JP7641459B2 - Semiconductor cleaning composition and method for cleaning semiconductor substrates - Google Patents

Description

The present invention relates to a semiconductor cleaning composition and a method for cleaning semiconductor substrates using the same.

CMP (Chemical Mechanical Polishing) used in the manufacture of semiconductor devices is a technique in which the workpiece is pressed against a polishing pad, and the workpiece and the polishing pad are slid against each other while a chemical mechanical polishing composition (hereinafter also referred to as "CMP slurry") is supplied onto the polishing pad, thereby chemically and mechanically polishing the workpiece. The CMP slurry used in such CMP contains abrasive grains as well as chemicals such as an etching agent and a pH adjuster. When CMP is performed, polishing debris is generated from the workpiece, the polishing pad, and the chemical mechanical polishing composition. If this polishing debris remains on the workpiece, it may cause fatal equipment defects. For this reason, a process of cleaning the workpiece after CMP is essential.

On the surface of the workpiece after CMP, metal wiring materials such as copper and tungsten, insulating materials such as silicon oxide and silicon nitride, barrier metal materials such as tantalum nitride and titanium nitride, etc. are exposed. When such different materials coexist on the polished surface, it is necessary to remove only the contamination from the polished surface and process it without causing damage such as corrosion. For example, Patent Document 1 discloses a technology for suppressing corrosion of the polished surface on which wiring materials and barrier metal materials are exposed using an acidic semiconductor cleaning composition. In addition, for example, Patent Documents 2 and 3 disclose a technology for treating the polished surface on which wiring materials and barrier metal materials such as cobalt are exposed using a neutral to alkaline semiconductor cleaning composition.

JP 2010-258014 A JP 2009-055020 A JP 2013-157516 A

However, with the recent trend toward finer circuit structures, there is a demand for processing technologies that can further reduce damage to the wiring material of the processed object and effectively remove contamination from the surface of the processed object.

Some aspects of the present invention provide a semiconductor cleaning composition that suppresses corrosion damage to wiring substrates on which silicon oxide or silicon nitride is exposed and can efficiently remove contamination from the surface of the workpiece, and a method for cleaning semiconductor substrates using the composition.

The present invention has been made to solve at least some of the problems described above, and can be realized in any of the following forms:

One aspect of the semiconductor cleaning composition according to the present invention is
A compound (A) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 8 to 12 carbon atoms,
and a compound (B) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 13 to 18 carbon atoms,
When the content of the compound (A) is MA (mass %) and the content of the compound (B) is MB (mass %), MA/MB=1 to 30.
-SO ₃ ^- M ⁺ ...(1)
-COO ^- M ⁺ ...(2)
(In the above formulas (1) and (2), M ⁺ represents a monovalent cation.)

（上記式（３）中、Ｒ^１ないしＲ^４は、各々独立して水素原子あるいは有機基を示す。） In one embodiment of the semiconductor cleaning composition,
In the above general formula (1) or (2), M ⁺ may be a cation represented by the following general formula (3).

(In the above formula (3), ^R1 to ^R4 each independently represent a hydrogen atom or an organic group.)

In any one of the embodiments of the semiconductor cleaning composition,
It may further contain an organic acid.

In any one of the embodiments of the semiconductor cleaning composition,
The pH may be from 2 to 7.

One aspect of the method for cleaning a semiconductor substrate according to the present invention includes:
The method includes a step of treating a wiring board on which at least one of silicon oxide and silicon nitride is exposed, with the semiconductor cleaning composition according to any one of the above embodiments.

One aspect of the method for cleaning a semiconductor substrate according to the present invention includes:
The method includes a step of chemically and mechanically polishing a semiconductor substrate and then treating the semiconductor substrate with the semiconductor cleaning composition according to any one of the above aspects.

By using the semiconductor cleaning composition of the present invention, it is possible to suppress damage caused by corrosion to wiring boards on which silicon oxide or silicon nitride is exposed, and to efficiently remove contamination from the surface of the workpiece.

1A to 1C are cross-sectional views each showing a schematic process for producing a wiring substrate used in the method for cleaning a semiconductor substrate according to the embodiment of the present invention. 1A to 1C are cross-sectional views each showing a schematic process for producing a wiring substrate used in the method for cleaning a semiconductor substrate according to the embodiment of the present invention.

The following describes in detail preferred embodiments of the present invention. Note that the present invention is not limited to the following embodiments, and includes various modifications that are implemented within the scope of the present invention.

1. Semiconductor Cleaning Composition A semiconductor cleaning composition according to one embodiment of the present invention contains a compound (A) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 8 to 12 carbon atoms (also referred to simply as "compound (A)" in this specification), and a compound (B) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 13 to 18 carbon atoms (also referred to simply as "compound (B)" in this specification), in which when the content of the compound (A) is MA (mass %) and the content of the compound (B) is MB (mass %), MA/MB=1 to 30.
-SO ₃ ^- M ⁺ ...(1)
-COO ^- M ⁺ ...(2)
(In the above formulas (1) and (2), M ⁺ represents a monovalent cation.)

The semiconductor cleaning composition according to this embodiment is a composition for cleaning wiring boards on which silicon oxide or silicon nitride is exposed. The semiconductor cleaning composition according to this embodiment may be a concentrated type intended to be used after dilution with a liquid medium such as pure water or an organic solvent, or may be a non-diluted type intended to be used as is without dilution. In this specification, unless it is specified whether it is a concentrated type or a non-diluted type, the term "semiconductor cleaning composition" is interpreted as a concept including both concentrated and non-diluted types.

Such a semiconductor cleaning composition can be used as a cleaning agent for removing contaminants such as particles and organic residues present on the surface of a wiring substrate on which silicon oxide or silicon nitride is exposed mainly after CMP. Each component contained in the semiconductor cleaning composition according to this embodiment will be described in detail below.

1.1. Compound (A)
The semiconductor cleaning composition according to this embodiment contains a compound (A) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 8 to 12 carbon atoms.
-SO ₃ ^- M ⁺ ...(1)
-COO ^- M ⁺ ...(2)
(In the above formulas (1) and (2), M ⁺ represents a monovalent cation.)

Compound (A) has the function of adsorbing to the surface of the treated object and reducing damage caused by corrosion. Therefore, when the semiconductor cleaning composition according to this embodiment contains compound (A), damage caused by corrosion to the wiring board of the treated object can be suppressed. In addition, when the treated object is treated with the semiconductor cleaning composition according to this embodiment and then rinsed with ultrapure water or pure water, compound (A) is washed away without remaining on the wiring board, so that a clean, contaminant-free treated surface can be obtained. Furthermore, compound (A) also functions as a pH adjuster for adjusting the pH of the semiconductor cleaning composition.

