WO2021039701A1 - Treatment liquid - Google Patents

Abstract

The present invention addresses the problem of providing a treatment liquid that maintains excellent residue removal performance and corrosion prevention performance, even when repeatedly subjected to changes in thermal environment between cold storage and sitting at room temperature.　This treatment liquid includes a hydroxyamine compound selected from the group that consists of hydroxyamines and hydroxyamine salts, an organic solvent, a basic compound, and at least one type of first metal ion selected from the group that consists of Na, Al, K, Ca, Cr, Fe, Ni, and Zn. The total first metal ion content of the treatment liquid is 7.0–800.0 mass ppb relative to the total mass of the treatment liquid.

Description

Treatment liquid

The present invention relates to a treatment liquid. In particular, the present invention relates to a treatment liquid that can be suitably used for manufacturing a semiconductor device.

Semiconductor devices such as CCD (Charge-Couple Device) and memory are manufactured by forming fine electronic circuit patterns on a substrate using photolithography technology. Specifically, a resist film is formed on a laminate having a metal film as a wiring material, an etching stop layer, and an interlayer insulating layer on a substrate, and a photolithography step and a dry etching step (for example, plasma etching treatment). By carrying out the above, a semiconductor device is manufactured.

Recently, in order to realize further miniaturization of semiconductor devices, metal material-based resist films such as TiN and AlOx (so-called metal hard masks) are also used as the resist films. When a metal hard mask is used as a resist film, a dry etching process (for example, plasma etching treatment) is usually performed using the metal hard mask as a mask to form holes based on the pattern shape of the metal hard mask for wiring. A step of exposing the metal film surface to be a film is performed.

The substrate that has undergone the dry etching step contains a large amount of dry etching residue (when a metal hard mask is used as the resist film, a large amount of metal components such as titanium-based metals are contained as residue components. On the other hand, a photoresist film is used. In some cases, a large amount of organic components are contained as residual components). These residues are generally removed using a treatment liquid so as not to interfere with the next step.

For example, Patent Document 1 states that "at least selected from the group consisting of hydroxyamine and 1,8-diazabicyclo [5.4.0] undecene-7 and 1,4-diazabicyclo [2.2.2] octane. A cleaning solution for lithography containing one amine compound, a water-soluble organic solvent, and water and having a pH of 8 or more, and containing the water-soluble organic solvent in an amount of 10% by mass or more based on the total amount of the cleaning solution for lithography. A cleaning solution for lithography, which is characterized by the above, is disclosed.

Special Table No. 6486652

When the present inventors examined the time-dependent performance of the treatment liquid described in Patent Document 1, they found that the performance stability may be inferior when stored under predetermined conditions. More specifically, in general, the treatment liquid is refrigerated at a predetermined temperature when not in use, and when in use, the treatment liquid is taken out of the refrigeration storage and returned to room temperature for use. The present inventors repeatedly performed a series of operations in which the treatment liquid was refrigerated for a predetermined time and then allowed to stand at room temperature for a predetermined time, and the residue removing performance of the treatment liquid (particularly, metal hard). It has been found that the mask-derived residue removal performance) and the anticorrosion performance (particularly, the anticorrosion performance against Co (cobalt) or Co alloy) may be inferior, and the stability of these performances may be inferior.
That is, it was clarified that there is room for improving the treatment liquid so that the residual removal performance and the anticorrosion performance are ensured even if the temperature environment changes as described above. In the following, ensuring the above performance is also referred to as being excellent in performance stability of residue removing performance and anticorrosion performance.

Therefore, the present invention has a residue removing performance (particularly, a metal hard mask-derived residue removing performance) and an anticorrosion performance (particularly, an anticorrosion performance against a Co or Co alloy) even if the temperature environment changes such as refrigerated storage and room temperature standing are repeated. ), It is an object of the present invention to provide a treatment liquid having excellent performance stability.

As a result of diligent studies to solve the above problems, the present inventors have found that the above problems can be solved by the following configuration.

[1] Hydroxylamine compounds selected from the group consisting of hydroxyamines and hydroxyamine salts, and
With organic solvent
Basic compounds and
A treatment liquid containing one or more first metal ions selected from the group consisting of Na, Al, K, Ca, Cr, Fe, Ni, and Zn.
A treatment liquid in which the total content of the first metal ions is 7.0 mass ppb to 800.0 mass ppb with respect to the total mass of the treatment liquid.
[2] The content of at least one metal ion among the first metal ions contained in the treatment liquid is 1.0 mass ppb to 100.0 mass ppb with respect to the total mass of the treatment liquid. , [1].
[3] The first metal ions contained in the treatment liquid are two or more kinds, and the content of each metal ion is 1.0 mass ppb to 100. With respect to the total mass of the treatment liquid. The treatment solution according to [1] or [2], which has 0 mass ppb.
[4] Further, it contains one or more second metal ions selected from the group consisting of Li, Mg, Mn, Cu, Ag, Pb, and Co.
The treatment liquid according to any one of [1] to [3], wherein the total content of the second metal ion is 0.01 mass ppb to 10.0 mass ppb with respect to the total mass of the treatment liquid.
[5] The content of at least one metal ion among the second metal ions contained in the treatment liquid is 0.01 mass ppb to 1.0 mass ppb with respect to the total mass of the treatment liquid. , [4].
[6] The number of the second metal ions contained in the treatment liquid is two or more, and the content of each metal ion is 0.01 mass ppb to 1. with respect to the total mass of the treatment liquid. The treatment solution according to [4] or [5], which has 0 mass ppb.
[7] The treatment solution according to any one of [1] to [6], wherein the hydroxyamine compound contains at least one selected from the group consisting of hydroxyamine and hydroxyamine sulfate.

According to the present invention, it is possible to provide a treatment liquid having excellent performance stability of residue removal performance and anticorrosion performance even if the temperature environment changes such as refrigerated storage and room temperature standing are repeated.

It is sectional drawing which shows an example of the laminate applicable to the method of cleaning a substrate using the processing liquid of this invention.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, the numerical range represented by using "-" means a range including the numerical values before and after "-" as the lower limit value and the upper limit value.
Further, in the present invention, the term "preparation" includes not only synthesizing or blending a specific material to prepare the material, but also procuring a predetermined material by purchase or the like.
Further, in the present invention, "ppb" means "parts-per-parts ( ^10-9 )".
Further, in the present invention, 1 Å (angstrom) corresponds to 0.1 nm.
In addition, in the notation of groups (atomic groups) in the present invention, notations that do not describe substitutions and non-substitutions include those that do not have substituents and those that have substituents as long as the effects of the present invention are not impaired. It includes. For example, the "hydrocarbon group" includes not only a hydrocarbon group having no substituent (unsubstituted hydrocarbon group) but also a hydrocarbon group having a substituent (substituted hydrocarbon group). .. This is synonymous with each compound.
In the present specification, the pH of the treatment liquid is a value measured by F-51 (trade name) manufactured by HORIBA, Ltd. at room temperature (25 ° C.).
Further, the "radiation" in the present invention means, for example, the emission line spectrum of a mercury lamp, far ultraviolet rays typified by an excimer laser, extreme ultraviolet rays (EUV light), X-rays, electron beams, and the like. Further, in the present invention, light means active light rays or radiation. Unless otherwise specified, the term "exposure" in the present invention refers not only to exposure with far ultraviolet rays such as mercury lamps and excimer lasers, X-rays or EUV light, but also for drawing with particle beams such as electron beams or ion beams. Include in exposure.

[Treatment liquid]
The treatment liquid of the present invention is
Hydroxylamine compounds selected from the group consisting of hydroxyamines and hydroxyamine salts, and
With organic solvent
Basic compounds and
A treatment liquid containing one or more first metal ions selected from the group consisting of Na, Al, K, Ca, Cr, Fe, Ni, and Zn.
The total content of the first metal ions is 7.0 mass ppb to 800.0 mass ppb with respect to the total mass of the treatment liquid.

As a result of diligent studies, the inventors have not clarified the mechanism of action, but according to the treatment liquid having the above configuration, the performance of residue removal performance and anticorrosion performance is stable even if the temperature environment changes such as refrigerated storage and room temperature standing are repeated. It has been clarified that it has excellent properties (hereinafter, also referred to as "excellent in stability over time of residue removing performance and anticorrosion performance").
The above-mentioned treatment liquid can be applied as a treatment liquid for a semiconductor device to each process when manufacturing a semiconductor device. In particular, the treatment liquid can be suitably used as a cleaning liquid after a dry etching step using a metal hard mask as a mask.
Hereinafter, each component contained in the treatment liquid of the present invention will be described.

