Treatment liquid and method for treating object to be treated

Abstract

The present invention addresses the problem of providing: a processing liquid which is used for a semiconductor device and has excellent performance of suppressing surface roughness of a metal film containing cobalt; and a method for processing an object to be processed using the processing liquid. The processing liquid of the present invention is a processing liquid for a semiconductor device, the processing liquid comprising: water; a first component which is an alicyclic heterocyclic compound containing a nitrogen atom as a ring-forming atom; and a second component that is a compound different from the first component and that is an alicyclic heterocyclic compound having a hydroxyl group.

Description

Technical Field

[0001] This invention relates to a treatment liquid and a method for treating a substance. Background Technology

[0002] As semiconductor devices become increasingly miniaturized, the demand for high-efficiency and high-precision etching and cleaning processes using processing solutions in semiconductor device manufacturing is constantly increasing.

[0003] For example, Patent Document 1 discloses a cleaning composition comprising an oxidizing agent, two chelating agents, a metal corrosion inhibitor, an organic solvent, water, and a desired pH adjuster, as well as a technique including a method for contacting a semiconductor substrate with the cleaning composition.

[0004] Previous technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Publication No. 2017-504190 Summary of the Invention

[0007] The technical problem to be solved by the invention

[0008] Based on their research on the processing liquid described in Patent Document 1, the inventors have determined that when the processing liquid is applied to a workpiece containing a cobalt-containing metal film that serves as a wiring material or plug material, the surface of the metal film becomes rough, which may result in minor unevenness. There is room for further improvement in this regard.

[0009] Therefore, in view of the above facts, the objective of the present invention is to provide a processing liquid that is used for semiconductor devices and has excellent performance in suppressing the surface roughness of metal films containing cobalt.

[0010] Furthermore, the objective of this invention is to provide a method for treating a workpiece using the aforementioned treatment liquid.

[0011] means for solving technical problems

[0012] As a result of in-depth research conducted by the inventors to solve the above-mentioned problems, they discovered that the above-mentioned problems could be solved by including two specific components in the treatment liquid, thus completing the present invention.

[0013] That is, it was found that the above problems can be solved through the following structure.

[0014] [1] A processing liquid for use in semiconductor devices, the processing liquid comprising: water; a first component, which is an alicyclic heterocyclic compound containing nitrogen atoms as cyclic atoms; and a second component, which is a compound different from the first component and is an alicyclic heterocyclic compound having hydroxyl groups.

[0015] [2] According to the treatment solution described in [1], wherein,

[0016] The first component mentioned above has two or more nitrogen atoms as cyclic atoms.

[0017] [3] The treatment solution according to [1] or [2], wherein,

[0018] The first component mentioned above contains at least one selected from 1,8-diazabicyclo[5.4.0]undec-7-ene and 1,5-diazabicyclo[4.3.0]non-5-ene.

[0019] [4] The treatment solution according to any one of [1] to [3], wherein,

[0020] The second component mentioned above contains nitrogen or oxygen atoms as cyclic atoms.

[0021] [5] The treatment solution according to any one of [1] to [4], wherein,

[0022] The second component mentioned above is either the compound represented by formula (1) or the compound represented by formula (2) described later.

[0023] [6] The treatment solution according to any one of [1] to [5], wherein,

[0024] The water content is 70% or more by mass relative to the total mass of the treated liquid.

[0025] [7] The treatment liquid according to any one of [1] to [6] further comprises a chelating agent having a carboxylic acid group or a chelating agent having a phosphonic acid group.

[0026] [8] The treatment liquid according to any one of [1] to [7] further comprises an organic solvent.

[0027] [9] The treatment solution according to [8], wherein,

[0028] The aforementioned organic solvents include at least one selected from glycol solvents, glycol ether solvents, amide solvents, alcohol solvents, and sulfoxide solvents.

[0029]

[10] The treatment solution according to any one of [1] to [9] further comprises a preservative.

[0030]

[11] The treatment solution according to

[10] , wherein,

[0031] The preservatives described above include at least one compound selected from the compounds represented by formula (A), formula (B), formula (C), and substituted or unsubstituted tetrazolium.

[0032]

[12] The treatment solution according to any one of [1] to

[11] further comprises at least one hydroxylamine compound selected from hydroxylamine, hydroxylamine derivatives and their salts.

[0033]

[13] The treatment solution according to any one of [1] to

[12] further comprises an inorganic acid.

[0034]

[14] A method for processing a workpiece comprising a step of contacting the workpiece having a cobalt-containing layer with a processing liquid as described in any one of [1] to

[13] .

[0035] Invention Effects

[0036] According to the present invention, a processing liquid can be provided that is used for semiconductor devices and has excellent performance in suppressing the surface roughness of metal films containing cobalt.

[0037] Furthermore, the present invention can provide a method for treating a workpiece using the above-described treatment liquid. Detailed Implementation

[0038] The present invention will now be described in detail.

[0039] The following description of the constituent elements is sometimes based on representative embodiments of the present invention, but the present invention is not limited to these embodiments.

[0040] In addition, in this specification, the numerical range indicated by “~” refers to the range included by taking the values ​​recorded before and after “~” as the lower limit and upper limit values.

[0041] In this instruction manual, "preparation" means, in addition to the synthesis and formulation of specific materials, the acquisition of specified materials through purchase or other means.

[0042] In this specification, if there are two or more components, unless otherwise specified, the “content” of the component refers to the total content of these two or more components.

[0043] Unless otherwise specified, the term "compound" in this specification refers to structural isomers, optical isomers, and isotopes containing such compounds. Furthermore, structural isomers, optical isomers, and isotopes may comprise one or more individual compounds.

[0044] In this manual, "ppm" refers to "parts per million (10 -6 "ppb" refers to "parts-per-billion (10 -9 "ppt" refers to "parts-per-trillion (10)". -12 )".

[0045] In this specification, "radiation" refers to, for example, the bright-line spectrum of a mercury lamp, far-ultraviolet light (EUV light) represented by an excimer laser, X-rays, or electron beams. Furthermore, in this specification, "light" refers to photochemical rays or radiation. Unless otherwise stated, "exposure" in this specification includes not only exposure based on far-ultraviolet light, X-rays, or EUV light represented by a mercury lamp or excimer laser, but also descriptions based on particle beams such as electron beams or ion beams.

[0046] [Processing fluid] (as described in claim 1)

[0047] The processing solution of the present invention (hereinafter also referred to as "this processing solution") is a processing solution for semiconductor devices, the processing solution comprising: water; a first component, which is an alicyclic heterocyclic compound containing nitrogen atoms as cyclic atoms; and a second component, which is different from the first component and is an alicyclic heterocyclic compound having hydroxyl groups.

[0048] The characteristic of this treatment solution is that it contains alicyclic heterocyclic compounds having defined structures, namely the first component and the second component described above. The treatment solution used in the treatment of cobalt-containing metal films (hereinafter also referred to as "Co-containing films"), by containing the first and second components, can achieve the effect of suppressing the generation of surface roughness in the treated Co-containing films (hereinafter also referred to as "effects of the present invention").

[0049] The following is a detailed description of each component contained in the treatment solution.

[0050] 〔water〕

[0051] This treatment solution contains water.

[0052] There are no particular restrictions on the type of water used; for example, distilled water, ion-exchanged water, and pure water can be cited, with ultrapure water preferred for use in the manufacture of semiconductor devices.

[0053] As for the water, water with reduced inorganic anions and metal ions is preferred; water with reduced ion concentrations of metal atoms selected from Fe, Co, Na, K, Ca, Cu, Mg, Mn, Li, Al, Cr, Ni, and Zn is more preferred; and water adjusted to a ppt level or lower (in one embodiment, the metal content is less than 0.001 ppt by mass) is even more preferred when used to prepare the treatment solution. As for the adjustment method, purification using a filtration membrane or ion exchange membrane or purification based on distillation is preferred. Examples of adjustment methods include those described in paragraphs

[0074] to

[0084] of Japanese Patent Application Publication No. 2011-110515 and those described in Japanese Patent Application Publication No. 2007-254168.

[0054] Preferably, the water contained in this treatment solution is water obtained through the above-described treatment. Furthermore, from the viewpoint of clearly obtaining the effects of the present invention, it is more preferable that the water is used not only for the treatment solution but also for cleaning the containing container. Furthermore, it is preferable that the water is also used in the manufacturing process of the treatment solution, the determination of the composition of the treatment solution, and the determination of the evaluation of the treatment solution.

[0055] The water content in the treatment solution is not particularly limited, but is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 75% by mass or more, and even more preferably 85% by mass or more, relative to the total mass of the treatment solution.

[0056] The upper limit of the water content relative to the total mass of the treatment liquid is, for example, 99.9% by mass or less, preferably 99.0% by mass or less.

[0057] The water content in the treatment solution was determined using well-known methods such as the Karl Fischer method.

[0058] [1st ingredient]

[0059] This treatment solution contains an alicyclic heterocyclic compound, namely component 1, which includes nitrogen atoms as cyclic atoms.

[0060] In this specification, "alicyclic heterocyclic compound" refers to a compound that has an alicyclic heterocycle (a non-aromatic heterocycle) and does not have an aromatic ring.

[0061] The first component is characterized by having an alicyclic heterocycle containing at least one nitrogen atom as a cyclizing atom.

[0062] The first component can be ionized in the treatment solution. The first component in the treatment solution can be, for example, an anion with added protons or an anion that has lost protons.

[0063] The alicyclic heterocycle of the first component can be a monocyclic ring or a condensed ring. When the alicyclic heterocycle is a condensed ring, at least one of the monocyclic rings constituting the condensed ring comprises at least one nitrogen atom as a cyclizing atom. In this case, at least one of the monocyclic rings constituting the condensed ring can be an alicyclic hydrocarbon. Furthermore, the alicyclic heterocycle can have unsaturated bonds or can consist only of saturated bonds. Additionally, the alicyclic heterocycle can have substituents.

[0064] The first component may have only one alicyclic heterocycle or two or more alicyclic heterocycles. When the first component has two or more alicyclic heterocycles, at least one alicyclic heterocycle serves as a cyclizing atom and contains at least one nitrogen atom. Preferably, the first component has only one alicyclic heterocycle that is a monocyclic or condensed ring, and more preferably, only one alicyclic heterocycle that is a condensed ring.

[0065] The alicyclic heterocycle can contain heteroatoms other than nitrogen atoms as cyclizing atoms. Examples of heteroatoms other than nitrogen atoms include oxygen atoms and sulfur atoms. Preferably, the alicyclic heterocycle of the first component contains only carbon atoms and nitrogen atoms as cyclizing atoms.

[0066] The number of heteroatoms (more preferably nitrogen atoms) included as cyclic atoms in the alicyclic heterocycle can be 1 or more, but is preferably more than 2, more preferably 2 to 4, and even more preferably 2 or 3.

[0067] There is no particular limitation on the number of ring elements in the monocyclic rings constituting the alicyclic heterocycle (in the case of a condensed ring, each monocyclic ring constituting the alicyclic heterocycle), for example, 5 to 8, preferably 5 to 7.

[0068] Examples of nitrogen-containing monocyclic rings that constitute the alicyclic heterocycles of the first component include, for example, pyrrolidine, piperidine, piperazine, hexahydropyrimidine, hexahydropyridazine, 1,2,3,6-tetrahydropyrazine, 1,4,5,6-tetrahydropyrimidine, aziridine, and aziridine.

[0069] Alicyclic heterocycles that contain at least one condensed ring of an alicyclic hydrocarbon include, for example, cyclopentane, cyclohexane and cycloheptane.

[0070] The alicyclic heterocycle of the first component is preferably a condensed ring consisting of two or three monocyclic rings as illustrated above, more preferably a condensed ring consisting of two monocyclic rings as illustrated above, and even more preferably a condensed ring consisting of monocyclic rings containing nitrogen atoms as two of the cyclic atoms illustrated above.

