Composition for semiconductor processing and processing method

Abstract

The present invention provides: a composition for semiconductor processing which has excellent storage stability and which can effectively reduce the occurrence of corrosion and defects in a wiring material on the surface of an object to be processed; and a processing method using the same.　A composition for semiconductor processing according to the present invention contains a heterocyclic compound (A), a cationic water-soluble polymer (B), and a liquid medium (C), wherein, provided that the (A) component content is defined as MA [parts by mass] and the component (B) component content is defined as MB [parts by mass], MA / MB = 0.1–1000 and the pH is 2–9.

Description

Composition and Processing Method for Semiconductor Processing

[0001] The present invention relates to a composition for semiconductor cleaning and a processing method using the same.

[0002] With the improvement of semiconductor manufacturing technology, higher integration and faster operation of semiconductor devices are required. Along with this, the flatness of the semiconductor substrate surface required in the manufacturing process of fine semiconductors in semiconductor devices has become increasingly strict, and chemical mechanical polishing (CMP) has become an indispensable technology in the semiconductor device manufacturing process.

[0003] For example, tungsten with excellent embedding properties is used for contact holes that electrically connect between wirings in the vertical and horizontal directions. As a composition for chemical mechanical polishing used for polishing such a tungsten film, a composition containing an oxidizing agent such as hydrogen peroxide, an iron catalyst such as iron nitrate, and abrasive grains such as silica has been proposed (for example, see Patent Documents 1 to 3).

[0004] In addition, in the manufacture of semiconductor devices, after a CMP process or the like, a cleaning process for removing contamination such as polishing debris and organic residues from the surface of the semiconductor substrate is essential. Since wiring materials such as tungsten are exposed on the surface of the semiconductor substrate, it is necessary to suppress corrosion of the polished surface where such wiring materials are exposed in the cleaning process. In such a cleaning process, a technique for suppressing corrosion of the surface of the semiconductor substrate has been proposed (for example, see Patent Document 4).

[0005] JP-A-2020-50861 JP-A-2020-77860 WO 2022 / 172,438 JP-A-2011-159,658

[0006] Chemical mechanical polishing compositions used to polish tungsten films typically have an acidic pH of around 2-5, as they need to oxidize the tungsten surface to create an oxide film. Therefore, corrosion and defects are likely to occur on the tungsten surface after CMP (Computer Polishing). Chemical mechanical polishing compositions used to polish tungsten films are required to have properties that minimize the occurrence of corrosion and defects on the tungsten surface. Furthermore, to further enhance the production stability of semiconductor devices, it is also necessary to improve the storage stability of chemical mechanical polishing compositions.

[0007] On the other hand, cleaning agents used to clean the tungsten surface after CMP (Computerized Multi-Purpose) treatment are required to have properties that minimize corrosion and defect occurrence on the tungsten surface.

[0008] Some aspects of the present invention provide a semiconductor processing composition that has excellent storage stability and can effectively reduce corrosion and defects in the wiring material on the surface of a workpiece, and a processing method using the same, by solving at least some of the above problems.

[0009] The present invention has been made to solve at least some of the above-mentioned problems and can be realized in any of the following embodiments.

[0010] One embodiment of the semiconductor processing composition according to the present invention contains (A) a heterocyclic compound, (B) a cationic water-soluble polymer, and (C) a liquid medium, wherein when the content of component (A) is MA [parts by mass] and the content of component (B) is MB [parts by mass], MA / MB = 0.1 to 1000 and the pH is 2 to 9.

[0011] In one embodiment of the semiconductor processing composition, component (A) may be a nitrogen-containing heterocyclic compound.

[0012] In any embodiment of the semiconductor processing composition, the nitrogen-containing heterocyclic compound may have an isothiazolin structure or a thiazole structure.

[0013] In any embodiment of the semiconductor processing composition, the number-average molecular weight (Mn) of component (B) may be 1,000 or more and 20,000 or less.

[0014] In any embodiment of the semiconductor processing composition, abrasive particles may be further included.

[0015] One embodiment of the processing method according to the present invention includes a step of processing using a semiconductor processing composition according to any of the above embodiments.

[0016] The semiconductor processing composition according to the present invention exhibits minimal deterioration in polishing properties even after long-term storage, and can be stably used in the manufacture of semiconductor devices. Furthermore, the semiconductor processing composition according to the present invention can effectively reduce the occurrence of corrosion and defects in the wiring material on the surface of the workpiece. The semiconductor processing composition according to the present invention is particularly effective when processing wiring substrates containing tungsten or the like as the wiring material.

[0017] Figure 1 is a schematic cross-sectional view showing a workpiece suitable for use in the processing method according to this embodiment. Figure 2 is a schematic cross-sectional view showing the processing method according to this embodiment. Figure 3 is a schematic perspective view showing a semiconductor processing apparatus. Figure 4 is a schematic cross-sectional view showing a patterned wafer used in the example.

[0018] Preferred embodiments of the present invention will be described in detail below. However, the present invention is not limited to the embodiments described below, and includes various modifications that do not alter the essence of the invention.

[0019] 1. A semiconductor processing composition according to one embodiment of the present invention contains (A) a heterocyclic compound (hereinafter also referred to as "component (A)"), (B) a cationic water-soluble polymer (hereinafter also referred to as "component (B)"), and (C) a liquid medium, wherein the content of component (A) is MA [parts by mass] and the content of component (B) is MB [parts by mass], the ratio MA / MB = 0.1 to 1000 and the pH is 2 to 9.

[0020] The semiconductor processing composition according to this embodiment may be prepared by diluting the stock solution composition (concentrated type) with a liquid medium such as pure water or an organic solvent as needed, or the stock solution composition (undiluted type) may be used as is without dilution. In this specification, unless otherwise specified, the term "stock solution composition" shall be interpreted as a concept that includes both concentrated and undiluted types.

[0021] Furthermore, the semiconductor processing composition according to this embodiment can be used as a semiconductor processing composition such as a CMP slurry for chemical mechanical polishing, a cleaning agent for removing particles and metal impurities present on the surface of a workpiece after CMP is completed, a resist stripping agent for stripping resist from a semiconductor substrate processed with resist, and an etching agent for removing surface contamination by shallow etching of the surface of wiring materials, etc.

[0022] In other words, the "semiconductor processing composition" in the present invention refers to a composition prepared by adding a liquid medium to the above-mentioned stock solution composition (concentrated type) and diluting it, or the above-mentioned stock solution composition (undiluted type) itself, which is actually used when processing the surface of an object to be processed. The above-mentioned stock solution composition (concentrated type) usually exists in a concentrated state. Therefore, each user can prepare a semiconductor processing composition by diluting the above-mentioned stock solution composition (concentrated type) with a liquid medium, or use the stock solution composition (undiluted type) as is as a semiconductor processing composition, and use that semiconductor processing composition as a CMP slurry for chemical mechanical polishing, a cleaning agent for cleaning semiconductor surfaces, a resist stripping agent, or an etching agent. The components that may be included in the semiconductor processing composition according to this embodiment will be described in detail below.

[0023] 1.1. Component (A) The semiconductor processing composition according to this embodiment contains a heterocyclic compound (A). Component (A) is adsorbed onto the surface of the workpiece where wiring material such as tungsten is exposed, thereby reducing the occurrence of corrosion.

