Aqueous silica compositions for polishing silicon wafers

Abstract

A composition useful in polishing silicon wafers and like materials which comprises an aqueous colloidal silica sol or gel and from 0.1-5% by weight based on the SiO 2 content of the sol or gel of piperazine.

Claims

Having thus described my invention, I claim: 1. An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent comprising an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of a piperazine or a lower alkyl nitrogen-substituted piperazine based on the SiO 2 content of the sol. 2. An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent comprising an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of piperazine based on the SiO 2 content of the sol. 3. An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent comprising an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of a lower alkyl nitrogen-substituted piperazine based on the SiO 2 content of the sol. 4. An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent which comprises an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of a piperazine or a lower alkyl nitrogen-substituted piperazine based on the SiO 2 content of the sol and from 0.1-5% by weight of a water-soluble quaternary ammonium salt or base which contains not more than 6 carbon atoms. 5. An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent which comprises an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of piperazine based on the SiO 2 content of the sol and from 0.1-5% by weight of a water-soluble quaternary ammonium salt or base which contains not more than 6 carbon atoms. 6. An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent which comprises an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of a lower alkyl nitrogen-substituted piperazine based on the SiO 2 content of the sol and from 0.1-5% by weight of a water-soluble quaternary ammonium salt or base which contains not more than 6 carbon atoms. 7. A composition useful in polishing silicon wafers and like materials which comprises an aqueous colloidal silica sol or gel and from 0.1-5% by weight based on the SiO 2 content of the sol or gel of piperazine. 8. A composition useful in polishing silicon wafers and like materials which comprises an aqueous colloidal dispersion of fumed silica having a primary particle size within the range 5-200 nanometer and which additionally contains from 0.1 to 5.0% by weight, based on fumed silica content, of piperazine or a lower alkyl nitrogen-substituted piperazine.
INTRODUCTION This is a continuation-in-part patent application based upon originally filed patent application, Ser. No. 660,683, filed Oct. 15, 1984 now abandoned. U.S. Pat. No. 3,170,273, the disclosure of which is incorporated herein by reference, shows that colloidal silica and silica gels are useful as polishing agents for the surfaces of semi-conductor crystals which are most often used in the manufacture of semi-conductor devices. The siliceous polishing agents of this patent are particularly suited to producing highly polished surfaces on silicon crystal wafers, thus rendering these surfaces suitable for the disposition of an epitaxially deposited crystal layer. The colloidal silica as a sol and silicate gels used by the patentee have an ultimate particle size of 4-200 nanometers. From a commercial standpoint, it is preferred to use as the polishing agents in the process of the patent aqueous colloidal silica sols having particle sizes within the range of 4-100 nanometers. A substantial improvement in polishing efficiency over U.S. Pat. No. 3,170,273 is disclosed in U.S. Pat. No. 4,169,337. The disclosure is incorporated herein by reference. In accordance with that invention, it was found that