KR20180118603A - Abrasive composition - Google Patents

Abstract

An object of the present invention is to provide a polishing composition which is excellent in wafer protecting ability (alkali-etch resistance) and can be expected to lower the haze value while maintaining a low particle level. The present invention relates to a process for producing a water-soluble polymer, which comprises (A) an abrasive grain, (B) a water-soluble alkaline compound, (C) at least one organic compound selected from hydroxyethyl cellulose having a weight average molecular weight of 500,000 or less, (D) an alkyl glucoside and an alkanolamide, (E) water, and a polishing method of a silicon wafer using the composition.

Description

Abrasive composition

The present invention relates to a polishing composition suitable for polishing a silicon wafer for the production of a semiconductor substrate. More particularly, the present invention relates to a polishing composition suitable for final polishing of bare silicon wafers for the production of semiconductor substrates.

The bare silicon wafers for the production of semiconductor substrates are required to have a low number of particles remaining on the surface and a low haze value. However, since the design rule of the semiconductor substrate tends to be finer, the demand for these surface quality has become more severe.

Therefore, proposals for improving the surface quality of silicon wafers have been made. For example, in order to reduce residues on the surface of a silicon wafer, a proposal has been made to use a hydrolyzate as the hydroxyethyl cellulose contained in the polishing composition (Patent Document 1), and in order to reduce fine particles on the surface of a silicon wafer, It has been proposed to use hydroxyethyl cellulose having a molecular weight (Patent Document 2).

A polishing composition containing silica particles, a water-soluble alkali compound, an alkylpolyglycoside and a cationized polyvinyl alcohol has been proposed as an abrasive liquid composition capable of obtaining a silicon wafer having a small number of particles and a small haze value 3).

However, in the conventional polishing composition, it has been difficult to satisfy the surface quality required for reducing the haze of the surface of the silicon wafer and the number of fine particles which are getting worse.

Japanese Patent Laid-Open No. 11-61089 Japanese Patent Application Laid-Open No. 2014-151424 Japanese Patent Application Laid-Open No. 2013-105954 Japanese Patent Application Laid-Open No. 2013-222863 Japanese Patent Application Laid-Open No. 2005-175432 Japanese Patent Application Laid-Open No. 2010-129941 Japanese Patent Application Laid-Open No. 2009-212378 Japanese Patent Application Laid-Open No. 2014-529673

An object of the present invention is to provide a polishing composition which is excellent in wafer protecting ability (alkali-etch resistance) and which can be expected to lower the haze value while maintaining a low particle level.

The particles are foreign matters such as abrasive particles adhering to the surface of the wafer, polishing pad debris, chips of silicon and the like, and haze is cloudiness observed when the light flux is irradiated on fine irregularities which are difficult to measure in the surface roughness meter of the wafer surface. The smaller the haze value, the higher the surface smoothness.

And the roughness of the surface of the silicon wafer due to the etching ability of the composition itself as a factor that the polishing composition deteriorates the quality of the surface of the silicon wafer. An object of the present invention is to provide a polishing composition which is excellent in the ability to protect silicon wafers (alkali-etch resistance) and enables a good haze value to be lowered.

Further, since it is necessary to prevent adhesion of fine silicon or abrasive grains due to drying after polishing, it is preferable that the surface of the silicon wafer immediately after polishing has appropriate hydrophilicity. The present invention provides a polishing composition capable of imparting appropriate hydrophilicity to the surface of a silicon wafer immediately after polishing.

According to the present invention,

(A) abrasive grain,

(B) a water-soluble alkali compound,

(C) a hydroxyethylcellulose having a weight average molecular weight of 500,000 or less

(D) at least one organic compound selected from alkyl glucosides and alkanolamides,

And

(E) Water

By weight.

The above-mentioned abrasive composition wherein the abrasive grains are colloidal silica is a preferred embodiment of the present invention.

The above-mentioned polishing composition wherein the colloidal silica has an average primary particle diameter of 5 to 100 nm as determined by a nitrogen adsorption method (BET method) is a preferred embodiment of the present invention.

The above-mentioned polishing composition wherein the colloidal silica is a cocoon-shaped colloidal silica obtained by reacting a condensate of an alkoxysilane with water in the presence of an ammonia or ammonium salt catalyst is a preferred embodiment of the present invention.

