Processing solution, method for processing semiconductor substrate, and method for manufacturing semiconductor

Abstract

To provide a processing solution capable of efficiently removing zirconium-based residues while exhibiting excellent corrosion resistance, a cleaning method for semiconductor substrates using the solution, and a method for manufacturing a semiconductor.SOLUTION: A processing solution containing (A) compounds capable of releasing fluoride ions, (B) at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of Group III elements in the periodic table, and (C) water, a method for processing semiconductor substrates using the same, and a method for manufacturing semiconductors are provided.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a processing liquid, a semiconductor substrate processing method, and a semiconductor manufacturing method. [Background technology]

[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, and an interlayer insulating film such as a silicon-based insulating film are laminated in this order, and then this hard mask layer is etched to form a prototype of the wiring pattern. The material of the mask layer is, for example, zirconium or zirconium oxide (ZrO x Zirconium-based alloys such as (x represents a number) are used.

[0003] Next, the interlayer insulating film is dry-etched using the etched HM layer as a mask layer to form wiring patterns such as metal wiring.

[0004] Dry etching residues have conventionally been removed by a cleaning process. A processing solution containing peroxide as a residue remover has been used to remove dry etching residues (see, for example, Patent Document 1). Furthermore, processing solutions containing hydrogen fluoride have also been used to enhance residue removal. [Prior art documents] [Patent documents]

[0005] Patent Document 1: International Publication No. 2016 / 076033 Summary of the Invention [Problem to be solved by the invention]

[0006] The present inventors have conducted detailed studies on treatment solutions such as hydrogen fluoride and the like and have found that there is room for improvement in achieving both the removal of zirconium-based residues (residues containing zirconium or zirconium-based alloys) and corrosion resistance. For example, when a treatment solution such as hydrogen fluoride is used to remove zirconium-based residues, problems can arise such as damage to various metal layers that are to be protected.

[0007] Furthermore, as a result of various investigations into treatment solutions other than those mentioned above, it was found that there was still room for improvement in achieving both the removal of zirconium-based residues and corrosion prevention properties.

[0008] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a treatment solution that can efficiently remove zirconium-based residues and has excellent anticorrosion properties, as well as a method for cleaning semiconductor substrates and a method for manufacturing semiconductors using the same. [Means for solving the problem]

[0009] As a result of intensive research to achieve the above-mentioned object, the present inventors have discovered that a treatment liquid containing (A) a compound capable of releasing fluoride ions, (B) at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of elements of Group III of the periodic table, and (C) water, has been developed, and have completed the present invention.

[0010] <1> The treatment liquid contains (A) a compound capable of releasing fluoride ions, (B) at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of elements of Group III of the periodic table, and (C) water. <2> The concentration of the ions in the component (B) is 0.0005 to 0.5% by mass. <1> 1. The processing solution according to claim 1. <3> Further, (D) a corrosion inhibitor is contained. <1> 1. The processing solution according to claim 1. <4> Further, (E) an organic solvent is contained. <1> 1. The processing solution according to claim 1. <5> The (D) anticorrosion agent contains a nitrogen-containing heterocycle-containing compound or a salt thereof. <3> 1. The processing solution according to claim 1. <6> The (E) organic solvent contains at least one selected from the group consisting of alcohol-based solvents, glycol ester-based solvents, sulfoxide-based solvents, sulfone-based solvents, amide-based solvents, lactone-based solvents, imidazolidinone-based solvents, nitrile-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, pyrrolidone-based solvents, and urea-based solvents, <4> 1. The processing solution according to claim 1. <7> The content of the (C) water is 0.1 to 99.999 mass%. <1> 1. The processing solution according to claim 1. <8> pH is 2 to 6; <1> 1. The processing solution according to claim 1. <9> the treatment liquid is a treatment liquid for a semiconductor substrate, the semiconductor substrate including a substrate and a film formed on the substrate, the film containing at least one atom selected from the group consisting of silicon atoms, cobalt atoms, zirconium atoms, and aluminum atoms; <1> 1. The processing solution according to claim 1. <10> 1. A method for treating a semiconductor substrate having a protective film, comprising: <1> 1. A method for treating a semiconductor substrate, comprising the step of removing impurities from the semiconductor substrate by contacting the semiconductor substrate with the treatment liquid according to claim 1. <11> A method for manufacturing a semiconductor substrate, the method comprising: preparing a semiconductor substrate having a substrate and a protective film provided on the substrate; etching the semiconductor substrate using the protective film; and, after the etching, <1> and removing impurities from the semiconductor substrate by bringing the treatment liquid according to claim 1 into contact with the semiconductor substrate. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a treatment liquid that can efficiently remove zirconium-based residues and has excellent anticorrosion properties, as well as a method for cleaning semiconductor substrates and a method for manufacturing semiconductors that use the same. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view showing an example of an element (semiconductor substrate) to be cleaned after dry etching. [Figure 2] FIG. 2 is a conceptual diagram illustrating an example of the treatment liquid according to this embodiment. [Figure 3] FIG. 3 is a conceptual diagram illustrating an example of the treatment liquid according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] 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 limits of the values ​​disclosed in this specification can be arbitrarily combined.

[0014] 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.

[0015] <Processing liquid>

[0016] The treatment liquid according to this embodiment contains (A) a compound capable of releasing fluoride ions, (B) at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of elements of Group III of the periodic table, and (C) water. By using such a treatment liquid, zirconium-based residues can be efficiently removed and excellent corrosion prevention properties can be achieved. The zirconium-based residue refers to residues containing zirconium or a zirconium-based alloy. The zirconium-based alloy refers to a form in which other metal elements or non-metal elements are bonded to zirconium, which will be described in detail later. Examples of zirconium-based alloys include zirconium oxide (ZrO x (where x represents a number.)

[0017] The treatment liquid according to this embodiment can be suitably used as a treatment liquid for removing etching residues containing inorganic substances. In this case, it can be suitably used as a treatment liquid for cleaning semiconductors, etc. The treatment liquid may also be called a cleaning liquid, etc.

[0018] The inorganic substance referred to here is a compound containing a metal, such as a metal, a metal oxide, a metal nitride, a metal chloride, a metal fluoride, etc. That is, according to this embodiment, etching residues containing such inorganic substances can be efficiently removed.

[0019] More specifically, the treatment solution according to this embodiment can efficiently remove zirconium-based residues (residues containing zirconium or zirconium alloys) contained in the HM layer and other layers. In addition, the treatment solution according to this embodiment is expected to efficiently remove inorganic residues derived from the metal wiring layer, including metals described below, and one selected from the group consisting of metal oxides, metal nitrides, metal chlorides, and metal fluorides of these metals.

[0020] Examples of metals include molybdenum (Mo), tungsten (W), ruthenium (Ru), copper (Cu), gold (Au), silver (Ag), iron (Fe), nickel (Ni), 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 metal oxides, metal nitrides, metal chlorides, and metal fluorides thereof.

[0021] Examples of metal oxides include metal oxides of the above-mentioned metal atoms. Specific examples of metal oxides include TiO. x , TaO x , CuO x , CoO x , RuO x , AlO x , WO 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,

[0022] Examples of metal nitrides include metal nitrides of the above-mentioned metal atoms. Specific examples of metal nitrides include TiN. x , TaN x , CuN x , CoN x , RuN x , AlN x , W.N. x , MoN x , AuN x , AgN x , FeN x , NiN x These include, but are not limited to:

[0023] Examples of metal chlorides include metal chlorides of the above-mentioned metal atoms. Specific examples of metal chlorides include TiCl x , 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:

[0024] Examples of metal fluorides include metal fluorides of the above-mentioned metal atoms. Specific examples of metal fluorides include TiF x , 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:

[0025] 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.

