WO2015068672A1 - Wetting agent and polishing composition for semiconductor - Google Patents

Wetting agent and polishing composition for semiconductor Download PDF

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Publication number
WO2015068672A1
WO2015068672A1 PCT/JP2014/079161 JP2014079161W WO2015068672A1 WO 2015068672 A1 WO2015068672 A1 WO 2015068672A1 JP 2014079161 W JP2014079161 W JP 2014079161W WO 2015068672 A1 WO2015068672 A1 WO 2015068672A1
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Prior art keywords
water
soluble polymer
wetting agent
polishing
meth
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PCT/JP2014/079161
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French (fr)
Japanese (ja)
Inventor
貴之 竹本
直彦 斎藤
松崎　英男
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東亞合成株式会社
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Priority to JP2015546633A priority Critical patent/JP6129336B2/en
Publication of WO2015068672A1 publication Critical patent/WO2015068672A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B37/00—Lapping machines or devices; Accessories
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B37/00—Lapping machines or devices; Accessories
    • B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
    • B24B37/042—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor
    • B24B37/044—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor characterised by the composition of the lapping agent
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09G—POLISHING COMPOSITIONS; SKI WAXES
    • C09G1/00—Polishing compositions
    • C09G1/06—Other polishing compositions
    • C09G1/14—Other polishing compositions based on non-waxy substances
    • C09G1/16—Other polishing compositions based on non-waxy substances on natural or synthetic resins
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02002—Preparing wafers
    • H01L21/02005—Preparing bulk and homogeneous wafers
    • H01L21/02008—Multistep processes
    • H01L21/0201—Specific process step
    • H01L21/02024—Mirror polishing