The content of compound (A) in the semiconductor cleaning composition according to this embodiment can be appropriately changed depending on the material, such as the metal wiring material, such as copper or tungsten, the insulating material, such as silicon oxide or silicon nitride, or the barrier metal material, such as tantalum nitride or titanium nitride, that is exposed on the surface of the workpiece after CMP, and the composition of the CMP slurry used.

Furthermore, the content of compound (A) can be appropriately changed depending on the dilution degree of the concentrated type semiconductor cleaning composition according to this embodiment. The content of compound (A) is preferably 0.01 to 1 mass%, more preferably 0.02 to 0.5 mass%, and particularly preferably 0.025 to 0.3 mass%, when the total mass of the non-diluted type semiconductor cleaning composition is taken as 100 mass%. When the content of compound (A) is within the above range, it is possible to reduce corrosion by adsorbing to the surface of the wiring board of the treated object and protecting it, and to suppress damage to the wiring board. In addition, after the treated object is rinsed with ultrapure water or pure water, compound (A) is washed away without remaining on the surface of the wiring board, so that a cleaner and uncontaminated treated surface can be obtained.

In the above general formulas (1) and (2), examples of the monovalent cation represented by M ⁺ include, but are not limited to, H ⁺ , Li ⁺ , Na ⁺ , K ⁺ , and cations represented by the following general formula (3). Among these, the monovalent cation represented by M ⁺ is preferably the cation represented by the following general formula (3) because it can reduce metal contamination of the treated surface.

（上記式（３）中、Ｒ^１ないしＲ^４は、各々独立して水素原子あるいは有機基を示す。）

(In the above formula (3), ^R1 to ^R4 each independently represent a hydrogen atom or an organic group.)

In the above general formula (3), examples of the organic group represented by R ¹ to R ⁴ include an alkyl group, a cycloalkyl group, an alkenyl group, a hydroxyalkyl group, an aralkyl group, and an aryl group.

As the alkyl group, a lower alkyl group having 1 to 6 carbon atoms is generally preferred, and a lower alkyl group having 1 to 4 carbon atoms is more preferred. The alkyl group may be linear or branched. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, and a tert-hexyl group.

As the cycloalkyl group, those having 3 to 6 carbon atoms are usually preferred. Specific examples of cycloalkyl groups include a cyclopentyl group and a cyclohexyl group.

The alkenyl group is preferably one having 2 to 6 carbon atoms. The alkenyl group may be linear or branched. Specific examples of the alkenyl group include vinyl, n-propenyl, iso-propenyl, n-butenyl, iso-butenyl, sec-butenyl, and tert-butenyl.

As the hydroxyalkyl group, those having 1 to 6 carbon atoms are usually preferred, and those having 1 to 4 carbon atoms are more preferred. The hydroxyalkyl group may be linear or branched. The substitution position of the hydroxy group contained in the hydroxyalkyl group is not particularly limited. Specific examples of the hydroxyalkyl group include a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, a dihydroxybutyl group, a hydroxypentyl group, a dihydroxypentyl group, a hydroxyhexyl group, and a dihydroxyhexyl group.

As the aralkyl group, those having 7 to 12 carbon atoms are usually preferred. Specific examples of aralkyl groups include a benzyl group, a phenethyl group, a phenylpropyl group, a phenylbutyl group, a phenylhexyl group, a methylbenzyl group, a methylphenethyl group, and an ethylbenzyl group.

As the aryl group, those having 6 to 14 carbon atoms are generally preferred. Specific examples of the aryl group include a phenyl group, an o-tolyl group, an m-tolyl group, an p-tolyl group, a 2,3-xylyl group, a 2,4-xylyl group, a 2,5-xylyl group, a 2,6-xylyl group, a 3,5-xylyl group, a naphthyl group, and an anthryl group.

The aromatic ring of the aralkyl group or aryl group may have a substituent such as a lower alkyl group, such as a methyl group or an ethyl group, a halogen atom, a nitro group, an amino group, or a hydroxyl group.

Specific examples of compound (A) include alkyl (C8-C12) triethanolamine sulfate, alkyl (C8-C12) diethanolamine sulfate, alkyl (C8-C12) monoethanolamine sulfate, alkyl (C8-C12) triethanolamine benzenesulfonate, polyoxyethylene alkyl (C8-C12) ether triethanolamine acetate, polyoxyethylene alkyl (C8-C12) ether triethanolamine sulfate, etc. These compounds (A) may be used alone or in combination of two or more. Here, "alkyl (C8-C12)" refers to a straight-chain or branched-chain alkyl group having 8 to 12 carbon atoms.

1.2. Compound (B)
The semiconductor cleaning composition according to this embodiment contains a compound (B) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 13 to 18 carbon atoms.
-SO ₃ ^- M ⁺ ...(1)
-COO ^- M ⁺ ...(2)
(In the above formulas (1) and (2), M ⁺ represents a monovalent cation.)

Compound (B) acts on the surface of the workpiece to effectively remove contaminants such as organic residues. That is, when the workpiece is treated with the semiconductor cleaning composition according to this embodiment and then rinsed with ultrapure water or pure water, contaminants such as organic residues that interact with compound (B) are washed away together with compound (B), so that a clean, contaminant-free treated surface can be obtained. Furthermore, compound (B) also functions as a pH adjuster for adjusting the pH of the semiconductor cleaning composition.

The content of compound (B) in the semiconductor cleaning composition according to this embodiment can be appropriately changed depending on the material, such as the metal wiring material, such as copper or tungsten, the insulating material, such as silicon oxide or silicon nitride, or the barrier metal material, such as tantalum nitride or titanium nitride, exposed on the surface of the workpiece, and the composition of the CMP slurry used.

Furthermore, the content of compound (B) can be appropriately changed depending on the degree of dilution of the concentrated type semiconductor cleaning composition according to this embodiment. The content of compound (B) is preferably 0.001 to 0.5 mass%, more preferably 0.01 to 0.1 mass%, and particularly preferably 0.02 to 0.05 mass%, when the total mass of the non-diluted type semiconductor cleaning composition is taken as 100 mass%. When the content of compound (B) is within the above range, it interacts with contaminants such as organic residues remaining on the surface of the treated object to increase water solubility, and after rinsing the treated object with ultrapure water or pure water, a cleaner, contaminant-free treated surface can be obtained.

