Cleaning solution and semiconductor substrate cleaning method

Abstract

The present invention addresses the problem of providing a cleaning liquid for semiconductor devices, the cleaning liquid exhibiting excellent dissolution inhibition performance with respect to a metal layer that contains tungsten, while having excellent cleaning performance of dry etching residues. The present invention also addresses the problem of providing a method for cleaning a semiconductor substrate.　A cleaning liquid for semiconductor devices according to the present invention contains one or more hydroxylamine compounds that are selected from the group consisting of hydroxylamine and hydroxylamine salts, a component A that is represented by a specific formula (1), and water. With respect to this cleaning liquid for semiconductor devices, the mass ratio of the content of the hydroxylamine compounds to the content of the component A is from 5 to 200.

Description

[Technical Field]

[0001] The present invention relates to a cleaning solution and a method for cleaning a semiconductor substrate. [Background technology]

[0002] Semiconductor devices such as CCDs (Charge-Coupled Devices) and memories are manufactured by forming fine electronic circuit patterns on a substrate using photolithography technology. For example, semiconductor devices are manufactured by disposing a laminate on a substrate, the laminate including a metal layer serving as wiring material, an etching stop film, and an interlayer insulating film, forming a resist film on the laminate, and then performing a photolithography process and a dry etching process (e.g., plasma etching process). Specifically, in the photolithography process, the metal layer and / or the interlayer insulating film on the substrate is etched by dry etching using the obtained resist film as a mask. In this case, residues from the metal layer and / or the interlayer insulating film may adhere to the substrate, the metal layer and / or the interlayer insulating film, etc. In order to remove these adhered residues, cleaning using a processing liquid is often performed. In addition, the resist film used as a mask during etching is then removed from the laminate by a dry method (dry ashing) using ashing (ashing), a wet method, or the like. Residues derived from the resist film, etc., may adhere to the laminate from which the resist has been removed using the dry ashing method. In order to remove these adhered residues, cleaning using a treatment liquid is often performed. On the other hand, as a wet method for removing the resist film, there is an embodiment in which the resist film is removed using a treatment liquid. As described above, processing liquids are used in semiconductor device manufacturing processes to remove residues (etching residues and ashing residues) and / or resist films.

[0003] For example, Patent Document 1 discloses a cleaning solution for a substrate provided with a metal hard mask containing one or more specific metals, the cleaning solution containing at least one hydroxylamine compound selected from hydroxylamine and hydroxylamine salts, and water. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2017 / 099211 Summary of the Invention [Problem to be solved by the invention]

[0005] The present inventors have studied cleaning solutions for use in semiconductor devices with reference to the cleaning solution described in Patent Document 1, and have found that there is room for further improvement in the performance of inhibiting dissolution of metal layers containing tungsten, which are used as wiring materials and / or plug materials, and in the performance of cleaning dry etching residues.

[0006] Therefore, an object of the present invention is to provide a cleaning liquid for semiconductor devices that has excellent performance in inhibiting dissolution of metal layers containing tungsten and excellent performance in cleaning dry etching residues. Another object of the present invention is to provide a method for cleaning a semiconductor substrate. [Means for solving the problem]

[0007] As a result of extensive research into solving the above problems, the present inventors have found that the above problems can be solved by the following configuration.

[0008] [1] A cleaning solution for semiconductor devices, comprising at least one hydroxylamine compound selected from the group consisting of hydroxylamine and hydroxylamine salts, a component A represented by the formula (1) described below, and water, wherein the mass ratio of the content of the hydroxylamine compound to the content of the component A is 5 to 200. [2] The cleaning solution according to [1], further comprising alcohol. [3] The cleaning solution according to [2], wherein the alcohol includes a polyhydric alcohol having two or more hydroxy groups. [4] The cleaning solution according to [2] or [3], wherein the alcohol contains a compound represented by formula (2) described below. [5] The cleaning solution according to [4], wherein the alcohol contains two or more compounds represented by the formula (2) described below. [6] The cleaning solution according to any one of [2] to [5], wherein the alcohol comprises at least one selected from the group consisting of 1,3-propanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, glycerol, 2,4-pentanediol, 2,2-dimethyl-1,3-propanediol, and hexylene glycol. [7] The cleaning solution according to any one of [2] to [6], wherein the alcohol contains hexylene glycol. [8] The cleaning solution according to any one of [1] to [7], wherein the component A comprises at least one selected from the group consisting of 2-(2-aminoethylamino)ethanol, 2,2'-oxybis(ethylamine), and 2-(2-aminoethoxy)ethanol. [9] The cleaning liquid according to any one of [1] to [8], wherein the component A contains 2-(2-aminoethylamino)ethanol or 2,2'-oxybis(ethylamine).

[10] The cleaning solution according to any one of [1] to [9], wherein the content of the component A is 0.1 to 1 mass % relative to the total mass of the cleaning solution.

[11] The cleaning liquid according to any one of [1] to

[10] , further comprising an azole compound.

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

[11] , further comprising a quaternary ammonium hydroxide.

[13] The cleaning solution according to

[12] , wherein at least one of the four hydrocarbon groups substituted on the quaternary ammonium cation of the quaternary ammonium hydroxide is a hydrocarbon group having two or more carbon atoms.

[14] The cleaning solution according to any one of [1] to

[13] , further comprising a component B which is at least one selected from the group consisting of isobutene, (E)-2-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2,2,4-trimethyloxetane, 4-methyl-3-penten-2-ol, and 2,4,4,6-tetramethyl-1,3-dioxane, wherein when the composition contains one type of component B, the content of the component B relative to the total mass of the cleaning solution is 0.1 mass% or less, and when the composition contains two or more types of component B, the content of each of the components B relative to the total mass of the cleaning solution is 0.1 mass% or less.

[15] The cleaning solution according to any one of [1] to

[14] , further comprising at least one component C selected from the group consisting of ethylenediamine and 2-aminoethanol, wherein when the composition contains one type of component C, the content of component C relative to the total mass of the cleaning solution is 5.0 mass% or less, and when the composition contains two or more types of component C, the content of each of the components C relative to the total mass of the cleaning solution is 2.5 mass% or less.

[16] The cleaning solution according to any one of [1] to

[15] , which has a pH of 8 to 14 at 25°C.

[17] The cleaning solution according to any one of [1] to

[16] , which has a pH of 9 to 12 at 25°C.

[18] A method for cleaning a semiconductor substrate, comprising a cleaning step of cleaning a semiconductor substrate having a metal layer using the cleaning solution according to any one of [1] to

[17] .

[19] The method for cleaning a semiconductor substrate according to

[18] , wherein the metal layer contains tungsten, and the cleaning step removes dry etching residues adhering to the semiconductor substrate.

[20] The method for cleaning a semiconductor substrate according to

[18] or

[19] , wherein the semiconductor substrate has a layer containing cobalt or titanium nitride, and the cleaning step removes dry etching residues adhering to the semiconductor substrate.

[21] The method for cleaning a semiconductor substrate according to any one of

[18] to

[20] , wherein the semiconductor substrate has an etching stop layer made of aluminum oxide, and at least a portion of the etching stop layer is removed by the cleaning step. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a cleaning liquid for semiconductor devices that has excellent performance in inhibiting dissolution of a metal layer containing tungsten and excellent performance in cleaning dry etching residues. The present invention also provides a method for cleaning a semiconductor substrate. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view showing an example of a laminate that is an object to be cleaned in a method for cleaning a semiconductor substrate. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below. The following description of the components may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In this specification, the term "preparation" includes not only synthesizing or compounding specific materials, but also procuring predetermined items by purchasing or the like. In this specification, when two or more types of a component are present, the "content" of that component means the total content of those two or more components.

[0012] In this specification, "ppm" stands for "parts-per-million (10 -6 )" "ppb" is "parts-per-billion(10 -9 ) and "ppt" stands for "parts-per-trillion (10 -12 )" In this specification, 1 Å (angstrom) corresponds to 0.1 nm. In the description of groups (atomic groups) in this specification, when a notation does not specify whether they are substituted or unsubstituted, it encompasses both unsubstituted and substituted groups, as long as it does not impair the effects of the present invention. For example, the term "hydrocarbon group" encompasses not only hydrocarbon groups without substituents (unsubstituted hydrocarbon groups), but also hydrocarbon groups with substituents (substituted hydrocarbon groups). This also applies to each compound. As used herein, "light" refers to actinic rays or radiation. Furthermore, as used herein, "radiation" refers to, for example, the bright line spectrum of a mercury lamp, far ultraviolet light typified by an excimer laser, extreme ultraviolet light (EUV light), X-rays, or electron beams. Unless otherwise specified, as used herein, "exposure" includes not only exposure with a mercury lamp, far ultraviolet light typified by an excimer laser, X-rays, or EUV light, but also drawing with particle beams such as electron beams or ion beams.

[0013] [Cleaning solution] The cleaning solution of the present invention (hereinafter also referred to as "the present cleaning solution") contains one or more hydroxylamine compounds selected from the group consisting of hydroxylamine and hydroxylamine salts, component A represented by formula (1) described below, and water, and the mass ratio of the content of the hydroxylamine compound to the content of component A is 5 to 200. The present inventors have found that when a cleaning solution contains the above-mentioned combination of components, the cleaning solution has excellent performance in inhibiting dissolution of a metal layer containing tungsten and excellent performance in cleaning dry etching residues, and have completed the present invention. Hereinafter, when a cleaning solution or cleaning method has excellent performance in inhibiting dissolution of a metal layer containing tungsten (W-containing layer) or excellent performance in cleaning dry etching residues, it is also referred to as "having excellent effects of the present invention."

[0014] Each component contained in this cleaning solution will be described below.

[0015] [Hydroxylamine Compounds] The cleaning solution includes a hydroxylamine compound, which is at least one selected from the group consisting of hydroxylamine and hydroxylamine salts. In this specification, "hydroxylamine" means unsubstituted hydroxylamine (NH2OH).

[0016] The hydroxylamine salt may be an inorganic acid salt or an organic acid salt, preferably an inorganic acid salt formed by bonding a nonmetallic atom such as Cl, S, N, or P with a hydrogen atom, more preferably a salt of an acid such as hydrochloric acid, sulfuric acid, or nitric acid. Specific examples of the inorganic acid salt of hydroxylamine include hydroxylamine nitrate, hydroxylamine sulfate, hydroxylamine hydrochloride, and hydroxylamine phosphate, as well as mixtures thereof. Organic acid salts of hydroxylamine may also be used, such as hydroxylammonium citrate, hydroxylammonium oxalate, and hydroxylammonium fluoride. As the hydroxylamine compound, hydroxylamine or hydroxylamine sulfate is preferred, and hydroxylamine is more preferred, in terms of achieving better effects of the present invention.

[0017] The hydroxylamine compounds may be used alone or in combination of two or more. The content of the hydroxylamine compound is, for example, 0.1 to 30% by mass relative to the total mass of the cleaning liquid, and in terms of better effects of the present invention, it is preferably 0.3 to 20% by mass, more preferably 1 to 15% by mass.

[0018] [Component A] The cleaning solution contains a component A represented by the following formula (1). NH2-CH2CH2-X-CH2CH2-Y (1) In formula (1), X represents -NR- or -O-, R represents a hydrogen atom or a substituent, and Y represents a hydroxy group (-OH) or a primary amino group (-NH2).

[0019] Examples of the substituent represented by R include substituted or unsubstituted hydrocarbon groups, and substituted or unsubstituted alkyl groups are preferred. The hydrocarbon groups and alkyl groups may be linear, branched, or cyclic. The number of carbon atoms in the hydrocarbon groups and alkyl groups is, for example, 1 to 6, preferably 1 to 3, and more preferably 1 or 2. Examples of the substituent that the hydrocarbon groups and alkyl groups may have include a hydroxy group and a primary amino group. R is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms which may have a hydroxy group or a primary amino group, more preferably a hydrogen atom or an ethyl group which may have a hydroxy group or a primary amino group, and even more preferably a hydrogen atom.

[0020] The number of amino groups that Component A has is, for example, 1 to 5, preferably 1 to 3, more preferably 1 or 2, and even more preferably 2. The number of hydroxy groups that Component A has is, for example, 0 to 4, preferably 0 to 2, and more preferably 1 or 2. The total number of amino groups and hydroxy groups that Component A has is, for example, 3 to 5, preferably 3 or 4, and more preferably 3.

[0021] Examples of component A include 2-(2-aminoethoxy)ethanol, 2-(2-aminoethylamino)ethanol, 2,2′-oxybis(ethylamine), diethylenetriamine, N,N-bis(2-hydroxyethyl)ethylenediamine, 2-[bis(2-aminoethyl)amino]ethanol, N-methyl-N-(2-hydroxyethyl)ethylenediamine, and N-ethyl-N-(2-hydroxyethyl)ethylenediamine. Of these, 2-(2-aminoethoxy)ethanol, 2-(2-aminoethylamino)ethanol, 2,2'-oxybis(ethylamine), or diethylenetriamine is preferred, 2-(2-aminoethoxy)ethanol, 2-(2-aminoethylamino)ethanol, or 2,2'-oxybis(ethylamine) is more preferred, and 2-(2-aminoethylamino)ethanol or 2,2'-oxybis(ethylamine) is even more preferred.

