WO2025005092A1 - Treatment solution, method for treating object, and method for producing semiconductor device - Google Patents

Abstract

The present invention provides a treatment solution that, when the treatment solution is applied to an object having a copper surface which has been subjected to chemical-mechanical polishing treatment, causes little corrosion of copper and is excellent in ability to remove an organic residue on the copper surface. The present invention also provides a method for treating an object using the treatment solution, and a method for producing a semiconductor device using the treatment solution.　A treatment solution according to the present invention comprises an anionic polymer, a phosphonic acid compound, and hydroxyl-group-containing carboxylic acid, wherein the mass ratio of the phosphonic acid compound content to the anionic polymer content is 0.1-1000, and the pH is 0.1-7.0. The treatment solution is used in a semiconductor production process.

Description

Treatment liquid, method for treating object, and method for manufacturing semiconductor device

The present invention relates to a processing liquid, a processing method for an object, and a manufacturing method for a semiconductor device.

Semiconductor elements are manufactured by forming a resist film on a laminate having a metal film, which serves as the wiring material on a substrate, an etching stop layer, and an interlayer insulating layer, and then carrying out a photolithography process. In the photolithography process, a method is widely known in which a processing liquid that dissolves metals and/or organic substances is used to etch or remove foreign matter from the substrate surface.

In the manufacture of semiconductor elements, a chemical mechanical polishing (CMP) process may be performed to planarize a semiconductor substrate surface having a metal wiring film, a barrier metal, an insulating film, and the like, using a polishing slurry containing abrasive particles (e.g., silica, alumina, and the like).
In the CMP process, metal components derived from the polishing particles used in the CMP process, the polished wiring metal film and/or the barrier metal, etc., tend to remain on the polished semiconductor substrate surface. For this reason, after the CMP process, a step of removing these residues using a treatment liquid is generally carried out.

As a treatment liquid used in the cleaning process, for example, Patent Document 1 discloses "a water-based formulation having choline hydroxide together with a polymer selected from the group consisting of an acrylamide-methyl-propanesulfonate polymer, an acrylic acid-2-acrylamido-2-methylpropanesulfonic acid copolymer, and mixtures thereof, and a quaternary ammonium hydroxide having more than 4 carbon atoms or a non-acetylenic surfactant as a post-CMP cleaning formulation."

JP 2011-040722 A

The inventors of the present invention have investigated the removability of residues present on the copper surface of a target object after CMP processing using the post-CMP cleaning formulation described in Patent Document 1, and have found that it is difficult to simultaneously inhibit corrosion of the copper surface and remove organic residues from the copper surface.

Therefore, an object of the present invention is to provide a treatment liquid which, when applied to an object having a copper surface that has been subjected to chemical mechanical polishing, causes little corrosion of copper and is excellent in removing organic residues from the copper surface.
Another object of the present invention is to provide a method for treating an object using the treatment liquid, and a method for manufacturing a semiconductor device.

　As a result of extensive research into solving the above problems, the inventors have discovered that the problems can be solved by the following configuration.

[1] An anionic polymer;
A phosphonic acid compound,
and a hydroxyl-containing carboxylic acid,
a mass ratio of the content of the phosphonic acid compound to the content of the anionic polymer is 0.1 to 1000;
A processing solution used in semiconductor manufacturing processes, having a pH of 0.1 to 7.0.
[2] The treatment solution according to [1], wherein the hydroxyl group-containing carboxylic acid is selected from the group consisting of citric acid, malic acid, tartaric acid, glycolic acid, lactic acid, tartronic acid, glyceric acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, γ-hydroxybutyric acid, citramalic acid, isocitric acid, leucic acid, mevalonic acid, pantoic acid, ricinoleic acid, ricineraidic acid, cerebronic acid, quinic acid, shikimic acid, salicylic acid, creosote acid, vanillic acid, syringic acid, pyrocatechuic acid, resorcylic acid, protocatechuic acid, gentisic acid, orselliic acid, gallic acid, mandelic acid, benzilic acid, atrolactic acid, mellotic acid, phloretic acid, coumaric acid, umbellic acid, caffeic acid, ferulic acid, and sinapic acid.
[3] The treatment liquid according to [1] or [2], wherein the phosphonic acid compound is selected from the group consisting of etidronic acid, nitrilotris(methylene phosphonic acid), ethylenediaminetetramethylene phosphonic acid, and 2-phosphonobutane-1,2,4-tricarboxylic acid.
[4] The treatment liquid according to any one of [1] to [3], wherein the anionic polymer is selected from the group consisting of polyacrylic acid, polystyrenesulfonic acid, polyvinylsulfonic acid, poly(2-acrylamido-2-methyl-1-propanesulfonic acid), 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, polyvinylphosphonic acid, poly(N-vinylacetamide), and styrenesulfonic acid-acrylic acid-vinylphosphonic acid copolymer.
[5] The treatment liquid according to any one of [1] to [4], wherein the anionic polymer does not have a repeating unit derived from an acrylamide-based monomer.
[6] The treatment liquid according to any one of [1] to [5], wherein a mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer is 10 or more.
[7] The treatment liquid according to any one of [1] to [6], wherein a mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer is 100 or more.
[8] The treatment liquid according to any one of [1] to [7], wherein a mass ratio of the content of the anionic polymer to the total solid content of the treatment liquid is 0.0001 to 0.1.
[9] The treatment liquid according to any one of [1] to [8], further comprising an anionic surfactant selected from the group consisting of sulfonic acid surfactants, carboxylic acid surfactants, and phosphate ester surfactants.
[10] The treatment liquid according to [9], wherein the anionic surfactant is a sulfonic acid surfactant having an alkyl chain with 6 or more carbon atoms.
[11] The treatment liquid according to any one of [1] to [10], which is used for cleaning an object that has been subjected to a chemical mechanical polishing process.
[12] The treatment solution according to [11], wherein the object has a copper surface that has been subjected to a chemical mechanical polishing treatment, and the treatment solution is used to clean the copper surface.
[13] The treatment liquid according to any one of [1] to [12], which is diluted with a diluent containing water.
[14] The treatment liquid according to any one of [1] to [13], which does not contain a quaternary ammonium salt.
[15] A method for treating an object, comprising a step of contacting the object that has been subjected to chemical mechanical polishing with the treatment liquid according to any one of [1] to [14].
[16] A method for manufacturing a semiconductor device, comprising the method for treating an object according to [15].

According to the present invention, a treatment liquid can be provided which, when applied to an object having a copper surface that has been subjected to chemical mechanical polishing, causes little corrosion of copper and is excellent in removing organic residues from the copper surface.
The present invention also provides a method for treating an object using the treatment liquid, and a method for manufacturing a semiconductor device.

The present invention will be described in detail below.
The following description of the configuration may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment.

The following explains the meaning of each description in this specification.

In this specification, a numerical range expressed using "to" means a range that includes the numerical values before and after "to" as the lower and upper limits.
In this specification, the term "total solid content" refers to the total mass of all components contained in the treatment liquid other than water and solvents such as organic solvents.
In this specification, when two or more types of a component are present, the "content" of the component means the total content of those two or more components.
Unless otherwise specified, the compounds described herein may contain structural isomers, optical isomers, and isotopes. In addition, the structural isomers, optical isomers, and isotopes may be contained alone or in combination of two or more kinds.

In this specification, when there are a plurality of substituents, linking groups, etc. (hereinafter referred to as "substituents, etc.") represented by specific symbols, or when a plurality of substituents, etc. are simultaneously specified, it means that the respective substituents, etc. may be the same or different from each other. This also applies to the specification of the number of substituents, etc.
The bonding direction of the divalent group described in this specification is not limited unless otherwise specified. For example, when Y is -COO- in a compound represented by the formula "X-Y-Z", Y may be -CO-O- or -O-CO-. In addition, the above compound may be "X-CO-O-Z" or "X-O-CO-Z".

In this specification, "(meth)acrylic" is a general term including acrylic and methacrylic, and means "at least one of acrylic and methacrylic." Similarly, "(meth)acrylic acid" means "at least one of acrylic acid and methacrylic acid."

In this specification, unless otherwise specified, the molecular weight of a compound having a molecular weight distribution is the weight average molecular weight.
In this specification, when the polymers used are commercially available and have catalog values (nominal values published by the manufacturer) for the weight average molecular weight (Mw), number average molecular weight (Mn), and polydispersity (also referred to as molecular weight distribution) (Mw/Mn) of the polymer, the catalog values are used.
When there are no catalog values or the like, or when the weight average molecular weight (Mw), number average molecular weight (Mn), and polydispersity (Mw/Mn) of a polymer are determined by measurement, the weight average molecular weight (Mw), number average molecular weight (Mn), and polydispersity (Mw/Mn) are measured by GPC (Gel Permeation Chromatography) using a GPC device (Shimadzu Corporation, Prominence UFLC) (eluent: phosphate buffer (pH = 7) and acetonitrile in a volume ratio of 9:1, flow rate (sample injection amount): 50 μL, column: Tosoh Corporation, TSK guardcolumn α + TSK gel α-6000 + TSK gel α-3000, column temperature: 40°C, flow rate: 1.0 mL/min, detector: differential refractive index detector (Refractive Index Detector) It is defined as a polystyrene equivalent value measured by a HPLC-MS/MS Detector). The above description of "TSK guard column α + TSK gel α-6000 + TSK gel α-3000" indicates that the above three types of columns were used in combination.

