Treatment liquid, method for treating substrate using same, and method for manufacturing semiconductor substrate

Abstract

Provided are: a treatment liquid containing at least one anti-corrosive agent selected from the group consisting of compounds (1) represented by general formula (1), hydrates of the compounds (1), and salts of the compound (1), the treatment liquid also containing an etchant and water; a method for treating a substrate using the treatment liquid; and a method for manufacturing a semiconductor substrate. (In the formula, R1 represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alicyclic hydrocarbon group, or a substituted or unsubstituted aromatic hydrocarbon group; R2 represents a hydrogen atom or a carbonyl-group-containing organic group; and R1 and R2 may be bonded to each other to form a ring structure.)

Description

Treatment liquid, substrate treatment method using same, and semiconductor substrate manufacturing method

[0001] The present invention relates to a processing liquid, a substrate processing method using the same, and a semiconductor substrate manufacturing method.

[0002] In the wiring formation process, for example, a hard mask layer (HM layer) is formed on an interlayer insulating film in which a substrate, a metal wiring layer, an etching stop layer, and a silicon-based interlayer insulating film are laminated in this order, and the HM layer is etched to form a prototype of a wiring pattern. The HM layer may be made of titanium nitride (TiN) or titanium oxide (TiO ｘ ) are included.

[0003] Next, the interlayer insulating film is dry-etched using the etched HM layer as a mask to create a wiring pattern similar to that of the mask.The HM layer is then removed, and a copper metal film, for example, is embedded in the interlayer insulating film in the shape of the wiring pattern by electroplating.

[0004] After dry etching, the element (substrate / metal wiring layer / etching stop layer / interlayer insulating film / HM layer) has Ti-containing residues and Si-containing residues derived from the HM layer and the interlayer insulating film attached thereto.

[0005] As a treatment liquid for such substrates, for example, Patent Document 1 describes a stripping composition containing an organic solvent, a nucleophilic amino, and a reducing agent.

[0006] Patent No. 2819392

[0007] The above-mentioned processing solution is required to be able to suppress damage to metal wiring layers and etching stop layers using various metals while also having good cleaning properties. In this regard, there is room for improvement in achieving both suppression of damage to titanium atom-containing metal layers such as TiN, aluminum atom-containing metal layers such as aluminum oxide, or copper substrates and copper atom-containing metal layers, and residue removability when removing titanium-based residues (residues containing titanium or titanium-based alloys) and silicon-based residues (residues containing silicon atoms). For these reasons, there is a need for the development of a processing solution that can suppress damage to metal-containing layers containing titanium atoms, aluminum atoms, copper atoms, etc., and that is excellent in removing residues containing titanium atoms, silicon atoms, etc.

[0008] The present invention has been made in view of the above circumstances, and aims to provide a processing solution that can suppress damage to a metal-containing layer while also achieving cleaning properties, a substrate processing method using the same, and a semiconductor substrate manufacturing method.

[0009] As a result of intensive research to achieve the above-mentioned object, the present inventors have found that a treatment liquid containing at least one corrosion inhibitor selected from the group consisting of compound (1) having a specific structure, a hydrate of this compound (1), and a salt of this compound (1), an etchant, and water can be obtained, and have thus completed the present invention.

[0010] That is, the present invention is as follows: [1] A treatment liquid containing at least one anticorrosive agent selected from the group consisting of a compound (1) represented by the following general formula (1), a hydrate of the compound (1), and a salt of the compound (1), an etchant, and water:

[0011]

[0012] (In the formula, R １ represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alicyclic hydrocarbon group, or a substituted or unsubstituted aromatic hydrocarbon group; R ２ represents a hydrogen atom or an organic group containing a carbonyl group, R １ and R ２ ​may be bonded to each other to form a ring structure. １ and R ２ [3] The treatment liquid according to [1] or [2], wherein the compound (1) is a compound (1-1) represented by the following formula (1-1) or a compound (1-2) represented by the following formula (1-2):

[0013]

[0014] (In the formula, R ３ represents a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 15 carbon atoms, a substituted or unsubstituted alicyclic hydrocarbon group having 1 to 15 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group.

[0015]

[0016] ​​[4] The treatment liquid according to [1] or [2], wherein the etchant is at least one selected from the group consisting of hydrogen peroxide, hydrogen fluoride, hydroxylamine, hydroxylamine derivatives, and alkanolamines. [5] The treatment liquid according to [1] or [2], further comprising a pH adjuster. [6] The treatment liquid according to [1] or [2], wherein the pH is 4 to 13. [7] The treatment liquid according to [1] or [2], wherein the treatment liquid is for treating an etched substrate, the substrate having a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms. [8] A substrate treatment method, comprising the step of treating an etched substrate with the treatment liquid according to [1] or [2]. [9] The substrate treatment method according to [8], wherein the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

[10] A method for producing a semiconductor substrate, comprising a step of treating a substrate after etching with the treatment liquid according to [1] or [2].

[11] The method for producing a semiconductor substrate according to

[10] , wherein the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

[0017] According to the present invention, it is possible to provide a processing solution that can suppress damage to a metal-containing layer while also achieving good cleaning properties, a substrate processing method using the same, and a semiconductor substrate manufacturing method.

[0018] FIG. 1 is a simplified cross-sectional view showing an example of a substrate to be treated with a treatment liquid according to this embodiment.

[0019] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The following present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be practiced by appropriately modifying it within the scope of its gist. Furthermore, unless otherwise specified, the configurations and parameters disclosed in this specification can be arbitrarily combined. Furthermore, unless otherwise specified, the upper and lower limit values ​​of the values ​​disclosed in this specification can be arbitrarily combined.

[0020] In the drawings, the same elements are given the same reference numerals, and redundant explanations will be omitted. Furthermore, unless otherwise specified, the positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to the ratios shown in the drawings.

[0021] <Processing liquid>

[0022] The treatment liquid according to this embodiment is a treatment liquid containing at least one anticorrosive selected from the group consisting of compound (1) represented by the following general formula (1), a hydrate of compound (1), and a salt of compound (1), an etchant, and water. The treatment liquid according to this embodiment is also sometimes called a "cleaning liquid" or a "treatment liquid for semiconductor devices," etc.

[0023]

[0024] (In the formula, R １ represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alicyclic hydrocarbon group, or a substituted or unsubstituted aromatic hydrocarbon group; R ２ represents a hydrogen atom or an organic group containing a carbonyl group, R １ and R ２ may be bonded to each other to form a ring structure.

[0025] By using the cleaning solution according to this embodiment, it is possible to achieve both high levels of damage suppression on at least titanium atom-containing metal layers such as TiN, aluminum atom-containing metal layers such as aluminum oxide, or copper substrates or copper atom-containing metal layers, and high levels of residue removability when removing titanium-based residues (residues containing titanium or titanium-based alloys), silicon-based residues (residues containing silicon atoms), etc. The reason for this is unclear, but is presumed to be as follows: Compound (1) functions as an adsorbent, and the adsorption effect of Compound (1) is thought to enable both damage suppression on metal layers and residue removability to be achieved (however, the functions and effects of this embodiment are not limited to this).

