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

Abstract

To provide a processing solution capable of efficiently removing titanium-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) organic solvent, 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. Examples of materials for the mask layer include titanium, titanium nitride (TiN), and titanium oxide (TiO x (x represents a number)) and other titanium alloys 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 extensive research into treatment solutions such as hydrogen fluoride and have found that there is room for improvement in terms of both removing titanium-based residues (residues containing titanium or titanium-based alloys) and providing corrosion protection. For example, using a treatment solution such as hydrogen fluoride to remove residues can result in problems such as damage to various metal layers that need 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 titanium-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 titanium-based residues and has excellent corrosion prevention properties, as well as a method for cleaning semiconductor substrates and a method for manufacturing semiconductors that use the same. [Means for solving the problem]

[0009] As a result of extensive research into achieving 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) an organic solvent, has been developed, leading to the completion of 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) an organic solvent. <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) water 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 (C) 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) organic solvent 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, titanium atoms, cobalt 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 titanium-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) an organic solvent. By using such a treatment liquid, titanium-based residues can be efficiently removed and excellent corrosion resistance can be achieved. The titanium-based residue refers to residues containing titanium or titanium-based alloys. The titanium-based alloy refers to a form in which other metal elements or non-metal elements are bonded to titanium, which will be described in detail later. Examples of titanium-based alloys include titanium nitride (TiN), titanium oxide (TiO), and titanium carbide (TiO). x (x represents a number)), titanium oxynitride (TiON), titanium oxyfluoride (TiOF), etc. are exemplified.

[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, the treatment liquid according to this embodiment can efficiently remove etching residues containing such inorganic substances.

[0019] More specifically, the treatment solution according to this embodiment can efficiently remove titanium-based residues (residues containing titanium or titanium-based 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, as well as 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 titanium-based residues (residues containing titanium or titanium-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, titanium-based residues that adhere to semiconductor substrates after dry etching have high wet resistance and are difficult to remove by cleaning processes. 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 titanium.

[0028] First, in dry etching using metal oxides or metal nitrides such as titanium 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 titanium-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 titanium-based metal residue removal and corrosion protection for the metal layer. Similar problems can also occur with silicon-based materials that are susceptible to hydrogen fluoride damage, such as SiN, SiO2, low-k films (e.g., SiOC films and SiCOH films), and ILDs.

[0033] However, the treatment solution according to this embodiment, by using component (A) and component (B) in combination, is excellent in removing titanium-based metal residues without using a high concentration of component (A). As a result, damage to the metal layer and silicon-based material can be suppressed, and both the ability to remove titanium-based metal residues and the ability to prevent corrosion of the metal layer and 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 liquid 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 titanium-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, even 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 titanium-based residues and suppression of damage to the metal layer during the cleaning process. For example, the treatment solution according to this embodiment can maintain a high level of removability of titanium-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, titanium-based residues can be sufficiently and 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) Organic solvent)

[0050] The treatment liquid according to this embodiment contains an organic solvent. The treatment liquid according to this embodiment can be suitably used as an organic solvent-based treatment liquid (a treatment liquid in which the organic solvent content is higher than the water content, or a treatment liquid that does not contain water). As will be described later, the treatment liquid may contain not only an organic solvent but also water, and even in this case, it can be suitably used as an organic solvent-based treatment liquid that contains more organic solvent than water.

[0051] 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.

[0052] 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).

[0053] 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;

[0054] Specific examples of sulfoxide solvents include dimethyl sulfoxide (DMSO), diethyl sulfoxide, dipropyl sulfoxide, diphenyl sulfoxide, and thiophene.

[0055] 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.

[0056] Specific examples of amide solvents include dimethylformamide (DMF), diethylformamide (DEF), dimethylacetamide (DMAc), N-methylpyrrolidine (MPD), and hexamethylphosphoric triamide (HMPA).

[0057] 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.

[0058] 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.

[0059] Specific examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] Specific examples of pyrrolidone solvents include N-methylpyrrolidone (NMP), 2-pyrrolidone, and N-vinyl-2-pyrrolidone.

[0064] 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.

[0065] 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.

[0066] Among the above, from the viewpoint of compatibility with other components, alcohols are preferred as the organic solvent (C), among alcohols, glycols are more preferred, and among glycols, hexylene glycol is even more preferred.

[0067] The (C) organic solvent may be used alone or in combination of two or more kinds.