In this specification, "ppm" means "parts-per-million (10 ^-6 )" and "ppb" means "parts-per-billion (10 ^-9 )."
In this specification, 1 Å (angstrom) corresponds to 0.1 nm.

[Processing solution]
The treatment liquid of the present invention is used in a semiconductor manufacturing process, and contains an anionic polymer, a phosphonic acid compound, and a hydroxyl group-containing carboxylic acid, the mass ratio of the content of the phosphonic acid compound to the content of the anionic polymer being 0.1 to 1000, and the pH being 0.1 to 7.0.
The mechanism by which the treatment liquid of the present invention having the above-mentioned composition is able to solve the problems of the present invention is not entirely clear, but the present inventors speculate as follows.
The mechanism by which the effects are obtained is not limited by the following speculation. In other words, even if the effects are obtained by a mechanism other than the following, it is included in the scope of the present invention.

The treatment solution of the present invention is characterized in that it contains an anionic polymer. Hydroxyl-containing carboxylic acid and acid compounds such as phosphonic acid compounds are effective in removing organic residues containing copper generated after CMP treatment, but they corrode copper.
The present inventors have now investigated the composition of the treatment solution and have surprisingly found that adding an anionic polymer to the treatment solution containing the above-mentioned hydroxyl-containing carboxylic acid and phosphonic acid compound not only inhibits copper corrosion but also has an effect on the removal of organic residues.

Each component contained in the processing liquid of the present invention will be described in detail below.
In this specification, when the present invention is applied to an object having a copper surface that has been subjected to a chemical mechanical polishing process, at least one of the effects of reducing copper corrosion and being excellent in the removability of organic residues on the copper surface is obtained, this is also referred to as "the effect of the present invention being superior."

[Anionic polymer]
The treatment liquid of the present invention contains an anionic polymer. The anionic polymer is a polymer containing a functional group (hereinafter also referred to as an "anionic functional group") that exhibits anionic properties when dissolved in water, such as a carboxy group. The anionic polymer is preferably a polymer containing a repeating unit (hereinafter also referred to as "repeating unit A") having an anionic functional group.
As described in detail later, the anionic polymer may have a repeating unit other than the repeating unit A, but is preferably a polymer consisting only of the repeating unit A. The anionic polymer may have two or more kinds of repeating units A.
When the anionic polymer has two or more kinds of repeating units, the polymerization mode is not particularly limited, and the polymer may be a graft copolymer, a block copolymer, or the like.

<Repeating unit A>
The anionic functional group contained in the repeating unit A is not particularly limited, and examples thereof include an acid group or a salt thereof.
Specific examples of the acid group include a carboxy group, a sulfonic acid group, a phosphonic acid group, and a phenolic hydroxyl group.
Salts of acid groups include, for example, ammonium, potassium, sodium, and lithium salts.
The number of acid groups or salts thereof contained in the repeating unit A is not particularly limited, but is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2.

In terms of achieving better effects of the present invention, the anionic polymer is preferably a polymer containing a repeating unit A selected from the group consisting of a repeating unit having a carboxy group or a salt thereof, and a repeating unit having a sulfonic acid group or a salt thereof, more preferably a polymer consisting only of a repeating unit A selected from the group consisting of a repeating unit having a carboxy group or a salt thereof, and a repeating unit having a sulfonic acid group or a salt thereof, and even more preferably a polymer consisting only of a repeating unit A having a carboxy group, or a polymer consisting only of a repeating unit A having a sulfonic acid group.

Examples of the repeating unit A include repeating units derived from a compound having an acid group or a salt thereof, and an ethylenically unsaturated group.
Specific examples of the acid group or a salt thereof are as described above.
The ethylenically unsaturated group is a functional group having an ethylenically unsaturated bond. Examples of the ethylenically unsaturated group include an aromatic vinyl group, an acryloyloxy group (CH ₂ ═CH-COO-), a methacryloyloxy group (CH ₂ ═CCH ₃ -COO-), an acrylamide group (CH ₂ ═CH-CONH-), a methacrylamide group (CH ₂ ═CCH ₃ -CONH-), a maleimide group, a vinyl group, and a vinyl ether group.
Of the ethylenically unsaturated groups, aromatic vinyl groups, acryloyloxy groups, methacryloyloxy groups, acrylamide groups, and vinyl groups are preferred, and as the aromatic vinyl group, a styryl group is preferred.
The repeating unit A may be a repeating unit derived from a compound having an acrylamide group (acrylamide-based monomer). However, when the anionic polymer does not have a repeating unit derived from an acrylamide-based monomer, this is preferred because there is little change in the physical properties of the treatment liquid over time and little corrosion of copper even when a copper-containing object is treated with the treatment liquid after storage over time.

The repeating unit A is preferably a repeating unit represented by formula (a).

In formula (a), R ^a1 , R ^a2 and R ^a3 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an acid group or a salt thereof.
L ^a represents a single bond or a (k+1)-valent linking group.
A represents an acid group or a salt thereof.
k represents an integer of 1 to 4.
When a plurality of acid groups or salts thereof are present in formula (a), the plurality of acid groups or salts thereof may be the same or different.

R ^a1 , R ^a2 and R ^a3 are preferably a hydrogen atom, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), a methyl group, an ethyl group, a carboxy group or a salt thereof, and more preferably a hydrogen atom, a methyl group, or a carboxy group or a salt thereof.
Among these, it is preferable that one of R ^a1 , R ^a2 and R ^a3 represents a hydrogen atom, a methyl group, a carboxy group or a salt thereof, and the remaining two each represent a hydrogen atom.

The (k+1)-valent linking group represented by L ^a is not particularly limited as long as it is a group having a valence corresponding to the number of A, and examples include di- to pentavalent aliphatic hydrocarbon groups which may have a substituent, di- to pentavalent aromatic hydrocarbon groups which may have a substituent, di- to pentavalent aromatic heterocyclic groups which may have a substituent, -O-, -CO-, -SO ₂ -, -NR ^L -, -N<, and groups formed by combining these. R ^L represents a hydrogen atom or a monovalent aliphatic hydrocarbon group.
The aliphatic hydrocarbon group may be linear, branched, or cyclic.
k is preferably 1, and in that case, examples of the divalent linking group represented by L ^a include a divalent aliphatic hydrocarbon group, a divalent aromatic hydrocarbon group, a divalent aromatic heterocyclic group, -O-, -CO-, -SO ₂ -, -NR ^L -, and groups formed by combining these, and among these, a single bond, -CO-O-, -CO-NH-, an alkylene group having 1 to 5 carbon atoms, a phenylene group, and groups formed by combining these are preferred.

The acid group or salt thereof represented by A includes a carboxy group, a sulfonic acid group, a phosphonic acid group, a phenolic hydroxyl group, and salts thereof. A carboxy group or a salt thereof, or a sulfonic acid group or a salt thereof is preferred, and a carboxy group or a salt thereof is more preferred.

Examples of repeating unit A include repeating units derived from compounds selected from the group consisting of acrylic acid, maleic acid, itaconic acid, vinyl acetic acid, allyl acetic acid, fumaric acid, p-styrenesulfonic acid, vinylsulfonic acid, 2-acrylamido-2-methyl-1-propanesulfonic acid, vinylphosphonic acid, and N-vinylacetamide.

The content of repeating unit A is not particularly limited, but is preferably 50 to 100 mol %, more preferably 75 to 100 mol %, and even more preferably 90 to 100 mol %, of the total repeating units of the anionic polymer.

<Repeating Unit B>
The anionic polymer may include a repeat unit B which is different from the repeat unit A.
The repeating unit B is not particularly limited, and examples thereof include repeating units derived from a compound selected from the group consisting of alkylene oxide compounds, aromatic vinyl compounds, (meth)acrylic acid alkyl ester compounds which may have a hydroxyl group, unsaturated alcohol compounds, aliphatic conjugated diene compounds, vinyl cyanide compounds, and amide compounds having a polymerizable double bond.

Examples of the aromatic vinyl compounds include styrene, α-methylstyrene, vinyltoluene, and p-methylstyrene.

The content of repeating unit B is not particularly limited, but is preferably 0.1 to 50 mol %, more preferably 1 to 25 mol %, and even more preferably 1 to 15 mol %, based on the total repeating units of the anionic polymer.

The anionic polymer is preferably selected from the group consisting of polyacrylic acid, polystyrene sulfonic acid, polyvinyl sulfonic acid, poly(2-acrylamido-2-methyl-1-propanesulfonic acid), 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, polyvinylphosphonic acid, poly(N-vinylacetamide), and styrenesulfonic acid-acrylic acid-vinylphosphonic acid copolymer.

The weight average molecular weight of the anionic polymer is preferably 500 to 80,000, more preferably 1,000 to 30,000, even more preferably 2,000 to 20,000, and particularly preferably 4,000 to 10,000.

The anionic polymer may be used alone or in combination of two or more kinds.
The content of the anionic polymer is preferably from 0.0001 to 10.0% by mass, more preferably from 0.001 to 1.0% by mass, and even more preferably from 0.01 to 1.0% by mass, based on the total mass of the treatment liquid.
The mass ratio of the content of the anionic polymer to the total solid content of the treatment liquid is preferably from 0.00001 to 1.0, more preferably from 0.0001 to 0.1, and even more preferably from 0.001 to 0.05.