(B) a water-soluble alkaline compound in an amount of 0.001 to 0.05 mass%, (C) a hydroxyethyl cellulose in an amount of 0.005 to 0.05 mass%, (D) an organic compound component (D) in an amount of 0.05 to 1.0 mass% 0.0001 to 0.02% by mass is the preferred embodiment of the present invention.

The above-described polishing composition used for polishing a silicon wafer is a preferred embodiment of the present invention.

The present invention also provides a polishing method of a silicon wafer including a step of polishing the silicon wafer using the polishing composition.

According to the present invention, there is provided a polishing composition which is excellent in wafer protecting ability (alkali-etch resistance), and as a result, can be expected to have a good haze value reduction.

Further, the present invention provides a polishing composition capable of imparting appropriate hydrophilicity to the surface of a silicon wafer immediately after polishing, so that it is possible to prevent drying and fixing of polishing debris generated during abrasive grains and polishing, And as a result, a satisfactory surface quality can be expected to be realized.

According to the present invention, there is provided a polishing composition excellent in wafer protecting ability (alkali-etch resistance) and capable of imparting appropriate wettability to a wafer after polishing.

It is also known to add a surfactant to a polishing composition (for example, Patent Documents 1 to 8). In addition, alkanolamides and alkyl glucosides are all compounds known as nonionic surfactants.

However, since the polishing composition using the specific components (A) to (E) of the present invention has low etchability to the silicon wafer, the wafer protecting ability is high, and a good polishing rate is attained by addition, And the hydrophilic property of the surface of the wafer after polishing is also good.

According to the present invention,

(A) abrasive grain,

(B) a water-soluble alkali compound,

(C) a hydroxyethylcellulose having a weight average molecular weight of 500,000 or less

(D) at least one organic compound selected from alkyl glucosides and alkanolamides

And

(E) Water

And a polishing composition.

<Erection>

The abrasive grains contained in the abrasive composition of the present invention are not particularly limited as far as the abrasive grains are commonly used for polishing, and examples thereof include inorganic particles, organic particles and organic-inorganic composite particles. Among them, inorganic particles are preferable.

Examples of the inorganic particles that can be used as the abrasive grains include particles containing silicon dioxide, aluminum oxide, cerium oxide, zirconium oxide, titanium oxide, silicon nitride, manganese dioxide, silicon carbide, zinc oxide, diamond and magnesium oxide .

Specific examples of the inorganic particles of the abrasive material include silicon dioxide such as colloidal silica, fumed silica and surface-modified silica; aluminum oxide such as? -alumina,? -alumina,? -alumina,? -alumina,? -alumina, amorphous alumina, fumed alumina and colloidal alumina; Trivalent or tetravalent oxide cerium oxide, cerium oxide of hexagonal system, equiaxed or face-centered cubic system, and other cerium oxide; Zirconium oxide, zirconium oxide, zirconium oxide or other zirconium oxide; Titanium monoxide, and titanium trioxide are titanium, titanium dioxide, fumed titania, and other titanium oxide; ? -silicon nitride,? -silicon nitride, amorphous silicon nitride, and other silicon nitride; ? -dioxide,? -dioxide,?-manganese dioxide,?-manganese dioxide,?-manganese dioxide,? -manganese dioxide,? -manganese dioxide, and other manganese dioxide. These abrasives may be used alone or in combination of two or more.

Among these abrasive materials, a silicon dioxide-based material is preferable, and a colloidal silica is more preferable.

From the viewpoint of operability, it is preferable that the abrasive is a slurry.

When the abrasive grains contained in the abrasive composition of the present invention are colloidal silica, the average primary particle diameter of the silica particles determined by the nitrogen adsorption method (BET method) is 5 to 100 nm, preferably 10 to 40 nm, Is 10 to 25 nm.

The secondary particle diameter distribution of the silica particles can be measured by a dynamic light scattering method, and the cumulative 50% particle diameter D50 of the distribution (volume representation) is referred to as an average secondary particle diameter. Further, a half of the difference between the cumulative 84% particle diameter and the cumulative 16% particle diameter in the particle size distribution (volume display) is referred to as SD and the ratio of SD to D50 (SD / D50) Called coefficient CV.