semi-conductor surfaces of the type previously described and, most particularly, silicon, can be efficiently polished by using as the polishing agent a combination of either a colloidal form of silica or silica gel having an ultimate particle size within the range of 4-200 nanometers and, preferably, 4-100 nanometers, with a water-soluble amine. The amount of amine in relation to the silica present in the silica sol or gel may range between 0.5-5.0% based on the SiO 2 content of the sol or gel. The preferred amount of the amine is 1.0-5.0% and, most preferably, it is 2.0-4.0%. The amines should contain between 2-8 carbon atoms and are preferably aliphatic in character. In U.S. Pat. No. 4,462,188 there are disclosed further improved aqueous silica compositions for polishing silicon wafers. In particular, this patent disclosed that polishing agents used in the practice of U.S. Pat. No. 4,169,337 can be improved substantially if there is added to such compositions between 0.1-5.0% and, most preferably, between 2.0-4.0% by weight of a water-soluble quaternary ammonium salt or base. In a preferred embodiment, the water-soluble quaternary ammonium salts or hydroxides should not contain more than 6 carbon atoms. In a preferred embodiment, they contain one or more alkyl groups that should not exceed 2 carbon atoms in chain length. The compounds may, of course, contain one or more aromatic groupings as long as water-solubility is maintained. They may contain the nitrogen atom as a part of a heterocyclic grouping such as the quaternary ammonium salts of morpholine and the like. Typical water-soluble quaternary ammonium salts and bases that can be used in the invention of U.S. Pat. No. 4,462,188 are tetramethyl ammonium chloride, tetramethyl ammonium hydroxide, dimethyl diethyl ammonium chloride, N,N dimethyl morpholinium sulfate and tetrabutyl ammonium bromide. Of these materials, tetramethyl ammonium chloride is preferred. THE INVENTION The invention comprises an improved method for polishing silicon wafers and like materials which comprises using as a polishing agent a colloidal silica or a gel which is combined with 0.1%-5% by weight of a piperazine or a lower alkyl nitrogen-substituted piperazine based on the SiO 2 content of the sol. The piperazine may be combined with an additional 0.1-5% by weight of a wter-soluble quaternary ammonium salt or base which contains not more than 6 carbon atoms. The Starting Silica Sols As indicated, a wide variety of aqueous colloidal silicas or gels may be used in the practice of the invention. The colloidal silicas are preferred. Two such materials are sold under the designation NALCOAG 1050 and NALCOAG 1060. These silica sols and their properties are described below: ______________________________________NALCOAG 1050Colloidal silica as SiO.sub.2 = 50%pH = 9.0Average Particle Size = 16-25 nmAverage Surface Area = 120-176 M.sup.2 /gramSpecific Gravity (at 68° F.) = 1.390Viscosity = 70 cps (maximum)Na.sub.2 O content = 0.4%NALCOAG 1060Colloidal silica as SiO.sub.2 = 50%pH = 8.5Average Particle Size = 50-70 nmAverage Surface Area = 40-60 M.sup.2 /gramSpecific Gravity (at 68° F.) = 1.390Viscosity at 77° F. = 15 cps (maximum)______________________________________ In addition to those sols described above, other silica sols as well as their method of manufacture is set forth and described in U.S. Pat. No. 3,901,992, which is incorporated herein by reference. Finally, we have discovered that improved results can be obtained when the silica sols and/or gels are obtained by dispersing fumed silica into an aqueous media containing the piperazine compounds. The Piperazine or Lower Alkyl Nitrogen Substituted Piperazine These amines comprise piperazine itself as well as piperazines