[0071] The alicyclic heterocycle of the first component may have substituents. Examples of substituents include aliphatic hydrocarbon groups, amino groups, oxo groups, and ketone groups having 1 to 5 carbon atoms. On the other hand, it is preferable that the first component does not have a hydroxyl group as a substituent for the alicyclic heterocycle.

[0072] There is no particular limitation on the number of substituents when alicyclic heterocycles have substituents, but one or two are preferred, and one is more preferred.

[0073] Preferably, the alicyclic heterocycle of the first component is without substituents or has alkyl groups having 1 to 5 carbon atoms as substituents, and more preferably, it is without substituents.

[0074] Examples of first components include, for instance, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.4.0]dec-5-ene, 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 1,4-diazabicyclo[2.2.2]octane, octahydro-2H-pyrimidino[1,2-a]pyrimidine, 2,5,6,7-tetrahydro-3H-pyrrolo[1.2-a]imidazolium, 1,8-diazabicyclo[5.4.0]undecane, 1,5-diazabicyclo[4.4.0]decane, 1,3-diazabicyclo[3.2.2]nonane, and hexahydro-1H-1,4-diazazoline.

[0075] Among them, DBU or DBN is preferred, with DBU being more preferred.

[0076] The first ingredient can be used alone or in combination with two or more ingredients.

[0077] There is no particular limitation on the content of the first component, but it is preferably 0.01 to 10% by mass relative to the total mass of the treatment liquid, and more preferably 0.1 to 5% by mass.

[0078] [Second ingredient]

[0079] This treatment solution contains a second component, which is a compound different from the first component and is an alicyclic heterocyclic compound having hydroxyl groups.

[0080] The second component can ionize in the treatment solution. In the treatment solution, the second component can be, for example, an anion with added protons or an anion that has lost protons.

[0081] The alicyclic heterocycle of the second component can be a monocyclic ring or a condensed ring. When the alicyclic heterocycle is a condensed ring, at least one of the monocyclic rings constituting the condensed ring is a cyclic atom and contains at least one heteroatom. In this case, at least one of the monocyclic rings constituting the condensed ring can be an alicyclic hydrocarbon. Furthermore, the alicyclic heterocycle can have unsaturated bonds or can consist only of saturated bonds.

[0082] The second component may have only one alicyclic heterocycle or two or more alicyclic heterocycles. Preferably, the second component has only one alicyclic heterocycle that is a monocyclic or condensed ring, and more preferably, it has only one alicyclic heterocycle that is a condensed ring.

[0083] The heteroatom included as the second component, which is a cyclizing atom in an alicyclic heterocycle, includes, for example, nitrogen, oxygen, and sulfur atoms. Preferably, the second component, as a cyclizing atom, includes either nitrogen or oxygen atoms.

[0084] There is no particular limitation on the number of heteroatoms included as cyclizing atoms in alicyclic heterocycles, but it is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2.

[0085] There is no particular limitation on the number of ring elements in the monocyclic rings constituting the alicyclic heterocycle (in the case of a condensed ring, each monocyclic ring constituting the alicyclic heterocycle), for example, 5 to 8, preferably 5 to 7, more preferably 5 or 6, and even more preferably 6.

[0086] Monocyclic rings, i.e. alicyclic heterocycles or condensed rings, i.e. alicyclic heterocycles, which constitute the second component, include, for example, rings containing nitrogen atoms as cyclic atoms, such as pyrrolidine, piperidine, piperazine, hexahydropyrimidine, hexahydropyridazine, 1,2,3,6-tetrahydropyrazine, 1,4,5,6-tetrahydropyrimidine, aziridine, aziridine, and hexahydro-1H-1,4-diazazoline, as well as rings containing oxygen atoms as cyclic atoms, such as tetrahydrofuran, tetrahydropiperanan, and oxacyclohexane.

[0087] Alicyclic heterocycles that contain at least one condensed ring of an alicyclic hydrocarbon include, for example, cyclopentane, cyclohexane and cycloheptane.

[0088] Preferably, the second component is a condensation ring consisting of two or three monocyclic rings as illustrated above, more preferably a condensation ring consisting of two monocyclic rings as illustrated above, and even more preferably a condensation ring consisting of a monocyclic ring containing a nitrogen atom as one of the cyclic atoms as illustrated above, or a condensation ring consisting of a monocyclic ring containing an oxygen atom as one of the cyclic atoms as illustrated above and one alicyclic hydrocarbon as illustrated above.

[0089] The second component has an alicyclic heterocycle with hydroxyl groups as substituents.

[0090] The second component has, for example, 1 to 3 hydroxyl groups, preferably 1 or 2, and more preferably 1.

[0091] In addition, the aforementioned hydroxyl groups are substituted for the cyclizing atoms of the alicyclic heterocycles constituting the second component.

[0092] The alicyclic heterocycle of the second component may have substituents other than hydroxyl groups. Examples of substituents other than hydroxyl groups include aliphatic hydrocarbon groups, amino groups, oxo groups, and ketone groups having 1 to 5 carbon atoms, with amino or oxo groups being preferred.

[0093] The number of substituents other than hydroxyl groups in the second component is, for example, 0 to 2, preferably 0 or 1, more preferably 0. That is, it is preferable that the second component does not have substituents other than hydroxyl groups.

[0094] As a second component, for example, compounds represented by formula (1) and compounds represented by formula (2) can be cited.

[0095] [Chemical Formula 1]

[0096]

[0097] In formulas (1) and (2), X independently represents an oxygen atom, an imino atom, or an imino atom with a substituent, and n represents an integer from 1 to 3.

[0098] Here, "imino" is simply represented as an unsubstituted imino (-NH-). Examples of substituents in an imino having the substituent represented by X include hydroxyl groups and substituents other than the hydroxyl group. The preferred manner of the substituents other than the hydroxyl group in the imino is the same as the preferred manner of the substituents other than the hydroxyl group described above.

[0099] Preferably, X is an oxygen atom or an imino group (-NH-). More preferably, X in formula (1) is an imino group, and more preferably, X in formula (2) is an oxygen atom.

[0100] Preferably, n is 1 or 2, and more preferably 1.

[0101] In the compounds represented by formula (1) and formula (2), it is preferred that a hydroxyl group replaces (bonded to) a carbon atom contained in a ring containing X as a cyclizing atom.

[0102] The second component can be used alone or in combination with two or more components.

[0103] The content of the second component is not particularly limited, but is preferably 0.0001 to 5% by mass relative to the total mass of the treatment liquid, more preferably 0.001 to 0.5% by mass.

[0104] From the viewpoint of achieving a good balance between suppressing the surface roughness of the Co-containing film and suppressing defects caused by particulate foreign matter (hereinafter also referred to as "particle defects") caused by the treatment liquid, the ratio (mass ratio) of the content of the second component to the content of the first component (content of the second component / content of the first component) is preferably 0.01 to 1000, more preferably 0.1 to 50.

[0105] [Any ingredient]

[0106] In addition to the components mentioned above, the treatment solution may also contain any other components. Examples of such components include chelating agents, organic solvents, preservatives, hydroxylamine compounds, inorganic acids, surfactants, and various additives.

[0107] The preferred treatment solution contains at least one selected from chelating agents, organic solvents, preservatives, and hydroxylamine compounds.

[0108] The following is a description of any of the components.

[0109] <Chlorinating Agent>

[0110] The treatment solution may contain a chelating agent, and from the viewpoint of better suppression of particle defects, it is preferable to contain a chelating agent.

[0111] Chelating agents are compounds that have the function of chelating with metal ions contained in the residue. Preferably, they are compounds having two or more functional groups (ligands) that are coordinated with metal ions in one molecule.

[0112] Examples of ligands in chelating agents include acid groups and cationic groups. Examples of acid groups include carboxylic acid groups, phosphonic acid groups, phosphate groups, sulfonic acid groups, and hydroxyl groups, with carboxylic acid groups or phosphonic acid groups being preferred. Examples of cationic groups include amino groups.

[0113] Preferably, the chelating agent is a carboxylic acid chelating agent having at least one carboxylic acid group or a phosphonic acid chelating agent having at least one phosphonic acid group.

[0114] The chelating agent preferably has 15 or fewer carbon atoms, more preferably 12 or fewer, and even more preferably 9 or fewer. There is no particular limitation on the lower limit, but 2 or more is preferred.

[0115] (Carboxylic acid chelating agents)

[0116] Examples of carboxylic acid chelating agents include polycarboxylic acid chelating agents, polyaminopolycarboxylic acid chelating agents, and amino acid chelating agents.

[0117] Polycarboxylic acid chelating agents are compounds having multiple carboxylic acid groups in one molecule. However, polyamino-polycarboxylic acid chelating agents and amino acid chelating agents, which will be discussed later, are not included in polycarboxylic acids.

[0118] Examples of polycarboxylic acid chelating agents include citric acid, malonic acid, maleic acid, succinic acid, malic acid, tartaric acid, and citric acid.

[0119] Amino polycarboxylic acid chelating agents are compounds having at least one amino group and multiple carboxylic acid groups in one molecule. Examples include monoalkylene or polyalkylene polyamine polycarboxylic acid, polyaminoalkane polycarboxylic acid, polyaminoalkanol polycarboxylic acid, and hydroxyalkyl ether polyamine polycarboxylic acid.

[0120] Examples of amino polycarboxylic acid chelating agents include, for example, butanediaminetetraacetic acid, diethylenediaminepentaacetic acid (DTPA), ethylenediaminetetramalonic acid, triethylenetetraaminehexaacetic acid (TTHA), 1,3-diamino-2-hydroxypropane-N,N,N',N'-tetraacetic acid, propylenediaminetetraacetic acid, ethylenediaminetetraacetic acid (EDTA), trans-1,2-diaminocyclohexanetetraacetic acid (Cy-DTA), ethylenediaminediacetic acid (EDDA), ethylenediaminedimalonic acid, and 1,6-hexamethylenediaminetetraacetic acid. N,N,N',N'-tetraacetic acid, N,N-bis(2-hydroxybenzyl)ethylenediamine-N,N-diacetic acid, diaminopropanetetraacetic acid, 1,4,7,10-tetraazacyclododecane-tetraacetic acid, diaminopropanoltetraacetic acid, (hydroxyethyl)ethylenediaminetriacetic acid, hydroxyethyliminodiacetic acid (HIDA), iminodiacetic acid (IDA), nitrotriacetic acid (NTA), ethylene glycol ether diaminetetraacetic acid (GEDTA), and N,N-bis(2-hydroxyethyl)glycine (DHEG).

[0121] Among them, DTPA, EDTA, HIDA, DHEG, Cy-DTA, IDA or NTA are preferred, and DTPA, EDTA, and more preferably HIDA or DHEG are preferred.

[0122] Examples of amino acid chelating agents include, for example, glycine, serine, α-alanine (2-aminopropionic acid), β-alanine (3-aminopropionic acid), L-lysine, leucine, isoleucine, cystine, ethionine, threonine, tryptophan, tyrosine, valine, histidine, histidine derivatives, asparagine, aspartic acid, glutamine, glutamic acid, L-arginine, proline, methionine, phenylalanine, and compounds described in paragraphs

[0021] to

[0023] of Japanese Patent Application Publication No. 2016-086094, and their salts.

[0123] Furthermore, as histidine derivatives, compounds described in Japanese Patent Application Publication Nos. 2015-165561 and 2015-165562, etc., can be cited, and these contents are incorporated into this specification. Moreover, as salts, examples include alkali metal salts such as sodium and potassium salts, ammonium salts, carbonates, and acetates.

[0124] (phosphonic acid chelating agents)

[0125] Phosphonic acid chelating agents are chelating agents having at least one phosphonic acid group in the molecule. Preferably, the phosphonic acid chelating agent has 2 to 5 phosphonic acid groups, more preferably 2, 4 or 5, and even more preferably 2 or 5.

[0126] Phosphonic acid chelating agents may have a ligand in addition to the phosphonic acid group. When a phosphonic acid chelating agent has an amino group as a ligand, it is preferable that there are 1 to 4 amino groups, more preferably 2 or 3.