Definitions

  • the present invention relates to a wetting agent for semiconductors and a polishing composition, and more particularly to a wetting agent for semiconductors and a polishing composition used for final polishing of a silicon wafer.
  • Semiconductor devices using a silicon wafer as a substrate are widely used in information communication equipment such as personal computers and mobile phones, and digital home appliances such as digital cameras and televisions.
  • information communication equipment such as personal computers and mobile phones
  • digital home appliances such as digital cameras and televisions.
  • Wafers prior to device formation have defects such as smoothness and scratches. The so-called intactness requirement that does not exist is becoming increasingly severe.
  • CMP Chemical Mechanical Polishing
  • a polishing process called CMP (Chemical Mechanical Polishing)
  • CMP Chemical Mechanical Polishing
  • a polishing composition containing fine abrasive grains and a basic compound is used. While supplying this polishing composition to the surface of the polishing pad, the surface is polished by relatively moving the polishing pad in pressure contact with the wafer as the object to be polished.
  • the mechanical polishing by the abrasive grains and the chemical polishing by the basic compound proceed simultaneously, the wafer surface can be smoothed over a wide range with high accuracy.
  • high-precision smoothing is realized by performing polishing in 3 to 4 stages.
  • the polishing rate tends to be regarded as important.
  • the haze and COP Crystal Originated Particles of the wafer surface are suppressed, and further, agglomerated abrasive grains, polishing pad debris, and polishing are removed. Emphasis is also placed on the prevention of contamination caused by the adhesion of so-called particles such as silicon powder.
  • Patent Document 1 discloses a polishing composition comprising a water-soluble polymer compound having a molecular weight of 100,000 or more and water-soluble salts.
  • Patent Document 2 discloses a polishing composition containing a specific polyacrylamide derivative.
  • Patent Document 3 describes a polishing composition containing a water-soluble polymer compound, and describes that a cellulose derivative or polyvinyl alcohol can be used as the water-soluble polymer compound.
  • JP-A-2-158684 Japanese Patent No. 4915736 JP-A-11-116942
  • Patent Document 1 discloses only a homopolymer of N, N-dimethylacrylamide in the examples as specific examples of the polyacrylamide derivative, but the dispersibility of the abrasive grains is not sufficient.
  • the present invention has been made in view of such circumstances, and provides a wetting agent for semiconductor and a polishing composition effective in smoothing the wafer surface with high accuracy and effective in suppressing COP in surface polishing of a silicon wafer. It is an object to do.
  • the present inventors include a water-soluble polymer mainly composed of a structural unit derived from N- (meth) acryloylmorpholine and having substantially no cationic group. It has been found that the use of a wetting agent for semiconductors has an effect on smoothing the wafer surface after polishing and suppressing COP, and the present invention has been completed.
  • the present invention is as follows. [1] A semiconductor wetting agent containing a water-soluble polymer having 50 to 100 mol% of a structural unit derived from N- (meth) acryloylmorpholine and substantially free of a cationic group. [2] The semiconductor wetting agent according to [1], wherein the structural unit derived from N- (meth) acryloylmorpholine is 100 mol%. [3] The semiconductor wetting agent as described in [1] or [2] above, wherein the water-soluble polymer has a number average molecular weight in the range of 1,000 to 300,000.
  • [4] The method for producing a water-soluble polymer according to any one of [1] to [3], wherein a nonionic and / or anionic polymerization initiator is used as a polymerization initiator, and N—
  • a method for producing a water-soluble polymer comprising radically polymerizing 50 to 100 mol% of (meth) acryloylmorpholine and 0 to 50 mol% of another monomer.
  • a polishing composition comprising the semiconductor wetting agent according to any one of [1] to [3], water, abrasive grains, and an alkali compound.
  • the semiconductor wetting agent of the present invention has excellent adsorptivity to the wafer surface after polishing. For this reason, by using the polishing composition containing the semiconductor wetting agent, it is possible to increase the smoothness of the polished wafer surface and to suppress the COP because of excellent etching resistance. Furthermore, since the dispersibility of silica is also good, there are few scratches and surface roughness due to the agglomerated silica abrasive grains, and a wafer surface with excellent scratch resistance can be obtained.
  • (meth) acryl means acryl and methacryl
  • (meth) acrylate means acrylate and methacrylate
  • the “(meth) acryloyl group” means an acryloyl group and a methacryloyl group.
  • the wetting agent for semiconductors of the present invention contains a water-soluble polymer having 50 to 100 mol% of structural units derived from N- (meth) acryloylmorpholine and substantially free of a cationic group.
  • the structural unit derived from N- (meth) acryloylmorpholine is preferably in the range of 70 to 100 mol%, more preferably in the range of 90 to 100 mol%, and most preferably 100 mol%.
  • the structural unit derived from N- (meth) acryloylmorpholine has good adsorptivity to the wafer surface and excellent hydrolysis resistance.
  • the wetting agent for semiconductors containing a water-soluble polymer mainly composed of the structural unit exhibits excellent alkali resistance even when a polishing composition is formed with an alkali compound or the like, and the polishing composition The object exhibits good etching resistance.
  • N- (meth) acryloylmorpholine in addition to N- (meth) acryloylmorpholine, other monomers copolymerizable therewith may be used.
  • Other monomers are not particularly limited.
  • Acrylic acid alkyl esters Unsaturated acids such as (meth) acrylic acid, crotonic acid, maleic acid, itaconic acid and fumaric acid and their alkyl esters; Unsaturated acid anhydrides such as maleic anhydride; 2-acrylamide -Sulphonic acid group-containing monomers such as 2-methylpropanesulfonic acid and salts thereof; methyl (meth) acrylamide, ethyl (meth) acrylamide, n-propyl (meth) acrylamide, iso
  • the amount of these monomers used in the water-soluble polymer ranges from 0 to 50 mol%, preferably from 0 to 30 mol%, more preferably from 0 to 10 mol%.
  • the amount of other monomers used exceeds 50 mol%, the amount of N- (meth) acryloylmorpholine used is less than 50 mol%, so that the adsorptivity to the wafer is not sufficient, and the semiconductor wetting of the present invention The effect of the agent may not be obtained.
  • the water-soluble polymer of the present invention is substantially free of a cationic group. Since the cationic group is introduced by a monomer having a cationic group such as a quaternary ammonium base, an initiator, or the like, in the present invention, “substantially does not contain a cationic group” means that these components are raw materials. Means not using as.
  • the number average molecular weight (Mn) of the water-soluble polymer is preferably in the range of 1,000 to 300,000, more preferably in the range of 1,500 to 150,000, still more preferably 2,000 to The range is 100,000. If the number average molecular weight (Mn) is 1,000 or more, the wettability of the wafer is sufficiently secured, and if it is 300,000 or less, the dispersibility of the abrasive grains can be secured.
  • the number average molecular weight can be measured in terms of polystyrene using GPC (gel permeation chromatography, for example, HLC-8220, manufactured by Tosoh Corporation).
  • the molecular weight distribution (PDI) of the water-soluble polymer is narrow.
  • the value obtained by dividing the weight average molecular weight (Mw) by the number average molecular weight (Mn) is preferably 4.0 or less, more preferably 3.5 or less, and 3.0 or less. More preferably.
  • the molecular weight distribution (PDI) is 4.0 or less, sufficient wettability is exhibited, and deterioration in dispersibility of (silica) abrasive grains caused by a high molecular weight body can be avoided.
  • the water-soluble polymer in the present invention uses a nonionic and / or anionic polymerization initiator as a polymerization initiator in a polymerization solvent, N- (meth) acryloylmorpholine 50 to 100 mol%, and other monomers 0 It can be obtained by radical polymerization of ⁇ 50 mol%.
  • the polymerization method is not particularly limited, but the solution polymerization method is preferable because a water-soluble polymer can be obtained in a uniform state.
  • the polymerization solvent in the solution polymerization water or a mixed solvent composed of water and an organic solvent can be used.
  • the organic solvent include methanol, ethanol, isopropanol, acetone, and methyl ethyl ketone, and one or more of these may be used in combination.
  • any known nonionic and / or anionic polymerization initiator may be used, and a radical polymerization initiator is particularly preferably used.
  • the radical polymerization initiator include persulfates such as sodium persulfate, potassium persulfate and ammonium persulfate, hydroperoxides such as t-butyl hydroperoxide, water-soluble peroxides such as hydrogen peroxide, methyl ethyl ketone, and the like.
  • Ketone peroxides such as peroxide and cyclohexanone peroxide, dialkyl peroxides such as di-t-butyl peroxide and t-butylcumyl peroxide, t-butyl peroxypivalate, t-hexyl peroxypivalate, etc.
  • Oil-soluble peroxides such as peroxyesters, 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate, 2,2′-azobis [2- ( 2-Imidazolin-2-yl) propane], 2,2′-azobis [2- Water-soluble azo compounds such as til-N- (2-hydroxyethyl) propionamide] and 4,4′-azobis-4-cyanovaleric acid, 2,2′-azobisisobutyronitrile, 2,2′- Examples thereof include oil-soluble azo compounds such as azobis (2,4-dimethylvaleronitrile) and 2,2′-azobis (2-methylbutyronitrile).
  • the radical polymerization initiator may be used alone or in combination of two or more.
  • persulfates and water-soluble azo compounds are preferable, and water-soluble azo compounds are particularly preferable because the polymerization reaction can be easily controlled.
  • the ratio of the radical polymerization initiator used is not particularly limited, but is preferably 0.1 to 10% by mass based on the total weight of all monomers constituting the entire water-soluble polymer. A ratio of 1 to 5% by mass is more preferable, and a ratio of 0.2 to 3% by mass is more preferable.
  • the polymerization of the water-soluble polymer may be carried out in the presence of a chain transfer agent as necessary.
  • a chain transfer agent By using a chain transfer agent, the molecular weight of the water-soluble polymer can be appropriately adjusted.
  • the chain transfer agent known ones can be used.
  • an alkylthiol compound having an alkyl group having 2 to 20 carbon atoms is preferable from the viewpoint of good adsorbability to a wafer, more preferably one having an alkyl group having 4 to 20 carbon atoms, More preferred are those having 6 to 20 alkyl groups.
  • the preferred amount is 0.1 to 10% by weight, more preferably 0.5 to 5% by weight, based on the amount of all monomers.
  • the reaction temperature during polymerization is preferably 30 to 100 ° C, more preferably 40 to 90 ° C, and further preferably 50 to 80 ° C.
  • the semiconductor wetting agent of the present invention comprises the water-soluble polymer and water. It is preferable to use high-purity water so as not to impair the effect as a wetting agent. Specifically, it is preferable to use pure water, ultrapure water, or distilled water from which foreign ions are removed by filtration after removing impurity ions with an ion exchange resin.
  • the wetting agent may contain an organic solvent such as alcohol and ketone having high miscibility with water.
  • the ratio of the water-soluble polymer in the wetting agent for semiconductor is not particularly limited as long as it is a viscosity that can be easily handled as an aqueous solution, but is preferably in the range of 1 to 50% by mass, more preferably in the range of 3 to 40% by mass. The range of 30% by mass is more preferable.
  • the water-soluble polymer in the present invention is excellent in adsorptivity to the wafer surface and the like, and particularly exhibits high adsorptivity to the wafer surface in a state where the oxide film is completely removed. For this reason, when the semiconductor wetting agent of the present invention is used in the wafer surface treatment process, the smoothness of the polished wafer surface can be improved, and contamination caused by COP and particle adhesion can be reduced. The following mechanism is assumed as a reason why these effects can be obtained. Regarding the smoothness of the wafer surface, the water-soluble polymer in the semiconductor wetting agent is adsorbed on the wafer surface, so that the friction between the wafer surface and the abrasive grains is reduced in the mechanical polishing of CMP. For this reason, it is considered that the minute unevenness formed on the wafer surface by mechanical polishing is reduced and the smoothness is improved.
  • the polishing composition in mechanical polishing, the polishing composition is supplied to the wafer surface and the polishing pad is pressed against the wafer surface and rotated to physically polish the wafer surface. Therefore, the polishing pad is pressed against a portion other than the COP on the wafer surface and polished in a direction perpendicular to the wafer surface. As the mechanical polishing proceeds, the COP gradually decreases, and the COP disappears when the wafer surface is polished beyond the depth. Therefore, it is considered that the mechanical polishing shows the effect of reducing the number of COPs and the size thereof.
  • chemical polishing the polishing composition enters the COP during polishing, and the basic compound corrodes or etches the inside of the COP.
  • the polishing is performed in the direction perpendicular to the inner wall of the COP, it is considered that the COP on the wafer surface increases with the progress of chemical polishing.
  • the water-soluble polymer adsorbed on the wafer surface has a function of suppressing chemical polishing more than mechanical polishing. It is presumed that this tendency becomes stronger as the water-soluble polymer adsorbability to the wafer becomes higher, and as a result, a wafer surface having high smoothness and low COP can be obtained.
  • the surface is hydrophilized. Therefore, contamination due to adhesion of particles during polishing can also be prevented.
  • the present invention also provides a method for polishing a wafer by adsorbing such a water-soluble polymer to the wafer.
  • the water-soluble polymer is supplied as a semiconductor wetting agent containing water-soluble polymer and water, and includes the water-soluble polymer of the present disclosure, water, abrasive grains, and an alkali compound
  • the form which supplies polishing composition with respect to a wafer is contained.
  • the polishing composition of the present invention comprises the semiconductor wetting agent, water, abrasive grains, and an alkali compound.
  • the ratio of the semiconductor wetting agent in the polishing composition is not particularly limited, but it is preferable that the polishing composition has an appropriate viscosity for handling in CMP and adsorbing to the wafer surface.
  • the specific viscosity of the polishing composition is preferably in the range of 0.1 to 10 mPa ⁇ s, more preferably in the range of 0.3 to 8 mPa ⁇ s, and 0.5 to 5 mPa ⁇ s. More preferably, it is in the range.
  • the water-soluble polymer is preferably used in a range of 0.001 to 10% by mass, more preferably in a range of 0.005 to 5% by mass with respect to the entire abrasive composition.
  • colloidal silica or the like can be used as the abrasive grains.
  • its content in the polishing composition is preferably 0.1 to 50% by mass, more preferably 1 to 30% by mass, and 3 to 20% by mass. More preferably it is. If the usage-amount of colloidal silica is 0.1 mass% or more, the polishing rate of mechanical polishing will become favorable. Moreover, if it is 50 mass% or less, the dispersibility of an abrasive grain is hold
  • the average particle size of the corridal silica is appropriately selected from the required polishing rate and the smoothness of the polished wafer surface, but is generally in the range of 2 to 500 nm, preferably in the range of 5 to 300 nm. A range of ⁇ 200 nm is more preferable.
  • the alkali compound is not particularly limited as long as it is a water-soluble alkali compound, and alkali metal hydroxides, amines, ammonia, quaternary ammonium hydroxide salts, and the like can be used.
  • alkali metal hydroxide include potassium hydroxide, sodium hydroxide, rubidium hydroxide and cesium hydroxide.
  • amines include triethylamine, monoethanolamine, diethanolamine, triethanolamine, diisopropanolamine, ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylpentamine, and tetraethylpentamine.
  • the quaternary ammonium hydroxide salt examples include tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide. Among these, ammonia or a quaternary ammonium hydroxide salt is preferable from the viewpoint of less contamination of the semiconductor substrate.
  • the polishing composition of the present invention is preferably adjusted to have a pH of 8 to 13 by adding the alkali compound. More preferably, the pH range is adjusted to 8.5-12.
  • an organic solvent various chelating agents, a surfactant, and the like can be added to the polishing agent composition as necessary.
  • E.R. ⁇ Etching resistance (E.R.)> After measuring the weight of the wafer cut to 3 ⁇ 6 cm with a glass cutter, it was immersed in a 3% hydrofluoric acid aqueous solution for 20 seconds to remove the oxide film on the wafer surface, and then washed with pure water for 10 seconds. This process was repeated until the wafer surface was completely water repellent. Next, an etching chemical solution was prepared by adding a semiconductor wetting agent to ammonia water having an ammonia: water weight ratio of 1:19 so that the concentration of the water-soluble polymer was 0.18 wt%. The wafer was completely immersed in an etching chemical solution and left to stand at 25 ° C. for 12 hours for etching. From the wafer weight change before and after etching, the etching rate (E.R.) was calculated according to the following formula.
  • ⁇ Wettability> The oxide film on the wafer surface was removed by the same method as etching resistance, and then immersed in a 0.18 wt% water-soluble polymer solution for 5 minutes. After immersion, the surface of the wafer was pulled up using a tweezers so as to be perpendicular to the liquid level, and the water-repellent distance from the end of the wafer at the time when 10 seconds had passed was visually confirmed, and judged according to the following criteria.
  • ⁇ Water repellent distance 5 to 10 mm
  • ⁇ Water repellent distance> 10mm
  • ⁇ Wafer appearance> The wafer surface after etching was performed by the same method as the etching resistance was visually confirmed, and judged according to the following criteria. ⁇ : No roughening on the surface ⁇ : The surface is slightly rough ⁇ : The surface is extremely rough
  • a monomer aqueous solution in which 700 parts of N-acryloylmorpholine (manufactured by Kojin Co., Ltd., hereinafter referred to as “ACMO”) was dissolved in 1600 parts of pure water was dropped from the monomer introduction tube over 1 hour to perform polymerization.
  • a chain transfer agent aqueous solution in which 1.4 parts of 2-mercaptoethanol (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 140 parts of pure water was dropped from another introduction tube over 1 hour. After completion of the dropwise addition of each aqueous solution of the monomer and the chain transfer agent, polymerization was further performed at 80 ° C. for 2 hours.
  • This polymer 1 had a number average molecular weight (Mn) of 24,000 and a molecular weight distribution (PDI) of 2.4.
  • the polymerization rate calculated from GC was 100%.
  • Production Example 2 The same operation as in Production Example 1 was carried out except that no chain transfer agent was used, and Polymer 2 was obtained.
  • the Mn of the polymer 2 was 120,000 and the PDI was 3.0.
  • the polymerization rate was 99%.
  • Production Example 3 Polymer 3 was obtained in the same manner as in Production Example 2 except that the amount of ACVA used as the initiator was changed to 0.5 part.
  • the Mn of the polymer 3 was 250,000 and the PDI was 3.3.
  • the polymerization rate was 99%.
  • Production Example 4 Polymer 4 was obtained in the same manner as in Production Example 1 except that the monomers used were changed to ACMO 630 parts (82 mol%) and acrylic acid 70 parts (18 mol%). The Mn of the polymer 4 was 25,000 and the PDI was 2.5. The polymerization rate was 99%.
  • Production Example 5 A polymer 5 was obtained in the same manner as in Production Example 1 except that the monomers used were changed to ACMO 560 parts (60 mol%) and acrylic acid 140 parts (40 mol%). The Mn of the polymer 5 was 25,000 and the PDI was 2.4. The polymerization rate was 99%.
  • Production Example 6 In Production Example 1, the initiator used was 2,2′-azobis [2- (2-imidazolin-2-yl) propane] disulfate dihydrate (manufactured by Wako Pure Chemical Industries, Ltd., trade name “VA-”). 046B ”) was changed to 0.6 part, and the same operation was performed except that the polymerization temperature was changed to 60 ° C to obtain a polymer 6. The Mn of the polymer 6 was 25,000 and the PDI was 2.5. The polymerization rate was 99%.
  • Production Example 7 Polymer 7 was obtained in the same manner as in Production Example 1, except that the monomer used was changed to 420 parts (43 mol%) of ACMO and 280 parts (57 mol%) of acrylic acid. The Mn of the polymer 7 was 24,000, and the PDI was 2.4. The polymerization rate was 98%.
  • Production Example 8 A polymer 8 was obtained in the same manner as in Production Example 1 except that the monomer used was changed to 700 parts of N, N-dimethylacrylamide. The Mn of the polymer 8 was 22,000, and the PDI was 2.2. The polymerization rate was 99%.
  • Example 1 Water was added so that the concentration of the polymer 1 which is a water-soluble polymer was 15% by mass to prepare a semiconductor wetting agent. About the obtained wetting agent for semiconductors, etching resistance, wettability, wafer appearance and alkali resistance were evaluated. The results obtained are shown in Table 2. Also, 10.0 g of colloidal silica dispersion (primary particle system 30-50 nm, silica solid content 10%) adjusted to pH 10.0 by adding ammonia water and 0.1 g of the above-mentioned wetting agent for semiconductor were added. A composition for an abrasive was obtained. The obtained composition for abrasives was evaluated for silica dispersibility, and Table 2 shows the results.
  • colloidal silica dispersion primary particle system 30-50 nm, silica solid content 10%
  • Example 2 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 2 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Example 3 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 3 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Example 4 Water was added so that the concentration of the polymer 1 which is a water-soluble polymer was 10.5% by mass to prepare a wetting agent for semiconductor. About the obtained wetting agent for semiconductors, etching resistance, wettability, wafer appearance and alkali resistance were evaluated. The results obtained are shown in Table 2. Moreover, the composition for abrasive
  • polishing agents was obtained by operation similar to Example 1 using the said semiconductor wetting agent. The obtained composition for abrasives was evaluated for silica dispersibility, and Table 2 shows the results.
  • Example 5 Water was added so that the concentration of the polymer 1 which is a water-soluble polymer was 4.5% by mass, and a semiconductor wetting agent was prepared. About the obtained wetting agent for semiconductors, etching resistance, wettability, wafer appearance and alkali resistance were evaluated. The results obtained are shown in Table 2. Moreover, the composition for abrasive
  • polishing agents was obtained by operation similar to Example 1 using the said semiconductor wetting agent. The obtained composition for abrasives was evaluated for silica dispersibility, and Table 2 shows the results.
  • Example 6 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that 50% of the polymer 1 and 50% of the polymer 2 were used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Example 7 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 4 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Example 8 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 5 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Comparative Example 1 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 6 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Comparative Example 2 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 7 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Comparative Example 3 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 8 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • Comparative Example 4 A wetting agent for semiconductor and an abrasive composition were prepared in the same manner as in Example 1 except that hydroxyethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight 90,000) was used as the water-soluble polymer. went. The evaluation results obtained are shown in Table 2.
  • Comparative Example 5 A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that PVP K30 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
  • HEC hydroxyethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight 90,000)
  • PVP K30 Polyvinylpyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.)
  • Examples 1 to 8 are experimental examples using the water-soluble polymer defined in the present invention, and because the adsorptivity to the wafer is high, results of excellent etching resistance, wettability and appearance to the wafer are obtained. ing. Moreover, it was confirmed that the silica dispersibility is excellent in the case of an abrasive composition. Above all, from the results of Examples 1, 7 and 8 using a water-soluble polymer having the same number average molecular weight and molecular weight distribution, Example 1 comprising 100 mol% of N- (meth) acryloylmorpholine is resistant to etching. The result was excellent, and the appearance on the wafer was also excellent.
  • Comparative Example 1 using a water-soluble polymer obtained with a cationic polymerization initiator resulted in a greatly inferior silica dispersibility.
  • Comparative Example 2 using a water-soluble polymer with a small proportion of N- (meth) acryloylmorpholine used was not sufficient in etching resistance and wettability, and the wafer appearance was inferior.
  • Comparative Example 3 is an experimental example using a water-soluble polymer composed of an amide compound different from N- (meth) acryloylmorpholine, but the results were greatly inferior in wettability and alkali resistance.
  • Comparative Examples 4 and 5 are examples using cellulose derivatives, which are water-soluble polymers used in conventional polishing compositions, but are satisfactory in terms of adsorptivity to the wafer surface and silica dispersibility. It wasn't.
  • the wetting agent for semiconductors of the present invention is excellent in the adsorptivity to the wafer surface after polishing, by using a polishing composition containing the wetting agent for semiconductors, the smoothness of the wafer surface after polishing is improved, and , COP can be suppressed. Furthermore, since the dispersibility of silica is also good, it is particularly useful as a composition for final polishing of silicon wafers.

