JP2000160142A - Polishing fluid composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a polishing fluid composition capable of improving polishing speed without causing surface defect on the surface of an polishing object and capable of reducing surface roughness by including (A) a chelating compound, (B) partially esterified and/or etherified compounds of polyhydric alcohol and (C) water. SOLUTION: This polishing fluid composition includes (A) a chelating compound (preferably an aminocarboxylic acid) or its salt, (B) partially esterified and/or etherified compounds of polyhydric alcohol (preferably a sucrose ester) and (C) water. The composition preferably includes (D) abrasive (abrasive grain such as alumina grain or silicon carbide one). The contents of the ingredients A, B and C are preferably 0.05-20 wt.% and 50-99.9 wt.% respectively. When the ingredient D is included, it is blended in an amount of 0.01-40 pts.wt. based on 100 pts.wt. of the weight of the composition comprising the ingredients A, B and C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polishing composition and a polishing method.

[0002]

2. Description of the Related Art As the density of hard disks increases, the polishing rate of a hard disk substrate must be increased and the surface roughness must be reduced in the polishing step.
With higher integration and higher speed, the miniaturization of the design room of the semiconductor device has progressed, the depth of focus in the device manufacturing process has become shallower, and the flatness of the pattern formation surface has been further required, and the chelating compound or its chelating compound has been required. Polishing liquid compositions and polishing methods using salts have been studied (JP-B-7-81132).

However, the use of only a chelating compound or a salt thereof is not sufficient in the effect of reducing the surface defects such as surface flatness, scratches, pits and the like of the hard disk substrate and the semiconductor on which the pattern is formed. In some cases, surface defects were increased, which was not satisfactory as a polishing composition.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polishing composition and a polishing composition which can improve the polishing rate and reduce the surface roughness without causing surface defects on the surface of the object to be polished. An object of the present invention is to provide a method for polishing a polishing substrate.

[0005]

That is, the gist of the present invention is as follows.
[1] a polishing composition comprising a chelating compound or a salt thereof, a partially esterified and / or partially etherified product of a polyhydric alcohol compound, and water (hereinafter, referred to as a first polishing composition); [2] The polishing composition according to the above [1] (hereinafter, referred to as a second polishing composition) further containing an abrasive, [3] The polishing composition according to the above [1] or [2]. The present invention relates to a method for polishing a substrate to be polished in which the substrate is polished by using an object.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The chelating compound used in the present invention is a compound having a polydentate ligand capable of forming a complex by binding to a metal ion. For example, hydroxycarboxylic acids such as tartaric acid and malic acid; aminocarboxylic acids such as nitrotriacetic acid, ethylenediaminetetraacetic acid and diethylenetriaminepentaacetic acid; polymer compounds into which these aminocarboxylic acids are introduced; (meth) acrylic acid polymers; And copolymers of (meth) acrylic acid and other monomers. Among the chelating compounds, those having two or more carboxyl groups are preferable from the viewpoint of improving the polishing rate, aminocarboxylic acids having an amino group are more preferable, and polyaminocarboxylic acids having two or more amino groups are particularly preferable. preferable.

The salts of these chelating compounds are not particularly limited as long as they are salts of substances capable of forming salts with the chelating compounds. Specific examples include salts with metals, ammonium, alkylammoniums, organic amines, and the like.
Specific examples of metals include Periodic Table (Long Period Type) 1A, 1B,
Metals belonging to groups 2A, 2B, 3A, 3B, 4A, 6A, 7A and 8 are mentioned. Among these metals, from the viewpoint of improving the polishing rate, groups 1A, 3A, 3B, 7A and 8 are preferable, and 1A,
Groups 3A, 3B, 7A and 8 are more preferred, cerium belonging to group 3A, aluminum belonging to group 3B, manganese belonging to group 7A and iron and cobalt belonging to group 8 are most preferred, and aluminum belonging to group 3B is most preferred. In addition, about the salt of these chelating compounds, a salt may be formed with a metal which is required in advance, or an inorganic acid salt such as a nitrate, a sulfate or a phosphate containing these metals, an acetate or the like. The desired salt may be obtained by mixing an organic acid salt and a chelating compound and performing chelate exchange in the polishing composition.