[0127] Examples of phosphonic acid chelating agents include, for example, ethylene diphosphonic acid, 1-hydroxyethylene-1,1'-diphosphonic acid (HEDP), 1-hydroxypropylidene-1,1'-diphosphonic acid, 1-hydroxybutylidene-1,1'-diphosphonic acid, ethylaminobis(methylenephosphonic acid), dodecylaminobis(methylenephosphonic acid), nitrogen mono(methylenephosphonic acid) (NTMP), ethylenediaminebis(methylenephosphonic acid) (EDDP), 1,3-propylidenediaminebis(methylenephosphonic acid), N,N, N',N'-ethylenediaminetetra(methylenephosphonic acid) (EDTMP), ethylenediaminetetra(methylenephosphonic acid), 1,3-propylenediaminetetra(methylenephosphonic acid) (PDTMP), 1,2-diaminopropanetetra(methylenephosphonic acid), 1,6-hexamethylenediaminetetra(methylenephosphonic acid), diethylenetriaminepenta(methylenephosphonic acid) (DEPPO), diethylenetriaminepenta(methylenephosphonic acid), triethylenetetraminehexa(methylenephosphonic acid), and triethylenetetraminehexa(methylenephosphonic acid).

[0128] Furthermore, as a phosphonic acid chelating agent, the compounds described in paragraphs

[0026] to

[0036] of International Publication No. 2018 / 020878 and the compounds described in paragraphs

[0031] to

[0046] of International Publication No. 2018 / 030006 (copolymers) can be used, and these contents are incorporated into this specification.

[0129] As phosphonic acid chelating agents, HEDP, NTMP, DTMP, PDTMP or EDDP are preferred, with HEDP, more preferably NTMP or DTMP.

[0130] Phosphoric acid chelating agents with phosphate groups include, for example, condensed phosphate and its salts, as well as organic compounds having two or more phosphate groups (phosphate ester groups) (but excluding compounds that function as surfactants as described later).

[0131] Specific examples of phosphate chelating agents include pyrrolic phosphoric acid, metaphosphoric acid, tripolyphosphoric acid, tetrapolyphosphoric acid, hexametaphosphoric acid, phytic acid, and their salts.

[0132] As an amine chelating agent, for example, at least one biguanide compound selected from compounds having a biguanide group and their salts can be cited.

[0133] There is no particular limitation on the number of biguanide groups that a biguanide compound can have; it can have multiple biguanide groups.

[0134] As biguanide compounds, examples include those described in paragraphs

[0034] to

[0055] of Japanese Patent Publication No. 2017-504190, which are incorporated herein by reference.

[0135] Chelating agents can be used alone or in combination of two or more.

[0136] When the treatment solution contains a chelating agent, from the viewpoint of achieving a better balance between cleaning performance and corrosion prevention, the content of the chelating agent relative to the total mass of the treatment solution is preferably 0.01 to 10.0% by mass, more preferably 0.05 to 2.0% by mass.

[0137] As a chelating agent, a chelating agent that has undergone purification treatment is preferred.

[0138] There are no particular limitations on the purification methods used as chelating agents. For example, known methods such as filtration, ion exchange, distillation, adsorption purification, recrystallization, recrystallization, sublimation, and purification using a column, as well as combinations of these methods, can be cited. Among these, the method of obtaining a purified product containing a chelating agent by subjecting the raw material containing the chelating agent to the purification treatment described below is preferred.

[0139] <Organic Solvents>

[0140] The treatment solution may contain organic solvents, and preferably contains organic solvents.

[0141] There are no particular limitations on the type of organic solvent, but hydrophilic organic solvents are preferred. Furthermore, in this specification, a hydrophilic organic solvent refers to an organic solvent that dissolves at least 0.1 g in 100 g of water at 25°C. Preferably, the hydrophilic organic solvent is one that can be uniformly mixed with water in any proportion.

[0142] As a hydrophilic organic solvent, it is preferably selected from at least one of glycol solvents, glycol ether solvents, amide solvents, alcohol solvents and sulfoxide solvents.

[0143] There are no particular limitations on diol solvents; examples include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, and tetraethylene glycol.

[0144] There are no particular limitations on its use as a solvent for glycol ethers; for example, glycol monoethers can be cited.

[0145] Examples of glycol monoethers include, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, 1-methoxy-2-propanol, 2-methoxy-1-propanol, 1-ethoxy-2-propanol, 2-ethoxy-1-propanol, propylene glycol mono-n-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monobenzyl ether, and diethylene glycol monobenzyl ether.

[0146] There are no particular limitations on amide solvents, and examples include N,N-dimethylformamide, 1-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolium ketone, 2-pyrrolidone, formamide, N-methylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropionamide, and hexamethylphosphoric triamine.

[0147] There are no particular limitations on its use as an alcohol solvent, but examples include alkanediols, alkoxy alcohols, saturated aliphatic monohydric alcohols, and unsaturated non-aromatic monohydric alcohols.

[0148] Examples of alkanediols include, for example, diols, 2-methyl-1,3-propanediol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 2,3-butanediol, and pinacol.

[0149] Examples of alkoxy alcohols include, for example, 3-methoxy-3-methyl-1-butanol, 3-methoxy-1-butanol, 1-methoxy-2-butanol, and diol monoethers.

[0150] Examples of saturated aliphatic monohydric alcohols include, for example, methanol, ethanol, n-propanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 2-pentanol, tert-pentanol, and 1-hexanol.

[0151] Examples of unsaturated non-aromatic monohydric alcohols include allyl alcohol, propargyl alcohol, 2-butenol, 3-butenol and 4-penten-2-ol.

[0152] Examples of low molecular weight alcohols containing cyclic structures include tetrahydrofurfuryl alcohol, furfuryl alcohol, and 1,3-cyclopentanediol.

[0153] Examples of sulfoxide solvents include dimethyl sulfoxide.

[0154] From the viewpoint of achieving better results with respect to hydrophilic organic solvents, glycol ether solvents are preferred.

[0155] Organic solvents can be used alone or in combination of two or more.

[0156] When the treatment solution contains an organic solvent, from the viewpoint of achieving better results according to the present invention, the content of the organic solvent relative to the total mass of the treatment solution is preferably 50% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less. There is no particular limitation on the lower limit, but it is preferably 0.1% by mass or more relative to the total mass of the treatment solution, more preferably 1.0% by mass or more.

[0157] <Preservatives>

[0158] The treatment solution may contain preservatives, preferably preservatives.

[0159] The corrosion inhibitor has the function of forming a film by coordinating with the surface of the metal layer (especially the Co-containing layer) of the wiring of semiconductor devices and preventing corrosion of the metal layer caused by excessive etching, etc.

[0160] In addition, the chelating agents (compounds with chelating ability) mentioned above are not included in the preservatives in this specification.

[0161] Examples of preservatives include compounds represented by formula (A), formula (B), formula (C), and substituted or unsubstituted tetrazolium.

[0162] More specific examples of preservatives include 1H-1,2,4-triazole (124TZ), 5-aminotetrazole (ATA), 5-amino-1,3,4-thiadiazole-2-thiol, 3-amino-1H-1,2,4-triazole, 3,5-diamino-1,2,4-triazole, tolyltriazole, 3-amino-5-mercapto-1,2,4-triazole, 1-amino-1,2,4-triazole, 1-amino-1,2,3-triazole, 1-amino-5-methyl-1,2,3-triazole, and 3-mercapto-1,2,4-triazole. 1,2,4-triazole, 3-isopropyl-1,2,4-triazole, naphthiatriazole, 1H-tetrazole-5-acetic acid, 2-mercaptobenzothiazole (2-MBT), 1-phenyl-2-tetrazolin-5-thione, 2-mercaptobenzimidazole (2-MBI), 4-methyl-2-phenylimidazolium, 2-mercaptothiazoline, 2,4-diamino-6-methyl-1,3,5-triazine, thiazole, imidazole, benzimidazole, triazine, methyltetrazole, dithiol I, 1,3-dimethyl-2-imidazolidineone, 1,5- Pentamethylenetetrazolium, 1-Phenylacetetrazol, Diaminomethyltriazine, Imidazolinethione, 4-Methyl-4H-1,2,4-triazol-3-thiol, 5-Amino-1,3,4-thiadiazol-2-thiol, Benzothiazole, Trimethylmethyl phosphate, Indazole, Adenine, Cytosine, Guanine, Thymine, Phosphate inhibitors, Pyrazoles, Propanethiols, Silanes, Benzohydroxyoxime acids, Heterocyclic nitrogen inhibitors, Thiourea, 1,1,3,3-Tetramethylurea, Urea, Urea derivatives, Uric acid, Potassium ethyl xanthate Dodecylphosphonic acid, iminodiacetic acid, boric acid, azirmonotriacetic acid, sulfolane, 2,3,5-trimethylpyrazine, 2-ethyl-3,5-dimethylpyrazine, quinoxaline, acetylpyrrole, pyridazine, histidine, pyrazine, glutathione (reduced form), cystine, thiophene, mercaptopyridine N-oxide, thiamine HCl, tetraethylamine disulfide methylthioyl, 2,5-dimercapto-1,3-thiadiazole ascorbic acid, ascorbic acid, catechol, tert-butylcatechol, phenol, and gallophenol.

[0163] Examples of preservatives include substituted or unsubstituted benzotriazoles (hereinafter also referred to as "benzotriazole compounds"). As substituted benzotriazoles, those substituted with alkyl, aryl, halogen, amino, nitro, alkoxy, or hydroxyl groups are preferred. Substituted benzotriazoles also contain groups formed by condensation with one or more aryl (e.g., phenyl) or heteroaryl groups.

[0164] Examples of benzotriazole compounds suitable as preservatives include benzotriazole (BTA), 5-aminotetrazole, 1-hydroxybenzotriazole, 5-phenylthio-benzotriazole, 5-chlorobenzotriazole, 4-chlorobenzotriazole, 5-bromobenzotriazole, 4-bromobenzotriazole, 5-fluorobenzotriazole, 4-fluorobenzotriazole, naphthyltriazole, tolyltriazole, 5-phenyl-benzotriazole, 5-nitrobenzotriazole, 4-nitrobenzotriazole, 3-amino-5-mercapto-1,2,4-triazole, 2-(5-amino-pentyl)-benzotriazole, 1-amino-benzotriazole, 5-methyl-1H-benzotriazole (5MBTA), benzotriazole-5-carboxylic acid, 4-methylbenzotriazole, 4-ethylbenzotriazole, 5-ethylbenzotriazole, and 4-propylbenzene. 5-Propylbenzotriazole, 4-Isopropylbenzotriazole, 5-Isopropylbenzotriazole, 4-n-Butylbenzotriazole, 5-n-Butylbenzotriazole, 4-Isobutylbenzotriazole, 5-Isobutylbenzotriazole, 4-Pentylbenzotriazole, 5-Pentylbenzotriazole, 4-Hexylbenzotriazole, 5-Hexylbenzotriazole, 5-Methoxybenzotriazole, 5-Hydroxybenzotriazole Dihydroxypropylbenzotriazole, 1-[N,N-bis(2-ethylhexyl)aminomethyl]-benzotriazole, 5-tert-butylbenzotriazole, 5-(1',1'-dimethylpropyl)-benzotriazole, 5-(1',1',3'-trimethylbutyl)benzotriazole, 5-n-octylbenzotriazole and 5-(1',1',3',3'-tetramethylbutyl)benzotriazole.

[0165] Furthermore, examples of benzotriazole compounds include 2,2'-{[(4-methyl-1H-benzotriazole-1-yl)methyl]imino} diethanol, 2,2'-{[(5-methyl-1H-benzotriazole-1-yl)methyl]imino} diethanol, 2,2'-{[(4-methyl-1H-benzotriazole-1-yl)methyl]imino} diethane or 2,2'-{[(4-methyl-1H-benzotriazole-1-yl)methyl]imino} dipropane and N,N-bis(2-ethylhexyl)-(4 or 5)-methyl-1H-benzotriazole-1-methylamine.