[Hydroxyamine compound]
The treatment liquid of the present invention contains a hydroxyamine compound selected from the group consisting of hydroxyamines and hydroxyamine salts. The hydroxyamine compound has a function of promoting decomposition and solubilization of the residue.

Here, the "hydroxyamine" according to the hydroxyamine compound of the treatment liquid of the present invention refers to a hydroxyamine compound in a broad sense including a substituted or unsubstituted alkylhydroxyamine, and any of them is the present invention. The effect of can be obtained.
The hydroxyamine compound is not particularly limited, but as a preferred embodiment, an unsubstituted hydroxyamine and a hydroxyamine derivative, and a salt thereof are preferable.

The hydroxyamine derivative is not particularly limited, but for example, O-methylhydroxyamine, O-ethylhydroxyamine, N-methylhydroxyamine, N, N-dimethylhydroxyamine, N, O-dimethylhydroxyamine, N-ethylhydroxy. Amin, N, N-diethylhydroxyamine, N, O-diethylhydroxyamine, O, N, N-trimethylhydroxyamine, N, N-dicarboxyethyl hydroxyamine, N, N-disulfoethyl hydroxyamine, etc. Can be mentioned.

As the salt of the unsubstituted hydroxyamine or the hydroxyamine derivative, the inorganic acid salt or the organic acid salt of the above-mentioned unsubstituted hydroxyamine or the hydroxyamine derivative is preferable, and a non-metal atom such as Cl, S, N, or P is a hydrogen atom. A salt of an inorganic acid formed by binding with is more preferable, and a salt of any of hydrochloric acid, sulfuric acid, and nitric acid is further preferable. Among them, hydroxyamine nitrate (hydroxyamine nitrate), hydroxyamine sulfate (hydroxyamine sulfate), hydroxyamine hydrochloride, hydroxyamine phosphate, N, N-diethylhydroxyamine sulfate, N, N-diethylhydroxyamine nitrate, or A mixture of these is preferred.
In addition, examples of the above-mentioned organic acid salt of the unsubstituted hydroxyamine or the hydroxyamine derivative include hydroxyammonium citrate, hydroxyammonium oxalate, and hydroxyammonium fluoride.

As the hydroxyamine compound, at least one hydroxyamine compound selected from the group consisting of hydroxyamine and hydroxyamine sulfate is preferable in that the residue removing performance of the treatment liquid and the anticorrosion performance over time are more excellent. Unsubstituted hydroxyamines and sulfates thereof are more preferred, and unsubstituted hydroxyamines are even more preferred.

The lower limit of the content of the hydroxyamine compound is preferably 0.1% by mass or more with respect to the total mass of the treatment liquid, and is 1% by mass or more in that the residue removal property and defect suppression property of the treatment liquid are more excellent. Is more preferable, and 3% by mass or more is further preferable. The upper limit of the content of the hydroxyamine compound is preferably 40% by mass or less, more preferably 30% by mass or less, and 25% by mass, because the anticorrosion performance of the treatment liquid is more excellent with respect to the total mass of the treatment liquid. The following is more preferable, 20% by mass or less is particularly preferable, and 15% by mass or less is most preferable.
The hydroxyamine compound may be used alone or in combination of two or more. When two or more types are used, the total content thereof is preferably within the above range.

[Basic compound]
The treatment liquid of the present invention contains a basic compound. The "basic compound" referred to here and the above-mentioned hydroxyamine compound are different compounds. That is, the hydroxyamine compound is not included in the basic compound.
The basic compound may be either an inorganic base compound or an organic base compound, but an organic basic compound is preferable in that the treatment liquid has more excellent residue removing property and defect suppressing property, and an amine compound or a nitrogen-containing compound is preferable. Aromatic compounds are more preferred.

As the amine compound, it is possible to more effectively suppress the corrosion of the metal layer (preferably the metal layer containing W (tungsten) and / or Co (cobalt)) on the substrate while ensuring the residue removing performance. Therefore, an amine compound having a cyclic structure is preferable.
In the amine compound having a cyclic structure, the amino group may be present in only one of the cyclic structure and the outside of the cyclic structure, or may be present in both. However, when the amino group is a tertiary amino group, the tertiary amino group is present in the cyclic structure, and the cyclic structure is a non-aromatic cyclic structure (nitrogen-containing non-aromatic ring). preferable.
Examples of the amine compound include tetrahydrofurfurylamine, N- (2-aminoethyl) piperazine, 1,8-diazabicyclo [5.4.0] -7-undecene (DBU), and 1,4-diazabicyclo [2.2]. .2] Octane, hydroxyethylpiperazine, piperazine, 2-methylpiperazine, trans-2,5-dimethylpiperazine, cis-2,6-dimethylpiperazine, 2-piperidinemethanol, cyclohexylamine, 1,5-diazabicyclo [4, 3,0] -5-nonene, diethylenetriamine, triethylenetetramine, tetraethylenepentamine and the like can be mentioned.
Among them, tetrahydrofurfurylamine and N are used as amine compounds from the viewpoint of more effectively suppressing the corrosion of the metal layer (preferably the metal layer containing Co or Co alloy) on the substrate while ensuring the residue removing performance. -(2-Aminoethyl) piperazin, 1,8-diazabicyclo [5.4.0] -7-undecene, or 1,4-diazabicyclo [2.2.2] octane is preferred.
The molecular weight of the amine compound is preferably 50 to 500, more preferably 75 to 400, and even more preferably 100 to 300.

The nitrogen-containing aromatic compound is not particularly limited, and for example, substituted or unsubstituted benzotriazole is preferable. As the substituted benzotriazole, for example, a benzotriazole substituted with an alkyl group or an aryl group is preferable.
Specific examples of the substituted or unsubstituted benzotriazole include benzotriazole (BTA) and 5-methyl-1H-benzotriazole (5M-BTA).

The basic compound may be used alone or in combination of two or more.
The content of the basic compound (the total content when two or more kinds are used) is, for example, 0.1 to 20% by mass and 0.5 to 15% by mass with respect to the total mass of the treatment liquid. preferable.

[Organic solvent]
The treatment liquid of the present invention contains an organic solvent.
The organic solvent is not particularly limited, but an alcohol solvent is preferable, and a water-soluble alcohol solvent is more preferable.
Examples of the alcohol-based solvent include alkanediols, alkylene glycols, alkoxy alcohols, saturated aliphatic monohydric alcohols, unsaturated non-aromatic monohydric alcohols, and trihydric or higher alcohols.

Examples of the alkanediol include glycol, 2-methyl-1,3-propanediol, 1,2-propanezyl, 1,3-dihydroxypropane, 2-methylpentane-2,4-diol, and 2,2-dimethyl. -1,3-Hexanediol, 1,4-dihydroxybutane, 1,3-butanediol, 1,2-butanediol, 2,3-butanediol, 2,5-dihydroxy-2,5-dimethylhexane, pinacol , And alkylene glycol and the like.

Examples of the alkylene glycol include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol and the like.

Examples of the alkoxy alcohol include 3-methoxy-1-butanol, 3-methoxy-3-methylbutanol, 1-methoxy-2-butanol, glycol monoether and the like.

Examples of the glycol monoether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monon-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (EGBE), diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. Diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, 1-methoxy-2-propanol, 2-methoxy-1-propanol, 1-ethoxy-2-propanol, 2-ethoxy -1-propanol, propylene glycol mono-n-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, Examples thereof include ethylene glycol monobenzyl ether and diethylene glycol monobenzyl ether.

Saturated aliphatic monohydric alcohols include, for example, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 2-pentanol, t-pentyl alcohol, and 1-Hexanol and the like can be mentioned.

Examples of unsaturated non-aromatic monohydric alcohols include allyl alcohol, propargyl alcohol, 2-butenyl alcohol, 3-butenyl alcohol, 4-pentene-2-ol and the like.

Examples of low molecular weight alcohols containing a ring structure include tetrahydrofurfuryl alcohol, furfuryl alcohol, and 1,3-cyclopentanediol.

Examples of trihydric or higher alcohols include glycerin and the like.

Among them, as the organic solvent, alkanediol (preferably 2-methylpentane-2,4-diol), alkoxyalcohol (preferably 3-methoxy-3-methylbutanol), or glycol monoether (preferably, preferably) EGBE) is preferred.