Specific examples of the alkyl ammonium include
Examples include dimethyl ammonium, trimethyl ammonium, tetramethyl ammonium, tetraethyl ammonium, tetrabutyl ammonium and the like. Specific examples of the organic amine include alkanolamine.

The salt of the chelating compound may be a salt of the chelating compound with two or more substances capable of forming a salt. Particularly, a salt of aluminum with another substance is preferable.

These chelating compounds or salts thereof may be used alone or in combination of two or more.

The content of the chelating compound or its salt in the first polishing composition is preferably from 0.05 to 20% by weight, more preferably from 0.1 to 20% by weight, from the viewpoint of improving the polishing rate.
-15% by weight, more preferably 0.5-10% by weight.

The polyhydric alcohol compound includes a cyclic polyhydric alcohol compound and a chain polyhydric alcohol compound. Examples of the cyclic polyhydric alcohol include a polyhydric alcohol having a pyranose skeleton and / or a furanose skeleton, a polyhydric alcohol compound having a functional group other than a hydroxyl group in the cyclic polyhydric alcohol, and an alkylene oxide adduct thereof. Specific examples thereof include D-ribose, D-arabinose, D-xylose, D-lyxose, D-allose, D-altrose, D-glucose, D-mannose, D-
Growth, D-idose, D-galactose, D-talose,
D-fructose, D-erythrose, D-threose,
Trehalose, maltose, cellobiose, gentiobiose, lactose, raffinose, gentianose,
Meletitol, maltotriose, cellotriose, manninotriose, starch, cellulose, mannan, sucrose (sucrose), stachyose, inulin, D-glucuronic acid, D-galacturonic acid, D-mannuronic acid, L-iduronic acid, L -Guluronic acid, D-glucosamine, D-galactosamine, pectic acid, alginic acid, chitosan and the like.

Examples of the linear polyhydric alcohol compound include a linear polyhydric alcohol, a linear polyhydric alcohol compound having a functional group other than a hydroxyl group in the linear polyhydric alcohol, and an alkylene oxide adduct thereof. Specific examples thereof include glycerin, erythritol, ribitol, p-arabinitol, xylitol, allitol, sorbitol, mannitol, p-iditol, galactitol, D-
Talitol, trimethylolpropane, trimethylolethane, 1,2,4-butanetriol, 1,2,6-hexanetriol, 1,1,1-hexanetriol, ditrimethylolpropane, pentaerythritol, dipentaerythritol, polyvinyl alcohol , Diglycerin, polyglycerin, gluconic acid and the like, and alkylene oxide adducts thereof.

[0014] The molecular weight of the polyhydric alcohol compound is preferably 100 from the viewpoint of improving the solubility in water and the discharging property of the abrasive powder.
It is from 10,000 to 10,000, preferably from 200 to 8,000, and more preferably from 300 to 5,000. Some polyhydric alcohol compounds have a molecular weight of about several hundred thousand, but from the viewpoint of water solubility and viscosity, these are subjected to a treatment such as hydrolysis to obtain a polyhydric alcohol compound having a target molecular weight. After that, a derivative may be used.

The alkylene oxide of the alkylene oxide adduct of the polyhydric alcohol compound preferably has 2 to 4 carbon atoms from the viewpoint of improving the water solubility of the polyhydric alcohol compound. Suitable alkylene oxides include
Ethylene oxide, propylene oxide, butylene oxide and the like can be mentioned, and these can be used alone or in combination. Of these, ethylene oxide is particularly preferred. When two or more alkylene oxides are used, the alkylene oxides may be randomly added or block-added. The number of moles of the alkylene oxide added to the polyhydric alcohol compound is determined in consideration of the solubility of the added compound in water and the increase in viscosity. The number of moles of the alkylene oxide added is preferably 50 mol or less per hydroxyl group of the polyhydric alcohol compound,
30 mol or less is more preferable.