[0166] From the viewpoint of achieving better results with the present invention, it is preferred that the treatment solution contains at least one compound selected from the compound represented by formula (A), the compound represented by formula (B), the compound represented by formula (C), and substituted or unsubstituted tetrazolium.

[0167] [Chemical Formula 2]

[0168]

[0169] In the above formula (A), R 1A ~R 5AEach of the following groups independently represents a hydrogen atom, a substituted or unsubstituted hydrocarbon group, a hydroxyl group, a carboxyl group, or a substituted or unsubstituted amino group. The structure contains at least one group selected from hydroxyl, carboxyl, and substituted or unsubstituted amino groups.

[0170] In the above formula (B), R 1B ~R 4B Each can be used independently to represent a hydrogen atom or a substituted or unsubstituted hydrocarbon group.

[0171] In the above formula (C), R 1C R 2C and R N Each can independently represent a hydrogen atom or a substituted or unsubstituted hydrocarbon group. Furthermore, R... 1C Can be used with R 2C They bond together to form a ring.

[0172] In the above formula (A), R is... 1A ~R 5A Examples of hydrocarbon groups include alkyl groups (preferably with 1 to 12 carbon atoms, more preferably with 1 to 6 carbon atoms, and even more preferably with 1 to 3 carbon atoms), alkenyl groups (preferably with 2 to 12 carbon atoms, more preferably with 2 to 6 carbon atoms), alkynyl groups (preferably with 2 to 12 carbon atoms, more preferably with 2 to 6 carbon atoms), aryl groups (preferably with 6 to 22 carbon atoms, more preferably with 6 to 14 carbon atoms, and even more preferably with 6 to 10 carbon atoms) and aralkyl groups (preferably with 7 to 23 carbon atoms, more preferably with 7 to 15 carbon atoms, and even more preferably with 7 to 11 carbon atoms).

[0173] Furthermore, examples of substituents that can be used to replace hydrocarbon groups include hydroxyl groups, carboxyl groups, and substituted or unsubstituted amino groups (preferably alkyl groups with 1 to 6 carbon atoms, and more preferably alkyl groups with 1 to 3 carbon atoms when substituents are used to replace amino groups).

[0174] In addition, in formula (A), the structure contains at least one group selected from hydroxyl, carboxyl and substituted or unsubstituted amino groups (preferably alkyl groups with 1 to 6 carbon atoms, more preferably alkyl groups with 1 to 3 carbon atoms when substituted amino groups are used).

[0175] In equation (A), R is... 1A ~R 5A The substituted or unsubstituted hydrocarbon group represented may include, for example, hydrocarbon groups with 1 to 6 carbon atoms substituted with hydroxyl, carboxyl or amino groups.

[0176] Examples of compounds represented by formula (A) include 1-thioglycerol, L-cysteine, and thiomalic acid.

[0177] In equation (B), R 1B ~R 4BThe meaning of the substituted or unsubstituted hydrocarbon group is the same as that of R in formula (A) above. 1A ~R 5A The meanings of substituted and unsubstituted hydrocarbon groups are the same.

[0178] As R 1B ~R 4B The substituted or unsubstituted hydrocarbon group can be exemplified by hydrocarbon groups with 1 to 6 carbon atoms, such as methyl, ethyl, propyl and tert-butyl.

[0179] Examples of compounds represented by formula (B) include, for example, catechol and tert-butylcatechol.

[0180] In equation (C), R is used as 1C R 2C and R N The substituted or unsubstituted hydrocarbon group represented is the same as R in formula (A) above. 1A ~R 5A The meanings of substituted and unsubstituted hydrocarbon groups are the same.

[0181] As R 1C R 2C and R N The substituted or unsubstituted hydrocarbon group can be exemplified by hydrocarbon groups with 1 to 6 carbon atoms, such as methyl, ethyl, propyl, and butyl.

[0182] Furthermore, R 1C Can be used with R 2C They bond together to form a ring. As R 1C With R 2C A ring formed by bonding, for example, a benzene ring. R 1C With R 2C In the case of bonding to form a ring, it may also have substituents (e.g., hydrocarbon groups with 1 to 5 carbon atoms).

[0183] Examples of compounds represented by formula (C) include 1H-1,2,3-triazole (123TZ), benzotriazole (BTA), 5-methyl-1H-benzotriazole (5M-BTA), tolyltriazole, 2,2'-{[(4-methyl-1H-benzotriazole-1-yl)methyl]imino}diethanol (trade name "IRGAMET 42", manufactured by BASF), N,N-bis(2-ethylhexyl)-(4 or 5)-methyl-1H-benzotriazole-1-methylamine (trade name "IRGAMET 39", manufactured by BASF), etc. From the viewpoint of excellent effects achieved by the present invention, 1H-1,2,3-triazole, benzotriazole, 5-methyl-1H-benzotriazole or tolyltriazole are preferred.

[0184] Examples of substituted or unsubstituted tetrazolium include tetrazolium with an unsubstituted tetrazolium and a hydroxyl, carboxyl, or substituted or unsubstituted amino group as a substituent. Among these, when the amino group is substituted, an alkyl group having 1 to 6 carbon atoms is preferred, and an alkyl group having 1 to 3 carbon atoms is more preferred.

[0185] Preservatives can be used alone or in combination of two or more.

[0186] When the treatment solution contains a preservative, the content of the preservative in the treatment solution relative to the total mass of the treatment solution is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% by mass, and even more preferably 0.1 to 1% by mass.

[0187] Regarding preservatives, high-purity grades are preferred, and even more preferably, they should be used after further purification.

[0188] There are no particular limitations on the purification methods for preservatives. For example, known methods such as filtration, ion exchange, distillation, adsorption purification, recrystallization, reprecipitation, sublimation, and purification using a column can be used, and these methods can also be combined.

[0189] <Hydramine compounds>

[0190] From the viewpoint of superior performance in removing residues, the treatment solution may contain at least one hydroxylamine compound selected from hydroxylamine (NH2OH), hydroxylamine derivatives and their salts, preferably containing the aforementioned hydroxylamine compound.

[0191] Hydroxylamine compounds promote the decomposition and solubility of residues, and also produce etched residues and ashing residues.

[0192] There are no particular limitations on what constitutes a hydroxylamine derivative. Examples include O-methylhydroxylamine, O-ethylhydroxylamine, N-methylhydroxylamine, N,N-dimethylhydroxylamine, N,O-dimethylhydroxylamine, N-ethylhydroxylamine, N,N-diethylhydroxylamine, N,O-diethylhydroxylamine, O,N,N-trimethylhydroxylamine, N,N-dicarboxyethylhydroxylamine, and N,N-disulfoethylhydroxylamine.

[0193] Salts of hydroxylamine (NH2OH) and its derivatives are preferably inorganic or organic acid salts of the aforementioned hydroxylamine (NH2OH) and its derivatives. Salts of inorganic acids formed by the bonding of non-metallic atoms such as Cl, S, N, or P with hydrogen atoms are more preferred. Salts of any one of hydrochloric acid, sulfuric acid, or nitric acid are even more preferred.

[0194] As inorganic acid salts of hydroxylamine (NH2OH) and hydroxylamine derivatives, hydroxylamine nitrate, hydroxylamine sulfate, hydroxylamine hydrochloride, hydroxylamine phosphate, N,N-diethylhydroxylamine sulfate, N,N-diethylhydroxylamine nitrate, or mixtures thereof are preferred.

[0195] Organic acid salts of hydroxylamine (NH2OH) and its derivatives include, for example, hydroxyl ammonium citrate, hydroxyl ammonium oxalate, and hydroxyl ammonium polyvinylidene fluoride.

[0196] From the viewpoint of superior residue removal, hydroxylamine (NH2OH) is preferred as a hydroxylamine compound.

[0197] Hydroxylamine compounds can be used alone or in combination of two or more.

[0198] When the treatment solution contains a hydroxylamine compound, from the viewpoint of better performance in suppressing particle defects, the content of the hydroxylamine compound relative to the total mass of the treatment solution is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass.

[0199] <pH adjuster>

[0200] To adjust the pH of the treatment solution, a pH adjuster may be included.

[0201] As pH adjusters, acidic and basic compounds can be cited.

[0202] (Acidic compound)

[0203] Acidic compounds may be included in the treatment solution as pH adjusters.

[0204] Acidic compounds can be inorganic acids or organic acids (except for the chelating agents mentioned above).

[0205] The preferred treatment solution contains an inorganic acid. Examples of inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, boric acid, phosphonic acid, and phosphoric acid, with hydrochloric acid, phosphoric acid, or sulfuric acid being preferred. Examples of organic acids include formic acid, acetic acid, propionic acid, and butyric acid, which are lower (1-4 carbon atoms) aliphatic monocarboxylic acids. Furthermore, the aforementioned chelating agents can also function as acidic compounds.

[0206] (Alkaline compounds)

[0207] The treatment solution may contain alkaline compounds as pH adjusters. Alkaline compounds are those whose pH is 9 or higher when 1g of the compound is dissolved in 100g of water.

[0208] Furthermore, in this specification, the compounds contained in the first component, the second component, and the amine chelating agent are not included in the basic compounds.

[0209] Examples of basic compounds include ammonium hydroxide, water-soluble amines, and quaternary ammonium salts.

[0210] In this specification, water-soluble amines refer to amines that can dissolve more than 50g in 1L of water. The above-mentioned substances are not included in the category of water-soluble amines.

[0211] Examples of water-soluble amines include primary amines having a primary amino group (-NH2) in the molecule, secondary amines having a secondary amino group (>NH) in the molecule, tertiary amines having a tertiary amino group (>N-) in the molecule, and their salts. Furthermore, water-soluble amines can be compounds having at least one hydroxyl alkyl group in the molecule (amino alcohols).

[0212] Examples of quaternary ammonium salts include quaternary ammonium hydroxides.

[0213] Examples of quaternary ammonium hydroxides include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide, tetrabutylammonium hydroxide (TBAH), methyltripropylammonium hydroxide, methyltributylammonium hydroxide, ethyltrimethylammonium hydroxide, dimethyldiethylammonium hydroxide, benzyltrimethylammonium hydroxide (BzTMAH), hexadecyltrimethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide, and spiro-(1,1')-bipyrrolidone hydroxide, with TMAH, TEAH, TBAH, or BzTMAH being preferred.

[0214] pH adjusters can be used alone or in combination of two or more.

[0215] Regarding the type and content of pH adjusters, the appropriate type of pH adjuster (acidic compound and basic compound) should be selected to adjust the content so that the pH of the treatment solution is within the preferred range described later.

[0216] When the treatment solution contains a pH adjuster, its content relative to the total mass of the treatment solution is preferably 0.01 to 20% by mass, more preferably 0.01 to 10% by mass.

[0217] The treatment fluid may contain additives in addition to the components mentioned above. Examples of additives include surfactants, defoamers, and rust inhibitors.

[0218] The contents of the above-mentioned components in the treatment solution can be determined by known methods such as gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), and ion-exchange chromatography (IC).

[0219] [Physical properties of the treatment solution]

[0220] <pH>

[0221] The pH of the treatment solution is preferably 5 to 14 at 25°C, more preferably 6 to 11. By keeping the pH of the treatment solution within the above range, the effects of the present invention and residue removal can be achieved at a better level.

[0222] The pH of the treatment solution was obtained by measuring the pH value at 25°C using a known pH meter in accordance with the method of JIS Z8802-1984.

[0223] The pH of the treatment solution can be adjusted by using the pH adjuster described above, as well as any of the components that have the functions of pH adjusters such as the first component and surfactants.