[0026] ​The titanium-based residue refers to a residue containing titanium or a titanium-based alloy. The titanium-based alloy refers to a state in which other metal elements or nonmetal elements are bonded to titanium, which is a metal. As will be described in detail later, the titanium-based alloy includes, for example, titanium oxide (TiO ｘ (where x represents a number)), titanium fluoride (TiF ｘ Examples of the silicon-based residue include silicon (Si), silicon oxide (SiO), titanium oxynitride (TiON), titanium oxyfluoride (TiOF), etc. ｘ (where x represents a number), silicon fluoride (SiF ｘ (where x represents a number), silicon bromide (SiBr ｘ (where x represents a number)), silicon chloride (SiCl ｘ (where x represents a number) are examples.

[0027] The treatment liquid according to this embodiment can be suitably used as a cleaning liquid for removing etching residues containing not only the titanium-based residues and silicon-based residues described above, but also organic and inorganic substances. In this case, the treatment liquid can be suitably used as a cleaning liquid for semiconductor (device) cleaning, etc. The etching residues are by-products generated by etching such as dry etching, and include, for example, organic residues derived from photoresists and other metal-containing residues other than titanium-based residues and silicon-based residues.

[0028] The inorganic substances mentioned above are compounds containing metals, such as metals, metal oxides, metal nitrides, metal chlorides, metal fluorides, etc. That is, the treatment liquid according to this embodiment can efficiently remove etching residues containing such inorganic substances.

[0029] More specifically, the treatment solution according to this embodiment can efficiently remove titanium-based residues and silicon-based residues derived from protective films such as hard mask layers (HM layers) and other layers. In addition, the treatment solution according to this embodiment is expected to efficiently remove inorganic-containing residues derived from metal wiring layers, including metals described below, and one selected from the group consisting of metal oxides, metal nitrides, metal chlorides, and metal fluorides of these metals.

[0030] Examples of the metal include tantalum (Ta), copper (Cu), cobalt (Co), ruthenium (Ru), aluminum (Al), tungsten (W), molybdenum (Mo), gold (Au), silver (Ag), iron (Fe), nickel (Ni), lead (Pb), zinc (Zn), tin (Sn), magnesium (Mg), bismuth (Bi), cadmium (Cd), titanium (Ti), zirconium (Zr), antimony (Sb), manganese (Mn), beryllium (Be), chromium (Cr), germanium (Ge), vanadium (V), gallium (Ga), hafnium (Hf), indium (In), niobium (Nb), rhenium (Re), and thallium (Tl), as well as at least one selected from the group consisting of metal oxides, metal nitrides, metal chlorides, and metal fluorides thereof.

[0031] Examples of the metal oxide include metal oxides of the above-mentioned metal atoms. Specific examples of the metal oxide include TaO. ｘ , CuO ｘ , CoO ｘ , RuO ｘ , AlO ｘ , W.O. ｘ , MoO ｘ , AuO ｘ , AgO ｘ , FeO ｘ , NiO ｘ (Unless otherwise specified, x represents a number.) Examples include, but are not limited to,

[0032] Examples of the metal nitride include metal nitrides of the above-mentioned metal atoms. Specific examples of the metal nitride include TaN. ｘ , CuN ｘ , CoN ｘ , RuNｘ , AlN ｘ , W.N. ｘ , MoN ｘ , AuN ｘ , AgN ｘ , FeN ｘ , NiN ｘ These include, but are not limited to:

[0033] Examples of metal chlorides include metal chlorides of the above-mentioned metal atoms. Specific examples of metal chlorides include TaCl. ｘ , CuCl ｘ , CoCl ｘ , RuCl ｘ , AlCl ｘ , WCl ｘ , MoCl ｘ , AuCl ｘ , AgCl ｘ , FeCl ｘ , NiCl ｘ These include, but are not limited to:

[0034] Examples of the metal fluoride include metal fluorides of the above-mentioned metal atoms. Specific examples of the metal fluoride include TaF ｘ , CuF ｘ , CoF ｘ , RuF ｘ , AlF ｘ , W.F. ｘ , MoF ｘ , AuF ｘ , AgF ｘ , FeF ｘ , NiF ｘ These include, but are not limited to:

[0035] As will be described in detail later, the treatment solution according to this embodiment is suitable for removing etching residues, and is particularly suitable for removing dry etching residues. Generally, dry etching residues are removed before the next process in order to improve semiconductor yields and prevent deterioration of electrical characteristics. For example, the treatment solution according to this embodiment is suitable for cleaning semiconductor substrates after dry etching in a wiring process.

[0036] For example, the treatment solution according to this embodiment can suitably remove titanium-based residues containing titanium or titanium-based alloys derived from the HM layer that adhere during the wiring process, residues containing silicon-based compounds derived from the HM layer, and etching residues containing inorganic substances derived from the metal wiring layer. In particular, titanium-based residues that adhere to semiconductor substrates after dry etching have high wet resistance and are difficult to remove by cleaning treatment. The treatment solution according to this embodiment can also efficiently clean such residues.

[0037] Components that can be blended into the treatment liquid according to this embodiment will be described below by way of example.

[0038] (Anticorrosion Agent)

[0039] The treatment liquid according to this embodiment contains at least one anticorrosive selected from the group consisting of compound (1) represented by the following general formula (1), a hydrate of compound (1), and a salt of compound (1):

[0040]

[0041] (In the formula, R １ represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alicyclic hydrocarbon group, or a substituted or unsubstituted aromatic hydrocarbon group; R ２ represents a hydrogen atom or an organic group containing a carbonyl group, R １ and R ２ may be bonded to each other to form a ring structure.

[0042] R in general formula (1) １ and R ２ At least one of the above is preferably a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 15 carbon atoms.

[0043] The compound (1) is preferably a compound (1-1) represented by the following formula (1-1) or a compound (1-2) represented by the following formula (1-2). By using such a compound, both metal corrosion resistance and cleaning properties can be achieved at a higher level.

[0044] ​​

[0045] (In the formula, R ３ represents a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 15 carbon atoms, a substituted or unsubstituted alicyclic hydrocarbon group having 1 to 15 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group.

[0046] R ３ When is an aliphatic hydrocarbon group, it preferably has 1 to 13 carbon atoms. The upper limit of the carbon number is more preferably 10 or less, and even more preferably 8 or less. The lower limit of the carbon number is preferably 1 or more, more preferably 3 or more, and even more preferably 5 or more. In this case, an example of a preferred numerical range for the carbon number is more preferably 1 to 10, even more preferably 1 to 8, even more preferably 3 to 8, and still more preferably 5 to 8. Examples of the aliphatic hydrocarbon group include chain saturated hydrocarbon groups and chain unsaturated hydrocarbon groups, and of these, chain saturated hydrocarbon groups are preferred.