A partially esterified and / or partially etherified product of a polyhydric alcohol compound (hereinafter referred to as a derivative of the polyhydric alcohol compound) can be obtained by a usual esterification reaction or etherification reaction. For example, a partially esterified product is obtained by reacting a hydroxyl group of a polyhydric alcohol compound with a carboxylic acid, and a polyhydric alcohol compound having a carboxyl group may be esterified at a carboxyl moiety using an alcoholate or the like. The partially etherified product can be obtained by changing the hydroxyl group of a polyhydric alcohol compound to an alkoxide with an alkali metal or the like and reacting the alkoxide with an alkyl halide or the like.

The carbon number of the partially esterified or partially etherified acyl group or hydrocarbon group is determined from the viewpoints of solubility in water, viscosity increase upon dissolution, and reduction of the surface roughness of the polished surface. It is preferably 1 to 24, more preferably 2 to 22, still more preferably 3 to 20, and most preferably 4 to 20. These acyl groups or hydrocarbon groups may be aliphatic or aromatic. Further, one molecule may have two or more acyl groups, two or more hydrocarbon groups, or one or more acyl groups and one or more hydrocarbon groups simultaneously. good. Aliphatic is particularly preferred from the viewpoint of reducing the surface roughness of the polished surface. In addition, in the aliphatic, any of saturated and unsaturated groups may be used,
Any of a straight-chain or branched group may be used.

The derivatives of the polyhydric alcohol compounds may be used alone or in combination of two or more.

The esterification rate or etherification rate of the derivative of the polyhydric alcohol compound is from 3 to 95%, preferably from 5 to 70%, from the viewpoint of improving the solubility in water and reducing the surface roughness and surface defects. More preferably, 10 to 50% is desirably esterified or etherified. The esterification rate or etherification rate is the average ratio of esterification or etherification to the total number of all hydroxyl groups and all carboxyl groups of the polyhydric alcohol compound (the distribution of the average ratio of esterification or etherification by the compound, respectively). Average in some cases).

Among the derivatives of the polyhydric alcohol compounds,
From the viewpoint of reducing the surface roughness, a derivative of a cyclic polyhydric alcohol compound is preferred, and a partially esterified product of sucrose is particularly preferred.

The synergistic effect of the combination of a chelating compound or a salt thereof and a derivative of a polyhydric alcohol compound is that the chelating compound acts on abrasives, polishing powders, substrates to be polished, etc. to improve dispersibility. It is presumed that the polishing rate is improved by the action of improving the drainage of the polishing liquid. However, a chelating compound or a salt thereof alone is insufficient to suppress surface defects considered to be mainly caused by a coarse abrasive contained in a fixed grinding wheel or a second polishing composition, and water It is considered that since the polishing composition is used as a medium, the frictional resistance between the fixed grindstone or the abrasive and the substrate to be polished increases, and the surface roughness of the substrate to be polished cannot be improved by the generated frictional heat or the like. On the other hand, when a derivative of a polyhydric alcohol compound is combined with a chelating compound or a salt thereof, a functional group part such as a hydroxyl group in the derivative of the polyhydric alcohol compound is adsorbed on the surface of the substrate to be polished, and is partially esterified or partially esterified. The etherified acyl group or hydrocarbon group portion reduces the impact on the substrate to be polished such as a coarse abrasive, and the derivative of the polyhydric alcohol compound reduces the frictional resistance during polishing, thereby the chelating compound It is considered that the function is exhibited, the generation of surface defects is suppressed while the polishing rate is improved, and the polishing can be performed at a high speed while the surface roughness is lower than before.

The content of the polyhydric alcohol compound derivative in the first polishing composition is preferably from 0.01 to 20% by weight, more preferably from 0.03 to 20% by weight, from the viewpoint of reducing the surface roughness and surface defects of the polished surface. It is 15% by weight, more preferably 0.05 to 10% by weight.