containing lower alkyl substituents on the nitrogen portion of the piperazine molecules. The lower alkyl nitrogen-substituted pierazines may be illustrated by piperazines having lower alkyl groups containing from 1-4 carbon atoms. The alkyl groups may be composed of hydrogen and carbon although they may contain other substituents such as OH, amino groups and the like. Lower alkyl nitrogen-substituted piperazines that may be used in the practice of the invention are the following compounds: N--Aminoethylpiperazine 1,4--Bis (3-aminopropyl) piperazine Of the above compounds, piperazine is preferred. The amount of piperazine or lower alkyl nitrogen-substituted piperazines that are used is between 0.1-5% by weight based on the weight of the SiO 2 content of the aqueous silica. The preferred amount is 1.0-5% and, most preferably, 2-4%. As indicated in U.S. Pat. Nos. 4,169,337 and 4,462,188 previously cited, the polishing operation is conducted at alkaline pH's usually in excess of 10. Thus it is necessary to adjust the polishing solutions to a pH of about 11 or greater. This may be done with either a sodium base or a potassium base depending upon the particular effects thought to be achieved in the final polishing operation. Advantages of the Invention Piperazine in combination with silica sols for wafer polishing applications offers a number of advantages as does piperazine in combination with fumed silicas. The advantages can be summarized as follows: 1. Piperazine at a 2% level requires less colloidal silica than aminoethylethanolamine to give the same polishing rate. 2. Piperazine in the presence of colloidal silica shows no discoloration of the product with time. 3. Piperazine at a 2% level in the presence of colloidal silica requires no additional chemical to kill or inhibit microbiological growths. 4. Silica wafer polishing requires high pH's. Piperazine systems being highly basic require less caustic to make pH adjustments. 5. Fumed silica aqueous/dispersions in the presence of piperazine show +10.6% to +18.2% improvement in polishing rate over colloidal silicas containing piperazine at the same silica level (2.4%) or with colloidal silicas containing aminoethylethanolamine at a higher silica level (3.2%). For example, 30 grams of Cabosil M-5 were dispersed in 67.78 grams of water containing 0.22% potassium hydroxide and 2.0% piperazine flake. The dispersed fumed silica formulation, when diluted one part product plus fourteen parts of water, produced the above polishing resuts. EXAMPLES To illustrate the advantages of the invention, a polishing test was conducted as described and set forth in U.S. Pat. No. 4,169,337. The results of these tests are set forth below. In the tests to be described hereinafter, the compositions of the invention were compared against a commercial silica gel amine-containing product which is of the type described in U.S. Pat. No. 4,169,337. This product is an aqueous colloidal silica gel. It has an average particle size of 50-100 nanometers, is sodium stabilized, and contains 50% by weight of colloidal silica particles and 2% by weight of aminoethylethanolamine. Similar results are obtained with piperazine plus bases other than sodium hydroxide. This commercial material is hereafter referred to as Composition 1. ______________________________________ GLOSSARYProducts for Silicon Wafer Polishing______________________________________Comp. 2 Na-Stab 40% SiO.sub.2 plus 1.2% piperazineComp. 3 Na-Stab 40% SiO.sub.2 plus 1.6% piperazineComp. 4 Na-Stab 40% SiO.sub.2 plus 2.0% piperazineComp. 5 Na-Stab 40% SiO.sub.2 plus 2.5% piperazineComp. 6 Na-Stab 40% SiO.sub.2 plus 3.0% piperazineComp. 7 K-Stab 40% SiO.sub.2 plus 1.6% piperazineComp. 8 K-Stab 40% SiO.sub.2 plus 2.0% piperazineComp. 