[0047] R ３ When is an alicyclic hydrocarbon group, it preferably has 1 to 13 carbon atoms. The upper limit of the number of carbon atoms is more preferably 10 or less, and even more preferably 8 or less. The lower limit of the number of carbon atoms is preferably 1 or more, more preferably 3 or more, and even more preferably 5 or more. In this case, an example of a preferable numerical range for the number of carbon atoms is more preferably 1 to 10, even more preferably 1 to 8, even more preferably 3 to 8, and still more preferably 5 to 8. Examples of alicyclic hydrocarbon groups include cycloalkane groups and cycloalkene groups, and among these, cycloalkane groups are preferred.

[0048] R ３ When R is an aromatic hydrocarbon group, specific examples thereof include a phenyl group and a naphthyl group, and among these, a phenyl group is preferred. ３When is an aromatic hydrocarbon group, the substituent is preferably a hydroxyl group (OH) or an alkyl group (e.g., a methyl group), and more preferably a hydroxyl group. Suitable examples of the aromatic hydrocarbon group having a substituent include a hydroxyl group-containing aromatic hydrocarbon group (e.g., a phenol group) and an alkyl group-containing aromatic hydrocarbon group (e.g., a methyl group).

[0049]

[0050] Specific preferred examples of the compound represented by formula (1-1) include alkylhydroxamic acids such as acetohydroxamic acid, butyrylhydroxamic acid, hexanehydroxamic acid, octanohydroxamic acid, and decanohydroxamic acid, benzohydroxamic acid, salicylhydroxamic acid, etc. Also preferred is N-hydroxy-5-norbornene-2,3-dicarboximide represented by formula (1-2).

[0051] The type of hydrate of the above-mentioned compound is not particularly limited, and known hydrates can be used.

[0052] The type of salt of the above-mentioned compound is not particularly limited. Furthermore, hydrates of such salts can also be used. Specific examples of salts include, but are not particularly limited to, sodium salts, potassium salts, ammonium salts, and alkylammonium salts (e.g., tetramethylammonium salts). Hydrates of these salts may also be used.

[0053] The treatment solution according to this embodiment may further contain another anticorrosive agent (second anticorrosive agent) in addition to the above-described anticorrosive agent (first anticorrosive agent). Examples of the other anticorrosive agents include imidazole ring-containing compounds, triazole ring-containing compounds, pyridine ring-containing compounds, pyrimidine ring-containing compounds, tetrazole ring-containing compounds, pyrazole ring-containing compounds, purine ring-containing compounds, phenanthroline ring-containing compounds, thiol-containing compounds, phosphonic acid-containing compounds, and phosphinic acid-containing compounds.

[0054] The anticorrosive agent may be used alone or in combination of two or more kinds.

[0055] ​The content of the anticorrosive agent in the treatment solution according to this embodiment is not particularly limited, but is preferably 0.00005 to 1.0 mass %. The upper limit of the content is more preferably 0.1 mass % or less, and even more preferably 0.05 mass % or less. The lower limit of the content is preferably 0.0005 mass % or more. By keeping the content of the anticorrosive agent within this range, it is possible to achieve both metal corrosion prevention and cleaning performance at a higher level.

[0056] (etchant)

[0057] The etchant is not particularly limited, and a suitable type can be selected in consideration of the type of metal layer to be treated. A suitable example of the etchant is preferably at least one selected from the group consisting of hydrogen peroxide, hydrogen fluoride, hydroxylamine, hydroxylamine derivatives, and alkanolamines. By using such an etchant, both metal corrosion and cleaning properties can be achieved at a higher level.

[0058] Specific examples of the hydroxylamine derivative include N-methylhydroxylamine, N-ethylhydroxylamine, N,N-diethylhydroxylamine, hydroxyurea, N,N-dibenzylhydroxylamine, 1,1'-(hydroxyimino)bis[2-propanol], and N-isopropylhydroxylamine.

[0059] Specific examples of alkanolamines include monoethanolamine, diethanolamine, triethanolamine, aminoethylethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, diethanolisopropanolamine, N-methylethanolamine, and N-methyldiethanolamine.

[0060] The etchants may be used alone or in combination of two or more.

[0061] The content of the etchant in the treatment liquid according to this embodiment is not particularly limited, but is preferably 0.1 to 30% by mass. The upper limit of the content is more preferably 20% by mass or less, even more preferably 10% by mass or less, even more preferably 8% by mass or less, and even more preferably 6% by mass or less. The lower limit of the content is more preferably 0.2% by mass or more, even more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more. By keeping the content of the etchant within this range, it is possible to achieve both metal corrosion and cleaning properties at a higher level.

[0062] (water)

[0063] The treatment liquid according to this embodiment contains water, and from the viewpoint of suitability for manufacturing semiconductor devices, for example, deionized water (DIW) can be used as the water.

[0064] The water content in the treatment solution according to this embodiment is not particularly limited, but is preferably 60 to 99.99 mass %. When the water content is high, it can be suitably used as a so-called aqueous treatment solution, but the water content can also be selected according to the application, taking into consideration the type of metal to be cleaned, etc. During preparation, necessary components other than water may be added, with water being added as the remainder.

[0065] The treatment liquid according to this embodiment may contain other components in addition to the components described above, such as a pH adjuster, a buffer, a chelating agent, a surfactant, etc.

[0066] (pH adjuster)

[0067] The treatment liquid according to this embodiment may contain a pH adjuster to achieve a predetermined pH. Specific examples of the pH adjuster are not particularly limited, and a suitable pH adjuster can be selected in consideration of the intended use and the components contained therein. Examples of pH adjusters include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), and ammonia (NH ３), ethylenediamine, diethylenetriamine, methanesulfonic acid (MSA), acetic acid, sulfuric acid, phosphoric acid, hydrochloric acid, etc. ３ ) can be, for example, ammonia water (e.g., NH ３ H ２ O and NH ４ It may also be added as hydroxypropyl.

[0068] The pH adjuster may be used alone or in combination of two or more. Alternatively, the treatment liquid according to this embodiment may not contain a pH adjuster.

[0069] (Buffering agent)

[0070] The treatment liquid according to this embodiment may contain a buffering agent. A buffering agent is a compound that has the effect of suppressing changes in the pH of the treatment liquid. By including a buffering agent, the pH of the treatment liquid can be efficiently controlled to a predetermined value. The buffering agent is not particularly limited as long as it is a compound that has pH buffering ability. Specific examples of buffering agents include Good's buffers.

[0071] The buffering agent may be used alone or in combination of two or more. Alternatively, the treatment liquid according to this embodiment may not contain a buffering agent.