[0026] For example, the treatment solution according to this embodiment can effectively remove zirconium-based residues (residues containing zirconium or zirconium-based alloys) derived from the HM layer that adheres during the wiring process, and etching residues containing inorganic substances derived from the metal wiring layer. In particular, zirconium-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 efficiently clean such residues. The reason why such effects are obtained is not clear, but is presumed to be as follows (it goes without saying that the functions and effects of this embodiment are not limited to the following).

[0027] 2 and 3 are conceptual diagrams illustrating an example of a treatment liquid according to this embodiment, in which M typically represents a metal ion such as zirconium ion.

[0028] First, in dry etching using metal oxides or metal nitrides such as zirconium as hard masks, MO due to the hard mask material was observed after dry etching. x In this regard, in the treatment liquid according to the present embodiment, (B) at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of elements of Group III of the periodic table is selected from the group consisting of MO x By adsorbing onto the surface of the metal residue (see Figure 2, where x indicates a number), the internal bonds within the residue can be relaxed (see Figure 2).

[0029] Next, the internal bonds within the residue are weakened, making it easier for the fluoride ions of (A) compounds capable of releasing fluoride ions to attack (see "F" in Figure 2). - As a result, the dissolution reaction of the residue can be effectively promoted, and the residue can be effectively removed (see "M a F b - "See ". Note that a and b indicate numbers.)

[0030] It is presumed that after the residue is removed, the ions of component (B) are again adsorbed to another location on the surface of the residue, again contributing to the promotion of adsorption and the dissolution reaction of the residue.

[0031] In this way, component (B) adsorbs to the residue surface and exerts a catalytic action there, effectively accelerating the residue dissolution reaction, which is presumably why the residue can be effectively removed without using a high concentration of component (A).

[0032] In response to this issue, conventional techniques have attempted to improve the removability of zirconium-based metal residues by increasing the concentration of hydrogen fluoride. However, high concentrations of hydrogen fluoride result in greater damage to the metal layer. As a result, it becomes difficult to achieve both high removability of zirconium-based metal residues and corrosion protection for the metal layer. Similar problems can also occur with silicon-based materials that are susceptible to damage by hydrogen fluoride, such as SiN, SiO2, low-k films (e.g., SiOC films and SiCOH films), and ILDs.

[0033] However, the treatment solution according to the present embodiment, by using the components (A) and (B) in combination, is excellent in removing zirconium-based metal residues without increasing the concentration of the component (A). Therefore, damage to the metal layer and the silicon-based material can be suppressed, and therefore, both the ability to remove zirconium-based metal residues and the ability to prevent corrosion of the metal layer and the silicon-based material can be achieved.

[0034] The concentrations (contents) of the components (A) and (B) can be appropriately selected taking into consideration the type of metal layer described above. For example, when using a metal layer or silicon-based material that is susceptible to damage by fluoride ions, the concentration of the component (B) can be determined so that sufficient residue removal can be achieved even with a low fluoride ion concentration. On the other hand, when using a metal layer or silicon-based material that is less susceptible to damage by fluoride ions, a relatively high fluoride ion concentration is acceptable, and the concentration of the component (B) can be determined taking this into consideration.

[0035] The above is an explanation of one example of the treatment liquid according to the present embodiment, and it goes without saying that this does not mean that the composition and usage of the treatment liquid according to the present embodiment are limited to the above.

[0036] The components of the treatment liquid according to this embodiment will be described below.

[0037] ((A) Compound capable of releasing fluoride ions)

[0038] Examples of compounds capable of releasing fluoride ions include hydrogen fluoride (HF), hexafluorosilicic acid, ammonium fluoride, and tetramethylammonium fluoride (TMAF). Among these, hydrogen fluoride is preferable. In the case of hydrogen fluoride, hydrofluoric acid (aqueous solution of hydrogen fluoride) may be added when producing the treatment liquid according to this embodiment.

[0039] The component (A) may be used alone or in combination of two or more types.

[0040] The content of component (A) in the treatment solution according to this embodiment is not particularly limited, but is preferably 0.001 to 10% by mass. The upper limit of the content of component (A) is more preferably 5% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.5% by mass or less. The lower limit of the content of component (A) is more preferably 0.002% by mass or more, even more preferably 0.003% by mass or more, still more preferably 0.004% by mass or more, and even more preferably 0.005% by mass or more. When the content of component (A) is equal to or greater than the above-mentioned lower limit, the removability of zirconium-based residues in the cleaning treatment can be further improved. On the other hand, when the content of component (A) is equal to or less than the above-mentioned upper limit, damage to metal wiring and the like can be further suppressed.

[0041] ((B) At least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of elements of Group III of the periodic table)

[0042] Examples of alkali metal ions include lithium ions (Li + ), sodium ions (Na + ), potassium ions (K + ), rubidium ion (Rb + ), cesium ions (Cs + ), francium ion (Fr + Among these, lithium ions, sodium ions, and potassium ions are preferred.

[0043] Examples of alkaline earth metal ions include calcium ions (Ca 2+ ), barium ions (Ba 2+ ), strontium ions (Sr 2+ ), beryllium ions (Be 2+ ), magnesium ions (Mg 2+ ), radium ions (Ra 2+ ) etc.

[0044] Examples of the ions of group III elements in the periodic table include scandium ions (Sc 3+ ), yttrium ions (Y 3+ Among these, scandium ions (Sc 3+ ) is preferred.

[0045] Of the above, alkali metal ions are preferred as component (B), with lithium ions, sodium ions, and potassium ions being more preferred.

[0046] The component (B) may be used alone or in combination of two or more types.

[0047] The content of component (B) in the treatment solution according to this embodiment is not particularly limited, but is preferably 0.0005 to 0.5% by mass. The upper limit of the content of component (B) is more preferably 0.3% by mass or less, even more preferably 0.2% by mass or less, and even more preferably 0.1% by mass or less. The lower limit of the content of component (B) is more preferably 0.001% by mass or more, even more preferably 0.002% by mass or more, still more preferably 0.003% by mass or more, and even more preferably 0.005% by mass or more. When the content of component (B) is within the above range, it is possible to achieve both high levels of removability of zirconium-based residues and suppression of damage to the metal layer in the cleaning treatment. For example, the treatment solution according to this embodiment can maintain a high level of removability of zirconium-based residues without increasing the concentration of component (A), thereby more effectively suppressing damage to the metal layer caused by component (A).

[0048] Furthermore, in the case of various layers made of silicon-based materials, such as interlayer insulating films, etching stoppers, hard masks, and the like, these layers tend to be susceptible to damage by component (A) such as hydrogen fluoride. However, according to the present embodiment, zirconium-based residues can be sufficiently effectively removed without necessarily increasing the concentration of component (A) such as hydrogen fluoride, thereby suppressing damage to metal layers that are susceptible to damage by component (A) (however, the functions and effects of the present embodiment are not limited to these).

[0049] ((C)Water)

[0050] (C) Water that can be used may be, for example, deionized water (DIW) because it is suitable for manufacturing semiconductor devices.

[0051] The water content of the treatment liquid according to the present embodiment is not particularly limited, but is preferably 0.1 to 99.999 mass %. When the water content is high, the treatment liquid can be suitably used as a so-called aqueous treatment liquid, but the water content can also be selected according to the application, taking into consideration the type of metal to be cleaned, etc.