9 Na-Stab 40% SiO.sub.2 plus 2.0% piperazine plus 140 ppm EDAComp. 10 Commercial 30% SiO.sub.2 Silica 1Comp. 11 Experimental 30% SiO.sub.2 plus 2.0% piperazine silica, K-StabComp. 12 Experimental 30% SiO.sub.2 plus 2.0% piperazine silica, K-StabComp. 13 Exp. silica, 30% SiO.sub.2 plus 2.0% piperazine K-Stab______________________________________ TABLE I__________________________________________________________________________SUMMARY OF STRASBAUGH POLISHING MACHINE TESTS Amt. 45% % SiO.sub.2 KOH Used Pressure Temp. Polishing No. of Polish Rate* % Diff.Dilution Used pH per 10 L (psi) (°C.) Time Runs mils/10 min. from 2350__________________________________________________________________________Comp. 120/1 3.2 11.1 6.6 gm 8 49-51 10 5 0.93 --Comp. 220/1 2.4 11.2 6.6 gm 8 46-52 10 2 0.89 -4.4%Comp. 320/1 2.4 11.1 6.6 gm 8 48-51 10 3 0.94 +1.1%Comp. 420/1 2.4 11.1 6.6 gm 8 47-51 10 2 0.96 +3.2%Comp. 520/1 2.4 11.1 6.6 gm 8 47-51 10 2 0.98 +5.4%Comp. 620/1 2.4 11.1 6.6 gm 8 47-51 10 2 0.97 +4.3%Comp. 720/1 2.4 11.1 6.6 gm 8 44-51 10 2 0.93 0Comp. 820/1 2.4 11.2 6.6 gm 8 43-49 10 2 0.91 -2.2%Comp. 120/1 3.2 10.6 6.6 gm 8 46-51 10 3 0.95 --Comp. 820/1 2.4 11.0 6.6 gm 8 47-52 10 2 0.94 -1.0%Comp. 920/1 2.4 11.2 6.6 gm 8 46-51 10 2 0.94 -1.0%__________________________________________________________________________ TABLE II__________________________________________________________________________SUMMARY OF STRASBAUGH POLISHING MACHINE TESTS Amt. 45% % SiO.sub.2 KOH Used Pressure Temp. Polishing No. of Polish Rate* % Diff.Dilution Used pH per 10 L (psi) (°C.) Time Runs mils/10 min. from 2350__________________________________________________________________________Comp. 120/1 3.2 11.0 6.6 gm 8 47-51 10 5 0.96 --Comp. 820/1 2.4 11.2 6.6 gm 8 45-50 10 3 0.94 -2.1%Comp. 1010/1 3.2 11.0 6.6 gm 8 44-53 10 2 0.66 -31.2%Comp. 1110/1 3.2 11.1 13.2 gm 8 45-51 10 2 1.08 +12.5%__________________________________________________________________________ TABLE III__________________________________________________________________________SUMMMARY OF STRASBAUGH POLISHING MACHINE TESTS Amt. 45% % SiO.sub.2 KOH Used Pressure Temp. Polishing No. of Polish Rate* % Diff.Dilution Used pH per 10 L (psi) (°C.) Time Runs mils/10 min. from 2350__________________________________________________________________________Comp. 120/1 3.2 11.1 6.6 gm 6.8 44-51 10 2 0.91 --Comp. 1114/1 2.4 11.1 9.9 gm 6.8 44-52 10 1 1.04 +14.3%Comp. 12 6/1 3.2 11.1 6.6 gm 6.8 45-52 10 2 1.06 +16.5%Comp. 1310/1 3.2 11.0 6.6 gm 6.8 44-51 10 2 1.04 +14.3%Comp. 120/1 3.2 11.2 6.6 gm 6.8 44-51 10 2 0.90 --Comp. 820/1 2.4 10.4 6.6 gm 6.8 43-51 10 2 0.90 0Comp. 1114/1 2.4 10.7 9.9 gm 6.8 45-52 10 2 1.04 +15.6%Comp. 1110/1 3.2 10.8 13.2 gm 6.8 45-52 10 2 1.09 +21.1%__________________________________________________________________________ TABLE IV__________________________________________________________________________SILTEC POLISHING MACHINE TESTS Amt. 45% % SiO.sub.2 KOH Used Pressure Temp. Polishing Run Polish Rate* % Diff.Dilution Used pH per 10 L (psi) (°C.) Time No. mils/10 min. from 2350__________________________________________________________________________Comp. 120/1 3.2 11.1 6.6 gm 6.4 40-51 20 1 0.85 2 0.86 3 0.86 4 0.87 5 0.89 AVE. = 0.87Comp. 820/1 2.4 11.2 6.6 gm 6.4 40-51 20 1 0.83 2 0.83 3 0.83 4 0.86 5 0.84 AVE. = 0.84 -3.4%Comp. 1010/1 3.2 11.0 6.6 gm 6.4 40-51 20 0.50 -42.5%__________________________________________________________________________ TABLE V__________________________________________________________________________SUMMARY OF SILTEC POLISHING TESTSPressure - 6.8 psiPolishing Time - 20 minutes Amt. 45% % SiO.sub.2 KOH Used Temp. No. of Polish Rate* % Diff.Dilution Used pH per 10 L (°C.) Wafers mils/10 min. from 