Abstract

Provided is a wetting agent for a semiconductor, the wetting agent comprising a water-soluble polymer that is substantially cationic group-free and that has 50 to 100 mol % of structural units derived from N-(meth)acryloyl morpholine.

Description

半導体用濡れ剤及び研磨用組成物Semiconductor wetting agent and polishing composition
　関連出願の相互参照
　本出願は、２０１３年１１月８日に出願された日本国特許出願である特願２０１３－２３１７５２の関連出願であり、この日本出願に基づく優先権を主張するものであり、この日本出願に記載された全ての内容を参照により本明細書に組み込まれたものとする。
　本発明は、半導体用濡れ剤及び研磨用組成物に関し、さらに詳しくは、シリコンウェーハの仕上げ研磨等に用いられる半導体用濡れ剤及び研磨用組成物に関する。 This application is a related application of Japanese Patent Application No. 2013-231752, which is a Japanese patent application filed on November 8, 2013, and claims priority based on this Japanese application. All the contents described in this Japanese application are incorporated herein by reference.
The present invention relates to a wetting agent for semiconductors and a polishing composition, and more particularly to a wetting agent for semiconductors and a polishing composition used for final polishing of a silicon wafer.
　パソコン及び携帯電話等の情報通信機器、並びに、デジタルカメラ及びテレビ等のデジタル家電製品では、シリコンウェーハを基板とする半導体デバイスが広く用いられている。近年の半導体チップの高集積化、大容量化に伴い、半導体デバイスの加工精度は微細化の一途をたどっており、デバイス形成前のウェーハに対しては、その平滑性、及びキズ等の欠陥を有さないいわゆる無傷性の要求がますます厳しいものとなっている。 Semiconductor devices using a silicon wafer as a substrate are widely used in information communication equipment such as personal computers and mobile phones, and digital home appliances such as digital cameras and televisions. As semiconductor chips have been highly integrated and increased in capacity in recent years, the processing accuracy of semiconductor devices has been continually miniaturized. Wafers prior to device formation have defects such as smoothness and scratches. The so-called intactness requirement that does not exist is becoming increasingly severe.
　ウェーハの平滑化技術としては、ＣＭＰ（ケミカルメカニカルポリッシング：化学機械研磨）と呼ばれる研磨プロセスがよく用いられている。ＣＭＰによる平滑化処理では、微細な砥粒と塩基性化合物を含有した研磨用組成物が使用される。この研磨用組成物を研磨パッド表面に供給しながら、圧接した研磨パッドと被研磨物であるウェーハとを相対移動させて表面を研磨する。このとき、砥粒によるメカニカル研磨と、塩基性化合物によるケミカル研磨とが同時に進行することにより、広範囲にわたりウェーハ表面を高精度に平滑化することができる。
　一般に、ＣＭＰによるウェーハ研磨では、３～４段階の研磨を行うことにより、高精度の平滑化を実現している。第１段階および第２段階に行う１次研磨および２次研磨では、表面の平滑化を主な目的としていることから、研磨速度が重要視される傾向がある。これに対し、第３段階または第４段階の仕上げ研磨では、ウェーハ表面のヘイズ及びＣＯＰ（Ｃｒｙｓｔａｌ　Ｏｒｉｇｉｎａｔｅｄ　Ｐａｒｔｉｃｌｅｓ；結晶欠陥）の抑制、更には凝集した研磨砥粒、研磨パッド屑、研磨により除去されたシリコン粉といったいわゆるパーティクルの付着による汚染防止などについても重要視される。 As a wafer smoothing technique, a polishing process called CMP (Chemical Mechanical Polishing) is often used. In the smoothing treatment by CMP, a polishing composition containing fine abrasive grains and a basic compound is used. While supplying this polishing composition to the surface of the polishing pad, the surface is polished by relatively moving the polishing pad in pressure contact with the wafer as the object to be polished. At this time, since the mechanical polishing by the abrasive grains and the chemical polishing by the basic compound proceed simultaneously, the wafer surface can be smoothed over a wide range with high accuracy.
Generally, in wafer polishing by CMP, high-precision smoothing is realized by performing polishing in 3 to 4 stages. In primary polishing and secondary polishing performed in the first stage and the second stage, since the main purpose is to smooth the surface, the polishing rate tends to be regarded as important. On the other hand, in the final polishing in the third stage or the fourth stage, the haze and COP (Crystal Originated Particles) of the wafer surface are suppressed, and further, agglomerated abrasive grains, polishing pad debris, and polishing are removed. Emphasis is also placed on the prevention of contamination caused by the adhesion of so-called particles such as silicon powder.
　上記仕上げ研磨に使用される研磨用組成物としては、研磨用組成物中に水溶性高分子化合物を添加する方法が有効であることが知られている。特許文献１には、分子量１０万以上の水溶解性の高分子化合物及び水溶解性の塩類等を含有してなる研磨用組成物が開示されている。また、特許文献２には、特定のポリアクリルアミド誘導体を含む研磨用組成物が示されている。さらに、特許文献３には、水溶性高分子化合物を含む研磨用組成物が記載され、該水溶性高分子化合物として、セルロース誘導体又はポリビニルアルコールを用いることができる旨が記載されている。 It is known that a method of adding a water-soluble polymer compound to the polishing composition is effective as the polishing composition used for the above-described finish polishing. Patent Document 1 discloses a polishing composition comprising a water-soluble polymer compound having a molecular weight of 100,000 or more and water-soluble salts. Patent Document 2 discloses a polishing composition containing a specific polyacrylamide derivative. Furthermore, Patent Document 3 describes a polishing composition containing a water-soluble polymer compound, and describes that a cellulose derivative or polyvinyl alcohol can be used as the water-soluble polymer compound.
特開平２－１５８６８４号公報JP-A-2-158684 特許第４９１５７３６号公報Japanese Patent No. 4915736 特開平１１－１１６９４２号公報JP-A-11-116942
　しかし、特許文献１に記載の発明では、用いられる水溶解性高分子化合物のウェーハ表面への吸着性が十分ではなく、仕上げ研磨後のウェーハ表面のヘイズ及びＣＯＰが満足できるものではなかった。また、研磨性向上の目的で添加される水溶解性の塩類もシリカ砥粒の分散性の観点からは好ましくないものであった。シリカ砥粒の分散性が不十分な場合、仕上げ研磨後のウェーハ表面の表面粗さが大きくなり、さらにはスクラッチ傷が発生するなどの問題が起こり易くなる傾向がある。
　また、特許文献２では、ポリアクリルアミド誘導体の具体例として実施例においてＮ，Ｎ－ジメチルアクリルアミドの単独重合体が開示されるのみであるが、研磨砥粒の分散性が十分ではないものであった。このため、仕上げ研磨後のウェーハ表面の平滑性が不十分であったり、スクラッチ傷が発生する等の問題が生じ易くなる。
　特許文献３に記載のセルロース誘導体又はポリビニルアルコールも同様にウェーハ表面に対する吸着性は十分なものではなかった。加えて、特許文献２の実施例では、具体的な水溶性高分子化合物としてヒドロキシエチルセルロースを用いた実験例が開示されているが、天然物由来の化合物であるために品質のばらつきが大きいという問題もあった。 However, in the invention described in Patent Document 1, the water-soluble polymer compound used is not sufficiently adsorbed to the wafer surface, and the haze and COP of the wafer surface after finish polishing are not satisfactory. Further, water-soluble salts added for the purpose of improving the polishing properties are also not preferable from the viewpoint of dispersibility of the silica abrasive grains. If the dispersibility of the silica abrasive grains is insufficient, the surface roughness of the wafer surface after finish polishing tends to increase, and problems such as scratches tend to occur.
Patent Document 2 discloses only a homopolymer of N, N-dimethylacrylamide in the examples as specific examples of the polyacrylamide derivative, but the dispersibility of the abrasive grains is not sufficient. . For this reason, problems such as insufficient smoothness of the wafer surface after finish polishing and scratches are likely to occur.
Similarly, the cellulose derivative or polyvinyl alcohol described in Patent Document 3 is not sufficiently adsorbable on the wafer surface. In addition, in the Example of Patent Document 2, an experimental example using hydroxyethyl cellulose as a specific water-soluble polymer compound is disclosed, but since it is a compound derived from a natural product, there is a problem in that quality variation is large. There was also.
　本発明は、このような事情に鑑みてなされたものであり、シリコンウェーハの表面研磨において、ウェーハ表面を高精度に平滑化し、ＣＯＰの抑制に有効な半導体用濡れ剤及び研磨用組成物を提供することを課題とするものである。 The present invention has been made in view of such circumstances, and provides a wetting agent for semiconductor and a polishing composition effective in smoothing the wafer surface with high accuracy and effective in suppressing COP in surface polishing of a silicon wafer. It is an object to do.
　上記課題を解決するために鋭意検討した結果、本発明者らは、Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位を主体とし、実質的にカチオン性基を有さない水溶性高分子を含む半導体用濡れ剤を用いることにより、研磨後のウェーハ表面の平滑化及びＣＯＰ抑制に効果を奏することを見出し、本発明を完成するに至った。 As a result of intensive studies to solve the above-mentioned problems, the present inventors include a water-soluble polymer mainly composed of a structural unit derived from N- (meth) acryloylmorpholine and having substantially no cationic group. It has been found that the use of a wetting agent for semiconductors has an effect on smoothing the wafer surface after polishing and suppressing COP, and the present invention has been completed.
　本発明は以下の通りである。
〔１〕Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位を５０～１００ｍｏｌ％有し、実質的にカチオン性基を含まない水溶性高分子を含有する半導体用濡れ剤。
〔２〕前記Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位が１００ｍｏｌ％である前記〔１〕に記載の半導体用濡れ剤。
〔３〕前記水溶性高分子の数平均分子量が、１，０００～３００，０００の範囲であることを特徴とする前記〔１〕又は〔２〕に記載の半導体用濡れ剤。
〔４〕前記〔１〕～〔３〕のいずれかに記載の水溶性高分子の製造方法であって、重合開始剤としてノニオン性及び／又はアニオン性の重合開始剤を使用し、Ｎ－（メタ）アクリロイルモルホリン５０～１００ｍｏｌ％およびその他の単量体０～５０ｍｏｌ％をラジカル重合することを特徴とする水溶性重合体の製造方法。
〔５〕前記〔１〕～〔３〕のいずれかに記載の半導体用濡れ剤、水、砥粒及びアルカリ化合物を含んでなることを特徴とする研磨用組成物。
〔６〕Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位を５０～１００ｍｏｌ％有し、実質的にカチオン性基を含まない水溶性高分子を用いて、シリコンウェーハを研磨する方法。 The present invention is as follows.
[1] A semiconductor wetting agent containing a water-soluble polymer having 50 to 100 mol% of a structural unit derived from N- (meth) acryloylmorpholine and substantially free of a cationic group.
[2] The semiconductor wetting agent according to [1], wherein the structural unit derived from N- (meth) acryloylmorpholine is 100 mol%.
[3] The semiconductor wetting agent as described in [1] or [2] above, wherein the water-soluble polymer has a number average molecular weight in the range of 1,000 to 300,000.
[4] The method for producing a water-soluble polymer according to any one of [1] to [3], wherein a nonionic and / or anionic polymerization initiator is used as a polymerization initiator, and N— ( A method for producing a water-soluble polymer, comprising radically polymerizing 50 to 100 mol% of (meth) acryloylmorpholine and 0 to 50 mol% of another monomer.
[5] A polishing composition comprising the semiconductor wetting agent according to any one of [1] to [3], water, abrasive grains, and an alkali compound.
[6] A method of polishing a silicon wafer using a water-soluble polymer having 50 to 100 mol% of structural units derived from N- (meth) acryloylmorpholine and substantially free of a cationic group.
　本発明の半導体用濡れ剤は、研磨後のウェーハ表面への吸着性に優れるものである。このため、該半導体用濡れ剤を含む研磨用組成物を用いることにより、研磨後のウェーハ表面の平滑性を高め、かつ、耐エッチング性に優れることからＣＯＰを抑制することが可能となる。さらに、シリカの分散性も良好であることから、凝集したシリカ砥粒による擦傷や表面荒れも少なく、無傷性に優れたウェーハ表面を得ることができる。 The semiconductor wetting agent of the present invention has excellent adsorptivity to the wafer surface after polishing. For this reason, by using the polishing composition containing the semiconductor wetting agent, it is possible to increase the smoothness of the polished wafer surface and to suppress the COP because of excellent etching resistance. Furthermore, since the dispersibility of silica is also good, there are few scratches and surface roughness due to the agglomerated silica abrasive grains, and a wafer surface with excellent scratch resistance can be obtained.
　以下、本開示の代表的かつ非限定的な具体例について、詳細に説明する。この詳細な説明は、本発明の好ましい例を実施するための詳細を当業者に示すことを単純に意図しており、本開示の範囲を限定することを意図したものではない。また、以下に開示される追加的な特徴ならびに発明は、さらに改善された半導体用濡れ剤及び研磨用組成物を提供するために、他の特徴や発明とは別に、又は共に用いることができる。 Hereinafter, representative and non-limiting specific examples of the present disclosure will be described in detail. This detailed description is intended merely to provide those skilled in the art with details for practicing the preferred embodiments of the present invention and is not intended to limit the scope of the present disclosure. Also, the additional features and inventions disclosed below can be used separately from or together with other features and inventions to provide further improved semiconductor wetting agents and polishing compositions.
　また、以下の詳細な説明で開示される特徴や工程の組み合わせは、最も広い意味において本開示を実施する際に必須のものではなく、特に本開示の代表的な具体例を説明するためにのみ記載されるものである。さらに、上記及び下記の代表的な具体例の様々な特徴、ならびに、独立及び従属クレームに記載されるものの様々な特徴は、本開示の追加的かつ有用な実施形態を提供するにあたって、ここに記載される具体例のとおりに、あるいは列挙された順番のとおりに組合せなければならないものではない。 Further, the combinations of features and steps disclosed in the following detailed description are not essential in carrying out the present disclosure in the broadest sense, and are particularly only for explaining representative specific examples of the present disclosure. It is described. Moreover, various features of the representative embodiments described above and below, as well as those described in the independent and dependent claims, are described herein in providing additional and useful embodiments of the present disclosure. They do not have to be combined in the specific examples given or in the order listed.
　本明細書及び／又はクレームに記載された全ての特徴は、実施例及び／又はクレームに記載された特徴の構成とは別に、出願当初の開示ならびにクレームされた特定事項に対する限定として、個別に、かつ互いに独立して開示されることを意図するものである。さらに、全ての数値範囲及びグループ又は集団に関する記載は、出願当初の開示ならびにクレームされた特定事項に対する限定として、それらの中間の構成を開示する意図を持ってなされている。 All features described in this specification and / or claims, apart from the configuration of the features described in the examples and / or claims, are individually disclosed as limitations on the original disclosure and claimed specific matters. And are intended to be disclosed independently of each other. Further, all numerical ranges and group or group descriptions are intended to disclose intermediate configurations thereof as a limitation to the original disclosure and claimed subject matter.
　以下、本発明を詳しく説明する。尚、本明細書において、「（メタ）アクリル」とは、アクリル及びメタクリルを意味し、「（メタ）アクリレート」とは、アクリレート及びメタクリレートを意味する。また、「（メタ）アクリロイル基」とは、アクリロイル基及びメタクリロイル基を意味する。 Hereinafter, the present invention will be described in detail. In the present specification, “(meth) acryl” means acryl and methacryl, and “(meth) acrylate” means acrylate and methacrylate. The “(meth) acryloyl group” means an acryloyl group and a methacryloyl group.
＜水溶性高分子＞
　本発明の半導体用濡れ剤は、Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位を５０～１００ｍｏｌ％有し、実質的にカチオン性基を含まない水溶性高分子を含有する。Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位は、７０～１００ｍｏｌ％の範囲であることが好ましく、９０～１００ｍｏｌ％の範囲であることがより好ましく、１００ｍｏｌ％が最も好ましい。
　Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位は、ウェーハ表面への吸着性が良好であり、かつ、耐加水分解性にも優れる。このため、前記構造単位を主体とする水溶性高分子を含有する半導体用濡れ剤は、アルカリ化合物等とともに研磨用組成物を形成した場合にも優れた耐アルカリ性を示し、また、当該研磨用組成物は良好な耐エッチング性を発揮する。 <Water-soluble polymer>