[0072] (chelating agent)

[0073] The treatment solution according to this embodiment may contain a chelating agent. A chelating agent is a compound capable of forming a complex with metal ions. The inclusion of a chelating agent can improve cleaning properties and improve the stability of the chemical solution by inactivating the metal ions. The chelating agent is not particularly limited as long as it is a compound with multiple coordination sites. Suitable examples of chelating agents include ethylenediaminetetraacetic acid (EDTA), citric acid, nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA), hydroxyethylethylenediaminetriacetic acid (HEDTA), triethylenetetraminehexaacetic acid (TTHA), 1,3-propanediaminetetraacetic acid (PDTA), 1,3-diamino-2-hydroxypropanetetraacetic acid (DPTA-OH), hydroxyethyliminodiacetic acid (HIDA), and dihydroxyethylglycine. (DHEG), glycol ether diamine tetraacetic acid (GEDTA), dicarboxymethyl glutamic acid (CMGA), ethylenediamine disuccinic acid (EDDS), 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC), ethylenediamine tetramethylene phosphonic acid (EDTMP), and at least one selected from the group consisting of nitrilotrismethylene phosphonic acid (NTMP).

[0074] The chelating agent may be used alone or in combination of two or more. Alternatively, the treatment liquid according to this embodiment may not contain a chelating agent.

[0075] (Surfactant)

[0076] The treatment liquid according to this embodiment may contain a surfactant for the purpose of adjusting the wettability of the treatment liquid with respect to the substrate, etc. Examples of the surfactant include a nonionic surfactant, an anionic surfactant, a cationic surfactant, and an amphoteric surfactant.

[0077] Examples of nonionic surfactants include polyalkylene oxide alkyl phenyl ether surfactants, polyalkylene oxide alkyl ether surfactants, block polymer surfactants consisting of polyethylene oxide and polypropylene oxide, polyoxyalkylene distyrene-substituted phenyl ether surfactants, polyalkylene tribenzyl phenyl ether surfactants, and acetylene polyalkylene oxide surfactants.

[0078] Examples of anionic surfactants include alkyl sulfonic acids, alkyl benzene sulfonic acids, alkyl naphthalene sulfonic acids, alkyl diphenyl ether sulfonic acids, fatty acid amide sulfonic acids, polyoxyethylene alkyl ether carboxylic acids, polyoxyethylene alkyl ether acetic acids, polyoxyethylene alkyl ether propionic acids, alkyl phosphonic acids, and salts of fatty acids. These salts are not particularly limited, but include, for example, sodium salts, potassium salts, ammonium salts, and alkyl ammonium salts (e.g., tetramethylammonium salts).

[0079] Examples of cationic surfactants include alkylpyridium surfactants and quaternary ammonium salt surfactants.

[0080] Examples of amphoteric surfactants include betaine surfactants, amino acid surfactants, imidazoline surfactants, and amine oxide surfactants.

[0081] These surfactants are generally commercially available. The surfactants may be used alone or in combination of two or more.

[0082] When the treatment liquid according to this embodiment contains a surfactant, the content of the surfactant is not particularly limited, but is, for example, preferably 0.0001 to 5% by mass relative to the total mass of the treatment liquid. The lower limit of the content is more preferably 0.0002% by mass or more, and even more preferably 0.002% by mass or more. The upper limit of the content is more preferably 3% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.2% by mass or less.

[0083] The treatment liquid according to this embodiment may not contain one or more surfactants selected from the group consisting of nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants, and may not contain one or more of the compounds exemplified above as these surfactants. The treatment liquid according to this embodiment may not contain a surfactant.

[0084] (organic solvent)

[0085] The treatment liquid according to this embodiment may further contain an organic solvent, provided that the effect of the treatment liquid is not impaired. The organic solvent is preferably a water-soluble organic solvent. Examples of water-soluble organic solvents include alcohols (e.g., isopropanol, ethanol, ethylene glycol, propylene glycol, glycerin, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, diethylene glycol, dipropylene glycol, furfuryl alcohol, 2-methyl-2,4-pentanediol, 3-methoxy-3-methyl-1-butanol, etc.), dimethyl sulfoxide, ethers (e.g., ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, propylene glycol dimethyl ether), and morpholines (e.g., N-methylmorpholine N-oxide).

[0086] The organic solvents may be used alone or in combination of two or more.

[0087] When the treatment liquid according to this embodiment contains an organic solvent, the content of the organic solvent is preferably 0.05 to 50% by mass or less, based on the total content of water and organic solvent. The upper limit is more preferably 30% by mass or less, even more preferably 20% by mass or less, and even more preferably 10% by mass or less. The lower limit may be 0.1% by mass or more.

[0088] The treatment liquid according to the present embodiment is preferably an aqueous treatment liquid from the viewpoints of component solubility, environmental load reduction, cost efficiency, etc. An aqueous treatment liquid is a treatment liquid that does not contain an organic solvent, or a treatment liquid that contains water and an organic solvent and in which the organic solvent content is lower than the water content. From these viewpoints, a more preferred embodiment is one in which the organic solvent content in the treatment liquid according to the present embodiment is preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, even more preferably 3% by mass or less, and even more preferably 0% by mass or less (i.e., the solvent is water only).

[0089] (Impurities, etc.)

[0090] The treatment liquid according to this embodiment may contain metal impurities containing at least one metal atom selected from the group consisting of, for example, Fe atoms, Cr atoms, Ni atoms, Zn atoms, Ca atoms, and Pb atoms.

[0091] The total content of metal atoms in the treatment liquid according to this embodiment is preferably 100 mass ppt or less, relative to the total mass of the treatment liquid. The lower limit of the total content of metal atoms is preferably as low as possible, and may be, for example, 0.001 mass ppt or more. The total content of metal atoms may be, for example, 0.001 mass ppt to 100 mass ppt. By setting the total content of metal atoms to the above-mentioned preferred upper limit or less, it is believed that the defect suppression and residue suppression properties of the treatment liquid are improved. By setting the total content of metal atoms to the above-mentioned preferred lower limit or more, it is believed that metal atoms are less likely to be isolated and present in the system, and that adverse effects on the overall production yield of the object to be cleaned are less likely to be exerted.

[0092] The content of metal impurities can be adjusted, for example, by a purification treatment such as filtering, etc. The purification treatment such as filtering may be performed on a part or all of the raw materials before preparing the treatment liquid, or may be performed after preparing the treatment liquid.

[0093] The treatment liquid according to this embodiment may contain, for example, impurities derived from organic substances (organic impurities). The total content of the above-mentioned organic impurities in the treatment liquid according to this embodiment is preferably 5000 ppm by mass or less. The lower limit of the organic impurity content is preferably as low as possible, and may be, for example, 0.1 ppm by mass or more. The total content of organic impurities may be, for example, 0.1 ppm by mass to 5000 ppm by mass.