The average secondary particle diameter of the silica particles is preferably 10 to 90 nm, preferably 20 to 80 nm, more preferably 25 to 70 nm, and still more preferably 25 to 40 nm.

The coefficient of variation CV of the secondary particle diameter of the silica particles is 0.10 to 0.50, preferably 0.20 to 0.40.

Particularly preferred silica particles have an average secondary particle diameter D50 of 25 to 40 nm and a coefficient of variation CV of 0.20 to 0.40.

The shape (outer shape) of the abrasive grains may be spherical or non-spherical. Specific examples of the non-spherical abrasive grains include a pinnate shape (i.e., a shape of a peanut of a peanut), a cocoon shape, a star candy shape, and a rugby ball shape. For example, it is possible to preferably employ an abrasive having a shape of a pinnate or a cocoon shape in the majority of the abrasive grains. Above all, abrasive grains having a cocoon shape are preferable.

The method of synthesizing the abrasive grains is not limited. Examples of the method for synthesizing silica particles include a hydrothermal synthesis method from water glass, a sol-gel method from alkoxysilane or a condensate thereof, and a vapor phase synthesis method from silicon chloride. From the viewpoint of reducing metal impurities, silica particles prepared by a sol-gel method from alkoxysilane or a condensate thereof are preferable.

Particularly, cocoon-like silica particles prepared by a method including a step of reacting a condensate of an alkoxysilane with water (sol-gel reaction step) (sometimes referred to as a "new cocoon-type silica particle" ) (Japanese Patent No. 4712556) is preferable from the viewpoint of improving both the polishing rate, the surface accuracy and the filtration property. The average degree of condensation of the condensate in this case is preferably from 2 to 10, more preferably from 2 to 8. Further, in this specification, unless otherwise specified, such as "cocoon type (not including toothed tooth type)", the cocoon type shall also include a toothed tooth type.

<Water-Soluble Alkali Compound>

Examples of the water-soluble alkali compound include hydroxides, carbonates and hydrogen carbonate salts of a nitrogen-containing basic compound, an alkali metal and an alkaline earth metal from the viewpoint of preventing aggregation of abrasive grains and giving an appropriate polishing rate by a chemical polishing action . Examples of the nitrogen-containing basic compound include ammonia (ammonium hydroxide), ammonium carbonate, ammonium hydrogencarbonate, organic amines, piperazines, and quaternary ammonium hydroxides. Examples of the hydroxides, carbonates and hydrogencarbonates of alkali metals and alkaline earth metals include potassium hydroxide, sodium hydroxide, potassium carbonate, potassium hydrogencarbonate, sodium carbonate and sodium hydrogencarbonate. These basic compounds may be used alone or in combination of two or more.

Among the water-soluble alkali compounds, quaternary ammonium hydroxides such as ammonia, organic amines and tetramethylammonium hydroxide are preferable from the viewpoint that they do not contain alkali metal ions. From the viewpoint of improving the surface precision of the polished surface, ammonia is particularly preferable.

(Hydroxyethylcellulose)

The weight average molecular weight (Mw) of the hydroxyethyl cellulose of the present invention (hereinafter may be abbreviated as HEC) is preferably not more than 500,000, preferably not more than 200,000, more preferably not less than 10,000 but not more than 200,000. If the weight average molecular weight of the HEC is large, the cleaning property tends to deteriorate and cause particles. Hence, the weight average molecular weight of HEC is preferably not more than 500,000, preferably not more than 200,000, more preferably not more than 200,000. Conversely, if the weight average molecular weight of the HEC is small, the ability to impart wettability to the wafer tends to decrease. Hence, the weight average molecular weight of HEC is preferably 10,000 or more. Within the above range, sufficient hydrophilicity is imparted to the wafer, good cleansing properties are exhibited, and a reduction effect of the particles is expected.

(Alkanolamide)

The alkanolamide is a compound in which an alkanolamine and a fatty acid are amide-bonded, and the alkyl chain length of the fatty acid is preferably from 6 to 22, more preferably from 6 to 18, and even more preferably from 8 to 14, . Examples of fatty acids include caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid and the like. Examples of the alkanolamine include diethanolamine, isopropanolamine, monoethanolamine, 2-aminoethyl-ethanolamine and the like. Preferred examples of the alkanolamide include caprylic acid diethanolamide, pelargonic acid diethanolamide, capric acid diethanolamide, lauric acid diethanolamide, myristic acid diethanolamide, palmitic acid diethanolamide, stearic acid diethanolamide , Oleic acid diethanolamide diethanolamide, and lauric acid monoethanolamide. Or a mixture thereof.