[Phosphonic acid compounds]
The treatment liquid of the present invention contains a phosphonic acid compound. The phosphonic acid compound refers to a compound that contains at least one phosphonic acid group (a group formed by removing one hydrogen atom on the phosphorus atom from phosphonic acid) in the molecule, and is a compound different from the above-mentioned anionic polymer.
The number of phosphonic acid groups in the phosphonic acid compound is preferably 2 to 8, more preferably 2 to 4, and even more preferably 2 or 3.
The phosphonic acid compound is preferably a low molecular weight compound having no repeating units. In other words, the phosphonic acid compound is preferably a compound having no repeating units (corresponding to a low molecular weight compound) rather than a polymeric compound having multiple repeating units.
The molecular weight of the phosphonic acid compound is preferably 50 to 1,000, more preferably 100 to 600, and even more preferably 100 to 450.

The phosphonic acid compound is preferably an organic acid. That is, the phosphonic acid compound is preferably a phosphonic acid-based organic acid. The number of carbon atoms (carbon number) contained in the phosphonic acid compound is preferably 1 to 12, more preferably 1 to 10, and even more preferably 1 to 8.
Examples of the phosphonic acid-based organic acid include aliphatic phosphonic acid-based organic acids and aminophosphonic acid-based organic acids.
The aliphatic phosphonic acid-based organic acid may further have a hydroxyl group in addition to the phosphonic acid group and the aliphatic group.
Examples of phosphonic acid-based organic acids include ethylidene diphosphonic acid, 1-hydroxyethylidene-1,1'-diphosphonic acid (etidronic acid, HEDP), nitrilotris(methylene phosphonic acid) (NTMP), ethylenediaminetetra(methylene phosphonic acid) (EDTMP), 2-phosphonobutane-1,2,4-tricarboxylic acid, diethylenetriaminepenta(methylene phosphonic acid) (DEPPO), 1-hydroxypropylidene-1,1'-diphosphonic acid, 1-hydroxybutylidene-1,1'-diphosphonic acid, ethylaminobis(methylene phosphonic acid), dodecylaminobis(methylene Examples of suitable phosphonic acids include 1,3-propylenediamine bis(methylene phosphonic acid), ethylenediamine tetra(ethylene phosphonic acid), 1,3-propylenediamine tetra(methylene phosphonic acid) (PDTMP), 1,2-diaminopropane tetra(methylene phosphonic acid), 1,6-hexamethylenediamine tetra(methylene phosphonic acid), diethylenetriamine penta(ethylene phosphonic acid), triethylenetetramine hexa(methylene phosphonic acid), and triethylenetetramine hexa(ethylene phosphonic acid).
The phosphonic acid compound is preferably selected from the group consisting of etidronic acid, nitrilotris(methylene phosphonic acid), ethylenediaminetetramethylene phosphonic acid, and 2-phosphonobutane-1,2,4-tricarboxylic acid.

In addition to the above, examples of the phosphonic acid-based organic acid include the compounds described in paragraphs [0026] to [0036] of WO 2018/020878, the contents of which are incorporated herein by reference.
In addition, some commercially available phosphonic acid organic acids contain water, such as distilled water, deionized water, and ultrapure water, in addition to the phosphonic acid organic acid, and such phosphonic acid organic acids containing water may be used.

The phosphonic acid compounds may be used alone or in combination of two or more.
The content of the phosphonic acid compound is preferably from 0.0001 to 10% by mass, more preferably from 0.001 to 5% by mass, and even more preferably from 0.01 to 1% by mass, based on the total mass of the treatment liquid.
The mass ratio of the content of the phosphonic acid compound to the total solid content of the treatment liquid is preferably from 0.001 to 10, more preferably from 0.01 to 1.0, and even more preferably from 0.01 to 0.1.

The mass ratio of the phosphonic acid compound content to the anionic polymer content is not particularly limited as long as it is 0.1 to 1000, but is preferably 0.1 to 500, more preferably 0.1 to 50, and even more preferably 0.1 to 10.

[Hydroxyl-containing carboxylic acid]
The treatment liquid of the present invention contains a hydroxyl-containing carboxylic acid. The hydroxyl-containing carboxylic acid refers to a compound having at least one hydroxyl group and at least one carboxyl group in the molecule, and is a compound different from the above-mentioned anionic polymer.
The number of carboxy groups in the hydroxyl-containing carboxylic acid is preferably 2 to 8, more preferably 2 to 4, and even more preferably 2 to 3.
The number of hydroxyl groups in the hydroxyl-containing carboxylic acid is preferably 1 to 5, and more preferably 1 to 3.
The hydroxyl-containing carboxylic acid is preferably a low molecular weight compound having no repeating units.
The molecular weight of the hydroxyl group-containing carboxylic acid is preferably 50 to 1,000, more preferably 100 to 600, and even more preferably 100 to 450.
The hydroxyl group-containing carboxylic acid preferably has 1 to 12 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 8 carbon atoms.

The hydroxyl-containing carboxylic acid is preferably an α-hydroxycarboxylic acid (a carboxylic acid having a hydroxyl group on the carbon atom to which the carboxyl group is bonded).
The hydroxyl group-containing carboxylic acid may be either an aliphatic hydroxycarboxylic acid or an aromatic hydroxycarboxylic acid, but is preferably an aliphatic hydroxycarboxylic acid, and more preferably an aliphatic hydroxycarboxylic acid having 1 to 15 carbon atoms.

As the carboxylic acid-based organic acid, a compound represented by formula (D) is preferred, and a compound represented by formula (D1) is more preferred.

In formula (D), ^Ld represents a divalent linking group having a hydroxyl group.
Examples of the divalent linking group include an ether group, a carbonyl group, an ester group, a thioether group, -SO ₂ -, -NT-, a divalent hydrocarbon group (e.g., an alkylene group, an alkenylene group, an alkynylene group, and an arylene group), and a combination thereof. T represents a hydrogen atom or a substituent. The divalent linking group may further have a substituent in addition to the hydroxyl group.
Examples of the substituent include an alkyl group, an aryl group, a carboxy group, an amino group, and a halogen atom.
Of these, ^Ld is preferably a divalent hydrocarbon group having a hydroxyl group, more preferably an alkylene group having a hydroxyl group.
The divalent linking group preferably has 1 to 5 hydroxyl groups, and more preferably has 1 to 3 hydroxyl groups.
The divalent linking group preferably has 1 to 15 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 5 carbon atoms.

In formula (D1), R ^d1 and R ^d2 each independently represent a hydrogen atom, a hydroxyl group, or a carboxyl group, and n represents an integer of 1 to 5.
However, when n is 1, at least one of R ^d1 and R ^d2 represents a hydroxyl group, and when n is 2 or more, at least one of a plurality of R ^d1s and R ^d2s represents a hydroxyl group.

The total number of carboxy groups contained in the compound represented by formula (D1) is preferably 2 to 8, more preferably 2 to 4, and even more preferably 2 or 3.
The total number of hydroxyl groups contained in the compound represented by formula (D1) is preferably 1 to 5, and more preferably 1 to 3.

n represents an integer of 1 to 5.
n is preferably an integer of 1 to 4, and more preferably an integer of 1 to 3.

The hydroxyl group-containing carboxylic acid is preferably selected from the group consisting of citric acid, malic acid, tartaric acid, gluconic acid, heptonic acid, glycolic acid, lactic acid, tartronic acid, glyceric acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, γ-hydroxybutyric acid, citramalic acid, isocitric acid, leucic acid, mevalonic acid, pantoic acid, ricinoleic acid, ricineraidic acid, cerebronic acid, quinic acid, shikimic acid, phenyllactic acid, hydroxyphenyllactic acid, salicylic acid, creosote acid, vanillic acid, syringic acid, pyrocatechuic acid, resorcylic acid, protocatechuic acid, gentisic acid, orselliic acid, gallic acid, mandelic acid, benzilic acid, atrolactic acid, mellitic acid, phloretic acid, coumaric acid, umbellic acid, caffeic acid, ferulic acid, and sinapic acid.

The hydroxyl group-containing carboxylic acids may be used alone or in combination of two or more.
The content of the hydroxyl group-containing carboxylic acid is preferably from 0.01 to 60% by mass, more preferably from 0.1 to 50% by mass, and even more preferably from 1 to 30% by mass, based on the total mass of the treatment liquid.
The mass ratio of the content of the hydroxyl group-containing carboxylic acid to the total solid content of the treatment liquid is preferably from 0.001 to 10, and more preferably from 0.1 to 1.0.

The mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer is not particularly limited, but is preferably 1 to 12,000, more preferably 10 to 1,000, even more preferably 10 to 250, and particularly preferably 100 to 250.

[Anionic Surfactants]
The treatment liquid of the present invention may contain an anionic surfactant, and preferably further contains an anionic surfactant selected from the group consisting of sulfonic acid surfactants, carboxylic acid surfactants, and phosphate ester surfactants.
The anionic surfactant is a compound different from the above-mentioned components.
The anionic surfactant is preferably a low molecular weight compound that does not have a repeating unit.
The molecular weight of the anionic surfactant is preferably from 50 to 1,000, more preferably from 100 to 600, and even more preferably from 100 to 450.

Anionic surfactants often have at least one hydrophobic group selected from the group consisting of an aliphatic hydrocarbon group, an aromatic hydrocarbon group, and combinations thereof.
When the hydrophobic group contains an aromatic hydrocarbon group, the carbon number of the hydrophobic group in the anionic surfactant is preferably 6 or more, and more preferably 10 or more. When the hydrophobic group does not contain an aromatic hydrocarbon group and is composed only of an aliphatic hydrocarbon group, the carbon number of the hydrophobic group in the anionic surfactant is preferably 9 or more, more preferably 13 or more, and even more preferably 16 or more.
The upper limit of the number of carbon atoms in the hydrophobic group of the anionic surfactant is preferably 20 or less, and more preferably 18 or less.
As the anionic surfactant, among others, a sulfonic acid surfactant having an alkyl chain with 6 or more carbon atoms is preferable.