[0024] Component (A) is preferably a nitrogen-containing heterocyclic compound. Here, a nitrogen-containing heterocyclic compound is an organic compound containing at least one heterocyclic ring selected from heterofive-membered rings and heterosix-membered rings, having at least one nitrogen atom. Specific examples of the heterocyclic ring include heterofive-membered rings such as pyrrole structures, imidazole structures, triazole structures, thiazole structures, and isothiazoline structures; and heterosix-membered rings such as pyridine structures, pyrimidine structures, pyridazine structures, and pyrazine structures. The heterocyclic ring may form a fused ring. Specifically, examples include indole structures, isoindole structures, benzimidazole structures, benzotriazole structures, quinoline structures, isoquinoline structures, quinazoline structures, cinnoline structures, phthalazine structures, quinoxaline structures, and acridine structures. Among nitrogen-containing heterocyclic compounds having such structures, nitrogen-containing heterocyclic compounds having an isothiazolin structure, thiazole structure, pyridine structure, quinoline structure, benzimidazole structure, or benzotriazole structure are preferred, and nitrogen-containing heterocyclic compounds having an isothiazolin structure or thiazole structure are more preferred.

[0025] Specific examples of nitrogen-containing heterocyclic compounds include aziridine, pyridine, pyrimidine, pyrrolidine, piperidine, pyrazine, triazine, pyrrole, imidazole, indole, quinoline, isoquinoline, benzoisoquinoline, purine, pteridine, triazole, triazolidine, benzotriazole, carboxybenzotriazole, thiazole, benzothiazole, 4-bromothiazole, 2-chlorothiazole, 2-mercaptobenzothiazole, 2-(methylthio)benzothiazole, 2-chlorobenzothiazole, 2-methylbenzothiazole, 5-methoxy-2-methylbenzothiazole, 2-methyl-4,5,7-trifluorobenzothiazole, 2-aminobenzothiazole, 2-amino-6-methylbenzothiazole, 2-amino-4-methoxybenzothiazole, 4-methyl-2-mercaptobenzothiazole, 3-chloro-1,2-benzoisothiazole, 2-(2-Hyd Roxyphenyl) benzothiazole, 2-mercapto-2-thiazoline, thiazoline, chlorothiazoline, isothiazolinone, 1,2-benzisothiazolinone, chloromethylisothiazolinone, 2-methyl-4,5-trimethylene-4-isothiazolinone-3-one, 5-chloro-2-methyl-4-isothiazolinone-3-one, N-n-butyl-1,2-benzoisothiazolinone-3-one, 2-n-octyl-4-isothiazolinone-3-one, 4 Examples include 5-dichloro-2-n-octyl-isothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 1,2-benzoisothiazole-3(2H)-one, 2-n-octyl-4-isothiazolin-3-one, 2-benzothiazolethiol, 2-methyl-4-isothiazolin-3-one, 2-mercapto-2-thiazoline, 5-chloro-2-methyl-3-isothiazolon, isothiazole, benzothiazole, etc. These nitrogen-containing heterocyclic compounds may be used individually or in combination of two or more.

[0026] In such a semiconductor processing composition, the content (MA) of component (A) is preferably 0.001 parts by mass or more, more preferably 0.005 parts by mass or more, and particularly preferably 0.008 parts by mass or more, when the total mass of the semiconductor processing composition is 100 parts by mass. The content of component (A) is preferably 1 part by mass or less, more preferably 0.75 parts by mass or less, and particularly preferably 0.65 parts by mass or less, when the total mass of the semiconductor processing composition is 100 parts by mass. When the content of component (A) is within the above range, component (A) is adsorbed onto the wiring metal exposed on the surface of the object to be processed, thereby inhibiting corrosion, and component (A) can be easily removed in the cleaning process after processing, thereby reducing the occurrence of defects.

[0027] 1.2. Component (B) The semiconductor processing composition according to this embodiment contains (B) a cationic water-soluble polymer. In the present invention, "water-soluble" means that the mass that dissolves in 100 g of water at 20°C is 0.1 g or more. Component (B) can suppress the excessive adsorption and residue of component (A) on the surface of the workpiece, and as a result, the occurrence of defects on the surface of the workpiece can be reduced.

[0028] Examples of component (B) include polyethyleneimine, polyvinylpyrrolidone, polyvinylamine, polyvinylpyridine, polyallylamine, polyvinylpiperazine, polylysine, and polyhexamethylene biguanide. Among these, at least one selected from the group consisting of polylysine and polyhexamethylene biguanide is preferred, and polylysine is more preferred. In the semiconductor processing composition according to this embodiment, these components (B) can be used individually or in combination of two or more.

[0029] The number-average molecular weight (Mn) of component (B) is preferably 1000 or more, and more preferably 1500 or more. The number-average molecular weight (Mn) of component (B) is preferably 20000 or less, and more preferably 15000 or less. When the number-average molecular weight (Mn) of component (B) is within the above range, component (B) can be adsorbed onto the film on the surface of the silicon wafer, making it easier to inhibit corrosion, and can also be easily removed in the cleaning process after processing, and may not remain on the surface of the workpiece, thus reducing the occurrence of defects.

[0030] The above number-average molecular weight (Mn) is a pullulan-based value and can be measured using gel permeation chromatography with Waters e2695 (column type "TSKgel α-M 13 μm 7.8 mm × 300 mm") and an eluent of "10 mM borate / acetonitrile = 80 / 20".

[0031] In such a semiconductor processing composition, the content (MB) of component (B) is preferably 0.0001 parts by mass or more, more preferably 0.0002 parts by mass or more, even more preferably 0.0005 parts by mass or more, and particularly preferably 0.001 parts by mass or more, when the total mass of the semiconductor processing composition is 100 parts by mass. The content of component (B) is preferably 0.3 parts by mass or less, more preferably 0.2 parts by mass or less, even more preferably 0.15 parts by mass or less, and particularly preferably 0.1 parts by mass or less, when the total mass of the semiconductor processing composition is 100 parts by mass. When the content of component (B) is within the above range, these compounds are adsorbed onto the surface of the workpiece together with component (A), and the occurrence of corrosion can be reduced. Furthermore, by the semiconductor processing composition containing component (B), it is possible to suppress excessive adsorption and residue of component (A) on the surface of the workpiece, and the occurrence of defects can be reduced.

[0032] 1.3. Content Ratio of Component (A) to Component (B) In the semiconductor processing composition according to this embodiment, when the content of component (A) is MA [parts by mass] and the content of component (B) is MB [parts by mass], the content ratio of component (A) to component (B) (MA / MB) is 0.1 or more, preferably 0.13 or more, more preferably 0.4 or more, and particularly preferably 1 or more. The value of MA / MB is 1000 or less, preferably 800 or less, more preferably 500 or less, and particularly preferably 300 or less. When the value of MA / MB is within the above range, corrosion of wiring materials such as tungsten due to excessive adsorption of component (A) to the surface to be processed can be suppressed. In addition, the residue of component (A) on the surface of the object to be processed can be suppressed, and the occurrence of defects can be reduced.

[0033] 1.4. Liquid Medium (C) The semiconductor processing composition according to this embodiment contains a liquid medium (C) as its main component. The type of liquid medium (C) can be appropriately selected according to the intended use of the semiconductor processing composition, such as polishing, cleaning, etching, and resist stripping of the workpiece.

[0034] When the semiconductor processing composition according to this embodiment is used as a CMP slurry or cleaning agent, the liquid medium (C) is preferably an aqueous medium mainly composed of water. Examples of such aqueous media include water, a mixed medium of water and alcohol, and a mixed medium containing water and an organic solvent that is compatible with water. Among these aqueous media, it is preferable to use a mixed medium of water, water and alcohol, and more preferably to use water.