2350__________________________________________________________________________Comp. 1 20/1 3.2 11.2 6.6 gm 40-51 28 0.86 --Comp. 1 20/1 3.2 10.9 6.6 gm 40-50 28 0.89 --Comp. 8 20/1 2.4 11.2 6.6 gm 40-50 28 0.89 --Comp. 8 20/1 2.4 10.9 6.6 gm 40-51 28 0.84 -4.5% Comp. 11 14/1 2.4 11.1 9.9 gm 40-51 28 1.04 +18.2% Comp. 11 14/1 2.4 10.9 9.9 gm 43-51 28 1.04 +18.2%Comp. 1 20/1 3.2 11.2 6.6 gm 39-50 28 0.83 --Comp. 1 20/1 3.2 10.9 6.6 gm 40-51 28 0.85 -- Comp. 11 20/1 1.7 11.1 14.1 gm 40-50 28 0.92 +4.5% Comp. 11 20/1 1.7 10.8 14.1 gm 40-50 28 0.91 +3.4%__________________________________________________________________________ TABLE VI______________________________________EFFECT OF PARTICLE SIZE AND PIPERAZINECONCENTRATION ON POLISHING RATE % ChangeSilica Sol PD Piperazine (1) Polishing Rate* fromUsed (nm) Concentration (mils/10 min.) Comp. 1______________________________________Nalco 1050 20 5% 1.42 +1.4%Nalco 1060 60 5% 1.43 +2.1%Exp..sub.Sol Silica 75 2% 1.46 +4.3%Exp..sub.Sol Silica 75 4% 1.47 +5.0%Exp..sub.Sol Silica 75 5% 1.59 +13.6%Exp..sub.Sol Silica 75 7% 1.41 +0.7%Exp..sub.Sol Silica 75 10% 1.27 -9.3%______________________________________ Comp. 1 Polishing Rate = 1.40 mils/10 min. TABLE VII______________________________________EFFECT OF SUBSTITUTED PIPERAZINESON POLISHING RATE Polishing Rate* % Change Concen- (mils/ fromType of Piperazine Compound tration 10 min.) Comp. 1______________________________________Piperazine 2% 1.46 +4.3%N--Aminoethyl piperazine 2% 1.35 -3.6%1,4 Bis(3-Aminopropyl) 2% 1.58 +12.8%piperazine pad damage1,4 Bis(3-Aminopropyl) 4% 1.62 +15.7%piperazine pad damage______________________________________ In all of the compositions listed above, unless otherwise mentioned, the starting silica material was colloidal silica used in Comp. 1 diluted to 40% by weight silica. Also, in all of the tests listed, piperazine was used. Table VII shows the effect of polishing with nitrogen-substituted piperazines. Some of these materials are either less effective than piperazine or cause pad damage, with existing polishing pad materials.

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Patent Citations (7)

    Publication numberPublication dateAssigneeTitle
    US-3170273-AFebruary 23, 1965Monsanto CoProcess for polishing semiconductor materials
    US-3715842-AFebruary 13, 1973Tizon Chem CorpSilica polishing compositions having a reduced tendency to scratch silicon and germanium surfaces
    US-3877183-AApril 15, 1975Wacker Chemie GmbhMethod of polishing semiconductor surfaces
    US-3922393-ANovember 25, 1975Du PontProcess for polishing silicon and germanium semiconductor materials
    US-4057939-ANovember 15, 1977International Business Machines CorporationSilicon wafer polishing
    US-4169337-AOctober 02, 1979Nalco Chemical CompanyProcess for polishing semi-conductor materials
    US-4462188-AJuly 31, 1984Nalco Chemical CompanySilica sol compositions for polishing silicon wafers

NO-Patent Citations (0)

    Title

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    US-2007095677-A1May 03, 2007Applied Materials, Inc.Electrochemical method for ecmp polishing pad conditioning
    US-6500870-B1December 31, 2002Akzo Nobel N.V.Method for manufacturing of silica sols
    US-2003209523-A1November 13, 2003Applied Materials, Inc.Planarization by chemical polishing for ULSI applications
    US-2007227902-A1October 04, 2007Applied Materials, Inc.Removal profile tuning by adjusting conditioning sweep profile on a conductive pad
    US-5913712-AJune 22, 1999Cypress Semiconductor Corp.Scratch reduction in semiconductor circuit fabrication using chemical-mechanical polishing
