particle size ratio (Dc / Dp) exceeds 10. As a result, the abrasive fine particles become too small and the polishing ability is not sufficiently exhibited.

In addition, the dispersion medium constituting the polishing slurry can be used as it is conventionally used in this type of polishing slurry, and is not particularly limited, and the use of the polishing slurry, for example, a silicon substrate used in a semiconductor manufacturing process, Abrasive slurry for CMP used for planarization of substrates such as aluminum substrates used in the electrostatic chuck manufacturing process, abrasive slurry for CMP used for polishing polishing surfaces such as photomask blanks, glass disks, and optical lenses; Although it can select suitably according to the application of the normal abrasive slurry etc. which are used for grinding of the other to-be-polished surface, Preferably it is water, or water based on methanol, ethanol, n-propanol, iso-propanol, n-butanol, tert- Alcohols such as butanol and water-soluble solvents such as ketones, esters and ethers The aqueous dispersion medium is used suitably. In addition, in this dispersion medium, etching liquid for chemical polishing at the time of CMP is added as needed, similar to the conventional case.

The particle concentration (Cp) of the abrasive fine particles constituting the abrasive slurry of the present invention varies depending on the type of abrasive fine particles, but in the case of cerium oxide particles, it is usually 5 to 40% by weight, preferably 5 to 30% by weight. More preferably, it is 5 to 10 weight%, and about the particle concentration (Cc) of colloidal microparticles, in many cases including colloidal silica, it is usually 0.1 to 5 weight%, Preferably it is 0.5 to 2 weight %, And the weight compounding ratio (Cc / Cp) of the abrasive fine particles and colloidal fine particles is preferably 1 or less, preferably 0.5 or less. The abrasive slurry prepared at such a particle concentration (Cp) and a particle concentration (Cc) may be at the particle concentration (Cp) and the particle concentration (Cc) as it is, or, if necessary, with a predetermined particle concentration (Cp) and particle concentration ( It is diluted to Cc) and used for grinding | polishing of CMP etc. If the particle concentration (Cp) of the abrasive fine particles is lower than 5% by weight, the polishing ability is insufficient. On the contrary, if the particle concentration (Cp) of the abrasive fine particles is higher than 40% by weight, solubility is caused. If the particle concentration (Cc) of the colloidal fine particles is lower than 0.1% by weight, the effect of inhibiting sedimentation and aggregation is lowered. On the contrary, if the particle concentration (Cc) of the colloidal fine particles is higher than 5% by weight, aggregation phenomenon tends to occur. Furthermore, when the weight compounding ratio (Cc / Cp) of the abrasive fine particles and colloidal fine particles exceeds 1, aggregation phenomenon tends to occur.

The abrasive slurry of the present invention has excellent dispersion stability over a long period of time even without adding organic dispersants such as water-soluble organic polymers, water-soluble anionic surfactants, water-soluble nonionic surfactants, and water-soluble amines, and has good redispersibility. · You can solve the problem of aggregation.

In addition, in the present invention, the method for preparing the abrasive slurry may be a slurry in which the abrasive particles, colloidal particles and dispersion medium which are constituents thereof are uniformly mixed, and the abrasive particles and colloidal particles are uniformly dispersed in the dispersion medium. . It does not specifically limit, In addition to being able to prepare using a normal stirrer, wet dispersers, such as an ultrasonic disperser, a homogenizer, a ball mill, a vibration ball mill, a planetary ball mill, a medium stirring mill, can be used as needed.

The abrasive slurry of the present invention is not only flattening a substrate such as a silicon substrate used in a semiconductor manufacturing process or an aluminum substrate used in an electrostatic chuck manufacturing process, but also an oxide film such as a silicon oxide insulating film formed on a wiring board having predetermined wiring, glass, silicon nitride, and the like. Such as an inorganic insulating film, an optical lens such as a photomask lens prism, an inorganic conductive film such as ITO, an optical integrated circuit, an optical switching element, an optical waveguide composed of glass and crystalline materials, an optical fiber cross section, a scintillator, etc. It is used to polish optical single crystals, solid laser single crystals, blue laser LED sapphire substrates, semiconductor single crystals such as SiC, GaP, GaAS, glass substrates for magnetic disks, magnetic heads, and the like.