(Alkyl glucoside)

The alkyl glucoside is a compound in which glucose (saccharides) and a higher alcohol are glucoside-bonded, and the alkyl chain length is preferably 6 to 22, more preferably 6 to 18, and even more preferably 8 to 14, . The alkyl glucosides having the condensed saccharides, which may be condensed with each other, are sometimes referred to as alkyl polyglucosides, but the alkyl glucosides of the present invention are used in the sense of including alkyl polyglucosides.

It is preferable to use an alkyl glucoside having a degree of sugar conversion of 1.0 to 10.0, more preferably 1.0 to 5.0, and still more preferably 1.0 to 3.0 in the alkyl glucoside.

Specific examples of the alkyl glucoside include octyl glucoside, decyl glucoside, lauryl glucoside and the like. Or a mixture thereof.

(water)

Examples of the water used in the present invention include ion-exchanged water (deionized water), pure water, ultrapure water and distilled water. In order to avoid incorporation of harmful impurities into the polishing composition, the purity of water can be increased by removing impurity ions by an ion exchange resin, removing impurities by a filter, and distilling.

(Other components)

The polishing composition of the present invention may contain other components as long as the object of the present invention is not impaired. Examples of such other components include known additives that can be used in water-soluble polymers other than HEC, chelating agents, organic acids, organic acid salts, inorganic acids, inorganic acid salts, preservatives, antifungal agents and other polishing compositions.

Examples of the water-soluble polymer other than HEC include polyethylene glycol (polyethylene oxide), polypropylene glycol, random copolymer of ethylene oxide and propylene oxide, block copolymer of ethylene oxide and propylene oxide, polyoxyalkylene alkyl ether , And polyoxyalkylene sorbitan fatty acid esters. Particularly, polyethylene glycol and polypropylene glycol are preferable. These may be used singly or in combination of two or more kinds, and two or more kinds of the same kinds of different molecular weights may be used. The average molecular weight thereof is preferably 300 to 30,000.

When the water-soluble polymer other than HEC is contained as the other component, the content thereof is preferably 0.00001 to 0.1 mass%, more preferably 0.0001 to 0.01 mass% with respect to the total composition. In particular, it is preferable to use at least one compound selected from polyethylene glycol and polypropylene glycol. In this case, the polyethylene glycol is 0.0001 to 0.1% by mass, preferably 0.0001 to 0.01% by mass, based on the entire composition, and the polypropylene glycol is used in an amount of 0.00001 to 0.01% by mass, preferably 0.00001 to 0.005% to be. The concentration ratio of the two is preferably polyethylene glycol / polypropylene glycol = 1 to 100, more preferably 1 to 10. The average molecular weight of the polyethylene glycol is preferably from 1,000 to 30,000, more preferably from 3,000 to 10,000. The average molecular weight of the polypropylene glycol is preferably 300 to 5000, more preferably 300 to 2000. The average molecular weight of polyethylene glycol and polypropylene glycol can be determined from the hydroxyl value.

The amount ratio of the at least one organic compound selected from the group consisting of (A) the abrasive grains, (B) the water-soluble alkali compound, (C) the hydroxyethyl cellulose and (D) the alkyl glucoside and the alkanolamide constituting the polishing composition of the present invention (A) is preferably 0.002 to 0.5% by mass, more preferably 0.01 to 0.2% by mass with respect to 1% by mass of the abrasive (A), and (C) the hydroxyethyl cellulose is (A) Is preferably 0.002 to 0.5% by mass, more preferably 0.01 to 0.2% by mass with respect to 1% by mass of the abrasive grains, and the organic compound component (D) is preferably 0.0002 to 0.2% by mass relative to 1% Is preferably 0.001 to 0.1% by mass.