The wetting agent for semiconductors of the present invention contains a water-soluble polymer having 50 to 100 mol% of structural units derived from N- (meth) acryloylmorpholine and substantially free of a cationic group. The structural unit derived from N- (meth) acryloylmorpholine is preferably in the range of 70 to 100 mol%, more preferably in the range of 90 to 100 mol%, and most preferably 100 mol%.
The structural unit derived from N- (meth) acryloylmorpholine has good adsorptivity to the wafer surface and excellent hydrolysis resistance. Therefore, the wetting agent for semiconductors containing a water-soluble polymer mainly composed of the structural unit exhibits excellent alkali resistance even when a polishing composition is formed with an alkali compound or the like, and the polishing composition The object exhibits good etching resistance.
　本発明では、Ｎ－（メタ）アクリロイルモルホリン以外に、これと共重合可能なその他の単量体を用いても良い。その他の単量体は特に限定されるものではないが、例えば、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸ブチル及び（メタ）アクリル酸２－エチルヘキシル等の（メタ）アクリル酸アルキルエステル類；（メタ）アクリル酸、クロトン酸、マレイン酸、イタコン酸及びフマル酸等の不飽和酸並びにこれらのアルキルエステル類；無水マレイン酸等の不飽和酸無水物；２－アクリルアミド－２－メチルプロパンスルホン酸及びその塩類等のスルホン酸基含有単量体；メチル（メタ）アクリルアミド、エチル（メタ）アクリルアミド、ｎ－プロピル（メタ）アクリルアミド、イソプロピル（メタ）アクリルアミド、ｎ－ブチル（メタ）アクリルアミド及び２－エチルヘキシル（メタ）アクリルアミド等のＮ－アルキル（メタ）アクリルアミド；メチルアミノプロピル（メタ）アクリルアミド、ジメチルアミノプロピル（メタ）アクリルアミド、エチルアミノプロピル（メタ）アクリルアミド及びジエチルアミノプロピル（メタ）アクリルアミド等の（ジ）アルキルアミノアルキルアミド類；メチルアミノエチル（メタ）アクリレート、ジメチルアミノエチル（メタ）アクリレート、エチルアミノエチル（メタ）アクリレート及びジエチルアミノエチル（メタ）アクリレート等の（ジ）アルキルアミノアルキル（メタ）アクリレート類；スチレン、ビニルトルエン及びビニルキシレン等の芳香族ビニル化合物；メチルビニルエーテル、エチルビニルエーテル、ｎ－プロピルビニルエーテル、イソプロピルビニルエーテル、ｎ－ブチルビニルエーテル、イソブチルビニルエーテル、ｔ－ブチルビニルエーテル、ｎ－ヘキシルビニルエーテル、２－エチルヘキシルビニルエーテル、ｎ－オクチルビニルエーテル、ｎ－ノニルビニルエーテル及びｎ－デシルビニルエーテル等の炭素数１～１０のアルキル基を有するアルキルビニルエーテル類；ギ酸ビニル、酢酸ビニル、プロピオン酸ビニル、バレリン酸ビニル、カプリン酸ビニル、ラウリン酸ビニル、ステアリン酸ビニル、安息香酸ビニル、ピパリン酸ビニル及びバーサチック酸ビニル等のビニルエステル化合物；エチレン、プロピレン、ブチレン等のα―オレフィン類等が挙げられ、これらの内の１種又は２種以上を用いることができる。
　水溶性高分子におけるこれらの単量体の使用量は、０～５０ｍｏｌ％の範囲であり、０～３０ｍｏｌ％の範囲が好ましく、０～１０ｍｏｌ％の範囲がより好ましい。その他の単量体の使用量が５０ｍｏｌ％を超えると、前記Ｎ－（メタ）アクリロイルモルホリンの使用量が５０ｍｏｌ％未満となるため、ウェーハへの吸着性が十分でなく、本発明の半導体用濡れ剤の効果が得られない場合がある。 In the present invention, in addition to N- (meth) acryloylmorpholine, other monomers copolymerizable therewith may be used. Other monomers are not particularly limited. For example, (meth) methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate (meth) ) Acrylic acid alkyl esters; Unsaturated acids such as (meth) acrylic acid, crotonic acid, maleic acid, itaconic acid and fumaric acid and their alkyl esters; Unsaturated acid anhydrides such as maleic anhydride; 2-acrylamide -Sulphonic acid group-containing monomers such as 2-methylpropanesulfonic acid and salts thereof; methyl (meth) acrylamide, ethyl (meth) acrylamide, n-propyl (meth) acrylamide, isopropyl (meth) acrylamide, n-butyl ( N-Al such as (meth) acrylamide and 2-ethylhexyl (meth) acrylamide (Di) alkylaminoalkylamides such as methyl (amino) amide; methylaminopropyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, ethylaminopropyl (meth) acrylamide and diethylaminopropyl (meth) acrylamide; (Di) alkylaminoalkyl (meth) acrylates such as (meth) acrylate, dimethylaminoethyl (meth) acrylate, ethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; styrene, vinyltoluene and vinylxylene Aromatic vinyl compounds; methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, iso Alkyl vinyl ethers having an alkyl group having 1 to 10 carbon atoms such as til vinyl ether, t-butyl vinyl ether, n-hexyl vinyl ether, 2-ethylhexyl vinyl ether, n-octyl vinyl ether, n-nonyl vinyl ether and n-decyl vinyl ether; vinyl formate , Vinyl ester compounds such as vinyl acetate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl benzoate, vinyl piperate and vinyl versatate; α- such as ethylene, propylene and butylene Examples thereof include olefins, and one or more of these can be used.
The amount of these monomers used in the water-soluble polymer ranges from 0 to 50 mol%, preferably from 0 to 30 mol%, more preferably from 0 to 10 mol%. When the amount of other monomers used exceeds 50 mol%, the amount of N- (meth) acryloylmorpholine used is less than 50 mol%, so that the adsorptivity to the wafer is not sufficient, and the semiconductor wetting of the present invention The effect of the agent may not be obtained.
　本発明の水溶性高分子は、実質的にカチオン性基を含まないものである。カチオン性基は４級アンモニウム塩基等のカチオン性基を有する単量体又は開始剤等により導入されるため、本発明において「実質的にカチオン性基を含まない」とは、これらの成分を原料として使用していないことを意味する。 The water-soluble polymer of the present invention is substantially free of a cationic group. Since the cationic group is introduced by a monomer having a cationic group such as a quaternary ammonium base, an initiator, or the like, in the present invention, “substantially does not contain a cationic group” means that these components are raw materials. Means not using as.
　水溶性高分子の数平均分子量（Ｍｎ）は、１，０００～３００，０００の範囲であることが好ましく、より好ましくは１，５００～１５０，０００の範囲であり、さらに好ましくは２，０００～１００，０００の範囲である。数平均分子量（Ｍｎ）が１，０００以上であれば、ウェーハの濡れ性が十分確保され、３００，０００以下であれば、研磨砥粒の分散性を確保することができる。なお、数平均分子量は、ＧＰＣ（ゲルパーミエーションクロマトグラフィー、例えば、ＨＬＣ－８２２０、東ソー製）を用いて、ポリスチレン換算により測定できる。 The number average molecular weight (Mn) of the water-soluble polymer is preferably in the range of 1,000 to 300,000, more preferably in the range of 1,500 to 150,000, still more preferably 2,000 to The range is 100,000. If the number average molecular weight (Mn) is 1,000 or more, the wettability of the wafer is sufficiently secured, and if it is 300,000 or less, the dispersibility of the abrasive grains can be secured. The number average molecular weight can be measured in terms of polystyrene using GPC (gel permeation chromatography, for example, HLC-8220, manufactured by Tosoh Corporation).
　また、水溶性高分子の分子量分布（ＰＤＩ）は狭い方が好ましい。具体的には、重量平均分子量（Ｍｗ）を数平均分子量（Ｍｎ）で除した値が４．０以下であることが好ましく、３．５以下であることがより好ましく、３．０以下であることがさらに好ましい。分子量分布（ＰＤＩ）が４．０以下であれば、十分な濡れ性を示し、かつ、高分子量体に起因する（シリカ）砥粒の分散性悪化も回避することができる。 Further, it is preferable that the molecular weight distribution (PDI) of the water-soluble polymer is narrow. Specifically, the value obtained by dividing the weight average molecular weight (Mw) by the number average molecular weight (Mn) is preferably 4.0 or less, more preferably 3.5 or less, and 3.0 or less. More preferably. When the molecular weight distribution (PDI) is 4.0 or less, sufficient wettability is exhibited, and deterioration in dispersibility of (silica) abrasive grains caused by a high molecular weight body can be avoided.
＜水溶性高分子の製造方法＞
　本発明における水溶性高分子は、重合溶媒中、重合開始剤としてノニオン性及び／又はアニオン性の重合開始剤を使用し、Ｎ－（メタ）アクリロイルモルホリン５０～１００ｍｏｌ％及びその他の単量体０～５０ｍｏｌ％をラジカル重合することにより得ることができる。 <Method for producing water-soluble polymer>
The water-soluble polymer in the present invention uses a nonionic and / or anionic polymerization initiator as a polymerization initiator in a polymerization solvent, N- (meth) acryloylmorpholine 50 to 100 mol%, and other monomers 0 It can be obtained by radical polymerization of ˜50 mol%.
　重合方法は特に制限されるものではないが、水溶性高分子を均一な状態で得ることができる点で、溶液重合法が好ましい。溶液重合の際の重合溶媒は、水、又は、水及び有機溶剤からなる混合溶媒を用いることができる。前記有機溶剤としては、具体的には、メタノール、エタノール、イソプロパノール、アセトン及びメチルエチルケトン等が挙げられ、これらの内の１種、又は２種以上を併用して用いてもよい。上記の内でも、水を重合溶媒とする水溶液重合法を採用することが好ましい。 The polymerization method is not particularly limited, but the solution polymerization method is preferable because a water-soluble polymer can be obtained in a uniform state. As the polymerization solvent in the solution polymerization, water or a mixed solvent composed of water and an organic solvent can be used. Specific examples of the organic solvent include methanol, ethanol, isopropanol, acetone, and methyl ethyl ketone, and one or more of these may be used in combination. Among the above, it is preferable to employ an aqueous solution polymerization method using water as a polymerization solvent.
　また、重合の際にはノニオン性及び／又はアニオン性の重合開始剤であれば公知のものを使用することができるが、特にラジカル重合開始剤が好ましく用いられる。
　ラジカル重合開始剤としては、例えば、過硫酸ナトリウム、過硫酸カリウム及び過硫酸アンモニウム等の過硫酸塩類、ｔ－ブチルハイドロパーオキサイド等のハイドロパーオキサイド類、過酸化水素等の水溶性過酸化物、メチルエチルケトンパーオキサイド、シクロヘキサノンパーオキサイド等のケトンパーオキサイド類、ジ－ｔ－ブチルパーオキサイド、ｔ－ブチルクミルパーオキサイド等のジアルキルパーオキサイド類、ｔ－ブチルパーオキシピバレート、ｔ－ヘキシルパーオキシピバレート等のパーオキシエステル類等の油溶性の過酸化物、２，２’－アゾビス［Ｎ－（２－カルボキシエチル）－２－メチルプロピオンアミジン］水和物、２，２’－アゾビス［２－（２－イミダゾリン－２－イル）プロパン］、２，２’－アゾビス［２－メチル－Ｎ－（２－ヒドロキシエチル）プロピオンアミド］及び４，４’－アゾビス－４－シアノ吉草酸等の水溶性アゾ化合物、２，２’－アゾビスイソブチロニトリル、２，２’－アゾビス（２，４－ジメチルバレロニトリル）、２，２’－アゾビス（２－メチルブチロニトリル）等の油溶性アゾ化合物等が挙げられる。
　前記ラジカル重合開始剤は１種類のみ使用しても又は２種以上を併用してもよい。
　前記ラジカル重合開始剤の中でも、重合反応の制御が行い易い点から過硫酸塩類や水溶性アゾ化合物が好ましく、特に好ましくは水溶性アゾ化合物である。
　ラジカル重合開始剤の使用割合は特に制限されないが、水溶性高分子全体を構成する全単量体の合計重量に基づいて、０．１～１０質量％の割合で使用することが好ましく、０．１～５質量％の割合がより好ましく、０．２～３質量％の割合がさらに好ましい。 In the polymerization, any known nonionic and / or anionic polymerization initiator may be used, and a radical polymerization initiator is particularly preferably used.
Examples of the radical polymerization initiator include persulfates such as sodium persulfate, potassium persulfate and ammonium persulfate, hydroperoxides such as t-butyl hydroperoxide, water-soluble peroxides such as hydrogen peroxide, methyl ethyl ketone, and the like. Ketone peroxides such as peroxide and cyclohexanone peroxide, dialkyl peroxides such as di-t-butyl peroxide and t-butylcumyl peroxide, t-butyl peroxypivalate, t-hexyl peroxypivalate, etc. Oil-soluble peroxides such as peroxyesters, 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate, 2,2′-azobis [2- ( 2-Imidazolin-2-yl) propane], 2,2′-azobis [2- Water-soluble azo compounds such as til-N- (2-hydroxyethyl) propionamide] and 4,4′-azobis-4-cyanovaleric acid, 2,2′-azobisisobutyronitrile, 2,2′- Examples thereof include oil-soluble azo compounds such as azobis (2,4-dimethylvaleronitrile) and 2,2′-azobis (2-methylbutyronitrile).
The radical polymerization initiator may be used alone or in combination of two or more.
Among the radical polymerization initiators, persulfates and water-soluble azo compounds are preferable, and water-soluble azo compounds are particularly preferable because the polymerization reaction can be easily controlled.
The ratio of the radical polymerization initiator used is not particularly limited, but is preferably 0.1 to 10% by mass based on the total weight of all monomers constituting the entire water-soluble polymer. A ratio of 1 to 5% by mass is more preferable, and a ratio of 0.2 to 3% by mass is more preferable.
　水溶性重合体の重合は、必要に応じて連鎖移動剤の存在下で実施しても良い。連鎖移動剤を使用することにより、水溶性高分子の分子量を適度に調整することができる。
　連鎖移動剤は公知のものを使用することができ、具体的には、エタンチオール、１－プロパンチオール、２－プロパンチオール、１－ブタンチオール、２－ブタンチオール、１－ヘキサンチオール、２－ヘキサンチオール、２－メチルヘプタン－２－チオール、２－ブチルブタン－１－チオール、１，１－ジメチル－１－ペンタンチオール、１－オクタンチオール、２－オクタンチオール、１－デカンチオール、３－デカンチオール、１－ウンデカンチオール、１－ドデカンチオール、２－ドデカンチオール、１－トリデカンチオール、１－テトラデカンチオール、３－メチル－３－ウンデカンチオール、５－エチル－５－デカンチオール、ｔｅｒｔ－テトラデカンチオール、１－ヘキサデカンチオール、１－ヘプタデカンチオール及び１－オクタデカンチオール等の炭素数２～２０のアルキル基を有するアルキルチオール化合物の他、メルカプト酢酸、メルカプトプロピオン酸、２－メルカプトエタノール等が挙げられ、これらの内の１種又は２種以上を用いることができる。 The polymerization of the water-soluble polymer may be carried out in the presence of a chain transfer agent as necessary. By using a chain transfer agent, the molecular weight of the water-soluble polymer can be appropriately adjusted.
As the chain transfer agent, known ones can be used. Specifically, ethanethiol, 1-propanethiol, 2-propanethiol, 1-butanethiol, 2-butanethiol, 1-hexanethiol, 2-hexane Thiol, 2-methylheptane-2-thiol, 2-butylbutane-1-thiol, 1,1-dimethyl-1-pentanethiol, 1-octanethiol, 2-octanethiol, 1-decanethiol, 3-decanethiol, 1-undecanethiol, 1-dodecanethiol, 2-dodecanethiol, 1-tridecanethiol, 1-tetradecanethiol, 3-methyl-3-undecanethiol, 5-ethyl-5-decanethiol, tert-tetradecanethiol, 1 -Hexadecanethiol, 1-heptadecanethiol and 1- In addition to alkylthiol compounds having an alkyl group of 2 to 20 carbon atoms such as kutadecanethiol, mercaptoacetic acid, mercaptopropionic acid, 2-mercaptoethanol, etc. may be mentioned, and one or more of these should be used Can do.
　連鎖移動剤の中でも、ウェーハへの吸着性が良好となる点から炭素数２～２０のアルキル基を有するアルキルチオール化合物が好ましく、炭素数４～２０のアルキル基を有するものがより好ましく、炭素数６～２０のアルキル基を有するものがさらに好ましい。
　連鎖移動剤を用いる際、その好ましい使用量は、全単量体の量に対して０．１～１０質量％であり、さらに好ましくは０．５～５質量％である。 Among chain transfer agents, an alkylthiol compound having an alkyl group having 2 to 20 carbon atoms is preferable from the viewpoint of good adsorbability to a wafer, more preferably one having an alkyl group having 4 to 20 carbon atoms, More preferred are those having 6 to 20 alkyl groups.
When a chain transfer agent is used, the preferred amount is 0.1 to 10% by weight, more preferably 0.5 to 5% by weight, based on the amount of all monomers.
　重合時における反応温度としては、３０～１００℃が好ましく、４０～９０℃がより好ましく、５０～８０℃がさらに好ましい。 The reaction temperature during polymerization is preferably 30 to 100 ° C, more preferably 40 to 90 ° C, and further preferably 50 to 80 ° C.
＜半導体用濡れ剤＞
　本発明の半導体用濡れ剤は、前記水溶性高分子及び水を含んでなる。水は、濡れ剤としての効果を損なわないよう、純度の高いものを用いることが好ましい。具体的には、イオン交換樹脂により不純物イオンを除去した後、濾過により異物を除去した純水若しくは超純水、又は、蒸留水を使用することが好ましい。濡れ剤には、この他に、水との混和性が高いアルコール及びケトン類等の有機溶剤等を含んでいてもよい。
　半導体用濡れ剤中の水溶性高分子の割合は、水溶液として扱いやすい粘度であれば特に限定されないが、１～５０質量％の範囲が好ましく、３～４０質量％の範囲がより好ましく、５～３０質量％の範囲がさらに好ましい。 <Wetting agent for semiconductors>
The semiconductor wetting agent of the present invention comprises the water-soluble polymer and water. It is preferable to use high-purity water so as not to impair the effect as a wetting agent. Specifically, it is preferable to use pure water, ultrapure water, or distilled water from which foreign ions are removed by filtration after removing impurity ions with an ion exchange resin. In addition to this, the wetting agent may contain an organic solvent such as alcohol and ketone having high miscibility with water.
The ratio of the water-soluble polymer in the wetting agent for semiconductor is not particularly limited as long as it is a viscosity that can be easily handled as an aqueous solution, but is preferably in the range of 1 to 50% by mass, more preferably in the range of 3 to 40% by mass. The range of 30% by mass is more preferable.
　本発明における水溶性高分子は、ウェーハ表面等への吸着性に優れ、特に完全に酸化膜が除去された状態のウェーハ表面に対して高い吸着性を示す。このため、ウェーハの表面処理工程に本発明の半導体用濡れ剤を用いた場合、研磨後のウェーハ表面の平滑性を高め、ＣＯＰ及びパーティクル付着による汚染等を低減することができる。これらの効果が得られる理由として、以下のメカニズムを想定している。