In the above general formulas (1) and (2), examples of the monovalent cation represented by M ⁺ include, but are not limited to, H ⁺ , Li ⁺ , Na ⁺ , K ⁺ , and cations represented by the following general formula (3). Among these, the monovalent cation represented by M ⁺ is preferably the cation represented by the following general formula (3) because it can reduce metal contamination of the treated surface.

（上記式（３）中、Ｒ^１ないしＲ^４は、各々独立して水素原子あるいは有機基を示す。）

(In the above formula (3), ^R1 to ^R4 each independently represent a hydrogen atom or an organic group.)

In the above general formula (3), examples of the organic groups represented by R ¹ to R ⁴ include the same groups as those in compound (A).

Specific examples of compound (B) include alkyl (C13-C18) triethanolamine sulfate, alkyl (C13-C18) diethanolamine sulfate, alkyl (C13-C18) monoethanolamine sulfate, alkyl (C13-C18) ammonium sulfate, alkyl (C13-C18) triethanolamine benzenesulfonate, polyoxyethylene alkyl (C13-C18) ether triethanolamine acetate, polyoxyethylene alkyl (C13-C18) ether triethanolamine sulfate, etc. These compounds (B) may be used alone or in combination of two or more. Here, "alkyl (C13-C18)" refers to a linear or branched alkyl group having 13 to 18 carbon atoms.

1.3 Mass ratio of compound (A) to compound (B) When the content of compound (A) in the semiconductor cleaning composition according to this embodiment is MA (mass%) and the content of compound (B) is MB (mass%), the value of MA/MB is 1 to 30, preferably 1 to 25, and more preferably 1 to 20. When the value of MA/MB, which indicates the mass balance between compound (A) and compound (B), is within the above range, damage caused by corrosion to wiring of a wiring board on which silicon nitride or silicon oxide is exposed can be suppressed, and contamination can be efficiently removed from the surface of the object to be treated.

1.4 Other Components The semiconductor cleaning composition according to this embodiment may contain, in addition to the above-mentioned components and the liquid medium which is the main component, organic acids, amines, water-soluble polymers, and other components as necessary.

1.4.1. Liquid medium The semiconductor cleaning composition according to this embodiment is a liquid containing a liquid medium as a main component. As the liquid medium, an aqueous medium containing water as a main component is preferable. Examples of such aqueous media include water, a mixed medium of water and alcohol, and a mixed medium containing water and an organic solvent compatible with water. Among these, it is preferable to use water, a mixed medium of water and alcohol, and it is more preferable to use water.

1.4.2. Organic acid The semiconductor cleaning composition according to this embodiment may contain an organic acid. The organic acid preferably has one or more acidic groups such as a carboxy group or a sulfo group. Note that the "organic acid" in the present invention is a concept that does not include the above-mentioned compound (A) or compound (B), and is a different component.

Specific examples of organic acids include citric acid, maleic acid, malic acid, tartaric acid, oxalic acid, malonic acid, succinic acid, ethylenediaminetetraacetic acid, acrylic acid, methacrylic acid, benzoic acid, phenyllactic acid, phenylsuccinic acid, naphthalenesulfonic acid, and salts thereof. These organic acids may be used alone or in combination of two or more.

As the organic acid, an amino acid may be used. Examples of the amino acid include a compound represented by the following general formula (4).

（上記一般式（４）中、Ｒ^５、Ｒ^６およびＲ^７はそれぞれ独立に、水素原子、炭素数１～１０の炭化水素基、およびヘテロ原子を有する炭素数１～２０の有機基よりなる群から選択されるいずれかを表す。）

(In the above general formula (4), R ⁵ , R ⁶ and R ⁷ each independently represent any one selected from the group consisting of a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and an organic group having 1 to 20 carbon atoms and a hetero atom.)

Examples of the hydrocarbon group having 1 to 10 carbon atoms for R ⁵ , R ⁶ and R ⁷ in the above general formula (4) include saturated aliphatic hydrocarbon groups having 1 to 10 carbon atoms, cyclic saturated hydrocarbon groups having 1 to 10 carbon atoms, and aromatic hydrocarbon groups having 6 to 10 carbon atoms. Among these, saturated aliphatic hydrocarbon groups having 1 to 10 carbon atoms are preferred.

Examples of the organic group having 1 to 20 carbon atoms and containing a hetero atom for R ⁵ , R ⁶ and R ⁷ in the above general formula (4) include a hydrocarbon group having 1 to 20 carbon atoms and containing a carboxy group, a hydrocarbon group having 1 to 20 carbon atoms and containing a hydroxy group, a hydrocarbon group having 1 to 20 carbon atoms and containing an amino group, a hydrocarbon group having 1 to 20 carbon atoms and containing a mercapto group, an organic group having 1 to 20 carbon atoms and containing a heterocycle, and the like. These groups may further contain hetero atoms such as oxygen, sulfur or halogen, and a part of them may be substituted with other substituents.

Examples of compounds represented by the above general formula (4) include alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, serine, threonine, tyrosine, valine, tryptophan, histidine, 2-amino-3-aminopropanoic acid, dodecylaminoethylaminoethylglycine, etc. These amino acids may be used alone or in combination of two or more.

As the organic acid, it is also preferable to use a compound represented by the following general formula (5):

（上記一般式（５）中、Ｒ^８は、炭素数１～２０の有機基を示す。）

(In the above general formula (5), ^R8 represents an organic group having 1 to 20 carbon atoms.)

Examples of the organic group having 1 to 20 carbon atoms in R ⁸ in the above general formula (5) include saturated aliphatic hydrocarbon groups having 6 to 20 carbon atoms, unsaturated aliphatic hydrocarbon groups having 6 to 20 carbon atoms, organic groups having 6 to 20 carbon atoms with a cyclic saturated hydrocarbon group, organic groups having 6 to 20 carbon atoms with an unsaturated cyclic hydrocarbon group, hydrocarbon groups having 1 to 20 carbon atoms with a carboxy group, hydrocarbon groups having 1 to 20 carbon atoms with a hydroxy group, hydrocarbon groups having 1 to 20 carbon atoms with an amino group, and organic groups having 1 to 20 carbon atoms with a heterocyclic group. Among these, organic groups having 6 to 20 carbon atoms with an unsaturated cyclic hydrocarbon group and hydrocarbon groups having 1 to 20 carbon atoms with a carboxy group are preferred, and organic groups having 6 to 20 carbon atoms with an aryl group and carboxymethyl groups are particularly preferred. However, the concept of the compound represented by the above general formula (5) does not include the compound represented by the above general formula (4).