[0068] The content of the (C) organic solvent in the treatment liquid according to this embodiment is not particularly limited, but is preferably 0.1 to 99.999 mass %. When the content of the (C) organic solvent is high, the treatment liquid can be suitably used as a so-called organic solvent-based treatment liquid, but the content of the organic solvent can also be selected according to the application, taking into consideration the type of metal to be cleaned, etc.

[0069] Furthermore, when (E) water, which will be described later, is also used in combination, the ratio of the organic solvent to water content may be selected according to the application, taking into consideration the type of metal to be cleaned, etc. For example, when using the treatment liquid according to this embodiment to reduce damage to metals such as aluminum (including, for example, alumina), it is preferable to reduce the water content. Furthermore, when reducing damage to metals (layers) such as aluminum, it is preferable to increase the organic solvent content. Furthermore, when reducing damage to metals (layers) such as aluminum, it is preferable that the organic solvent content be higher than the water content. In this way, it may be possible to adjust the organic solvent and water content according to the purpose, taking into consideration the type of metal to be cleaned, etc.

[0070] In this embodiment, the lower limit of the organic solvent content is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, still more preferably 80% by mass or more, and even more preferably 85% by mass or more. The upper limit of the organic solvent content may be 99.9% by mass or less, 99.5% by mass or less, or 99% by mass or less.

[0071] 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 metal components such as cobalt, copper, tungsten, ruthenium, aluminum (including, for example, alumina), molybdenum, etc. as their main components. In other words, use of such solvents can more effectively reduce damage (film loss) to layers containing aluminum (including, for example, alumina), cobalt, etc., without impairing the removability of titanium-based residues.

[0072] ((D) Corrosion inhibitor)

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] Specific examples of the phenanthroline ring-containing compound include 1,10-phenanthroline.

[0081] 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.

[0082] Specific examples of the pyrazole ring-containing compound include 3,5-dimethylpyrazole, 3-amino-5-methylpyrazole, 4-methylpyrazole, and 3-amino-5-hydroxypyrazole.

[0083] Specific examples of purine ring-containing compounds include purine.

[0084] Specific examples of lactam ring-containing compounds include polyvinylpyrrolidone (PVP).

[0085] 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.

[0086] Specific examples of the aliphatic amine compound include alkylamines, dialkylamines, and trialkylamines.

[0087] 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.

[0088] 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.

[0089] (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):

[0090] [ka]

[0091] 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)).

[0092] [ka]

[0093] 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)).

[0094] [ka]

[0095] (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.

[0096] [ka]

[0097] (e) As the heterocycle-containing alkylammonium salt, compounds having the following structures (compounds (e1) to (e3)) are preferred.

[0098] [ka]

[0099] 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.

[0100] 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.

[0101] 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 anticorrosive agents, pH adjusters, surfactants, solvents, 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.

[0102] ((E)Wed)

[0103] The treatment liquid according to this embodiment may further contain (E) water, as needed. As (E) water, for example, deionized water (DIW) can be used, from the viewpoint that it is suitable for manufacturing semiconductor devices.

[0104] 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.

[0105] For example, as described above, if 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, if it is desired to improve the etching effect of a metal (layer) such as aluminum, 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, if it is desired to reduce the water content, the content of the organic solvent can be increased. From this perspective, if the substrate to be processed has an aluminum-containing layer such as alumina, a treatment liquid with a low water content or a treatment liquid containing no water can be used. On the other hand, if the substrate to be processed does not have an aluminum-containing layer such as alumina, a treatment liquid containing an appropriate amount of water can be used from the perspective of cost, etc. In this way, it may be possible to selectively use an organic solvent-based treatment liquid (a treatment liquid in which the organic solvent content is higher than the water content, or a treatment liquid containing no water) and an aqueous treatment liquid depending on the purpose. From this perspective, an organic solvent-based treatment liquid (a treatment liquid in which the organic solvent content is higher than the water content, or a treatment liquid containing no water) can be exemplified as a suitable example of the treatment liquid according to this embodiment.

[0106] Generally, when water is contained in an organic solvent-based treatment liquid (a treatment liquid in which the organic solvent content is higher than the water content, or a treatment liquid containing no water), from the viewpoint of achieving both residue removability and corrosion prevention at an even higher level, the lower limit of the content of (E) water is more preferably 0.1% by mass or more, even more preferably 1% by mass or more, and still more preferably 5% by mass or more. Also, the upper limit of the content of (E) water is more preferably less than 50% by mass, even more preferably 40% by mass or less, still more preferably 30% by mass or less, still more preferably 20% by mass or less, and still more preferably 15% by mass or less.