　ウェーハ表面の平滑性に関しては、半導体用濡れ剤中の水溶性高分子がウェーハ表面に吸着することで、ＣＭＰのメカニカル研磨においてウェーハ表面と砥粒との間の摩擦が緩和される。このため、メカニカル研磨によりウェーハ表面に形成される微小な凹凸が低減され、平滑性が向上すると考えられる。 The water-soluble polymer in the present invention is excellent in adsorptivity to the wafer surface and the like, and particularly exhibits high adsorptivity to the wafer surface in a state where the oxide film is completely removed. For this reason, when the semiconductor wetting agent of the present invention is used in the wafer surface treatment process, the smoothness of the polished wafer surface can be improved, and contamination caused by COP and particle adhesion can be reduced. The following mechanism is assumed as a reason why these effects can be obtained.
Regarding the smoothness of the wafer surface, the water-soluble polymer in the semiconductor wetting agent is adsorbed on the wafer surface, so that the friction between the wafer surface and the abrasive grains is reduced in the mechanical polishing of CMP. For this reason, it is considered that the minute unevenness formed on the wafer surface by mechanical polishing is reduced and the smoothness is improved.
　また、上述した通り、メカニカル研磨では、ウェーハ表面に研磨用組成物が供給されるとともに研磨パッドがウェーハ表面に押し付けられて回転することにより、ウェーハ表面を物理的に研磨する。よって、ウェーハ表面ではＣＯＰ以外の箇所に研磨パッドが押し付けられ、ウェーハ表面に対して垂直方向に研磨されることとなる。メカニカル研磨の進行に伴いＣＯＰは次第に小さくなり、その深さ以上にウェーハ表面が研磨されたときにＣＯＰは消滅することとなる。したがって、メカニカル研磨は、ＣＯＰの数を減少させ、又その大きさを低減する効果を示すと考えられる。
　一方、ケミカル研磨では、研磨の際にＣＯＰ内に研磨用組成物が入り込み、塩基性化合物がＣＯＰ内部を腐食又はエッチングする。このように、ＣＯＰ内部では、その内部壁に対して垂直方向に研磨されるため、ケミカル研磨の進行に伴いウェーハ表面のＣＯＰは大きくなると考えられる。
　本発明では、ウェーハ表面に吸着した水溶性高分子は、メカニカル研磨以上にケミカル研磨を抑制する働きを有するものと想定している。ウェーハに対する水溶性高分子の吸着性が高いほどこの傾向は強くなり、結果として平滑性が高くＣＯＰの少ないウェーハ表面を得ることができると推察される。 In addition, as described above, in mechanical polishing, the polishing composition is supplied to the wafer surface and the polishing pad is pressed against the wafer surface and rotated to physically polish the wafer surface. Therefore, the polishing pad is pressed against a portion other than the COP on the wafer surface and polished in a direction perpendicular to the wafer surface. As the mechanical polishing proceeds, the COP gradually decreases, and the COP disappears when the wafer surface is polished beyond the depth. Therefore, it is considered that the mechanical polishing shows the effect of reducing the number of COPs and the size thereof.
On the other hand, in chemical polishing, the polishing composition enters the COP during polishing, and the basic compound corrodes or etches the inside of the COP. As described above, since the polishing is performed in the direction perpendicular to the inner wall of the COP, it is considered that the COP on the wafer surface increases with the progress of chemical polishing.
In the present invention, it is assumed that the water-soluble polymer adsorbed on the wafer surface has a function of suppressing chemical polishing more than mechanical polishing. It is presumed that this tendency becomes stronger as the water-soluble polymer adsorbability to the wafer becomes higher, and as a result, a wafer surface having high smoothness and low COP can be obtained.
　さらに、ウェーハ表面に水溶性高分子が吸着することにより、その表面が親水化される。これにより、研磨の際のパーティクルの付着による汚染も防止することができる。 Furthermore, when the water-soluble polymer is adsorbed on the wafer surface, the surface is hydrophilized. Thereby, contamination due to adhesion of particles during polishing can also be prevented.
　なお、本発明によれば、こうした水溶性高分子をウェーハに対して吸着させてウェーハを研磨する方法も提供される。水溶性高分子をウェーハに対して吸着させる形態としては、水溶性高分子と水とを含む半導体用濡れ剤として供給するほか、本開示の水溶性高分子、水、砥粒及びアルカリ化合物を含む研磨用組成物をウェーハに対して供給する形態が含まれる。 The present invention also provides a method for polishing a wafer by adsorbing such a water-soluble polymer to the wafer. As a form in which the water-soluble polymer is adsorbed to the wafer, the water-soluble polymer is supplied as a semiconductor wetting agent containing water-soluble polymer and water, and includes the water-soluble polymer of the present disclosure, water, abrasive grains, and an alkali compound The form which supplies polishing composition with respect to a wafer is contained.
＜研磨用組成物＞
　本発明の研磨用組成物は、上記半導体用濡れ剤、水、砥粒及びアルカリ化合物を含んでなるものである。研磨用組成物中の半導体用濡れ剤の割合は、特に限定されるものではないが、研磨用組成物がＣＭＰにおける扱い上、又ウェーハ表面に吸着するにあたり適度な粘度とすることが好ましい。研磨用組成物の具体的な粘度は、０．１～１０ｍＰａ・ｓの範囲であることが好ましく、０．３～８ｍＰａ・ｓの範囲であることがより好ましく、０．５～５ｍＰａ・ｓの範囲であることがさらに好ましい。
　また、上記水溶性高分子は、研磨剤用組成物全体の０．００１～１０質量％の範囲となるよう用いることが好ましく、０．００５～５質量％の範囲であることがより好ましい。 <Polishing composition>
The polishing composition of the present invention comprises the semiconductor wetting agent, water, abrasive grains, and an alkali compound. The ratio of the semiconductor wetting agent in the polishing composition is not particularly limited, but it is preferable that the polishing composition has an appropriate viscosity for handling in CMP and adsorbing to the wafer surface. The specific viscosity of the polishing composition is preferably in the range of 0.1 to 10 mPa · s, more preferably in the range of 0.3 to 8 mPa · s, and 0.5 to 5 mPa · s. More preferably, it is in the range.
The water-soluble polymer is preferably used in a range of 0.001 to 10% by mass, more preferably in a range of 0.005 to 5% by mass with respect to the entire abrasive composition.
　砥粒としてはコロイダルシリカ等を用いることができる。砥粒としてコロイダルシリカを用いる場合、研磨用組成物におけるその含有量は、０．１～５０質量％であることが好ましく、１～３０質量％であることがより好ましく、３～２０質量％であることがさらに好ましい。コロイダルシリカの使用量が０．１質量％以上であればメカニカル研磨の研磨速度が良好なものとなる。また、５０質量％以下であれば、砥粒の分散性が保持され、ウェーハ表面の平滑性が良好なものとすることができる。 Colloidal silica or the like can be used as the abrasive grains. When colloidal silica is used as the abrasive, its content in the polishing composition is preferably 0.1 to 50% by mass, more preferably 1 to 30% by mass, and 3 to 20% by mass. More preferably it is. If the usage-amount of colloidal silica is 0.1 mass% or more, the polishing rate of mechanical polishing will become favorable. Moreover, if it is 50 mass% or less, the dispersibility of an abrasive grain is hold | maintained and the smoothness of a wafer surface can be made favorable.
　コリダルシリカの平均粒子径は、必要とする研磨速度と研磨後のウェーハ表面の平滑性から適宜選択されるが、一般的には、２～５００ｎｍの範囲であり、５～３００ｎｍの範囲が好ましく、５～２００ｎｍの範囲がより好ましい。 The average particle size of the corridal silica is appropriately selected from the required polishing rate and the smoothness of the polished wafer surface, but is generally in the range of 2 to 500 nm, preferably in the range of 5 to 300 nm. A range of ˜200 nm is more preferable.
　アルカリ化合物としては、水溶性のアルカリ化合物であれば特に制限はなく、アルカリ金属水酸化物、アミン類又はアンモニア若しくは４級水酸化アンモニウム塩等を使用することができる。アルカリ金属水酸化物としては、水酸化カリウム、水酸化ナトリウム、水酸化ルビジウム及び水酸化セシウム等が挙げられる。アミン類としては、トリエチルアミン、モノエタノールアミン、ジエタノールアミン、トリエタノールアミン、ジイソプロパノールアミン、エチレンジアミン、ヘキサメチレンジアミン、ジエチレントリアミン、トリエチルペンタミン及びテトラエチルペンタミン等が挙げられる。４級水酸化アンモニウム塩としては、水酸化テトラメチルアンモニウム、水酸化テトラエチルアンモニウム及び水酸化テトラブチルアンモニウム等が挙げられる。これらの内では、半導体基板に対する汚染が少ないという点からアンモニア又は４級水酸化アンモニウム塩が好ましい。
　本発明の研磨用組成物は、前記アルカリ化合物を添加することにより、そのｐＨが８～１３となるように調整されるのが好ましい。ｐＨの範囲は８．５～１２に調整するのがより好ましい。 The alkali compound is not particularly limited as long as it is a water-soluble alkali compound, and alkali metal hydroxides, amines, ammonia, quaternary ammonium hydroxide salts, and the like can be used. Examples of the alkali metal hydroxide include potassium hydroxide, sodium hydroxide, rubidium hydroxide and cesium hydroxide. Examples of amines include triethylamine, monoethanolamine, diethanolamine, triethanolamine, diisopropanolamine, ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylpentamine, and tetraethylpentamine. Examples of the quaternary ammonium hydroxide salt include tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide. Among these, ammonia or a quaternary ammonium hydroxide salt is preferable from the viewpoint of less contamination of the semiconductor substrate.
The polishing composition of the present invention is preferably adjusted to have a pH of 8 to 13 by adding the alkali compound. More preferably, the pH range is adjusted to 8.5-12.
　研磨剤用組成物には、上記以外にも、必要に応じて有機溶剤、各種キレート剤及び界面活性剤等を添加することができる。 In addition to the above, an organic solvent, various chelating agents, a surfactant, and the like can be added to the polishing agent composition as necessary.
　以下、実施例に基づいて本発明を具体的に説明する。尚、本発明は、これらの実施例により限定されるものではない。尚、以下において「部」及び「％」は、特に断らない限り質量部及び質量％を意味する。
　製造例で得られた水溶性高分子の分析方法並びに、実施例及び比較例における半導体用濡れ剤又は研磨用組成物の評価方法について以下に記載する。 Hereinafter, the present invention will be specifically described based on examples. In addition, this invention is not limited by these Examples. In the following, “parts” and “%” mean mass parts and mass% unless otherwise specified.
It describes below about the analysis method of the water-soluble polymer obtained by the manufacture example, and the evaluation method of the wetting agent for semiconductors or polishing composition in an Example and a comparative example.
＜分子量測定＞
　各製造例で得られた重合体について、ＧＰＣ（ゲルパーミエーションクロマトグラフィー　ＨＬＣ－８２２０、東ソー製）を用いて、ポリスチレン換算により重量平均分子量（Ｍｗ）及び数平均分子量（Ｍｎ）を測定した。また、得られた値から分子量分布（ＰＤＩ＝Ｍｗ／Ｍｎ）を算出した。 <Molecular weight measurement>
About the polymer obtained by each manufacture example, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured by polystyrene conversion using GPC (gel permeation chromatography HLC-8220, product made from Tosoh). Moreover, molecular weight distribution (PDI = Mw / Mn) was computed from the obtained value.
＜耐エッチング性（Ｅ．Ｒ．）＞
　ガラスカッターで３×６ｃｍに切出したウェーハの重量を測定後、３％フッ酸水溶液に２０秒浸漬してウェーハ表面の酸化膜を除去し、その後純水で１０秒洗浄した。この工程をウェーハの表面が完全撥水になるまで繰り返した。次いで、アンモニア：水の重量比が１：１９であるアンモニア水に、水溶性高分子の濃度が０．１８ｗｔ％となるように半導体用濡れ剤を加えて、エッチング薬液を調整した。ウェーハをエッチング薬液に完全に浸漬させ、２５℃、１２時間静置してエッチングした。エッチング前後のウェーハ重量変化から、次式に従いエッチングレート（Ｅ．Ｒ．）を算出した。
Figure JPOXMLDOC01-appb-M000001
 <Etching resistance (E.R.)>
After measuring the weight of the wafer cut to 3 × 6 cm with a glass cutter, it was immersed in a 3% hydrofluoric acid aqueous solution for 20 seconds to remove the oxide film on the wafer surface, and then washed with pure water for 10 seconds. This process was repeated until the wafer surface was completely water repellent. Next, an etching chemical solution was prepared by adding a semiconductor wetting agent to ammonia water having an ammonia: water weight ratio of 1:19 so that the concentration of the water-soluble polymer was 0.18 wt%. The wafer was completely immersed in an etching chemical solution and left to stand at 25 ° C. for 12 hours for etching. From the wafer weight change before and after etching, the etching rate (E.R.) was calculated according to the following formula.
Figure JPOXMLDOC01-appb-M000001
＜濡れ性＞
　耐エッチング性と同様の方法にてウェーハ表面の酸化膜を除去後、０．１８ｗｔ％の水溶性高分子溶液中に５分間浸漬した。浸漬後、ピンセットを用いて、ウェーハの表面が液面に対して垂直になるように引き上げ、１０秒経過時点におけるウェーハ端部からの撥水距離を目視で確認し、以下の基準により判定した。
　○：撥水距離　５ｍｍ未満
　△：撥水距離　５～１０ｍｍ
　×：撥水距離　１０ｍｍ超 <Wettability>
The oxide film on the wafer surface was removed by the same method as etching resistance, and then immersed in a 0.18 wt% water-soluble polymer solution for 5 minutes. After immersion, the surface of the wafer was pulled up using a tweezers so as to be perpendicular to the liquid level, and the water-repellent distance from the end of the wafer at the time when 10 seconds had passed was visually confirmed, and judged according to the following criteria.
○: Water repellent distance less than 5 mm △: Water repellent distance 5 to 10 mm
×: Water repellent distance> 10mm
＜ウェーハ外観＞
　耐エッチング性と同様の方法でエッチングを行った後の、ウェーハ表面を目視で確認し、以下の基準により判定した。
　○：表面に荒れが認められない
　△：表面がやや荒れている
　×：表面が著しく荒れている <Wafer appearance>
The wafer surface after etching was performed by the same method as the etching resistance was visually confirmed, and judged according to the following criteria.
○: No roughening on the surface △: The surface is slightly rough ×: The surface is extremely rough
＜耐アルカリ性＞
　５０ｃｃのスクリュー瓶に水酸化ナトリウムを水に溶かして調整したｐＨ１０のアルカリ水溶液４０ｇを入れた後、水溶性高分子５．０ｇを加え、蓋をして良く混合した。アルミブロックヒーター内で５０℃、１ヶ月静置後の加水分解率をＧＣ（ガスクロマトグラフィー　ＧＣ－２０１４、島津製作所製）で評価し、以下の基準より判定した。
　○：水溶性高分子の加水分解率が５％未満
　×：水溶性高分子の加水分解率が５％以上 <Alkali resistance>
A 50 cc screw bottle was charged with 40 g of an aqueous alkali solution adjusted to pH 10 by dissolving sodium hydroxide in water, 5.0 g of a water-soluble polymer was added, and the mixture was covered and mixed well. The hydrolysis rate after standing at 50 ° C. for 1 month in an aluminum block heater was evaluated by GC (Gas Chromatography GC-2014, manufactured by Shimadzu Corporation), and judged according to the following criteria.
○: Hydrolysis rate of water-soluble polymer is less than 5% ×: Hydrolysis rate of water-soluble polymer is 5% or more
＜シリカ分散性＞
　９ｃｃスクリュー瓶にコロイダルシリカ（１次粒子径：３０～５０ｎｍ）５．０ｇに樹脂固形分２０％の水溶性高分子水溶液を０．５ｇ加えて、良く混合した。一晩静置後のシリカの粒子径（Ａ）を動的光散乱法（ＥＬＳＺ－１０００、大塚電子製）により測定し、水溶性高分子を加えていないコロイダルシリカの粒子径（Ｂ）からの変化率を下式に従って算出し、以下の基準より判定した。
変化率（％）＝｛（Ａ－Ｂ）／Ｂ｝×１００
　○：変化率が１０％未満
　△：変化率が１０％以上～３０％未満
　×：変化率が３０％以上 <Silica dispersibility>
In a 9 cc screw bottle, 0.5 g of a water-soluble polymer aqueous solution having a resin solid content of 20% was added to 5.0 g of colloidal silica (primary particle size: 30 to 50 nm) and mixed well. The particle size (A) of the silica after standing overnight was measured by a dynamic light scattering method (ELSZ-1000, manufactured by Otsuka Electronics Co., Ltd.), and the particle size (B) of the colloidal silica to which no water-soluble polymer was added. The rate of change was calculated according to the following formula and judged according to the following criteria.
Rate of change (%) = {(AB) / B} × 100
○: Change rate is less than 10% △: Change rate is 10% to less than 30% ×: Change rate is 30% or more
製造例１
≪水溶性高分子の合成≫
　攪拌翼、還流冷却管、温度計、各種導入管を備えた５Ｌの４つ口フラスコを用意し、純水１０００部を仕込んだ後、窒素導入管から１０ｍｌ／ｍｉｎの流量にて窒素を吹き込みつつ、攪拌しながら４０ｍｉｎかけて内温を８０℃に昇温した。
　昇温を確認後、４，４’－アゾビス－４－シアノ吉草酸（大塚化学社製、商品名「ＡＣＶＡ」）２．８部を純水３０部に溶解した開始剤溶液を一括で加えた。５分後、Ｎ－アクリロイルモルホリン（興人社製、以下「ＡＣＭＯ」という）７００部を純水１６００部に溶解したモノマー水溶液をモノマー導入管から１時間かけて滴下し、重合を行った。また、モノマー水溶液と並行して、２－メルカプトエタノール（和光純薬工業社製）１．４部を純水１４０部に溶解した連鎖移動剤水溶液を別の導入管から１時間かけて滴下した。