[0052] For example, when it is desired to reduce damage to a metal (layer) such as aluminum, it is preferable to reduce the water content. On the other hand, when an etching effect on a metal (layer) such as aluminum is required, it is preferable to increase the water content. The water content can be adjusted, for example, by adjusting the content of the organic solvent described below. For example, when it is desired to reduce the water content, the content of the organic solvent can be increased. In this way, it may be possible to selectively use an aqueous treatment liquid (a treatment liquid having a higher water content than the organic solvent content, or a treatment liquid containing no organic solvent) and an organic solvent-based treatment liquid depending on the purpose. From this perspective, one suitable example of the treatment liquid according to this embodiment is, for example, an aqueous treatment liquid (a treatment liquid having a higher water content than the organic solvent content, or a treatment liquid containing no organic solvent).

[0053] Generally, when an aqueous treatment liquid (a treatment liquid in which the water content is higher than the organic solvent content, or a treatment liquid containing no organic solvent) is used, from the viewpoint of achieving both higher levels of residue removability and corrosion prevention, the lower limit of the content of (C) water is more preferably 70 mass% or more, even more preferably 80 mass% or more, and still more preferably 90 mass% or more. Also, the upper limit of the content of (C) water is more preferably 99.99 mass% or less, even more preferably 99.9 mass% or less, and still more preferably 99.0 mass% or less.

[0054] ((D) Corrosion inhibitor)

[0055] The treatment solution according to this embodiment preferably contains an anticorrosive agent when it is desired to further improve the anticorrosive properties of the metal layer. The treatment solution according to this embodiment is expected to have the advantage that, even when an anticorrosive agent is used in combination, the anticorrosive effect of the anticorrosive agent is not reduced and a high anticorrosion effect can be maintained. Note that the anticorrosive agent can be appropriately selected depending on the type of metal layer to be protected, etc.

[0056] Specific examples of the anticorrosive agent include, but are not limited to, at least one selected from the group consisting of a nitrogen-containing heterocycle-containing compound, a lactam ring-containing compound, a mercapto group-containing compound, an aliphatic amine compound, and salts thereof. Among these, the treatment liquid according to the present embodiment preferably contains a nitrogen-containing heterocycle-containing compound or a salt thereof.

[0057] Specific examples of nitrogen-containing heterocycle-containing compounds include imidazole ring-containing compounds, triazole ring-containing compounds, pyridine ring-containing compounds, pyrimidine ring-containing compounds, phenanthroline ring-containing compounds, tetrazole ring-containing compounds, pyrazole ring-containing compounds, and purine ring-containing compounds. Among these, tetrazole ring-containing compounds are preferred. By using a tetrazole ring-containing compound, the corrosion resistance of a layer containing, for example, a metal component such as cobalt or copper as a main component (e.g., a metal wiring layer, an etching stop layer, an interlayer insulating film, or other functional layer) can be further improved. In other words, when the treatment solution according to this embodiment is used, damage (film loss) to a layer containing cobalt, copper, or the like can be more effectively reduced.

[0058] Specific examples of the imidazole ring-containing compound include 1-decyl-3-methylimidazolium chloride, 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-propylimidazole, 2-butylimidazole, 4-methylimidazole, 2,4-dimethylimidazole, 2-undecylimidazole, 2-aminoimidazole, and 2,2'-biimidazole.

[0059] Specific examples of the triazole ring-containing compound include 1,2,4-triazole, 1,2,3-benzotriazole, 1,2,3-triazole, 3-amino-1H-1,2,4-triazole, 5-methyl-1H-benzotriazole (5MBTA), 1-hydroxybenzotriazole, 1-hydroxypropylbenzotriazole, 2,3-dicarboxypropylbenzotriazole, 4-hydroxybenzotriazole, 4-carboxyl-1H-benzotriazole, 4-carboxyl-1H-benzotriazole methyl ester, 4-carboxyl-1H-benzotriazole butyl ester, 4-carboxyl-1H-benzotriazole octyl ester, 5-hexylbenzotriazole, [1,2,3-benzotriazolyl-1-methyl][1,2,4-triazolyl-1-methyl][2-ethylhexyl]amine, tolyltriazole, naphthotriazole, bis[(1-benzotriazolyl)methyl]phosphonic acid, and 3-aminotriazole.

[0060] Specific examples of the pyridine ring-containing compound include 1H-1,2,3-triazolo[4,5-b]pyridine, 1,2,4-triazolo[4,3-a]pyridin-3(2H)-one, 3H-1,2,3-triazolo[4,5-b]pyridin-3-ol, 1-acetyl-1H-1,2,3-triazolo[4,5-b]pyridine, 3-aminopyridine, 4-aminopyridine, 3-hydroxypyridine, 4-hydroxypyridine, 2-acetamidopyridine, 4-pyrrolidinopyridine, 2-cyanopyridine, 2,2'-bipyridyl, 4,4'-dimethyl-2,2'-bipyridyl, 4,4'-di-tert-butyl-2,2'-bipyridyl, and 4,4'-dinonyl-2,2'-bipyridyl.

[0061] Specific examples of the pyrimidine ring-containing compound include pyrimidine, 1,2,4-triazolo[1,5-a]pyrimidine, 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine, 1,3-diphenyl-pyrimidine-2,4,6-trione, 1,4,5,6-tetrahydropyrimidine, 2,4,5,6-tetraaminopyrimidine sulfate, 2,4,5-trihydroxypyrimidine, 2,4,6-triaminopyrimidine, 2,4,6-trichloropyrimidine, 2,4,6-trimethoxypyrimidine, and 2,4,6-triaminopyrimidine. Examples thereof include phenylpyrimidine, 2,4-diamino-6-hydroxylpyrimidine, 2,4-diaminopyrimidine, 2-acetamidopyrimidine, 2-aminopyrimidine, 2-methyl-5,7-diphenyl-(1,2,4)triazolo(1,5-a)pyrimidine, 2-methylsulfanyl-5,7-diphenyl-(1,2,4)triazolo(1,5-a)pyrimidine, 2-methylsulfanyl-5,7-diphenyl-4,7-dihydro-(1,2,4)triazolo(1,5-a)pyrimidine, and 4-aminopyrazolo[3,4-d]pyrimidine.

[0062] Specific examples of the phenanthroline ring-containing compound include 1,10-phenanthroline.

[0063] Specific examples of the tetrazole ring-containing compound include 1H-tetrazole, 5-amino-1H-tetrazole (5am.Tet.), 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 1-(2-diaminoethyl)-5-mercaptotetrazole, and the like.

[0064] Specific examples of the pyrazole ring-containing compound include 3,5-dimethylpyrazole, 3-amino-5-methylpyrazole, 4-methylpyrazole, and 3-amino-5-hydroxypyrazole.

[0065] Specific examples of purine ring-containing compounds include purine.

[0066] Specific examples of lactam ring-containing compounds include polyvinylpyrrolidone (PVP).

[0067] Specific examples of mercapto group-containing compounds include 1-thioglycerol, 3-(2-aminophenylthio)-2-hydroxypropyl mercaptan, 3-(2-hydroxyethylthio)-2-hydroxypropyl mercaptan, 2-mercaptopropionic acid, and 3-mercaptopropionic acid.

[0068] Specific examples of the aliphatic amine compound include alkylamines, dialkylamines, and trialkylamines.

[0069] The anticorrosive agent may also be a salt of the above-mentioned compound. Specific examples of the salt include, but are not limited to, sodium salt, potassium salt, ammonium salt, and alkylammonium salt (e.g., tetramethylammonium salt). The anticorrosive agent may also be a hydrate of the above-mentioned compound.

[0070] Another preferred example from another viewpoint is at least one selected from the group consisting of (a) a five-membered ring-containing compound, (b) a six-membered ring-containing compound, (c) a fused ring-containing compound, (d) an alkylammonium salt, and (e) a heterocycle-containing alkylammonium salt.