[0022] Component A may be used alone or in combination of two or more. The content of component A is preferably from 0.01 to 10% by mass, more preferably from 0.03 to 5% by mass, and even more preferably from 0.1 to 1% by mass, based on the total mass of the cleaning liquid.

[0023] In this cleaning solution, the mass ratio of the content of the hydroxylamine compound to the content of component A (content of hydroxylamine compound / content of component A) is 5 to 200. Although the detailed mechanism is unknown, by having the content ratio of the hydroxylamine compound to component A within the above range, it is possible to further improve the dissolution suppression performance for W-containing layers while maintaining excellent performance in cleaning dry etching residues. From the above viewpoints, the mass ratio of the content of the hydroxylamine compound to the content of component A (content of the hydroxylamine compound / content of component A) is preferably 3-100, and more preferably 5-60.

[0024] 〔water〕 The cleaning solution contains water. The water is not particularly limited, and distilled water, deionized water, and pure water (ultrapure water) can be used. Pure water is preferred because it contains almost no impurities and has less effect on the semiconductor substrate during the manufacturing process of the semiconductor substrate. Deionized water (DIW) containing reduced inorganic anions and metal ions is preferred as the pure water, and DIW containing reduced concentrations of ions derived from metal atoms such as Fe, Co, Na, K, Ca, Cu, Mg, Mn, Li, Al, Cr, Ni, and Zn is more preferred. In particular, when used to prepare a cleaning solution, the concentration of ions derived from metal atoms in the water is preferably on the order of ppt or less (in one embodiment, the metal content is less than 0.001 ppt by mass). The content of inorganic anions and metal ions is preferably adjusted by purification using a filtration membrane or ion exchange membrane, or by distillation. Examples of adjustment methods include those described in paragraphs

[0074] to

[0084] of JP 2011-110515 A and those described in JP 2007-254168 A.

[0025] The water content is not particularly limited, but is, for example, 1 to 95 mass %, preferably 10 to 90 mass %, and more preferably 30 to 85 mass %, relative to the total mass of the cleaning liquid.

[0026] The water used in the embodiment of the present invention is preferably the water prepared as described above. The water is preferably used not only as a cleaning solution but also for cleaning a container, and is preferably used in the manufacturing process of the cleaning solution, in measuring the components of the cleaning solution, and in measurements for evaluating the cleaning solution.

[0027] [Optional ingredients] The cleaning solution may further contain components other than those described above. Optional components that the cleaning solution may contain are described below.

[0028] <Alcohol> The cleaning solution preferably contains alcohol. In this specification, the term "alcohol" refers to a compound having at least one hydroxy group, which is not included in Component A, the azole compounds described below, and the alkanolamines described below.

[0029] Examples of alcohols include compounds having a main chain skeleton containing a linear or cyclic aliphatic hydrocarbon group and at least one hydroxy group bonded to the main chain skeleton. In the main chain skeleton of the alcohol, one or more methanediyl groups (-CH-) constituting the linear or cyclic aliphatic hydrocarbon group may be substituted with a heteroatom. Examples of heteroatoms include -O- and -S-.

[0030] There is no particular limitation on the number of hydroxy groups (alcoholic hydroxy groups) that the alcohol has. That is, the alcohol may be a monoalcohol having one hydroxy group, or a polyhydric alcohol having two or more hydroxy groups. As the alcohol, a polyhydric alcohol is preferred because it has better dissolution-inhibiting properties for the metal layer (particularly the TiN-containing layer), and among these, a polyhydric alcohol having two or three hydroxy groups is more preferred, and a polyhydric alcohol having two hydroxy groups is even more preferred. The number of carbon atoms in the alcohol is not particularly limited, but is preferably 1 to 10, more preferably 2 to 8, and even more preferably 3 to 6.

[0031] A preferred polyhydric alcohol is a compound represented by the following formula (2). HO-C(R 1 )2-C(R 2 )2-C(R 3 )2-OH (2) In formula (2), R 1 , R 2 and R 3 represents a hydrogen atom, a hydroxy group, or an alkyl group which may have a hydroxy group. 1 , multiple R 2 and multiple R 3 may be the same or different from each other.

[0032] R 1 and R 3 is preferably a hydrogen atom, a hydroxy group, or an unsubstituted alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R 2 is preferably a hydrogen atom, a hydroxy group, or an unsubstituted alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a hydroxy group, or a methyl group, and even more preferably a hydrogen atom or a methyl group. R in Equation (2) 1 , R 2 and R 3 A preferred combination is one in which 1 to 3 are unsubstituted alkyl groups having 1 to 3 carbon atoms (more preferably methyl groups), 0 or 1 are hydroxy groups, and the remainder are hydrogen atoms.

[0033] Specific examples of compounds contained in alcohol are shown below. Among polyhydric alcohols, examples of the compound represented by the above formula (2) include 1,3-propanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 2,4-pentanediol, 2,2-dimethyl-1,3-propanediol, hexylene glycol (2-methyl-2,4-pentanediol), and glycerol. Examples of polyhydric alcohols other than the compound represented by formula (2) above include ethylene glycol, propylene glycol, 1,4-butanediol, 1,2-butanediol, 2,3-butanediol, pinacol, 1,3-cyclopentanediol, diethylene glycol, triethylene glycol, and tetraethylene glycol.

[0034] Examples of monoalcohols include monoalcohols whose main chain structure consists of an aliphatic hydrocarbon group, such as methanol, ethanol, 1-propanol, 2-propanol (isopropanol), 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 2-pentanol, t-pentyl alcohol, 1-hexanol, allyl alcohol, propargyl alcohol, 2-butenyl alcohol, 3-butenyl alcohol, 4-penten-2-ol, cyclopentanol, cyclohexanol, and tetrahydrofurfuryl alcohol, as well as ethylene glycol monoalkyl ethers. Examples of such monoalcohols include those having an ether group (—O—) in the main chain structure, such as ethylene glycol monoalkyl ethers (for example, 2-ethoxyethanol), diethylene glycol monoalkyl ethers, triethylene glycol monoalkyl ethers, 1-methoxy-2-propanol, 2-methoxy-1-propanol, 1-ethoxy-2-propanol, 2-ethoxy-1-propanol, propylene glycol mono-n-propyl ether, dipropylene glycol monoalkyl ethers, tripropylene glycol monoalkyl ethers, ethylene glycol monobenzyl ether, and diethylene glycol monobenzyl ether.

[0035] As the alcohol, 1,3-propanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, glycerol, 2,4-pentanediol, 2,2-dimethyl-1,3-propanediol, or hexylene glycol is more preferable, 1,3-butanediol, 2,4-pentanediol, or hexylene glycol is particularly preferable, and hexylene glycol is most preferable in terms of achieving better effects of the present invention.

[0036] The alcohol may be used alone or in combination of two or more. In terms of achieving better effects of the present invention, the cleaning liquid preferably contains two or more compounds represented by the above formula (2). The content of the alcohol is not particularly limited, and is, for example, 1 to 90 mass % relative to the total mass of the cleaning liquid, preferably 3 to 80 mass %, and more preferably 4 to 70 mass %.

[0037] <Azole compounds> The cleaning solution may contain an azole compound. An azole compound is a compound that contains at least one nitrogen atom and has an aromatic five-membered hetero ring. The number of nitrogen atoms contained in the five-membered hetero ring of the azole compound is not particularly limited, and is preferably 1 to 4, and more preferably 2 to 4.

[0038] The azole compound may have a substituent on the five-membered heterocyclic ring. Examples of such a substituent include a hydroxy group, a carboxy group, a mercapto group, an amino group, and a substituted or unsubstituted hydrocarbon group. When two substituents are adjacent to each other on the five-membered heterocyclic ring, the two substituents may be bonded to each other to form a ring. Examples of the hydrocarbon group that the five-membered heterocyclic ring has as a substituent include an alkyl group (preferably having 1 to 12 carbon atoms, and more preferably having 1 to 6 carbon atoms), an alkenyl group (preferably having 2 to 12 carbon atoms, and more preferably having 2 to 6 carbon atoms), an alkynyl group (preferably having 2 to 12 carbon atoms, and more preferably having 2 to 6 carbon atoms), an aryl group (preferably having 6 to 18 carbon atoms, and more preferably having 6 to 10 carbon atoms), and an aralkyl group (preferably having 7 to 23 carbon atoms, and more preferably having 7 to 11 carbon atoms). Examples of the substituents that the hydrocarbon groups have include a hydroxy group, a carboxy group, and —N(R a )(R b ) are listed. R a and R b each independently represents a hydrogen atom, an alkyl group (preferably having 1 to 6 carbon atoms, more preferably having 1 to 4 carbon atoms), or a hydroxyalkyl group (preferably having 1 to 6 carbon atoms, more preferably having 1 to 4 carbon atoms).

[0039] The ring formed by bonding two adjacent substituents on the five-membered heterocyclic ring is not particularly limited, but is preferably an aromatic ring (either monocyclic or polycyclic), more preferably a benzene ring. The ring formed by bonding two of the above-mentioned substituents may have a substituent. The substituent is not particularly limited, but examples thereof include those exemplified as the substituents of the hydrocarbon group of the five-membered heterocyclic ring.

[0040] Examples of azole compounds include imidazole compounds in which one of the atoms constituting the azole ring is a nitrogen atom, pyrazole compounds in which two of the atoms constituting the azole ring are nitrogen atoms, thiazole compounds in which one of the atoms constituting the azole ring is a nitrogen atom and the other is a sulfur atom, triazole compounds in which three of the atoms constituting the azole ring are nitrogen atoms, and tetrazole compounds in which four of the atoms constituting the azole ring are nitrogen atoms.

[0041] Examples of imidazole compounds include imidazole, 1-methylimidazole, 2-methylimidazole, 5-methylimidazole, 1,2-dimethylimidazole, 2-mercaptoimidazole, 4,5-dimethyl-2-mercaptoimidazole, 4-hydroxyimidazole, 2,2'-biimidazole, 4-imidazolecarboxylic acid, histamine, and benzimidazole.

[0042] Examples of pyrazole compounds include pyrazole, 4-pyrazolecarboxylic acid, 1-methylpyrazole, 3-methylpyrazole, 3-amino-5-hydroxypyrazole, 3-aminopyrazole, and 4-aminopyrazole.

[0043] Examples of thiazole compounds include 2,4-dimethylthiazole, benzothiazole, and 2-mercaptobenzothiazole.

[0044] Examples of triazole compounds include compounds having a benzotriazole skeleton in which two adjacent substituents on a triazole ring are bonded to each other to form a benzene ring. Examples of compounds having a benzotriazole skeleton include 1H-benzotriazole, 2H-benzotriazole, and compounds in which the benzene ring and / or triazole ring of 1H-benzotriazole or 2H-benzotriazole is substituted with at least one substituent selected from the group consisting of an alkyl group (preferably an alkyl group having 1 to 8 carbon atoms), an amino group, a hydroxy group, a carboxy group, a halogen atom, an aryl group, and groups formed by combining these. More specifically, 1H-benzotriazole, 2H-benzotriazole, 5-methyl-1H-benzotriazole (CAS Registry Number: 136-85-6), tolyltriazole (CAS Registry Number: 29385-43-1), 5-aminobenzotriazole, 1-hydroxybenzotriazole, carboxybenzotriazole (e.g., benzotriazole-5-carboxylic acid and 4-carboxybenzotriazole), 5,6-dimethylbenzotriazole, 1-[N,N-bis(hydroxyethyl)aminoethyl]benzotriazole, 1-(1,2-dicarboxyethyl)benzotriazole, 1-[N,N-bis(2-ethylhexyl)aminomethyl]benzotriazole, 1-[N,N-bis(2-ethylhexyl)aminomethyl]methylbenzotriazole, and 2,2'-{[(4-methyl-1H-benzotriazol-1-yl)methyl]imino}bisethanol (trade name "IRGAMET" 42" manufactured by BASF). Examples of triazole compounds other than compounds having a benzotriazole skeleton include 1,2,4-triazole, 3-methyl-1,2,4-triazole, 3-amino-1,2,4-triazole, 1,2,3-triazole, and 1-methyl-1,2,3-triazole.

[0045] Examples of the tetrazole compound include unsubstituted tetrazole and tetrazole having a hydroxy group, a carboxy group, or a substituted or unsubstituted amino group as a substituent. When the amino group is substituted, the substituent is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms. More specific examples of tetrazole compounds include 1H-tetrazole (1,2,3,4-tetrazole), 5-methyl-1H-tetrazole, 5-amino-1H-tetrazole, 1,5-pentamethylenetetrazole, 1-phenyl-5-mercaptotetrazole, and 1-(2-dimethylaminoethyl)-5-mercaptotetrazole.