　モノマー及び連鎖移動剤の各水溶液の滴下終了後、８０℃でさらに２時間重合を行った。その後、フラスコを室温まで冷却し、４－メトキシフェノールを０．３部加えて重合を停止することにより重合体１を得た。この重合体１の数平均分子量（Ｍｎ）は２４，０００であり、分子量分布（ＰＤＩ）は２．４であった。また、ＧＣから算出した重合率は１００％であった。 Production Example 1
≪Synthesis of water-soluble polymer≫
A 5 L four-necked flask equipped with a stirring blade, a reflux condenser, a thermometer, and various introduction tubes was prepared. After charging 1000 parts of pure water, nitrogen was blown from the nitrogen introduction tube at a flow rate of 10 ml / min. The internal temperature was raised to 80 ° C. over 40 min with stirring.
After confirming the temperature rise, an initiator solution prepared by dissolving 2.8 parts of 4,4′-azobis-4-cyanovaleric acid (trade name “ACVA” manufactured by Otsuka Chemical Co., Ltd.) in 30 parts of pure water was added all at once. . After 5 minutes, a monomer aqueous solution in which 700 parts of N-acryloylmorpholine (manufactured by Kojin Co., Ltd., hereinafter referred to as “ACMO”) was dissolved in 1600 parts of pure water was dropped from the monomer introduction tube over 1 hour to perform polymerization. In parallel with the monomer aqueous solution, a chain transfer agent aqueous solution in which 1.4 parts of 2-mercaptoethanol (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 140 parts of pure water was dropped from another introduction tube over 1 hour.
After completion of the dropwise addition of each aqueous solution of the monomer and the chain transfer agent, polymerization was further performed at 80 ° C. for 2 hours. Thereafter, the flask was cooled to room temperature, and 0.3 parts of 4-methoxyphenol was added to stop the polymerization, thereby obtaining a polymer 1. This polymer 1 had a number average molecular weight (Mn) of 24,000 and a molecular weight distribution (PDI) of 2.4. The polymerization rate calculated from GC was 100%.
製造例２
　製造例１において、連鎖移動剤を使用しなかった以外は同様の操作を行い、重合体２を得た。重合体２のＭｎは１２０，０００であり、ＰＤＩは３．０であった。また、重合率は９９％であった。 Production Example 2
The same operation as in Production Example 1 was carried out except that no chain transfer agent was used, and Polymer 2 was obtained. The Mn of the polymer 2 was 120,000 and the PDI was 3.0. The polymerization rate was 99%.
製造例３
　製造例２において、開始剤であるＡＣＶＡの使用量を０．５部に変更した以外は同様の操作を行い、重合体３を得た。重合体３のＭｎは２５０，０００であり、ＰＤＩは３．３であった。また、重合率は９９％であった。 Production Example 3
Polymer 3 was obtained in the same manner as in Production Example 2 except that the amount of ACVA used as the initiator was changed to 0.5 part. The Mn of the polymer 3 was 250,000 and the PDI was 3.3. The polymerization rate was 99%.
製造例４
　製造例１において、使用するモノマーをＡＣＭＯ６３０部（８２ｍｏｌ％）、アクリル酸７０部（１８ｍｏｌ％）に変更した以外は同様の操作を行い、重合体４を得た。重合体４のＭｎは２５，０００であり、ＰＤＩは２．５であった。また、重合率は９９％であった。 Production Example 4
Polymer 4 was obtained in the same manner as in Production Example 1 except that the monomers used were changed to ACMO 630 parts (82 mol%) and acrylic acid 70 parts (18 mol%). The Mn of the polymer 4 was 25,000 and the PDI was 2.5. The polymerization rate was 99%.
製造例５
　製造例１において、使用するモノマーをＡＣＭＯ５６０部（６０ｍｏｌ％）、アクリル酸１４０部（４０ｍｏｌ％）に変更した以外は同様の操作を行い、重合体５を得た。重合体５のＭｎは２５，０００であり、ＰＤＩは２．４であった。また、重合率は９９％であった。 Production Example 5
A polymer 5 was obtained in the same manner as in Production Example 1 except that the monomers used were changed to ACMO 560 parts (60 mol%) and acrylic acid 140 parts (40 mol%). The Mn of the polymer 5 was 25,000 and the PDI was 2.4. The polymerization rate was 99%.
製造例６
　製造例１において、使用した開始剤を２，２’－アゾビス［２－（２－イミダゾリン－２－イル）プロパン］二硫酸塩二水和物（和光純薬工業社製、商品名「ＶＡ－０４６Ｂ」）０．６部に変更し、重合温度を６０℃とした以外は同様の操作を行い、重合体６を得た。重合体６のＭｎは２５，０００であり、ＰＤＩは２．５であった。また、重合率は９９％であった。 Production Example 6
In Production Example 1, the initiator used was 2,2′-azobis [2- (2-imidazolin-2-yl) propane] disulfate dihydrate (manufactured by Wako Pure Chemical Industries, Ltd., trade name “VA-”). 046B ") was changed to 0.6 part, and the same operation was performed except that the polymerization temperature was changed to 60 ° C to obtain a polymer 6. The Mn of the polymer 6 was 25,000 and the PDI was 2.5. The polymerization rate was 99%.
製造例７
　製造例１において、使用するモノマーをＡＣＭＯ４２０部（４３ｍｏｌ％）、アクリル酸２８０部（５７ｍｏｌ％）に変更した以外は同様の操作を行い、重合体７を得た。重合体７のＭｎは２４，０００であり、ＰＤＩは２．４であった。また、重合率は９８％であった。 Production Example 7
Polymer 7 was obtained in the same manner as in Production Example 1, except that the monomer used was changed to 420 parts (43 mol%) of ACMO and 280 parts (57 mol%) of acrylic acid. The Mn of the polymer 7 was 24,000, and the PDI was 2.4. The polymerization rate was 98%.
製造例８
　製造例１において、使用するモノマーをＮ，Ｎ－ジメチルアクリルアミド７００部に変更した以外は同様の操作を行い、重合体８を得た。重合体８のＭｎは２２，０００であり、ＰＤＩは２．２であった。また、重合率は９９％であった。 Production Example 8
A polymer 8 was obtained in the same manner as in Production Example 1 except that the monomer used was changed to 700 parts of N, N-dimethylacrylamide. The Mn of the polymer 8 was 22,000, and the PDI was 2.2. The polymerization rate was 99%.
　製造例１～８で得られた各重合体の内容及び物性値について表１に記載した。
Figure JPOXMLDOC01-appb-T000002
 The contents and physical properties of each polymer obtained in Production Examples 1 to 8 are shown in Table 1.
Figure JPOXMLDOC01-appb-T000002
　表１に示された化合物の詳細は以下の通り。
ＡＣＭＯ：アクリロイルモルホリン
ＡＡ：アクリル酸
ＤＭＡＡ：Ｎ，Ｎ－ジメチルアクリルアミド
ＡＣＶＡ：４，４’－アゾビス－４－シアノ吉草酸（大塚化学社製）
ＶＡ－０６４Ｂ：２，２’－アゾビス［２－（２－イミダゾリン－２－イル）プロパン］二硫酸塩二水和物（和光純薬工業社製） Details of the compounds shown in Table 1 are as follows.
ACMO: acryloylmorpholine AA: acrylic acid DMAA: N, N-dimethylacrylamide ACVA: 4,4′-azobis-4-cyanovaleric acid (manufactured by Otsuka Chemical Co., Ltd.)
VA-064B: 2,2′-azobis [2- (2-imidazolin-2-yl) propane] disulfate dihydrate (manufactured by Wako Pure Chemical Industries, Ltd.)
実施例１
　水溶性高分子である重合体１の濃度が１５質量％となるように水を加え、半導体用濡れ剤を調整した。得られた半導体用濡れ剤について、耐エッチング性、濡れ性、ウェーハ外観及び耐アルカリ性の評価を行った。得られた結果について表２に示した。
　また、アンモニア水を加えてｐＨを１０．０に調整したコロイダルシリカ分散液（１次粒子系３０～５０ｎｍ、シリカ固形分１０％）１０．０ｇ、上記半導体用濡れ剤を０．１ｇ添加して、研磨剤用組成物を得た。得られた研磨剤用組成物についてシリカ分散性を評価し、表２に結果を示した。 Example 1
Water was added so that the concentration of the polymer 1 which is a water-soluble polymer was 15% by mass to prepare a semiconductor wetting agent. About the obtained wetting agent for semiconductors, etching resistance, wettability, wafer appearance and alkali resistance were evaluated. The results obtained are shown in Table 2.
Also, 10.0 g of colloidal silica dispersion (primary particle system 30-50 nm, silica solid content 10%) adjusted to pH 10.0 by adding ammonia water and 0.1 g of the above-mentioned wetting agent for semiconductor were added. A composition for an abrasive was obtained. The obtained composition for abrasives was evaluated for silica dispersibility, and Table 2 shows the results.
実施例２
　水溶性高分子として重合体２を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Example 2
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 2 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
実施例３
　水溶性高分子として重合体３を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Example 3
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 3 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
実施例４
　水溶性高分子である重合体１の濃度が１０．５質量％となるように水を加え、半導体用濡れ剤を調整した。得られた半導体用濡れ剤について、耐エッチング性、濡れ性、ウェーハ外観及び耐アルカリ性の評価を行った。得られた結果について表２に示した。
　また、前記半導体濡れ剤を用いて実施例１と同様の操作により研磨剤用組成物を得た。得られた研磨剤用組成物についてシリカ分散性を評価し、表２に結果を示した。 Example 4
Water was added so that the concentration of the polymer 1 which is a water-soluble polymer was 10.5% by mass to prepare a wetting agent for semiconductor. About the obtained wetting agent for semiconductors, etching resistance, wettability, wafer appearance and alkali resistance were evaluated. The results obtained are shown in Table 2.
Moreover, the composition for abrasive | polishing agents was obtained by operation similar to Example 1 using the said semiconductor wetting agent. The obtained composition for abrasives was evaluated for silica dispersibility, and Table 2 shows the results.
実施例５
　水溶性高分子である重合体１の濃度が４．５質量％となるように水を加え、半導体用濡れ剤を調整した。得られた半導体用濡れ剤について、耐エッチング性、濡れ性、ウェーハ外観及び耐アルカリ性の評価を行った。得られた結果について表２に示した。
　また、前記半導体濡れ剤を用いて実施例１と同様の操作により研磨剤用組成物を得た。得られた研磨剤用組成物についてシリカ分散性を評価し、表２に結果を示した。 Example 5
Water was added so that the concentration of the polymer 1 which is a water-soluble polymer was 4.5% by mass, and a semiconductor wetting agent was prepared. About the obtained wetting agent for semiconductors, etching resistance, wettability, wafer appearance and alkali resistance were evaluated. The results obtained are shown in Table 2.
Moreover, the composition for abrasive | polishing agents was obtained by operation similar to Example 1 using the said semiconductor wetting agent. The obtained composition for abrasives was evaluated for silica dispersibility, and Table 2 shows the results.
実施例６
　水溶性高分子として重合体１を５０％及び重合体２を５０％使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Example 6
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that 50% of the polymer 1 and 50% of the polymer 2 were used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
実施例７
　水溶性高分子として重合体４を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Example 7
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 4 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
実施例８
　水溶性高分子として重合体５を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Example 8
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 5 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
比較例１
　水溶性高分子として重合体６を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Comparative Example 1
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 6 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
比較例２
　水溶性高分子として重合体７を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Comparative Example 2
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 7 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
比較例３
　水溶性高分子として重合体８を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Comparative Example 3
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that the polymer 8 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
比較例４
　水溶性高分子としてヒドロキシエチルセルロース（和光純薬工業社製、重量平均分子量９０，０００）を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Comparative Example 4
A wetting agent for semiconductor and an abrasive composition were prepared in the same manner as in Example 1 except that hydroxyethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight 90,000) was used as the water-soluble polymer. went. The evaluation results obtained are shown in Table 2.
比較例５
　水溶性高分子としてＰＶＰ　Ｋ３０を使用した以外は実施例１と同様に半導体用濡れ剤及び研磨剤組成物を調製し、同様の評価を行った。得られた評価結果について表２に示した。 Comparative Example 5
A semiconductor wetting agent and an abrasive composition were prepared in the same manner as in Example 1 except that PVP K30 was used as the water-soluble polymer, and the same evaluation was performed. The evaluation results obtained are shown in Table 2.
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　表２に示された水溶性高分子の詳細は以下の通り。
ＨＥＣ：ヒドロキシエチルセルロース（和光純薬工業社製、重量平均分子量９０，０００）
ＰＶＰ　Ｋ３０：ポリビニルピロリドン（東京化成工業社製） Details of the water-soluble polymer shown in Table 2 are as follows.
HEC: hydroxyethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight 90,000)
PVP K30: Polyvinylpyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.)
　実施例１～８は、本発明で規定する水溶性高分子を用いた実験例であり、ウェーハへの吸着性が高いため、耐エッチング性、濡れ性及びウェーハへの外観に優れる結果が得られている。また、研磨剤組成物とした場合のシリカ分散性にも優れることが確認された。中でも、同程度の数平均分子量及び分子量分布を有する水溶性高分子を用いた実施例１、７及び８の結果から、Ｎ－（メタ）アクリロイルモルホリン１００ｍｏｌ％からなる実施例１は、耐エッチング性により良好な結果を示し、ウェーハへの外観にも優れたものであった。
　一方、カチオン性の重合開始剤により得られた水溶性高分子を用いた比較例１は、シリカ分散性に大きく劣る結果となった。また、Ｎ－（メタ）アクリロイルモルホリンの使用割合が少ない水溶性高分子を用いた比較例２は、耐エッチング性や濡れ性が十分ではなく、ウェーハの外観にも劣るものであった。比較例３は、Ｎ－（メタ）アクリロイルモルホリンとは異なるアミド系化合物からなる水溶性高分子を使用した実験例であるが、濡れ性及び耐アルカリ性に大きく劣る結果が得られた。比較例４及び５は、従来の研磨用組成物に用いられる水溶性高分子であるセルロース誘導体等を用いた例であるが、ウェーハ表面への吸着性及びシリカ分散性の点で、満足するものではなかった。 Examples 1 to 8 are experimental examples using the water-soluble polymer defined in the present invention, and because the adsorptivity to the wafer is high, results of excellent etching resistance, wettability and appearance to the wafer are obtained. ing. Moreover, it was confirmed that the silica dispersibility is excellent in the case of an abrasive composition. Above all, from the results of Examples 1, 7 and 8 using a water-soluble polymer having the same number average molecular weight and molecular weight distribution, Example 1 comprising 100 mol% of N- (meth) acryloylmorpholine is resistant to etching. The result was excellent, and the appearance on the wafer was also excellent.
On the other hand, Comparative Example 1 using a water-soluble polymer obtained with a cationic polymerization initiator resulted in a greatly inferior silica dispersibility. Further, Comparative Example 2 using a water-soluble polymer with a small proportion of N- (meth) acryloylmorpholine used was not sufficient in etching resistance and wettability, and the wafer appearance was inferior. Comparative Example 3 is an experimental example using a water-soluble polymer composed of an amide compound different from N- (meth) acryloylmorpholine, but the results were greatly inferior in wettability and alkali resistance. Comparative Examples 4 and 5 are examples using cellulose derivatives, which are water-soluble polymers used in conventional polishing compositions, but are satisfactory in terms of adsorptivity to the wafer surface and silica dispersibility. It wasn't.
　本発明の半導体用濡れ剤は、研磨後のウェーハ表面への吸着性に優れるため、該半導体用濡れ剤を含む研磨用組成物を用いることにより、研磨後のウェーハ表面の平滑性を高め、かつ、ＣＯＰを抑制することが可能となる。さらに、シリカの分散性も良好であることから、シリコンウェーハの仕上げ研磨用組成物として特に有用である。 Since the wetting agent for semiconductors of the present invention is excellent in the adsorptivity to the wafer surface after polishing, by using a polishing composition containing the wetting agent for semiconductors, the smoothness of the wafer surface after polishing is improved, and , COP can be suppressed. Furthermore, since the dispersibility of silica is also good, it is particularly useful as a composition for final polishing of silicon wafers.