[0224] <Metal content>

[0225] In the processing solution, the content (measured by ion concentration) of each metal (Fe, Co, Na, Cu, Mg, Mn, Li, Al, Cr, Ni, Zn, Sn, and Ag) contained as impurities in the liquid is preferably 5 ppm by mass or less, more preferably 1 ppm by mass or less. In the manufacture of state-of-the-art semiconductor devices, since a higher purity processing solution is assumed to be required, it is further preferred that the metal content be less than 1 ppm by mass, i.e., less than ppb by mass, particularly preferably less than 100 ppb by mass, and most preferably less than 10 ppb by mass. As a lower limit, 0 is preferred.

[0226] The types and contents of metals in the treatment solution can be determined by ICP-MS (Inductively Coupled Plasma Mass Spectrometry).

[0227] As devices for implementing ICP-MS, for example, the Agilent 8900 triple quadrupole ICP-MS (for semiconductor analysis, option #200) manufactured by Agilent Technologies, Inc., the NexION350S manufactured by PerkinElmer, Inc., and the Agilent 8800 manufactured by Agilent Technologies, Inc. can be used.

[0228] As a method to reduce the metal content, examples include purification treatments such as distillation and ion exchange resin or filtration using a filter during the stage of manufacturing the treatment liquid or in a stage after the manufacturing of the treatment liquid.

[0229] As another method to reduce metal content, one example is using a container that minimizes the leaching of the aforementioned impurities as the container for holding raw materials or manufacturing the treatment liquid. Another example is lining the inner wall of the piping with fluoropolymer resin to prevent metal components from leaching out of the piping during the manufacturing of the treatment liquid.

[0230] <Coarse particles>

[0231] The preferred treatment solution may contain coarse particles, but does not substantially contain coarse particles. "Coarse particles" refers to particles with a diameter of 0.2 μm or more when the particle shape is set as spheres. Furthermore, "substantially not containing coarse particles" means that when the treatment solution is measured using a commercially available measuring device in a light scattering liquid particle determination method, the number of particles larger than 0.2 μm in 1 mL of the treatment solution is 10 or less.

[0232] In addition, the coarse particles contained in the treatment liquid are particles such as dust, smog, organic solid matter and inorganic solid matter contained as impurities in the raw materials, as well as particles such as dust, smog, organic solid matter and inorganic solid matter that are introduced as pollutants during the preparation of the treatment liquid. These particles are equivalent to existing as particles that are not dissolved in the final treatment liquid.

[0233] Furthermore, the preferred processing solution does not contain abrasive particles.

[0234] The amount of coarse particles present in the processing liquid can be measured in the liquid phase using a commercially available measuring device that uses a laser as a light scattering liquid particle measurement method.

[0235] Methods for removing coarse particles include, for example, screening.

[0236] [Preparation of the treatment solution]

[0237] <Preparation Process of Treatment Solution>

[0238] There are no particular limitations on the preparation method of the treatment solution, and it can be prepared by known methods. For example, the treatment solution can be prepared by mixing the above-mentioned components.

[0239] Regarding the order and / or timing of mixing the above components, for example, it can be prepared by the following method: In a container filled with purified pure water, the first and second components, along with any desired chelating agents, organic solvents, and preservatives, are added sequentially, followed by stirring to mix. The pH of the mixture is then adjusted by adding a pH adjuster as needed. When adding water and the components to the container, they can be added all at once or in multiple additions.

[0240] In the preparation of the treatment liquid, any known device can be used as a mixer or disperser. Examples of mixers include industrial mixers, portable mixers, mechanical mixers, and electromagnetic mixers. Examples of dispersers include industrial dispersers, homogenizers, ultrasonic dispersers, and bead mills.

[0241] The mixing of the components and the subsequent purification process in the preparation of the preferred treatment solution, as well as the storage of the prepared treatment solution, are preferably carried out at a temperature below 40°C, more preferably at a temperature below 30°C. Furthermore, as a lower limit, it is preferably at a temperature of 5°C or higher, more preferably at a temperature of 10°C or higher. By preparing the treatment solution within the above temperature range, and then processing and / or storing it, the performance can be maintained stably for a long period of time.

[0242] <Purification Process>

[0243] Preferably, one or more of the raw materials used to prepare the treatment solution are purified beforehand. Examples of purification methods include, for instance, distillation, ion exchange, and filtration (screening).

[0244] Regarding the degree of purification, it is preferable to purify until the purity of the stock solution is 99% by mass or more, and more preferably until the purity of the raw material is 99.9% by mass or more. As an upper limit, it is preferably 99.9999% by mass or less.

[0245] Methods for purification include, for example, passing the feedstock through an ion exchange resin or a reverse osmosis membrane, distillation of the feedstock, and screening as described later.

[0246] As a purification process, multiple of the above-mentioned purification methods can be combined. For example, after the raw material is purified by passing the solution through an RO membrane, a second purification process can be performed by passing the solution through a purification device consisting of a cation exchange resin, an anion exchange resin, or a mixed-bed ion exchange resin.

[0247] Furthermore, the purification process can be performed multiple times.

[0248] (filter)

[0249] As a filter used for screening, well-known filters for filtration can be cited. For example, filters composed of fluoropolymers such as polytetrafluoroethylene (PTFE) and tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA), polyamide resins such as nylon, and polyolefin resins such as polyethylene and polypropylene (PP) (including high-density or ultra-high molecular weight) can be cited.

[0250] Among these materials, those selected are preferably from the group consisting of polyethylene, polypropylene (including high-density polypropylene), fluoropolymers (including PTFE and PFA), and polyamide resins (including nylon), with fluoropolymer filters being more preferred. By using filters formed from these materials to filter raw materials, highly polar foreign matter that is prone to causing defects can be effectively removed.

[0251] The critical surface tension of the filter is preferably 70 to 95 mN / m, more preferably 75 to 85 mN / m. Furthermore, the critical surface tension value of the filter is the nominal value specified by the manufacturer. By using a filter with a critical surface tension within the above range, highly polar foreign matter, which is prone to causing defects, can be effectively removed.

[0252] The pore size of the filter is preferably 2–20 nm, more preferably 2–15 nm. By setting it within this range, filter clogging can be suppressed, and fine foreign matter such as impurities and agglomerates contained in the raw material can be reliably removed. The pore size here can be referenced from the nominal value of the filter manufacturer.

[0253] Filtering can be performed once or more. When filtering more than once, the filters used can be the same or different.

[0254] Furthermore, the screening temperature is preferably below room temperature (25°C), more preferably below 23°C, and even more preferably below 20°C. It is also preferably above 0°C, more preferably above 5°C, and even more preferably above 10°C. By performing screening within the above temperature range, the amount of particulate foreign matter and impurities dissolved in the raw materials can be reduced, and foreign matter and impurities can be effectively removed.

[0255] [Processing fluid containment body]

[0256] The treatment fluid can be contained in a container and stored until it is used.

[0257] This container and the processing liquid contained within it are collectively referred to as a processing liquid container. The processing liquid is retrieved from the stored processing liquid container and used. Furthermore, the processing liquid can be transported using the processing liquid container.

[0258] As a container, a container suitable for semiconductor applications is preferred, as it provides high cleanliness and suppresses the leaching of impurities from the inner wall of the container's containment section into each liquid. Examples of such containers include various commercially available containers for semiconductor processing liquids, such as the "Clean-Bottle" series manufactured by AICELLO CHEMICAL CO.,LTD. and the "Pure bottle" manufactured by KODAMA PLASTICS Co.,Ltd., but are not limited to these.

[0259] The inner wall of the preferred container is formed of one or more resins selected from polyethylene resin, polypropylene resin, and polyethylene-polypropylene resin, or a different resin. Furthermore, the inner wall of the preferred container is also formed of a metal treated with rust prevention and metal leaching prevention measures, such as stainless steel, Hastelloy alloy, Inconel nickel, and Monel alloy.

[0260] Of the aforementioned different resins, fluoropolymers (perfluorinated resins) are preferred. Thus, by using a container with an inner wall made of fluoropolymer, compared to a container with an inner wall made of polyethylene resin, polypropylene resin, or polyethylene-polypropylene resin, it is possible to suppress undesirable conditions such as the leaching of oligomers of ethylene or propylene.

[0261] For example, the FluoroPure PFA composite roller manufactured by Entegris can be used as a container with an inner wall of fluoropolymer. Furthermore, containers described in Japanese Patent Application Publication No. 3-502677 (page 4), International Publication No. 2004 / 016526 (page 3), and International Publication No. 99 / 046309 (pages 9 and 16) can also be used.

[0262] Furthermore, in addition to the aforementioned fluororesin, the inner wall of the container can preferably be made of quartz and electrolytically polished metal materials (i.e., metal materials that have undergone electrolytic polishing).

[0263] The metal material used in the manufacture of the aforementioned electrolytically ground metal material includes at least one selected from chromium and nickel, preferably a metal material in which the total content of chromium and nickel is more than 25% by mass relative to the total mass of the metal material, for example, stainless steel and nickel-chromium alloys.

[0264] More preferably, the combined content of chromium and nickel in the metallic material is 30% by mass or more relative to the total mass of the metallic material. As an upper limit, it is preferably 90% by mass or less.

[0265] As a method for electrolytically polishing metallic materials, known methods can be used. For example, the methods described in paragraphs

[0011] to

[0014] of Japanese Patent Application Publication No. 2015-227501 and paragraphs

[0036] to

[0042] of Japanese Patent Application Publication No. 2008-264929 can be used.

[0266] Preferably, the interior of these containers is cleaned before being filled with the treatment solution. Regarding the cleaning solution, it is preferable that the amount of metallic impurities in the solution is reduced. The treatment solution can be bottled in containers such as gallon bottles or coated bottles after manufacturing for transport and storage.

[0267] To prevent changes in the composition of the processing liquid during storage, the container can be filled with an inert gas (such as nitrogen or argon) with a purity of 99.99995% by volume or higher. In particular, a gas with low water content is preferred. Furthermore, transportation and storage can be carried out at room temperature, but the temperature can also be controlled within a range of -20°C to 20°C to prevent deterioration.

[0268] (Cleanroom)

[0269] The preferred processes, including the manufacture of the treatment solution, the opening and cleaning of containers, the filling of the treatment solution, the handling, analysis, and measurement, are all carried out in a cleanroom.

[0270] The cleanroom preferably meets the 14644-1 cleanroom standard. More preferably, it meets any one of ISO (International Organization for Standardization) Class 1, ISO Class 2, ISO Class 3, ISO Class 4, ISO Class 5 and ISO Class 6. More preferably, it meets any one of ISO Class 1, ISO Class 2, ISO Class 3 and ISO Class 4. Especially preferably, it meets ISO Class 1 or ISO Class 2. Most preferably, it meets ISO Class 1.

[0271] [use]

[0272] Next, the uses of this treatment solution will be explained.

[0273] This processing solution is for use in semiconductor devices. In this specification, "for semiconductor devices" means for use in the manufacturing process of semiconductor devices. This processing solution can be used in any process used to manufacture semiconductor devices.

[0274] Examples of uses for this processing solution include cleaning solutions used in cleaning semiconductor substrates (semiconductor substrate cleaning solution) and processing solutions used to remove target objects such as metals from semiconductor substrates (semiconductor substrate processing solution).

[0275] As for the aforementioned cleaning solution for semiconductor substrates, there are no particular limitations as long as it is suitable for semiconductor substrates and is used for the purpose of removing metal impurities or particles and other residues attached to the semiconductor substrate. For example, examples include cleaning solutions for semiconductor substrates that have undergone etching treatment (etching residue cleaning solution), cleaning solutions for semiconductor substrates that have undergone chemical mechanical polishing (CMP cleaning solution), cleaning solutions for polishing and cleaning semiconductor substrates that have undergone CMP treatment (polishing cleaning solution), cleaning solutions for cleaning semiconductor substrates that have undergone back-side grinding, and cleaning solutions for semiconductor substrates that use flux to solder electronic components or form solder bumps.

[0276] Examples of processing solutions for semiconductor substrates include etching solutions that dissolve and remove metal-containing substances from semiconductor substrates, pre-wetting solutions that are applied to substrates to improve the coatability of photosensitive or radiosensitive linear processing solutions before the process of forming a resist film using photosensitive or radiosensitive linear processing solutions, and rinsing solutions that rinse substances adhering to semiconductor substrates.