[0046] The azole compound is preferably a triazole compound or a tetrazole compound, more preferably at least one selected from the group consisting of 1,2,4-triazole, 1,2,3-triazole, 1H-tetrazole, 5-aminotetrazole, 1H-benzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, carboxybenzotriazole, and 2,2'-[{(4-methyl-1H-benzotriazol-1-yl)methyl}imino]bisethanol, and even more preferably 1H-tetrazole, 1H-benzotriazole, tolyltriazole, 5-methyltriazole, or 2,2'-[{(4-methyl-1H-benzotriazol-1-yl)methyl}imino]bisethanol. In this specification, the above azole compounds include their tautomers.

[0047] The azole compounds may be used alone or in combination of two or more. The content of the azole compound is preferably from 0.01 to 10% by mass, more preferably from 0.05 to 5% by mass, and even more preferably from 0.1 to 3% by mass, based on the total mass of the cleaning liquid.

[0048] <Basic compounds> The cleaning liquid may contain a basic compound. The basic compound is intended to mean a compound that, when dissolved in water, causes the solution to have a pH of more than 7. The basic compound functions as a pH adjuster that adjusts the pH of the cleaning solution.

[0049] The basic compound is not particularly limited, and examples thereof include quaternary ammonium compounds, ammonium hydroxide, and amine compounds (excluding compounds included in the above component A and the above azole compounds).

[0050] (Quaternary ammonium compounds) The cleaning solution may contain a quaternary ammonium compound, which is a compound having one quaternary ammonium cation in the molecule or a salt thereof. The quaternary ammonium compound is not particularly limited as long as it is a compound having one quaternary ammonium cation in which four hydrocarbon groups (preferably alkyl groups) are substituted on a nitrogen atom, or a salt thereof. Examples of quaternary ammonium compounds include quaternary ammonium hydroxides, quaternary ammonium fluorides, quaternary ammonium bromides, quaternary ammonium iodides, quaternary ammonium acetates, and quaternary ammonium carbonates.

[0051] Among these, the cleaning liquid preferably contains a quaternary ammonium hydroxide, and more preferably a compound represented by the following formula (a1), in terms of achieving better effects of the present invention.

[0052] [ka]

[0053] In the above formula (a1), R a1 ~R a4 R each independently represents an alkyl group having 1 to 16 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aralkyl group having 7 to 16 carbon atoms, or a hydroxyalkyl group having 1 to 16 carbon atoms. a1 ~R a4 At least two of these may be bonded to each other to form a cyclic structure. The alkyl group may be straight-chain, branched-chain, or cyclic.

[0054] In terms of superior Co corrosion prevention, it is preferable that at least one of the four hydrocarbon groups substituted on the quaternary ammonium cation is a hydrocarbon group having two or more carbon atoms as the quaternary ammonium hydroxide. That is, R in the above formula (a1) a1 ~R a4 each independently represents an alkyl group having 2 to 16 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aralkyl group having 7 to 16 carbon atoms, or a hydroxyalkyl group having 1 to 16 carbon atoms, or R a1 ~R a4 It is preferred that at least two of the groups be bonded to each other to form a cyclic structure.

[0055] Examples of the compound represented by the above formula (a1) include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide, tetrabutylammonium hydroxide (TBAH), methyltripropylammonium hydroxide, methyltributylammonium hydroxide, ethyltrimethylammonium hydroxide, methyltriethylammonium hydroxide, dimethyldiethylammonium hydroxide, benzyltrimethylammonium hydroxide (BzTMAH), hexadecyltrimethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide, and spiro-(1,1')-bipyrrolidinium hydroxide. Among these, TEAH, tetrapropylammonium hydroxide, TBAH, methyltripropylammonium hydroxide, methyltributylammonium hydroxide, ethyltrimethylammonium hydroxide, dimethyldiethylammonium hydroxide, BzTMAH, hexadecyltrimethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide, or spiro-(1,1')-bipyrrolidinium hydroxide is preferred.

[0056] The quaternary ammonium compounds may be used alone or in combination of two or more. When the cleaning liquid contains a quaternary ammonium compound, the content thereof is preferably 0.01 to 30 mass %, more preferably 0.1 to 20 mass %, based on the total mass of the cleaning liquid.

[0057] (Ammonium hydroxide) The cleaning solution may contain ammonium hydroxide (NH4OH) as a basic compound. When the cleaning liquid contains ammonium hydroxide, its content is not particularly limited, but is preferably 0.01 to 10 mass %, more preferably 0.05 to 5.0 mass %, relative to the total mass of the cleaning liquid.

[0058] (amine compounds) In this specification, the term "amine compound" refers to a compound having an amino group in the molecule, which is not included in either the above-mentioned component A or azole compounds. Examples of amine compounds 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 salts thereof. Examples of salts of amine compounds include salts with inorganic acids in which at least one nonmetal selected from the group consisting of Cl, S, N, and P is bonded to hydrogen, and hydrochlorides, sulfates, or nitrates are preferred. The amine compound is preferably a water-soluble amine that can dissolve 50 g or more in 1 L of water. Examples of the amine compound include alicyclic amine compounds, alkanolamines other than component A, and amine compounds other than these compounds.

[0059] The alicyclic amine compound refers to an amine compound having an alicyclic (non-aromatic ring) structure in the molecule. Examples of alicyclic amine compounds include 1,8-diazabicyclo[5.4.0]-7-undecene (DBU), ε-caprolactam, Compound 1 below, Compound 2 below, Compound 3 below, 1,4-diazabicyclo[2.2.2]octane (DABCO), tetrahydrofurfurylamine, N-(2-aminoethyl)piperazine, hydroxyethylpiperazine, piperazine, 2-methylpiperazine, trans-2,5-dimethylpiperazine, cis-2,6-dimethylpiperazine, 2-piperidinemethanol, cyclohexylamine, and 1,5-diazabicyclo[4.3,0]-5-nonene.

[0060] [ka]

[0061] Alkanolamines are amine compounds other than component A that have at least one amino group and at least one hydroxy group (preferably a hydroxyl alkyl group) in the molecule. Hereinafter, the mere expression "alkanolamine" is intended to refer to an alkanolamine that does not fall under Component A.

[0062] Examples of alkanolamines include compounds having a main chain skeleton consisting of a chain-like aliphatic hydrocarbon group, at least one amino group bonded to the main chain skeleton, and at least one alcoholic hydroxyl group bonded to the main chain skeleton. In addition, in the main chain skeleton, one or more methanediyl groups (-CH2-) constituting the chain-like aliphatic hydrocarbon group may be substituted with a heteroatom. Examples of heteroatoms include -O-, -S-, and -NH-, and -O- or -NH- is preferred.

[0063] The number of amino groups that the alkanolamine has is, for example, 1 to 5, preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. The amino group contained in the alkanolamine may be any of a primary amino group (-NH), a secondary amino group (>NH), and a tertiary amino group (>N-). However, the alkanolamine preferably has at least one selected from the group consisting of a primary amino group and a secondary amino group, and more preferably, all of the amino groups contained in the alkanolamine are primary amino groups or secondary amino groups. The number of hydroxy groups that the amino alcohol has is, for example, 1 to 5, preferably 1 to 3, and more preferably 1 or 2.

[0064] Examples of alkanolamines include 2-aminoethanol, diethanolamine (DEA), triethanolamine (TEA), trishydroxymethylaminomethane (Tris), N,N-dimethylethanolamine, N,N-diethylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-methylethanolamine, 2-amino-2-methyl-1-propanol, 2-amino-2-methyl-1,3-dipropanol, 2-amino-2-ethyl-1,3-dipropanol, and 2-(methylamino)-2-methyl-1-propanol.

[0065] Among the amine compounds, primary amines other than Component A, alicyclic amine compounds, and alkanolamines include, for example, methylamine, ethylamine, ethylenediamine, propylamine, propylenediamine, butylamine, pentylamine, methoxyethylamine, and methoxypropylamine. Examples of the secondary amine other than Component A, the alicyclic amine compound, and the alkanolamine include dimethylamine, diethylamine, dipropylamine, and dibutylamine (DBA). Examples of tertiary amines other than component A, alicyclic amine compounds, and alkanolamines include trimethylamine, triethylamine, and tributylamine (TBA).

[0066] -Component C- The cleaning liquid preferably contains component C, which is at least one selected from the group consisting of ethylenediamine and 2-aminoethanol, in that the effects of the present invention are more excellent. The content of component C in the cleaning solution is not particularly limited, but when the cleaning solution contains one type of component C, it is preferably 20 mass% or less, more preferably 5 mass% or less, relative to the total mass of the cleaning solution. The lower limit is not particularly limited, but it is preferably 0.00001 mass% or more, more preferably 0.001 mass% or more, relative to the total mass of the cleaning solution. When the cleaning solution contains two or more kinds of component C, the content of each component C relative to the total mass of the cleaning solution is preferably 10 mass% or less, more preferably 2.5 mass% or less. Although there is no particular lower limit, the content of each component C relative to the total mass of the cleaning solution is preferably 0.00001 mass% or more, more preferably 0.001 mass% or more.

[0067] Component C may be either ethylenediamine or 2-aminoethanol, or a combination of both. The total content of component C in the cleaning liquid is not particularly limited, but is preferably from 0.0001 to 20% by mass, and more preferably from 0.001 to 5% by mass.

[0068] The amine compounds may be used alone or in combination of two or more. When the cleaning liquid contains an amine compound, its content is not particularly limited, but is preferably 0.01 to 30 mass %, more preferably 0.1 to 20 mass %, based on the total mass of the cleaning liquid.

[0069] The basic compounds may be used singly or in combination of two or more. When the cleaning liquid contains a basic compound, the content thereof is preferably from 0.01 to 30% by mass, more preferably from 0.1 to 20% by mass, based on the total mass of the cleaning liquid.

[0070] <Acidic compounds> The cleaning solution may contain an acidic compound as a pH adjuster. The acidic compound may be an inorganic acid or an organic acid (excluding the chelating agents described below). Examples of inorganic acids include sulfuric acid, hydrochloric acid, acetic acid, nitric acid, and phosphoric acid, with sulfuric acid, hydrochloric acid, and acetic acid being preferred. Examples of organic acids include lower (C1-C4) aliphatic monocarboxylic acids such as formic acid, acetic acid, propionic acid, and butyric acid. In addition, the chelating agent described below may also function as the acidic compound.

[0071] The acidic compounds may be used singly or in combination of two or more. The type and content of the acidic compound may be appropriately selected and adjusted so that the pH of the cleaning solution falls within the range described below.

[0072] <Component B> In terms of achieving better effects of the present invention, the cleaning liquid preferably contains Component B, which is at least one selected from the group consisting of isobutene, (E)-2-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2,2,4-trimethyloxetane, 4-methyl-3-penten-2-ol, and 2,4,4,6-tetramethyl-1,3-dioxane. As component B, at least one selected from the group consisting of (E)-2-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2,2,4-trimethyloxetane, 4-methyl-3-penten-2-ol, and 2,4,4,6-tetramethyl-1,3-dioxane is preferred, as this will further enhance the effects of the present invention.

[0073] The content of component B in the cleaning solution is not particularly limited, but when the cleaning solution contains one type of component B, it is preferably 0.5% by mass or less, more preferably 0.1% by mass or less, and even more preferably 0.05% by mass or less, relative to the total mass of the cleaning solution. The lower limit is not particularly limited, but it is preferably 0.0001% by mass or more, more preferably 0.0005% by mass or more, and even more preferably 0.001% by mass or more, relative to the total mass of the cleaning solution. When the cleaning solution contains two or more types of component B, the content of each component B relative to the total mass of the cleaning solution is preferably 0.5% by mass or less, more preferably 0.1% by mass or less, and even more preferably 0.05% by mass or less. Although there is no particular lower limit, the content of each component B relative to the total mass of the cleaning solution is preferably 0.0001% by mass or more, more preferably 0.0005% by mass or more, and even more preferably 0.001% by mass or more.

[0074] Component B may be used alone or in combination of two or more. The total content of component B in the cleaning liquid is not particularly limited, but is preferably 0.0001 to 1 mass %, more preferably 0.0005 to 0.2 mass %, and even more preferably 0.001 to 0.1 mass %.

[0075] <Organic solvents> The cleaning liquid may contain an organic solvent other than the above components. The organic solvent is preferably a hydrophilic organic solvent. In this specification, the term "hydrophilic organic solvent" refers to an organic solvent that dissolves at 0.1 g or more in 100 g of water at 25° C. The hydrophilic organic solvent is preferably an organic solvent that can be uniformly mixed with water at any mixing ratio. Examples of hydrophilic organic solvents other than the above components include amide-based solvents, sulfur-containing solvents, and ketone-based solvents.