(Sulfonic acid surfactant)
Examples of sulfonic acid surfactants include alkyl sulfonic acids, alkyl benzene sulfonic acids, alkyl naphthalene sulfonic acids, alkyl diphenyl ether disulfonic acids, alkyl methyl taurines, sulfosuccinic acid diesters, polyoxyalkylene alkyl ether sulfonic acids, and salts thereof.
More specifically, the sulfonic acid surfactants include lauryl sulfonic acid, dodecylbenzene sulfonic acid, alkyl diphenyl ether disulfonic acid (the alkyl group preferably has 12 to 14 carbon atoms), and naphthalene sulfonic acid formalin condensate.

(Carboxylic acid surfactant)
Examples of the carboxylic acid surfactant include alkyl carboxylic acids, alkenyl carboxylic acids, alkyl benzene carboxylic acids, polyoxyalkylene alkyl ether carboxylic acids, anhydrides thereof, and salts thereof.
More specifically, the carboxylic acid surfactant includes trideceth-4 carboxylic acid, dodecenyl succinic anhydride, lauric acid, myristic acid, palmitic acid, stearic acid, polyoxyethylene lauryl ether acetic acid, and polyoxyethylene tridecyl ether acetic acid.

(Phosphate ester surfactant)
Examples of phosphate surfactants include alkyl phosphate esters and polyoxyalkylene alkyl ether phosphate esters, as well as salts thereof.
The phosphate esters and polyoxyalkylene alkyl ether phosphate esters usually include both monoesters and diesters, but either the monoester or the diester can be used alone.
Examples of salts of the phosphate ester surfactants include sodium salts, potassium salts, ammonium salts, and organic amine salts.

Examples of phosphate ester surfactants include the compounds described in paragraphs [0012] to [0019] of JP 2011-040502 A, the contents of which are incorporated herein by reference.

The anionic surfactant may be used alone or in combination of two or more kinds.
The content of the anionic surfactant is preferably from 0.001 to 8.0% by mass, more preferably from 0.005 to 5.0% by mass, and even more preferably from 0.01 to 3.0% by mass, based on the total mass of the treatment liquid.
The mass ratio of the content of the hydroxyl group-containing carboxylic acid to the total solid content of the treatment liquid is preferably from 0.0001 to 1.0, and more preferably from 0.001 to 0.1.

〔water〕
The treatment liquid may contain water as a solvent.
The type of water used in the treatment solution may be any type that does not adversely affect the semiconductor substrate, and may be distilled water, deionized water (DI: De Ionized) water, or pure water (ultrapure water). Pure water (ultrapure water) is preferred because it contains almost no impurities and has less effect on the semiconductor substrate during the manufacturing process of the semiconductor substrate.
The water content is preferably 1.0% by mass or more, more preferably 30.0% by mass or more, even more preferably 60.0% by mass or more, and particularly preferably 80.0% by mass or more, based on the total mass of the treatment liquid. The upper limit of the water content is preferably 99.99% by mass or less, more preferably 99.9% by mass or less, even more preferably 99.0% by mass or less, and particularly preferably 97.0% by mass or less, based on the total mass of the treatment liquid.

[Other ingredients]
The treatment liquid of the present invention may contain other components in addition to the above-mentioned components, such as a pH adjuster, an organic solvent, a preservative (antibacterial agent), a reducing agent, and a dissolved gas.
It is also preferable that the processing solution of the present invention does not contain a quaternary ammonium salt.
The other ingredients will be described below.

<pH Adjuster>
The treatment liquid of the present invention may contain a pH adjuster to adjust and maintain the pH of the treatment liquid of the present invention.
The pH adjuster is a basic compound or an acidic compound different from the components contained in the treatment liquid of the present invention described above, however, it is permissible to adjust the pH of the treatment liquid of the present invention by adjusting the amount of each component that can be contained in the treatment liquid of the present invention.

The basic compound is a compound that exhibits basicity (pH of more than 7.0) in an aqueous solution, and examples of such compounds include basic inorganic compounds.
Examples of basic inorganic compounds include amine compounds such as trishydroxymethylaminomethane, ammonia, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and alkaline earth metal hydroxides.

The acidic compound serving as the pH adjuster is a compound that exhibits acidity (pH less than 7.0) in an aqueous solution, and examples of such compounds include acidic inorganic compounds.
Examples of acidic inorganic compounds include hydrochloric acid, nitric acid, nitrous acid, sulfurous acid, phosphoric acid, boric acid, carbonic acid, hypophosphorous acid, phosphorous acid, and hexafluorophosphoric acid.
The acidic compound used as the pH adjuster may be a salt of an acidic compound, so long as it becomes an acid or an acid ion (anion) in an aqueous solution.

The content of the pH adjuster can be selected according to the type and amount of other components, and the desired pH of the treatment liquid. For example, the content of the pH adjuster is preferably 0.0001 to 10 mass %, more preferably 0.001 to 8 mass %, and even more preferably 0.001 to 0.1 mass %, relative to the total mass of the treatment liquid.

<Organic solvent>
The treatment liquid of the present invention may contain an organic solvent. Examples of the organic solvent include known organic solvents, such as alcohol-based solvents, glycol-based solvents, glycol ether-based solvents, and ketone-based solvents.
The organic solvent is preferably miscible with water in any ratio.
As the organic solvent, for example, the compounds exemplified in paragraphs [0135] to [140] of WO 2022/044893 can be used, the contents of which are incorporated herein by reference.

<Preservatives>
The treatment liquid of the present invention may contain a preservative.
The preservative is a compound different from the components contained in the processing solution of the present invention described above.
Examples of preservatives include benzoic acid, sodium benzoate, salicylic acid, propionic acid, isopropyl parahydroxybenzoate, isobutyl parahydroxybenzoate, ethyl parahydroxybenzoate, methyl parahydroxybenzoate, butyl parahydroxybenzoate, propyl parahydroxybenzoate, sodium sulfite, sodium hyposulfite, potassium metabisulfite, sorbic acid, potassium sorbate, sodium dehydroacetate, thujaplicin, Aralia udo extract, Styrax japonica extract, Artemisia capillaris extract, oolong tea extract, white milt protein extract, enzymatically hydrolyzed Job's tears extract, tea catechins, apple polyphenols, pectin hydrolyzates, chitosan, lysozyme, and ε-polylysine.
Among these, the preservative is preferably benzoic acid, sorbic acid, salicylic acid, or propionic acid.

The preservative content is preferably 0.0001 to 10.0% by mass, more preferably 0.0001 to 1.0% by mass, and even more preferably 0.0001 to 0.1% by mass, based on the total mass of the treatment solution.

<Reducing Agent>
The processing liquid of the present invention may contain a reducing agent.
The reducing agent is a compound having a reducing action and a function of reducing ^OH- ions or dissolved oxygen contained in the treatment liquid, and is also called an oxygen scavenger. The reducing agent functions as an anticorrosive agent that improves the corrosion prevention performance of the treatment liquid.
The reducing agent used in the treatment liquid is not particularly limited, but examples thereof include ascorbic acid compounds, catechol compounds, hydroxylamine compounds, hydrazide compounds, and reducing sulfur compounds.
Specific examples of ascorbic acid compounds, catechol compounds, hydroxylamine compounds, hydrazide compounds, and reducing sulfur compounds include the compounds described in paragraphs [0084] to [0093] of WO 2021/131452. The contents of these compounds are incorporated herein by reference.

<Dissolved gas>
The treatment liquid of the present invention may contain a dissolved gas. By setting the concentration of the dissolved gas in the treatment liquid within an appropriate range, it is possible to enhance the removability of residues.
The concentration of the dissolved gas is preferably 0.01 to 10 mg/L based on the total volume of the treatment liquid of the present invention.
The concentration of the dissolved gas is preferably 0.05 mg/L or more, more preferably 0.1 mg/L or more, based on the total volume of the treatment solution of the present invention, in terms of a more excellent residue removal effect, while it is preferably 7 mg/L or less, more preferably 4 mg/L or less, and even more preferably 1.5 mg/L or less, based on the total volume of the treatment solution of the present invention, in terms of a more excellent storage stability.

The dissolved gas is not particularly limited, but is preferably clean air. In this specification, "clean air" refers to air of Class 8 or lower (Class 8 or a smaller Class) in the ISO standard ISO 14644-1:2015.
The concentration of dissolved gas in the treatment liquid can be evaluated by measuring the concentrations of oxygen gas ( _O2 gas), nitrogen gas ( _N2 gas), and carbon dioxide gas ( _CO2 gas) and evaluating them as the sum of these values. The measurement method for oxygen gas, nitrogen gas, and carbon dioxide gas can be the treatment method described in paragraph [0020] of International Publication No. 2020/194978, the contents of which are incorporated herein by reference.

The concentration of the dissolved gas can be controlled by known methods, for example, the methods described in paragraphs [0019], [0052] to [0056], and [0060] to [0062] of WO 2020/194978, the contents of which are incorporated herein by reference.