Further, from the viewpoint of improving the polishing rate and sufficiently exhibiting the effect of reducing surface roughness and surface defects,
The content ratio of the chelating compound or the salt thereof and the derivative of the polyhydric alcohol compound [the content of the chelating compound or the salt thereof (% by weight) / the content of the derivative of the polyhydric alcohol compound (% by weight)] is 0.002 to 0.002. 2000, preferably 0.01-300
, More preferably 0.05 to 50. Especially in the polishing of substrates for precision parts such as substrates made of Ni-P plated aluminum alloy, 0.01 to
100, preferably from 0.03 to 50, more preferably from 0.05 to 30, when the occurrence of surface defects is suppressed while improving the polishing rate, it is possible to polish at a high speed while lowering the surface roughness than before, especially preferable.

The water in the polishing composition of the present invention is used as a medium, and its content is preferably from 50 to 99.9 from the viewpoint that the object to be polished can be efficiently polished. %, More preferably 70 to 99.5% by weight, even more preferably 90 to 99% by weight.

The first polishing composition of the present invention having such a composition is effective in a polishing system using a fixed grindstone or the like. For example, by using the first polishing composition of the present invention during polishing by a polishing method using a fixed grindstone, the polishing target can be improved in polishing rate and surface roughness without causing surface defects such as scratches and pits on the substrate to be polished. Can be reduced.

The second polishing composition of the present invention is obtained by further adding an abrasive to the first polishing composition.

As the abrasive used in the second polishing composition of the present invention, abrasive grains generally used for polishing can be used. Examples of the abrasive include metal, metal or metalloid carbide, metal or metalloid nitride, metal or metalloid oxide, metal or metalloid boride, diamond and the like. In addition, metal or metalloid element is 2A, 2B, 3A, 3B, 4A, 4B, 5A, 6A, 7A of the periodic table (long period type).
Or, it is derived from group 8. Specific examples of the abrasive include alumina particles, silicon carbide particles, diamond particles, magnesium oxide particles, zinc oxide particles, cerium oxide particles, zirconium oxide particles, colloidal silica particles, fumed silica particles, and the like. Use of the above is preferable from the viewpoint of improving the polishing rate. In particular, alumina particles, cerium oxide particles, zirconium oxide particles, colloidal silica particles, and fumed silica particles are suitable for polishing substrates for precision parts such as semiconductor wafers, semiconductor elements, and substrates for magnetic recording media. The colloidal silica particles are suitable for polishing a substrate for a magnetic recording medium. Among the alumina particles, the intermediate alumina particles are preferable because the surface roughness of the object to be polished can be extremely low. The term “intermediate alumina particles” as used herein is a general term for alumina particles other than α-alumina particles, and specifically, γ-alumina particles, δ-alumina particles, θ-alumina particles, and η-alumina particles. And amorphous alumina particles. As the alumina particles, alumina-based particles in which secondary particles are redispersed into primary particles when mechanically stirring or polishing the polishing composition of the present invention can be suitably used.

The average particle size of the primary particles of the abrasive is preferably from 0.002 to 3 μm, more preferably from 0.01 to 1 μm, and still more preferably from 0.02 to 0.
It is 8 μm, particularly preferably 0.05 to 0.5 μm. In particular, when alumina-based particles are used as the abrasive, from the viewpoint of reducing the surface roughness of the object to be polished, preferably 0.01 to 1
μm, more preferably 0.02 to 0.8 μm, particularly preferably 0.05 to 0.5 μm. Furthermore, when the primary particles are aggregated to form secondary particles, similarly from the viewpoint of improving the polishing rate and reducing the surface roughness of the object to be polished, the average particle size of the secondary particles is , Preferably 0.05-2 μ
m, more preferably 0.1 to 1.5 μm, particularly preferably
It is 0.3 to 1.2 μm. The average particle size of the primary particles of the abrasive is observed with a scanning electron microscope (preferably 3000 to 10,000).
) And image analysis, and measuring the biaxial average diameter. Further, the average particle size of the secondary particles can be measured as a volume average particle size using a laser light diffraction method.

The Knoop hardness (JIS Z-2251) of the abrasive is preferably from 700 to 9000, and from 1000 to 5,000, from the viewpoint of obtaining a sufficient polishing rate and not generating surface defects on the object to be polished. More preferably, it is even more preferably 1500 to 3000.