The molecular weight of the organic solvent is preferably 32 to 250, more preferably 40 to 200, and even more preferably 50 to 150.

The lower limit of the content of the organic solvent is preferably 1% by mass or more with respect to the total mass of the treatment liquid, and more preferably 2% by mass or more in that the residue removal performance and the anticorrosion performance are more excellent over time. .. The upper limit of the content of the organic solvent is preferably 40% by mass or less with respect to the total mass of the treatment liquid, and more preferably 30% by mass or less in that the residue removal performance and the anticorrosion performance are more excellent over time. , 25% by mass or less is more preferable.
The organic solvent may be used alone or in combination of two or more. When two or more types are used, the total content thereof is preferably within the above range.

[First metal ion]
The treatment liquid of the present invention contains one or more first metal ions selected from the group consisting of Na, Al, K, Ca, Cr, Fe, Ni, and Zn.
The lower limit of the total content of the first metal ions in the treatment liquid of the present invention is 7.0 mass ppb or more with respect to the total mass of the treatment liquid, and the stability over time of the residue removal performance and the anticorrosion performance is good. In terms of superiority, 8.0 mass ppb or more is preferable, and 9.0 mass ppb or more is more preferable. Further, the upper limit of the total content of the first metal ion is 800.0 mass ppb or less with respect to the total mass of the treatment liquid, and 700 in that the residue removal performance and the anticorrosion performance are more excellent over time. It is preferably 0.0 mass ppb or less, and more preferably 600.0 mass ppb or less.

The content of at least one metal ion among the first metal ions contained in the treatment liquid is 1. With respect to the total mass of the treatment liquid, in that the residue removal performance and the anticorrosion performance are more excellent over time. It is preferably 0 to 100.0 mass ppb.

In that the residue removal performance and the anticorrosion performance are more excellent over time, the treatment liquid contains two or more first metal ions, and the content of each metal ion is the total mass of the treatment liquid. It is preferably 1.0 to 100.0 mass ppb, and the treatment liquid is all selected from the group consisting of Na, Al, K, Ca, Cr, Fe, Ni, and Zn as the first metal ion. It is more preferable that the metal ions of the above are contained and the content of each metal ion is 1.0 to 100.0 mass ppb with respect to the total mass of the treatment liquid.

It is preferable that the treatment liquid contains at least Ca ion as the first metal ion in that the residue removal performance and the anticorrosion performance are more excellent over time.

The first metal ion may be a metal ion inevitably contained in each component (raw material) contained in the treatment liquid, or a metal ion inevitably contained in the production, storage, and / or transfer of the treatment liquid. It may be added intentionally.
Examples of the method of intentionally adding the first metal ion to the system include a method of adding a metal salt containing the corresponding metal atom. The type of the metal salt is not particularly limited, and examples thereof include sulfates, chloride salts, and bromide salts.

The type and content of metal ions in the treatment liquid can be measured by the SP-ICP-MS method (Single Nano Particile Inductively Coupled Plasma Mass Spectrometry).
Here, the SP-ICP-MS method uses the same apparatus as the ordinary ICP-MS method (inductively coupled plasma mass spectrometry), and differs only in data analysis. Data analysis of the SP-ICP-MS method can be performed by commercially available software.
In the ICP-MS method, the content of the metal component to be measured is measured regardless of its existence form. Therefore, the total mass of the metal particles and the metal ions to be measured is quantified as the content of the metal component.

On the other hand, in the SP-ICP-MS method, the content of metal particles can be measured. Therefore, the content of metal ions in the sample can be calculated by subtracting the content of the metal particles from the content of the metal component in the sample.
Examples of the device for the SP-ICP-MS method include an Agilent 8800 triple quadrupole ICP-MS (inductively coupled plasma mass spectrometery, option # 200) manufactured by Agilent Technologies, Inc., which is described in Examples. It can be measured by the above method. As other devices other than the above, in addition to the NexION 350S manufactured by PerkinElmer, the Agilent 8900 manufactured by Agilent Technologies can also be used.

〔water〕
The treatment liquid of the present invention preferably further contains water.
The content of water in the treatment liquid of the present invention is not particularly limited, and is preferably 15 to 98% by mass, more preferably 30 to 95% by mass, and further 50 to 95% by mass with respect to the total mass of the treatment liquid. preferable.

[Second metal ion]
The treatment liquid of the present invention preferably further contains a second metal ion.
The second metal ion is one or more metal ions selected from the group consisting of Li, Mg, Mn, Cu, Ag, Pb, and Co.
The lower limit of the total content of the second metal ion in the treatment liquid of the present invention is preferably 0.01 mass ppb or more with respect to the total mass of the treatment liquid, and the stability over time of the residue removal performance and the anticorrosion performance is good. In terms of superiority, 0.05 mass ppb or more is more preferable, and 0.1 mass ppb or more is further preferable. Further, the upper limit of the total content of the second metal ion is preferably 10.0 mass ppb or less with respect to the total mass of the treatment liquid, and the residue removal performance and the anticorrosion performance are more excellent over time. It is more preferably 0.0 mass ppb or less, and further preferably 6.0 mass ppb or less.

The content of at least one metal ion among the second metal ions contained in the treatment liquid is 0, based on the total mass of the treatment liquid, in that the residue removal performance and the anticorrosion performance are more excellent over time. It is preferably 01 to 1.0 mass ppb.

In that the residue removal performance and the anticorrosion performance are more excellent over time, the treatment liquid contains two or more types of second metal ions, and the content of each metal ion is the total mass of the treatment liquid. It is preferably 0.01 to 1.0 mass ppb, and all metals selected from the group consisting of Li, Mg, Mn, Cu, Ag, Pb, and Co as the second metal ion in the treatment liquid. More preferably, it contains ions and the content of each metal ion is 0.01 to 1.0 mass ppb with respect to the total mass of the treatment liquid.

The second metal ion may be a metal ion inevitably contained in each component (raw material) contained in the treatment liquid, or a metal ion inevitably contained in the production, storage, and / or transfer of the treatment liquid. It may be added intentionally.
Examples of the method of intentionally adding the second metal ion to the system include a method of adding a metal salt containing the corresponding metal atom. The type of the metal salt is not particularly limited, and examples thereof include sulfates, chloride salts, and bromide salts.

The method for measuring the content of the second metal ion in the treatment liquid is the same as the method for measuring the content of the first metal ion described above.

[Chelating agent]
The treatment liquid of the present invention preferably further contains a chelating agent. The chelating agent chelate with the oxidized metal contained in the residue.
The chelating agent is not particularly limited, but a polyaminopolycarboxylic acid is preferable.
A polyaminopolycarboxylic acid is a compound having a plurality of amino groups and a plurality of carboxylic acid groups. Examples of the polyaminopolycarboxylic acid include mono- or polyalkylene polyamine polycarboxylic acids, polyaminoalkane polycarboxylic acids, polyaminoalkanol polycarboxylic acids, and hydroxyalkyl ether polyamine polycarboxylic acids.

Examples of the polyaminopolycarboxylic acid include butylenediaminetetraacetic acid, diethylenetriaminetetraacetic acid (DTPA), ethylenediaminetetrapropionic acid, triethylenetetraminehexacetic acid, 1,3-diamino-2-hydroxypropane-N, N, N', N'-tetraacetic acid, propylenediaminetetraacetic acid, ethylenediaminetetraacetic acid (EDTA), trans-1,2-diaminocyclohexanetetraacetic acid, ethylenediaminediaminetetraacetic acid, ethylenediaminediaminedipropionic acid, 1,6-hexamethylene-diamine-N, N , N', N'-tetraacetic acid, N, N-bis (2-hydroxybenzyl) ethylenediamine-N, N-diacetate, diaminopropanetetraacetic acid, 1,4,7,10-tetraazacyclododecane-4acetic acid , Diaminopropanol tetraacetic acid, (hydroxyethyl) ethylenediaminetetraacetic acid and the like. Of these, diethylenetriaminepentacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), or trans-1,2-diaminocyclohexanetetraacetic acid is preferable.

The content of the chelating agent in the treatment liquid of the present invention is not particularly limited, and is preferably 0.01 to 5% by mass, more preferably 0.01 to 3% by mass, based on the total mass of the treatment liquid.
The chelating agent may be used alone or in combination of two or more. When two or more types are used, the total content thereof is preferably within the above range.