[0071] (a) The five-membered ring compound is preferably a nitrogen-containing five-membered ring compound. Specific examples of the five-membered ring compound are preferably compounds having the following structures (compounds (a1) to (a9)) (wherein n represents a number):

[0072] [ka]

[0073] The (b) six-membered ring-containing compound is preferably a nitrogen-containing six-membered ring-containing compound. Specific examples of the six-membered ring-containing compound include compounds having the following structures (compounds (b1) to (b6)).

[0074] [ka]

[0075] The (c) fused ring-containing compound is preferably a nitrogen-containing fused ring-containing compound. Specific examples of the fused ring-containing compound are preferably compounds having the following structures (compounds (c1) to (c5)).

[0076] [ka]

[0077] (d) As the alkylammonium salt, compounds having the following structures (compounds (d1) to (d6)) are preferred: The alkylammonium salts shown below are alkylammonium salts that do not contain a heterocycle.

[0078] [ka]

[0079] (e) As the heterocycle-containing alkylammonium salt, compounds having the following structures (compounds (e1) to (e3)) are preferred.

[0080] [ka]

[0081] The anticorrosive agent may also be a salt of the above-mentioned compound. Specific examples of the salt include, but are not limited to, sodium salt, potassium salt, ammonium salt, and alkylammonium salt (e.g., tetramethylammonium salt). The anticorrosive agent may also be a hydrate of the above-mentioned compound.

[0082] The concentration of the anticorrosive agent in the treatment solution according to this embodiment is preferably 0.0001 to 10% by mass. The upper limit of the concentration of the anticorrosive agent is more preferably 6% by mass or less, and even more preferably 3% by mass or less. The lower limit of the concentration of the anticorrosive agent is more preferably 0.001% by mass or more, even more preferably 0.01% by mass or more, and still more preferably 0.1% by mass or more. When two or more types of anticorrosive agents are contained, the total amount thereof is preferably within the above range.

[0083] ((E) Organic solvent)

[0084] The treatment liquid according to this embodiment may contain an organic solvent depending on the application and conditions. The treatment liquid according to this embodiment can be suitably used as a treatment liquid containing not only water but also an organic solvent, but in this case, it is more suitable to use an aqueous treatment liquid containing more water than organic solvent.

[0085] Specific examples of organic solvents are not particularly limited, but are preferably at least one selected from the group consisting of alcohol-based solvents, glycol ester-based solvents, sulfoxide-based solvents, sulfone-based solvents, amide-based solvents, lactone-based solvents, imidazolidinone-based solvents, nitrile-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, pyrrolidone-based solvents, and urea-based solvents. Furthermore, the treatment liquid according to this embodiment preferably contains only at least one organic solvent selected from the group consisting of alcohol-based solvents, glycol ester-based solvents, sulfoxide-based solvents, sulfone-based solvents, amide-based solvents, lactone-based solvents, imidazolidinone-based solvents, nitrile-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, pyrrolidone-based solvents, and urea-based solvents, and more preferably does not contain any other types of solvents. Furthermore, when the treatment liquid according to this embodiment contains an organic solvent, it is preferable to use a water-soluble organic solvent from the viewpoint of the water solubility of the treatment liquid.

[0086] Specific examples of alcohol-based solvents include aliphatic alcohols such as methanol, ethanol, denatured ethanol, isopropanol, n-propanol, n-butanol, and 3-methoxy-3-methyl-1-butanol; and glycols such as ethylene glycol (also known as 1,2-ethanediol and monoethylene glycol), diethylene glycol (also known as 2,2'-oxydiethanol and diethyl glycol), propylene glycol (also known as propane-1,2-diol), dipropylene glycol, glycerin, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, furfuryl alcohol, and hexylene glycol (also known as 2-methyl-2,4-pentanediol).

[0087] Specific examples of glycol ester solvents include ethylene glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, ethylene glycol dibutyl ether, diethylene glycol monobutyl ether, diethylene glycol dibutyl ether, triethylene glycol monobutyl ether, triethylene glycol dibutyl ether, ethylene glycol monohexyl ether, ethylene glycol dihexyl ether, diethylene glycol monohexyl ether, diethylene glycol dihexyl ether, and ethylene glycol phenyl ether; ethylene glycol ether acetates such as ethylene glycol monobutyl ether acetate and diethylene glycol monobutyl ether acetate; propylene glycol propylene-based glycol ethers such as propylene glycol monomethyl ether (PGME), propylene glycol dimethyl ether, dipropylene glycol monomethyl ether (DPM), dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol dimethyl ether, propylene glycol monoethyl ether, propylene glycol diethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol diethyl ether, propylene glycol monopropyl ether, propylene glycol dipropyl ether, dipropylene glycol monopropyl ether, dipropylene glycol dipropyl ether, propylene glycol monobutyl ether, propylene glycol dibutyl ether, dipropylene glycol monobutyl ether, dipropylene glycol dibutyl ether, tripropylene glycol monobutyl ether, tripropylene glycol dibutyl ether, and propylene glycol phenyl ether;Examples include propylene-based glycol ether acetates such as propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, and propylene glycol diacetate;

[0088] Specific examples of sulfoxide solvents include dimethyl sulfoxide (DMSO), diethyl sulfoxide, dipropyl sulfoxide, diphenyl sulfoxide, and thiophene.

[0089] Specific examples of sulfone-based solvents include dimethyl sulfone, diethyl sulfone, tetramethylene sulfone, dipropyl sulfone, sulfolane (also known as tetramethylene sulfone), 3-methyl sulfolane, 2,4-dimethyl sulfolane, 3,4-dimethyl sulfolane, diphenyl sulfolane, 3,4-diphenylmethyl sulfolane, sulfolene, 3-methyl sulfolene, and 3-ethyl sulfolene.

[0090] Specific examples of amide solvents include dimethylformamide (DMF), diethylformamide (DEF), dimethylacetamide (DMAc), N-methylpyrrolidine (MPD), and hexamethylphosphoric triamide (HMPA).

[0091] Specific examples of lactone solvents include γ-butyllactone, α-methyl-γ-butyrolactone, β-propiolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, γ-laurolactone, and hexanolactone.

[0092] Specific examples of imidazolidinone solvents include 2-imidazolidinone, 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1,3-dipropyl-2-imidazolidinone, and 1,3-diisopropyl-2-imidazolidinone.

[0093] Specific examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0094] Specific examples of ketone solvents include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone, cyclohexanone, diacetone alcohol, 1-hexanone, 2-hexanone, 4-heptanone, 2-heptanone (methyl amyl ketone), 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetylacetone, acetonylacetone, phenylacetone, acetophenone, methyl naphthyl ketone, methylcyclohexanone, ionone, isophorone, propylene carbonate (propylene carbonate), diacetonyl alcohol, and acetylcarbinol.

[0095] Specific examples of the ether solvent include diisopropyl ether, 1,4-dioxane, methyl tert-butyl ether (MTBE), dimethyl ether, diethyl ether, dipropyl ether, and methyl phenyl ether.

[0096] Specific examples of ester solvents include methyl acetate, ethyl acetate, butyl acetate, amyl acetate, propyl acetate, isopropyl acetate, methyl lactate, ethyl lactate, butyl lactate, ethyl methoxyacetate, ethyl ethoxyacetate, 2-methoxybutyl acetate (2-methoxybutyl acetate), 3-methoxybutyl acetate (3-methoxybutyl acetate), 4-methoxybutyl acetate (4-methoxybutyl acetate), 3-methoxy-3-methylbutyl acetate (3-methoxy-3-methylbutyl acetate), 3-ethyl-3-methoxybutyl acetate (3-ethyl-3-methoxybutyl acetate), 4-methyl-4-methoxy Examples of the alkyl esters include pentyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate, propyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, and propyl 3-methoxypropionate.