[0107] (pH adjuster)

[0108] 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.

[0109] The pH of the treatment liquid according to this embodiment is preferably 2 to 6. The pH can be selected appropriately depending on the type of solvent (organic solvent, water) in the treatment liquid according to this embodiment. For example, 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 lower limit of the pH is more preferably 4 or less. Furthermore, 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 more.

[0110] (buffering agent)

[0111] 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.

[0112] 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.

[0113] 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.

[0114] (surfactant)

[0115] 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.

[0116] 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.

[0117] 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).

[0118] Examples of cationic surfactants include alkylpyridium surfactants and quaternary ammonium salt surfactants.

[0119] Examples of amphoteric surfactants include betaine surfactants, amino acid surfactants, imidazoline surfactants, and amine oxide surfactants.

[0120] These surfactants are generally commercially available. The surfactants may be used alone or in combination of two or more.

[0121] 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.

[0122] 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.

[0123] (Impurities, etc.)

[0124] 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.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] 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).

[0129] 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).

[0130] 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.

[0131] 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, cobalt atoms, and aluminum atoms. Furthermore, it is suitable for cleaning semiconductor substrates on which a film containing titanium atoms is 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 is formed. More specifically, a suitable 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 suitable 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, cobalt atoms, and aluminum 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.

[0132] Here, an example of a semiconductor substrate for which the treatment liquid according to this embodiment can be used will be described.

[0133] FIG. 1 is a cross-sectional view showing an example of an element (semiconductor substrate) to be cleaned after dry etching.

[0134] 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).

[0135] 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.

[0136] 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.

[0137] The substrate 10 may be made of a material such as silicon, amorphous silicon, or glass.

[0138] 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.

[0139] 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.

[0140] 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.

[0141] 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 titanium and titanium-based alloys can be suitably used. The treatment liquid according to this embodiment is excellent in 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. As mentioned above, titanium-based alloys include titanium nitride (TiN), titanium oxide (TiO x (x represents a number)), titanium-based materials such as titanium oxynitride (TiON), titanium oxyfluoride (TiOF), etc. can be used.

[0142] The dry etching residue 60 is primarily a Ti-containing residue containing a titanium-based material 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.

[0143] <Processing method>

[0144] 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.

[0145] 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.

[0146] 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.

[0147] 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).

[0148] 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.

[0149] 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.

[0150] 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 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.

[0151] 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.

[0152] 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.

[0153] <Semiconductor manufacturing method>

[0154] 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.

[0155] (1) A step of preparing a semiconductor substrate having a substrate and a protective film provided on the substrate.

[0156] 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.

[0157] 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.

[0158] (2) Etching process using a protective film

[0159] 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.

[0160] 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.

[0161] (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. 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, 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 titanium-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) primarily composed of at least one selected from the group consisting of titanium and titanium-based alloys.

[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 terms of titanium-based residue removal and corrosion prevention for 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 Examples 1-1 to 1-5, Example 1-1> Treatment solutions having the compositions shown in Table 1 were prepared. For example, Example 1-1 was a solvent-based treatment solution containing only 0.01 mass% hydrogen fluoride (HF), 0.015 mass% potassium hydroxide (KOH), 0.4 mass% 5-methyl-1H-benzotriazole (5MBTA), 0.026 mass% methanesulfonic acid (MSA), 9.55 mass% water (deionized water: DIW), and the remainder 90 mass% hexylene glycol (HG). The treatment solution of Example 1-1 had a pH of 3.43 and contained 100% potassium ions (K + The concentration of 5MBTA was 0.015% by mass. 5MBTA was used as an anticorrosive agent to prevent corrosion, and MSA was used as a pH adjuster to adjust the treatment solution to a desired pH. For example, Comparative Example 1-1 was a solvent-based treatment solution containing 0.01 mass% hydrogen fluoride (HF), 0.4 mass% 5MBTA, 9.59 mass% water, and the remainder 90 mass% hexylene glycol (HG). The treatment solution of Comparative Example 1-1 had a pH of 4.31 and a potassium ion concentration of 0 mass%. Note that, since pH adjustment was not required for Comparative Example 1-1, no MSA was added.

[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 titanium residue removal (residue removal)

[0171] The removability of titanium-based residues in each of the Examples and Comparative Examples was evaluated by the following method (evaluation based on residue removal time).