[0076] Examples of amide solvents include N,N-dimethylformamide, 1-methyl-2-pyrrolidone, 2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 2-pyrrolidinone, formamide, N-methylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropanamide, and hexamethylphosphoric triamide. Examples of sulfur-containing solvents include dimethyl sulfone, dimethyl sulfoxide, and sulfolane. Examples of ketone solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

[0077] The organic solvents may be used alone or in combination of two or more. When the cleaning liquid contains an organic solvent, the content of the organic solvent is preferably 0.001 to 20 mass %, more preferably 0.01 to 10 mass %, based on the total mass of the cleaning liquid.

[0078] <Chelating agent> The cleaning solution may contain a chelating agent. The chelating agent is a compound that has the function of chelating with a metal element, and as a result, has the function of removing residues such as etching residues and ashing residues. Examples of the chelating agent include polyaminopolycarboxylic acids and polycarboxylic acids.

[0079] Polyaminopolycarboxylic acids are compounds having multiple amino groups and multiple carboxy groups in one molecule, and examples thereof include mono- or polyalkylenepolyaminepolycarboxylic acids, polyaminoalkanepolycarboxylic acids, polyaminoalkanolpolycarboxylic acids, and hydroxyalkyletherpolyaminepolycarboxylic acids. More specific examples of polyaminopolycarboxylic acids include butylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetrapropionic acid, triethylenetetraminehexaacetic acid, 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, ethylenediaminedipropionic acid, 1,6-hexamethylene-diamine-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, and (hydroxyethyl)ethylenediaminetriacetic acid.

[0080] A polycarboxylic acid is a compound having multiple carboxylic acid groups in one molecule, but does not include the above-mentioned polyaminopolycarboxylic acids. Polycarboxylic acids include, for example, citric acid, malonic acid, maleic acid, succinic acid, malic acid, tartaric acid, and citric acid.

[0081] The cleaning solution may contain a chelating agent other than those described above, such as at least one biguanide compound selected from the group consisting of compounds having a biguanide group and salts thereof. In addition, the chelating agents described in JP-A-2017-504190 can also be used, and the contents of the above document are incorporated herein by reference.

[0082] The chelating agent may be used alone or in combination of two or more. When the cleaning liquid contains a chelating agent, the content of the chelating agent is preferably 0.01 to 10% by mass relative to the total mass of the cleaning liquid.

[0083] <Fluorine-containing compounds> The cleaning liquid may contain a fluorine-containing compound. Examples of fluorine-containing compounds include hydrofluoric acid, ammonium fluoride, tetramethylammonium fluoride, and tetrabutylammonium fluoride, with hydrofluoric acid being preferred. The fluorine-containing compounds may be used alone or in combination of two or more. When the cleaning liquid contains a fluorine-containing compound, the content thereof is preferably 0.01 to 5.0% by mass relative to the total mass of the cleaning liquid.

[0084] <Metal components> The cleaning liquid may contain a metal component. The metal component includes metal particles and metal ions. For example, the content of the metal component refers to the total content of the metal particles and metal ions. The cleaning solution may contain either metal particles or metal ions, or both.

[0085] Examples of metal atoms contained in the metal component include metal atoms selected from the group consisting of Ag, Al, As, Au, Ba, Ca, Cd, Co, Cr, Cu, Fe, Ga, Ge, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sn, Sr, Ti, and Zn. The metal component may contain one type of metal atom or two or more types of metal atoms. The metal particles may be a simple substance or an alloy, or the metal may exist in a state associated with an organic substance. The metal components may be metal components that are inevitably contained in each component (raw material) contained in the cleaning solution, or metal components that are inevitably contained during the production, storage, and / or transportation of the cleaning solution, or may be intentionally added. When the cleaning liquid contains a metal component, the content of the metal component is often 0.01 mass ppt to 10 mass ppm, preferably 0.1 mass ppt to 1 mass ppm, and more preferably 0.1 mass ppt to 100 mass ppb, relative to the total mass of the cleaning liquid.

[0086] The type and content of metal components in the cleaning solution can be measured by ICP-MS (Single Nano Particle Inductively Coupled Plasma Mass Spectrometry). In ICP-MS, the content of the target metal component is measured regardless of the form of its existence. Therefore, the total mass of the target metal particles and metal ions is quantified as the content of the metal component. For the ICP-MS measurement, for example, Agilent 8800 triple quadrupole ICP-MS (inductively coupled plasma mass spectrometry, for semiconductor analysis, option #200) and Agilent 8900 manufactured by Agilent Technologies, and NexION350S manufactured by PerkinElmer can be used.

[0087] The method for adjusting the content of each metal component in the cleaning solution is not particularly limited. For example, the content of metal components in the cleaning solution can be reduced by performing a known process for removing metals from the cleaning solution and / or from raw materials containing each component used to prepare the cleaning solution. Furthermore, the content of metal components in the cleaning solution can be increased by adding a compound containing metal ions to the cleaning solution.

[0088] <Corrosion inhibitor> The cleaning liquid may contain a corrosion inhibitor. The anticorrosive agent functions to prevent corrosion of the metal layer due to over-etching or the like by coordinating with the surface of the metal layer (particularly the W-containing layer or the Co-containing layer) that will become the wiring of the semiconductor device, thereby forming a film. In this specification, the above-mentioned azole compounds and chelating agents (compounds having chelating ability) are not included in the anticorrosive agents.

[0089] Examples of corrosion inhibitors include tritolyl phosphate, adenine, cytosine, guanine, thymine, phosphate inhibitors, propanethiol, silanes, benzohydroxamic acids, heterocyclic nitrogen inhibitors, ascorbic acid, thiourea, 1,1,3,3-tetramethylurea, urea, urea derivatives, uric acid, potassium ethylxanthogenate, glycine, dodecylphosphonic acid, iminodiacetic acid, boric acid, nitrilotriacetic acid, 2,3,5-trimethylpyrazine, 2-ethyl-3,5-dimethylpyrazine, quinoxaline, acetylpyrrole, pyridazine, histadine, pyrazine, glutathione (reduced form), cysteine, cystine, thiophene, mercaptopyridine N-oxide, thiamine HCl, tetraethylthiuram disulfide, ascorbic acid, catechol, t-butylcatechol, phenol, and pyrogallol.

[0090] Examples of the anticorrosive agent include a compound represented by the following formula (A) and a compound represented by the following formula (B).

[0091] [ka]

[0092] In the above formula (A), R 1A ~R 5A each independently represents a hydrogen atom, a substituted or unsubstituted hydrocarbon group, a hydroxy group, a carboxy group, or a substituted or unsubstituted amino group, provided that the structure contains at least one group selected from a hydroxy group, a carboxy group, and a substituted or unsubstituted amino group. In the above formula (B), R 1B ~R 4B each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group.

[0093] Examples of compounds represented by formula (A) include 1-thioglycerol, L-cysteine, and thiomalic acid. Examples of the compound represented by formula (B) include catechol and t-butylcatechol.

[0094] The anticorrosive agent may be used alone or in combination of two or more. When the cleaning liquid contains an anticorrosive agent, the content of the anticorrosive agent is preferably 0.01 to 5 mass %, more preferably 0.05 to 5 mass %, and even more preferably 0.1 to 3 mass %, relative to the total mass of the cleaning liquid.

[0095] The anticorrosive agent to be used is preferably of a high purity grade, and more preferably is further purified before use. The method for purifying the corrosion inhibitor is not particularly limited, and 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 applied in combination.

[0096] The cleaning liquid may contain additives other than the above components, such as surfactants, antifoaming agents, rust inhibitors, and preservatives.

[0097] [Physical properties of cleaning solution] <ph> The pH of the present cleaning solution is preferably 7 or higher, in order to stably exhibit excellent cleaning performance for dry etching residues. From the above viewpoint, the pH of the washing liquid is more preferably 8 to 14, further preferably 9 to 12, and particularly preferably 9 to 11. The pH of the cleaning solution is a value obtained by measurement at 25°C using a known pH meter.

[0098] <Coarse particles> The cleaning liquid preferably contains substantially no coarse particles. Coarse particles refer to particles with a diameter of 0.2 μm or more when considered as spherical. Furthermore, "substantially free of coarse particles" means that when the cleaning solution is measured using a commercially available light scattering liquid particle measurement device, there are 10 or fewer particles with a diameter of 0.2 μm or more per mL of cleaning solution. The coarse particles contained in the cleaning solution include particles such as dust, dirt, organic solids, and inorganic solids contained as impurities in the raw materials, as well as particles such as dust, dirt, organic solids, and inorganic solids brought in as contaminants during preparation of the cleaning solution, which ultimately remain as particles without dissolving in the cleaning solution. The amount of coarse particles present in the cleaning liquid can be measured in the liquid phase using a commercially available measuring device that uses a laser as a light source and is a liquid-borne particle measuring method based on light scattering. Coarse particles can be removed by, for example, filtering or other processes.

[0099] [Kit and concentrate] The cleaning solution may be prepared as a kit for preparing the cleaning solution by dividing the raw materials into multiple parts. An example of the kit for preparing the cleaning solution is a kit (hereinafter also referred to as "kit A") including a first liquid containing at least a hydroxylamine compound and a second liquid containing at least component A. The first liquid of kit A may contain components other than the hydroxylamine compound, but preferably does not contain any of component A, an azole compound, or a basic compound. The second liquid of kit A may contain components other than component A, but preferably does not contain a hydroxylamine compound.

[0100] The content of each component contained in the first and second liquids provided in the kit is not particularly limited, but it is preferable that the content of each component in the cleaning liquid prepared by mixing the first and second liquids is an amount that corresponds to the above-mentioned preferred content. The pH of the first and second liquids provided in the kit is not particularly limited, as long as the pH of each liquid is adjusted so that the pH of the cleaning liquid prepared by mixing the first and second liquids falls within the above range.

[0101] The cleaning solution may also be prepared as a concentrated solution. In this case, it can be diluted with a diluent before use. The diluent is not particularly limited, but may be a diluent made of water, alcohol, the above organic solvents, or a mixture thereof. In other words, the kit for preparing the cleaning solution may be a kit including the above cleaning solution in the form of a concentrated solution and the above diluent.

[0102] [Application] This cleaning liquid is a cleaning liquid for semiconductor devices. In this specification, "for semiconductor devices" means that it is used during the manufacture of semiconductor devices. This cleaning liquid can be used in any cleaning process included in the process of manufacturing semiconductor devices, for example, in a cleaning process for removing etching residues and ashing residues present on a semiconductor substrate (hereinafter simply referred to as "substrate"). In this specification, etching residues and ashing residues are collectively referred to as residues. This cleaning liquid may also be used in a cleaning process for removing residues such as metal impurities or fine particles from a substrate after chemical mechanical polishing. In particular, this cleaning liquid is suitably used as a cleaning liquid for removing residues attached to a metal layer (particularly a Co-containing layer, a W-containing layer, or a TiN-containing layer). The cleaning liquid can also be used as a treatment liquid, such as a prewet liquid applied to a substrate to improve the coatability of the composition before the step of forming a resist film using an actinic ray- or radiation-sensitive composition, a solution used to remove various resist films for pattern formation (e.g., a remover liquid and a stripper liquid), and a solution used to remove permanent films (e.g., a color filter, a transparent insulating film, and a resin lens) from a semiconductor substrate (e.g., a remover liquid and a stripper liquid). Note that, because the semiconductor substrate after removal of the permanent film may be used again in the manufacture of a semiconductor device, the removal of the permanent film is considered to be included in the manufacturing process of the semiconductor device. The cleaning solution can also be used as an etching solution for metal oxides such as cobalt oxide and copper oxide (including composite oxides made of multiple metal oxides). The cleaning liquid may be used for only one of the above uses, or for two or more uses.

[0103] [Cleaning solution manufacturing method] <Cleaning solution preparation process> The method for producing the cleaning solution is not particularly limited, and any known production method can be applied. For example, the method for producing the cleaning solution includes at least a cleaning solution preparation step of mixing the components described above to prepare the cleaning solution. In the cleaning solution preparation step, the order in which the components are mixed is not particularly limited. The concentrated solution and each solution provided in the kit are preferably produced by the same method as above. The method for preparing the kit is not particularly limited. For example, after preparing the first and second liquids described above, the first and second liquids can be placed in different containers to prepare a kit for preparing a cleaning liquid.

[0104] <Metal removal process> Before use in the cleaning solution preparation step, it is preferable to perform a metal removal step for each component, in which metals are removed from a raw material containing each component to obtain a purified product containing each component. By performing the metal removal step for each component and preparing a cleaning solution using each component contained in the obtained purified product, the content of metal components in the cleaning solution can be further reduced. The method for removing metals from raw materials containing each component (hereinafter also referred to as "material to be purified") is not particularly limited, and known methods can be applied, such as a method of passing the material to be purified through at least one resin selected from the group consisting of chelating resins and ion exchange resins, and a method of passing the material to be purified through a metal ion adsorption filter.