<Abrasive particles>
The treatment liquid is preferably substantially free of abrasive particles.
The abrasive particles refer to particles contained in the polishing liquid used in the polishing process of the semiconductor substrate, and have an average primary particle size of 5 nm or more.
Examples of the abrasive particles include particles of inorganic solids such as silica (including colloidal silica and fumed silica), alumina, zirconia, ceria, titania, germania, manganese oxide, and silicon carbide; and particles of organic solids such as polystyrene, polyacrylic resin, and polyvinyl chloride.
"Substantially free of abrasive particles" means that the content of abrasive particles is less than 0.1% by mass, preferably 0.01% by mass or less, more preferably 0.001% by mass or less, based on the total mass of the treatment liquid. The lower limit is not particularly limited, and is 0% by mass.
The content of abrasive particles can be measured using a commercially available measuring device that uses a laser as a light source and is a liquid-borne particle measuring method based on light scattering.
The average primary particle diameter of particles such as abrasive particles is determined by measuring the particle diameters (equivalent circle diameters) of 1,000 primary particles arbitrarily selected from an image obtained using a transmission electron microscope TEM2010 (accelerating voltage 200 kV) manufactured by JEOL Ltd., and calculating the arithmetic mean of the particle diameters. The equivalent circle diameter is the diameter of a perfect circle having the same projected area as the projected area of the particle during observation.
A method for removing the abrasive particles from the treatment liquid includes, for example, a purification process such as filtering.

[Physical properties of processing solution]
<pH>
The pH of the treatment liquid is not particularly limited as long as it is 0.1 to 7.0, but is preferably 0.1 to 6.0, and more preferably 1.0 to 4.0. When the treatment liquid of the present invention is applied to an object having a copper surface that has been subjected to chemical mechanical polishing, the pH of the treatment liquid is preferably in the above range. When the treatment liquid of the present invention is applied to an object having a tungsten surface that has been subjected to chemical mechanical polishing, the pH of the treatment liquid is preferably 3.0 to 7.0, and more preferably 5.0 to 7.0.
The pH of the treatment solution can be measured by a method conforming to JIS Z8802-1984 using a known pH meter. The pH is measured at a temperature of 25°C.

<Metal content>
The content (measured as ion concentration) of metals (e.g., Fe, Co, Na, Cu, Mg, Mn, Li, Al, Cr, Ni, Zn, Sn, and Ag metal elements) contained as impurities in the treatment liquid is preferably 5 mass ppm or less, more preferably 1 mass ppm or less. In particular, the content of sodium atoms in the treatment liquid is preferably 1 mass ppm or less relative to the total mass of the treatment liquid.
In the manufacture of cutting-edge semiconductor devices, it is expected that a treatment solution with even higher purity will be required, so the content of the above metals is more preferably lower than 1 ppm by mass, that is, on the order of ppb by mass or less, particularly preferably 100 ppb by mass or less, and most preferably less than 10 ppb by mass. The lower limit is preferably 0.

Methods for reducing the metal content include, for example, performing purification processes such as distillation and filtration using an ion exchange resin or a filter at the stage of the raw materials used in producing the treatment liquid, or at the stage after the treatment liquid is produced.
Other methods for reducing the metal content include using a container that is less likely to elute impurities as a container for containing the raw materials or the produced treatment liquid, as described below, and lining the inner walls of pipes with a fluororesin to prevent metal components from eluting from the pipes during the production of the treatment liquid.

<Insoluble particles>
It is preferred that the treatment liquid be substantially free of insoluble particles.
The above-mentioned "insoluble particles" refer to particles of inorganic solids and organic solids, etc., which do not dissolve and ultimately exist as particles in the treatment liquid.
The above-mentioned "substantially free of insoluble particles" means that the treatment liquid is diluted 10,000 times with a solvent contained in the treatment liquid to prepare a composition for measurement, and the number of particles having a particle size of 40 nm or more contained in 1 mL of the composition for measurement is 40,000 or less. The number of particles contained in the composition for measurement can be measured in the liquid phase using a commercially available particle counter.
As commercially available particle counter devices, devices manufactured by Rion and PMS can be used. A representative device of the former is the KS-19F, and a representative device of the latter is the UltraChem 40. To measure larger coarse particles, devices such as the KS-42 series and LiQuilaz II S series can be used.
Examples of insoluble particles include particles of inorganic solids such as silica (including colloidal silica and fumed silica), alumina, zirconia, ceria, titania, germania, manganese oxide, and silicon carbide; and particles of organic solids such as polystyrene, polyacrylic resin, and polyvinyl chloride.
Methods for removing insoluble particles from the treatment liquid include, for example, purification treatments such as filtering.

<Coarse particles>
The treatment liquid may contain coarse particles, but it is preferable that the content of coarse particles is low.
The term "coarse particles" refers to particles whose diameter (particle size) when considered as a sphere is 1 μm or more.
The coarse particles contained in the treatment liquid include particles such as dust, dirt, organic solids, and inorganic solids that are contained as impurities in the raw materials, as well as particles such as dust, dirt, organic solids, and inorganic solids that are brought in as contaminants during the preparation of the treatment liquid, and which ultimately exist as particles in the treatment liquid without dissolving.

Regarding the content of coarse particles in the treatment liquid, the content of particles having a particle diameter of 1 μm or more per 1 mL of the treatment liquid is preferably 100 or less, more preferably 50 or less. The lower limit is preferably 0 or more, more preferably 0.01 or more per 1 mL of the treatment liquid.
The content of coarse particles present in the treatment liquid can be measured in the liquid phase using a commercially available measuring device that employs a light scattering liquid particle measuring method using a laser as a light source.
Examples of a method for removing coarse particles include a purification process such as filtering, which will be described later.

[Method of manufacturing the treatment liquid]
The processing solution can be produced by a known method, which will be described in detail below.

[Liquid preparation process]
The treatment liquid can be produced, for example, by mixing the above-mentioned components.
As a method for preparing the treatment liquid, for example, an anionic polymer, a phosphonic acid compound, a hydroxyl group-containing carboxylic acid, and an optional component as required are sequentially added to a container containing purified pure water, and then the mixture is stirred and mixed, and a pH adjuster is added as required to adjust the pH of the mixture, thereby preparing the treatment liquid. When each component is added to the container, it may be added all at once, or may be added in portions over several times.

The stirring device and stirring method used to prepare the treatment liquid may be a device known as a stirrer or disperser. Examples of stirrers include industrial mixers, portable stirrers, mechanical stirrers, and magnetic stirrers. Examples of dispersers include industrial dispersers, homogenizers, ultrasonic dispersers, and bead mills.

The mixing of the components in the preparation process of the treatment liquid, the purification process described below, and the storage of the produced treatment liquid are preferably carried out at 40°C or less, and more preferably at 30°C or less. The lower limit is preferably 5°C or more, and more preferably 10°C or more. By preparing, processing, and/or storing the treatment liquid within the above temperature range, the performance can be maintained stably for a long period of time.

<Refinification>
It is preferable to carry out a purification treatment in advance for one or more of the raw materials for preparing the treatment liquid. Examples of the purification treatment include known methods such as distillation, ion exchange, and filtration.
The degree of purification is preferably such that the purity of the raw material is 99% by mass or more, and more preferably such that the purity of the undiluted solution is 99.9% by mass or more. The upper limit is preferably 99.9999% by mass or less.

Examples of the purification method include passing the raw material through an ion exchange resin or a reverse osmosis membrane (RO membrane), reprecipitation, distillation of the raw material, and filtering.
The purification process may be a combination of the above purification methods. For example, the raw material may be subjected to a primary purification process in which the raw material is passed through an RO membrane, and then a secondary purification process in which the raw material is passed through a purification device made of a cation exchange resin, an anion exchange resin, or a mixed-bed ion exchange resin.
The purification process may be carried out multiple times.

The filter used for filtering is not particularly limited as long as it is one that has been conventionally used for filtering purposes. Examples include filters made of fluororesins such as polytetrafluoroethylene (PTFE) and tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA), polyamide resins such as nylon, polyarylsulfone (PAS), and polyolefin resins (including high density or ultra-high molecular weight) such as polyethylene and polypropylene (PP). Among these materials, materials selected from the group consisting of polyethylene, polypropylene (including high density polypropylene), fluororesins (including PTFE and PFA), and polyamide resins (including nylon) are preferred, and fluororesin filters are more preferred. Filtering the raw material using a filter made of these materials can effectively remove highly polar foreign matter that is likely to cause defects.

<Container>
The treatment liquid (including the diluted treatment liquid described below) can be filled into any container for storage, transport and use, so long as corrosiveness and other issues do not pose a problem.

The container is preferably one that is highly clean for semiconductor applications and that suppresses the elution of impurities from the inner wall of the container's storage section into each liquid. Examples of such containers include various containers that are commercially available as containers for semiconductor processing liquids, such as the "Clean Bottle" series manufactured by Aicello Chemical Co., Ltd. and the "Pure Bottle" manufactured by Kodama Resin Industry Co., Ltd., but are not limited thereto.
In addition, the containers exemplified in paragraphs [0121] to [0124] of WO 2022/004217 can also be used, the contents of which are incorporated herein by reference.

These containers are preferably cleaned inside before being filled with the treatment liquid. The liquid used for cleaning is preferably one that has a reduced amount of metal impurities. After production, the treatment liquid may be bottled in containers such as gallon bottles or coated bottles, and then transported and stored.

In order to prevent changes in the components of the treatment liquid during storage, the inside of the container may be replaced with an inert gas (nitrogen, argon, etc.) with a purity of 99.99995% by volume or higher. Gases with a low water content are particularly preferred. In addition, the treatment liquid may be stored and transported at room temperature, or the temperature may be controlled to a range of -20°C to 20°C to prevent deterioration.