The content of each component in the polishing composition of the present invention when used in polishing is preferably 0.01 to 2.0% by mass, and more preferably 0.05 to 1.0% by mass (A) of the abrasive grains (A) (C) 0.001 to 0.1 mass%, preferably 0.005 to 0.05 mass%, (D) the organic compound component is 0.00001 to 0.1 mass%, more preferably 0.001 to 0.05 mass% To 0.05% by mass, preferably 0.0001% to 0.02% by mass.

The method for producing the polishing composition of the present invention is not particularly limited and includes at least one of (A) an abrasive grain, (B) a water-soluble alkali compound, (C) hydroxyethyl cellulose, (D) an alkyl glucoside and an alkanolamide (E) water, and optionally, an optional component.

For example, a polishing composition concentrate can be prepared by mixing at least one organic compound selected from a slurry of abrasive grains, a solution of hydroxyethylcellulose dissolved in water in advance, water, alkyl glucosides and alkanolamides .

From such a procedure, a concentrate of polishing composition is obtained from the viewpoint of lowering the manufacturing, storage and transportation costs, and diluted with water at a predetermined dilution rate immediately before polishing the silicon wafer, so that it can be produced as a desired polishing composition .

The content of each component in the step of polishing composition concentrate is, for example, 1 to 30 mass%, preferably 2 to 20 mass% (B) of the abrasive grains (A) relative to the whole polishing composition concentrate, (D) a water-soluble alkaline compound is contained in an amount of 0.01 to 2.0 mass%, preferably 0.1 to 1.0 mass%, (C) May be 0.001 to 1.0% by mass, preferably 0.005 to 0.5% by mass.

The polishing composition of the present invention can be used as an abrasive for various abrasive articles to be polished. Particularly, it can be suitably used for a polishing process of a silicon wafer in the process of manufacturing a semiconductor substrate. Furthermore, the polishing composition of the present invention is a polishing composition suitable for final polishing of bare silicon wafers for the production of semiconductor substrates.

Example

Hereinafter, the present invention will be described more specifically by examples. The present invention is not limited at all by these examples.

The measurement and test methods used in the present invention are as follows.

(1) Measurement of average primary particle diameter of abrasive grains

The average primary particle diameter of the abrasive grains (colloidal silica) is determined by the following formula [1], which is the specific surface area measured by the BET method (nitrogen adsorption)

Average primary particle diameter (nm) = 2672 / specific surface area (m 2 / g) [1]

. The measurement of the specific surface area by the BET method was carried out using Macsorb HM model-1201 manufactured by Matsutec Co., Ltd. The sample for measurement was prepared by heating and drying a slurry containing colloidal silica on a hot plate, and finely blowing it with induction.

(2) Measurement of average secondary particle diameter of abrasive grains

The average secondary particle diameter of the abrasive grains (colloidal silica) is represented by the cumulative 50% particle diameter D50 of the particle size distribution (volume representation) measured by the dynamic light scattering method. Further, one-half of the difference between the cumulative 84% particle diameter and the cumulative 16% particle diameter was defined as SD. The particle size distribution measurement by the dynamic light scattering method was performed using Microtrac model UPA-UT151 manufactured by Nikkiso Co., Ltd.

The sample for measurement was prepared by diluting a slurry containing colloidal silica with ion-exchanged water so as to have a silica concentration of 0.1%.

(3) Measurement of average molecular weight of HEC

The number average molecular weight (Mn) and the weight average molecular weight (Mw) of HEC were measured by the GPC method.

GPC measurement was carried out under the following conditions and conditions.

GPC apparatus: SCL-10A manufactured by Shimadzu Corporation

Column: TSKgel GMPWXL manufactured by Toso Co., Ltd. (× 1)

+ TSKgel G2500PWXL (× 1)

Eluent: 0.1 mol / kg NaCl, 20% methanol, residual pure water

Flow rate: 0.6 mL / min

Detection method: RI + UV (254 nm)

Standard material: Polyethylene oxide

(4) Etching test

A 4-inch silicon wafer having a p-type, a crystal face (100), a resistivity of 1 to 10? 占 cm m and a thickness of 525 占 퐉 was cut into a square of 25 mm x 25 mm on one side. This wafer piece was immersed in 1% hydrofluoric acid for 10 minutes in order to remove the oxide film on the surface. After removal from hydrofluoric acid, the surface was rinsed with ion-exchanged water to confirm that the surface sufficiently repelled water (wettability 0%). After wiping off the surface of the wafer piece to remove moisture, the weight was weighed and immersed in 20 g of polishing composition concentrate. The wafer piece was taken out one day, and the surface was rinsed with ion-exchange water, and then the surface was wiped to remove moisture, weighed, and returned to the concentrate of the original polishing composition. The amount of decrease from the original weight was defined as the etching amount. (Mg) - the weight of the last day (mg)) / the number of days elapsed until the last day (mg / day) Day) was defined as an average etching amount (mg / day).