[0105] The components to be subjected to the metal removal step are not particularly limited as long as they are the components contained in the above-mentioned cleaning solution (excluding metal components). When the cleaning solution contains a chelating agent, the content of metal components contained in the raw material containing the chelating agent tends to be higher than that of other components, so it is more preferable to prepare the cleaning solution using a purified product containing a chelating agent obtained by subjecting the raw material containing the chelating agent to the metal removal step. The material to be purified that is subjected to the metal removal step may contain compounds other than the target material, and preferably contains a solvent. Examples of the solvent include water and organic solvents, with water being preferred. The content of the target substance in the product to be purified can be appropriately determined depending on the type of the target substance and the specific metal removal treatment, and may be, for example, 1 to 100 mass % relative to the total mass of the product to be purified, and preferably 10 to 50 mass %.

[0106] The method for passing the material to be purified through at least one resin selected from the group consisting of chelating resins and ion exchange resins is not particularly limited, but includes a method in which the material to be purified is passed through a chelating resin and / or an ion exchange resin filled in a container. The chelating resin and / or ion exchange resin through which the material to be purified is passed may be one type alone or two or more types may be used. In addition, the material to be purified may be passed through the same chelating resin and / or ion exchange resin two or more times. In the metal removal step, both a chelating resin and an ion exchange resin may be used. In this case, the chelating resin and the ion exchange resin may be used in a double bed or a mixed bed. The container is not particularly limited as long as it can be filled with a chelating resin and / or an ion exchange resin and allows the product to be purified to pass through the filled chelating resin and / or ion exchange resin, and examples thereof include a column, a cartridge, and a packed tower.

[0107] The ion exchange resin used in the metal removal step includes a cation exchange resin and an anion exchange resin. The cation exchange resin may be used in a single bed, or a combination of a cation exchange resin and an anion exchange resin may be used in a double bed or a mixed bed. As the cation exchange resin, known cation exchange resins can be used, for example, sulfonic acid type cation exchange resins and carboxylic acid type cation exchange resins. The material of the cation exchange resin is not particularly limited, but gel type cation exchange resins are preferred. As the cation exchange resin, commercially available products can be used, such as Amberlite (registered trademark, the same applies hereinafter) IR-124, Amberlite IR-120B, Amberlite IR-200CT, Allite (registered trademark, the same applies hereinafter) DS-1, and Allite DS-4 (all manufactured by Organo Corporation); Duolite (registered trademark, the same applies hereinafter) C20J, Duolite C20LF, Duolite C255LFH, and Duolite C-433LF (all manufactured by Sumika Chemtex); DIAION (registered trademark, the same applies hereinafter) SK-110, DIAION SK1B, and DIAION SK1BH (all manufactured by Mitsubishi Chemical Corporation); and Purolite (registered trademark, the same applies hereinafter) S957 and Purolite S985 (all manufactured by Purolite Corporation).

[0108] The chelating resin is not particularly limited as long as it is a resin having a chelating group that has the function of chelating with a metal. Examples of the chelating group include an iminodiacetic acid group, an iminopropionic acid group, an aminophosphonic acid group such as an aminomethylenephosphonic acid group (-NH-CH-POH), a polyamine group, a glucamine group such as an N-methylglucamine group, an aminocarboxylic acid group, a dithiocarbamic acid group, a thiol group, an amidoxime group, and a pyridine group. An iminodiacetic acid group or an aminophosphonic acid group is preferred, and an aminophosphonic acid group is more preferred. These chelating groups may form salts with counter ions, but it is preferable that they do not form salts, as this allows for a further reduction in the metal content. That is, the chelating resin is preferably an H-type chelating resin. H-type chelating resins can be obtained by contacting a metal ion type chelating resin, such as a Na-type, Ca-type, or Mg-type, with a mineral acid for acid treatment. The substrate of the chelating resin is not particularly limited, and examples thereof include styrene-divinylbenzene copolymer and styrene-ethylstyrene-divinylbenzene copolymer.

[0109] As the chelating resin, commercially available products can be used, such as Duolite ES371N, Duolite C467, Duolite C747UPS, Sumikelate (registered trademark, the same applies hereinafter) MC760, Sumikelate MC230, Sumikelate MC300, Sumikelate MC850, Sumikelate MC640, Sumikelate MC900, and Sumikelate MC960 (all manufactured by Sumika Chemtex Co., Ltd.); Purolite S106, Purolite S910, Purolite S914, Purolite S920, Purolite S930, Purolite S950, Purolite S957, and Purolite S985 (all manufactured by Purolite Co., Ltd.); and Allite DS-21, Amberlite IRC748, and Amberlite IRC747 (all manufactured by Organo Corporation).

[0110] When the cleaning solution contains a chelating agent, the metal removal step performed on the raw material containing the chelating agent preferably includes a step of passing the material to be purified through at least one resin selected from the group consisting of chelating resins and ion exchange resins, from the viewpoint of further reducing the content of metal components in the cleaning solution, and more preferably includes a step of passing the material to be purified through a chelating resin. Among these, it is even more preferable to include a step of passing the material to be purified through a chelating resin having an aminophosphonic acid group, from the viewpoint of further reducing the content of Ca and / or Zn in the raw material containing the chelating agent. Commercially available chelating resins having aminophosphonic acid groups include Duolite C467, Duolite C747UPS, Sumichelate MC960, Purolite S950, Orlite DS-21, and Amberlite IRC747, with Orlite DS-21 being preferred. Orlite DS-21 is an H-type chelating resin in which aminomethylphosphonic acid groups are introduced as chelating groups into a base material made of a styrene-ethylstyrene-divinylbenzene copolymer, and is commercially available in a state containing 30 to 45% by mass of the above chelating resin and 55 to 70% by mass of water.

[0111] The conditions for passing the material to be purified through the ion exchange resin are not particularly limited, and may be carried out according to a known method. The space velocity (SV) at which the material to be purified passes through the ion exchange resin while in contact with the resin is preferably 1-20, and more preferably 1-10. The temperature of the material to be purified that comes into contact with the ion exchange resin is preferably 10 to 40°C, more preferably 15 to 30°C.

[0112] As a step for removing metals from the material to be purified, an adsorption purification treatment step of metal components using silicon carbide, as described in International Publication No. 2012 / 043496, the description of which is incorporated herein by reference, may be carried out. Furthermore, in the step of removing metals from the material to be purified, metal particles contained in the material to be purified may be removed using a filter that can be used in the filtering step described below.

[0113] The metals removed from the raw material by the metal removal step are not particularly limited, and examples include Li, Na, Mg, Al, K, Ca, Cr, Mn, Fe, Ni, Zn, Pb, etc. The purified product obtained by the metal removal step has a reduced content of the above metals compared to the raw material. The metal content in the purified product is not particularly limited. For example, the ratio of the content of each metal element in the metal component to the content of the chelating agent in the purified product containing the chelating agent is 1.0 × 10 in mass ratio. -6 Preferably, it is 1.0 x 10 or less. -7 More preferably, it is 1.0×10 or less. -8 It is more preferable that: Furthermore, in the purified product containing the chelating agent obtained by the metal removal step, the ratio of the Ca component content to the Na component content is preferably 1.0 or more by mass (the Ca component content is greater than the Na component content), more preferably 1.1 or more, and even more preferably 1.2 or more. There is no particular upper limit, but the ratio of the Ca component content to the Na component content is preferably 50 or less by mass. The type and content of metals in the raw material and purified material can be measured according to the method described as the method for measuring the type and content of metal components in the cleaning solution.

[0114] <Filtration process> The above-mentioned production method preferably includes a filtration step of filtering the liquid to remove foreign matter, coarse particles, and the like from the liquid. The filtration method is not particularly limited, and any known filtration method can be used, among which filtration using a filter is preferred.

[0115] The filter used for filtering can be any filter that has been conventionally used for filtering purposes without any particular limitation. Examples of materials that constitute the filter include fluororesins such as PTFE (polytetrafluoroethylene), polyamide resins such as nylon, polyolefin resins (including high density and ultra-high molecular weight) such as polyethylene and polypropylene (PP), and polyarylsulfone. Among these, polyamide resins, PTFE, polypropylene (including high density polypropylene), and polyarylsulfone are preferred. By using a filter made of these materials, highly polar foreign matter that is likely to cause defects can be more effectively removed from the cleaning liquid.

[0116] The lower limit of the critical surface tension of the filter is preferably 70 mN / m or more, and the upper limit is preferably 95 mN / m or less. In particular, the critical surface tension of the filter is preferably 75 to 85 mN / m. The critical surface tension values ​​are nominal values ​​provided by the manufacturer. By using a filter with a critical surface tension in the above range, highly polar foreign matter that is likely to cause defects can be more effectively removed from the cleaning liquid.

[0117] The pore size of the filter is preferably about 0.001 to 1.0 μm, more preferably about 0.02 to 0.5 μm, and even more preferably about 0.01 to 0.1 μm. By setting the pore size of the filter within the above range, it becomes possible to reliably remove fine foreign matter contained in the cleaning liquid while suppressing filtration clogging.

[0118] When using filters, different filters may be combined. In this case, filtering with the first filter may be performed only once or two or more times. When different filters are combined to perform filtering two or more times, the filters may be of the same type or different types, but it is preferable that they are of different types. Typically, it is preferable that the first filter and the second filter differ in at least one of the pore size and constituent material. It is preferable that the pore size of the second or subsequent filtering steps be the same or smaller than that of the first filtering step. It is also possible to combine first filters with different pore sizes within the above range. The pore size here refers to the nominal value of the filter manufacturer. Commercially available filters can be selected from various filters provided by, for example, Nippon Pall Corporation, Advantec Toyo Co., Ltd., Nippon Integris Co., Ltd. (formerly Nippon Microlith Co., Ltd.), or Kitz Microfilter Co., Ltd. Other usable filters include the polyamide "P-Nylon Filter (pore size 0.02 μm, critical surface tension 77 mN / m)" (manufactured by Nippon Pall Corporation), the high-density polyethylene "PE Clean Filter (pore size 0.02 μm)" (manufactured by Nippon Pall Corporation), and the high-density polyethylene "PE Clean Filter (pore size 0.01 μm)" (manufactured by Nippon Pall Corporation).

[0119] The second filter can be made of the same material as the first filter. It can have the same pore size as the first filter. When the second filter has a smaller pore size than the first filter, the ratio of the pore size of the second filter to the pore size of the first filter (pore size of the second filter / pore size of the first filter) is preferably 0.01 to 0.99, more preferably 0.1 to 0.9, and even more preferably 0.3 to 0.9. By setting the pore size of the second filter within the above range, fine foreign matter mixed in the cleaning liquid can be more reliably removed.

[0120] For example, the filtering with the first filter may be performed on a mixed liquid containing some of the components of the cleaning liquid, and the remaining components may be mixed with this to prepare a cleaning liquid, after which the second filtering may be performed. The filter to be used is preferably treated before filtering the cleaning liquid. The liquid to be used for this treatment is not particularly limited, but is preferably the cleaning liquid, a concentrated liquid, or a liquid containing a component contained in the cleaning liquid.

[0121] When filtering is performed, the upper limit of the temperature during filtering is preferably room temperature (25°C) or lower, more preferably 23°C or lower, and even more preferably 20°C or lower. The lower limit of the temperature during filtering is preferably 0°C or higher, more preferably 5°C or higher, and even more preferably 10°C or higher. Filtering can remove particulate foreign matter and / or impurities, but when performed at the above temperatures, the amount of particulate foreign matter and / or impurities dissolved in the cleaning liquid is reduced, making filtering more efficient.

[0122] <Static elimination process> The above-mentioned production method may further comprise a step of neutralizing at least one selected from the group consisting of a cleaning solution, a concentrated solution, and a kit. Specific methods for neutralizing are described below.

[0123] All steps of the above-mentioned manufacturing method are preferably carried out in a clean room. The clean room preferably meets the 14644-1 clean room standard. The clean room preferably meets any one of ISO (International Organization for Standardization) Class 1, ISO Class 2, ISO Class 3, and ISO Class 4, more preferably ISO Class 1 or ISO Class 2, and even more preferably ISO Class 1.

[0124] <Container> The container for storing the above-mentioned cleaning solution, concentrated solution or kit is not particularly limited, and any known container can be used as long as corrosiveness of the solution does not pose a problem. The container is preferably one for semiconductor applications, with a high degree of cleanliness inside and little elution of impurities. Commercially available examples of the container include the "Clean Bottle" series manufactured by Aicello Chemical Co., Ltd. and the "Pure Bottle" manufactured by Kodama Resin Industry Co., Ltd. Furthermore, in order to prevent impurities from being mixed into raw materials and chemical solutions, it is also preferable to use a multilayer container whose inner wall has a six-layer structure made of six types of resin, or a multilayer container whose inner wall has a seven-layer structure made of six types of resin. Examples of such containers include, but are not limited to, the containers described in JP 2015-123351 A. The inner wall of the container is preferably formed of or coated with one or more resins selected from the group consisting of polyethylene resin, polypropylene resin, and polyethylene-polypropylene resin, or a resin other than these, or a metal such as stainless steel, Hastelloy, Inconel, or Monel.