[0035] When the semiconductor processing composition according to this embodiment is used as an etching agent or a resist stripping agent, the liquid medium (C) is preferably a non-aqueous medium mainly composed of an organic solvent. Examples of such non-aqueous media include polar solvents such as ketone solvents, ester solvents, ether solvents, and amide solvents, as well as known organic solvents that can be used in semiconductor processing steps, such as hydrocarbon solvents.

[0036] Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methyl naphthyl ketone, isophorone, and the like.

[0037] Examples of ester solvents include, as chain-like ester solvents, methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, pentyl acetate, isopentyl acetate, ethyl methoxyethyl acetate, ethoxyethyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol Monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol Examples include methyl diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, etc. Examples of cyclic ester solvents include propylene carbonate and lactones such as γ-butyrolactone.

[0038] As the ether-based solvent, for example, glycol ether-based solvents such as ethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether; diisopentyl ether, diisobutyl ether, dioxane, tetrahydrofuran, anisole, perfluoro-2-butyltetrahydrofuran, perfluorotetrahydrofuran, 1,4-dioxane and the like can be mentioned.

[0039] As the amide-based solvent, for example, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidinone and the like can be mentioned. As the other polar solvents described above, dimethyl sulfoxide and the like can be mentioned.

[0040] As the hydrocarbon-based solvent, for example, aliphatic hydrocarbon-based solvents such as pentane, hexane, octane, decane, 2,2,4-trimethylpentane, 2,2,3-trimethylhexane, perfluorohexane, perfluoroheptane, limonene, pinene; aromatic hydrocarbon-based solvents such as toluene, xylene, ethylbenzene, propylbenzene, 1-methylpropylbenzene, 2-methylpropylbenzene, dimethylbenzene, diethylbenzene, ethylmethylbenzene, trimethylbenzene, ethyldimethylbenzene, dipropylbenzene and the like can be mentioned.

[0041] 1.5. pH of the composition for semiconductor processing The pH of the composition for semiconductor processing according to this embodiment is 2 or more, preferably 2.1 or more, more preferably 2.5 or more, and particularly preferably 3 or more. Also, the pH of the composition for semiconductor processing according to this embodiment is 9 or less, preferably 8 or less, more preferably 8.5 or less, and particularly preferably 8 or less. When the pH of the composition for semiconductor processing according to this embodiment is within the above range, corrosion and generation of defects in the wiring material on the surface of the object to be processed can be effectively reduced.

[0042] After mixing each component to prepare a composition for semiconductor processing, if the desired pH cannot be obtained, a pH adjuster described below may be separately added to adjust the pH within the above range.

[0043] In the present invention, pH refers to the hydrogen ion exponent, and its value can be measured using a commercially available pH meter (for example, a desktop pH meter manufactured by Horiba, Ltd.) under the conditions of 25 °C and 1 atm.

[0044] 1.6. Other Components The composition for semiconductor processing according to this embodiment may contain necessary components as appropriate according to the purpose of use of the composition for semiconductor processing such as polishing, cleaning, etching, resist stripping, etc., in addition to the above-described components. Examples of such components include abrasive grains, pH adjusters, amines, water-soluble polymers, surfactants, and the like.

[0045] 1.6.1. Abrasive Grains When the composition for semiconductor processing according to this embodiment is used as a CMP slurry, it is preferable to contain abrasive grains. Examples of the abrasive grains include inorganic particles such as silica, ceria, alumina, zirconia, and titania. Among these, silica particles are preferable.

[0046] Examples of the silica particles include colloidal silica and fumed silica. Among these, colloidal silica is preferable. Colloidal silica is preferably used from the viewpoint of reducing polishing defects such as scratches. As the colloidal silica, those produced by the methods described in, for example, JP-A-2003-109921 can be used. Further, colloidal silica surface-modified by the methods described in JP-A-2010-269985, J. Ind.Eng.Chem., Vol.12, No.6, (2006) 911-917, etc. may also be used.

[0047] The semiconductor processing composition according to this embodiment can be prepared by diluting the stock solution composition with a liquid medium, or the stock solution composition can be used as is as the semiconductor processing composition. In such a semiconductor processing composition, the abrasive content is preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more, when the total mass of the semiconductor processing composition (CMP slurry) used on the workpiece is 100 parts by mass. Furthermore, the abrasive content is preferably 10 parts by mass or less, and more preferably 6 parts by mass or less, when the total mass of the semiconductor processing composition (CMP slurry) is 100 parts by mass. When the abrasive content is within the above range, a practical polishing speed can be obtained for the workpiece.

[0048] 1.6.2. pH Adjusting Agents The semiconductor processing compositions according to this embodiment may contain pH adjusting agents to adjust the pH to a desired level, regardless of the intended use of the semiconductor processing composition. In this specification, "pH adjusting agent" is a concept that does not include water-soluble polymers, as described later.

[0049] Examples of pH adjusting agents include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; organic acids having one or more acidic functional groups such as carboxyl groups or sulfo groups; alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide; organic ammonium salts such as tetramethylammonium hydroxide; and basic compounds such as ammonia. These pH adjusting agents may be used individually or in mixtures of two or more.

[0050] Among organic acids, compounds represented by the following general formula (1) are preferred because they have the effect of adjusting the pH and reducing or removing contamination on the surface of the object being treated.

[0051] (In the above general formula (1), R １ (This represents an organic group with 1 to 20 carbon atoms.)

[0052] In the above general formula (1), R １Examples of C1-C20 organic groups in this context include C1-C20 aliphatic saturated hydrocarbon groups, C1-C20 aliphatic unsaturated hydrocarbon groups, C6-C20 organic groups having a cyclic saturated hydrocarbon group, C6-C20 organic groups having a cyclic unsaturated hydrocarbon group, C1-C20 hydrocarbon groups having a carboxyl group, C1-C20 hydrocarbon groups having a hydroxyl group, C1-C20 hydrocarbon groups having both a carboxyl and a hydroxyl group, C1-C20 hydrocarbon groups having an amino group, C1-C20 hydrocarbon groups having both an amino and a carboxyl group, and C1-C20 organic groups having a heterocyclic group. Among these, C1-C20 aliphatic saturated hydrocarbon groups, C6-C20 cyclic unsaturated hydrocarbon groups, or C1-C20 hydrocarbon groups having a carboxyl group are preferred, and C6-C20 organic groups having an aryl group or a carboxymethyl group are particularly preferred.

[0053] Specific examples of compounds represented by the above general formula (1) include citric acid, malonic acid, maleic acid, tartaric acid, malic acid, succinic acid, phthalic acid, glutamic acid, aspartic acid, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, and iminodiacetic acid. Among these, at least one selected from the group consisting of citric acid, malonic acid, maleic acid, tartaric acid, malic acid, and succinic acid is preferred, at least one selected from the group consisting of citric acid, malonic acid, and malic acid is more preferred, and citric acid or malonic acid is particularly preferred. By including such organic acids, contamination of the surface of the object to be treated can be particularly reduced or removed. The compounds exemplified above may be used individually or in combination of two or more.

[0054] When using the semiconductor processing composition according to this embodiment as a cleaning agent, the content ratio of organic acids can be appropriately changed depending on the materials exposed on the surface of the workpiece after CMP, such as wiring materials like tungsten, insulating materials like silicon oxide, and barrier metal materials like tantalum nitride and titanium nitride, as well as the composition of the CMP slurry used.