[0277] This treatment solution can be used for one or more of the above applications.

[0278] [Methods for processing the object]

[0279] This treatment solution is used, for example, in a treatment method for a workpiece that includes a step of contacting the workpiece with the treatment solution (hereinafter also referred to as "this treatment method"). As the workpiece to be treated, examples include objects for which the treatment solution described above is used. By using this treatment solution in this treatment method, it is possible to clean the workpiece (remove residues, etc.) or remove one or more metal inclusions present in the workpiece.

[0280] More specifically, examples include cleaning methods that use this treatment solution to remove residues adhering to the object being treated (e.g., methods for cleaning etching residues on a semiconductor substrate). Furthermore, examples include etching methods that use this treatment solution to dissolve and remove metal inclusions on a semiconductor substrate, pre-wetting methods that coat the semiconductor substrate with this treatment solution before forming a resist film using a photosensitive or radiosensitive linear treatment solution, and rinsing methods that use this treatment solution to rinse the semiconductor substrate.

[0281] The object to be processed by this method is not particularly limited as long as it is a component used in the manufacturing process of semiconductor devices; for example, the semiconductor substrate described above can be cited. Among them, a semiconductor substrate having a metal layer is preferred.

[0282] As a metallic layer present in the object being treated, examples include metal monomers and alloys.

[0283] Examples of metal atoms included in the metal layer include cobalt (Co), ruthenium (Ru), tungsten (W), molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), and tantalum (Ta).

[0284] The content of metal atoms in the metal layer relative to the total mass of the metal layer is preferably 30 to 100% by mass, more preferably 40 to 100% by mass, and even more preferably 50 to 100% by mass.

[0285] The preferred metal layer contains cobalt, ruthenium, tungsten, molybdenum, aluminum, copper, titanium or tantalum as the main component, more preferably cobalt or copper as the main component, and even more preferably cobalt as the main component.

[0286] In this specification, for example, "containing cobalt as a main component" means that cobalt is the most abundant metal atom in the metal layer. Examples of metal layers containing cobalt as a main component (hereinafter also referred to as "cobalt-containing layers") include, for example, cobalt monomers (metallic cobalt) and cobalt alloys (alloys in which cobalt is the most abundant metal atom).

[0287] The content of metal atoms (preferably cobalt atoms) contained in the metal layer as the main component is preferably 50 to 100% by mass relative to the total mass of the metal layer, more preferably 80 to 100% by mass, and even more preferably 95 to 100% by mass.

[0288] The manner in which the metal layer in the processed object is configured is not particularly limited; for example, it can be configured as a film (including a metal film) or as a wiring (including a metal wiring film).

[0289] When the metal layer is in the form of a film or wiring, its thickness is not particularly limited and can be selected appropriately according to the application. The thickness of the film-like or wiring-like metal layer is preferably 500 nm or less, more preferably 20 nm or less. There is no particular limitation on the lower limit, but it is preferably 1 nm or more.

[0290] [Semiconductor substrate processing methods]

[0291] Hereinafter, a semiconductor substrate, which is an example of the work to be processed in this processing method, and the processing method of applying this processing solution to the semiconductor substrate will be described in further detail.

[0292] This processing solution can be used in processing methods for semiconductor substrates that include a process of contacting the processing solution with a semiconductor substrate. It is particularly preferred for use in processing methods for semiconductor substrates having the aforementioned metal layer.

[0293] A semiconductor substrate may have a metal layer on only one side of its main surface, or it may have metal layers on both sides of its main surface. The metal layer may be disposed on the entire surface of the main surface of the semiconductor substrate, or it may be disposed on a portion of the main surface of the semiconductor substrate.

[0294] The metal layers of a semiconductor substrate are as described above. Furthermore, a semiconductor substrate may have two or more metal layers with different structures and / or compositions.

[0295] Furthermore, the term "semiconductor substrate" in this specification includes, for example, a semiconductor substrate composed of a single layer and a semiconductor substrate composed of multiple layers.

[0296] As a semiconductor substrate, for example, a semiconductor substrate having the aforementioned metal layer (preferably a cobalt-containing layer), barrier layer, and insulating layer on the surface of the wafer constituting the substrate can be cited.

[0297] There are no particular limitations on the types of semiconductor substrates. For example, various substrates can be listed, such as semiconductor wafers, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, FED (Field Emission Display) substrates, optical disc substrates, magnetic disk substrates, and optical disk substrates.

[0298] Examples of wafers constituting semiconductor substrates include silicon (Si) wafers, silicon carbide (SiC) wafers, silicon-containing resin wafers (glass epoxy wafers), gallium phosphide (GaP) wafers, gallium arsenide (GaAs) wafers, and indium phosphide (InP) wafers. Among these, silicon wafers, silicon carbide wafers, and silicon-containing resin wafers (glass epoxy wafers) are preferred.

[0299] Examples of silicon wafers include n-type silicon wafers doped with pentavalent atoms (e.g., phosphorus (P), arsenic (As), and antimony (Sb)) and p-type silicon wafers doped with trivalent atoms (e.g., boron (B) and gallium (Ga)). Examples of silicon wafers made of silicon include amorphous silicon, monocrystalline silicon, polycrystalline silicon, and polycrystalline silicon.

[0300] There are no particular restrictions on the size, thickness, shape, and layer structure of semiconductor substrates; they can be selected appropriately as needed.

[0301] There are no particular limitations on the barrier layer; for example, a barrier layer comprising one or more materials selected from Ta, tantalum nitride (TaN), Ti, titanium nitride (TiN), titanium tungsten (TiW), W, and tungsten nitride (WN) can be cited. Among these, Ta, TaN, Ti, or TiN are preferred.

[0302] There are no particular limitations on the insulating layer. For example, an insulating layer comprising one or more materials selected from silicon nitride (SiN), silicon oxide, silicon carbide (SiC), silicon carbonitride, silicon carbide oxide (SiOC), silicon oxynitride, and TEOS (tetraethoxysilane) can be cited. Among these, silicon nitride (SiN), TEOS, silicon carbide (SiC), or silicon carbide oxide (SiOC) are preferred. Furthermore, the insulating layer can be composed of multiple layers.

[0303] The semiconductor substrate may have a removal object that can be removed by a processing liquid.

[0304] In this specification, "on the semiconductor substrate" includes, for example, the surface and back surface, side surface, and groove of the semiconductor substrate. Furthermore, the object to be removed on the semiconductor substrate includes not only the case where the object to be removed is directly present on the surface of the semiconductor substrate, but also the case where the object to be removed is present on the semiconductor substrate through other layers.

[0305] In addition to the above, semiconductor substrates may also have various layers and / or structures as desired. For example, semiconductor substrates may have metal wiring, gate electrodes, source electrodes, drain electrodes, insulating layers, strongly magnetic layers, and / or non-magnetic layers, etc.

[0306] Semiconductor substrates may have exposed integrated circuit structures, such as interconnects of metal wiring and dielectric materials. Examples of metals and alloys used for the interconnects include aluminum, aluminum-copper alloys, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, and tungsten. The substrate may have layers of silicon oxide, silicon nitride, silicon carbide, and / or carbon-doped silicon oxide.

[0307] There are no particular limitations on the manufacturing method of semiconductor substrates. For example, by forming an insulating layer on the substrate, forming holes (or trenches) in the insulating layer, and sequentially forming a barrier layer and a metal layer on the insulating layer, and then performing planarization treatments such as chemical mechanical polishing (CMP), it is possible to manufacture a semiconductor substrate with an insulating layer, a barrier layer and a metal layer on the substrate.

[0308] There are no particular limitations on the methods for forming barrier layers and metal layers on insulating layers. Examples include sputtering, physical vapor deposition (PVD), atomic layer deposition (ALD), chemical vapor deposition (CVD), and molecular beam epitaxy (MBE).

[0309] Furthermore, the above method can also be performed through a specified mask to form a patterned metal layer on the substrate.

[0310] <Semiconductor substrate cleaning method>

[0311] As a preferred specific example of this processing method, a semiconductor substrate cleaning method can be described as a cleaning process in which the semiconductor substrate is cleaned by contacting the semiconductor substrate with the processing liquid.

[0312] In the semiconductor device manufacturing process, when a photoresist pattern is used as a mask to etch the metal layer and / or insulating layer of a semiconductor substrate using plasma etching, residues from the photoresist, metal layer, and insulating layer are generated on the semiconductor substrate. Furthermore, when unwanted photoresist patterns are removed by plasma ashing, residues from the ashed photoresist are generated on the semiconductor substrate.

[0313] The cleaning method for semiconductor substrates involves removing etching residues and ashing residues from the semiconductor substrate. This cleaning solution can be used as a cleaning solution in the aforementioned semiconductor substrate cleaning method. By using this cleaning solution, the aforementioned etching residues and / or ashing residues generated on the semiconductor substrate after etching can be removed, and the surface roughness of the metal layer (especially the cobalt-containing layer) of the semiconductor substrate can be further suppressed.

[0314] There are no particular limitations on the method of contacting the processing liquid with the semiconductor substrate. For example, well-known methods in the field of semiconductor device manufacturing can be appropriately adopted, such as immersion method in which the semiconductor substrate is immersed in the processing liquid, rotation (dropping) method in which the processing liquid is dripped while the semiconductor substrate is rotated, spray (spraying) method in which the processing liquid is sprayed, and brushing method in which the processing liquid is supplied to the semiconductor substrate while the cleaning component such as a brush is physically contacted with the surface of the semiconductor substrate to remove residues.

[0315] In the cleaning of semiconductor substrates, mechanical agitation methods can be used to further reduce impurities remaining on the surface of the semiconductor substrate and thereby further improve the cleaning ability of the processing solution. Examples of mechanical agitation methods include circulating the processing solution on the semiconductor substrate, flowing or spraying the processing solution over the semiconductor substrate, and agitating the processing solution with ultrasound or megasonic waves.

[0316] The above cleaning process can be performed once or more. When cleaning more than twice, the same method can be repeated or different methods can be combined.

[0317] The cleaning method for semiconductor substrates can be either a single-wafer method or a batch method.

[0318] Single-chip processing typically refers to processing one semiconductor substrate at a time, while batch processing typically refers to processing multiple semiconductor substrates simultaneously.

[0319] The temperature of the processing solution used for cleaning semiconductor substrates is not particularly limited as long as it is a temperature commonly used in this field. Cleaning is usually performed at room temperature (about 25°C), but the temperature can be arbitrarily selected to improve cleaning performance and suppress damage to the components. The preferred temperature of the processing solution is 10 to 60°C, and more preferably 15 to 50°C.

[0320] The cleaning time in the cleaning of semiconductor substrates can be appropriately varied depending on the type and content of the components contained in the treatment solution. In actual use, it is preferably 10 to 120 seconds, more preferably 20 to 90 seconds, and even more preferably 30 to 60 seconds.

[0321] The supply rate (supply speed) of the processing liquid when dripping or spraying the processing liquid onto the semiconductor substrate is preferably 50 to 5000 mL / min, more preferably 500 to 2000 mL / min.

[0322] (Rinsing process)

[0323] After the above cleaning process, a process of rinsing the semiconductor substrate with solvent can be performed (hereinafter also referred to as the "rinsing process").

[0324] The rinsing process is preferably performed continuously after the cleaning process described above, and involves rinsing the semiconductor substrate with a rinsing solution for 5 to 300 seconds. The rinsing process can be performed using the mechanical stirring method described above.

[0325] Examples of suitable rinsing solutions include, for example, water (preferably deionized (DI) water), methanol, ethanol, isopropanol, N-methylpyrrolidone, γ-butyrolactone, dimethyl sulfoxide, ethyl lactate, and propylene glycol monomethyl ether acetate. Furthermore, aqueous rinsing solutions with a pH greater than 8.0 (such as diluted aqueous ammonium hydroxide) can be used.