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    US-2006248804-A1November 09, 2006Masato Yoshida, Toranosuke Ashizawa, Hiroki Terazaki, Yuuto Ootuki, Yasushi Kurata, Jun Matsuzawa, Kiyohito TannoAbrasive, method of polishing target member and process for producing semiconductor device
    US-7141155-B2November 28, 2006Parker-Hannifin CorporationPolishing article for electro-chemical mechanical polishing
    EP-1422277-A1May 26, 2004Nippon Aerosil Co., Ltd.Pâté de silice a haute concentration
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    US-2006088999-A1April 27, 2006Applied Materials, Inc.Methods and compositions for chemical mechanical polishing substrates
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    US-5226930-AJuly 13, 1993Monsanto Japan, Ltd.Method for preventing agglomeration of colloidal silica and silicon wafer polishing composition using the same
    US-2004159558-A1August 19, 2004Bunyan Michael H., Clement Thomas A., Hannafin John J., Larosee Marc E., Young Kent M.Polishing article for electro-chemical mechanical polishing
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    WO-0146072-A1June 28, 2001Akzo Nobel N.V., Eka Chemicals AbSilica-based sols
    US-7534277-B2May 19, 2009Cheil Industries, Inc.Slurry composition for secondary polishing of silicon wafer
    US-7220322-B1May 22, 2007Applied Materials, Inc.Cu CMP polishing pad cleaning
    EP-0375258-A2June 27, 1990AT&T Corp.Method of fabricating a flat wafer
    US-7708788-B2May 04, 2010Hitachi Chemical Co, Ltd.Cerium oxide abrasive and method of polishing substrates
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    US-2004023491-A1February 05, 2004Young-Sam Lim, Gi-Hag Lee, Lee Dong-Jun, Kyoung-Moon Kang, Jae-Hyun So, Nam-Soo KimPreparation and use of an abrasive slurry composition
    US-6114249-ASeptember 05, 2000International Business Machines CorporationChemical mechanical polishing of multiple material substrates and slurry having improved selectivity
    US-5230833-AJuly 27, 1993Nalco Chemical CompanyLow sodium, low metals silica polishing slurries
    US-2004098924-A1May 27, 2004Shoji IwasaPolishing composition and rinse composition
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    US-2004127047-A1July 01, 2004Shuhei Yamada, Akihiro KawasePolishing composition and polishing method using the same
    US-2003216049-A1November 20, 2003Applied Materials, Inc.Method and composition for the removal of residual materials during substrate planarization
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    US-2005204639-A1September 22, 2005Naoyuki IshiharaPolishing composition and polishing method
    US-6451697-B1September 17, 2002Applied Materials, Inc.Method for abrasive-free metal CMP in passivation domain
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    US-2009253813-A1October 08, 2009Yuko Ishiguri, Kunio Ohkubo, Yukiyo Saito, Masahiro Izumi, Masaru Nakajo, Kuniaki Maejima, Hiroaki TanakaColloidal silica consisting of silica particles fixing nitrogen contained alkaline compound
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    US-5203882-AApril 20, 1993Norton CompanyBonding adjuvants for vitreous bond formulations and process for bonding with
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    US-7005382-B2February 28, 2006Jsr Corporation, Kabushiki Kaisha ToshibaAqueous dispersion for chemical mechanical polishing, chemical mechanical polishing process, production process of semiconductor device and material for preparing an aqueous dispersion for chemical mechanical polishing
    US-5157876-AOctober 27, 1992Rockwell International CorporationStress-free chemo-mechanical polishing agent for II-VI compound semiconductor single crystals and method of polishing
    US-2007158207-A1July 12, 2007Applied Materials, Inc.Methods for electrochemical processing with pre-biased cells