[0125] As the different resin, a fluororesin (perfluororesin) can be preferably used. By using a container whose inner wall is formed of or coated with a fluororesin, the occurrence of the problem of elution of ethylene or propylene oligomers can be suppressed compared to when a container whose inner wall is formed of or coated with a polyethylene resin, a polypropylene resin, or a polyethylene-polypropylene resin is used. A specific example of a container having such an inner wall is the FluoroPure PFA composite drum manufactured by Entegris, Inc. In addition, the containers described on page 4 of JP-A-3-502677, page 3 of WO 2004 / 016526, and pages 9 and 16 of WO 99 / 46309 can also be used.

[0126] In addition to the above-mentioned fluorine-based resin, quartz and electrolytically polished metal materials (that is, metal materials that have been electrolytically polished) are also preferably used for the inner wall of the container. The metal material used to produce the electropolished metal material preferably contains at least one selected from the group consisting of chromium and nickel, and the total content of chromium and nickel is more than 25 mass% relative to the total mass of the metal material, such as stainless steel and nickel-chromium alloy. The total content of chromium and nickel in the metal material is preferably 25 mass % or more, more preferably 30 mass % or more, based on the total mass of the metal material. The upper limit of the total content of chromium and nickel in the metal material is not particularly limited, but is generally preferably 90 mass % or less.

[0127] The stainless steel is not particularly limited, and known stainless steels can be used. Among them, alloys containing 8% or more by mass of nickel are preferred, and austenitic stainless steels containing 8% or more by mass of nickel are more preferred. Examples of austenitic stainless steels include SUS (Steel Use Stainless) 304 (Ni content: 8% by mass, Cr content: 18% by mass), SUS304L (Ni content: 9% by mass, Cr content: 18% by mass), SUS316 (Ni content: 10% by mass, Cr content: 16% by mass), and SUS316L (Ni content: 12% by mass, Cr content: 16% by mass).

[0128] The nickel-chromium alloy is not particularly limited, and any known nickel-chromium alloy can be used. Among them, a nickel-chromium alloy containing 40 to 75 mass % of nickel and 1 to 30 mass % of chromium is preferred. Examples of nickel-chromium alloys include Hastelloy (trade name, the same applies hereinafter), Monel (trade name, the same applies hereinafter), and Inconel (trade name, the same applies hereinafter), etc. More specific examples include Hastelloy C-276 (Ni content: 63 mass%, Cr content: 16 mass%), Hastelloy-C (Ni content: 60 mass%, Cr content: 17 mass%), Hastelloy C-22 (Ni content: 61 mass%, Cr content: 22 mass%), etc. Furthermore, the nickel-chromium alloy may further contain boron, silicon, tungsten, molybdenum, copper, cobalt, and the like in addition to the above alloy, as required.

[0129] The method for electrolytically polishing a metal material is not particularly limited, and any known method can be used, such as the methods described in paragraphs

[0011] to

[0014] of JP 2015-227501 A and paragraphs

[0036] to

[0042] of JP 2008-264929 A.

[0130] It is presumed that the chromium content in the surface passive layer of the metal material becomes higher than the chromium content in the parent phase by electrolytic polishing, and therefore, it is presumed that metal elements are less likely to leak into the cleaning solution from the inner wall coated with the electrolytically polished metal material, making it possible to obtain a cleaning solution with reduced specific metal elements. The metal material is preferably buffed. The buffing method is not particularly limited, and known methods can be used. The size of the abrasive grains used for the buffing finish is not particularly limited, but #400 or smaller is preferred because it tends to reduce the surface irregularities of the metal material. It is preferable that the buffing be carried out before the electrolytic polishing. The metal material may also be treated by one or a combination of two or more of multiple steps of buffing using different grit sizes of abrasive grains, acid washing, and magnetic fluid polishing.

[0131] It is preferable to wash the inside of these containers before filling them. The liquid used for washing may be selected appropriately depending on the application, but is preferably the above-mentioned washing liquid, a liquid obtained by diluting the above-mentioned washing liquid, or a liquid containing at least one of the components added to the above-mentioned washing liquid.

[0132] To prevent the cleaning solution from changing during storage, the container may be filled with an inert gas (such as nitrogen or argon) with a purity of 99.99995% by volume or higher. A gas with a low water content is particularly preferred. The container may be transported or stored at room temperature, but the temperature may be controlled to a range of -20°C to 20°C to prevent deterioration.

[0133] [Substrate processing method] The cleaning solution can be used by contacting it with a substrate containing a metal-based material, which is typically a material containing metal. In this case, the substrate may contain multiple types of metal-based materials. Furthermore, the cleaning solution may dissolve at least one of the multiple types of metal-based materials that may be contained.

[0134] The metallic material may contain metal atoms (such as cobalt (Co), ruthenium (Ru), molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), and / or tantalum (Ta)), and examples thereof include elemental metals, alloys, metal oxides (which may be composite oxides), and metal nitrides (which may be composite nitrides). Examples of metallic materials included in the substrate include materials containing at least one element selected from the group consisting of elemental metals, alloys, metal oxides, and metal nitrides, and at least one element selected from the group consisting of carbon, nitrogen, boron, and phosphorus as a dopant. The content of metal atoms in the metal-based material is preferably 30 to 100 mass %, more preferably 40 to 100 mass %, and even more preferably 50 to 100 mass %, based on the total mass of the metal-based material. When the metal-based material contains the dopant, the content of the metal atom dopant is preferably 0.1 to 50 mass %, more preferably 10 to 40 mass %, based on the total mass of the metal-based material, and in this case, the content of the metal atom in the metal-based material is preferably 30 to 99.9 mass %, more preferably 60 to 90 mass %, based on the total mass of the metal-based material.

[0135] [How to clean the substrate] The cleaning liquid is used in a method for cleaning a semiconductor substrate (hereinafter, also simply referred to as a "cleaning method") that includes a cleaning step B for cleaning a substrate having a metal layer. The cleaning method may include a cleaning liquid preparation step A for preparing the cleaning liquid before the cleaning step B. In the following description of the cleaning method, an example is shown in which the cleaning liquid preparation process A is carried out before the cleaning process B, but the cleaning method is not limited to this example and may be carried out, for example, using the above-mentioned cleaning liquid prepared in advance.

[0136] [Item to be cleaned] The object to be cleaned in the cleaning method is not particularly limited as long as it is a substrate having a metal layer, and is preferably a substrate having a metal layer containing at least W. The object to be cleaned is also preferably a substrate having a metal layer containing Co, Ti, Al, Ru, Mo, Ta or Cu, and is also preferably a substrate further having a SiN, SiOC or SiOx layer in addition to a metal layer. The object to be cleaned may be, for example, a laminate having a metal layer, an interlayer insulating film, and a metal hard mask, in this order, on a substrate. The laminate may further have holes formed from the surface (openings) of the metal hard mask toward the substrate, exposing the surface of the metal layer, by undergoing a dry etching process or the like. There are no particular limitations on the method for producing the laminate having holes as described above. Typically, a method includes performing a dry etching step using the metal hard mask as a mask on a pre-treatment laminate having a substrate, a metal layer, an interlayer insulating film, and a metal hard mask in this order, and etching the interlayer insulating film so as to expose the surface of the metal layer, thereby providing holes penetrating the metal hard mask and the interlayer insulating film. The method for producing the metal hard mask is not particularly limited, and examples thereof include a method in which a metal layer containing a predetermined component is first formed on an interlayer insulating film, a resist film having a predetermined pattern is then formed thereon, and the metal layer is then etched using the resist film as a mask to produce a metal hard mask (i.e., a film in which the metal layer is patterned). The laminate may also include layers other than the above-mentioned layers, such as an etching stop film, a barrier layer, and / or an anti-reflection layer.

[0137] FIG. 1 is a schematic cross-sectional view showing an example of a laminate that is an object to be cleaned in the cleaning method. 1 includes a substrate 1 on which a metal layer 2, an etching stop layer 3, an interlayer insulating film 4, and a metal hard mask 5 are formed in this order, and a hole 6 is formed by a dry etching process to expose the metal layer 2 at a predetermined position. In other words, the object to be cleaned shown in FIG. 1 is a laminate including a substrate 1, a metal layer 2, an etching stop layer 3, an interlayer insulating film 4, and a metal hard mask 5, in this order, and a hole 6 that penetrates from the surface of the metal hard mask 5 to the surface of the metal layer 2 at the position of the opening of the metal hard mask 5. An inner wall 11 of the hole 6 includes a cross-sectional wall 11a formed from the etching stop layer 3, the interlayer insulating film 4, and the metal hard mask 5, and a bottom wall 11b formed from the exposed metal layer 2, and dry etching residues 12 are attached to the inner wall 11.

[0138] The cleaning method using this cleaning solution can be suitably used for cleaning aimed at removing dry etching residues 12 attached to laminates having the above-mentioned metal layers (particularly, W-containing layer, Co-containing layer, and / or TiN-containing layer). That is, this cleaning solution is excellent in removing performance (residue removal ability) of dry etching residues 12 from these laminates, and also excellent in inhibiting dissolution of the inner wall 11 of the object to be cleaned (for example, metal layer 2 and etching stop layer 3, etc.).

[0139] The object to be cleaned in the cleaning method is not limited to the embodiment shown in Fig. 1. For example, the object to be cleaned may be a laminate including a substrate and a metal layer, an etching stop layer, an interlayer insulating film, and a metal hard mask in this order, in which holes penetrating the interlayer insulating film are formed by a dry etching process at the positions of the openings in the metal hard mask, exposing the etching stop layer. The inner walls of the holes in this laminate are composed of cross-sectional walls where at least the side walls of the interlayer insulating film and the metal hard mask are exposed, and a bottom wall made of the exposed etching stop layer. A cleaning method using this laminate as the object to be cleaned can be suitably applied to cleaning aimed at removing dry etching residues adhering to the inner walls. In the cleaning method using the present cleaning solution, at least a part of the etching stop layer may be removed simultaneously with the removal of dry etching residues from the laminate. The cleaning method may also be carried out on a laminate that has been subjected to a dry ashing step after a dry etching step. The materials constituting each layer of the laminate will now be described.

[0140] <Metal hard mask> The metal hard mask preferably contains at least one component selected from the group consisting of copper, cobalt, cobalt alloy, tungsten, tungsten alloy, ruthenium, ruthenium alloy, tantalum, tantalum alloy, aluminum oxide, aluminum nitride, aluminum nitride oxide, titanium aluminum, titanium, titanium nitride (TiN), titanium oxide, zirconium oxide, hafnium oxide, tantalum oxide, lanthanum oxide, and yttrium alloy (preferably YSiOx), where x and y are preferably numbers expressed as x=1 to 3 and y=1 to 2, respectively. Examples of materials for the metal hard mask include TiN, WC, WO2, and ZrO2.

[0141] <Interlayer insulating film> The material of the interlayer insulating film is not particularly limited, but is preferably a material with a dielectric constant k of 3.0 or less, more preferably a material with a dielectric constant k of 2.6 or less. Specific examples of materials for the interlayer insulating film include SiOx, SiN, SiOC, and organic polymers such as polyimide, where x is preferably a number from 1 to 3.

[0142] <Etching stop layer> The material of the etching stop layer is not particularly limited. Examples of materials constituting the etching stop layer include SiN, SiON, and SiOCN-based materials, as well as metal oxides such as aluminum oxide (AlOx). Note that x is preferably a number between 1 and 3.

[0143] <Metal layer> The material for forming the metal layer serving as the wiring material and / or plug material is not particularly limited, but preferably contains tungsten. Examples of the material containing tungsten include tungsten itself and alloys of tungsten with other metals. The material for forming the metal layer is also preferably a material containing one or more selected from the group consisting of cobalt, molybdenum, and copper, and may be an alloy of cobalt, molybdenum, or copper with another metal. The metal layer may further contain metals, metal nitrides, and / or alloys other than cobalt, tungsten, ruthenium, molybdenum, and copper. Examples of metals other than cobalt, tungsten, ruthenium, molybdenum, and copper that the metal layer may contain include titanium, titanium-tungsten, titanium nitride, tantalum, tantalum compounds, chromium, chromium oxide, and aluminum. The metal layer may include one or more selected from the group consisting of cobalt, tungsten, ruthenium, molybdenum, and copper, as well as at least one dopant selected from the group consisting of carbon, nitrogen, boron, and phosphorus.