<Clean room>
It is preferable that all of the manufacturing of the treatment liquid, the opening and cleaning of the container, the handling including filling of the treatment liquid, the treatment analysis, and the measurement are carried out in a clean room. The clean room preferably meets the 14644-1 clean room standard. It is preferable that the clean room meets any of ISO (International Organization for Standardization) Class 1, ISO Class 2, ISO Class 3, and ISO Class 4, more preferably ISO Class 1 or ISO Class 2, and even more preferably ISO Class 1.

[Dilution process]
The treatment liquid may be subjected to a dilution process in which the concentrated liquid is diluted with a diluent such as water, and then the diluted treatment liquid (diluted treatment liquid) may be used to treat the target object. In other words, the treatment liquid may be used after being diluted with a diluent containing water.
In addition, concentrated solutions and diluted processing solutions are also forms of the processing solution of the present invention so long as they satisfy the requirements of the present invention.

It is preferable to perform a purification treatment beforehand for the dilution liquid used in the dilution step. It is more preferable to perform a purification treatment on the diluted liquid obtained in the dilution step.
Examples of the purification treatment include the ion component reduction treatment using an ion exchange resin or an RO membrane, etc., and the removal of foreign matter using filtering, which are described above as purification treatments for the treatment liquid, and it is preferable to perform any one of these treatments.

The dilution rate of the treatment liquid in the dilution step may be appropriately adjusted depending on the type and content of each component, and the object to be treated. The ratio of the diluted treatment liquid to the treatment liquid before dilution (dilution ratio) is preferably 10 to 10,000 times, more preferably 10 to 1,000 times, and even more preferably 10 to 300 times, in terms of mass ratio or volume ratio (volume ratio at 23° C.).
In addition, in terms of superior removability of residues, the dilution liquid preferably contains water, and more preferably is water.

The change in pH before and after dilution (the difference between the pH of the treatment liquid before dilution and the pH of the diluted treatment liquid) is preferably 2.0 or less, more preferably 1.8 or less, and even more preferably 1.5 or less.
The pH of the treatment liquid before dilution and the pH of the diluted treatment liquid are preferably in the above-mentioned preferred embodiments.

The specific method of the dilution process for diluting the treatment liquid may be similar to that of the above-mentioned treatment liquid preparation process. The stirring device and stirring method used in the dilution process may also be the same as those known in the art as those mentioned in the above-mentioned treatment liquid preparation process.

[Use of processing liquid]
The treatment liquid of the present invention is preferably used for cleaning an object that has been subjected to a chemical mechanical polishing (CMP) treatment.
As described above, when the processing liquid is used, the processing liquid may be diluted before use.

<Target object>
The object to which the treatment liquid is applied may be, for example, an object containing a metal, such as a semiconductor substrate containing a metal.
When the semiconductor substrate contains a metal, the metal may be present on any of the front and back surfaces, side surfaces, and inside the grooves of the semiconductor substrate, for example. When the semiconductor substrate contains a metal, the metal may be present not only directly on the surface of the semiconductor substrate, but also on the semiconductor substrate via another layer.

Examples of the metal include at least one metal M selected from the group consisting of copper (Cu), cobalt (Co), ruthenium (Ru), aluminum (Al), tungsten (W), titanium (Ti), tantalum (Ta), chromium (Cr), hafnium (Hf), osmium (Os), platinum (Pt), nickel (Ni), manganese (Mn), iron (Fe), zirconium (Zr), molybdenum (Mo), palladium (Pd), lanthanum (La), and iridium (Ir), with Cu, Co, or Ru being preferred, and Cu or Co being more preferred. In other words, the object is preferably an object containing at least one metal selected from the group consisting of Cu and Co.
The treatment liquid of the present invention can be suitably used for cleaning the copper surface of an object when the object has a copper surface that has been subjected to chemical mechanical polishing.

The metal may be any substance that contains a metal (metal atom), and examples include the metal M alone and alloys that contain metal M.

The object to be treated with the treatment liquid may include, for example, a semiconductor substrate, a metal wiring film, a barrier metal, and an insulating film.

Examples of wafers constituting semiconductor substrates include wafers made of silicon-based materials such as silicon (Si) wafers, silicon carbide (SiC) wafers, resin-based wafers containing silicon (glass epoxy wafers), gallium nitride (GaN), gallium phosphide (GaP) wafers, gallium arsenide (GaAs) wafers, and indium phosphide (InP) wafers.
Examples of silicon wafers include n-type silicon wafers doped with pentavalent atoms (e.g., phosphorus (P), arsenic (As), antimony (Sb), etc.) and p-type silicon wafers doped with trivalent atoms (e.g., boron (B), gallium (Ga), etc.). Examples of silicon in silicon wafers include amorphous silicon, single crystal silicon, polycrystalline silicon, and polysilicon.
Among these, wafers made of silicon-based materials such as silicon wafers, silicon carbide wafers, and resin-based wafers containing silicon (glass epoxy wafers) are preferred.

Examples of the insulating film include silicon oxide films (e.g., silicon dioxide (SiO ₂ ) film and tetraethyl orthosilicate (Si(OC ₂ H ₅ ) ₄ ) film (TEOS film), etc.), silicon nitride films (e.g., silicon nitride (Si ₃ N ₄ ) and silicon carbide nitride (SiNC), etc.), and low dielectric constant (Low-k) films (e.g., carbon-doped silicon oxide (SiOC) film and silicon carbide (SiC) film, etc.), with low dielectric constant (Low-k) films being preferred.

As the metal wiring film, a copper-containing film, a cobalt-containing film, and a ruthenium-containing film are preferable.
Examples of copper-containing films include wiring films made only of metallic copper (copper wiring films) and wiring films made of an alloy of metallic copper and another metal (copper alloy wiring films).
Examples of copper alloy wiring films include wiring films made of an alloy of copper and one or more metals selected from Al, Ti, Cr, Mn, Ta, and W. More specifically, examples of the wiring film include a copper-aluminum alloy wiring film (CuAl alloy wiring film), a copper-titanium alloy wiring film (CuTi alloy wiring film), a copper-chromium alloy wiring film (CuCr alloy wiring film), a copper-manganese alloy wiring film (CuMn alloy wiring film), a copper-tantalum alloy wiring film (CuTa alloy wiring film), and a copper-tungsten alloy wiring film (CuW alloy wiring film).

Examples of the cobalt-containing film include a metal film made only of metallic cobalt (cobalt metal film) and a metal film made of an alloy made of metallic cobalt and another metal (cobalt alloy metal film).
Examples of the cobalt alloy metal film include metal films made of an alloy of cobalt and one or more metals selected from Ti, Cr, Fe, Ni, Mo, Pd, Ta, and W. More specifically, examples of the cobalt alloy metal film include a cobalt-titanium alloy metal film (CoTi alloy metal film), a cobalt-chromium alloy metal film (CoCr alloy metal film), a cobalt-iron alloy metal film (CoFe alloy metal film), a cobalt-nickel alloy metal film (CoNi alloy metal film), a cobalt-molybdenum alloy metal film (CoMo alloy metal film), a cobalt-palladium alloy metal film (CoPd alloy metal film), a cobalt-tantalum alloy metal film (CoTa alloy metal film), and a cobalt-tungsten alloy metal film (CoW alloy metal film).

Examples of ruthenium-containing films include metal films consisting only of metallic ruthenium (ruthenium metal film) and metal films made of alloys consisting of metallic ruthenium and other metals (ruthenium alloy metal film).

There are no particular limitations on the method for forming the insulating film, copper-containing film, cobalt-containing film, and ruthenium-containing film on the wafer constituting the semiconductor substrate, so long as it is a method commonly used in this field.
An example of a method for forming an insulating film is a method in which a wafer constituting a semiconductor substrate is heat-treated in the presence of oxygen gas to form a silicon oxide film, and then silane and ammonia gases are introduced to form a silicon nitride film by a chemical vapor deposition (CVD) method.
Examples of methods for forming the copper-containing film, the cobalt-containing film, and the ruthenium-containing film include a method in which a circuit is formed on a wafer having the insulating film by a known method such as a resist, and then a copper-containing film, a cobalt-containing film, and a ruthenium-containing film are formed by a method such as plating and CVD.

<CMP Treatment>
The object is an object that has been subjected to a CMP process (preferably, an object having a metal that has been subjected to a CMP process).
CMP processing is a process in which the surface of a semiconductor substrate having, for example, a metal wiring film, a barrier metal, and an insulating film is planarized by a combined chemical and mechanical polishing action using a polishing slurry containing polishing particles (abrasive grains).

<Objects that have been subjected to pad cleaning treatment>
The surface of the object may be subjected to a pad cleaning process after the CMP process.
The pad cleaning process is a process for reducing residues present on the surface of a treated area using a pad. Specifically, the surface of a treated object that has been subjected to CMP is brought into contact with a pad, and the object and the pad are slid relative to each other while a pad cleaning composition is supplied to the contact portion. As a result, the residues on the surface of the object are removed by the frictional force of the pad and the chemical action of the pad cleaning composition.

The pad is not particularly limited and can be selected appropriately depending on the type of object, the type of residue to be removed, and the device to be used. The pad may be an abrasive pad used in CMP processing, or a buff pad such as a foamed polyurethane buff pad, a nonwoven fabric, a suede buff pad, or a sponge. Note that pad cleaning processing using a pad includes processing called buff cleaning or buff polishing.