Specific examples of the compound represented by the above general formula (5) include hydroxyphenyllactic acid, hydroxymalonic acid, etc., and among these, hydroxyphenyllactic acid is preferable. The above-exemplified compounds may be used alone or in combination of two or more.

The content of organic acid can be changed as appropriate depending on the materials, such as metal wiring materials such as copper and tungsten, insulating materials such as silicon oxide and silicon nitride, and barrier metal materials such as tantalum nitride and titanium nitride, that are exposed on the surface of the workpiece after CMP, and the composition of the CMP slurry used.

Furthermore, the content of the organic acid can be appropriately changed depending on the degree of dilution of the concentrated type semiconductor cleaning composition according to this embodiment. The content of the organic acid is preferably 0.0001% by mass or more, more preferably 0.0005% by mass or more, and preferably 1% by mass or less, more preferably 0.5% by mass or less, when the total mass of the cleaning agent prepared by diluting the concentrated type semiconductor cleaning composition or the non-diluted type semiconductor cleaning composition is taken as 100% by mass. When the content of the organic acid is within the above range, impurities attached to the wiring board surface may be effectively removed. In addition, excessive etching may be more effectively suppressed, and a good treated surface may be obtained.

1.4.3. Amines The semiconductor cleaning composition according to this embodiment may contain amines (excluding amino acids). It is believed that the amines function as etching agents. It is believed that by containing amines, metal oxide films (e.g., CuO, Cu ₂ O, and Cu(OH) ₂ layers) and organic residues on the wiring substrate can be etched and removed in the treatment process after CMP.

The amine is preferably a water-soluble amine. "Water-soluble" means that the mass 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.

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, tripropanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, and the like. Examples of primary amines include methylamine, ethylamine, propylamine, butylamine, pentylamine, 1,3-propanediamine, and the like. Examples of secondary amines include piperidine and piperazine, and the like. Examples of tertiary amines include trimethylamine and triethylamine, and the like. These amines may be used alone or in combination of two or more.

Among these amines, monoethanolamine and monoisopropanolamine are preferred, and monoethanolamine is more preferred, because they are highly effective in etching metal oxide films and organic residues on wiring substrates.

The amount of amine contained can be changed as appropriate depending on the material, such as the metal wiring material (such as copper or tungsten) exposed on the surface of the workpiece after CMP, the insulating material (such as silicon oxide or silicon nitride), or the barrier metal material (such as tantalum nitride or titanium nitride), and the composition of the CMP slurry used.

Furthermore, the amine content can be appropriately changed depending on the degree of dilution of the concentrated semiconductor cleaning composition according to this embodiment. The amine content is preferably 0.0001 mass% or more, more preferably 0.0005 mass% or more, and preferably 1 mass% or less, more preferably 0.5 mass% or less, when the total mass of the cleaning agent prepared by diluting the concentrated semiconductor cleaning composition or the non-diluted semiconductor cleaning composition is taken as 100 mass%. If the amine content is within the above range, the metal oxide film and organic residues on the wiring board may be more effectively etched and removed in the cleaning process after CMP.

1.4.4. Water-soluble polymer The semiconductor cleaning composition according to this embodiment may contain a water-soluble polymer. The water-soluble polymer has a function of adsorbing to the surface of the object to be treated and reducing corrosion. Therefore, when the semiconductor cleaning composition according to this embodiment contains a water-soluble polymer, corrosion of the object to be treated may be reduced. "Water-soluble" has the same meaning as the above definition. In addition, "water-soluble polymer" refers to a water-soluble compound in which two or more repeating units are linked together in a linear or mesh-like manner via covalent bonds.

Examples of such 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 containing repeating units having aromatic hydrocarbon groups obtained by condensing benzenesulfonic acid, naphthalenesulfonic acid, and the like with formalin, and salts thereof; vinyl-based synthetic polymers such as polyvinyl alcohol, polyethylene oxide, polyethylene glycol, polyvinylpyrrolidone, polyvinylpyridine, polyacrylamide, polyvinylformamide, polyethyleneimine, polyvinyloxazoline, polyvinylimidazole, and polyallylamine; and modified products of natural polysaccharides such as hydroxyethyl cellulose, carboxymethyl cellulose, and processed starch. These water-soluble polymers can be used alone or in combination of two or more.

The water-soluble polymer used in this embodiment may be a homopolymer, or may be a copolymer obtained by copolymerizing two or more types of monomers. Examples of such monomers that can be used include monomers having a carboxy group, monomers having a sulfonic acid group, monomers having a hydroxy group, monomers having a polyethylene oxide chain, monomers having an amino group, and monomers having a heterocycle.

The weight average molecular weight (Mw) of the water-soluble polymer used in this embodiment is preferably 1,000 or more and 1,500,000 or less, more preferably 3,000 or more and 1,200,000 or less. Note that "weight average molecular weight" refers to the weight average molecular weight in terms of polyethylene glycol measured by GPC (gel permeation chromatography).

The viscosity of the semiconductor cleaning composition according to this embodiment at 25°C is preferably less than 5 mPa·s, more preferably 4 mPa·s or less, even more preferably 2 mPa·s or less, even more preferably 1.2 mPa·s or less, and particularly preferably 1 mPa·s or less. When the viscosity of the semiconductor cleaning composition at 25°C is within the above range, a sufficient filtration speed can be obtained when filtering and purifying the semiconductor cleaning composition, and a sufficient throughput can be obtained for practical use. In addition, when the viscosity of the semiconductor cleaning composition at room temperature is within the above range, even if the surface of the treated object is uneven in the treatment process using the semiconductor cleaning composition, the composition can penetrate the unevenness and come into contact with the uneven surface to treat it, so that the surface of the treated object can be treated more uniformly. When the viscosity of the semiconductor cleaning composition at 25°C exceeds the above range, the viscosity becomes too high, and the semiconductor cleaning composition may not be stably supplied to the treated object. The viscosity of the semiconductor cleaning composition is determined almost by the weight average molecular weight and content of the water-soluble polymer to be added, so it is advisable to adjust it while taking into consideration the balance between them.

The viscosity of the semiconductor cleaning composition refers to the Ubbelohde viscosity measured in accordance with JIS K2283.