[0144] <Substrate> The term "substrate" as used herein includes, for example, a semiconductor substrate made of a single layer and a semiconductor substrate made of multiple layers. The material constituting the single-layer semiconductor substrate is not particularly limited, but is generally preferably silicon, silicon germanium, a III-V compound such as GaAs, or any combination thereof. In the case of a multi-layer semiconductor substrate, its configuration is not particularly limited, and it may have exposed integrated circuit structures such as interconnect features, such as metal lines and dielectric materials, on a semiconductor substrate such as silicon. Metals and alloys used in the interconnect features include, but are not limited to, aluminum, aluminum alloyed with copper, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, and tungsten. Furthermore, the semiconductor substrate may have layers such as interlayer dielectric layers, silicon oxide, silicon nitride, silicon carbide, and carbon-doped silicon oxide on it.

[0145] (barrier layer) The laminate may have a barrier layer, which is formed between a metal layer serving as a wiring material and / or a plug material on a substrate and an interlayer insulating film, and serves as a layer (film) for preventing diffusion of the wiring material and / or the plug material. The barrier layer may be made of a low-resistance metal material, and preferably contains at least one selected from the group consisting of tantalum or a tantalum compound, titanium or a titanium compound, tungsten or a tungsten compound, and ruthenium, more preferably contains at least one selected from the group consisting of TiN, TiW, Ta, TaN, W, WN, and Ru, and even more preferably contains TiN.

[0146] The method for producing the object to be cleaned is not particularly limited as long as it is a method known in the field of semiconductor substrates. Methods for forming a metal layer (metal-containing film or metal-containing wiring) on ​​a substrate include, for example, sputtering, physical vapor deposition (PVD), atomic layer deposition (ALD), chemical vapor deposition (CVD), and molecular beam epitaxy (MBE). When a metal-containing film is formed by sputtering, PVD, ALD, CVD, or the like, metal-containing substances may also adhere to the back surface of the substrate bearing the metal-containing film (the surface opposite to the metal-containing film side). Alternatively, the above method may be carried out through a predetermined mask to form metal-containing wiring on a substrate. Furthermore, after forming a metal layer on a substrate, the substrate may be subjected to a different process or treatment before being used as the object to be cleaned in the present cleaning method. For example, a substrate having a metal layer may be subjected to dry etching to produce a substrate having dry etching residues containing metal. Dry etching residues are by-products generated by dry etching (e.g., plasma etching), and examples thereof include organic residues derived from photoresists, Si-containing residues derived from interlayer insulating films, and metal-containing residues. Alternatively, a substrate having a metal layer may be subjected to CMP to produce a substrate having metal inclusions.

[0147] The substrate cleaning method will be explained below step by step.

[0148] [Cleaning solution manufacturing process A] The cleaning solution production process A is a process for preparing the cleaning solution. The components used in this process are as described above. Details of this process are as described in the "Cleaning solution production process" section above. The procedure for this step is not particularly limited, and examples thereof include a method of preparing a cleaning solution by stirring and mixing predetermined components. Note that the components may be added all at once or in multiple divided portions. Furthermore, it is preferable that the components contained in the cleaning solution be classified as semiconductor grade or equivalent high purity grade, and that the solution be subjected to filtering to remove foreign matter and / or reduction of ionic components with an ion exchange resin, etc. Furthermore, after mixing the raw material components, it is preferable to further filter to remove foreign matter and / or reduce ionic components with a treatment with an ion exchange resin, etc.

[0149] Furthermore, when the cleaning liquid is a concentrated liquid, the concentrated liquid is diluted 5 to 2000 times to obtain a diluted liquid before performing the cleaning step B, and then the diluted liquid is used to perform the cleaning step B. The solvent for diluting the concentrated liquid is preferably at least one selected from the group consisting of water, alcohol, and aprotic polar solvents contained in the cleaning liquid.

[0150] [Cleaning process B] Examples of the object to be cleaned in the cleaning step B include the above-mentioned laminate, and more specifically, a substrate having a metal layer containing W. As described above, the object to be cleaned is exemplified by a laminate in which holes have been formed by a dry etching step (see FIG. 1). Note that dry etching residues adhere to the inside of the holes in this laminate. Alternatively, a laminate that has been subjected to a dry ashing step after the dry etching step may be used as the object to be cleaned.

[0151] The method for bringing the cleaning object into contact with the cleaning liquid is not particularly limited, but examples thereof include a method of immersing the cleaning object in the cleaning liquid contained in a container such as a tank, a method of spraying the cleaning liquid onto the cleaning object, a method of pouring the cleaning liquid onto the cleaning object, and any combination thereof. From the viewpoint of residue removal, the method of immersing the cleaning object in the cleaning liquid is preferred.

[0152] The temperature of the washing liquid in washing step B is preferably 90°C or lower, more preferably 25 to 80°C, even more preferably 30 to 75°C, particularly preferably 40 to 70°C, and most preferably higher than 60°C but not higher than 70°C. This cleaning solution exhibits excellent performance in inhibiting dissolution of metal layers, even under conditions where the temperature of the cleaning solution is relatively high and dissolution of metal layers such as Co-containing layers, W-containing layers, and AlOx layers is likely to proceed.

[0153] The cleaning time can be adjusted depending on the cleaning method used and the temperature of the cleaning solution. When cleaning is performed using an immersion batch method (a batch method in which multiple objects to be cleaned are immersed and treated in a treatment tank), the cleaning time is, for example, within 90 minutes, preferably 1 to 90 minutes, more preferably 5 to 60 minutes, and even more preferably 10 to 45 minutes.

[0154] When cleaning is performed by a single wafer method, the cleaning time is, for example, 10 seconds to 5 minutes, preferably 15 seconds to 4 minutes, more preferably 15 seconds to 3 minutes, and even more preferably 20 seconds to 2 minutes.

[0155] Additionally, mechanical agitation may be used to further enhance the cleaning ability of the cleaning solution. Examples of mechanical agitation methods include circulating the cleaning liquid over the object to be cleaned, flowing or spraying the cleaning liquid over the object to be cleaned, and agitating the cleaning liquid using ultrasound or megasonics.

[0156] [Rinse process B2] The method for cleaning a substrate may further include, after the cleaning step B, a step of rinsing and cleaning the object to be cleaned with a solvent (hereinafter referred to as "rinsing step B2"). The rinsing step B2 is preferably performed consecutively to the cleaning step B, and is a step of rinsing with a rinsing solvent (rinse liquid) for 5 seconds to 5 minutes. The rinsing step B2 may be performed using the mechanical stirring method described above.

[0157] Examples of the solvent for the rinse solution include deionized water (DIW), methanol, ethanol, isopropanol, N-methylpyrrolidinone, γ-butyrolactone, dimethyl sulfoxide, ethyl lactate, and propylene glycol monomethyl ether acetate. The solvent for the rinse liquid is preferably DIW, methanol, ethanol, isopropanol, or a mixture thereof, and more preferably DIW, isopropanol, or a mixture of DIW and isopropanol.

[0158] As a method for contacting the rinse solvent with the object to be cleaned, the above-mentioned method for contacting the object to be cleaned with the cleaning liquid can be similarly applied. The temperature of the rinsing solvent in the rinsing step B2 is preferably 10 to 40°C.

[0159] [Drying process B3] The method for cleaning a substrate may include a drying step B3 of drying the object to be cleaned after the rinsing step B2. The drying method is not particularly limited, and examples of the drying method include spin drying, flowing a dry gas over the object to be cleaned, heating the substrate with a heating means such as a hot plate or an infrared lamp, Marangoni drying, Rotagoni drying, IPA (isopropanol) drying, and any combination thereof. The drying time in the drying step B3 depends on the specific drying method, but is preferably 20 seconds to 5 minutes. When the substrate is dried by heating, the heating temperature is not particularly limited, but is, for example, 50 to 350°C, and preferably 150 to 250°C.

[0160] [Coarse particle removal process H] The substrate cleaning method preferably includes a coarse particle removing step H for removing coarse particles in the cleaning liquid after the cleaning liquid producing step A and before the cleaning step B. By reducing or removing the coarse particles in the cleaning solution, it is possible to reduce the amount of coarse particles remaining on the object to be cleaned after the cleaning process B. As a result, it is possible to suppress pattern damage caused by the coarse particles on the object to be cleaned, and also to suppress the effects of reduced yield and reliability of the device. A specific method for removing coarse particles includes, for example, a method of filtering and purifying the cleaning solution that has been subjected to the cleaning solution production step A using a particle removal membrane with a predetermined particle removal size. The definition of coarse particles is as described above.

[0161] [Static elimination process I, J] The substrate cleaning method preferably includes at least one step selected from the group consisting of a static elimination step I, which is performed before the cleaning liquid preparation step A, to eliminate static electricity from water used in preparing the cleaning liquid, and a static elimination step J, which is performed after the cleaning liquid preparation step A and before the cleaning step B, to eliminate static electricity from the cleaning liquid. The liquid-contacting portion for supplying the cleaning liquid to the object to be cleaned is preferably made of or coated with a material that does not leach metal into the cleaning liquid. Examples of such materials include the materials already described as materials for the inner wall of the container that can be used for the liquid container. The material may be a resin. When the material is a resin, the resin often has low electrical conductivity and is insulating. Therefore, for example, when the cleaning solution is passed through a pipe whose inner wall is formed of or coated with a resin, or when the cleaning solution is filtered and purified using a resin particle removal membrane and a resin ion exchange membrane, the charging potential of the cleaning solution may increase, which may cause an electrostatic hazard. Therefore, in the method for cleaning a substrate, it is preferable to reduce the charged potential of the cleaning liquid by performing at least one of the above-mentioned static elimination step I and static elimination step J. Furthermore, static elimination can further suppress adhesion of foreign matter (such as coarse particles) to the substrate and / or damage (corrosion) to the object to be cleaned. A specific example of a method for eliminating static electricity is a method in which water and / or a cleaning liquid is brought into contact with the conductive material. The contact time for which the water and / or cleaning liquid is brought into contact with the conductive material is preferably 0.001 to 1 second, more preferably 0.01 to 0.1 second. Examples of resins include high-density polyethylene (HDPE), high-density polypropylene (PP), 6,6-nylon, tetrafluoroethylene (PTFE), copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether (PFA), polychlorotrifluoroethylene (PCTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), ethylene-tetrafluoroethylene copolymer (ETFE), and tetrafluoroethylene-hexafluoropropylene copolymer (FEP). Conductive materials include stainless steel, gold, platinum, diamond, and glassy carbon.

[0162] The method for cleaning a substrate may include a cleaning liquid producing step A, a cleaning step B, a waste liquid collecting step C for collecting the waste liquid of the cleaning liquid used in the cleaning step B, a cleaning step D for cleaning a substrate having a newly prepared predetermined layer using the collected waste liquid of the cleaning liquid, and a waste liquid collecting step E for collecting the waste liquid of the cleaning liquid used in the cleaning step D, in which the cleaning step D and the waste liquid collecting step E are repeatedly performed to recycle the waste liquid of the cleaning liquid.

[0163] In the above-described substrate cleaning method, the cleaning liquid preparation step A and the cleaning step B are as described above. Also, in the embodiment in which the waste liquid is reused, it is preferable to have the above-described coarse particle removal step H and the static elimination steps I and J.

[0164] The embodiment of the cleaning step D in which the substrate is cleaned using the collected waste cleaning liquid is the same as that described for the cleaning step B. There are no particular limitations on the means for collecting the effluent in the effluent collection steps C and E. The collected effluent is preferably stored in the container described above in the static elimination step J, and at this time, a static elimination step similar to that in the static elimination step J may be carried out. In addition, a step of filtering the collected effluent to remove impurities may be provided. [Example]

[0165] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment details, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the examples shown below.

[0166] [Examples 1 to 26, Comparative Examples 1 to 5] [Preparation of cleaning solution] Each cleaning solution of the Examples and Comparative Examples was prepared by preparing the components shown in Table 1, adding and mixing them in the blending ratios shown in Table 1, and adding hydrochloric acid or tetramethylammonium hydroxide (TMAH) as needed so that the pH of the cleaning solution would be the value shown in Table 1. The contents of the various components contained in each cleaning solution (all on a mass basis) are as shown in the table. The various components used in preparing each cleaning solution were all classified as semiconductor grade or equivalent high purity grade.

[0167] <Ingredients> The various components listed in Table 1 are described below.