[Other ingredients]
The treatment liquid of the present invention may further contain other components other than the above-mentioned components.
Examples of other components include surfactants, quaternary ammonium hydroxide salts, reducing agents, pH adjusting agents, foodstuff-proofing agents, defoaming agents, rust-preventing agents, preservatives and the like.

[PH of treatment solution]
The pH of the treatment liquid of the present invention is not particularly limited, but it is preferably in the alkaline region because it is excellent in residue removing performance. Among them, the pH of the treatment liquid is preferably 8 or more, more preferably 9 or more, still more preferably 10 or more, in that the anticorrosion performance against Co is more excellent. The pH of the treatment liquid is preferably 14 or less, more preferably 12 or less, in that the anticorrosion performance against W is more excellent.
In order to prepare the treatment liquid in the above pH range, the treatment liquid may further contain a pH adjusting agent.

[Use]
The treatment liquid of the present invention can be suitably used as a treatment liquid for semiconductor devices. In the present invention, "for semiconductor devices" means that it is used in the manufacture of semiconductor devices. The treatment liquid of the present invention can be used in any step for manufacturing a semiconductor device, for example, treatment of an insulating film, a resist or an antireflection film existing on a substrate, a dry etching residue (resist of a photoresist film and a residue of a photoresist film). It can be used for the treatment of metal hard mask residues, etc.) and the treatment of ashing residues.
As a more specific use of the treatment liquid, it is applied on a substrate to improve the coatability of the composition before the step of forming a photoresist film using the sensitive light-sensitive or radiation-sensitive resin composition. A pre-wet solution, a cleaning solution used for removing residues such as dry etching residues, and a solution (for example, a removing solution and a stripping solution) used for removing various resist films (preferably photoresist films) used for pattern formation. Etc.), and a solution (for example, a removing solution and a stripping solution) used for removing a permanent film (for example, a color filter, a transparent insulating film, a resin lens) or the like from a substrate. It can also be used as a developing solution for various sensitive light-sensitive or radiation-sensitive resin composition layers for pattern formation.
It can also be used as a cleaning liquid used for removing residues such as metal impurities or fine particles from a substrate after chemical mechanical polishing. Since the substrate after removing the permanent film may be used again for the semiconductor device, the removal of the permanent film shall be included in the manufacturing process of the semiconductor device.
It may be used as an etching solution for treating the metal layer of a substrate having a metal layer.
Among the above applications, for removing residues such as metal impurities or fine particles from a cleaning liquid for removing dry etching residues, a solution for removing various resist films used for pattern formation, or a substrate after chemical mechanical polishing. It can be suitably used as a cleaning liquid to be used.
The treatment liquid of the present invention may be used for only one of the above-mentioned uses, or may be used for two or more uses.

In recent years, as semiconductor devices have become finer and more sophisticated, metals with higher conductivity are required as metals used for wiring materials, plug materials, and the like. For example, it is expected that the metal used as a wiring material will be replaced with Co from Al (aluminum) and Cu (copper). As for the metal used as the plug material, it is expected that the demand for Co will increase further in addition to W.
Therefore, as a characteristic of the treatment liquid, it is preferable that there is little corrosion against W and Co.
The treatment liquid of the present invention is preferably used for treating a substrate having a metal layer containing at least one selected from the group consisting of W and Co. Further, the treatment liquid of the present invention is preferably used as a treatment liquid for producing a semiconductor device including a substrate having a metal layer containing at least one selected from the group consisting of W and Co.
The metal layer containing at least one selected from the group consisting of W and / or Co may be a metal layer containing only W and / or Co, and is an alloy containing W and / or Co. It may be a metal layer of another form containing W and / or Co.

[Manufacturing method of treatment liquid]
[Method of preparing the treatment liquid]
The treatment liquid can be produced by a known method. Hereinafter, the method for producing the above-mentioned treatment liquid will be described in detail.

<Raw material refining process>
In the production of the above-mentioned treatment liquid, it is desirable to purify any one or more of the raw materials for preparing the treatment liquid in advance by distillation, ion exchange, filtration or the like. As for the degree of purification, for example, it is preferable to purify the raw material to a purity of 99% or more, and more preferably to a purity of 99.9% or more.

The purification method is not particularly limited, and examples thereof include a method of passing through an ion exchange resin or an RO membrane (Reverse Osmosis Membrane), distillation, or a method such as filtering described later. Specifically, for example, after passing the liquid through a reverse osmosis membrane or the like for primary purification, the liquid is passed through a purification device made of a cation exchange resin, an anion exchange resin, or a mixed bed type ion exchange resin to perform secondary purification. Examples thereof include a method for carrying out purification.
The purification treatment may be carried out by combining a plurality of the above-mentioned known purification methods.
Moreover, the purification treatment may be carried out a plurality of times.

<Filtering>
The filter is not particularly limited as long as it has been conventionally used for filtration. For example, fluororesins such as polytetrafluoroethylene (PTFE) and tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA), polyamide resins such as nylon, and polyolefin resins such as polyethylene and polypropylene (PP) (high density). Alternatively, a filter based on (including ultrahigh molecular weight) or the like can be mentioned. Among these materials, a material selected from the group consisting of fluororesins such as polyethylene, polypropylene (including high-density polypropylene), PTFE and PFA, and polyamide-based resins such as nylon is preferable, and among them, fluororesins such as PTFE and PFA are preferable. Resin filters are more preferred. By using a filter formed of these materials, it is possible to effectively remove highly polar foreign substances that are likely to cause defects.

The critical surface tension of the filter is preferably 70 mN / m or more, more preferably 95 mN / m or less, and even more preferably 75 to 85 mN / m. The value of the critical surface tension is the nominal value of the manufacturer. By using a filter having a critical surface tension in the above range, it is possible to effectively remove highly polar foreign substances that are likely to cause defects.

The pore diameter of the filter is preferably about 2 to 20 nm, more preferably 2 to 15 nm. Within this range, it is possible to reliably remove fine foreign substances such as impurities or agglomerates contained in the raw material while suppressing filtration clogging.

When using filters, different filters may be combined. At that time, the filtering by the first filter may be performed only once or twice or more. When filtering is performed twice or more by combining different filters, it is preferable that the pore diameters of the second and subsequent times are the same or smaller than the pore diameter of the first filtering. Further, first filters having different pore diameters within the above-mentioned range may be combined. For the hole diameter here, the nominal value of the filter manufacturer can be referred to. As a commercially available filter, for example, it can be selected from various filters provided by Nippon Pole Co., Ltd., Advantech Toyo Co., Ltd., Japan Entegris Co., Ltd. (formerly Nippon Microlith Co., Ltd.), KITZ Micro Filter Co., Ltd., and the like. In addition, "P-nylon filter (pore diameter 0.02 μm, critical surface tension 77 mN / m)" made of polyamide; (manufactured by Nippon Pole Co., Ltd.), "PE clean filter (pore diameter 0.02 μm)" made of high-density polyethylene; (Manufactured by Nippon Pole Co., Ltd.) and "PE / Clean Filter (hole diameter 0.01 μm)" made of high-density polyethylene; (manufactured by Nippon Pole Co., Ltd.) can also be used.
As the second filter, a filter formed of the same material as the first filter described above can be used. The pore size of the second filter is preferably about 1 to 10 nm.

Further, in the present invention, the temperature at which the filtering step is performed is preferably room temperature (25 ° C.) or lower, more preferably 23 ° C. or lower, and even more preferably 20 ° C. or lower. Further, 0 ° C. or higher is preferable, 5 ° C. or higher is more preferable, and 10 ° C. or higher is further preferable.

In the filtering step, particulate foreign matter or impurities can be removed, but at the above temperature, the amount of the particulate foreign matter and / or impurities dissolved in the raw material is reduced, so that filtering is more efficient. Will be removed.

In addition, in order to adjust the content of metal ions in the finally obtained treatment liquid within the range as described above, a certain amount of metal ions remain in some or all of the raw materials and their mixture. The purification treatment may be carried out by adjusting to.

<Liquid preparation process>
The preparation of the treatment liquid of the present invention is not particularly limited, and can be produced, for example, by mixing the above-mentioned components. The order and / or timing of mixing each of the above-mentioned components is not particularly limited, and examples thereof include a method in which a hydroxyamine compound is dispersed in advance in pH-adjusted water and predetermined components are sequentially mixed.