[0326] As a method for contacting the rinsing solution with the semiconductor substrate, the method for contacting the above-mentioned treatment solution with the semiconductor substrate can be applied in the same way.

[0327] (Drying process)

[0328] After the above cleaning or rinsing process, a drying process for the semiconductor substrate can be performed.

[0329] Examples of drying methods include rotary drying, methods of passing a drying gas over a semiconductor substrate, methods of heating a semiconductor substrate using a heating mechanism such as a heating plate or infrared lamp, marangoni drying, rotagoni drying, IPA (isopropyl alcohol) drying, and any combination thereof.

[0330] The drying time in the drying process depends on the specific method used, and is preferably 20 seconds to 5 minutes.

[0331] <Etching process of semiconductor substrates>

[0332] As another specific example of this processing method, an etching process can be described, in which a semiconductor substrate having a metal layer (especially a cobalt layer) is brought into contact with the processing solution to dissolve and remove the metal layer (especially the cobalt layer). That is, the processing solution can be used as an etching solution in an etching process to remove the metal layer on a semiconductor substrate.

[0333] As an etching process, for example, a method can be described by contacting a processing solution with a semiconductor substrate to dissolve and remove metal-containing substances on the semiconductor substrate. There are no particular limitations on the method of contacting the processing solution with the semiconductor substrate; any method described in semiconductor substrate cleaning methods can be applied.

[0334] As a further specific example of the above processing method, there is a semiconductor substrate processing method including a process P in which an oxidation treatment is performed on a semiconductor substrate containing a metal layer to oxidize the surface of the metal layer to form a metal oxide layer, and a process Q in which the surface of the metal oxide layer formed in the above process P is brought into contact with a processing liquid to dissolve the metal oxide layer.

[0335] Regarding the metal layer, including the preferred embodiment, it is the same as the metal layer possessed by the aforementioned workpiece.

[0336] The aforementioned metal oxide layer refers to the layer formed by oxidizing the surface of the aforementioned metal layer, also known as a type of metallic material. A portion of the surface of the metal layer can be a metal oxide layer, or the entire surface of the metal layer can be a metal oxide layer.

[0337] The metal oxide layer is an oxide of a metal monomer or alloy, preferably a layer composed of cobalt oxide, cobalt alloy oxide, ruthenium oxide, ruthenium alloy oxide, molybdenum oxide, molybdenum alloy oxide, aluminum oxide, aluminum alloy oxide, copper oxide or copper alloy oxide, more preferably a layer composed of cobalt oxide or cobalt alloy oxide, and even more preferably a layer composed of cobalt oxide.

[0338] The thickness of the metal oxide layer is, for example, 1 to 10 atomic layers. In addition, the thickness of 1 atomic layer of metal and metal oxide is less than 1 nm (for example, 0.3 nm to 0.4 nm).

[0339] Metal oxide layers are generally more soluble than metal layers in the processing solution (making them easier to etch). That is, the surface of the metal layer in process P is treated as a thin metal oxide layer, and in process Q, the processing solution is used to remove only the aforementioned metal oxide layer (and the portion of the metal layer below the metal oxide layer that can inevitably be dissolved), thereby removing (dissolving) only the extremely thin surface of the metal layer contained in the semiconductor substrate.

[0340] In addition, by alternately and repeatedly performing process P and process Q, the etching amount can be controlled with high precision.

[0341] As for the number of times each process is performed when alternating between process P and process Q, for example, combining process P and process Q into one cycle, 1 to 20 cycles are sufficient. From the viewpoint of excellent control of the amount of depression, the number of times each process is performed when alternating between process P and process Q is preferably 3 cycles or more, more preferably 5 cycles or more.

[0342] A semiconductor substrate may contain one type of metal layer or two or more types of metal layers. Furthermore, the semiconductor substrate may contain metallic materials other than metal layers or metal oxide layers, and some or all of these metallic materials may be intentionally or unavoidably removed during processes P and Q.

[0343] Process P is a process of oxidizing the surface of the metal layer on a semiconductor substrate containing the aforementioned metal layer to form a metal oxide layer.

[0344] There are no limitations on the method of oxidation treatment used to oxidize the surface of the metal layer to form a metal oxide layer. For example, liquid treatment in which an oxidizing liquid is brought into contact with the semiconductor substrate, gas treatment in which an oxidizing gas is brought into contact (ozone treatment in which ozone gas is brought into contact with the substrate described later, and oxygen heating treatment in which the gas is heated in an oxygen atmosphere, etc.), and plasma treatment using oxygen gas are all examples.

[0345] Oxidation treatment can be performed in one or more ways.

[0346] The oxidizing solution can be any solution capable of oxidizing the surface of the metal layer. Preferably, the oxidizing solution is a solution other than the one used in this treatment.

[0347] The preferred oxidizing solution is selected from water, hydrogen peroxide water, a mixed aqueous solution of ammonia and hydrogen peroxide (APM), a mixed aqueous solution of hydrofluoric acid and hydrogen peroxide water (FPM), a mixed aqueous solution of sulfuric acid and hydrogen peroxide water (SPM), a mixed aqueous solution of hydrochloric acid and hydrogen peroxide water (HPM), dissolved oxygen water, ozone dissolved water, perchloric acid, and nitric acid (hereinafter also referred to as "specific solutions").

[0348] The composition of hydrogen peroxide water, for example, the content of H2O2 relative to the total mass of hydrogen peroxide water is 0.5 to 31% by mass, more preferably 3 to 15% by mass.

[0349] The preferred composition of APM is, for example, within the range of "ammonia water: hydrogen peroxide water: water = 1:1:1" to "ammonia water: hydrogen peroxide water: water = 1:3:45" (mass ratio).

[0350] The preferred composition of FPM is, for example, within the range of "hydrofluoric acid:hydrogen peroxide water:water = 1:1:1" to "hydrofluoric acid:hydrogen peroxide water:water = 1:1:200" (mass ratio).

[0351] The preferred composition of SPM is, for example, within the range of "sulfuric acid:hydrogen peroxide water:water = 3:1:0" to "sulfuric acid:hydrogen peroxide water:water = 1:1:10" (mass ratio).

[0352] The preferred composition of HPM is, for example, within the range of "hydrochloric acid:hydrogen peroxide water:water = 1:1:1" to "hydrochloric acid:hydrogen peroxide water:water = 1:1:30" (mass ratio).

[0353] Furthermore, these preferred composition ratios refer to the composition ratios where ammonia water is 28% by mass, hydrofluoric acid is 49% by mass, sulfuric acid is 98% by mass, hydrochloric acid is 37% by mass, and hydrogen peroxide water is 30% by mass.

[0354] Furthermore, the volume ratio is based on the volume at room temperature.

[0355] Preferably, the description of the suitable range ["A:B:C=x:y:z"~"A:B:C=X:Y:Z"] shows at least one (preferably two, more preferably all) of the ranges ["A:B=x:y"~"A:B=X:Y"], ["B:C=y:z"~"B:C=Y:Z"] and ["A:C=x:z"~"A:C=X:Z"].

[0356] Dissolved oxygen water is, for example, an aqueous solution with an O2 content of 20 to 500 ppm by mass relative to the total mass of dissolved oxygen water.

[0357] Ozone-dissolved water is, for example, an aqueous solution in which the O3 content is 1 to 60 ppm by mass relative to the total mass of the ozone-dissolved water.

[0358] Perchloric acid, for example, is an aqueous solution containing 0.001 to 60% by mass of HClO4 relative to the total mass of the solution.

[0359] Nitric acid, for example, is an aqueous solution containing HNO3 at a concentration of 0.001 to 60% by mass relative to the total mass of the solution.

[0360] There are no particular limitations on the method of contacting the semiconductor substrate with the oxidizing solution (preferably a specific chemical solution). For example, methods such as immersing the semiconductor substrate in the oxidizing solution placed in a tank, spraying the oxidizing solution onto the semiconductor substrate, circulating the oxidizing solution onto the semiconductor substrate, and any combination thereof can be cited.

[0361] The contact time between the semiconductor substrate and the oxide solution is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes.

[0362] The temperature of the oxidizing solution is preferably 20–75°C, more preferably 20–60°C.

[0363] In gas processing, oxidizing gases that come into contact with the semiconductor substrate include, for example, dry air, oxygen, ozone gas, and mixtures thereof. The oxidizing gas may contain gases other than those mentioned above.

[0364] In gas processing, the oxidizing gas that comes into contact with the semiconductor substrate is preferably oxygen or ozone gas. When oxygen or ozone gas comes into contact with the semiconductor substrate, it is also preferable to have contact in an oxygen environment, an ozone environment, or a mixture of oxygen and ozone gas.

[0365] In gas processing, it is also preferable to heat the semiconductor substrate (e.g., at 40–200°C) while contacting it with an oxidizing gas.

[0366] Among them, the preferred gas treatment is ozone treatment, which involves contacting ozone gas with the semiconductor substrate, or oxygen heating treatment, which involves heating in an oxygen environment.

[0367] In the above-described ozone treatment, ozone gas can be brought into contact with the semiconductor substrate in an ozone environment, or in a mixed gas environment containing ozone gas and other gases (such as oxygen). Furthermore, the ozone treatment can be a process in which the semiconductor substrate is heated while the ozone gas is in contact with it.

[0368] Step Q is a process in which the semiconductor substrate obtained in step P is brought into contact with the processing solution to dissolve the metal oxide layer. There are no particular limitations on the method used to bring the semiconductor substrate into contact with the processing solution in step Q; examples similar to the method used to bring the semiconductor substrate into contact with the oxide solution can be given.

[0369] The contact time between the semiconductor substrate and the processing liquid is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes.

[0370] The temperature of the treatment solution is preferably 20–75°C, more preferably 20–60°C.

[0371] In process Q, the removal of the metal oxide layer can be carried out locally or as a whole.

[0372] In process Q, part or all of the metal layer may be intentionally or unavoidably removed (e.g., removing the metal oxide layer covering the surface and exposing the surface metal layer).

[0373] Pre-treating the processing solution provided to process Q by degassing can reduce the dissolved oxygen content. The metal layer exposed by removing the metal oxide layer through the processing solution is oxidized by the dissolved oxygen in the processing solution to become a new metal oxide layer. This new metal oxide layer is then removed by the processing solution. As a result, excessive removal of the metal layer can be suppressed by reducing the dissolved oxygen content of the processing solution.

[0374] For details regarding the specific method of using this processing solution to remove target substances such as metal inclusions on a semiconductor substrate, please refer to paragraphs

[0049] to

[0069] of International Publication No. 2019 / 138814, which are incorporated herein by reference.

[0375] This processing method can be implemented in combination before or after other processes in the manufacture of semiconductor devices. Other processes can be incorporated during the implementation of this processing method, and this processing method can also be incorporated during other processes.

[0376] Other processes include, for example, the formation processes of various structures such as metal wiring, gate structure, source structure, drain structure, insulating layer, strong magnetic layer and / or non-magnetic layer (layer formation, etching, CMP treatment and modification, etc.), resist formation process, exposure process and removal process, heat treatment process, cleaning process and inspection process, etc.

[0377] The above processing can be performed at any stage of the back end of the line (BEOL), middle end of the line (MOL), and front end of the line (FEOL).

[0378] Example

[0379] The present invention will now be described in further detail with reference to embodiments. The materials, amounts, proportions, processing contents, and processing steps shown in the following embodiments can be appropriately modified without departing from the spirit of the invention. Therefore, the scope of the present invention should not be interpreted limitedly by the embodiments shown below.

[0380] 〔raw material〕

[0381] The following ingredients were used as raw materials to prepare the treatment solutions for the examples and comparative examples.

[0382] In the preparation of the treatment solution, components classified as semiconductor grade or high-purity grade based on them were used.

[0383] The following shows the various components used as raw materials in the preparation of the treatment liquid.