For example, the unevenness of the surface of the oxide film is eliminated with respect to a semiconductor substrate in which a circuit element and an aluminum wiring are formed, or a substrate in which an oxide film such as a silicon oxide insulating film is formed on a substrate such as a semiconductor substrate in which a circuit element is formed. In the case of performing CMP for the purpose of flattening, a general polishing apparatus having a holder for supporting a substrate and a rotating plate with an abrasive cloth (pad) is used, and the abrasive slurry of the present invention is continuously pumped or the like. By a predetermined amount, and it can grind under predetermined rotation speed and pressure.

The substrate after polishing is rinsed well under running water in the same manner as in the case of normal post-treatment, and then dried after dropping water droplets adhered onto the substrate using a spin dryer or the like.

The waste liquid discharged at the time of polishing the substrate is dispersant-free, which does not use an organic dispersant at all, so that the waste liquid treatment can be performed very economically.

Embodiment of the Invention

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of this invention is described concretely based on an Example and a comparative example.

Examples 1 to 27

[Preparation of colloidal silica (20 nm)]

32 kg of methyl silicate, 100 kg of methanol, and 768 kg of pure water were prepared and mixed in a 1m <3> -tank with a cover provided with a liquid outlet, a liquid level control device, and a stirrer to prepare an A liquid. .

Further, 368 kg of methyl silicate, 100 kg of methanol, 1840 g of pure water, and 12 kg of 28 wt% ammonia water were prepared and mixed into a 3 m 3 -tank equipped with a stirrer to obtain a B liquid.

Next, the tank containing the liquid A is steam heated to distill the mixed liquid of methanol and water, and the liquid B is added so that the liquid level of the liquid A becomes constant at the time when the liquid starts to flow out of the liquid A, and the liquid B When all of the addition was completed, 240 kg of pure net was added and made to react so that the liquid level of liquid A might become constant again.

After the completion of the reaction, the reaction product was taken out and analyzed in a tank containing A liquid. As a result, a silica concentration of 20 wt% and an average particle diameter of 20 nm were colloidal silica products (colloidal silica (20 nm)).

Preparation of Colloidal Silica (70 nm)

1721.7 kg of methanol and 306.3 kg of pure water and 88.4 kg of 28 wt% ammonia water were prepared and mixed in a lidded 3 m 3 -tank equipped with a stirrer, and the liquid temperature was adjusted to 23 ± 1 ° C., and then the liquid temperature was adjusted. 404.4 kg of methyl silicate was added and reacted for 2 to 2.5 hours while maintaining at 23 ± 1 ° C.

After the completion of the reaction, the crude product of the obtained reaction mixture was transferred to a 1 m 3 -tank tank equipped with a liquid outlet, a liquid level control device, and a stirrer, and the tank was steam heated to pour out a mixture of methanol, water, and ammonia. The remaining reaction mixture is added so that the liquid level becomes constant at the time when the liquid starts to flow out of the tank, and when the addition of all of the reaction mixture is completed, pure water is added again so that the liquid level becomes constant, and the liquid temperature in the tank Pure water was added until it reached 100 degreeC.

When the liquid temperature reached 100 ° C., the heating was finished, the intermediate product was cooled down, and when the liquid temperature reached 70 ° C., an appropriate amount of 28 wt% ammonia water was added, stirred and mixed again, and then in the tank. The reaction product was taken out.

The obtained reaction product was a colloidal silica product (colloidal silica (70 nm)) having a silica concentration of 30% by weight and an average particle diameter of 70 nm.

Preparation of Colloidal Silica (170 nm)

In a 1.8 m 3 -tank tank equipped with a stirrer, 885.1 kg of methanol and 63.1 kg of pure water and 113.25 kg of 28 wt% ammonia water were prepared and mixed, and then the temperature was adjusted to 23 ± 1 ° C., and then the liquid temperature was 23 171.1 kg of methyl silicate was added thereto under stirring for 3 hours while maintaining the temperature at ± 1 ° C.

After the completion of the reaction, the crude mixture of the obtained reaction mixture was transferred to a 1 m 3 -tank tank equipped with a liquid outlet, a liquid level control device and a stirrer, and the tank was steam heated to drain a mixture of methanol, water and ammonia, and then The remaining reaction mixture is added so that the liquid level becomes constant at the time when the liquid starts to flow out, and when the addition of all the reaction mixtures is completed, pure water is added again to keep the liquid level constant, and the liquid temperature in the tank reaches 100 ° C. Pure water was added until it was.