[Kit and concentrate]
The treatment liquid in the present invention may be a kit obtained by dividing the raw material into a plurality of parts.
As a specific method using the treatment liquid as a kit, for example, a liquid composition in which a hydroxyamine compound and a basic compound are dispersed or dissolved in an organic solvent is prepared as the first liquid, and the first metal ion is prepared as the second liquid. , A mode of preparing a liquid composition containing a second metal ion, and other components.
Further, the treatment liquid may be prepared by using a concentrated liquid. When a concentrated solution of the treatment liquid is prepared, the concentration ratio thereof is appropriately determined depending on the composition of the composition, but is preferably 5 to 2000 times. That is, the treatment liquid may be used by diluting the concentrated liquid 5 to 2000 times.

[Container (container)]
The treatment liquid of the present invention can be filled in an arbitrary container, stored, transported, and used as long as corrosiveness or the like is not a problem (whether it is a kit or a concentrated liquid or not). As the container, it is preferable that the container has a high degree of cleanliness and less elution of impurities for semiconductor applications. Examples of usable containers include, but are not limited to, the "clean bottle" series manufactured by Aicello Chemical Corporation and the "pure bottle" manufactured by Kodama Resin Industry. The inner wall of this container is made of one or more resins selected from the group consisting of polyethylene resin, polypropylene resin, and polyethylene-polypropylene resin, or a resin different from this, or stainless steel, hasteroi, inconel, monel, etc. It is preferably formed from a metal that has been subjected to rust and metal elution prevention treatment.

As the above-mentioned different resins, a fluororesin (perfluororesin) is preferable. In this way, by using a container whose inner wall is a fluororesin, a problem of elution of ethylene or propylene oligomer occurs as compared with a container whose inner wall is polyethylene resin, polypropylene resin, or polyethylene-polypropylene resin. Can be suppressed.
Specific examples of such a container in which the inner wall is a fluororesin include a FluoroPure PFA composite drum manufactured by Entegris. In addition, it is described on pages 4 of JP-A-3-502677, page 3 of the pamphlet of International Publication No. 2004/016526, and pages 9 and 16 of the pamphlet of International Publication No. 99/046309. Containers can also be used.

Further, in addition to the above-mentioned fluororesin, quartz and an electropolished metal material (that is, an electropolished metal material) are also preferably used for the inner wall of the container.
The metal material used for producing the electropolished metal material includes at least one selected from the group consisting of chromium and nickel, and the total content of chromium and nickel is 25 with respect to the total mass of the metal material. Metallic materials having a mass% of more than% are preferable, and examples thereof include stainless steel and nickel-chromium alloys.
The total content of chromium and nickel in the metal material is more preferably 30% by mass or more with respect to 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% by mass or less.

The stainless steel is not particularly limited, and known stainless steel can be used. Among them, an alloy containing 8% by mass or more of nickel is preferable, and an austenitic stainless steel containing 8% by mass or more of nickel is more preferable. 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), and SUS316 ( Ni content 10% by mass, Cr content 16% by mass), SUS316L (Ni content 12% by mass, Cr content 16% by mass) and the like.

The nickel-chromium alloy is not particularly limited, and a known nickel-chromium alloy can be used. Of these, nickel-chromium alloys having a nickel content of 40 to 75% by mass and a chromium content of 1 to 30% by mass are preferable.
Examples of the nickel-chromium alloy include Hastelloy (trade name, the same shall apply hereinafter), Monel (trade name, the same shall apply hereinafter), Inconel (trade name, the same shall apply hereinafter) and the like. More specifically, Hastelloy C-276 (Ni content 63% by mass, Cr content 16% by mass), Hastelloy-C (Ni content 60% by mass, Cr content 17% by mass), and Hastelloy C-22. (Ni content 61% by mass, Cr content 22% by mass) and the like.
Further, the nickel-chromium alloy may further contain boron, silicon, tungsten, molybdenum, copper, cobalt and the like, if necessary, in addition to the above alloys.

The method for electropolishing a metal material is not particularly limited, and a known method can be used. For example, the methods described in paragraphs [0011]-[0014] of JP2015-227501 and paragraphs [0036]-[0042] of JP2008-264929 can be used.

It is presumed that the content of chromium in the passivation layer on the surface of the metal material is higher than the content of chromium in the matrix by electropolishing. Therefore, it is presumed that the treatment liquid having a reduced amount of metal impurities can be obtained because the metal element does not easily flow out into the treatment liquid from the inner wall coated with the electropolished metal material.
The metal material is preferably buffed. The method of buffing is not particularly limited, and a known method can be used. The size of the abrasive grains used for finishing the buffing is not particularly limited, but # 400 or less is preferable because the unevenness on the surface of the metal material tends to be smaller.
The buffing is preferably performed before the electrolytic polishing.
Further, the metal material may be processed by combining one or more of a plurality of stages of buffing, acid cleaning, magnetic fluid polishing, etc., which are performed by changing the count such as the size of abrasive grains. ..

In the present invention, a container having the container and the treatment liquid contained in the container may be referred to as a treatment liquid container.

It is preferable that the inside of these containers is cleaned before filling with the treatment liquid. The liquid used for cleaning preferably has a reduced amount of metal impurities in the liquid. The treatment liquid of the present invention may be bottling, transported and stored in a container such as a gallon bottle or a coated bottle after production.

For the purpose of preventing changes in the components in the treatment liquid during storage, the inside of the container may be replaced with an inert gas (chisso, argon, etc.) having a purity of 99.99995% by volume or more. In particular, a gas having a low water content is preferable. Further, during transportation and storage, the temperature may be at room temperature, but in order to prevent deterioration, the temperature may be controlled in the range of −20 ° C. to 20 ° C.

[Clean room]
It is preferable that the production of the treatment liquid of the present invention, the opening and / or cleaning of the storage container, the handling including the filling of the treatment liquid, the treatment analysis, and the measurement are all performed in a clean room. The clean room preferably meets the 14644-1 clean room standard. It is preferable to satisfy 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 ISO class 1 is satisfied. Is more preferable.

[How to clean the board]
As one aspect of the substrate cleaning method using the treatment liquid of the present invention, the treatment liquid is used to clean a substrate having a metal layer containing one or more selected from the group consisting of W and Co. An embodiment having a cleaning step (hereinafter, also referred to as “cleaning step B”) can be mentioned. Further, the cleaning method of the above aspect may include a treatment liquid preparation step (hereinafter referred to as "treatment liquid preparation step A") for preparing the treatment liquid before the cleaning step B.
In the following description of the substrate cleaning method, a case where the treatment liquid preparation step A is performed before the cleaning step B is shown as an example, but the present invention is not limited to this, and the substrate cleaning method of the present invention is prepared in advance. It may be carried out by using the above-mentioned treatment liquid.

[Object to be cleaned]
The object to be cleaned in the method for cleaning a substrate of the present invention is preferably a substrate having a metal layer containing at least one selected from the group consisting of W and Co. The object to be cleaned in the method for cleaning the substrate of the present invention is, for example, a metal layer containing at least one selected from the group consisting of W and Co on the substrate (hereinafter, simply referred to as “metal layer”). , Laminates provided with an interlayer insulating layer and a metal hard mask at least in this order. The laminate further has holes formed from the surface (opening) of the metal hard mask toward the substrate so as to expose the surface of the metal layer by undergoing a dry etching process or the like.
The method for producing a laminate having holes as described above is not particularly limited, but usually, for a pretreated laminate having a substrate, a metal layer, an interlayer insulating layer, and a metal hard mask in this order, A method of performing a dry etching process using a metal hard mask as a mask and etching the interlayer insulating layer so that the surface of the metal layer is exposed to provide holes penetrating the inside of the metal hard mask and the interlayer insulating layer. Can be mentioned.
The method for producing the metal hard mask is not particularly limited. For example, first, a metal layer containing a predetermined component is formed on the interlayer insulating layer, and a resist film having a predetermined pattern is formed on the metal layer. Next, there is a method of manufacturing a metal hard mask (that is, a film in which a metal layer is patterned) by etching a metal layer using a resist film as a mask.
Further, the laminate may have a layer other than the above-mentioned layer, and examples thereof include an etching stop layer and an antireflection layer.

FIG. 1 shows a schematic cross-sectional view showing an example of a laminate that is a cleaning target of the substrate cleaning method of the present invention.
The laminate 10 shown in FIG. 1 is provided with a metal layer 2, an etching stop layer 3, an interlayer insulation layer 4, and a metal hard mask 5 in this order on a substrate 1, and is metal at a predetermined position after undergoing a dry etching process or the like. A hole 6 is formed in which the layer 2 is exposed. That is, the object to be cleaned shown in FIG. 1 includes a substrate 1, a metal layer 2, an etching stop layer 3, an interlayer insulating layer 4, and a metal hard mask 5 in this order, and an opening of the metal hard mask 5. A laminate having holes 6 penetrating from its surface to the surface of the metal layer 2 at the position of. The inner wall 11 of the hole 6 is composed of a cross-sectional wall 11a made of an etching stop layer 3, an interlayer insulating layer 4 and a metal hard mask 5, and a bottom wall 11b made of an exposed metal layer 2, to which a dry etching residue 12 adheres. doing.