[0094] The treatment liquid according to this embodiment may contain countable entities of a size that can be counted by, for example, a light-scattering liquid-borne particle counter. The size of the countable entities is, for example, 0.04 μm or more. The number of countable entities in the treatment liquid according to this embodiment is, for example, 1,000 or less per mL of treatment liquid, with the lower limit being, for example, 0.1 or more. By keeping the number of countable entities in the treatment liquid within the above-mentioned range, it is believed that the metal corrosion suppression effect and defect suppression effect of the treatment liquid are improved (however, the effects of this embodiment are not limited to these).

[0095] The organic impurities and / or the counted entities may be added to the treatment liquid, or may be inevitably mixed into the treatment liquid during the manufacturing process of the treatment liquid. Examples of inevitable mixing in the treatment liquid during the manufacturing process include, but are not limited to, cases where organic impurities are contained in raw materials (e.g., organic solvents) used to manufacture the treatment liquid, and cases where organic impurities are mixed in from the external environment during the manufacturing process of the treatment liquid (e.g., contamination).

[0096] When the objects to be counted are added to the processing solution, the abundance ratio may be adjusted for each specific size, taking into consideration the surface roughness of the object to be cleaned, etc.

[0097] The treatment solution according to this embodiment can be used for various purposes. Among these, from the viewpoint of effectively utilizing the effects and advantages of this embodiment, it is particularly suitable as a treatment solution for semiconductor substrates including a substrate and a film formed on the substrate, the film containing at least one selected from the group consisting of silicon atoms, titanium atoms, aluminum atoms, and copper atoms. Furthermore, it is also suitable for cleaning semiconductor substrates on which a film containing titanium atoms has been formed, specifically, for cleaning semiconductor substrates on which a film containing at least one selected from the group consisting of titanium and titanium-based alloys has been formed. More specifically, a preferred example of this embodiment is a treatment solution for semiconductor substrates, including a substrate and a film formed on the substrate, the film containing at least one selected from the group consisting of titanium and titanium-based alloys. A more preferred example is a semiconductor substrate (semiconductor substrate) including a substrate, a film containing at least one selected from the group consisting of titanium and titanium-based alloys, and a film containing at least one selected from the group consisting of silicon atoms, aluminum atoms, and copper atoms. Such a semiconductor substrate can exhibit the effects and advantages of this embodiment, namely, excellent removability of titanium-based residues and excellent protection of the metal layer to be protected.

[0098] The pH of the treatment liquid according to this embodiment is not particularly limited, but is preferably 4 to 13. The lower limit of the pH is more preferably 5 or more, even more preferably 6 or more, even more preferably 7 or more, and still more preferably 8 or more. The upper limit of the pH is more preferably 12 or less, even more preferably 11 or less. By keeping the pH within this range, it is possible to achieve an even higher level of balance between damage suppression of the metal-containing layer and residue removability.

[0099] The treatment liquid according to this embodiment can be suitably used as a treatment liquid for treating a substrate after etching. Specifically, the treatment liquid is a treatment liquid for treating a substrate after etching, and is more suitable when the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

[0100] Here, a substrate that can be used as a treatment target with the treatment liquid according to this embodiment will be described with reference to FIG.

[0101] FIG. 1 is a simplified cross-sectional view showing an example of a substrate to be treated with a treatment liquid according to this embodiment.

[0102] 1 includes a substrate 10, a metal wiring layer 20, an etching stop layer 30, and an interlayer insulating film 40 laminated in this order, and a hard mask layer (HM layer) 50 formed on the interlayer insulating film 40 (substrate 10 / metal wiring layer 20 / etching stop layer 30 / interlayer insulating film 40 / HM layer 50). That is, the unprocessed substrate 100 includes the metal wiring layer 20 and the etching stop layer 30 as metal-containing layers.

[0103] This unprocessed substrate 100 is one that has been dry-etched in a wiring process, i.e., one that has been dry-etched on the interlayer insulating film 40 using the HM layer 50, on which the prototype of the wiring pattern has been formed by dry etching, as a mask. Dry etching residues 60 adhere to the side surfaces of the HM layer 50 and the interlayer insulating film 40. Note that, although the case of etching by dry etching is described here as an example, if etching is performed by wet etching, for example, the resulting residues will be wet-etching residues.

[0104] In the spaces between the interlayer insulating films 40 in the wiring pattern, the metal wiring layer 20 and the etching stop layer 30 are exposed, and dry etching residues 60 are also attached.

[0105] The substrate 10 may be made of a material such as silicon, amorphous silicon, or glass.

[0106] The metal wiring layer 20 is a wiring layer containing metals such as molybdenum (Mo), tungsten (W), ruthenium (Ru), copper (Cu), gold (Au), silver (Ag), iron (Fe), nickel (Ni), silicon (Si), aluminum (Al), lead (Pb), zinc (Zn), tin (Sn), tantalum (Ta), magnesium (Mg), cobalt (Co), bismuth (Bi), cadmium (Cd), titanium (Ti), zirconium (Zr), antimony (Sb), manganese (Mn), beryllium (Be), chromium (Cr), germanium (Ge), vanadium (V), gallium (Ga), hafnium (Hf), indium (In), niobium (Nb), rhenium (Re), and thallium (Tl), as well as one of their metal oxides, metal nitrides, metal chlorides, and metal fluorides.

[0107] The metal wiring layer 20 is not limited to wiring, but also broadly includes functional layers such as electrodes, insulating layers, low-dielectric layers, and various conductor layers. It includes layers formed by using the above-mentioned various metals, as well as their metal oxides, metal nitrides, metal chlorides, and metal fluorides. For example, in the case of silicon-based materials, SiN, SiO ２ , Low-k films (SiOC films, SiCOH films, etc.), ILD, etc. are examples.

[0108] The material of the etching stop layer 30 is not particularly limited. For example, the etching stop layer 30 may be made of aluminum oxide (AlO ｘ ), SiN, SiON, and SiOCN-based materials are exemplified.

[0109] The material of the interlayer insulating film 40 is not particularly limited as long as it has insulating properties, and a suitable material can be selected in consideration of manufacturing conditions, etc. The interlayer insulating film 40 may be made of, for example, SiO ２ Layers containing silicon-based materials such as SiN, SiOC, SiOCN, etc. may be used.

[0110] The material of the HM layer 50 is not particularly limited as long as it functions as a protective film against etching, and a suitable material can be selected as appropriate taking into consideration the manufacturing conditions, etc. For example, a layer containing titanium and a titanium-based alloy can be suitably used as the HM layer 50. The treatment liquid according to this embodiment is excellent at removing at least titanium-based residues, and can therefore efficiently remove residues (see dry etching residues 60) generated from the HM layer 50 using such materials. Examples of titanium-based alloys include titanium nitride (TiN), titanium oxide (TiO ｘ (where x represents a number), titanium-based materials such as titanium oxynitride (TiON), titanium oxyfluoride (TiOF), etc. can be used.