(5) Polishing test 1

A polishing test was conducted using a polishing composition prepared by diluting a concentrate of polishing composition with ion-exchanged water at a predetermined dilution rate.

The polishing test 1 was carried out under the following conditions and conditions.

Grinder: LGP-15S-I manufactured by Micro Kiken Co.

Wafer: 4 inch silicon wafer

(P-type, resistivity of 1 to 10? Cm, crystal plane 100)

Surface pressure: 0.12 kgf / cm 2

Wafer rotation speed: 50 rpm

Pad: SURFIN SSWI manufactured by Fujimi

Pad rotation speed: 50 rpm

Grinding slurry feed rate: 100 mL / min

Polishing time: 10 minutes

The amount of polishing was obtained from the change in weight of the wafer before and after polishing.

The wettability (%) of the surface is the sum of the area of the surface of the wafer covered with water / the total area (%) of the surface of the wafer, Was visually confirmed at two timings after ion-exchanged water was added.

(6) Polishing test 2

Polishing Test 2 was conducted under the following apparatuses and conditions.

Grinding machine: Okamoto Kosakuki Co., Ltd. Caiseisakusho Co., Ltd. PNX-332B

Wafer: 12 inch silicon wafer

(P-type, resistivity 1 to 100? Cm, crystal plane 100)

Surface pressure: 0.12 kgf / cm 2

Wafer rotation speed: 30 rpm

Pad: Foamed urethane

Pad rotation speed: 30 rpm

Grinding slurry feed rate: 100 mL / min

Polishing time: predetermined time (expressed as x 1), predetermined time twice (expressed as x 2)

Particle and haze measurements: Surfscan SP3 made by KLA-Tencor

(Production Example 1)

&Lt; Preparation of colloidal silica slurry >

A slurry of the colloidal silica used as the abrasive grains was prepared by the method described in the Example of 4712556.

Further, filtration through 0.5 탆 of a filter was performed to obtain a colloidal silica slurry having a silica concentration of 17.0 wt% and an NH ₃ concentration of 1560 ppm. The particle diameter of the obtained colloidal silica was 19.0 nm in average primary particle diameter, 31.6 nm in average secondary particle diameter

(SD = 8.8 nm, CV = 0.28).

(Production Example 2)

&Lt; Production of HEC solution >

15 kg of HEC (SP200 manufactured by Daicel Fine Chem Co., Ltd., weight average molecular weight: 120,000) was added and dissolved in 585 kg of ion-exchanged water little by little to prepare 600 kg of a 2.5% crude HEC solution. This sediment liquid was passed through a cation exchange resin (Amberlite200CT (H) -HG made by Organo Co., Ltd.) column to remove metal impurities. After the column treatment, 5.3 kg of 25% NH ₃ water and 200 kg of ion-exchanged water were added, and further 0.5 탆 filter filtration was performed. Thus, 732 kg of a HEC solution with an HEC concentration of 1.7 wt% and an NH ₃ concentration of 1650 ppm was obtained.

(Production Example 3)

&Lt; Preparation of polishing composition (polishing slurry) >

A colloidal silica slurry prepared in Preparation Example 1, a HEC solution prepared in Preparation Example 2, and a surfactant selected from NH ₃ water, ion-exchanged water and the surfactants shown in Table 1, and a PEG / PPG mixed solution Were mixed in a predetermined amount to prepare a polishing composition concentrate.

The polishing composition concentrate was diluted with ion-exchanged water at a predetermined dilution rate immediately before polishing to prepare a polishing composition.