When the liquid temperature reached 100 ° C., the heating was finished, the intermediate product was cooled down, and when the liquid temperature reached 70 ° C., an appropriate amount of 28 wt% ammonia water was added, stirred and mixed again, and then in the tank. The reaction product was taken out.

The obtained reaction product was a colloidal silica product (colloidal silica (170 nm)) having a silica concentration of 22% by weight and an average particle diameter of 170 nm.

[Preparation of Abrasive Slurry]

As the dispersion medium, three types of colloidal silica obtained above as colloidal fine particles were used, using cerium oxide particles (trade name: TE-508 manufactured by Seiko Chemical Co., Ltd.) having an average particle diameter of 1.1 mu m and a maximum particle diameter of 8 mu m. Using pure water, it mix | blended in the ratio shown in Table 1, it mixed uniformly with the stirrer, and prepared the abrasive slurry of each Example 1-27.

[Evaluation of Sedimentation, Aggregation and Redispersibility]

About the abrasive slurry of each obtained Example 1-27, 50 ml of this was put in a 100 ml test tube, and left to stand for 1 month, and the state of sedimentation and aggregation was observed visually.

Further, 50 ml of the abrasive slurry was placed in a 100 ml-polyethylene container, and left for one month to stand still. Thereafter, shaking by hand was used to visually observe the redispersibility, and was then laid horizontally on a table-type ball mill stirrer (form V-1M manufactured by a granular company) and subjected to a stirring revolution of 100 rpm and a stirring time of 10 minutes. After stirring, the redispersibility by the stirrer was visually observed.

As a result of the precipitation, aggregation state and redispersibility of the above,

(Double-circle): The whole sedimentation part is soft, it can be redispersed by hand shaking in few seconds, and can be redispersed within 5 minutes by the stirrer,

(Circle): Although there is a hard part in a precipitation part, it requires about 30 second for redispersion by shaking by hand, and about 10 minutes for redispersion by a stirrer,

(Triangle | delta): Although there is a hard part in a precipitation part, it requires 2 minutes or more for redispersion by shaking by hand, and 10 minutes or more for redispersion by a stirrer,

X: The whole precipitation part solidified completely, and even if it shakes by hand for 10 minutes, it does not redistribute and it evaluates by four steps of about 10 minutes for redispersion by a stirrer.

The results are shown in Table 1.

[Quartz Polishing Rate]

In addition, the slurry slurry was diluted three times with ultrapure water, and a rotation speed of 200 rpm, a working pressure of 500 g / cm 2, and a supply rate of the polishing slurry were prepared using a CMP polishing machine (manufactured by Nanofactor, FACT-200) equipped with an abrasive cloth. Under the conditions of ml / min, a sample (a 3.3 cm wide x 2.6 cm wide, 1.15 mm quartz substrate) was polished for 10 minutes, the thickness of the sample before and after polishing was measured by a micrometer, and the quartz thickness of the sample before and after polishing was measured. The polishing rate (μm / 10 min) for the substrate (SiO ₂ ) was obtained.

The results are shown in Table 1.

Comparative Examples 1-15

Polyvinylpyrrolidone (PVP) was used as the organic dispersant, and the abrasive slurry of Comparative Examples 1 to 15 was prepared in the same manner as in Examples 1 to 27. For each of Comparative Examples 1 to 15 abrasive obtained in the same manner as in each of Examples 1-27 and evaluating the precipitation, coagulation status, and the redispersibility, and the polishing rate (㎛ / 10min on a quartz substrate (SiO ₂₎ ) Was obtained.

The results are shown in Table 1 together with the above Examples 1 to 27.