[0097] Specific examples of pyrrolidone solvents include N-methylpyrrolidone (NMP), 2-pyrrolidone, and N-vinyl-2-pyrrolidone.

[0098] Specific examples of urea-based solvents include 1,3-dimethylurea, 1,3-diethylurea, 1,3-dipropylurea, 1,3-diisopropylurea, tetramethylurea, tetraethylurea, tetrapropylurea, tetraisopropylurea, and N,N-dimethylpropyleneurea.

[0099] Among the above, the organic solvent is preferably a water-soluble organic solvent. Among the above specific examples, suitable examples of the water-soluble organic solvent include alcohols such as isopropanol, ethanol, ethylene glycol, propylene glycol, glycerin, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, diethylene glycol, dipropylene glycol, furfuryl alcohol, and hexylene glycol (also known as 2-methyl-2,4-pentanediol); glycol ester solvents such as diethylene glycol monobutyl ether and propylene glycol monomethyl ether; dimethyl sulfoxide; ethers such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, and propylene glycol dimethyl ether; and morpholines such as N-methylmorpholine N-oxide. Among these, hexylene glycol (also known as 2-methyl-2,4-pentanediol) is more preferably used.

[0100] Among the above, from the viewpoint of compatibility between water and the organic solvent, alcohols are preferred as the (E) organic solvent, and among alcohols, glycols are more preferred, and among glycols, hexylene glycol is even more preferred.

[0101] The (E) organic solvent may be used alone or in combination of two or more kinds.

[0102] As described above, the content of the organic solvent may be determined taking into consideration conditions such as whether to use an aqueous treatment liquid or an organic solvent-based treatment liquid, and which metal layer is to be protected. For example, as described above, if it is desired to reduce damage to a metal layer such as aluminum (including, for example, alumina), it is preferable to reduce the content of water. In this case, it is preferable to increase the content of organic solvent. On the other hand, if the etching effect on a metal (layer) such as aluminum is not required, the desired effect can be obtained at low cost by increasing the content of water. In such cases, it is preferable to not contain an organic solvent or to reduce the content of organic solvent. In this way, the content of the organic solvent described below may be adjusted to adjust the content of water.

[0103] For example, in a preferred example of an aqueous treatment liquid (a treatment liquid in which the water content is higher than the organic solvent content, or a treatment liquid containing no organic solvent), from the viewpoint of achieving both residue removability and corrosion prevention at an even higher level, the upper limit of the content of the (E) organic solvent is more preferably 40% by mass or less, even more preferably 30% by mass or less, still more preferably 20% by mass or less, and even more preferably 10% by mass or less. Furthermore, the lower limit of the content of the (E) organic solvent may be a value greater than 0% by mass, or may be 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more.

[0104] Use of such organic solvents can further improve the corrosion resistance of layers (e.g., metal wiring layers, etching stop layers, interlayer insulating films, or other functional layers) containing, as a main component, a metal component such as cobalt, copper, tungsten, ruthenium, aluminum (including, for example, alumina), molybdenum, etc. In other words, use of such solvents can further effectively reduce damage (film loss) to layers containing aluminum (including, for example, alumina), cobalt, etc., without impairing the removability of zirconium-based residues.

[0105] The treatment solution according to this embodiment may or may not contain components other than those described above, as necessary. Examples of such components include a pH adjuster, a surfactant, a solvent, etc. Furthermore, the treatment solution according to this embodiment may contain metal impurities, as described below, within a range in which the action and effect of the treatment solution can be obtained.

[0106] (pH adjuster)

[0107] The treatment solution according to this embodiment may contain a pH adjuster to adjust the pH to a desired level. Examples of pH adjusters that can be used include inorganic acids, organic acids, organic basic compounds, and inorganic basic compounds. Examples of pH adjusters include methanesulfonic acid (MSA), acetic acid, sulfuric acid, phosphoric acid, and hydrochloric acid.

[0108] The pH of the treatment liquid according to this embodiment is preferably 2 to 6. A suitable pH can be selected depending on whether the treatment liquid according to this embodiment is an aqueous treatment liquid or an organic solvent-based treatment liquid. For example, in the case of an aqueous treatment liquid, the pH is more preferably 3 to 6. In the case of an aqueous treatment liquid, the lower limit of the pH is more preferably 4 or higher. In the case of an organic solvent-based treatment liquid, the pH is more preferably 2 to 5. In the case of an organic solvent-based treatment liquid, the upper limit of the pH is more preferably 4 or lower.

[0109] (buffering agent)

[0110] 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.

[0111] Examples of buffers include Good's buffers, such as 2-cyclohexylaminoethanesulfonic acid (CHES), 3-cyclohexylaminopropanesulfonic acid (CAPS), N-tris(hydroxymethyl)methyl-3-aminopropanesulfonic acid (TAPS), 4-(cyclohexylamino)-1-butanesulfonic acid (CABS), tricine, bicine, 2-morpholinoethanesulfonic acid monohydrate (MES), bis(2-hydroxyethyl)aminotris(hydroxymethyl)methane (Bis-Tris), N-(2-acetamido)iminodiacetic acid (ADA), piperazine-1,4-bis(2-ethanesulfonic acid) (PIPES), N-(2-acetamido)-2-aminoethanesulfonic acid (ACES), 2-hydroxy-3-morpholinopropanesulfonic acid (M OPSO), N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES), 3-morpholinopropanesulfonic acid (MOPS), N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid (TES), 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (HEPES), 3-[N-tris(hydroxymethyl)methylamino]-2-hydroxypropanesulfonic acid (TAPSO), piperazine-1,4-bis(2-hydroxypropanesulfonic acid) (POPSO), 4-(2-hydroxyethyl)piperazine-1-(2-hydroxypropane-3-sulfonic acid) (HEPSO), 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid (EPPS), and the like.

[0112] The buffering agent may be used alone or in combination of two or more kinds. Alternatively, the treatment liquid according to this embodiment may not contain a buffering agent.

[0113] (surfactant)

[0114] 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.

[0115] 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.

[0116] 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).

[0117] Examples of cationic surfactants include alkylpyridium surfactants and quaternary ammonium salt surfactants.

[0118] Examples of amphoteric surfactants include betaine surfactants, amino acid surfactants, imidazoline surfactants, and amine oxide surfactants.

[0119] These surfactants are generally commercially available. The surfactants may be used alone or in combination of two or more.

[0120] 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 this content is more preferably 0.0002% by mass or more, and even more preferably 0.002% by mass or more. The upper limit of this 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.

[0121] 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.

[0122] (Impurities, etc.)

[0123] 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.

[0124] 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.

[0125] 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.

[0126] The treatment liquid according to this embodiment may contain, for example, impurities derived from organic substances (organic impurities). The total content of the organic impurities in the treatment liquid according to this embodiment is preferably 5000 mass ppm or less. The lower limit of the organic impurity content is preferably as low as possible, and may be, for example, 0.1 mass ppm or more. The total content of organic impurities may be, for example, 0.1 mass ppm to 5000 mass ppm.

[0127] 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, 10,000 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 will be improved (however, the effects of this embodiment are not limited to these).

[0128] The organic impurities and / or the entities to be counted 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).

[0129] 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.

[0130] The treatment liquid 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 described above, it is suitable as a treatment liquid for semiconductor substrates, the semiconductor substrate including a substrate and a film formed on the substrate, the film containing at least one selected from the group consisting of silicon atoms, cobalt atoms, zirconium atoms, and aluminum atoms. It is also suitable for cleaning semiconductor substrates on which a film containing zirconium atoms has been formed, specifically, for cleaning semiconductor substrates on which a film containing at least one selected from the group consisting of zirconium and zirconium alloys has been formed. More specifically, a suitable example of this embodiment is a treatment liquid for semiconductor substrates, the semiconductor substrate including a substrate and a film formed on the substrate, the film containing at least one selected from the group consisting of zirconium and zirconium alloys. A more preferred example is a semiconductor substrate (semiconductor substrate) that includes a substrate, a film containing at least one selected from the group consisting of zirconium and zirconium alloys, and a film containing at least one selected from the group consisting of silicon atoms, cobalt atoms, and aluminum atoms. Such a semiconductor substrate can exhibit the effects and advantages of this embodiment, such as excellent removability of zirconium-based residues and excellent protection of the metal layer to be protected.