[0055] Furthermore, when preparing a semiconductor processing composition by diluting the stock solution composition (concentrated type) in a liquid medium, the organic acid content can be appropriately changed depending on the degree of dilution. The organic acid content is preferably 0.0001 parts by mass or more and 1 part by mass or less, and more preferably 0.0005 parts by mass or more and 0.5 parts by mass or less, when the total mass of the semiconductor processing composition prepared by diluting the stock solution composition (concentrated type) or the stock solution composition (undiluted type) is 100 parts by mass. When the organic acid content is within the above range, impurities adhering to the surface of the wiring material can be removed more effectively. Also, excessive etching can be suppressed more effectively, and a good processed workpiece can be obtained.

[0056] 1.6.3. Amines When using the semiconductor processing composition according to this embodiment as a cleaning agent, it is preferable that it contains amines. Amines have the function of an etching agent. Therefore, by adding amines, in the cleaning step after the completion of CMP, the metal oxide film on the wiring substrate (e.g., CuO, Cu) is removed. ２ O and Cu(OH) ２ It is thought that the layers (and organic residues, such as the BTA layer) can be removed by etching.

[0057] The amine used in the detergent is preferably a water-soluble amine. The definition of "water-soluble" is as described above, meaning that the amount that dissolves in 100 g of water at 20°C is 0.1 g or more. Examples of amines include alkanolamines, primary amines, secondary amines, and tertiary amines.

[0058] Examples of alkanolamines include monoethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, N-methyl-N,N-diethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N-dibutylethanolamine, N-(β-aminoethyl)ethanolamine, N-ethylethanolamine, monopropanolamine, dipropanolamine, trippropanolamine, monoisopropanolamine, diisopropanolamine, and triisopropanolamine. Examples of primary amines include methylamine, ethylamine, propylamine, butylamine, pentylamine, and 1,3-propanediamine. Examples of secondary amines include piperidine and piperazine. Examples of tertiary amines include trimethylamine and triethylamine. These amines may be used individually or in combination of two or more.

[0059] Among these amines, monoethanolamine and monoisopropanolamine are preferred, with monoethanolamine being more preferred, due to their high effectiveness in etching metal oxide films and organic residues on the wiring substrate.

[0060] When using the semiconductor processing composition according to this embodiment as a cleaning agent, the amine content can be appropriately changed depending on the materials exposed on the surface of the workpiece after CMP, such as wiring materials like tungsten, insulating materials like silicon oxide, and barrier metal materials like tantalum nitride and titanium nitride, as well as the composition of the CMP slurry used.

[0061] Furthermore, when preparing a semiconductor processing composition by diluting the stock solution composition (concentrated type) in a liquid medium, the amine content can be appropriately changed depending on the degree of dilution. The amine content is preferably 0.0001 parts by mass or more and 1 part by mass or less, and more preferably 0.0005 parts by mass or more and 0.5 parts by mass or less, when the total mass of the semiconductor processing composition prepared by diluting the stock solution composition (concentrated type) or the stock solution composition (undiluted type) is 100 parts by mass. When the amine content is within the above range, metal oxide films and organic residues on the wiring substrate can be more effectively etched and removed in the cleaning step after the completion of CMP.

[0062] 1.6.4. Surfactants The semiconductor processing compositions according to this embodiment may contain surfactants other than component (B), regardless of the intended use of the semiconductor processing composition. Nonionic surfactants or anionic surfactants can be preferably used as surfactants. By including surfactants, the effect of removing particles and metal impurities contained in the CMP slurry from the wiring substrate is enhanced, and a better surface of the workpiece may be obtained.

[0063] Examples of nonionic surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene aryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, and sorbitan monostearate; and polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, and polyoxyethylene sorbitan monostearate. The nonionic surfactants exemplified above may be used individually or in combination of two or more.

[0064] Examples of anionic surfactants include alkylbenzenesulfonic acids such as dodecylbenzenesulfonic acid; alkylnaphthalenesulfonic acid; alkyl sulfate esters such as lauryl sulfate; sulfate esters of polyoxyethylene alkyl ethers such as polyoxyethylene lauryl sulfate; naphthalenesulfonic acid condensates; alkyliminodicarboxylic acids; and ligninsulfonic acid. These anionic surfactants may also be used in the form of salts. In this case, examples of countercations include sodium ions, potassium ions, and ammonium ions, but ammonium ions are preferred from the viewpoint of preventing the presence of excess potassium or sodium.

[0065] In CMP (Computerized Multilayer) treatment of workpieces containing tungsten as a wiring material, a CMP slurry containing iron ions and peroxides (such as hydrogen peroxide and potassium iodate) may be used. Since the iron ions contained in this CMP slurry are easily adsorbed onto the surface of the workpiece, the surface of the workpiece is prone to iron contamination. In this case, since iron ions are positively charged, adding an anionic surfactant to the semiconductor treatment composition may effectively remove the iron contamination from the surface of the workpiece.

[0066] The surfactant content can be appropriately adjusted depending on the materials exposed on the surface of the workpiece after CMP, such as wiring materials like tungsten, insulating materials like silicon oxide, and barrier metal materials like tantalum nitride and titanium nitride, as well as the composition of the CMP slurry used.

[0067] Furthermore, when preparing a semiconductor processing composition by diluting the stock solution composition (concentrated type) in a liquid medium, the surfactant content can be appropriately changed depending on the degree of dilution. The surfactant content is preferably 0.001 parts by mass or more and 1 part by mass or less, and more preferably 0.005 parts by mass or more and 0.5 parts by mass or less, when the total mass of the semiconductor processing composition prepared by diluting the stock solution composition (concentrated type) or the stock solution composition (undiluted type) is 100 parts by mass. When the surfactant content is within the above range, the effect of removing particles and metal impurities contained in the CMP slurry from the wiring substrate is enhanced, and a better surface of the workpiece may be obtained.

[0068] 1.6.5. Water-soluble polymers The semiconductor processing compositions according to this embodiment may contain water-soluble polymers different from component (B), regardless of the intended use of the semiconductor processing composition. By containing water-soluble polymers, the water-soluble polymers are adsorbed onto the surface of the object to be processed to form a film, which may further reduce corrosion of the object to be processed. The definition of "water-soluble" is as described above, meaning that the mass that dissolves in 100 g of water at 20°C is 0.1 g or more.

[0069] Examples of water-soluble polymers include, but are not limited to, polyacrylic acid, polymethacrylic acid, polymaleic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, polystyrene sulfonic acid, and salts thereof; copolymers of monomers such as styrene, α-methylstyrene, and 4-methylstyrene with acid monomers such as (meth)acrylic acid and maleic acid, and polymers having repeating units with aromatic hydrocarbon groups obtained by condensing benzenesulfonic acid, naphthalene sulfonic acid, etc. with formalin, and salts thereof; vinyl-based synthetic polymers such as polyvinyl alcohol and polyoxyethylene; and modified natural polysaccharides such as hydroxyethylcellulose, carboxymethylcellulose, and modified starch. These water-soluble polymers can be used individually or in combination of two or more.

[0070] The number-average molecular weight (Mn) of the water-soluble polymer is preferably 1,000 to 15,000, more preferably 3,000 to 10,000. This "number-average molecular weight (Mn)" is a pullulan-based value and can be measured using gel permeation chromatography Waters e2695 (column type "TSKgel α-M 13 μm 7.8 mm × 300 mm") with an eluent of "10 mM borate / acetonitrile = 80 / 20".

[0071] The content of the water-soluble polymer should be adjusted so that the viscosity of the semiconductor processing composition at 25°C is 2 mPa·s or less. If the viscosity of the semiconductor processing composition at 25°C exceeds 2 mPa·s, the viscosity may become too high, making it difficult to stably supply the semiconductor processing composition to the material to be processed. The viscosity of the semiconductor processing composition is affected by the number-average molecular weight and content of the added water-soluble polymer, so it is best to adjust it while considering the balance of these factors.