As the pad cleaning composition, a known cleaning composition can be used depending on the type of object and the type and amount of residue to be removed. Examples of components contained in the pad cleaning composition include ammonium fluoride (NH ₄ F), 1-hydroxyethylidene-1,1'-diphosphonic acid (HEDPO), water-soluble polymers such as polyvinyl alcohol, a dispersion medium such as water, and an acid such as nitric acid. In addition, the pad cleaning composition does not contain abrasive particles.

The equipment and conditions used in the pad cleaning process can be appropriately selected from known equipment and conditions depending on the type of object and the type and amount of residue to be removed. For example, the processing method described in paragraphs [0085] to [0088] of WO 2017/169539 can be used, and the contents of these methods are incorporated herein.

As one embodiment of the pad cleaning treatment, it is also preferable to perform pad cleaning treatment on an object using the treatment liquid of the present invention as a pad cleaning composition.
The treatment liquid used in the pad cleaning process may be a diluted treatment liquid.

The pad cleaning process may be performed only once, or may be performed two or more times. For example, after the CMP process, a pad cleaning process using a polishing pad and a pad cleaning process using a buff pad may be performed.

[Method of processing object]
The method for treating an object of the present invention is not particularly limited as long as it is a treatment method including a step of contacting the object with the treatment liquid of the present invention (contact step).
The above-mentioned processing method can be used to clean, for example, a semiconductor substrate that has been subjected to a CMP process. The above-mentioned semiconductor substrate cleaning method preferably includes a step of applying the diluted processing solution obtained in the above-mentioned dilution step to a semiconductor substrate that has been subjected to a CMP process to clean the substrate.

The method for contacting the object with the treatment liquid is not particularly limited, and examples thereof include a method of immersing the object in the treatment liquid contained in a tank, a method of spraying the treatment liquid on the object, a method of pouring the treatment liquid on the object, and combinations thereof. The above method may be appropriately selected depending on the purpose.
The above method may be appropriately adopted from the methods usually used in this field. For example, it may be a scrub cleaning method in which a cleaning member such as a brush is brought into physical contact with the surface of the object while supplying the processing liquid to remove residues, or a spin (drop) method in which the processing liquid is dropped onto the object while rotating the object. In the immersion method, it is preferable to perform ultrasonic treatment on the object immersed in the processing liquid, since impurities remaining on the surface of the object can be further reduced.

The contact between the object and the treatment liquid in the contact step may be carried out only once, or may be carried out two or more times. When the object is contacted two or more times, the same method may be repeated, or different methods may be combined.

The contact step may be carried out by either a single wafer method or a batch method.
The single-wafer method generally refers to a method in which objects are processed one by one, while the batch method generally refers to a method in which a plurality of objects are processed simultaneously.

There are no particular limitations on the temperature of the processing liquid, so long as it is a temperature that is normally used in this field. Generally, processing is performed at room temperature (approximately 25°C), but the temperature can be selected as desired to improve residue removal and minimize damage to components. For example, the temperature of the processing liquid is preferably 10 to 60°C, and more preferably 15 to 50°C.

The contact time between the object and the treatment liquid can be changed as appropriate depending on the type and amount of components contained in the treatment liquid. In practice, 10 seconds to 2 minutes is preferable, 20 seconds to 1 minute and 30 seconds is more preferable, and 30 seconds to 1 minute is even more preferable.

The amount (supply rate) of the treatment liquid supplied in the contact step is preferably 50 to 5,000 mL/min, and more preferably 500 to 2,000 mL/min.

In the contact step, a mechanical stirring method may be used to further enhance the residue removal properties of the treatment solution.
Examples of the mechanical stirring method include a method of circulating the treatment liquid above the semiconductor substrate, a method of passing or spraying the treatment liquid above the semiconductor substrate, and a method of stirring the treatment liquid by ultrasonic waves or megasonics.

In addition, after the contacting step, a step of contacting the object with a rinse liquid (hereinafter, also referred to as a "rinsing step") may be performed. By performing the rinsing step, the object obtained in the contacting step can be washed with the rinse liquid, and residues can be efficiently removed.
The rinsing step is preferably performed consecutively after the cleaning step of the object, and is a step of rinsing the object with a rinsing liquid. The rinsing step may be performed using the mechanical stirring method described above.

Rinse solvents include, for example, water (preferably deionized (DI) water), methanol, ethanol, isopropyl alcohol, N-methylpyrrolidinone, gamma-butyrolactone, dimethylsulfoxide, ethyl lactate, and propylene glycol monomethyl ether acetate. In addition, an aqueous rinse solution having a pH greater than 8.0 (such as diluted aqueous ammonium hydroxide) may be used.

As a method for contacting the object with the rinse liquid, the above-mentioned method for contacting the object with the treatment liquid can be similarly applied.
The contact time between the object and the rinse liquid can be appropriately changed depending on the type and content of each component contained in the treatment liquid, and the object and purpose of use of the treatment liquid. In practice, the contact time is preferably 10 to 120 seconds, more preferably 20 to 90 seconds, and even more preferably 30 to 60 seconds.

After the rinsing step, a drying step may be performed to dry the object.
Examples of the drying method include a spin drying method, a method of passing a dry gas over a semiconductor substrate, a method of heating the substrate by a heating means such as a hot plate or an infrared lamp, a Marangoni drying method, a Rotagoni drying method, an IPA (isopropyl alcohol) drying method, and any combination of these methods.

[Method of manufacturing semiconductor device]
The above-described method for processing an object can be suitably applied to a method for manufacturing a semiconductor device.
The cleaning method may be carried out in combination with other processes carried out on the substrate, before or after the other processes, or may be incorporated into other processes while carrying out the cleaning method, or may be incorporated into other processes.
Other processes include, for example, processes for forming structures such as metal wiring, gate structures, source structures, drain structures, insulating films, ferromagnetic layers, and non-magnetic layers (e.g., layer formation, etching, chemical mechanical polishing, and modification), resist formation processes, exposure processes, and removal processes, heat treatment processes, cleaning processes, and inspection processes.

The above processing method may be performed at any stage of the back-end process (BEOL: Back end of the line), middle process (MOL: Middle of the line), or front-end process (FEOL: Front end of the line), and is preferably performed in the front-end process or middle process.

The present invention will be described in further detail below with reference to examples.
The materials, amounts, ratios, processing contents, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the following examples.

In the following examples, the pH of the treatment solution was measured at 25° C. using a pH meter (manufactured by Horiba, Ltd., model "F-74") in accordance with JIS Z8802-1984.
In addition, in producing the treatment solutions of the Examples and Comparative Examples, handling of containers, preparation, filling, storage and analysis of the treatment solutions were all carried out in a clean room of a level satisfying ISO class 2 or lower.

[Raw materials for processing liquid]
The following compounds were used to prepare the treatment solution. Note that all of the components used in the examples were classified as semiconductor grade or equivalent high purity grade.

[Hydroxyl-containing carboxylic acid]
・Citric acid ・Malic acid ・Tartaric acid

[Phosphonic acid compounds]
・H.E.D.P.
・NTMP
EDTMP

[Anionic polymer]
PA: Polyacrylic acid (Mw (weight average molecular weight): 6000)
PB: Polystyrene sulfonic acid (Mw: 75,000)
PC: Polyvinyl sulfonic acid (Mw: 8000)
PD: Poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (Mw: 6000)
PE: 2-acrylamide-2-methyl-1-propanesulfonic acid-acrylic acid copolymer (Mw: 8500)
PF: polycarboxylic acid polyalkylene glycol grafted compound (Mw: 3000, AQUALIC PM-303B, manufactured by Nippon Shokubai Co., Ltd.)
PG: Polyvinylphosphonic acid (Mw: 24000)

[Anionic Surfactants]
SA: Dodecylbenzenesulfonic acid SB: Naphthalenesulfonic acid formalin condensate (Mw: 2000)
SC: C12-C14 alkyl diphenyl ether disulfonic acid SD: lauryl sulfonic acid SE: trideceth-4 carboxylic acid

[Other ingredients]
Oxalic acid

[pH adjuster, ultrapure water]
As a pH adjuster, either potassium hydroxide (KOH) or sulfuric acid (H ₂ SO ₄ ) was used as necessary.
The contents of potassium hydroxide and sulfuric acid were 2% by mass or less based on the total mass of each treatment liquid.
In addition, ultrapure water (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used in preparing the treatment liquid.

[Preparation of Processing Solution]
Next, the manufacturing method of each of the treatment liquids of the examples and comparative examples will be described using Example 1 as an example.
Citric acid, HEDP, PA, and SA were added to ultrapure water so that the content of each component was the blending ratio shown in each table, and then a pH adjuster was added so that the pH of the mixed liquid was 1.4. The content of ultrapure water is the remainder of the treatment liquid after subtracting the content of each component used in the preparation of the treatment liquid other than ultrapure water.
The resulting mixture was thoroughly stirred to prepare the treatment liquid of Example 1.
According to the manufacturing method of the treatment liquid of Example 1, each treatment liquid of the Examples and Comparative Examples having the composition shown in the following table was prepared.

[evaluation]
Next, the following evaluations were carried out using each of the treatment solutions of the Examples and Comparative Examples produced by the above-mentioned methods.