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    US-6524167-B1February 25, 2003Applied Materials, Inc.Method and composition for the selective removal of residual materials and barrier materials during substrate planarization
    KR-100803876-B1January 09, 2003닛산 가가쿠 고교 가부시키 가이샤연마용 조성물
    US-2004129176-A1July 08, 2004Nippon Aerosil Co., Ltd.High concentration silica slurry
    US-2005282718-A1December 22, 2005Hiroyuki NakagawaRinsing composition, and method for rinsing and manufacturing silicon wafer
    EP-0962508-A1December 08, 1999Fujimi IncorporatedComposition de polissage du bord d'une plaquette semi-conductrice
    US-6811470-B2November 02, 2004Applied Materials Inc.Methods and compositions for chemical mechanical polishing shallow trench isolation substrates
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    WO-0185868-A1November 15, 2001Nissan Chemical Industries, Ltd.Polishing composition
    US-2007186486-A1August 16, 2007Fujimi IncorporatedPolishing composition and rinse composition
    US-2005205837-A1September 22, 2005Toshihiro MiwaPolishing composition and polishing method
    US-6719819-B2April 13, 2004Nissan Chemical Industries, Ltd.Polishing composition
    US-7772173-B2August 10, 2010Fujimi IncorporatedRinsing composition, and method for rinsing and manufacturing silicon wafer
    US-6340374-B1January 22, 2002Tokuyama CorporationPolishing slurry and polishing method
    EP-0520109-A1December 30, 1992Rodel, Inc.Low sodium, low metals silica polishing slurries
    US-7481950-B2January 27, 2009Fujimi IncorporatedPolishing composition and polishing method using the same
    GB-2412919-AOctober 12, 2005Fujimi IncPolishing composition
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    US-2006046623-A1March 02, 2006Applied Materials, Inc.Method and apparatus for reduced wear polishing pad conditioning
    US-2007181851-A1August 09, 2007Shuhei YamadaPolishing composition and polishing method
    US-2006242912-A1November 02, 2006Roh Hyun S, Park Tae W, Lee Kill S, Lee In KSlurry composition for secondary polishing of silicon wafer
    US-7210988-B2May 01, 2007Applied Materials, Inc.Method and apparatus for reduced wear polishing pad conditioning
    CN-102766408-ANovember 07, 2012深圳市力合材料有限公司, 深圳清华大学研究院, 清华大学Silicon wafer refined polishing composition liquid applicable to low pressure and preparation method thereof
    US-6569349-B1May 27, 2003Applied Materials Inc.Additives to CMP slurry to polish dielectric films
    US-2006118524-A1June 08, 2006Hitachi Chemical Co., Ltd.Cerium oxide abrasive and method of polishing substrates
    US-8721909-B2May 13, 2014Fujimi IncorporatedPolishing composition and polishing method
    US-2009137123-A1May 28, 2009Fujimi IncorporatedPolishing Composition and Polishing Method
    US-6852020-B2February 08, 2005Raytech Innovative Solutions, Inc.Polishing pad for use in chemical—mechanical planarization of semiconductor wafers and method of making same
    EP-0375258-A3March 20, 1991AT&T Corp.Method of fabricating a flat wafer
    US-2005054203-A1March 10, 2005Shuhei YamadaPolishing composition
    US-2009197413-A1August 06, 2009Fijimi IncorporatedPolishing Composition and Polishing Method Using The Same
    US-2008051010-A1February 28, 2008Yasuhide UemuraPolishing Composition and Polishing Method
    US-6280652-B1August 28, 2001Fujimi IncorporatedEdge polishing composition
    US-2010003821-A1January 07, 2010Fujimi IncorporatedWetting agent for semiconductors, and polishing composition and polishing method employing it
    US-2009291559-A1November 26, 2009Cabot Microelectronics CorporationStable, high rate silicon slurry
    US-6083419-AJuly 04, 2000Cabot CorporationPolishing composition including an inhibitor of tungsten etching