The specific gravity of the abrasive is preferably from 2 to 6, more preferably from 2 to 4, from the viewpoints of dispersibility, supply to a polishing apparatus, and recovery and reuse.

In the second polishing composition of the present invention, the synergistic effect of improving the polishing rate and preventing the generation of surface defects by adding an abrasive, a chelating compound or a salt thereof and a derivative of a polyhydric alcohol compound is obtained. From the viewpoint of improvement, particularly preferably used abrasive, the Knoop hardness is 1500 to 300
0, α-alumina particles or γ having a purity of 98% by weight or more, preferably 99% by weight or more, particularly preferably 99.9% by weight or more.
-Alumina particles. These abrasives can be manufactured by a crystal growth method (such as Bernoulli method) using a high-purity aluminum salt. In addition, the purity of this abrasive is
It can be measured by dissolving 1 to 3 g of an abrasive in an aqueous acid or alkali solution, and quantifying aluminum ions using a plasma emission spectrometry.

The abrasive is used in a slurry state using water as a medium. It is preferable that the content of the abrasive in the second polishing composition of the present invention is appropriately determined according to the viscosity of the polishing composition, the required quality of the object to be polished, and the like. The content of the abrasive in the second polishing composition of the present invention is preferably 100% by weight of the first polishing composition from the viewpoints of economy and reduction in surface roughness to enable efficient polishing. 0.01 to 40 parts by weight, preferably 0.1 to 25 parts by weight,
More preferably, the amount is 1 to 15 parts by weight.

Further, from the viewpoint of improving the polishing rate and sufficiently exhibiting the effect of reducing the surface roughness, the abrasive in the second polishing composition of the present invention, a chelating compound or a salt thereof, and a polyhydric alcohol. The content ratio of the compound to the derivative [content of the abrasive (% by weight) / content of the chelating compound or its salt and the derivative of the polyhydric alcohol compound (% by weight)] is 0.001 to 200, preferably 0.01 to 200. It is desirable that the amount be 100, more preferably 0.1 to 50, particularly preferably 1 to 25.

The first and second abrasive compositions of the present invention can contain other components as necessary. Examples of the other components include metal salts and ammonium salts of monomer type acid compounds, peroxides, thickeners, dispersants, rust inhibitors, basic substances, surfactants and the like. Specific examples of the metal salt / ammonium salt of a monomeric acid compound, a peroxide, a thickener, and a dispersant are described in JP-A-62-25187, page 2, upper right, line 3 to upper right, 11 Line 2, p. 2 of JP-A-63-251163, upper left view 6
Line 3 to line 8 on the upper left, page 2 of JP-A No. 1-205973, line 5 on the left, page 3 to line 2 on the upper right, and JP-A 4-275387, line 27 on the left of page 2 Line 12 on the left side of the page, line 23 on the right side of page 2 of JP-A-5-59351, line 37 on the left side of page 3, line 15 on the lower left column of page 2 on the page 2 of JP-A-2-58683, line 10 on the lower right side Eye, JP-A 7-216345
No. 4, page 3 on the left and line 25 on the left.

The content of these components in the polishing composition of the present invention is not particularly limited.
It is preferably about 10% by weight.

The pH of the first and second polishing compositions of the present invention
It is preferable to appropriately determine the value according to the type of the object to be polished, the required quality, and the like. For example, the pH of the first and second polishing compositions of the present invention is more preferably from 2 to 12, from the viewpoints of cleaning the substrate to be polished and preventing corrosion of the processing machine. Further, in the case of a precision component substrate whose main object is a metal such as an aluminum substrate in which the object to be polished is Ni-P plated, from 2 to 8 are particularly preferable from the viewpoint of improving the polishing rate and improving the surface quality.
Further, when used for polishing semiconductor wafers and semiconductor elements, particularly for polishing silicon wafers, from the viewpoint of improving the polishing rate and improving the surface quality, 7 to 12 is preferable, 8 to 12 is more preferable, and 9 to 11 is preferable. Is particularly preferred. The pH is, if necessary, an inorganic acid such as nitric acid or sulfuric acid, a metal salt of the monomer type acid compound, an ammonium salt, a peroxide, potassium hydroxide, sodium hydroxide, ammonia, an alkyl ammonium, an amine, or the like. It can be adjusted by appropriately mixing a basic substance in a desired amount.