Example No. One 2 3 4 5 6 7 8 9 Polishing Composition (wt%) Cerium oxide particles (CeO ₂ ) 5 15 30 5 15 30 5 15 30 Colloidal Silica (20 nm) One One One 2 2 2 5 5 5 Dispersant - - - - - - - - - Evaluation of Precipitation Coagulation Status and Redispersibility ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ Quartz substrate polishing rate (3-fold diluent: μm / 10 min) 10 10 10 10 10 10 10 10 10 Example No. 10 11 12 13 14 15 16 17 18 Polishing Composition (wt%) Cerium oxide particles (CeO ₂ ) 5 15 30 5 15 30 5 15 30 Colloidal Silica (70 nm) One One One 2 2 2 5 5 5 Dispersant - - - - - - - - - Evaluation of Precipitation Coagulation Status and Redispersibility ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ Quartz substrate polishing rate (3-fold diluent: μm / 10 min) 10 10 10 10 10 10 10 10 10 Example No. 19 20 21 22 23 24 25 26 27 Abrasive Composition (wt%) Cerium oxide particles (CeO ₂ ) 5 15 30 5 15 30 5 15 30 Colloidal Silica (170 nm) One One One 2 2 2 5 5 5 Dispersant - - - - - - - - - Evaluation of Precipitation Coagulation Status and Redispersibility ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ Quartz substrate polishing rate (3-fold diluent: μm / 10 min) 10 10 10 10 10 10 10 10 10 Comparative Example No. One 2 3 4 5 6 7 8 9 Abrasive Composition (wt%) Cerium oxide particles (CeO ₂ ) 5 15 30 5 15 30 5 15 30 Colloidal silica - - - - - - - - - Dispersant - - - One One One 3 3 3 Evaluation of Precipitation Coagulation Status and Redispersibility × × × △ △ △ × × × Quartz substrate polishing rate (3-fold diluent: μm / 10 min) - - - 10 10 10 10 10 10 Comparative Example No. 10 11 12 13 14 15 Abrasive Composition (wt%) Cerium oxide particles (CeO ₂ ) 5 15 30 5 15 30 Colloidal silica - - - - - - Dispersant One One One 3 3 3 Evaluation of Precipitation Coagulation Status and Redispersibility △ △ △ ○ △ △ Quartz substrate polishing rate (3-fold diluent: μm / 10 min) 10 10 10 10 10 10

As is clear from the results shown in Table 1, all of the abrasive slurries of Examples 1 to 27 of the present invention exhibited excellent performance in the evaluation of sedimentation / aggregation state and redispersibility, and in quartz substrate polishing rate. And the abrasive slurries of Comparative Examples 1 to 3, in which no dispersant was added, could not be re-dispersed and the polishing rate was not measured. It took a long time for redispersion, and it turned out that the abrasive slurry of this invention has the outstanding performance especially in sedimentation, aggregation state, and redispersibility.

ADVANTAGE OF THE INVENTION According to this invention, the abrasive slurry which is excellent in dispersion stability over a long period of time, and redispersibility is favorable, can solve the problem of sedimentation and aggregation as much as possible, and can be used in the dispersant free which uses no organic type dispersing agent at all. Can be provided.

In addition, by using the abrasive slurry of the present invention, it is possible to industrially advantageously produce substrates such as silicon substrates used in semiconductor manufacturing steps and aluminum substrates used in electrostatic chuck manufacturing steps by CMP.

Claims (8)

Abrasive fine particles composed of one or two or more oxides; Colloidal fine particles having a colloidal oxide having an average particle diameter smaller than that of the abrasive fine particles; And a dispersion medium for dispersing these abrasive fine particles and colloidal fine particles. The average particle diameter (Dp) of the abrasive fine particles is 100 to 5,000 nm, the average particle diameter (Dc) of the colloidal fine particles is 10 to 300 nm, and the average particle diameter (Dp) and the colloidal fine particles of the abrasive fine particles An abrasive slurry excellent in dispersion stability having a particle size ratio (Dc / Cp) of 10 to an average particle diameter (Dc). The abrasive grain and colloidal fine particles according to claim 1 or 2, wherein the abrasive grain fine particles have a particle concentration (Cp) of 5 to 30% by weight, and the colloidal fine particles have a particle concentration (Cc) of 0.1 to 5% by weight. An abrasive slurry excellent in dispersion stability having a weight compounding ratio (Cc / Cp) of 1 or less. The abrasive slurry excellent in dispersion stability in any one of Claims 1-3 whose dispersion medium is water or the aqueous dispersion medium which has water as a main component. The polishing slurry according to any one of claims 1 to 4, wherein the polishing fine particles are cerium oxide particles. The abrasive slurry with excellent dispersion stability according to any one of claims 1 to 5, wherein the colloidal fine particles are colloidal silica. A method for producing an inorganic substrate, comprising a polishing step of polishing the substrate using the abrasive slurry according to any one of claims 1 to 6. The method for producing a substrate according to claim 7, wherein the substrate has an oxide film on its surface.