The content of the water-soluble polymer can be appropriately changed depending on the materials, such as the metal wiring material (e.g., copper or tungsten) exposed on the surface of the workpiece after CMP, the insulating material (e.g., silicon oxide or silicon nitride), and the barrier metal material (e.g., tantalum nitride or titanium nitride), and the composition of the semiconductor cleaning composition used.

The content of the water-soluble polymer can also be appropriately changed depending on the degree of dilution of the concentrated semiconductor cleaning composition according to this embodiment. The content of the water-soluble polymer is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and preferably 1% by mass or less, more preferably 0.1% by mass or less, when the total mass of the cleaning agent prepared by diluting the concentrated semiconductor cleaning composition or the non-diluted semiconductor cleaning composition is taken as 100% by mass. When the content of the water-soluble polymer is within the above range, it is possible to achieve both the inhibition of corrosion and the effect of removing particles and metal impurities contained in the semiconductor cleaning composition from the wiring board, and a better treated surface is easily obtained.

1.4.5. Other Components The semiconductor cleaning composition according to this embodiment may contain other necessary components, such as a pH adjuster and a surfactant other than the above-mentioned compound (A) and compound (B) (hereinafter, also referred to as "other surfactants").

<pH Adjuster>
The pH of the semiconductor cleaning composition according to this embodiment is preferably 7 or less, more preferably 6 or less, and preferably 2 or more, more preferably 3 or more. When the pH of the semiconductor cleaning composition is within the above range, it is possible to promote both the inhibition of corrosion of wiring materials containing copper or tungsten and the effect of removing organic residues, and it is easy to obtain a better treated surface.

In the semiconductor cleaning composition according to this embodiment, if the desired pH is not obtained even when the above-mentioned components are contained, a pH adjuster may be added separately to adjust the pH to within the above range. Examples of pH adjusters include inorganic acids such as phosphoric acid, nitric acid, and sulfuric acid; alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide; and basic compounds such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, and ammonia. These pH adjusters may be used alone or in combination of two or more.

<Other surfactants>
The semiconductor cleaning composition according to this embodiment may contain a surfactant other than the above-mentioned compound (A) and compound (B). As the other surfactant, a known surfactant can be appropriately used, but a nonionic surfactant can be preferably used. By containing the other surfactant, the effect of removing particles and metal impurities contained in the CMP slurry from the wiring board is enhanced, and a better treated surface may be obtained.

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 alone or in combination of two or more.

The content of other surfactants can be changed as appropriate depending on the materials, such as metal wiring materials such as copper and tungsten, insulating materials such as silicon oxide and silicon nitride, and barrier metal materials such as tantalum nitride and titanium nitride, that are exposed on the surface of the workpiece after CMP, and the composition of the CMP slurry used.

Furthermore, the content of the other surfactants can be appropriately changed depending on the degree of dilution of the concentrated semiconductor cleaning composition according to this embodiment. The content of the other surfactants is preferably 0.001% by mass or more and 1% by mass or less when the total mass of the cleaning agent prepared by diluting the concentrated semiconductor cleaning composition or the non-diluted semiconductor cleaning composition is taken as 100% by mass. If the content of the other surfactants is within the above range, it may be possible to efficiently remove particles and metal impurities contained in the CMP slurry from the surface of the workpiece in the treatment step after the completion of CMP.

1.5. Method for preparing semiconductor cleaning composition The semiconductor cleaning composition according to this embodiment is not particularly limited and can be prepared by using a known method. 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 filtering the mixture. The order and method of mixing the above-mentioned components are not particularly limited.

In the method for preparing the semiconductor cleaning composition according to the present embodiment, it is preferable to control the amount of particles by filtering with a depth type or pleat type filter as necessary. Here, the depth type filter is a high-precision filtration filter also called a deep layer filtration or volume filtration type filter. Such depth type filters include those having a laminated structure in which filtration membranes having a large number of holes are laminated, and those having rolled up fiber bundles. Specific examples of depth type filters include Profile II, Nexis NXA, Nexis NXT, Polyfine XLD, Ulti Pleats Profile, etc. (all manufactured by Nippon Pall Corporation), depth cartridge filters, wound cartridge filters, etc. (all manufactured by Advantech Co., Ltd.), CP filters, BM filters, etc. (all manufactured by Chisso Corporation), Slope Pure, Dia, Microsilia, etc. (all manufactured by Roki Techno Co., Ltd.), etc.

Examples of pleated type filters include cylindrical high-precision filtration filters obtained by pleating a precision filtration membrane sheet made of nonwoven fabric, filter paper, metal mesh, etc., 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.Specific examples include HDCII, Polyfine II, etc. (all manufactured by Nippon Pall Corporation), PP pleated cartridge filter (manufactured by Advantec Co., Ltd.), Porousfine (manufactured by Chisso Corporation), Sartonpore, Micropure, etc. (all manufactured by Roki Techno Co., Ltd.), etc.

It is preferable to use a filter with a rated filtration accuracy of 0.01 to 20 μm. By using a filter with a rated filtration accuracy in this range, it is possible to efficiently obtain a filtrate in which the number of particles with a particle diameter of 20 μm or more per mL is zero when measured with a particle counter. In addition, the number of coarse particles captured by the filter is minimized, which extends the usable period of the filter.

2. Cleaning agent In the present invention, the "cleaning agent" refers to a liquid agent prepared by diluting the above-mentioned semiconductor cleaning composition with a liquid medium, or the above-mentioned semiconductor cleaning composition itself, which is actually used to clean the surface to be treated. When preparing a cleaning agent by diluting the above-mentioned semiconductor cleaning composition with a liquid medium, the above-mentioned semiconductor cleaning composition is a concentrated type semiconductor cleaning composition, and each component is usually present in a concentrated state. Therefore, each user prepares a cleaning agent by appropriately diluting the above-mentioned concentrated type semiconductor cleaning composition with a liquid medium. On the other hand, when the above-mentioned semiconductor cleaning composition itself is a cleaning agent, the above-mentioned cleaning composition is a non-diluted type semiconductor cleaning composition, and is used as it is as a cleaning agent.

The liquid medium used for dilution here is the same as the liquid medium contained in the semiconductor cleaning composition described above, and can be appropriately selected from the liquid media exemplified above.