[0072] When using the semiconductor processing composition according to this embodiment as a cleaning agent, the content ratio of the water-soluble polymer can be appropriately changed depending on the materials exposed on the surface of the workpiece after CMP, such as wiring materials like tungsten, insulating materials like silicon oxide, and barrier metal materials like tantalum nitride and titanium nitride, as well as the composition of the CMP slurry used.

[0073] Furthermore, when using the semiconductor processing composition according to this embodiment as a cleaning agent, the content ratio of the water-soluble polymer can be appropriately changed depending on the degree of dilution when preparing the semiconductor processing composition by diluting the stock solution composition (concentrated type). The content ratio of the water-soluble polymer is preferably 0.001 parts by mass or more and 1 part by mass or less, and more preferably 0.01 parts by mass or more and 0.1 parts by mass or less, when the total mass of the semiconductor processing composition prepared by diluting the stock solution composition (concentrated type) or the stock solution composition (undiluted type) is 100 parts by mass. When the content ratio of the water-soluble polymer is within the above range, it is easier to achieve both corrosion suppression and removal of particles and metal impurities contained in the CMP slurry from the wiring substrate, and a better processed object can be obtained.

[0074] 1.7. Method for preparing the stock solution composition The stock solution composition is not particularly limited and can be prepared using known methods. Specifically, it can be prepared by dissolving each of the above-mentioned components in a liquid medium such as water or an organic solvent and then filtering. There are no particular restrictions on the mixing order or mixing method of each of the above-mentioned components.

[0075] When preparing the stock solution composition, it is preferable to control the particle size by filtering with a depth-type or pleated-type filter as needed. Here, a depth-type filter is a high-precision filtration filter also called a deep-layer filtration or volumetric filtration type filter. Such depth-type filters include those with a laminated structure in which filtration membranes with many pores are stacked, and those made by winding up fiber bundles. Specific examples of depth-type filters include Profile II, Nexis NXA, Nexis NXT, Polyfine XLD, UltiPleated Profile, etc. (all manufactured by Nippon Pall Co., Ltd.), Depth Cartridge Filter, Wind Cartridge Filter, etc. (all manufactured by Advantec Co., Ltd.), CP Filter, BM Filter, etc. (all manufactured by Chisso Corporation), Slope Pure, Dia, Microcilia, etc. (all manufactured by Rokitechno Co., Ltd.).

[0076] Examples of pleated filters include cylindrical high-precision filtration filters obtained by folding a precision filtration membrane sheet made of nonwoven fabric, filter paper, metal mesh, etc., into pleats, forming it into a cylindrical shape, sealing the seams of the pleats of the sheet liquid-tight, and sealing both ends of the cylinder liquid-tight. Specifically, examples include HDCII, Polyfine II, etc. (all manufactured by Nippon Pall Co., Ltd.), PP pleated cartridge filter (manufactured by Advantec Co., Ltd.), Porous Fine (manufactured by Chisso Corporation), Sartonpore, Micropure, etc. (all manufactured by Rokitechno Co., Ltd.).

[0077] 1.8. Composition for semiconductor processing The semiconductor processing composition according to this embodiment can be prepared by diluting the stock solution composition (concentrated type) in a liquid medium, or the stock solution composition (undiluted type) can be used as is as a semiconductor processing composition. The semiconductor processing composition can then be used as a CMP slurry for chemical mechanical polishing, a cleaning agent for cleaning semiconductor surfaces, a resist stripping agent, or an etching agent.

[0078] Here, the liquid medium used for dilution is synonymous with the liquid medium (C) contained in the stock solution composition described above, and can be appropriately selected from the liquid mediums (C) exemplified above depending on the type of semiconductor processing composition.

[0079] One method for diluting a stock solution composition by adding a liquid medium involves merging the piping supplying the stock solution composition and the piping supplying the liquid medium midway through the process to mix them, and then supplying this mixed semiconductor processing composition to the surface of the object to be processed. This mixing can be carried out using commonly used methods such as: a method of mixing liquids by collision through a narrow passage under pressure; a method of repeatedly separating, diverting, and merging the liquid flow by filling the piping with packing materials such as glass tubes; or a method of installing power-driven rotating blades in the piping.

[0080] Another method for diluting the stock solution composition by adding a liquid medium involves providing separate piping for supplying the stock solution composition and piping for supplying the liquid medium, supplying a predetermined amount of liquid from each to the surface of the object to be treated, and mixing them on the surface. Furthermore, another method for diluting the stock solution composition by adding a liquid medium involves placing a predetermined amount of stock solution composition and a predetermined amount of liquid medium in a single container, mixing them, and then supplying the mixed semiconductor processing composition to the surface of the object to be treated.

[0081] When diluting the stock solution composition by adding a liquid medium, it is preferable to dilute 1 part by mass of the stock solution composition to 1 to 500 parts by mass (1 to 500 times), more preferably to 20 to 500 parts by mass (20 to 500 times), and particularly preferably to 30 to 300 parts by mass (30 to 300 times). It is preferable to dilute with the same liquid medium contained in the stock solution composition as described above. By concentrating the stock solution composition in this way, it becomes possible to transport and store it in smaller containers compared to transporting and storing the semiconductor processing composition as is. As a result, transportation and storage costs can be reduced. In addition, since a smaller amount of stock solution composition is purified compared to purifying the semiconductor processing composition by filtration, etc., the purification time can be shortened, thereby enabling mass production.

[0082] 2. Processing Method A processing method according to one embodiment of the present invention includes a step of processing using the semiconductor processing composition described above. In the processing method according to this embodiment, "processing" means polishing the surface of the object to be processed when the semiconductor processing composition is a CMP slurry, cleaning the surface of the object to be processed after the completion of CMP to remove particles, metal impurities, etc. when the semiconductor processing composition is a cleaning agent, peeling the resist from the surface of the object to be processed using the resist when the semiconductor processing composition is a resist stripper, and lightly etching the surface of wiring material, etc. to remove surface contamination when the semiconductor processing composition is an etching agent.

[0083] One embodiment of the processing method according to this embodiment includes a step of polishing a wiring substrate containing tungsten or the like as a wiring material using the above-mentioned semiconductor processing composition (CMP slurry). Another embodiment of the processing method according to this embodiment includes a step of chemically and mechanically polishing the wiring substrate containing tungsten or the like as a wiring material, and then cleaning it using the above-mentioned semiconductor processing composition (cleaning agent). Hereinafter, an example of the processing method according to this embodiment will be described in detail with reference to the drawings.

[0084] 2.1. Object to be processed Figure 1 shows an example of an object to be processed 100 that can be applied to the processing method according to this embodiment.

[0085] (1) First, prepare a substrate 10 as shown in Figure 1. The substrate 10 may be composed of, for example, a silicon substrate and a silicon oxide film formed thereon. Furthermore, functional devices such as transistors may be formed on the substrate 10.

[0086] (2) Next, a silicon oxide film 12, which is an insulating film, is formed on the substrate 10 by a CVD method using silane gas and oxygen gas. After that, the silicon oxide film 12 is polished partially by CMP to flatten the surface.

[0087] (3) Next, a resist pattern is formed on the silicon oxide film 12. Using this as a mask, the silicon oxide film 12 is etched to form contact holes 14. After forming the contact holes 14, the resist pattern is removed.

[0088] (4) Next, the CVD method is applied to deposit the tungsten film 16 on the surface of the silicon oxide film 12 and inside the contact holes 14.