    US-6638982-B2October 28, 2003Cabot CorporationMethod of preparing a fumed metal oxide dispersion
    US-7963825-B2June 21, 2011Hitachi Chemical Company, Ltd.Abrasive, method of polishing target member and process for producing semiconductor device
    US-2011217845-A1September 08, 2011Fujimi, Inc.Polishing Composition and Polishing Method Using The Same
    US-8616936-B2December 31, 2013Hitachi Chemical Company, Ltd.Abrasive, method of polishing target member and process for producing semiconductor device
    US-2003153189-A1August 14, 2003Applied Materials, Inc.Low cost and low dishing slurry for polysilicon CMP
    US-2006021972-A1February 02, 2006Lane Sarah J, Mueller Brian L, Charles YuCompositions and methods for chemical mechanical polishing silicon dioxide and silicon nitride
    US-8162725-B2April 24, 2012Hitachi Chemical Company, Ltd.Abrasive, method of polishing target member and process for producing semiconductor device
    US-2008127573-A1June 05, 2008Cheil Industries Inc.Slurry Composition for Final Polishing of Silicon Wafers and Method for Final Polishing of Silicon Wafers Using the Same
    US-2004142637-A1July 22, 2004Angela Petroski, Cooper Richard D., Paul Fathauer, Yesnik Marc AndrewPolishing pad for use in chemical-mechanical planarization of semiconductor wafers and method of making same
    EP-1041129-A1October 04, 2000Tokuyama CorporationPolishing slurry and polishing method
    US-7504018-B2March 17, 2009Applied Materials, Inc.Electrochemical method for Ecmp polishing pad conditioning
    US-2003027499-A1February 06, 2003Cabot Microelectronics CorporationComposition and method for polishing rigid disks
    US-2006088976-A1April 27, 2006Applied Materials, Inc.Methods and compositions for chemical mechanical polishing substrates
    CN-104099027-AOctober 15, 2014罗门哈斯电子材料Cmp控股股份有限公司Silicon wafer polishing composition and related methods
    US-2006151854-A1July 13, 2006Akihiro Kawase, Toshihiro Miwa, Kenji Sakamoto, Ichiro HayashidaPolishing composition and rinsing composition
    US-7104267-B2September 12, 2006Applied Materials Inc.Planarized copper cleaning for reduced defects
    EP-2297263-A2March 23, 2011Cabot Microelectronics CorporationStable, high rate silicon slurry
    US-2004132305-A1July 08, 2004Jsr Corporation, Kabushiki Kaisha ToshibaAqueous dispersion for chemical mechanical polishing, chemical mechanical polishing process, production process of semiconductor device and material for preparing an aqueous dispersion for chemical mechanical polishing
    US-7022608-B2April 04, 2006Applied Materials Inc.Method and composition for the removal of residual materials during substrate planarization
    US-7192461-B2March 20, 2007Nippon Aerosil Co., Ltd.High concentration silica slurry
    US-2009032075-A1February 05, 2009Applied Materials, Inc.Methods and apparatus for liquid chemical delivery
    US-2003143848-A1July 31, 2003Cabot Microelectronics CorporationChemical mechanical polishing slurry and method for using same
    US-2008214000-A1September 04, 2008Hiroshi Asano, Tetsuji HoriPolishing composition and polishing method using the same
    US-2003054667-A1March 20, 2003Applied Materials, Inc.Method of improving moisture resistance of low dielectric constant films
    US-7998229-B2August 16, 2011Fujimi IncorporatedPolishing composition and polishing method
    US-6976905-B1December 20, 2005Cabot Microelectronics CorporationMethod for polishing a memory or rigid disk with a phosphate ion-containing polishing system
    US-2005108947-A1May 26, 2005Mueller Brian L., Haofeng XuCompositions and methods for chemical mechanical polishing silica and silicon nitride
    WO-9322103-A1November 11, 1993Rodel, Inc.Compositions and methods for polishing and planarizing surfaces