The substrate cleaning method of the present invention can be suitably used for cleaning for the purpose of removing these dry etching residues 12. That is, while being excellent in removing the dry etching residue 12, it is also excellent in anticorrosion performance against the inner wall 11 (for example, the metal layer 2 and the like) of the object to be cleaned.
Further, the method for cleaning the substrate of the present invention may be carried out on a laminate in which a dry ashing step is performed after the dry etching step.
Hereinafter, each layer constituent material of the above-mentioned laminate will be described.

<Metal hard mask>
The metal hard mask preferably contains at least one component selected from the group consisting of Cu, Co, W, AlOx, AlN, AlOxNy, WOx, Ti, TiN, ZrOx, HfOx and TaOx. Here, x and y are numbers represented by x = 1 to 3 and y = 1 to 2, respectively.
Examples of the material of the metal hard mask include TiN, WO ₂ and ZrO ₂ .

<Interlayer insulation layer>
The material of the interlayer insulating layer is not particularly limited, and a material having a dielectric constant k of 3.0 or less is preferable, and a material having a dielectric constant k of 2.6 or less is more preferable.
Specific examples of the material of the interlayer insulating layer include SiO ₂ , SiOC materials, and organic polymers such as polyimide.

<Etching stop layer>
The material of the etching stop layer is not particularly limited. Specific examples of the etching stop layer material include SiN, SiON, SiOCN-based materials, and metal oxides such as AlOx.

<Metal layer>
The wiring material forming the metal layer contains at least W (tungsten) or Co (cobalt). Further, these metals may be alloys with other metals.
The wiring material of the present invention may further contain a metal other than W and Co, a metal nitride or an alloy. Specific examples thereof include copper, titanium, titanium-tungsten, titanium nitride, tantalum, tantalum compounds, chromium, chromium oxide, and aluminum.

<Board>
The "substrate" here includes, for example, a semiconductor substrate made of a single layer and a semiconductor substrate made of multiple layers.
The material constituting the semiconductor substrate composed of a single layer is not particularly limited, and is generally preferably composed of a Group III-V compound such as silicon, silicon germanium, or GaAs, or any combination thereof.
In the case of a semiconductor substrate composed of multiple layers, the configuration is not particularly limited, and for example, an interconnect structure (interconnect features) such as a metal wire and a dielectric material is exposed and integrated on the above-mentioned semiconductor substrate such as silicon. It may have a circuit structure. Metals and alloys used in interconnect structures include, but are limited to, aluminum, aluminum alloyed with copper, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, and tungsten. It's not a thing. Further, a layer such as an interlayer dielectric layer, silicon oxide, silicon nitride, silicon carbide, and carbon-doped silicon oxide may be provided on the semiconductor substrate.

[Processing process]
Hereinafter, the treatment liquid preparation step A and the cleaning step B will be described in detail.

<Treatment liquid preparation step A>
The treatment liquid preparation step A is a step of preparing the treatment liquid. Each component used in this step is as described above.
The procedure of this step is not particularly limited, and for example, a hydroxyamine compound, a basic compound, an organic solvent, a first metal ion, and other optional components are added and mixed by stirring to prepare a treatment liquid. The method of preparation is mentioned. When each component is added, it may be added all at once, or it may be added in multiple portions.
In addition, as each component contained in the treatment liquid, one classified as a semiconductor grade or one classified as a high-purity grade equivalent thereto is used to remove foreign substances by filtering and / or reduce ion components by ion exchange resin or the like. It is preferable to use the one that has been used.
When the raw material components excluding the first metal ion contain a metal ion corresponding to the first metal ion and the total content thereof exceeds a predetermined amount, the hydroxyamine compound and the basic compound After mixing the organic solvent and other optional components as necessary, by removing foreign substances by filtering and / or reducing the ionic components by an ion exchange resin or the like, a predetermined amount of the first metal ion, the hydroxyamine compound, and A treatment liquid containing a basic compound, an organic solvent, and if necessary, other optional components may be prepared.

When a concentrated solution of the treatment liquid is prepared, the concentrated solution is diluted to obtain a diluted solution before performing the cleaning step B, and then the cleaning step B is performed using this diluted solution. .. At this time, the above dilution is preferably carried out using a diluent containing water.

<Washing step B>
Examples of the object to be cleaned to be cleaned in the cleaning step B include the above-mentioned laminate, and as described above, the laminate 10 in which holes are formed by performing a dry etching step is exemplified (see FIG. 1). The dry etching residue 12 is attached to the hole 6 in the laminate 10.
The laminate obtained by performing the dry ashing step after the dry etching step may be used as the object to be cleaned.

The method of bringing the treatment liquid into contact with the cleaning target is not particularly limited, and for example, a method of immersing the cleaning target in the treatment liquid placed in the tank, a method of spraying the treatment liquid on the cleaning target, and a method of spraying the treatment liquid on the cleaning target. A method of flowing the treatment liquid into the water, or any combination thereof can be mentioned. From the viewpoint of residue removing performance, a method of immersing the object to be cleaned in the treatment liquid is preferable.

The temperature of the treatment liquid is preferably 90 ° C. or lower, more preferably 25 to 80 ° C., further preferably 30 to 75 ° C., and particularly preferably 40 to 70 ° C.

The cleaning time can be adjusted according to the cleaning method used and the temperature of the treatment liquid.
When cleaning by a dipping batch method (a batch method in which a plurality of objects to be cleaned are immersed and processed in a treatment tank), the cleaning time is preferably 60 minutes or less, more preferably 1 to 60 minutes, and 3 to 20 minutes. Minutes are more preferred, and 4 to 15 minutes are particularly preferred.

When washing by the single-wafer method, the washing time is preferably 10 seconds to 5 minutes, more preferably 15 seconds to 4 minutes, further preferably 15 seconds to 3 minutes, and particularly preferably 20 seconds to 2 minutes.

Further, a mechanical stirring method may be used in order to further improve the cleaning ability of the treatment liquid.
Examples of the mechanical stirring method include a method of circulating the treatment liquid on the object to be cleaned, a method of flowing or spraying the treatment liquid on the object to be cleaned, and a method of stirring the treatment liquid by ultrasonic waves or megasonic. And so on.

<Rinse process B2>
The method for cleaning a substrate using the treatment liquid of the present invention may further include a step of rinsing and cleaning the object to be cleaned with a solvent (hereinafter referred to as "rinsing step B2") after the cleaning step B. ..
The rinsing step B2 is preferably performed continuously with the washing step B and is a step of rinsing with a rinsing solvent (rinsing solution) for 5 seconds to 5 minutes. The rinsing step B2 may be performed by using the above-mentioned mechanical stirring method.

Examples of the rinsing solvent include deionized (DI: De Ionize) water, methanol, ethanol, isopropyl alcohol, N-methylpyrrolidinone, γ-butyrolactone, dimethyl sulfoxide, ethyl lactate and propylene glycol monomethyl ether acetate. It is not limited to. Alternatively, an aqueous rinse solution having a pH> 8 (diluted aqueous ammonium hydroxide, etc.) may be used.
As the rinsing solvent, ammonium hydroxide aqueous solution, DI water, methanol, ethanol, or isopropyl alcohol is preferable, ammonium hydroxide aqueous solution, DI water, or isopropyl alcohol is more preferable, and ammonium hydroxide aqueous solution or DI water is further preferable.
As a method of bringing the rinse solvent into contact with the object to be cleaned, the above-mentioned method of bringing the treatment liquid into contact with the object to be cleaned can be similarly applied.
The temperature of the rinsing solvent in the rinsing step B2 is preferably 16 to 27 ° C.

<Drying process B3>
The method for cleaning a substrate using the treatment liquid of the present invention may include a drying step B3 for drying the object to be cleaned after the rinsing step B2.
The drying method is not particularly limited. Examples of the drying method include a spin drying method, a method of flowing a dry gas over an object to be cleaned, a method of heating a substrate by a heating means such as a hot plate or an infrared lamp, a flatulence drying method, a rotagoni drying method, and an IPA. (Isopropyl alcohol) drying method, or any combination thereof can be mentioned.
The drying time depends on the specific method used, but is generally preferably 30 seconds to several minutes.