Claims (6)

  1. 　Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位を５０～１００ｍｏｌ％有し、実質的にカチオン性基を含まない水溶性高分子を含有する半導体用濡れ剤。 A semiconductor wetting agent containing a water-soluble polymer having 50 to 100 mol% of structural units derived from N- (meth) acryloylmorpholine and substantially free of a cationic group.
  2. 　前記Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位が１００ｍｏｌ％である請求項１に記載の半導体用濡れ剤。 The semiconductor wetting agent according to claim 1, wherein the structural unit derived from N- (meth) acryloylmorpholine is 100 mol%.
  3. 　前記水溶性高分子の数平均分子量が、１，０００～３００，０００の範囲であることを特徴とする請求項１又は２に記載の半導体用濡れ剤。 The semiconductor wetting agent according to claim 1 or 2, wherein the water-soluble polymer has a number average molecular weight in the range of 1,000 to 300,000.
  4. 　請求項１～３のいずれかに記載の水溶性高分子の製造方法であって、重合開始剤としてノニオン性及び／又はアニオン性の重合開始剤を使用し、Ｎ－（メタ）アクリロイルモルホリン５０～１００ｍｏｌ％およびその他の単量体０～５０ｍｏｌ％をラジカル重合することを特徴とする水溶性重合体の製造方法。 The method for producing a water-soluble polymer according to any one of claims 1 to 3, wherein a nonionic and / or anionic polymerization initiator is used as a polymerization initiator, and N- (meth) acryloylmorpholine 50 to 50 is used. A method for producing a water-soluble polymer, comprising radically polymerizing 100 mol% and 0 to 50 mol% of another monomer.
  5. 　請求項１～３のいずれかに記載の半導体用濡れ剤、水、砥粒及びアルカリ化合物を含んでなることを特徴とする研磨用組成物。 A polishing composition comprising the semiconductor wetting agent according to any one of claims 1 to 3, water, abrasive grains, and an alkali compound.
  6. 　Ｎ－（メタ）アクリロイルモルホリンに由来する構造単位を５０～１００ｍｏｌ％有し、実質的にカチオン性基を含まない水溶性高分子を用いて、シリコンウェーハを研磨する方法。 A method of polishing a silicon wafer using a water-soluble polymer having 50 to 100 mol% of structural units derived from N- (meth) acryloylmorpholine and substantially free of a cationic group.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017002433A1 (en) * 2015-07-01 2017-01-05 東亞合成株式会社 Wetting agent for polishing and polishing liquid composition
WO2017170179A1 (en) * 2016-03-31 2017-10-05 東亞合成株式会社 Polishing composition and production process therefor
WO2019087818A1 (en) * 2017-11-06 2019-05-09 株式会社フジミインコーポレーテッド Polishing composition and production method therefor
WO2021182276A1 (en) * 2020-03-13 2021-09-16 株式会社フジミインコーポレーテッド Polishing composition