[0089] Through the above steps, the workpiece 100 is formed.

[0090] 2.2. Polishing Process In the polishing process, as shown in Figure 2, the tungsten film 16 is chemically and mechanically polished using the semiconductor processing composition (CMP slurry) described above until the silicon oxide film 12 is exposed. The CMP slurry described above allows for a high polishing speed of the tungsten film and reduces corrosion and defects on the tungsten surface, thus enabling the formation of a tungsten plug of good quality.

[0091] After the polishing process, any abrasive particles remaining on the surface of the workpiece are removed. This removal of abrasive particles can be carried out by conventional cleaning methods. For example, after brush scrubbing, the abrasive particles adhering to the surface of the workpiece can be removed by cleaning with the aforementioned semiconductor processing composition (cleaning agent) or an alkaline cleaning solution in a ratio of approximately 1:1:5 (mass ratio) of ammonia:hydrogen peroxide:water. Furthermore, as a cleaning solution for impurity metal species adsorbed on the surface of the workpiece, for example, the aforementioned semiconductor processing composition (cleaning agent), citric acid aqueous solution, a mixed aqueous solution of hydrofluoric acid and citric acid, and a mixed aqueous solution of hydrofluoric acid and ethylenediaminetetraacetic acid (EDTA) can be used.

[0092] 2.3. Cleaning Process In the cleaning process, the surface of the workpiece 100 shown in Figure 2 is treated with the semiconductor processing composition (cleaning agent) described above. By using the semiconductor processing composition (cleaning agent) described above, corrosion of the wiring material and barrier metal material after CMP is suppressed, and contamination can be effectively removed from the surface of the workpiece.

[0093] Furthermore, it is highly effective to chemically and mechanically polish a wiring substrate containing tungsten as a wiring material using a composition containing iron ions and peroxides (Fenton's reagent) as described in Japanese Patent Publication No. 10-265766, etc., and then perform a cleaning step using the above-mentioned semiconductor processing composition (cleaning agent). In CMP of a workpiece having tungsten as a wiring material, a CMP slurry containing iron ions and peroxides (hydrogen peroxide, potassium iodate, etc.) as a highly oxidizing agent is sometimes used. Since the iron ions contained in this CMP slurry are easily adsorbed onto the surface of the workpiece, the surface of the workpiece is prone to iron contamination. In this case, iron contamination can be removed by treating the surface of the workpiece with dilute hydrofluoric acid, but the surface of the workpiece is etched and becomes susceptible to corrosion. However, by performing a cleaning step using the above-mentioned semiconductor processing composition, iron ions and other substances present on the surface of the workpiece after CMP are encapsulated and removed in the hydrophobic cavities inside the cyclic structure of component (A), and the metals such as metal wiring materials can be made less susceptible to corrosion by the action of component (B).

[0094] The cleaning method is not particularly limited, but is carried out by directly contacting the workpiece 100 with the semiconductor processing composition (cleaning agent) described above. Methods for directly contacting the workpiece 100 with the cleaning agent include a dip method in which a cleaning tank is filled with cleaning agent and the wiring board is immersed; a spin method in which the wiring board is rotated at high speed while the cleaning agent flows down onto the wiring board from a nozzle; and a spray method in which the cleaning agent is sprayed onto the wiring board for cleaning. Apparatus for carrying out such methods includes a batch processing apparatus that processes multiple wiring boards contained in a cassette simultaneously, and a single-wafer processing apparatus that processes one wiring board mounted in a holder.

[0095] In the cleaning process, the temperature of the cleaning agent is usually room temperature, but it may be heated to a range that does not impair its performance, for example, to about 40-70°C.

[0096] Furthermore, in addition to the method of directly contacting the object to be treated 100 with the cleaning agent described above, it is also preferable to use a treatment method that utilizes physical force. This improves the removal of contamination by particles adhering to the object to be treated 100 and shortens the treatment time. Examples of treatment methods that utilize physical force include scrubbing with a cleaning brush and ultrasonic cleaning.

[0097] Furthermore, washing with ultrapure water or pure water may be performed before and / or after the washing process.

[0098] 2.4. Semiconductor Processing Apparatus In the step of performing chemical mechanical polishing using the above-described semiconductor processing composition, for example, a semiconductor processing apparatus 200 as shown in Figure 3 can be used. Figure 3 is a schematic perspective view of the semiconductor processing apparatus 200. The process is carried out by supplying the semiconductor processing composition (CMP slurry) 44 from a slurry supply nozzle 42 and rotating a turntable 48 to which a polishing pad 46 is attached, while bringing a carrier head 52 holding a semiconductor substrate 50 into contact with it. A water supply nozzle 54 and a dresser 56 are also shown in Figure 3.

[0099] The processing load of the carrier head 52 can be selected within the range of 10 to 980 hPa, preferably 30 to 490 hPa. The rotational speed of the turntable 48 and the carrier head 52 can be appropriately selected within the range of 10 to 400 rpm, preferably 30 to 150 rpm. The flow rate of the slurry (CMP slurry) 44 supplied from the slurry supply nozzle 42 can be selected within the range of 10 to 1,000 mL / min, preferably 50 to 400 mL / min.

[0100] Examples of commercially available semiconductor processing equipment include models "EPO-112," "EPO-222," and "F-REX300SII" from Ebara Corporation; models "LGP-510" and "LGP-552" from Lappmaster SFT Corporation; models "Mirra" and "Reflexion" from Applied Materials Corporation; and model "POLI-762" from G&P Technology Corporation.

[0101] 3. Examples The present invention will be described below with reference to examples, but the present invention is not limited in any way by these examples. In these examples, "parts" and "%" are based on mass unless otherwise specified.

[0102] 3.1. Examples 1-11, Comparative Examples 1-10 3.1.1. Preparation of the stock solution composition and semiconductor processing composition (CMP slurry) The stock solution compositions described in Examples 1-11 and Comparative Examples 1-10 were obtained by adding components (A), (B), abrasive grains, other components, pH adjuster, and deionized water shown in Table 1 or Table 2 below to a polyethylene container and stirring for 15 minutes. In Tables 1 and 2 below, the numerical values ​​for the content of each component represent parts by mass. In each example and comparative example, the total content of each component was 100 parts by mass, and the remaining amount after adjusting the pH with the pH adjuster was deionized water.

[0103] 3.1.2. Corrosion Evaluation As shown in Figure 4, a patterned wafer "MASK754 W PTW" from Advance Materials Technology Co., Ltd. with a diameter of 12 inches was prepared. In the patterned wafer 300 shown in Figure 4, 62 is "300 mm Si" and 64 is "100 nm PE-TEOS (SiO２ ) , 66 represents "10nm Ti", 68 represents "6nm TiN", and 70 represents "200nm W". Using this patterned wafer 300 as the workpiece, the first stage of chemical mechanical polishing was performed under the following conditions.

[0104] <First Stage Polishing Conditions> • Polishing device: Applied Materials, Model "REFLEXION LK" • Chemical mechanical polishing composition: Entegris (Cabot Microelectronics), "W2000" (slurry containing iron ions and hydrogen peroxide) • Polishing pad: Rodel Nitta, "IC1000 / SUBA400" • Plate rotation speed: 70 rpm • Head rotation speed: 71 rpm • Head pressure: 3 psi • Chemical mechanical polishing composition supply rate: 200 mL / min • Polishing time: 150 seconds

[0105] Next, the stock solution composition described in Table 1 or Table 2 below was added to a 10 L polyethylene bottle, and deionized water was added to achieve the dilution ratio described in Table 1 or Table 2 below to prepare a semiconductor processing composition (CMP slurry). Using the semiconductor processing composition (CMP slurry) prepared in this way, a second stage of chemical mechanical polishing was performed on the polished surface obtained in the first stage of chemical mechanical polishing under the following polishing conditions.