The objects to be cleaned in the method for cleaning a substrate using the treatment liquid of the present invention are a metal layer, an interlayer insulating layer, and a metal hard including one or more selected from the group consisting of W and Co on the substrate as described above. It is not limited to a laminate having masks at least in this order. That is, for example, it is also used for removing a photoresist etching residue of a laminate having a metal layer containing at least one selected from the group consisting of W and Co, an interlayer insulating layer, and a photoresist film on the substrate in this order. it can.

The present invention will be described in more detail below based on examples. The materials, amounts used, proportions, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as restrictive by the examples shown below. Unless otherwise specified, "%" means "mass%".

[Preparation of treatment solution 1]
The treatment solutions (treatment solutions 1 to 8) shown in Table 1 were prepared respectively. The contents of various components used in each treatment liquid (all based on mass) are as described in the table.

Here, all of the various components shown in Table 1 are classified into semiconductor grades or high-purity grades equivalent thereto, and the liquid components are further filtered and purified multiple times. used.
A mixed solution was prepared by mixing each component so as to have the formulation shown in Table 1. The first metal ion and the second metal ion were introduced into the liquid by adding a metal salt (metal chloride) containing the corresponding metal atom.
The content of metal ions in the treatment liquid was measured by the method described above. Those below the detection limit were measured after appropriately concentrating the drug solution, and the converted value was used.

The abbreviations in Table 1 are as follows.
HA: Hydroxylamine HAS: Hydroxylamine Sulfate DTPA: Diethylenetriamine pentaacetic acid EGBE: Ethylene glycol monobutyl ether 5M-BTA: 5-Methyl-1H-benzotriazole DBU: Diazabicycloundecene

[Evaluation]
Each of the treatment solutions prepared above was evaluated in various ways as shown below.

[Stability of anticorrosion performance against Co film over time]
The temporal stability of the anticorrosion performance against the Co film was evaluated using each of the treatment solutions of Examples and Comparative Examples. Specifically, it is as follows.
<Manufacturing a substrate with a Co film>
A substrate having a Co film formed on one surface of a substrate (silicon wafer (diameter: 12 inches)) by a CVD (Chemical Vapor Deposition) method was prepared.
<Etching test>
The Co film was etched using the prepared treatment solutions of Examples and Comparative Examples. The lower the etching rate for the Co film measured in this test, the better the anticorrosion performance for the Co film. The details of the etching test will be described below.

(1) Etching rate at the time of Fresh (ER _Fr )
The substrate on which the Co film was formed was immersed in a treatment liquid (hereinafter, also referred to as “fresh”) (65 ° C.) immediately after preparation for 5 minutes. Next, the etching rate (Å / min) of the treatment liquid with respect to the Co film was calculated from the difference in the film thickness of the Co film before and after immersion in the treatment liquid, and the etching rate was _{defined as ER Fr.}
The film thickness of the Co film before and after the treatment was measured using ellipsometry (spectral ellipsometer, trade name "Vase", manufactured by JA Woolam Japan Co., Ltd.) in a measurement range of 250 to 1000 nm and a measurement angle of 70 degrees. And measured under the condition of 75 degrees.

(2) Etching rate after thermocycle treatment (ER _Age )
Each of the treatment liquids of Examples and Comparative Examples was sealed in a resin container at 24 ° C. and atmospheric pressure. The resin container was a clean bottle manufactured by Aicello Chemical Corporation, and the total capacity of the container was 500 ml. Then, for each treatment liquid sealed in the container, a total of 7 days of 5 days at the refrigerated storage temperature of -5 ° C → 2 days at room temperature (24 ° C) is set as one set, and this is performed 26 times (182 days). Repeated thermocycle processing was performed. Next, the substrate on which the Co film was formed was immersed in the treatment solution (65 ° C.) after the thermocycle treatment for 5 minutes, and the difference in the film thickness of the Co film before and after immersion in the treatment solution showed that the treatment solution The etching rate (Å / min) for the Co film was calculated, and the etching rate was defined as ER _Age .

(3) Calculation and evaluation of etching rate maintenance rate Based on the obtained etching rates ER _Fr and ER _Age , the etching rate maintenance rate (etching rate maintenance rate (%) = ER _Age / ER _Fr × 100) is calculated. , The stability of anticorrosion performance against Co film over time was evaluated.
The closer the etching rate maintenance rate (%) is to 100%, the better the maintenance rate of the anticorrosion performance against the Co film. That is, the anticorrosion performance against the Co film is stable over time.
The etching rate maintenance rate (%) was evaluated based on the following evaluation criteria.
(Evaluation criteria)
"AAA": Etching rate maintenance rate (%) is 100 to 102%
"AA": Etching rate maintenance rate (%) is more than 102% and 106% or less "A +": Etching rate maintenance rate (%) is more than 106% and 114% or less "A-": Etching rate maintenance rate (%) is 114 % More than 130% "B": Etching rate maintenance rate (%) is more than 130% and less than 200% "C": Etching rate maintenance rate (%) is more than 200% and less than 430% "D": Etching rate maintenance rate ( %) Is over 430%

The etching rate maintenance rate (%) is preferably 100 to 114%, more preferably 100 to 106%, and even more preferably 100 to 102%.

[Stability over time for residue removal]
Using each of the treatment solutions of Examples and Comparative Examples, the stability over time of residue removability was evaluated.
_{In the following evaluation, a model film made of TiO 2,} which is a kind of residue generated when MHM (metal hard mask) is plasma-etched, is prepared, and the etching rate is evaluated to evaluate the residue removability over time. Stability was evaluated. Model membranes composed of TiO ₂ (TiO ₂ film) is provided in a film thickness of 1000Å on a Si substrate.

<Etching test>
_{The TiO 2} film was etched using the prepared treatment solutions of Examples and Comparative Examples. The higher the etching rate for the _{TiO 2} film measured in this test, the better the residue removal performance. The details of the etching test will be described below.

(1) Etching rate at the time of Fresh (ER _Fr )
The _{substrate provided with the nitro 2} film was immersed in the treatment liquid (“fresh) (65 ° C.) immediately after preparation for 5 minutes. Then, from the difference in the film thickness _{of the dio 2 film before and after the immersion in the treatment liquid,} The etching rate (Å / min) of the treatment liquid with _{respect to the TiO 2 film was calculated, and the etching rate was defined as ER Fr.
The film thickness of the TiO 2} film before and after the treatment was measured using ellipsometry (spectral ellipsometer, trade name "Vase", manufactured by JA Woolam Japan Co., Ltd.) in a measuring range of 250 to 1000 nm and a measuring angle of 70. It was measured under the conditions of degree and 75 degrees.

(2) Etching rate after thermocycle treatment (ER _Age )
Each of the treatment liquids of Examples and Comparative Examples was sealed in a resin container at 24 ° C. and atmospheric pressure. The resin container was a clean bottle manufactured by Aicello Chemical Corporation, and the total capacity of the container was 500 ml. Then, for each treatment liquid sealed in the container, a total of 7 days of 5 days at the refrigerated storage temperature of -5 ° C → 2 days at room temperature (24 ° C) is set as one set, and this is performed 26 times (182 days). Repeated thermocycle processing was performed. Next, _{the substrate provided with the TiO 2} film is immersed in the treatment liquid (65 ° C.) after the thermocycle treatment for 5 minutes, and the treatment is performed based on the difference in the thickness _{of the dio 2 film before and after the immersion in the treatment liquid.} The etching rate (Å / min) of the liquid with _{respect to the TiO 2} film was calculated, and the etching rate was defined as ER _Age .

(3) Calculation and evaluation of etching rate maintenance rate Based on the obtained etching rates ER _Fr and ER _Age , the etching rate maintenance rate (etching rate maintenance rate (%) = ER _Age / ER _Fr x 100) is calculated. , The stability of the residue removability over time was evaluated.
The closer the etching rate maintenance rate (%) is to 100%, the better the maintenance rate of the residue removal performance. That is, the residue-removing property with time is good.
The etching rate maintenance rate (%) was evaluated based on the following evaluation criteria.
(Evaluation criteria)
"AAA": Etching rate maintenance rate (%) is 97 to 100%
"AA": Etching rate maintenance rate (%) is 92% or more and less than 97% "A +": Etching rate maintenance rate (%) is 86% or more and less than 92% "A-": Etching rate maintenance rate (%) is 78 % Or more and less than 86% "B": Etching rate maintenance rate (%) is 70% or more and less than 78% "C": Etching rate maintenance rate (%) is 60% or more and less than 70% "D": Etching rate maintenance rate ( %) Is less than 60%

The etching rate retention rate (%) is preferably 86 to 100%, more preferably 92 to 100%, and even more preferably 97 to 100%.