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105732541B (en) * 2016-03-16 2018-07-03 无锡海特圣大光电材料科技有限公司 A kind of monomer with bifunctionality and preparation method thereof
WO2018180479A1 (en) * 2017-03-31 2018-10-04 株式会社フジミインコーポレーテッド Polishing composition

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006112519A1 (en) * 2005-04-14 2006-10-26 Showa Denko K.K. Polishing composition
JP2007273680A (en) * 2006-03-31 2007-10-18 Fujifilm Corp Abrasive compound and polishing method
JP2008055591A (en) * 2006-03-31 2008-03-13 Kohjin Co Ltd Machining speed improver, and water soluble polish/grind agent including machining speed improver
WO2009096495A1 (en) * 2008-02-01 2009-08-06 Fujimi Incorporated Polishing composition and polishing method using the same
JP2011519732A (en) * 2008-04-18 2011-07-14 サン ゴバン アブレシブ インコーポレーティド High porosity abrasive article and method for producing the same
JP2012044197A (en) * 2005-11-11 2012-03-01 Hitachi Chem Co Ltd Polishing agent for silicon oxide, additive liquid and method for polishing
JP2013102176A (en) * 2012-12-25 2013-05-23 Showa Denko Kk Polishing composition

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011171689A (en) * 2009-07-07 2011-09-01 Kao Corp Polishing liquid composition for silicon wafer

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006112519A1 (en) * 2005-04-14 2006-10-26 Showa Denko K.K. Polishing composition
JP2012044197A (en) * 2005-11-11 2012-03-01 Hitachi Chem Co Ltd Polishing agent for silicon oxide, additive liquid and method for polishing
JP2007273680A (en) * 2006-03-31 2007-10-18 Fujifilm Corp Abrasive compound and polishing method
JP2008055591A (en) * 2006-03-31 2008-03-13 Kohjin Co Ltd Machining speed improver, and water soluble polish/grind agent including machining speed improver
WO2009096495A1 (en) * 2008-02-01 2009-08-06 Fujimi Incorporated Polishing composition and polishing method using the same
JP2011519732A (en) * 2008-04-18 2011-07-14 サン ゴバン アブレシブ インコーポレーティド High porosity abrasive article and method for producing the same
JP2013102176A (en) * 2012-12-25 2013-05-23 Showa Denko Kk Polishing composition

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017002433A1 (en) * 2015-07-01 2017-01-05 東亞合成株式会社 Wetting agent for polishing and polishing liquid composition
JPWO2017002433A1 (en) * 2015-07-01 2018-02-01 東亞合成株式会社 Polishing wetting agent and polishing liquid composition
WO2017170179A1 (en) * 2016-03-31 2017-10-05 東亞合成株式会社 Polishing composition and production process therefor
JPWO2017170179A1 (en) * 2016-03-31 2019-02-14 東亞合成株式会社 Polishing composition and method for producing the same
WO2019087818A1 (en) * 2017-11-06 2019-05-09 株式会社フジミインコーポレーテッド Polishing composition and production method therefor
JPWO2019087818A1 (en) * 2017-11-06 2020-12-17 株式会社フジミインコーポレーテッド Polishing composition and its manufacturing method
US11421131B2 (en) 2017-11-06 2022-08-23 Fujimi Incorporated Polishing composition and method for producing same
JP7303111B2 (en) 2017-11-06 2023-07-04 株式会社フジミインコーポレーテッド Polishing composition and method for producing same
US11976220B2 (en) 2017-11-06 2024-05-07 Fujimi Incorporated Polishing composition and method for producing same
WO2021182276A1 (en) * 2020-03-13 2021-09-16 株式会社フジミインコーポレーテッド Polishing composition

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