[0111] The dry etching residue 60 is primarily a Ti-containing residue containing titanium-based materials derived from the HM layer 50, but is not limited to such a residue. The dry etching residue 60 also includes, for example, the above-mentioned etching residue containing inorganic substances. The treatment liquid according to this embodiment is suitable for removing the above-mentioned titanium-based residue.

[0112] <Processing method>

[0113] The treatment liquid according to this embodiment can be suitably used as a method for treating a semiconductor substrate. A suitable example of the method for treating a substrate according to this embodiment is a method for treating a substrate including a step of treating a substrate after etching using the treatment liquid described above. From the viewpoint of fully achieving the effects of this embodiment described above, the substrate preferably has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms. In this case, the treatment target is a substrate laminate including a substrate and a metal layer formed on the substrate, and the metal layer may, for example, contain at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

[0114] Here, an exemplary processing method according to this embodiment will be described with reference to Fig. 1. The cleaning method according to this embodiment is a process of cleaning an unprocessed substrate 100 after dry etching in a wiring process using the above-described processing liquid. The cleaning method is not particularly limited, and any known cleaning method can be used.

[0115] Examples of cleaning operations include a method in which the treatment liquid is continuously applied onto the untreated substrate 100 rotating at a constant speed (spin coating method), a method in which the untreated substrate 100 is immersed in the treatment liquid for a certain period of time (dip method), and a method in which the treatment liquid is sprayed onto the surface of the untreated substrate 100 (spray method).

[0116] The temperature at which the cleaning treatment is carried out is not particularly limited, but is preferably carried out under conditions of 10 to 80°C. The lower limit of the cleaning treatment temperature (temperature of the treatment liquid) is more preferably 15°C or higher, and even more preferably 20°C or higher. The upper limit of the cleaning treatment temperature (temperature of the treatment liquid) is more preferably 75°C or lower, even more preferably 70°C or lower, and even more preferably 50°C or lower. By setting the lower limit of the cleaning treatment temperature within the above-mentioned range, the removability of etching residues can be further improved. Furthermore, by setting the upper limit of the cleaning treatment temperature within the above-mentioned range, unintended composition changes in the treatment liquid can be more effectively suppressed, and cleaning can be carried out more efficiently in terms of workability, safety, cost, etc.

[0117] The cleaning time can be appropriately selected to be a time sufficient to remove etching residues, impurities, and the like adhering to the surface of the unprocessed substrate 100. The cleaning time is preferably, for example, 10 seconds to 30 minutes. The lower limit of the cleaning time is more preferably 20 seconds or more, and even more preferably 30 seconds or more. The upper limit of the cleaning time is more preferably 15 minutes or less, and even more preferably 10 minutes or less. Depending on the mode of use, it is expected that the desired effect can be obtained even with a time of 5 minutes or less.

[0118] Since cleaning is performed using the treatment solution according to this embodiment, in the pre-processed substrate 100 on which the dry etching residues 60 have been attached, the dry etching residues 60 originating from the HM layer 50, which is a protective film, can be effectively cleaned and removed while suppressing damage to the metal wiring layer 20, the etching stop layer 30, the interlayer insulating film 40, and the HM layer 50. In particular, in the case of an HM layer containing titanium and / or a titanium alloy, the treatment solution according to this embodiment is particularly suitable because of its excellent ability to remove titanium-based residues.

[0119] In addition, by using the treatment liquid according to this embodiment, damage to not only protective films such as the HM layer 50 but also various functional layers (metal wiring layer 20, etching stop layer 30, interlayer insulating film 40, etc.) can be suppressed.

[0120] <Semiconductor manufacturing method>

[0121] The treatment liquid according to this embodiment and the treatment method using the same can be suitably used as a method for manufacturing a semiconductor substrate. A suitable example of the method for manufacturing a semiconductor substrate according to this embodiment is a method for manufacturing a semiconductor substrate, which includes a step of treating a substrate after etching with the treatment liquid described above. From the viewpoint of being able to fully exert the effects of this embodiment described above, it is preferable that the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

[0122] A specific example of the semiconductor manufacturing method according to this embodiment is a semiconductor manufacturing method including the steps of: (1) preparing a substrate having a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms; (2) etching the substrate; and (3) removing impurities from the substrate after etching by contacting the substrate with the treatment liquid. Hereinafter, the cleaning of an unprocessed substrate 100 shown in FIG. 1 will be described as an example.

[0123] (1) preparing a substrate having a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms;

[0124] In step (1), a substrate having a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms is prepared. Although not shown, in the case of Fig. 1, a pre-etching laminate (substrate 10 / metal wiring layer 20 / etching stop layer 30 / interlayer insulating film 40 / HM layer 50) is prepared, which includes, in this order, a substrate 10, a metal wiring layer 20, an etching stop layer 30, an interlayer insulating film 40, and a hard mask layer (HM layer) 50 corresponding to a protective film.

[0125] The method for sequentially stacking the metal wiring layer 20, the etching stop layer 30, the interlayer insulating film 40, and the hard mask layer (HM layer) 50 corresponding to the protective film on the substrate 10 is not particularly limited, and any known method can be adopted.

[0126] (2) Etching the substrate

[0127] Next, the substrate is etched. By etching, the unprocessed substrate 100 shown in FIG. 1 can be obtained. The etching method is not particularly limited, and may be wet etching or dry etching, but dry etching is preferable. Dry etching is advantageous in that it allows metal wiring at the nano-level and the gas used can be controlled. Furthermore, dry etching is concerned in that it can cause relatively large damage to the substrate, etc., but by using the treatment solution according to this embodiment, such damage can be effectively suppressed, which is desirable in that it can more effectively reflect the advantages of this embodiment.

[0128] In the case of dry etching, plasma can be used. Usually, when plasma etching is performed, there are problems that the substrate is easily damaged and that plasma etching residue is generated, which must be cleaned with a processing solution. However, the use of the processing solution according to the present embodiment is preferable in that such problems can be effectively suppressed.

[0129] (3) After etching, the process of removing impurities from the substrate by contacting the substrate with the above-described treatment solution. The treatment method according to the present embodiment described above can be used for the process (3). This allows a semiconductor substrate from which residues have been removed to be obtained. Furthermore, if necessary, known post-treatments can be performed after cleaning.

[0130] As described above, the treatment liquid according to this embodiment can be used, for example, as a treatment liquid for removing residues generated in a semiconductor etching process or the like, and is particularly suitable for removing residues generated by dry etching. The treatment liquid according to this embodiment has the advantages of suppressing damage to titanium atom-containing metal layers such as TiN, aluminum atom-containing metal layers such as aluminum oxide, and copper substrates and copper atom-containing metal layers, and of being excellent in residue removal properties when removing titanium-based residues (residues containing titanium or titanium-based alloys) and silicon-based residues (residues containing silicon atoms). Therefore, as a treatment liquid for use after etching titanium or titanium-based alloys, or substrates having a silicon atom-containing hard mask layer (HM layer), the treatment liquid according to this embodiment can be more effective than conventional treatment liquids.