[0106] <Second Stage Polishing Conditions> ・Polishing device: Applied Materials, model "REFLEXION LK" ・Polishing pad: Fuji Spinning Co., Ltd., "Porous polyurethane pad; H800-type1 (3-1S) 775" ・Semiconductor processing composition (CMP slurry) supply rate: 300 mL / min ・Plate rotation speed: 100 rpm ・Head rotation speed: 90 rpm ・Head pressing pressure: 2 psi

[0107] The patterned wafers, after the second stage of chemical mechanical polishing described above, were cleaned in a cleaning module using Fujifilm Wako Pure Chemical Industries' "CLEAN-100". Afterwards, the surface of the treated material was observed with an SEM. The evaluation criteria are as follows: (Evaluation Criteria) ・A: If there are 3 or fewer corrosion spots in the 100k field of view, it is judged to be very good, as sufficient corrosion suppression is possible in actual semiconductor polishing. ・B: If there are 4 to 6 corrosion spots in the 100k field of view, it is judged to be good, as the corrosion is within an acceptable range. ・C: If there are 7 or more corrosion spots in the 100k field of view, it is judged to be poor, as corrosion suppression is difficult.

[0108] 3.1.3. Defect Evaluation The patterned wafers after the corrosion evaluation described above were observed using a defect inspection device (KLA2351, manufactured by KLA-Tencor). The number of defects was calculated by measuring the pixel size of the defect inspection device at 0.16 μm in array mode and detecting and evaluating defects extracted from the differences resulting from the superposition of the comparison image and the pixel unit. The evaluation criteria are as follows: (Evaluation Criteria) ・A: If there are 5 or fewer defects of 0.16 μm or larger per wafer, it is judged to be a good result. ・B: If there are 6 to 10 defects of 0.16 μm or larger per wafer, it is judged to be acceptable. ・C: If there are 11 or more defects of 0.16 μm or larger per wafer, it is judged to be a defective product because there is a concern that abnormalities may occur in the electrical characteristics of the wafer.

[0109] 3.1.4. Stability Evaluation The particle size of the particles contained in the semiconductor processing composition (CMP slurry) obtained by diluting the stock solution composition immediately after preparation as described above was measured using a nanoparticle analyzer (Horiba, Ltd., model number "SZ-100"). Furthermore, 500 g of the stock solution composition immediately after preparation was added to a colorless, transparent glass container and left to stand in a constant temperature storage chamber at 60°C for one week. The particle size of the particles contained in the semiconductor processing composition (CMP slurry) obtained by diluting the stock solution composition after storage was measured using a nanoparticle analyzer (Horiba, Ltd., model number "SZ-100"). The particle size change rate was calculated according to the following formula. The evaluation criteria are as follows. Particle size change rate (%) = (Particle size (nm) of particles contained in the semiconductor processing composition (CMP slurry) obtained by diluting the stock solution composition after storage) / (Particle size (nm) of particles contained in the semiconductor processing composition (CMP slurry) obtained by diluting the stock solution composition immediately after preparation) × 100 (Evaluation criteria) ・A: The particle size change rate is less than 105%, and the aggregation of abrasive grains after storage is slight, so the polishing characteristics remain unchanged even after storage and stable polishing characteristics are exhibited, which is judged to be very good. ・B: The particle size change rate is 105% or more and less than 110%, and the polishing characteristics do not change significantly due to the aggregation of abrasive grains after storage, so it is judged to be good and can be used in practice. ・C: The particle size change rate is 110% or more, and the aggregation of abrasive grains after storage is severe, so the polishing characteristics change significantly, so it is judged to be poor and cannot be used in practice.

[0110] 3.1.5. Evaluation Results Tables 1 and 2 below show the composition of the stock solution composition and the semiconductor processing composition (CMP slurry) obtained from the stock solution composition, as well as the evaluation results.

[0111]

[0112]

[0113] The following provides supplementary information to the explanations of each component in Tables 1 and 2 above. <(A) Component> ・Isothiazole: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "Isothiazole" ・Benzothiazole: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "Benzothiazole" ・2-Benzothiazolethiol: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "2-Benzothiazolethiol" ・2-Mercapto-2-thiazoline: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "2-Mercapto-2-thiazoline" ・2-Methyl-4-isothiazoline-3-one: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "2-Methyl-4-isothiazoline-3-one" ・5-Chloro-2-methyl-3-isothiazolon: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "5-Chloro-2-methyl-3-isothiazolon" • 2-n-octyl-4-isothiazolin-3-one: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "2-n-octyl-4-isothiazolin-3-one" • 1,2-benzoisothiazole-3(2H)-one: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "1,2-Benzisothiazole-3(2H)-one <(B) Components> ・Polyhexamethylene biguanide: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Poly(hexamethylene biguanide) hydrochloride" ・Polylysine: Manufactured by JNC Corporation, product name "ε-Poly-L-Lysine" ・Polyallylamine A: Manufactured by Nitto Boseki Co., Ltd., product name "PAA-03", Mn=3000 ・Polyallylamine B: Manufactured by Nitto Boseki Co., Ltd., product name "PAA-05", Mn=5000 ・Polyallylamine C: Manufactured by Nitto Boseki Co., Ltd., product name "PAA-08", Mn=8000 ・Polyethyleneimine: Manufactured by Nippon Shokubai Co., Ltd., product name "Epomin" SP-200, Mn=10000 <Abrasive grains> ・PL-3: Manufactured by Fuso Chemical Industries, Ltd., product name "PL-3", colloidal silica, average secondary particle size 70 nm ・GEN4-H: Manufactured by Saint-Gobain, product name "GEN4-H", colloidal alumina, average secondary particle size 100 nm <Others> ・Polyacrylic acid: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Polyacrylic acid 5000", Mn=5000 ・Polyethylene glycol: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Polyethylene glycol 20000", Mn=20000 <pH adjusters> ・Acetic acid: Manufactured by Kanto Chemical Co., Ltd., product name "EL-UM Acetic acid" ・Sulfuric acid: Manufactured by Kanto Chemical Co., Ltd., product name "EL-UM Sulfuric acid" ・Citric acid: Manufactured by Hayashi Pure Chemical Industries, Ltd., product name "Citric acid (crystal)" ・Phosphoric acid: Manufactured by Rasa Industries, Ltd., product name "Phosphoric acid" - Maleic acid: Manufactured by Fuso Chemical Industry Co., Ltd., product name "Hydrated Maleic Acid" - Potassium hydroxide: Manufactured by Kanto Chemical Co., Ltd., product name "KOH (Potassium Hydroxide Aqueous Solution) 48%"

[0114] As shown in Table 1 above, the semiconductor processing compositions (CMP slurries) obtained from the stock solutions of Examples 1 to 11, where the MA / MB was 0.1 to 1000, exhibited good corrosion characteristics for tungsten films on pattern wafers, and also yielded good results in defect evaluation after the CMP process using these compositions. Furthermore, the semiconductor processing compositions (CMP slurries) of Examples 1 to 11 showed no aggregation even after being stored at 60°C for one week, demonstrating excellent stability when stored as stock solutions.