(Example 1)

Depending on the production process of Production Example 3, as a surfactant, using the AA-A surface active agent 1% solution 5.00 parts by weight of a colloidal silica slurry of 52.9 parts by weight of HEC solution was 17.6 parts by weight, 4% NH ₃ water 2.21 parts by weight And 22.2 parts by weight of water were mixed to prepare an abrasive composition concentrate. The concentrations of the surfactant, abrasive grains, NH ₃ and HEC contained in the obtained polishing composition concentrate are shown in Table 2.

Subsequently, the resulting polishing composition concentrate was diluted with ion exchange water to the dilution ratio shown in Table 2 to prepare a polishing composition.

The obtained polishing composition concentrate and polishing composition were subjected to an etching test, a polishing test 1 and a wettability test. The results are shown in Table 2.

In the etching test, the smaller the etching amount, the better the average etching amount (mg / day) was judged to be less than 0.10 mg, and the judgment of 0.10 mg or more was judged as defective.

In Polishing Test 1, the higher the polishing amount, the better. In this condition, the polishing amount of 0.5 mg or more was judged to be good and less than 0.5 mg was judged to be defective.

The wettability immediately after polishing and the wettability test after water rinse were more preferable to 100%, and 90% or more was judged to be good and less than 90% to be judged to be inferior.

(Example 2)

For Example 1, the mixing ratio of each component, a surfactant, 1% solution 2.50 parts by weight of a colloidal silica slurry with 54.1 parts by weight of HEC solution was 21.5 parts by weight, 4% NH ₃ water 2.88 parts by weight, and water 19.0 wt. , The concentrate for polishing composition and the polishing composition were prepared in the same manner.

The obtained polishing composition concentrate and polishing composition were subjected to an etching test, a polishing test 1 and a wettability test. The results are shown in Table 2.

(Examples 3 and 4)

A concentrate of the polishing composition and a concentrate of the polishing composition were prepared in the same manner as in Examples 1 and 2, except that each of the surfactants was replaced with AG-A.

The obtained polishing composition concentrate and polishing composition were subjected to an etching test, a polishing test 1 and a wettability test. The results are shown in Table 2.

(Example 5)

A concentrate for polishing composition and a concentrate for polishing composition were prepared in the same manner as in Example 1 except that the surfactant was replaced with AG-B.

The obtained polishing composition concentrate and polishing composition were subjected to an etching test, a polishing test 1 and a wettability test. The results are shown in Table 2.

(Comparative Examples 1 and 2)

The polishing composition concentrates and polishing composition concentrates were prepared in the same manner as in Examples 1 and 2, except that the use of the surfactant was omitted, and Comparative Examples 1 and 2 were prepared. The obtained polishing composition concentrate and polishing composition were subjected to an etching test, a polishing test 1 and a wettability test. The results are shown in Table 2.

(Comparative Example 3)

A polishing composition concentrate and a polishing composition concentrate were prepared in the same manner as in Example 1, except that the surfactant was replaced with PEG, and an etching test, a polishing test 1 and a wettability test were conducted. The results are shown in Table 2.

(Comparative Examples 4 and 5)

A concentrate for polishing composition and a concentrate for polishing composition were prepared in the same manner as in Examples 1 and 2, except that the surfactant was replaced by POEAE-A, respectively, and Polishing Test 1 and wettability test were conducted. The results are shown in Table 2. The etching test is omitted.

(Comparative Examples 6 to 8)

(Comparative Example 6), POEAE-C (Comparative Example 7), or POEAPE-A (Comparative Example 8) instead of the surfactant solution in Example 1 with the amount of the surfactant solution changed to 1.00 parts by weight A polishing composition concentrate and a polishing composition concentrate were prepared in the same manner as above except that polishing test 1 and wettability test were conducted. The results are shown in Table 2. The etching test is omitted.

In the polishing composition concentrate or polishing composition (Examples 1 to 5) to which alkanolamide or alkyl glucoside was added, both of the tests were good.

In Comparative Examples 1 to 8, the etching test, the polishing test 1 or the wettability test were separated.

(Example 6)

4.50 parts by weight of a 1% solution of a surfactant, 54.1 parts by weight of a colloidal silica slurry, 21.5 parts by weight of a HEC dissolving solution, 2.88 parts by weight of 4% NH3 water, 4.50 parts by weight of a PEG / PPG mixed solution and 12.5 parts by weight of water were mixed to prepare a polishing composition concentrate. The concentrations of the surfactant, abrasive grains, NH ₃ , HEC and other components contained in the obtained polishing composition concentrate are shown in Table 3.