〔result〕
The table below shows the formulation of each treatment solution and the test results.
In Table 1, the description of "remaining portion" shown as the water content is adjusted so that the finally obtained treatment liquid contains the amount of the component shown in the column of each component, and then the remaining component is contained. It means that it is water.
In Table 2 (No. 1) to Table 9 (No. 3), in the "ERFr (Å / min)" column, the "Co ERFr" and " _{TIO 2} ERFr" columns are the respective treatment liquids at the time of fresh. It means the etching rate (Å / min) for the Co film and the TiO _{2 film.}
In Table 2 (No. 1) to Table 9 (No. 3), in the "ERAge (Å / min)" column, the "Co ERAge" and " _{TIO 2} ERAge" columns are the thermocycle treatment of each treatment liquid, respectively. It means the etching rate (Å / min) for the Co film and the TiO _{2 film later.}
In the following, Table 1 shows the basic compositions of the treatment liquids 1 to 8.
Tables 2 (No. 1) to (No. 4) show the composition and content of the first metal ion and the second metal ion in the treatment liquid 1 in Table 1, and the evaluation result of the treatment liquid 1. That is, for example, the treatment liquid of Example 1001 shown in Table 2 (No. 1) is the treatment liquid 1 shown in Table 1, and Na, Al, K, Ca, Cr, Fe, Ni, as the first metal ion. All metal ions selected from the group consisting of and Zn are contained in a total content of 400.0 mass ppb with respect to the total mass of the treatment liquid, and Li, Mg, Mn, Cu, Ag, as second metal ions. It is a treatment liquid containing 5.55 mass ppb in total content with respect to the total mass of the treatment liquid, which contains all the metal ions selected from the group consisting of Pb and Co.
Tables 3 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 2 in Table 1, and the evaluation results of the treatment liquid 2. The treatment liquid 2 does not contain the second metal ion (below the detection limit).
Tables 4 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 3 in Table 1, and the evaluation results of the treatment liquid 3. The treatment liquid 3 does not contain the second metal ion (below the detection limit).
Tables 5 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 4 in Table 1, and the evaluation results of the treatment liquid 4. The treatment liquid 4 does not contain the second metal ion (below the detection limit).
Tables 6 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 5 in Table 1, and the evaluation results of the treatment liquid 5. The treatment liquid 5 does not contain the second metal ion (below the detection limit).
Tables 7 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 6 in Table 1, and the evaluation results of the treatment liquid 6. The treatment liquid 6 does not contain the second metal ion (below the detection limit).
Tables 8 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 7 in Table 1, and the evaluation results of the treatment liquid 7. The treatment liquid 7 does not contain the second metal ion (below the detection limit).
Tables 9 (No. 1) to (No. 3) show the composition and content of the first metal ion in the treatment liquid 8 in Table 1, and the evaluation results of the treatment liquid 8. The treatment liquid 8 does not contain the second metal ion (below the detection limit).

[Preparation of treatment solution 2]
In the above-mentioned treatment liquids of Examples 1001 to 1017, the total content of the second metal ions contained in each treatment liquid was adjusted to be 20.0 mass ppb (each of Examples 1001A to 1017A). ) Was adjusted and the same evaluation was carried out. As a result, the etching rate maintenance rate (%) for the Co film deteriorated, and each treatment liquid was in the numerical range of more than 102% and 106% or less (evaluation: AA). Deterioration was also observed in the etching rate retention rate (%) for the TiO ₂ film, and each treatment liquid was in the numerical range of 92% or more and less than 97% (evaluation: AA).

[Preparation of treatment solution 3]
In the above-mentioned treatment liquids of Examples 1001 to 1017, the total content of the second metal ions contained in each treatment liquid was adjusted to be 0.004 mass ppb (each of Examples 1001B to 1017B). ) Was adjusted and the same evaluation was carried out. As a result, the etching rate retention rate (%) for the Co film deteriorated, and each treatment liquid was in the numerical range of more than 102% and 106% or less (evaluation: AA). Deterioration was also observed in the etching rate retention rate (%) for the TiO ₂ film, and each treatment liquid was in the numerical range of 92% or more and less than 97% (evaluation: AA).

From the results shown in Preparation 1 of the above-mentioned treatment liquid (Table 2 (No. 1) to Table 9 (No. 3)) and the results shown in Preparation 2 and 3 of the above-mentioned treatment liquid, the treatment liquid of the example was stored in a refrigerator and kept at room temperature. It is clear that the performance stability of the residue removal performance and the anticorrosion performance is excellent even if the temperature environment is changed repeatedly.
From the results shown in Preparation 1 of the above-mentioned treatment liquid (Table 2 (No. 1) to Table 9 (No. 3)) and the results shown in Preparation 2 and 3 of the above-mentioned treatment liquid, when the treatment liquid satisfies the requirement X1 shown below. (Preferably, when the treatment liquid satisfies the requirements X1 and Y1 (corresponding to Examples 1001A to 1017A and Examples 1001B to 1017B), more preferably when the treatment liquid satisfies the requirements X1 and the requirement Y2 (Examples 1001 to 1017). It is clear that it is superior in performance stability of residue removal performance and anticorrosion performance.
(Requirement X1) The treatment liquid contains two or more first metal ions, and the content of each metal ion is 1.0 mass ppb to 100.0 mass ppb with respect to the total mass of the treatment liquid. is there.
(Requirement Y1) The treatment liquid contains a second metal ion.
(Requirement Y2) The treatment liquid contains two or more kinds of second metal ions, and the total content thereof is 0.01 mass ppb to 10.0 mass ppb with respect to the total mass of the treatment liquid, and further, the treatment liquid. The content of each second metal ion contained therein is 0.01 mass ppb to 1.0 mass ppb with respect to the total mass of the treatment liquid.

On the other hand, it is clear that the treatment liquid of the comparative example cannot achieve both the residue removal performance and the anticorrosion performance stability when the temperature environment changes such as refrigerated storage and room temperature standing are repeated.

1 Substrate 2 Metal layer 3 Etching stop layer 4 Interlayer insulation layer 5 Metal hard mask 6 holes 10 Laminate 11 Inner wall 11a Cross-section wall 11b Bottom wall 12 Dry etching residue

Claims (7)

1. Hydroxylamine compounds selected from the group consisting of hydroxyamines and hydroxyamine salts, and
   With organic solvent
   Basic compounds and
   A treatment liquid containing one or more first metal ions selected from the group consisting of Na, Al, K, Ca, Cr, Fe, Ni, and Zn.
   A treatment liquid having a total content of the first metal ions of 7.0 mass ppb to 800.0 mass ppb with respect to the total mass of the treatment liquid.
2. Claimed that the content of at least one metal ion among the first metal ions contained in the treatment liquid is 1.0 mass ppb to 100.0 mass ppb with respect to the total mass of the treatment liquid. The treatment liquid according to 1.
3. The first metal ion contained in the treatment liquid is two or more kinds, and the content of each metal ion is 1.0 mass ppb to 100.0 mass ppb with respect to the total mass of the treatment liquid. The treatment liquid according to claim 1 or 2.
4. Further, it contains one or more second metal ions selected from the group consisting of Li, Mg, Mn, Cu, Ag, Pb, and Co.
   The treatment liquid according to any one of claims 1 to 3, wherein the total content of the second metal ion is 0.01 mass ppb to 10.0 mass ppb with respect to the total mass of the treatment liquid.
5. The claim that the content of at least one metal ion among the second metal ions contained in the treatment liquid is 0.01 mass ppb to 1.0 mass ppb with respect to the total mass of the treatment liquid. The treatment liquid according to 4.
6. The second metal ion contained in the treatment liquid is two or more kinds, and the content of each metal ion is 0.01 mass ppb to 1.0 mass ppb with respect to the total mass of the treatment liquid. The treatment liquid according to claim 4 or 5.
7. The treatment solution according to any one of claims 1 to 6, wherein the hydroxyamine compound contains at least one selected from the group consisting of hydroxyamine and hydroxyamine sulfate.

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