[0131] Here, an example of a semiconductor substrate for which the treatment liquid according to this embodiment can be used will be described.

[0132] FIG. 1 is a cross-sectional view showing an example of an element (semiconductor substrate) to be cleaned after dry etching.

[0133] The semiconductor element 100 shown in FIG. 1 includes a substrate 10, a metal wiring layer 20, an etching stop layer 30, and an interlayer insulating film 40 stacked 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).

[0134] This semiconductor element 100 is in a state after dry etching has been performed in a wiring process, i.e., after dry etching of the interlayer insulating film 40 has been performed using the HM layer 50, on which a 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.

[0135] In the spaces between the interlayer insulating films 40 in the wiring pattern, the metal wiring layer 20 is exposed, and dry etching residues 60 are also attached.

[0136] The substrate 10 may be made of a material such as silicon, amorphous silicon, or glass.

[0137] Examples of the metal wiring layer 20 include wiring layers containing metals such as molybdenum (Mo), tungsten (W), ruthenium (Ru), copper (Cu), iron (Fe), nickel (Ni), 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 metal oxides, metal nitrides, metal chlorides, metal fluorides, and the like of these metals.

[0138] 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 various metals mentioned above, as well as their metal oxides, metal nitrides, metal chlorides, and metal fluorides. Examples of silicon-based materials include SiN, SiO2, low-k films (SiOC films, SiCOH films, etc.), and ILDs.

[0139] The material of the interlayer insulating film 40 may be any insulating material, and the material is not particularly limited. A suitable material can be selected taking into consideration manufacturing conditions and the like. Examples of materials that may be contained in the interlayer insulating film 40 include silicon-based materials such as SiO2, SiN, SiOC, and SiOCN. For example, if the etching stop layer 30 is an etching stopper made of alumina oxide or the like, the portion of the etching stop layer 30 located below the interlayer insulating film 40 must be protected from corrosion, while the portion located above the metal wiring layer 20 must be removed. The treatment solution according to this embodiment can achieve both high levels of residue removal and corrosion prevention, and is therefore expected to meet these requirements.

[0140] 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. As the HM layer 50, for example, a layer containing at least one selected from the group consisting of zirconium and zirconium-based alloys can be suitably used. The treatment liquid according to this embodiment is excellent in removing at least zirconium-based residues, and therefore can efficiently remove residues (see dry etching residues 60) generated from the HM layer 50 using such materials. As mentioned above, zirconium-based alloys include zirconium oxide (ZrO x (where x represents a number)) and other zirconium-based alloys can be used.

[0141] The dry etching residue 60 is mainly a Zr-containing residue containing a zirconium-based material derived from the HM layer 50, but is not limited to such a residue. The dry etching residue 60 includes, for example, the above-mentioned etching residue containing inorganic substances.

[0142] <Processing method>

[0143] The treatment solution according to this embodiment can be suitably used as a method for treating a semiconductor substrate. The treatment method according to this embodiment is a method for treating a semiconductor substrate having a protective film, and includes a step of removing impurities from the semiconductor substrate by contacting the protective film with the treatment solution. For example, in the case of a semiconductor element 100 (semiconductor substrate) shown in FIG. 1, the protective film corresponds to the HM layer 50. Hereinafter, cleaning of the semiconductor element 100 shown in FIG. 1 will be described as an example.

[0144] The processing method according to this embodiment is a process of cleaning the semiconductor element 100 after dry etching in the wiring process using the above-described processing solution. The processing method is not particularly limited, and any known processing method can be used.

[0145] When the treatment liquid is brought into contact with the semiconductor element 100 to be cleaned, the treatment liquid may be diluted 2 to 2000 times to obtain a diluted liquid, and then cleaning may be performed using this diluted liquid.

[0146] Examples of cleaning operations include a method of continuously applying a treatment solution onto a semiconductor element 100 rotating at a constant speed (spin coating method), a method of immersing the semiconductor element 100 in a treatment solution for a certain period of time (dip method), and a method of spraying a treatment solution onto the surface of the semiconductor element 100 (spray method).

[0147] 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 20°C or higher, and even more preferably 40°C or higher. The upper limit of the cleaning treatment temperature (temperature of the treatment liquid) is more preferably 75°C or lower, and even more preferably 70°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.

[0148] 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 semiconductor element 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, even more preferably 10 minutes or less, and even more preferably 5 minutes or less.

[0149] Since cleaning is performed using the treatment solution according to this embodiment, in a semiconductor element 100 having dry etching residues 60, 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. In particular, when the HM layer 50 contains zirconium and / or a zirconium alloy, the treatment solution according to this embodiment is particularly suitable because of its excellent ability to remove zirconium-based residues.

[0150] In addition, by using the treatment liquid according to this embodiment, damage to various functional layers (metal wiring layer 20, etching stop layer 30, interlayer insulating film 40, etc.) other than the protective film can also be suppressed.

[0151] Furthermore, the treatment solution according to this embodiment can provide a practical level of cleaning effect without using conventional general-purpose hydroxylamine or the like, and therefore can be expected to have the advantage of enabling the manufacture of semiconductor devices and the like to be carried out more safely.

[0152] <Semiconductor manufacturing method>

[0153] The treatment solution according to this embodiment and the cleaning method using the same can be suitably used in a semiconductor manufacturing method. The semiconductor manufacturing method according to this embodiment is a semiconductor manufacturing method including, for example, the steps of: (1) preparing a semiconductor substrate having a substrate and a protective film formed on the substrate; (2) etching using the protective film; and (3) removing impurities from the semiconductor substrate after etching by contacting the treatment solution with the semiconductor substrate. As with the explanation of the cleaning method, the protective film corresponds to, for example, the HM layer 50 in the case of the semiconductor element 100 (semiconductor substrate) shown in FIG. 1. The following explanation will be given taking the cleaning of the semiconductor element 100 shown in FIG. 1 as an example.

[0154] (1) A step of preparing a semiconductor substrate having a substrate and a protective film provided on the substrate.

[0155] In step (1), a semiconductor substrate having a substrate and a protective film formed on the substrate 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) having, 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 the protective film is prepared.

[0156] The method for sequentially stacking the substrate 10, 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.

[0157] (2) Etching process using a protective film

[0158] Next, etching is performed using a protective film. Taking the interlayer insulating film 40 as an example, the portions protected by the protective film are not removed, while the portions not protected by the protective film are removed. Therefore, etching can be performed using the protective film in this manner. The etching method is not particularly limited, and either wet etching or dry etching may be used, but dry etching is preferred. Dry etching is advantageous in that it allows metal wiring at the nano-level and allows for control of the gas used. Furthermore, dry etching can be considered to cause relatively large damage to the substrate 10, etc. However, the use of the treatment solution according to this embodiment is desirable in that such damage can be effectively suppressed, thereby more effectively utilizing the advantages of this embodiment.

[0159] In the case of dry etching, plasma can be used. Usually, when performing plasma etching, there are problems such as the substrate 10 being easily damaged and the plasma etching residues that are generated and need to be cleaned with a processing liquid. However, the use of the processing liquid according to this embodiment is preferable in that such problems can be effectively suppressed.