The PEG / PPG mixed solution used in this Example is an aqueous solution containing 8000 ppm of PEG-6000S manufactured by Sanyo Chemical Industries, Ltd., and 2000 ppm of Newpol PP1000 manufactured by Sanyo Chemical Industries, Ltd.

Subsequently, the resulting polishing composition concentrate was diluted with ion exchange water to the dilution ratio shown in Table 3 to prepare a polishing composition.

Polishing Test 2 was conducted using the resulting polishing composition concentrate and polishing composition. The results are shown in Table 3.

In Polishing Test 2, the haze is represented by a relative value obtained by setting the value of Comparative Example 9 below to 100. [ (?), It was judged that the ratio was 95 or more and 105 or less (?), And 105 or more was poor (x).

The particle (26 nm or more) is represented by a relative value obtained by setting the value of Comparative Example 9 below as 100. It was judged that it was good (?) When it was less than 90, was possible (O) when it was less than 90 and less than 200, and was bad (X) when it was more than 200.

(Examples 7 to 8)

A polishing composition concentrate and a polishing composition were prepared in the same manner as in Example 6 except that the surfactant was replaced with AG-A (Example 7) or AG-B (Example 8), and Polishing Test 2 . The results are shown in Table 3.

(Comparative Example 9)

A polishing composition concentrate and a polishing composition were prepared in the same manner as in Example 6, except that the use of the surfactant was omitted, and Polishing Test 2 was carried out. The results are shown in Table 3.

From the results of Table 3, it was found that all the haze were good (⊚) and the particles were all (◯) or more in the polishing compositions (Examples 6 to 8) to which alkanolamide or alkyl glucoside was added.

The polishing composition provided by the present invention is excellent in wafer protection ability (alkali-etch resistance), and as a result, a good reduction in haze value can be expected.

According to the present invention, since a polishing composition capable of having appropriate hydrophilicity on the surface of a silicon wafer immediately after polishing is provided, it is easy to wash away and remove fine silicon debris generated during abrasive grain polishing. As a result, there is provided a polishing composition capable of realizing a satisfactory surface quality.

The polishing composition provided by the present invention is a polishing composition that is excellent in wafer protecting ability (alkali-etch resistance) and can impart appropriate wettability to a wafer after polishing.

The polishing composition provided by the present invention is used as an abrasive for various kinds of abrasive to be polished, and can be suitably used particularly in a polishing process of a silicon wafer in the process of manufacturing a semiconductor substrate. Furthermore, the polishing composition of the present invention is a polishing composition suitable for final polishing of bare silicon wafers for the production of semiconductor substrates.

Claims (8)

(A) Grain
(B) a water-soluble alkali compound
(C) a hydroxyethylcellulose having a weight average molecular weight of 500,000 or less
(D) at least one organic compound selected from alkyl glucosides and alkanolamides
And
(E) Water
. &Lt; / RTI &gt; The polishing composition according to claim 1, wherein the abrasive grains are colloidal silica. 3. The polishing composition according to claim 2, wherein the colloidal silica has an average primary particle diameter of 5 to 100 nm as determined by a nitrogen adsorption method (BET method). 4. The polishing composition according to claim 2 or 3, wherein the colloidal silica is a cocoon-shaped colloidal silica obtained by reacting a condensate of an alkoxysilane with water in the presence of an ammonia or ammonium salt catalyst. The coating composition according to any one of claims 1 to 4, wherein the composition contains 0.01 to 2.0% by weight of (A) abrasive grains, (B) 0.0001 to 0.1% by weight of a water-soluble alkali compound, (C) 0.001 of hydroxyethylcellulose To 0.1 mass%, and (D) the organic compound component is 0.00001 to 0.05 mass%. The polishing composition according to any one of claims 1 to 5, further comprising at least one compound selected from polyethylene glycol and polypropylene glycol. The polishing composition according to any one of claims 1 to 6, which is used for polishing a silicon wafer. A polishing method for a silicon wafer comprising a step of polishing a silicon wafer using the polishing composition according to any one of claims 1 to 7.