A method for diluting a concentrated semiconductor cleaning composition by adding a liquid medium includes merging a pipe supplying the concentrated semiconductor cleaning composition and a pipe supplying the liquid medium midway, mixing them, and supplying the mixed cleaning agent to the surface to be treated. This mixing can be performed by any of the commonly used methods, such as a method in which the liquids are mixed by collision through a narrow passage under pressure; a method in which the pipe is filled with a filler such as a glass tube, and the liquid flow is repeatedly divided, separated, and merged; or a method in which a blade that rotates by power is provided in the pipe.

Another method for diluting a concentrated semiconductor cleaning composition by adding a liquid medium is to provide separate pipes for supplying the concentrated semiconductor cleaning composition and liquid medium, supply a predetermined amount of liquid from each pipe to the surface to be treated, and mix them on the surface to be treated. Another method for diluting a concentrated semiconductor cleaning composition by adding a liquid medium is to put a predetermined amount of concentrated semiconductor cleaning composition and a predetermined amount of liquid medium in one container, mix them, and then supply the mixed cleaning agent to the surface to be treated.

When diluting a concentrated type semiconductor cleaning composition by adding a liquid medium, the dilution ratio is preferably 1 to 500 parts by mass (1 to 500 times) by adding a liquid medium to 1 part by mass of the concentrated type semiconductor cleaning composition, more preferably 20 to 500 parts by mass (20 to 500 times), and particularly preferably 30 to 300 parts by mass (30 to 300 times). It is preferable to dilute with the same liquid medium as the liquid medium contained in the concentrated type semiconductor cleaning composition described above. By making the semiconductor cleaning composition in a concentrated state in this way, it becomes possible to transport and store the cleaning agent in a smaller container than when the cleaning agent is transported and stored as it is. As a result, the costs of transportation and storage can be reduced. In addition, since a smaller amount of cleaning agent is purified than when the cleaning agent is purified by filtering or the like, the purification time can be shortened, which makes mass production possible.

3. Method for cleaning semiconductor substrate The method for cleaning semiconductor substrate according to one embodiment of the present invention includes a step of treating a wiring substrate on which at least one of silicon oxide and silicon nitride is exposed, with the above-mentioned semiconductor cleaning composition. Hereinafter, an example of the method for cleaning semiconductor substrate according to this embodiment will be described in detail with reference to the drawings.

<Preparation of wiring board>
1A to 1C are cross-sectional views that are schematic diagrams showing a process for producing a wiring board used in the method for cleaning a semiconductor substrate according to the present embodiment. Such a wiring board is formed through the following process.

Figure 1 is a cross-sectional view showing a typical example of a workpiece before CMP processing. As shown in Figure 1, the workpiece 100 has a base 10. The base 10 may be composed of, for example, a silicon substrate and a silicon oxide film formed thereon. Furthermore, although not shown, functional devices such as transistors may be formed on the base 10.

The workpiece 100 is constructed by sequentially laminating on a substrate 10 an insulating film 12 having a wiring recess 20 formed therein, a barrier metal film 14 provided to cover the surface of the insulating film 12 and the bottom and inner wall surface of the wiring recess 20, and a wiring metal film 16 formed on the barrier metal film 14 and filling the wiring recess 20.

Examples of the insulating film 12 include silicon oxide films formed by vacuum processes (e.g., PETEOS film (Plasma Enhanced-TEOS film), HDP film (High Density Plasma Enhanced-TEOS film), silicon oxide films obtained by thermal chemical vapor deposition, etc.), insulating films called FSG (Fluorine-doped silicate glass), boron phosphosilicate film (BPSG film), insulating films called SiON (Silicon oxynitride), silicon nitride, etc.

Examples of the barrier metal film 14 include tantalum, titanium, cobalt, ruthenium, manganese, and compounds of these. The barrier metal film 14 is often formed from one of these elements, but it can also be formed from a combination of two or more elements, such as titanium and titanium nitride.

Examples of the wiring metal film 16 include copper, aluminum, tungsten, and alloys of these metals. The wiring metal film 16 is often formed from one of these materials.

As shown in FIG. 1, the wiring metal film 16 needs to completely fill the wiring recess 20. To achieve this, a wiring metal film of 100 to 10,000 Å is typically deposited by chemical vapor deposition, physical vapor deposition, or atomic layer deposition.

Next, the wiring metal film 16 of the workpiece 100 in FIG. 1 other than the portion buried in the wiring recess 20 is polished at high speed by CMP until the barrier metal film 14 is exposed (first polishing step). Furthermore, the barrier metal film 14 exposed on the surface is polished by CMP (second polishing step). In this way, the wiring substrate 200 as shown in FIG. 2 is obtained.

<Processing of wiring board>
2 is treated with the cleaning agent described above. According to the semiconductor substrate cleaning method of this embodiment, when treating a wiring substrate in which silicon oxide or silicon nitride is exposed after CMP, damage to the wiring substrate caused by corrosion can be suppressed and contamination can be efficiently removed from the surface of the substrate.

The cleaning method is not particularly limited, but is performed by directly contacting the wiring board 200 with the above-mentioned cleaning agent. Examples of methods for directly contacting the cleaning agent with the wiring board 200 include a dip type in which a cleaning tank is filled with the cleaning agent and the wiring board is immersed in the cleaning agent; a spin type in which the wiring board is rotated at high speed while the cleaning agent is flowed down from a nozzle onto the wiring board; and a spray type in which the cleaning agent is sprayed onto the wiring board to clean it. In addition, examples of devices for performing such methods include a batch type processing device that simultaneously processes multiple wiring boards stored in a cassette, and a single-wafer processing device that processes a single wiring board by mounting it on a holder.

In the semiconductor substrate cleaning method according to this embodiment, the temperature of the cleaning agent is usually room temperature, but it may be heated to a temperature within a range that does not impair performance, for example, about 40 to 70°C.

In addition to the method of directly contacting the above-mentioned cleaning agent with the wiring board 200, it is also preferable to use a cleaning method that uses physical force in combination. This improves the removability of contamination caused by particles attached to the wiring board 200 and shortens the processing time. Examples of cleaning methods that use physical force include scrubbing using a cleaning brush and ultrasonic cleaning.

Furthermore, it is preferable to perform cleaning with ultrapure water or pure water before and/or after cleaning with the semiconductor substrate cleaning method according to this embodiment.

4. Examples The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In the examples, "parts" and "%" are based on mass unless otherwise specified.