[0160] (3) After etching, the process of removing impurities from the semiconductor substrate by bringing the above-mentioned treatment liquid into contact with the semiconductor substrate.

[0161] The cleaning method described above can be used in step (3), thereby obtaining the semiconductor device 100. If necessary, known post-treatment can be performed after cleaning.

[0162] 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 being able to efficiently remove zirconium-based residues and having excellent corrosion resistance. For example, the treatment liquid according to this embodiment can more efficiently remove residues generated during dry etching of a substrate having a hard mask layer (HM layer) mainly composed of at least one selected from the group consisting of zirconium and zirconium-based alloys than conventional treatment liquids.

[0163] Conventionally used treatment solutions, such as those containing hydrogen fluoride, hydroxylamine, and hydrogen peroxide, can cause significant damage to the film to be protected (i.e., significant film loss), making it difficult to achieve both residue removal and corrosion prevention. However, the treatment solution according to the present embodiment can effectively suppress such problems. For example, it is expected to reduce damage to substrates, metal wiring, etching stop layers, interlayer insulating films, and various other functional layers containing silicon compounds such as Si and SiN, tungsten, molybdenum, ruthenium, copper, cobalt, and the like as metal components. Therefore, it is quite possible to create a treatment solution that is particularly excellent in removing zirconium-based residues and in preventing corrosion of versatile metal materials such as silicon compounds, tungsten, molybdenum, ruthenium, copper, and cobalt.

[0164] The treatment liquid according to this embodiment can achieve a sufficient effect even if it does not contain hydrogen peroxide. Furthermore, the treatment liquid according to this embodiment can achieve a sufficient effect even if it does not contain hydroxylamine. Furthermore, the treatment liquid according to this embodiment can achieve a sufficient effect even if it does not contain tetramethylammonium hydroxide (TMAH) and / or tetraethylammonium hydroxide (TEAH). From this perspective, the treatment liquid according to this embodiment may be a treatment liquid that does not contain hydrogen peroxide. The treatment liquid according to this embodiment may be a treatment liquid that does not contain hydroxylamine. The treatment liquid according to this embodiment may be a treatment liquid that does not contain tetramethylammonium hydroxide (TMAH). The treatment liquid according to this embodiment may be a treatment liquid that does not contain tetraethylammonium hydroxide (TEAH). [Example]

[0165] 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.

[0166] 1. Test 1

[0167] 1-1. Preparation of processing solution

[0168] <Comparative Example 1-1, Examples 1-1 to 1-3> Treatment solutions having the compositions shown in Table 1 were prepared. For example, Example 1-1 was an aqueous treatment solution containing only 0.01 mass% hydrogen fluoride (HF), 0.01 mass% KCl, and the remainder 99.98 mass% water. The treatment solution of Example 1-1 had a pH of 2.86 and a high concentration of potassium ions (K + The concentration of ) was 0.01% by mass. For example, Comparative Example 1-1 was an aqueous treatment solution containing only 0.01 mass % of hydrogen fluoride (HF) and the remainder being 99.99 mass % of water. The treatment solution of Comparative Example 1-1 had a pH of 2.81 and a high concentration of potassium ions (K + The concentration of ) was 0% by mass.

[0169] <Method for measuring pH of treatment solution> 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).

[0170] 1-2. Evaluation of zirconium-based residue removal (residue removal)

[0171] The removability of zirconium-based residues in each of the Examples and Comparative Examples was evaluated by the following method.

[0172] First, laminates (substrates having films) each including a metal layer were prepared as follows. A stack was prepared by depositing a metal layer (15 nm thick) of Zr oxide (ZrOx) on a substrate (12-inch silicon substrate) using the CVD method.

[0173] Next, each obtained laminate (substrate with film) was cut into a 2 cm x 2 cm piece in top view to obtain a test sample (wafer coupon). Then, 80 mL of the treatment solution for each Example and Comparative Example was placed in a 100 mL cup. The sample was then placed in the treatment solution at a temperature of 50°C for 30 minutes. The treatment solution was stirred at 300 rpm during immersion. After immersion, the sample was removed from the treatment solution, washed with water at room temperature for 30 seconds, and dried with nitrogen.

[0174] The etching rate (Å / min) was measured to evaluate the amount of film loss after treatment. x It was determined that the higher the etching rate, the greater the effect of removing zirconium-based residues.

[0175] 1-3.Evaluation of corrosion resistance

[0176] The corrosion resistance of each example and each comparative example was evaluated by the following method.

[0177] First, laminates (substrates having films) each including a metal layer were prepared as follows. A laminate was prepared by depositing a metal layer of SiN (20 nm thick) on a substrate (12-inch silicon substrate) using the CVD method. A laminate was prepared by forming a Co metal layer (80 nm thick) on a substrate (12-inch silicon substrate) by sputtering.

[0178] Next, each obtained laminate (substrate with film) was cut into a 2 cm x 2 cm piece in top view to obtain a test sample (wafer coupon). Then, 80 mL of the treatment solution for each Example and Comparative Example was placed in a 100 mL cup. The sample was then placed in the treatment solution at a temperature of 50°C for a predetermined time. The immersion time for the SiN metal layer laminate was 15 minutes, and the immersion time for the Co metal layer laminate was 15 minutes. During immersion, the treatment solution was stirred at 300 rpm. After immersion, the sample was removed from the treatment solution, rinsed with water at room temperature for 30 seconds, and dried with nitrogen.

[0179] The etching rate (Å / min) was measured to evaluate the amount of film loss after the treatment. In the case of the SiN and Co metal layers, it was determined that the lower the etching rate of the metal layer, the more effectively the damage to the metal layer was suppressed.

[0180] The composition and evaluation results of the treatment liquid for each example and comparative example are shown in Table 1. In the table, "-" indicates that the component in question was not added.

[0181] [Table 1]

[0182] HF: Hydrogen fluoride, KCl: Potassium chloride, DIW: Deionized water

[0183] As shown in Table 1, it was at least confirmed that, compared to Comparative Example 1-1, each Example in Table 1 was able to sufficiently remove zirconium-based residues and also sufficiently suppress damage to the metal species whose etching rates were measured.

[0184] 2. Test 2

[0185] 2-1. Preparation of treatment solution

[0186] <Comparative Example 2-1, Examples 2-1 to 2-6> Treatment solutions having the compositions shown in Table 2 were prepared. For example, Example 2-2 was an aqueous treatment solution containing only 0.1 mass% hydrogen fluoride (HF), 0.1 mass% potassium chloride (KCl) as a metal salt, 0.55 mass% 2-(aminomethyl)tetrahydrofuran (THF amine), 0.5 mass% 5-amino-1H-tetrazole (5am.Tet.), 0.1 mass% polyvinylpyrrolidone (PVP K90), and the remainder 98.65 mass% water (deionized water: DIW). The treatment solution of Example 2-2 had a pH of 4.83 and contained 0.1 mass% potassium ions (K + The concentration of THF amine and PVP K90 was 0.1% by mass. THF amine and PVP K90 were used as anticorrosive agents expected to have anticorrosive effects. For example, Comparative Example 2-1 was an aqueous treatment solution containing only 0.1% by mass of hydrogen fluoride (HF), 0.55% by mass of 2-(aminomethyl)tetrahydrofuran (THF amine), 0.5% by mass of 5-amino-1H-tetrazole (5am.Tet.), and the remainder being 98.85% by mass of water (deionized water: DIW). This treatment solution of Comparative Example 2-1 had a pH of 4.9 and a concentration of alkali metal ions of 0% by mass.

[0187] <Method for measuring pH of treatment solution> The pH of the treatment solution was measured in the same manner as in "1. Test 1" above.