[Evaluation of organic residue removal on wafers having copper (Cu) films]
The removability of organic residues (number of defects) when a chemically mechanically polished semiconductor substrate was cleaned was evaluated.
Using a FREX300S-II (polishing device, manufactured by Ebara Corporation), a wafer (diameter 12 inches) having a Cu film on its surface was polished using polishing liquid 1 as the polishing liquid under the conditions of an in-plane average polishing pressure of 105 hPa, a polishing liquid supply rate of 200 mL/min, and a polishing time of 30 seconds. Next, using polishing liquid 2 as the polishing liquid, the wafer that had been subjected to the above polishing treatment was further polished under the conditions of an in-plane average polishing pressure of 70 hPa, a polishing liquid supply rate of 200 mL/min, and a polishing time of 60 seconds.
The resulting CMP-treated wafer was scrubbed for 1 minute with a 100-fold diluted sample (diluted with pure water) of the treatment liquid adjusted to room temperature (23° C.), and then dried.
The compositions of the polishing solutions 1 and 2 are as follows:
Polishing liquid 1 (pH 7.0)
Colloidal silica (PL3, manufactured by Fuso Chemical Co., Ltd.) 0.1% by mass
Glycine 1.0% by mass
0.2% by mass of 3-amino-1,2,4-triazole
Benzotriazole (BTA) 30 ppm by mass
Hydrogen peroxide 1.0% by mass
・pH adjuster (ammonia and nitric acid)
・Water remainder Polishing liquid 2 (pH 10.5)
Colloidal silica (PL3, manufactured by Fuso Chemical Co., Ltd.) 6.0% by mass
Citric acid 1.0% by mass
Alkyl alkoxylate surfactant 100 ppm by mass
・BTA 0.2% by mass
Hydrogen peroxide 1.0% by mass
・pH adjuster (potassium hydroxide and nitric acid)
・Water remainder

Next, using a defect detection device (Surfscan SP5 manufactured by KLA Corporation), the number of defects (total number of defects) having a length of 0.036 μm or more was counted on the polished surface of the obtained wafer.
Thereafter, images of 100 random defects were observed using a SemVision G5 (manufactured by Applied Materials), and the number of organic residues in the 100 defects was counted to estimate the proportion of defects originating from organic matter.
The number of organic residues was calculated by multiplying the "total number of defects" by the "ratio of organic matter", and was evaluated based on the following evaluation criteria: A rating is most preferable, and a rating of C or higher is practically preferable.

(Evaluation Criteria)
A: The number of organic residues per wafer is less than 20. B: The number of organic residues per wafer is 20 or more and less than 50. C: The number of organic residues per wafer is 50 or more and less than 100. D: The number of organic residues per wafer is 100 or more.

[Evaluation of organic residue removal on wafers having tungsten (W) films]
The removability of organic residue on a wafer having a W film was evaluated in the same manner as in the evaluation method and evaluation criteria described above in [Evaluation of organic residue removability on a wafer having a copper (Cu) film], except that a wafer (diameter 12 inches) having a Cu film on its surface was changed to a wafer (diameter 12 inches) having a W film on its surface and the pH of the polishing solutions 1 and 2 was changed to 4.0.

[Evaluation of corrosion inhibition performance]
Copper coupon wafers measuring 2×2 cm were prepared and used to evaluate the corrosion inhibition performance of the treatment liquid against Cu.
The wafers were immersed for 30 minutes at room temperature (25° C.) in each of the treatment liquids and in each of the treatment liquids that had been left stationary for 6 months at room temperature (25° C.).
The thickness of the wafer was then measured, and the etching rate (Å/min) was calculated from the difference in thickness before and after the immersion treatment. The lower the etching rate, the better the corrosion inhibition performance, and a rate of 1.0 Å/min or less is preferable for practical use.

[result]
Tables 1 and 2 show the composition of each treatment liquid used in the examples and comparative examples, and the evaluation results of each treatment liquid.
Table 1 (continued) is a continuation of Table 1. The same applies to Table 2. For example, in Example 1, a treatment solution having a composition of 20 mass % citric acid, 0.5 mass % HEDP, 0.1 mass % PA, and 0.07 mass % SA, and having a pH of 1.4 and 2.5 before and after dilution, respectively, was used for evaluation, and the results show that the organic residue removability was "A" and the copper etching rate was 0.3 Å/min immediately after preparation and after storage at room temperature for 6 months.
In the table, the values in the "Content (wt %)" column indicate the content (mass %) of each component relative to the total mass of the treatment liquid.
The numerical values in the "pH" column indicate the pH of each treatment liquid prepared in the above-mentioned "Preparation of treatment liquid", and the numerical values in the "pH after dilution" column indicate the pH of the diluted sample of each treatment liquid used in the above-mentioned "Evaluation of organic residue removability".
The numerical value in the "Ratio" column indicates the content ratio (mass ratio) of each component. The numerical value in the "Phosphonic acid/Polymer" column indicates the mass ratio of the content of the phosphonic acid compound to the content of the anionic polymer. The numerical value in the "Carboxylic acid/Polymer" column indicates the mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer. The numerical value in the "Polymer/Total Solids" column indicates the mass ratio of the content of the anionic polymer to the total solids of the treatment liquid.

From the results in the table, it was confirmed that the treatment liquid of the present invention, when applied to an object having a copper surface that has been subjected to chemical mechanical polishing, causes less copper corrosion and is excellent in removing organic residues from the copper surface. Furthermore, it was confirmed that the treatment liquid of the present invention, when applied to an object having a tungsten surface that has been subjected to chemical mechanical polishing, is also excellent in removing organic residues from the tungsten surface.
Furthermore, by comparing Examples 1 to 7, it was confirmed that when the mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer is 10 or more, the removability of organic residues is superior, and when it is 100 or more, the removability of organic residues is even superior.
From a comparison of Examples 1 to 4, it was confirmed that when the mass ratio of the anionic polymer content to the total solid content of the treatment liquid is 0.1 or less, the organic residue removability is superior, and when the mass ratio of the anionic polymer content to the total solid content of the treatment liquid is 0.0001 or more, the organic residue removability is superior and copper corrosion is reduced.
Comparison of Examples 8 to 16 and the like confirmed that when the anionic polymer did not have a repeating unit derived from an acrylamide-based monomer, even when a copper-containing object was treated with a treatment liquid that had been stored at room temperature for six months, there was little change in the properties of the treatment liquid over time and little corrosion of copper.

Claims (16)

an anionic polymer;
A phosphonic acid compound,
and a hydroxyl-containing carboxylic acid,
a mass ratio of the content of the phosphonic acid compound to the content of the anionic polymer is 0.1 to 1000;
A processing solution used in semiconductor manufacturing processes, having a pH of 0.1 to 7.0. The treatment solution according to claim 1, wherein the hydroxyl-containing carboxylic acid is selected from the group consisting of citric acid, malic acid, tartaric acid, glycolic acid, lactic acid, tartronic acid, glyceric acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, γ-hydroxybutyric acid, citramalic acid, isocitric acid, leucic acid, mevalonic acid, pantoic acid, ricinoleic acid, ricineraidic acid, cerebronic acid, quinic acid, shikimic acid, salicylic acid, creosote acid, vanillic acid, syringic acid, pyrocatechuic acid, resorcylic acid, protocatechuic acid, gentisic acid, orselliic acid, gallic acid, mandelic acid, benzilic acid, atrolactic acid, mellitic acid, phloretic acid, coumaric acid, umbellic acid, caffeic acid, ferulic acid, and sinapic acid. The treatment solution according to claim 1, wherein the phosphonic acid compound is selected from the group consisting of etidronic acid, nitrilotris(methylene phosphonic acid), ethylenediaminetetramethylene phosphonic acid, and 2-phosphonobutane-1,2,4-tricarboxylic acid. The treatment solution according to claim 1, wherein the anionic polymer is selected from the group consisting of polyacrylic acid, polystyrene sulfonic acid, polyvinyl sulfonic acid, poly(2-acrylamido-2-methyl-1-propanesulfonic acid), 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, polyvinyl phosphonic acid, poly(N-vinyl acetamide), and styrene sulfonic acid-acrylic acid-vinyl phosphonic acid copolymer. The treatment liquid according to claim 1, wherein the anionic polymer does not have repeating units derived from an acrylamide monomer. The treatment liquid according to claim 1, wherein the mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer is 10 or more. The treatment liquid according to claim 1, wherein the mass ratio of the content of the hydroxyl group-containing carboxylic acid to the content of the anionic polymer is 100 or more. The treatment liquid according to claim 1, wherein the mass ratio of the content of the anionic polymer to the total solid content of the treatment liquid is 0.0001 to 0.1. The treatment liquid according to claim 1, further comprising an anionic surfactant selected from the group consisting of sulfonic acid surfactants, carboxylic acid surfactants, and phosphate ester surfactants. The treatment liquid according to claim 9, wherein the anionic surfactant is a sulfonic acid surfactant having an alkyl chain with 6 or more carbon atoms. The treatment solution according to claim 1, which is used to clean an object that has been subjected to chemical mechanical polishing. The treatment solution according to claim 11, wherein the object has a copper surface that has been subjected to a chemical mechanical polishing process, and the treatment solution is used to clean the copper surface. The treatment solution according to claim 1, which is diluted with a diluent containing water. The treatment solution according to claim 1, which does not contain a quaternary ammonium salt. A method for treating an object, comprising a step of contacting the object that has been subjected to chemical mechanical polishing with the treatment liquid according to any one of claims 1 to 14. A method for manufacturing a semiconductor device, comprising the method for processing an object according to claim 15.