4.1. Examples 1 to 22 and Comparative Examples 1 to 7
4.1.1. Preparation of semiconductor cleaning composition Each component was added to a polyethylene container so as to have the content ratio shown in Tables 1 to 3 below, and an appropriate amount of ion-exchanged water was added and stirred for 15 minutes. Ion-exchanged water and ammonia water (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "ammonia water") were added to this mixture as necessary so that the total amount of all components was 100 parts by mass, and compositions were prepared so as to have the pH and content shown in Tables 1 to 3 below. The mixture was then filtered through a filter with a pore size of 5 μm to obtain each semiconductor cleaning composition shown in Tables 1 to 3 below. The pH was measured using a pH meter "F52" manufactured by Horiba, Ltd.

4.1.2. Preparation of chemical mechanical polishing composition 5 kg of high-purity colloidal silica (Fuso Chemical Co., Ltd., product number: PL-3; silica concentration 20%) and 6 g of 3-mercaptopropyltrimethoxysilane (Alfa Aesar, product name: (3-mercaptopropyl)trimethoxysilane) were mixed and heated under reflux for 2 hours to obtain a thiolated silica sol. Hydrogen peroxide was added to the silica sol and heated under reflux for 8 hours to oxidize the surface of the silica particles and fix the sulfonic acid groups. In this way, a silica particle dispersion with a silica concentration of 20%, a primary particle diameter of 45 nm, and a secondary particle diameter of 68 nm was obtained. Next, 14,043 g of pure water, 3,940 g of 20% silica particle aqueous dispersion, 43 g of phosphoric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Phosphoric Acid"), and 2 g of polyvinylpyrrolidone (manufactured by Nippon Shokubai Co., Ltd., product name "Polyvinylpyrrolidone") were added to a 20 L polyethylene bottle and stirred at room temperature for 1 hour to prepare chemical mechanical polishing composition A.

4.1.3. Evaluation test Using the chemical mechanical polishing composition A prepared in "4.1.2. Preparation of chemical mechanical polishing composition", a 12-inch wafer with a 250 nm silicon nitride film and a 12-inch wafer with a 1000 nm silicon oxide film (p-TEOS film) were polished under the conditions below, and then cleaned under the conditions below using the cleaning agent prepared in "4.1.1. Preparation of semiconductor cleaning composition". Finally, brush scrubbing was performed under the conditions below to obtain cleaned objects.

After cleaning, the surface of the workpiece was inspected using a defect inspection device (KLA Tencor, model "Surfscan SP2") to count the number of defects over the entire surface. If the number of defects in the silicon oxide film and the number of defects in the silicon nitride film were both less than 100, the product was judged to be good, and if at least either the number of defects in the silicon oxide film or the number of defects in the silicon nitride film was 100 or more, the product was judged to be unsuitable for practical use and therefore defective. The results are shown in Tables 1 to 3 below.

<Polishing treatment conditions>
Polishing equipment: Applied Materials, model "Reflexion-LK"
Polishing pad: Fujibo Co., Ltd., "Porous polyurethane pad; H800-type1 (3-1S) 775"
Chemical mechanical polishing composition: Chemical mechanical polishing composition A prepared above
Chemical mechanical polishing composition supply rate: 300 mL/min Platen rotation speed: 90 rpm
Head rotation speed: 91 rpm
Head pressing pressure: 2.0 psi
Processing time: 60 seconds

<Cleaning treatment>
Polishing equipment: Applied Materials, model "Reflexion-LK"
Polishing pad: Fujibo Co., Ltd., "Porous polyurethane pad; H800-type1 (3-1S) 775"
Cleaning agent: the semiconductor cleaning composition prepared above. Cleaning agent supply rate: 300 mL/min. Platen rotation speed: 50 rpm.
Head rotation speed: 51 rpm
Head pressing pressure: 0.5 psi
Processing time: 30 seconds

<Brush scrub cleaning conditions>
Treatment agent: Pure water Upper brush rotation speed: 400 rpm
Lower brush rotation speed: 400 rpm
Substrate rotation speed: 50 rpm
Treatment agent supply rate: 1200 mL/min Treatment time: 40 seconds

4.1.4. Evaluation Results Tables 1 to 3 below show the compositions of the semiconductor cleaning compositions used in each of the Examples and Comparative Examples, as well as the evaluation results.