[0131] The present invention will be explained in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples in any way.

[0132] 1. Experiment 1

[0133] (Comparative Example 1-1)

[0134] First, as a reference (Ref.), a treatment liquid of Comparative Example 1-1 was prepared with the proportions shown in Table 1. The treatment liquid of Comparative Example 1-1 was an aqueous treatment liquid containing 1.0 mass % hydrogen peroxide as an etchant, no anticorrosive agent, 0.02 mass % tetramethylammonium hydroxide (TMAH) as a pH adjuster, and deionized water (DIW) as the remainder. The pH of the treatment liquid was 9.5.

[0135] (Comparative Examples 1-2 to 1-4, Examples 1-1 to 1-12)

[0136] A treatment liquid having the composition shown in Table 1 was prepared in the same manner as in Comparative Example 1-1.

[0137] (Method for measuring pH)

[0138] The pH of the treatment solution was measured at a temperature of 22° C. using a pH / ORP meter (portable pH meter "ORION STAR A324", manufactured by Thermo Scientific). The pH measurement method was the same in other experiments (Examples and Comparative Examples) unless otherwise specified.

[0139] (Metal Corrosion Evaluation Method)

[0140] First, a copper film (500 nm thick), a titanium nitride film (50 nm thick), or an aluminum oxide film (5 nm thick) was formed on a substrate (12-inch silicon substrate) by PVD. These substrates were then cut into 2 cm x 2 cm pieces (as viewed from above) to prepare test samples (wafer coupons).

[0141] Next, the copper sample and the titanium nitride sample were dissolved in a diluted hydrogen fluoride solution (HF / H ２ DHF cleaning was performed by immersing the wafers in DHF (0.25 O) at room temperature for 1 minute. After the DHF cleaning, the wafers were rinsed with water at room temperature for 30 seconds and dried with nitrogen blow to prepare untreated samples. On the other hand, the aluminum oxide samples were prepared without the above-mentioned DHF cleaning. These untreated samples were then placed in a 100 mL beaker containing 80 mL of the prepared treatment solution and immersed in the treatment solution at 25°C. After the predetermined immersion time, the wafer coupons were removed from the cleaning solution, rinsed with water at room temperature for 30 seconds, and dried with nitrogen blow. The immersion time for the copper sample was 10 minutes, the immersion time for the titanium nitride sample was 30 minutes, and the immersion time for the aluminum oxide sample was 10 minutes.

[0142] The film thickness of the sample (wafer coupon) was measured before and after immersion in the cleaning solution. The film thicknesses of the copper, titanium nitride, and aluminum oxide films were measured by X-ray fluorescence spectroscopy (XRF) using an X-ray electron spectrometer (Rigaku Corporation, Primus IV). The etching rate ("ER": Å / min) was calculated from the change in film thickness before and after the cleaning process. Metal corrosion was evaluated by determining the ratio of each example and comparative example to the reference value, using the etching rate of the corresponding comparative example (Ref.) 1-1 as the reference value, and judging the results according to the following criteria. The best evaluation of the copper sample, titanium nitride sample, and aluminum oxide sample is listed in the table. For example, the treatment solution marked "A" in the table indicates that at least one of the copper sample, titanium nitride sample, and aluminum oxide sample evaluation results was "A." A: The etching rate was 20% or more lower than that of the corresponding comparative example 1-1. B: The etching rate was decreased by less than 20% or increased by less than 20% from the etching rate of the corresponding Comparative Example 1-1. C: The etching rate was increased by 20% or more from the etching rate of the corresponding Comparative Example 1-1.

[0143] (Method for evaluating cleaning properties)

[0144] First, a substrate (12-inch silicon substrate) was prepared by PVD, on which a titanium-based metal-containing film (titanium oxide: film thickness 250 nm) or an amorphous silicon film (film thickness 100 nm) was formed. These substrates were cut into 2 cm x 2 cm pieces in top view to prepare test samples.

[0145] Next, the sample was dissolved in a diluted hydrogen fluoride solution (HF / H ２ The wafer coupon was immersed in DHF cleaning solution (DHF 0) for 1 minute at room temperature. The wafer coupon was then rinsed with water at room temperature for 30 seconds and dried with nitrogen to obtain an untreated sample. The untreated sample was then placed in a 100 mL beaker containing 80 mL of the prepared treatment solution and immersed in the treatment solution at 25°C. After 30 minutes of immersion, the wafer coupon was removed from the cleaning solution, rinsed with water at room temperature for 30 seconds, and dried with nitrogen.

[0146] The film thickness of the wafer coupon was measured before and after immersion in the cleaning solution. The titanium oxide film thickness was measured by X-ray fluorescence analysis (XRF) using an X-ray electron spectrometer (Rigaku Corporation, "Primus IV"). The amorphous silicon film thickness was measured using an ellipsometer (M-2000, J.A. Woolam). The etching rate was calculated from the change in the film thickness of the titanium oxide film or amorphous silicon film before and after the cleaning process.

[0147] The evaluation of cleaning performance was performed by using the etching rate of Comparative Example 1-1, which is the corresponding comparative example (Ref.), as a reference value, and determining the ratio of each Example and Comparative Example to that reference value, and judging the performance according to the following criteria. The best evaluations of the titanium-based metal-containing film and amorphous silicon film evaluation results are listed in the table. For example, treatment solutions marked "A" in the table are those for which one or more of the evaluation results of the titanium-based metal-containing film and amorphous silicon film were "A." A: The etching rate was increased by 10% or more from the corresponding Comparative Example 1-1. B: The etching rate was increased by less than 10% or decreased by less than 10% from the corresponding Comparative Example 1-1. C: The etching rate was decreased by 10% or more from the corresponding Comparative Example 1-1.

[0148] Table 1 shows the composition and evaluation results for each example and comparative example of Experiment 1. In the table, "[ ]" indicates the content (mass %). Furthermore, "-" next to a component indicates that the component was not added.

[0149]

[0150] 2. Experiment 2

[0151] (Comparative Example 2-1)

[0152] First, as a reference (Ref.), a treatment solution of Comparative Example 2-1 was prepared in the proportions shown in Table 2. The treatment solution of Comparative Example 2-1 was an aqueous treatment solution containing 1.0 mass % hydrogen peroxide as an etchant, no anticorrosive agent, 0.05 mass % tetramethylammonium hydroxide (TMAH) as a pH adjuster, 0.05 mass % ethylenediaminetetraacetic acid (EDTA) as an additive, and deionized water (DIW) as the balance. The pH of the treatment solution was 9.5.

[0153] (Examples 2-1 to 2-5)

[0154] A treatment liquid having the composition shown in Table 2 was prepared in the same manner as in Comparative Example 2-1.