[0188] 2-2. Evaluation of zirconium-based residue removal (residue removal)

[0189] Test samples were prepared in the same manner as in "1. Test 1" above, "1-2. Evaluation of zirconium-based residue removability (residue removability)." The etching rate of the sample was measured in the same manner as in "1-2. Evaluation of zirconium-based residue removability (residue removability)." x The removal of ZrO x It was determined that the higher the etching rate, the greater the effect of removing zirconium-based residues.

[0190] 2-3.Evaluation of corrosion resistance

[0191] Test samples were prepared and their corrosion resistance was evaluated in the same manner as in "1. Test 1" "1-3. Evaluation of corrosion resistance." That is, in the case of SiN and Co metal layers, it was determined that the lower the etching rate of the metal layer, the more effectively damage to the metal layer was suppressed.

[0192] The composition and evaluation results of the treatment liquid for each example and comparative example are shown in Table 2. In the table, "-" indicates that the component in question was not added.

[0193] [Table 2]

[0194] HF: hydrogen fluoride, THF amine: 2-(aminomethyl)tetrahydrofuran, 5am.Tet.: 5-amino-1H-tetrazole, KCl: potassium chloride, LiCl: lithium chloride, NaCl: sodium chloride, KBr: potassium bromide, KI: potassium iodide, PVP K90: polyvinylpyrrolidone, DIW: deionized water

[0195] As shown in Table 2, it was at least confirmed that, compared to Comparative Example 2-1, each Example in Table 2 was able to sufficiently remove zirconium-based residues and also sufficiently suppress damage to the metal species for which the etching rate was measured.

[0196] 3. Test 3

[0197] 3-1. Preparation of treatment solution

[0198] <Comparative Example 3-1, Examples 3-1 to 3-10> Treatment solutions having the compositions shown in Table 3 were prepared. For example, Example 3-1 was an aqueous treatment solution containing only 0.1 mass% hydrogen fluoride (HF), 0.1 mass% potassium chloride (KCl) as a metal salt, 0.55 mass% 2-(aminomethyl)tetrahydrofuran (THF amine), 0.5 mass% 5-amino-1H-tetrazole (5am.Tet.), 0.1 mass% polyvinylpyrrolidone (PVP K90), and the remainder 98.65 mass% water (deionized water: DIW). The treatment solution of Example 3-1 had a pH of 4.89 and contained 0.1 mass% potassium ions (K + The concentration of THF amine and PVP K90 was 0.1% by mass. THF amine and PVP K90 were used as anticorrosive agents expected to have anticorrosive effects.

[0199] <Method for measuring pH of treatment solution> The pH of the treatment solution was measured in the same manner as in "1. Test 1" above.

[0200] 3-2. Evaluation of zirconium-based residue removal (residue removal)

[0201] Test samples were prepared in the same manner as in "1. Test 1" above, "1-2. Evaluation of zirconium-based residue removability (residue removability)." The etching rate of the sample was measured in the same manner as in "1-2. Evaluation of zirconium-based residue removability (residue removability)." x The removal of ZrO x It was determined that the higher the etching rate, the greater the effect of removing zirconium-based residues.

[0202] 3-3.Evaluation of corrosion resistance

[0203] First, laminates (substrates having films) each including a metal layer were prepared as follows. A laminate was prepared by depositing a metal layer of SiN (20 nm thick) on a substrate (12-inch silicon substrate) using the CVD method. A laminate was prepared by forming a Co metal layer (80 nm thick) on a substrate (12-inch silicon substrate) by sputtering. A laminate was prepared by depositing a metal layer of Al2O3 (20 nm thick) on a substrate (12-inch silicon substrate) using the CVD method.

[0204] Next, each obtained laminate (substrate with film) was cut into a 2 cm x 2 cm piece in top view to obtain a test sample (wafer coupon). Then, 80 mL of the treatment solution for each Example and Comparative Example was placed in a 100 mL cup. The sample was then placed in the treatment solution at a temperature of 58°C for a predetermined time. The immersion time was 30 minutes for the SiN metal layer laminate, 10 minutes for the Co metal layer laminate, and 5 minutes for the Al2O3 metal layer laminate. The treatment solution was stirred at 300 rpm during immersion. After immersion, the sample was removed from the treatment solution, rinsed with water at room temperature for 30 seconds, and dried with nitrogen.

[0205] The etching rate (Å / min) was measured to evaluate the amount of film loss after treatment. In the case of the metal layers of SiN, Co, and Al2O3, it was determined that the lower the etching rate of the metal layer, the more effectively the damage to the metal layer was suppressed.

[0206] The compositions and evaluation results of the treatment solutions for each example and comparative example are shown in Table 3. In the table, "-" means that the component in question was not added, and "no data" means that no experiments were conducted on the metal in question.

[0207] [Table 3]

[0208] HF: hydrogen fluoride, THF amine: 2-(aminomethyl)tetrahydrofuran, 5am.Tet.: 5-amino-1H-tetrazole, KCl: potassium chloride, PVP K90: polyvinylpyrrolidone, DIW: deionized water

[0209] As shown in Table 3, it was at least confirmed that each Example in Table 3 was able to sufficiently remove zirconium-based residues and sufficiently suppress damage to the metal species for which the etching rate was measured, compared to Comparative Example 3-1.

[0210] From the above, it was confirmed that the treatment solution according to this example can efficiently remove zirconium-based residues and has excellent corrosion prevention properties. Such a treatment solution can be suitably used in a method for cleaning semiconductor substrates and a method for manufacturing semiconductors.

[0211] This application claims priority to U.S. Provisional Application No. 63 / 557,136, filed with the U.S. Patent and Trademark Office on February 23, 2024, the contents of which are incorporated herein by reference. [Explanation of symbols]

[0212] 10: Circuit board 20: Metal wiring layer 30: Etch stop layer 40: Interlayer insulating film 50: Hard mask layer (HM layer) 60: Dry etching residue 100: Semiconductor element

Claims

1. (A) a compound capable of releasing fluoride ions; (B) at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, and ions of elements in Group III of the periodic table; (C) water; A processing solution comprising:

2. The concentration of the ions in the component (B) is 0.0005 to 0.5% by mass. The treatment liquid according to claim 1 .

3. Further, (D) an anticorrosive agent is contained. The treatment liquid according to claim 1 .

4. Further, (E) an organic solvent is contained. The treatment liquid according to claim 1 .

5. The (D) anticorrosion agent contains a nitrogen-containing heterocycle-containing compound or a salt thereof, The treatment liquid according to claim 3 .

6. The (E) organic solvent contains at least one selected from the group consisting of alcohol-based solvents, glycol ester-based solvents, sulfoxide-based solvents, sulfone-based solvents, amide-based solvents, lactone-based solvents, imidazolidinone-based solvents, nitrile-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, pyrrolidone-based solvents, and urea-based solvents. The treatment liquid according to claim 4.

7. The content of the water (C) is 0.1 to 99.999 mass%. The treatment liquid according to claim 1 .

8. pH is 2 to 6; The treatment liquid according to claim 1 .

9. the processing liquid is a processing liquid for semiconductor substrates, The semiconductor substrate includes a substrate and a film formed on the substrate; the film contains at least one selected from the group consisting of silicon atoms, cobalt atoms, zirconium atoms, and aluminum atoms; The treatment liquid according to claim 1 .

10. A method for treating a semiconductor substrate having a protective film, comprising: A method for treating a semiconductor substrate, comprising the step of removing impurities from the semiconductor substrate by bringing the treatment liquid according to claim 1 into contact with the protective film.

11. providing a semiconductor substrate having a substrate and a protective film disposed on the substrate; Etching using the protective film; a step of removing impurities from the semiconductor substrate by bringing the treatment liquid according to claim 1 into contact with the semiconductor substrate after the etching.

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