In Tables 1 to 3, the compounds used were as follows:
<Compound A>
Triethanolamine octyl sulfate: A 5% aqueous solution of sodium octyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Sodium n-octyl sulfate") was used to remove sodium with a strong cationic ion exchange resin (Merck type I), and then the pH was adjusted to 7 with triethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd., product name "Triethanolamine") and diluted with pure water to prepare a 1% aqueous solution of triethanolamine octyl sulfate, which was then used.
Triethanolamine decyl sulfate: A 1% aqueous solution of triethanolamine decyl sulfate was prepared in the same manner as for triethanolamine octyl sulfate, except that a 5% aqueous solution of sodium decyl sulfate (manufactured by Tokyo Chemical Industry Co., Ltd., product name "Sodium Decyl Sulfate") was used.
Triethanolamine dodecyl sulfate: Kao Corporation, product name "EMAL TD, 40% aqueous solution"
Triethanolamine dodecylbenzenesulfonate: Toho Chemical Industry Co., Ltd., product name "Lunox S-40TD, 38% aqueous solution"
Polyoxyethylene dodecyl ether triethanolamine sulfate: manufactured by Toho Chemical Industry Co., Ltd., product name "Alscope N-335T, 35.5% aqueous solution"
Triethanolamine polyoxyethylene dodecyl ether acetate: A 1% aqueous solution of triethanolamine polyoxyethylene dodecyl ether acetate was prepared in the same manner as in the case of triethanolamine octyl sulfate above, except that a 5% aqueous solution of sodium polyoxyethylene dodecyl ether acetate (manufactured by Sanyo Chemical Industries, Ltd., trade name "Viewlite LCA") was used.
Monoethanolamine decyl sulfate: A 5% aqueous solution of sodium decyl sulfate (manufactured by Tokyo Chemical Industry Co., Ltd., product name "Sodium Decyl Sulfate") was used to remove sodium with a strong cationic ion exchange resin (Merck type I), and then the pH was adjusted to 7 with aminoethanol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "2-aminoethanol") and diluted with pure water to prepare a 1% aqueous solution of monoethanolamine decyl sulfate, which was then used.
<Compound B>
Triethanolamine tridecyl sulfate: A 1% aqueous solution of triethanolamine tridecyl sulfate was prepared in the same manner as for triethanolamine octyl sulfate, except that a 5% aqueous solution of sodium tridecyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "1-sodium tridecyl sulfate") was used.
Triethanolamine tetradecyl sulfate: A 1% aqueous solution of triethanolamine tetradecyl sulfate was prepared in the same manner as for triethanolamine octyl sulfate above, except that a 5% aqueous solution of sodium tetradecyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Sodium Tetradecyl Sulfate") was used.
Triethanolamine hexadecyl sulfate: A 1% aqueous solution of triethanolamine hexadecyl sulfate was prepared in the same manner as for triethanolamine octyl sulfate above, except that a 5% aqueous solution of sodium hexadecyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Sodium hexadecyl sulfate") was used.
Triethanolamine octadecyl sulfate: A 1% aqueous solution of triethanolamine octadecyl sulfate was prepared in the same manner as for triethanolamine octyl sulfate above, except that a 5% aqueous solution of sodium octadecyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "Sodium Octadecyl Sulfate") was used.
Triethanolamine polyoxyethylene tridecyl ether acetate: A 1% aqueous solution of triethanolamine polyoxyethylene tridecyl ether acetate was prepared in the same manner as in the case of triethanolamine octyl sulfate above, except that a 5% aqueous solution of sodium polyoxyethylene tridecyl ether acetate (manufactured by Sanyo Chemical Industries, Ltd., trade name "Viewlite ECA") was used.
Monoethanolamine tridecyl sulfate: A 1% aqueous solution of monoethanolamine tridecyl sulfate was prepared in the same manner as for monoethanolamine decyl sulfate above, except that a 5% aqueous solution of sodium tridecyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "1-sodium tridecyl sulfate") was used.
Ammonium tridecyl sulfate: A 5% aqueous solution of sodium tridecyl sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "1-sodium tridecyl sulfate") was treated with a strong cation ion exchange resin (Merck type I) to remove sodium, and then the pH was adjusted to 7 with ammonia (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name "ammonia water") and diluted with pure water to prepare a 1% aqueous solution of ammonium tridecyl sulfate, which was then used.
<Organic Acid>
・Maleic acid: FUJIFILM Wako Pure Chemical Industries, Ltd. ・Malic acid: FUJIFILM Wako Pure Chemical Industries, Ltd. ・Citric acid: FUJIFILM Wako Pure Chemical Industries, Ltd. ・Acetic acid: FUJIFILM Wako Pure Chemical Industries, Ltd. <Inorganic acid>
Phosphoric acid: Fujifilm Wako Pure Chemical Industries, product name "phosphoric acid"
Sulfuric acid: FUJIFILM Wako Pure Chemical Industries, Ltd., product name "sulfuric acid" (10% aqueous solution)
Nitric acid: Tokyo Chemical Industry Co., Ltd., product name "Nitric Acid" (67% aqueous solution)
<Basic Compound>
Tetraethylammonium hydroxide: manufactured by Tokyo Chemical Industry Co., Ltd., product name "Tetraethylammonium Hydroxide (10% in Water)"
Tetrabutylammonium hydroxide: manufactured by Tokyo Chemical Industry Co., Ltd., product name "Tetrabutylammonium Hydroxide (40% in Water)"
<Amine>
Aminoethanol: Fujifilm Wako Pure Chemical Industries, Ltd., product name "2-aminoethanol"
Triethanolamine: trade name "Triethanolamine" manufactured by Tokyo Chemical Industry Co., Ltd.
<Water-soluble polymer>
Polyacrylic acid: Toagosei Co., Ltd., product name "Jurimer AC-10L"
Polymaleic acid: NOF Corp., product name "Nonpol PMA-50W"
Polystyrene sulfonic acid: manufactured by Alfa Aesar, trade name "Poly(styrene sulfonic acid), sodium salt, M.W. 70,000"
Polyvinyl alcohol: Nippon Vinyl Acetate & Poval Co., Ltd., product name "PXP-05"
Polyethylene glycol: Fujifilm Wako Pure Chemical Industries, Ltd., product name "Polyethylene glycol 400"
<Amino acids>
Histidine: Fujifilm Wako Pure Chemical Industries, Ltd., product name "L-histidine"
Dodecylaminoethylaminoethylglycine: Sanyo Chemical Industries, Ltd., product name "Revon S"
L-(+)-Lysine: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name "L-lysine monohydrochloride"

As is clear from Tables 1 to 3 above, the use of the semiconductor cleaning compositions according to Examples 1 to 22, in which the value of MA/MB, which indicates the mass balance between compound (A) and compound (B), is within a specified range, is useful for reducing surface defects and suppressing damage when treating a surface to be treated having a silicon nitride film or silicon oxide film. From this, it is presumed that the use of the semiconductor cleaning composition according to the present invention can suppress damage caused by corrosion to wiring boards on which silicon nitride or silicon oxide is exposed, and can efficiently remove contamination from the surface of the object to be treated.

The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the present invention includes configurations that are substantially the same as those described in the embodiments (for example, configurations with the same functions, methods, and results, 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. The present invention also includes configurations that achieve the same effects as the configurations described in the embodiments, or that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

10...base, 12...insulating film, 14...barrier metal film, 16...wiring metal film, 20...wiring recess, 100...object to be processed, 200...wiring board

Claims (6)

A compound (A) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 8 to 12 carbon atoms,
and a compound (B) having a functional group represented by the following general formula (1) or (2) and an alkyl group having 13 to 18 carbon atoms,
The semiconductor cleaning composition, wherein the content of the compound (A) is MA (mass%) and the content of the compound (B) is MB (mass%), and MA/MB= 1.0 to 15 .
-SO ₃ ^- M ⁺ ...(1)
-COO ^- M ⁺ ...(2)
(In the above formulas (1) and (2), M ⁺ represents a monovalent cation.) The semiconductor cleaning composition according to claim 1, wherein in the above general formula (1) or (2), M ⁺ is a cation represented by the following general formula (3):

(In the above formula (3), ^R1 to ^R4 each independently represent a hydrogen atom or an organic group.) The semiconductor cleaning composition according to claim 1 or 2, further comprising an organic acid. The semiconductor cleaning composition according to any one of claims 1 to 3, having a pH of 2 to 7. A method for cleaning a semiconductor substrate, comprising a step of treating a wiring substrate on which at least one of silicon oxide and silicon nitride is exposed, with a semiconductor cleaning composition according to any one of claims 1 to 4. A method for cleaning a semiconductor substrate, comprising a step of treating the semiconductor substrate with the semiconductor cleaning composition according to any one of claims 1 to 4 after chemical mechanical polishing of the semiconductor substrate.

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