The method of polishing a substrate to be polished according to the present invention comprises the step of polishing a substrate to be polished using the first and second polishing liquid compositions of the present invention. In particular, the second polishing liquid composition of the present invention By using, a substrate for precision parts can be suitably manufactured.

Further, the method of manufacturing a substrate to be polished according to the present invention comprises:
A step of polishing a substrate to be polished using the first and second polishing liquid compositions of the present invention.

The material to be polished represented by the substrate to be polished is, for example, a metal or semimetal such as silicon, aluminum, nickel, tungsten or copper, an alloy containing these metals as a main component, glass, glassy carbon, or the like. And glassy substances such as amorphous carbon, ceramic materials such as alumina, titanium carbide and silicon dioxide, and resins such as polyimide resins. Among these, metals such as aluminum, nickel, tungsten, and copper, alloys containing these metals as main components, and semiconductor substrates such as semiconductor elements containing these metals are preferable. In particular, when the polishing composition of the present invention is used when polishing a substrate to be polished made of a Ni-P-plated aluminum alloy, the occurrence of surface defects such as scratches and pits is suppressed, and the surface roughness is reduced. This is preferable because it can be polished at a high speed while reducing the level of the technology.

The shape of the object to be polished is not particularly limited. For example, a shape having a flat surface such as a disk, a plate, a slab, or a prism, or a shape having a curved surface such as a lens is used. It is an object of polishing using the polishing composition of the present invention. Among them, it is particularly excellent in polishing a disk-shaped object to be polished.

The first polishing composition of the present invention is suitably used particularly for high-precision polishing of a precision component, such as a flat surface, a surface, and an inner surface of a cylinder. For example, it is suitable for polishing that requires a high-precision plane or surface such as an optical lens, an optical mirror, a half mirror, and an optical prism.

The second polishing composition of the present invention is suitably used particularly for polishing precision component substrates. For example, it is suitable for polishing substrates of magnetic recording media such as hard disks, optical disks, and magneto-optical disks, semiconductor wafers, semiconductor substrates such as semiconductor elements, optical lenses, optical mirrors, half mirrors, optical prisms, and the like. Among these, it is suitable for polishing a substrate of a magnetic recording medium or a semiconductor substrate, particularly a hard disk substrate. The polishing of the semiconductor element includes, for example, polishing performed in a step of flattening an interlayer insulating film, a step of forming a buried metal wiring, a step of forming a buried element isolation film, and a step of forming a buried capacitor.

By polishing the substrate to be polished as described above, a precision component substrate or the like can be manufactured.

The polishing composition of the present invention is particularly effective in the polishing step, but can be similarly applied to other polishing steps, for example, a lapping step.

[0045]

Examples 1 to 23 and Comparative Examples 1 to 10 A chelating compound or a salt thereof shown in Table 1, a derivative of a polyhydric alcohol compound shown in Table 2, and ion-exchanged water were mixed and stirred. First polishing liquid compositions having the compositions shown in Tables 3 and 4 were obtained.

[0046]

[Table 1]

[0047]

[Table 2]

10 parts by weight of α-alumina (purity: about 99.9%) having a Knoop hardness of 2,000, a primary average particle diameter of 0.29 μm, and a secondary average particle diameter of 0.75 μm are added to 100 parts by weight of the first polishing composition. Mixing and stirring gave a second polishing composition. Using the obtained second polishing composition, the center line average roughness Ra measured by the following method was 0.1 μm, the thickness was 0.9 mm, and the diameter was 2.
The surface of a 5-inch Ni-P plated aluminum alloy substrate is polished by a double-sided processing machine under the following double-sided processing machine settings, and used as a substrate for magnetic recording media
A polished aluminum alloy substrate plated with Ni-P was obtained.