[0155] (Metal Corrosion Evaluation Method)

[0156] Metal corrosion was evaluated in accordance with the evaluation method of Experiment 1, except that Comparative Example 2-1 was used as the reference. That is, for the evaluation of metal corrosion in Experiment 2, the etching rate value of Comparative Example 2-1 was used as the reference value, and the ratio of each Example and Comparative Example to that reference value was calculated and judged according to the following criteria: A: The etching rate was reduced by 20% or more from the corresponding etching rate of Comparative Example 2-1. B: The etching rate was reduced by less than 20% or increased by less than 20% from the corresponding etching rate of Comparative Example 2-1. C: The etching rate was increased by 20% or more from the corresponding etching rate of Comparative Example 2-1.

[0157] (Method for evaluating cleaning properties)

[0158] Except for the fact that Comparative Example 2-1 was used as the reference, the cleaning performance was evaluated in accordance with the evaluation method of Experiment 1. That is, the cleaning performance in Experiment 2 was evaluated by using the etching rate value of Comparative Example 2-1 as the reference value, determining the ratio of each Example and Comparative Example to that reference value, and judging based on the following criteria: A: The etching rate was increased by 10% or more from the corresponding etching rate of Comparative Example 2-1. B: The etching rate was increased by less than 10% or decreased by less than 10% from the corresponding etching rate of Comparative Example 2-1. C: The etching rate was decreased by 10% or more from the corresponding etching rate of Comparative Example 2-1.

[0159] 3. Experiments 3-18

[0160] In Experiments 3 to 18, the corresponding comparative example (Ref.) was used as a reference value, and the ratio of each example (and each comparative example) to the reference value was calculated in the same manner as in Experiments 1 and 2, and metal corrosion and cleanability were evaluated according to the following criteria.

[0161] In the case of Experiment 3 (Comparative Example 3-1, Example 3-1), Comparative Example 3-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 4 (Comparative Example 4-1, Example 4-1), Comparative Example 4-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 5 (Comparative Example 5-1, Example 5-1), Comparative Example 5-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 6 (Comparative Example 6-1, Example 6-1), Comparative Example 6-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 7 (Comparative Example 7-1, Example 7-1), Comparative Example 7-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 8 (Comparative Example 8-1, Example 8-1), Comparative Example 8-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 9 (Comparative Example 9-1, Example 9-1), Comparative Example 9-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 10 (Comparative Example 10-1, Example 10-1), Comparative Example 10-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 11 (Comparative Example 11-1, Example 11-1), Comparative Example 11-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 12 (Comparative Example 12-1, Example 12-1), Comparative Example 12-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 13 (Comparative Example 13-1, Example 13-1), Comparative Example 13-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 14 (Comparative Example 14-1, Example 14-1), Comparative Example 14-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 15 (Comparative Example 15-1, Example 15-1), Comparative Example 15-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 16 (Comparative Example 16-1, Example 16-1), Comparative Example 16-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 17 (Comparative Example 17-1, Example 17-1), Comparative Example 17-1 was used as the corresponding comparative example (Ref.). In the case of Experiment 18 (Comparative Example 18-1, Example 18-1), Comparative Example 18-1 was used as the corresponding comparative example (Ref.). The treatment solutions for each comparative example and example were prepared to have the compositions shown in Tables 2 to 4.

[0162] (Method for evaluating metal corrosion) A: The etching rate was reduced by 20% or more from the corresponding comparative example. B: The etching rate was reduced by less than 20% or increased by less than 20% from the corresponding comparative example. C: The etching rate was increased by 20% or more from the corresponding comparative example.

[0163] (Method for evaluating cleaning performance) A: The etching rate was increased by 10% or more from the corresponding comparative example. B: The etching rate was increased by less than 10% or decreased by less than 10% from the corresponding comparative example. C: The etching rate was decreased by 10% or more from the corresponding comparative example.

[0164] Tables 2 to 4 show the compositions and evaluation results for each example and comparative example of Experiments 2 to 18. In the tables, "[ ]" indicates the content (mass %). Furthermore, "-" next to a component indicates that the component was not added.

[0165]

[0166]

[0167]

[0168] HF: Hydrogen fluoride TMAH: Tetramethylammonium hydroxide NH ４ OH: Ammonium hydroxide EDTA: Ethylenediaminetetraacetic acid NTMP: Nitrilotrismethylenephosphonic acid HEDTA: Hydroxyethylethylenediaminetriacetic acid

[0169] From the above, it was confirmed that the treatment liquid according to this example has at least an excellent effect of inhibiting metal corrosion and an excellent cleaning effect.

[0170] This application is based on a patent application (Patent Application No. 2024-052719) filed with the Japan Patent Office on March 28, 2024, the contents of which are incorporated herein by reference.

[0171] 10: Substrate 20: Metal wiring layer 30: Etching stop layer 40: Interlayer insulating film 50: Hard mask layer 60: Dry etching residue 100: Unprocessed substrate (substrate stack)

Claims

1. A treatment solution comprising: at least one anticorrosive selected from the group consisting of a compound (1) represented by the following general formula (1), a hydrate of said compound (1), and a salt of said compound (1); an etchant; and water. (In the formula, R １ represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alicyclic hydrocarbon group, or a substituted or unsubstituted aromatic hydrocarbon group; R ２ represents a hydrogen atom or an organic group containing a carbonyl group, R １ and R ２ may be bonded to each other to form a ring structure.

2. R in the general formula (1) １ and R ２ 2. The treatment liquid according to claim 1, wherein at least one of the groups is a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 15 carbon atoms.

3. The treatment liquid according to claim 1 or 2, wherein the compound (1) is a compound (1-1) represented by the following formula (1-1) or a compound (1-2) represented by the following formula (1-2): (In the formula, R ３ represents a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 15 carbon atoms, a substituted or unsubstituted alicyclic hydrocarbon group having 1 to 15 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group.

4. The treatment liquid according to claim 1 or 2, wherein the etchant is at least one selected from the group consisting of hydrogen peroxide, hydrogen fluoride, hydroxylamine, hydroxylamine derivatives, and alkanolamines.

5. The treatment liquid according to claim 1 or 2, further comprising a pH adjuster.

6. The treatment liquid according to claim 1 or 2, which has a pH of 4 to 13.

7. The treatment liquid according to claim 1 or 2, which is a treatment liquid for treating a substrate after etching, wherein the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

8. A method for treating a substrate, comprising the step of treating an etched substrate with the treatment liquid according to claim 1 or 2.

9. The method for treating a substrate according to claim 8, wherein the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

10. A method for manufacturing a semiconductor substrate, comprising the step of treating an etched substrate with the treatment liquid according to claim 1 or 2.

11. The method for producing a semiconductor substrate according to claim 10, wherein the substrate has a layer containing at least one metal selected from the group consisting of titanium atoms, aluminum atoms, and copper atoms.

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