[0168] (hydroxylamine compounds) HA: Hydroxylamine

[0169] (Component A) A-1: 2-(2-aminoethoxy)ethanol A-2: 2-(2-aminoethylamino)ethanol A-3: 2,2'-oxybis(ethylamine) A-4: Diethylenetriamine

[0170] (water) Deionized water (DIW)

[0171] (alcohol) Hexylene glycol 2-Ethoxyethanol 1,3-Butanediol Glycerol 2,4-Pentanediol

[0172] (Azole compounds) BTA: 1H-benzotriazole TTA: Tolyltriazole 1H-TA: 1H-tetrazole Irgamet 42: 2,2'-{[(4-methyl-1H-benzotriazol-1-yl)methyl]imino}bisethanol 5MBTA: 5-methyl-1H-benzotriazole

[0173] (Quaternary ammonium hydroxide) TMAH: Tetramethylammonium hydroxide BzTMAH: Benzyltrimethylammonium hydroxide TBAH: Tetrabutylammonium hydroxide

[0174] (Other ingredients) B-1: 4-methyl-1,3-pentadiene (component B) B-2: 4-methyl-3-penten-2-ol (component B) B-3: 2,4,4,6-tetramethyl-1,3-dioxane (component B) B-4: Isobutene (Component B) B-5: (E)-2-methyl-1,3-pentadiene (component B) B-6: 2,2,4-trimethyloxetane (component B) C-1: 2-aminoethanol (component C) C-2: Ethylenediamine (Component C)

[0175] [evaluation] [Cleaning performance] A laminate was prepared, consisting of a 100-nm-thick SiO2 film laminated on a Si substrate. Plasma etching was performed on this laminate using a fluorine-containing gas with a TiN metal hard mask, etching approximately 50 nm into the SiO2 film to produce a test specimen for evaluation, with a 2-cm square grid pattern. Analysis of the etched bottom surface using X-ray photoelectron spectroscopy (XPS) detected fluorine, presumably derived from dry etching residue. The dry etching residue formed by plasma etching using the fluorine-containing gas is presumed to be an organic / inorganic mixed residue incorporating Si and O from the SiO2 and C and F from the etching gas.

[0176] The cleaning performance of each cleaning solution was then evaluated according to the following procedure. A 500 mL glass beaker was filled with 200 mL of cleaning solution. While stirring using a stirrer, the temperature of the cleaning solution was raised to 65°C. Next, the test specimen prepared above was immersed in the cleaning solution at 65°C while stirring for a predetermined cleaning time, thereby cleaning the test specimen. While the test specimen was immersed in the cleaning solution, the test specimen was held using 4-inch long plastic locking tweezers so that the side of the test specimen from which the residue had been removed faced the stirrer.

[0177] After the predetermined cleaning time had elapsed, the test specimen was immediately removed from the cleaning solution and placed in 400 mL of gently stirred DI water (water temperature: 20° C.) in a 500 mL plastic beaker. After immersion in the DI water for 30 seconds, the test specimen was immediately removed and rinsed under a stream of 20° C. DI water for 30 seconds. Subsequently, the test piece was exposed to a nitrogen gas flow to blow off the droplets adhering to the surface of the test piece and dry the surface of the test piece. After this nitrogen drying step, the test piece was removed from the holding portion of the plastic tweezers, and the test piece was placed in a plastic storage box with a lid, with the element surface facing up, and stored.

[0178] The composition of the surface of the obtained test piece was analyzed using an XPS device (product name: QuanteraSXM, manufactured by Ulvac-PHI) to measure the content (atomic %) of fluorine atoms derived from dry etching residues on the surface of the test piece. For each cleaning solution, the cleaning test was carried out by changing the cleaning time in 10-second increments from 30 seconds to 300 seconds, and the shortest cleaning time at which the fluorine atom content on the surface of the test piece after cleaning was 1 atomic % or less (hereinafter referred to as the "cleaning completion time") was determined. The cleaning performance (ability to remove dry etching residues) of each cleaning solution was evaluated based on the cleaning completion time obtained, according to the following evaluation criteria. The shorter the cleaning completion time of a cleaning solution, the better the cleaning performance of that cleaning solution. The fluorine atom content on the surface of the test piece that had been subjected to the above plasma etching before cleaning was 4 to 5 atomic %.

[0179] (Cleaning performance evaluation standard) A: The cleaning time was less than 90 seconds. B: The cleaning completion time was 90 seconds or more but less than 120 seconds. C: The cleaning completion time was 120 seconds or more and less than 150 seconds. D: The cleaning completion time was between 150 seconds and 300 seconds. E: Even after 300 seconds of cleaning in the above cleaning test, the fluorine atom content on the surface of the test piece did not fall below the above reference value.

[0180] [Dissolution suppression performance] A substrate was prepared by forming a film of metallic cobalt (Co film) on one surface of a commercially available silicon wafer (diameter: 12 inches). The Co film was formed by first forming a 10-nm-thick Co film by CVD, and then forming a Co film with a total thickness of 5,000 nm by electroplating. The resulting Co film was cleaned using each of the cleaning solutions of the Examples and Comparative Examples. Specifically, the Co film was immersed in the cleaning solution of the Examples and Comparative Examples for 60 minutes, followed by two rinse treatments in which it was immersed in pure water for 15 seconds. The substrate was then dried with nitrogen gas. The dissolution rate (Å / min) was calculated based on the difference in thickness of the Co film before and after immersion in the cleaning solution.

[0181] Substrates were prepared by forming a W film (W film), a TiN film (TiN film), and an AlOx film (AlOx film) on one surface of a commercially available silicon wafer (diameter: 12 inches). The specific method for forming each film was to first form a 5 nm thick film by the ALD method, and then form a film with a total thickness of 5000 nm by the CVD method. Next, as described above, each substrate was immersed in each cleaning solution, and the dissolution rate (Å / min) of each film was measured. The dissolution suppression performance of the cleaning solution was evaluated based on the measured dissolution rate of each film.

[0182] The thickness of each film formed on the substrate was measured by the following method. The thicknesses of the Co film, W film, and TiN film were measured by X-ray fluorescence analysis (XRF) using an X-ray fluorescence analyzer ("AZX400" manufactured by Rigaku Corporation). The thickness of the AlOx film was measured using ellipsometry (spectroscopic ellipsometer, trade name "Vase", manufactured by J.A. Woollam Japan) under the conditions of a measurement range of 250-1000 nm and measurement angles of 70 degrees and 75 degrees. The measurement results are summarized in Table 1.

[0183] Table 1 below shows the composition of the cleaning solution and the evaluation results for each example and comparative example. In the table, the notation "(%)" indicates the ratio of the content of the component to the total mass of the cleaning liquid, expressed as mass %. In the table, the column "Ratio 1" indicates the ratio of the content of the hydroxylamine compound to the content of component A in each cleaning liquid (hydroxylamine compound / component A) expressed as a mass ratio. The column "cleaning solution pH" indicates the pH of each cleaning solution at 25°C measured using a pH meter.

[0184] [Table 1]

[0185] [Table 2]

[0186] From the results in Table 1, it was confirmed that the cleaning solution of the present invention is superior in the effect of the present invention to the cleaning solutions of the comparative examples.

[0187] It was confirmed that when the alcohol contained in the cleaning liquid is a polyhydric alcohol, the cleaning liquid has better dissolution suppression performance for the TiN-containing layer than when the alcohol contained in the cleaning liquid is a monoalcohol (e.g., comparison between Examples 2 and 5). It was confirmed that when the cleaning liquid contains two or more polyhydric alcohols represented by the above formula (2), the cleaning performance is more excellent (comparison between Examples 2 and 9, etc.).

[0188] It was confirmed that when the cleaning liquid contains a quaternary ammonium hydroxide, at least one of the cleaning performance and the performance of inhibiting dissolution of the Co-containing layer, the W-containing layer, and / or the TiN-containing layer is superior (e.g., comparison between Examples 1, 2, and 16 to 18). It was confirmed that when the cleaning solution contained component B, the cleaning performance was superior (comparison of Examples 1, 2, 7, 8 and 10 to 13, etc.). It was confirmed that when the cleaning solution contained component C, the cleaning performance was better (e.g., comparison of Examples 1, 24 and 25). [Explanation of symbols]

[0189] 1 board 2 metal layers 3. Etch stop layer 4 Interlayer insulating film 5 Metal Hard Mask 6 holes 10 Laminate 11 Inner wall 11a Sectional wall 11b Bottom wall 12 Dry etching residue< / ph>

Claims

1. a hydroxylamine compound, which is at least one selected from the group consisting of hydroxylamine and hydroxylamine salts; Component A represented by the following formula (1); A cleaning solution for semiconductor devices, comprising: Component A contains 2-(2-aminoethylamino)ethanol or 2,2′-oxybis(ethylamine), A cleaning solution for semiconductor devices, wherein the mass ratio of the content of the hydroxylamine compound to the content of the component A is 5 to 200. NH2-CH2CH2-X-CH2CH2-Y (1) In formula (1), X represents —NR— or —O—, R represents a hydrogen atom or a substituent, and Y represents a hydroxy group or a primary amino group.

2. The cleaning solution of claim 1 further comprising an alcohol.

3. The cleaning solution according to claim 2 , wherein the alcohol comprises a polyhydric alcohol having two or more hydroxy groups.

4. The cleaning solution according to claim 2 or 3, wherein the alcohol comprises a compound represented by the following formula (2): HO-C(R １ ) ２ -C(R ２ ) ２ -C(R ３ ) ２ -OH (2) In formula (2), R １ , R ２ and R ３ represents a hydrogen atom, a hydroxy group, or an alkyl group which may have a hydroxy group. １ , multiple R ２ and multiple R ３ may be the same or different from each other.

5. The cleaning solution according to claim 4 , wherein the alcohol contains two or more compounds represented by formula (2).

6. The cleaning solution according to any one of claims 2 to 5, wherein the alcohol comprises at least one selected from the group consisting of 1,3-propanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, glycerol, 2,4-pentanediol, 2,2-dimethyl-1,3-propanediol, and hexylene glycol.

7. A cleaning solution according to any one of claims 2 to 6, wherein the alcohol comprises hexylene glycol.

8. A hydroxylamine compound which is at least one selected from the group consisting of hydroxylamine and hydroxylamine salts; Component A represented by the following formula (1); Alcohol and A cleaning solution for semiconductor devices, comprising: the alcohol includes at least one selected from the group consisting of glycerol, 2,4-pentanediol, 2,2-dimethyl-1,3-propanediol, and hexylene glycol; A cleaning solution for semiconductor devices, wherein the mass ratio of the content of the hydroxylamine compound to the content of the component A is 5 to 200. NH 2 -CH 2 CH 2 -X-CH 2 CH 2 -Y (1) In formula (1), X represents —NR— or —O—, R represents a hydrogen atom or a substituent, and Y represents a hydroxy group or a primary amino group.

9. A cleaning solution as described in claim 8, wherein the alcohol includes hexylene glycol.

10. The cleaning solution according to any one of claims 1 to 9, wherein the content of component A is 0.1 to 1 mass % relative to the total mass of the cleaning solution.

11. The cleaning solution according to any one of claims 1 to 10, further comprising an azole compound.

12. The cleaning solution according to any one of claims 1 to 11, further comprising a quaternary ammonium hydroxide.

13. 13. The cleaning solution according to claim 12, wherein at least one of the four hydrocarbon groups substituted on the quaternary ammonium cation of the quaternary ammonium hydroxide is a hydrocarbon group having two or more carbon atoms.

14. Further comprising a component B which is at least one selected from the group consisting of isobutene, (E)-2-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2,2,4-trimethyloxetane, 4-methyl-3-penten-2-ol, and 2,4,4,6-tetramethyl-1,3-dioxane; When the cleaning solution contains one type of component B, the content of the component B relative to the total mass of the cleaning solution is 0.1 mass% or less, The cleaning solution according to any one of claims 1 to 13, wherein when the cleaning solution contains two or more types of component B, the content of each of the components B relative to the total mass of the cleaning solution is 0.1 mass% or less.

15. Further comprising component C, which is at least one selected from the group consisting of ethylenediamine and 2-aminoethanol; When the cleaning solution contains one type of component C, the content of the component C relative to the total mass of the cleaning solution is 5.0 mass% or less, The cleaning solution according to any one of claims 1 to 14, wherein when the cleaning solution contains two or more types of component C, the content of each of the components C relative to the total mass of the cleaning solution is 2.5 mass% or less.

16. The cleaning solution according to any one of claims 1 to 15, which has a pH of 8 to 14 at 25°C.

17. The cleaning solution according to any one of claims 1 to 16, which has a pH of 9 to 12 at 25°C.

18. A method for cleaning a semiconductor substrate, comprising a cleaning step of cleaning a semiconductor substrate having a metal layer with the cleaning liquid according to any one of claims 1 to 17.

19. the metal layer comprises tungsten; The cleaning step removes dry etching residues adhering to the semiconductor substrate. The method for cleaning a semiconductor substrate according to claim 18.

20. the semiconductor substrate has a layer containing cobalt or titanium nitride; The cleaning step removes dry etching residues adhering to the semiconductor substrate.

20. The method for cleaning a semiconductor substrate according to claim 18 or 19.

21. the semiconductor substrate having an etch stop layer comprised of aluminum oxide; the cleaning step removes at least a portion of the etch stop layer; The method for cleaning a semiconductor substrate according to any one of claims 18 to 20.

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