[0115] On the other hand, as shown in Table 2 above, when the semiconductor processing compositions (CMP slurries) of Comparative Examples 1, 2, 4, 8, and 9 did not contain component (B), the corrosion evaluation and / or defect evaluation results were poor. When the semiconductor processing composition (CMP slurry) of Comparative Example 7 did not contain component (A), the corrosion evaluation results were poor. When the pH was outside the range of 2 to 9, as in the semiconductor processing compositions (CMP slurries) of Comparative Examples 2 and 3, the corrosion evaluation results were poor.

[0116] 3.2. Examples 12-22, Comparative Examples 11-19 3.2.1. Preparation of the stock solution composition and semiconductor processing composition (cleaning agent) The stock solution compositions described in Examples 12-22 and Comparative Examples 11-19 were obtained by adding component (A), component (B), other components, pH adjuster, and deionized water shown in Table 3 or Table 4 below to a polyethylene container and stirring for 15 minutes. In Tables 3 and 4 below, the numerical values ​​for the content of each component represent parts by mass. In each example and comparative example, the total content of each component was 100 parts by mass, and the remaining amount after adjusting the pH with the pH adjuster was deionized water.

[0117] 3.2.2. Corrosion Evaluation As shown in Figure 4, a patterned wafer "MASK754 W PTW" from Advance Materials Technology Co., Ltd. with a diameter of 12 inches was prepared. In the patterned wafer 300 shown in Figure 4, 62 is "300 mm Si" and 64 is "100 nm PE-TEOS (SiO ２ ) , 66 represents "10nm Ti", 68 represents "6nm TiN", and 70 represents "200nm W". Using this patterned wafer 300 as the workpiece, the first stage of chemical mechanical polishing was performed under the following conditions.

[0118] <First Stage Polishing Conditions> • Polishing device: Applied Materials, Model "REFLEXION LK" • Chemical mechanical polishing composition: Entegris (Cabot Microelectronics), "W2000" (slurry containing iron ions and hydrogen peroxide) • Polishing pad: Rodel Nitta, "IC1000 / SUBA400" • Plate rotation speed: 70 rpm • Head rotation speed: 71 rpm • Head pressure: 3 psi • Chemical mechanical polishing composition supply rate: 200 mL / min • Polishing time: 150 seconds

[0119] Next, colloidal silica aqueous dispersion PL-3 (manufactured by Fuso Chemical Industry Co., Ltd.) was added to a polyethylene container in an amount equivalent to 1% by mass in terms of silica. Ion-exchanged water and maleic acid as a pH adjuster were added so that the total amount of all components was 100% by mass, the pH was adjusted to 3, and the mixture was stirred for 15 minutes to obtain a CMP slurry. Using the CMP slurry prepared in this way, a second stage of chemical mechanical polishing was performed on the polished surface obtained in the first stage of chemical mechanical polishing under the following polishing conditions.

[0120] <Second Stage Polishing Conditions> ・Polishing device: Applied Materials, model "REFLEXION LK" ・Polishing pad: Fuji Spinning Co., Ltd., "Porous polyurethane pad; H800-type1 (3-1S) 775" ・CMP slurry supply speed: 300 mL / min ・Plate rotation speed: 100 rpm ・Head rotation speed: 90 rpm ・Head pressing pressure: 2 psi

[0121] The patterned wafers, after the second stage of chemical mechanical polishing described above, were cleaned using a semiconductor processing composition (cleaning agent) obtained by diluting the stock solution composition. Subsequently, the surface of the processed material was observed using an SEM. The evaluation criteria are as follows: (Evaluation Criteria) ・A: If there are 3 or fewer corrosion spots in the 100k field of view, it is judged to be very good, as sufficient corrosion suppression is possible in actual semiconductor polishing. ・B: If there are 4 to 6 corrosion spots in the 100k field of view, it is judged to be good, as the corrosion is within an acceptable range. ・C: If there are 7 or more corrosion spots in the 100k field of view, it is judged to be poor, as corrosion suppression is difficult.

[0122] 3.2.3. Defect Evaluation The patterned wafers after the corrosion evaluation described above were observed using a defect inspection device (KLA2351, manufactured by KLA-Tencor). The number of defects was calculated by measuring the pixel size of the defect inspection device at 0.16 μm in array mode and detecting and evaluating defects extracted from the differences resulting from the superposition of the comparison image and the pixel unit. The evaluation criteria are as follows: (Evaluation Criteria) ・A: If there are 5 or fewer defects of 0.16 μm or larger per wafer, it is judged to be a good result. ・B: If there are 6 to 10 defects of 0.16 μm or larger per wafer, it is judged to be acceptable. ・C: If there are 11 or more defects of 0.16 μm or larger per wafer, it is judged to be a defective product because there is a concern that abnormalities may occur in the electrical characteristics of the wafer.

[0123] 3.2.4. Evaluation Results Tables 3 and 4 below show the composition of the stock solution composition and the semiconductor processing composition (cleaning agent), as well as the evaluation results.

[0124]

[0125]

[0126] The components used in Tables 3 and 4 above are the same as those used in Tables 1 and 2 above.

[0127] As shown in Table 3 above, semiconductor processing compositions (cleaning agents) obtained from stock solutions with an MA / MB ratio of 0.1 to 1000 exhibited good corrosion characteristics for tungsten films on pattern wafers, and also yielded good results in defect evaluation after the cleaning process using these compositions.

[0128] On the other hand, as shown in Table 4 above, when the semiconductor processing compositions (cleaning agents) of Comparative Examples 11, 12, 14, 18, and 19 did not contain component (B), the corrosion evaluation and / or defect evaluation results were poor. When the MA / MB was not within the range of 0.1 to 1000, as in Comparative Examples 15 and 16, the corrosion evaluation or defect evaluation results were poor. When the semiconductor processing composition (cleaning agent) of Comparative Example 17 did not contain component (A), the corrosion evaluation results were poor. When the pH was outside the range of 2 to 9, as in Comparative Examples 12 and 13, the corrosion evaluation results were poor.

[0129] The present invention is not limited to the embodiments described above, and various modifications are possible. For example, the present invention includes configurations that are substantially identical to the configurations described in the embodiments (for example, configurations with the same function, method and result, or configurations with the same purpose and effect). The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as the configurations described in the embodiments. Furthermore, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0130] 10...Substrate, 12...Silicon oxide film, 14...Contact hole, 16...Tungsten film, 42...Slurry supply nozzle, 44...Semiconductor processing composition, 46...Polishing pad, 48...Turntable, 50...Semiconductor substrate, 52...Carrier head, 54...Water supply nozzle, 56...Dresser, 62...300mm Si, 64...100nm PE-TEOS (SiO ２ ), 66...10nm Ti, 68...6nm TiN, 70...200nm W, 100...workpiece, 200...semiconductor processing equipment, 300...patterned wafer

Claims

1. A semiconductor processing composition comprising (A) a heterocyclic compound, (B) a cationic water-soluble polymer, and (C) a liquid medium, wherein the content of component (A) is MA [parts by mass] and the content of component (B) is MB [parts by mass], the ratio MA / MB = 0.1 to 1000 and the pH is 2 to 9.

2. The semiconductor processing composition according to claim 1, wherein component (A) is a nitrogen-containing heterocyclic compound.

3. The semiconductor processing composition according to claim 2, wherein the nitrogen-containing heterocyclic compound has an isothiazolin structure or a thiazole structure.

4. The semiconductor processing composition according to claim 1, wherein the number-average molecular weight (Mn) of component (B) is 1,000 or more and 20,000 or less.

5. The semiconductor processing composition according to claim 1, further comprising abrasive particles.

6. A processing method comprising the step of processing using a semiconductor processing composition according to any one of claims 1 to 5.

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