The setting conditions of the double-side processing machine are shown below. Double-sided processing machine used: Kyoritsu Seiki Co., Ltd., 6B type double-sided processing machine Processing pressure: 9.8 kPa Polishing pad: Polytex DG (Rodel Nitta) Surface plate rotation speed: 40 r / min Polishing composition supply flow rate: 30 mL / min Polishing time: 7min

The thickness of the aluminum alloy substrate after polishing was measured, and the rate of decrease in thickness was determined from the change in the thickness of the aluminum alloy substrate before and after polishing, and a relative value (relative speed) was determined based on Comparative Example 1. Was.

The center line roughness of the surface of each substrate after polishing
Ra and surface defects (scratch) were measured according to the following methods. The center line roughness Ra was determined as a relative value (relative roughness) with reference to Comparative Example 1. Table 3 shows the results.

[Center Line Average Roughness Ra (Relative Roughness)] Measured under the following conditions using a tally step manufactured by Rank Taylor Hobson. Stylus tip size: 25 μm × 25 μm High pass filter: 80 μm Measurement length: 0.64 mm

[Surface Defects (Scratch)] Using an optical microscope observation (differential interference microscope), the surface of each substrate was measured at six points at 60 ° intervals at a magnification of × 50. The scratch depth was measured with Zygo (manufactured by Zygo). The evaluation criteria are as follows.

-Evaluation Criteria- S: 0 scratches exceeding 50 nm in depth / 1 visual field A: Scratch exceeding 50 nm in depth is less than 0.5 on average / 1
Field of view B: 0.5 or more and less than 1 scratch on average over 50 nm depth / 1 field of view C: 1 or more scratch on average over 50 nm depth / 1 field of view

[0055]

[Table 3]

[0056]

[Table 4]

From the results shown in Tables 3 and 4, from Examples 1 to
When the second polishing composition obtained in 23 was used, in comparison with the case where the polishing compositions obtained in Comparative Examples 1 to 10 were used,
It can be seen that a substrate to be polished having a high polishing rate, a small surface roughness, few scratches and a good polished surface can be obtained. Further, in the second polishing composition,
When only the chelating compound or a salt thereof shown in Comparative Examples 2 to 4 is used, the polishing rate (relative rate) is improved, but the effect of improving the surface roughness (relative roughness) and the surface defect is not sufficient. When only the derivatives of the polyhydric alcohol compounds shown in Comparative Examples 5 to 8 were used, the surface roughness (relative roughness)
Although there is an effect of improving surface defects, the polishing speed (relative speed) is not improved. When these chelating compounds or salts thereof and derivatives of polyhydric alcohol compounds are used in combination, both polishing rate (relative speed), surface roughness (relative roughness), and surface defect performance as shown in Examples 1 to 23 Can be improved.

[0058]

According to the present invention, it is possible to obtain a polishing composition capable of improving the polishing rate and reducing the surface roughness without causing surface defects on the surface of the object to be polished.
The use of the polishing composition of the present invention also has the effect of improving the polishing rate and reducing the surface roughness without causing defects such as scratches and pits on the surface of the object to be polished. Is done.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yoshiaki Oshima 1334 Minato, Wakayama-shi Kao Research Institute F-term (reference) 3C058 AA06 AA07 AC04 CA05 CA06 CB01 CB03 DA02

Claims (5)

[Claims] 1. A polishing composition comprising a chelating compound or a salt thereof, a partially esterified and / or partially etherified product of a polyhydric alcohol compound, and water. 2. The polishing composition according to claim 1, wherein the chelating compound is an aminocarboxylic acid. 3. The polishing composition according to claim 1, wherein the partially esterified and / or partially etherified product of the polyhydric alcohol compound is a sucrose ester. 4. The method according to claim 1, further comprising an abrasive.
3. The polishing composition according to any one of 3. 5. A method for polishing a substrate to be polished, comprising polishing the substrate to be polished using the polishing composition according to claim 1.