[0384] <First ingredient>

[0385] • DBU: 1,8-diazabicyclo[5.4.0]undec-7-ene

[0386] DBN: 1,5-diazabicyclo[4.3.0]non-5-ene

[0387] <Second ingredient>

[0388] Compound A

[0389] [Chemical Formula 3]

[0390]

[0391] Compound B

[0392] [Chemical Formula 4]

[0393]

[0394] <Hydramine compounds (HA compounds)>

[0395] ·HA: Hydroxylamine

[0396] <Organic Solvents>

[0397] ·EGME: Ethylene glycol monomethyl ether

[0398] ·EGBE: Ethylene glycol monobutyl ether

[0399] MMB: 3-Methoxy-3-methyl-1-butanol

[0400] ·sulfolane

[0401] DEGEE: Diethylene glycol monoethyl ether

[0402] PG: Propylene Glycol

[0403] DEGBE: Diethylene glycol monobutyl ether

[0404] <Preservatives>

[0405] Tetrazole: Tetrazole

[0406] ·5M-BTA: 5-methyl-1H-benzotriazole (equivalent to the compound represented by formula (C)).

[0407] • BTA: Benzotriazole (equivalent to the compound represented by formula (C)).

[0408] ·123TZ: 1H-1,2,3-triazole (equivalent to the compound represented by formula (C))

[0409] ·124TZ: 1H-1,2,4-triazole

[0410] <Chlorinating Agent>

[0411] ·DHEG: N,N-bis(2-hydroxyethyl)glycine

[0412] DTPA (Diethylenetriaminepentaacetic acid)

[0413] ·EDTA: ethylenediaminetetraacetic acid

[0414] HIDA: Hydroxyethyliminodiacetic acid

[0415] • EDTMP: N,N,N',N'-ethylenediaminetetra(methylenephosphonic acid)

[0416] • NTMP: Nitrotrimethylenephosphonic acid (NTMP)

[0417] HEDP: 1-Hydroxyvinyl-1,1-diphosphonic acid

[0418] <Inorganic acids>

[0419] H3PO4: Phosphoric acid

[0420] <Water>

[0421] Ultrapure water

[0422] [Comparative Example 1]

[0423] The purified product, consisting of commercially available DBU, was dehydrated using a column method employing molecular sieve 3A (manufactured by FUJIFILM Wako Pure Chemical Corporation). Subsequently, the dehydrated purified product was sequentially purified by distillation, starting from the first tray distillation column, using a first tray distillation column (theoretical number of sections: 150) without a vacuum distillation mechanism connected in series with a second tray distillation column (theoretical number of sections: 150) equipped with a vacuum distillation mechanism.

[0424] Furthermore, a filtration device was used to perform cyclic filtration purification on the distilled purified substance. This filtration device includes: a flow path, in which the ion exchange resin and filter shown below are connected in series from upstream; and a return path, in which the purified substance is returned from the downstream end to the upstream end of the flow path. The number of cycles was set to 50.

[0425] The following details the components of the filtration device, starting from the upstream side.

[0426] • Anion exchange resin (the anion exchange resin described in manufacturing example 1 of paragraph 0028 of Japanese Patent Publication No. 2009-155208)

[0427] • Ion exchange filter (manufactured by Pall Corporation, IonKleen SL)

[0428] • Nylon filter (manufactured by Pall Corporation, Asymmetric, 5nm pore size)

[0429] • UPE filter (manufactured by INTEGRIS Products, Inc., for Purasol SP / SN solvent purification)

[0430] • PTFE filter (manufactured by Pall Corporation, XpressKLEEN, pore size 3nm)

[0431] • UPE filter (manufactured by INTEGRIS, Microgard, pore size 3nm)

[0432] In addition, in this type of cyclic filtration purification, the operation of passing the purified substance from the upstream purification unit to the downstream purification unit is counted as one cycle.

[0433] The composition of the purified product obtained in the above purification process was determined using GC-MS (manufactured by SHIMADZU CORPORATION, "GCMS-QP2020 NX"). For GC-MS determination, a diluent prepared by diluting the first component with methanol was used as the analyte, as needed.

[0434] Next, according to the composition described in Table 1, the purified product containing purified DBU, ultrapure water and chelating agent (NTMP) were mixed, and tetraethylammonium hydroxide (TEAH) was added to the mixture to adjust the pH to the value described in the “Processing Solution pH” column of Table 1, so as to prepare the processing solution of Comparative Example 1.

[0435] [Examples 1-29]

[0436] The purified product, which is a commercially available product and consists of the first component (DBN or DBU), was purified in the same manner as in Comparative Example 1. The composition of the purified product was then determined by GC-MS (manufactured by SHIMADZU CORPORATION, “GCMS-QP2020 NX”).

[0437] Next, according to the composition of each treatment solution recorded in Tables 1 and 2, the purified product containing the purified first component, ultrapure water, and other components other than the first component and water added as needed were mixed, and hydrochloric acid or tetraethylammonium hydroxide (TEAH) was added to the mixture to adjust the pH to the value recorded in the "Treatment Solution pH" column of Tables 1 and 2, thereby preparing the treatment solutions of each embodiment.

[0438] [evaluate]

[0439] <Co film roughness>

[0440] A silicon wafer (300 mm in diameter) with a cobalt-based metal film (wiring model, hereinafter also referred to as "Co film") on its surface was prepared. The Co film was 30 nm thick.

[0441] A wafer coated with a Co film was mounted in a rotary wafer processing apparatus (manufactured by Ekc Technologies, Inc.). The processing solutions of the examples and comparative examples were ejected from the surface of the mounted wafer at a flow rate of 1.5 L / min for 1 minute. Following this, the wafer was rinsed by spraying ultrapure water at a flow rate of 1 L / min onto its surface for 30 seconds, and then the wafer was rotary dried.

[0442] The surface roughness Ra of the Co film was measured using atomic force microscopy in an arbitrary area extending from the surface of the dried Co film to a 5 μm square region. The selected region was varied, and measurements were performed a total of three times. The surface roughness Ra of the Co film after each treatment solution was calculated by arithmetic averaging of the obtained values.

[0443] The surface roughness (Co film roughness) of the Co films treated with each treatment solution was evaluated based on the obtained surface roughness Ra of the Co films according to the following evaluation criteria. The results are shown in Tables 1 and 2.

[0444] (Co film roughness evaluation criteria)

[0445] “A”: The surface roughness Ra of the Co film is below 1.0 nm.

[0446] "B": The surface roughness Ra of the Co film is greater than 1.0 nm and less than 2.0 nm.

[0447] “C”: The surface roughness Ra of the Co film is greater than 2.0 nm and less than 3.0 nm.

[0448] “D”: The surface roughness Ra of the Co film exceeds 3.0 nm.

[0449] <Particle Defect Suppression>

[0450] A silicon wafer with a diameter of 300 mm was prepared, and the number and location of particulate foreign objects with a diameter of 28 nm or larger existing on the wafer surface were determined using the defect evaluation device "UVision8" (manufactured by Applied Materials, Inc.).

[0451] In a rotary wafer processing apparatus (manufactured by EKC Technology, Inc.), the wafer on which the foreign matter was measured was placed. The processing solutions of the examples and comparative examples were sprayed onto the surface of the placed wafer at a flow rate of 1.5 L / min for 1 minute. Next, after rinsing with ultrapure water sprayed onto the surface of the wafer at a flow rate of 1 L / min for 30 seconds, the wafer was rotary dried.

[0452] Using the aforementioned defect evaluation device, the number and location of granular foreign objects with a diameter of 28 nm or more on the surface of the obtained dried wafer were measured.

[0453] The number of particulate foreign particles with a diameter greater than 28 nm from the treatment solution was calculated by subtracting the number of particulate foreign particles measured before treatment from the number of particulate foreign particles measured after treatment (hereinafter also referred to as "particle defect number"). Based on the obtained particle defect number from the treatment solution, the particle defect suppression performance of each treatment solution was evaluated according to the following evaluation criteria. The results are shown in Tables 1 and 2.

[0454] (Evaluation criteria for particle defect suppression)

[0455] “S”: The number of particle defects from the treatment fluid is 0 or more and less than 100.

[0456] “A”: The number of particle defects from the treatment fluid is more than 100 and less than 500.

[0457] “B”: The number of particle defects from the processing fluid is more than 500 but less than 1000.

[0458] “C”: The number of particle defects from the processing fluid is more than 1,000.

[0459] Tables 1 and 2 below show the composition of the treatment solutions prepared in each embodiment and comparative example, as well as the evaluation results.

[0460] In the table, the "Content [mass%]" column indicates the content of the corresponding component (unit: mass%).

[0461] In the "Component 2" column, "A" and "B" refer to compound A and compound B mentioned above, respectively.

[0462] "HA compound" indicates hydroxylamine compound.

[0463]

[0464]

[0465] Based on the results in Tables 1 and 2, it was confirmed that the Co film of the treatment solution of the present invention has excellent surface roughness suppression properties.

[0466] Based on comparisons of Examples 1 to 5, it was confirmed that when the treatment solution contains a chelating agent, the suppression of particle defects is more excellent.

[0467] Based on comparisons of Examples 1 to 6 and Example 8, it was confirmed that when the treatment solution contains a preservative, the surface roughness suppression of the Co film is superior.

[0468] Based on comparisons of Examples 6, 7, and 19, it was confirmed that when the content of organic solvent is less than 20% by mass relative to the total mass of the treatment liquid, the surface roughness suppression of the Co film is superior.

Claims

1. A processing liquid for semiconductor devices, comprising: water; The first component is an alicyclic heterocyclic compound containing a nitrogen atom as a cyclizing atom; and The second component is a compound different from the first component and is an alicyclic heterocyclic compound having a hydroxyl group.

2. The treatment solution according to claim 1, wherein, The first component has two or more nitrogen atoms as cyclic atoms.

3. The treatment solution according to claim 1, wherein, The first component comprises at least one selected from 1,8-diazabicyclo[5.4.0]undec-7-ene and 1,5-diazabicyclo[4.3.0]non-5-ene.

4. The treatment solution according to claim 1, wherein, The second component contains nitrogen or oxygen atoms as cyclic atoms.

5. The treatment solution according to claim 1, wherein, The second component is a compound represented by formula (1) or a compound represented by formula (2) below. In formulas (1) and (2), X independently represents an oxygen atom, an imino atom, or an imino atom with a substituent, and n represents an integer from 1 to 3.

6. The treatment solution according to claim 1, wherein, The water content is 70% or more by mass relative to the total mass of the treatment liquid.

7. The treatment liquid according to claim 1, further comprising a chelating agent having a carboxylic acid group or a chelating agent having a phosphonic acid group.

8. The treatment liquid according to claim 1, further comprising an organic solvent.

9. The treatment solution according to claim 8, wherein, The organic solvent comprises at least one selected from glycol solvents, glycol ether solvents, amide solvents, alcohol solvents, and sulfoxide solvents.

10. The treatment liquid according to claim 1, further comprising a preservative.

11. The treatment liquid according to claim 10, wherein, The preservative comprises at least one compound selected from the following formula (A), the following formula (B), the following formula (C), and substituted or unsubstituted tetrazolium. In formula (A), R 1A ~R 5A Each of the following groups independently represents a hydrogen atom, a substituted or unsubstituted hydrocarbon group, a hydroxyl group, a carboxyl group, or a substituted or unsubstituted amino group, wherein the structure contains at least one group selected from hydroxyl, carboxyl, and substituted or unsubstituted amino groups. In equation (B), R 1B ~R 4B Each can be independently represented by a hydrogen atom or a substituted or unsubstituted hydrocarbon group. In equation (C), R 1C R 2C and R N Each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, and R 1C With R 2C They can be bonded arbitrarily to form a ring.

12. The treatment liquid according to claim 1, further comprising at least one hydroxylamine compound selected from hydroxylamine, hydroxylamine derivatives and their salts.

13. The treatment solution according to claim 1, further comprising an inorganic acid.

14. A method for treating a workpiece, comprising a step of contacting the workpiece having a cobalt-containing layer with a treatment liquid according to any one of claims 1 to 13.

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