[0172] First, a laminate (substrate with a film) was prepared by using a CVD method. The laminate consisted of a third layer (metal wiring layer, cobalt), an etching stop layer (aluminum oxide), a second layer (interlayer insulating film), and a first layer (metal hard mask layer, titanium oxide: 50 nm thick) stacked in this order on a substrate (12-inch silicon substrate) in a cross-sectional view (substrate / third layer / etching stop layer / second layer / first layer). Test samples were prepared by cutting this laminate into 2 cm x 2 cm pieces in a top view.

[0173] Next, the obtained sample (laminate) was subjected to plasma etching using the first layer as a mask, and the second layer was etched until the surface of the third layer was exposed, forming a hole (diameter / shape: 40 nm / hole-shaped), thereby producing a measurement substrate (etched sample) having the configuration shown in Figure 1 (see Figure 1).

[0174] The etched samples (measurement substrates) were then cleaned. The cleaning was performed as follows: First, the treatment solution of each Example and Comparative Example was heated to 58°C. The etched samples were then immersed in the treatment solution of each Example and Comparative Example at 58°C. The samples were then removed from the treatment solution, washed with isopropyl alcohol, and dried by nitrogen blowing. The remaining residue on the samples was then confirmed using a scanning electron microscope (SEM, imaging magnification: 100kx, model name "SU-8220," manufactured by Hitachi High-Technologies Corporation). Specifically, the residue removability was evaluated by measuring the time required for etching residues (titanium-based residues) to disappear from the hole wall surface. It was determined that the shorter the residue removal time, the better the residue removability.

[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 stack was prepared by depositing a Co metal layer (20 nm thick) on a substrate (12-inch silicon substrate) using the CVD method. 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.

[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 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.

[0179] 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.

[0180] Table 1 shows the compositions of the treatment solutions of the examples and comparative examples and the evaluation results.

[0181] [Table 1]

[0182] HF: hydrogen fluoride, 5MBTA: 5-methyl-1H-benzotriazole, HG: hexylene glycol, MSA: methanesulfonic acid, KOH: potassium hydroxide, DIW: deionized water

[0183] As shown in Table 1, it was at least confirmed that Example 1-1 in Table 1 was able to sufficiently remove titanium-based residues and also sufficiently suppress damage to the metal species for which the etching rate was measured.

[0184] 2. Test 2

[0185] 2-1. Preparation of treatment solution

[0186] <Comparative Examples 2-1 to 2-3, Examples 2-1 to 2-3> Treatment solutions having the compositions shown in Table 2 were prepared. For example, Example 2-1 was an organic solvent-based treatment solution containing only 0.01 mass% hydrogen fluoride (HF), 0.02 mass% potassium chloride (KCl), 0.4 mass% 5-methyl-1H-benzotriazole (5MBTA), 9.57 mass% water (deionized water: DIW), and the remainder 90 mass% hexylene glycol (HG). The treatment solution of Example 2-1 had a pH of 3.4 and contained 100% potassium ions (K + The concentration of 5MBTA was 0.02% by mass. 5MBTA was used as a corrosion inhibitor, with the expectation of corrosion prevention effects. For example, Comparative Example 2-2 was an aqueous treatment solution containing 0.01 mass % of hydrogen fluoride (HF), 0.4 mass % of 5MBTA, and the remainder being 99.59 mass % of water. The treatment solution of Comparative Example 2-2 had a pH of 3 and contained 0.01 mass % of hydrogen fluoride (HF), 0.4 mass % of 5MBTA, and the remainder being 99.59 mass % of water. + The concentration of ) was 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 titanium residue removability (etching residue removability)

[0189] A test sample was prepared in the same manner as in "1. Test 1" above, "1-2. Evaluation of removability of titanium-based residue (residue removability)." Etching was then carried out in the same manner as in "1-2. Evaluation of removability of titanium-based residue (residue removability)," to obtain an etched sample (measurement substrate).

[0190] Next, the etched samples (measurement substrates) were cleaned. Cleaning was performed by the following method. First, the treatment solution of each Example and Comparative Example was heated to 58°C. Next, the etched samples were immersed in the treatment solution of each Example and Comparative Example at 58°C for 3 minutes. After that, the samples were pulled out of the treatment solution, washed with isopropyl alcohol, and then dried by nitrogen blowing. The remaining residue on the samples was then confirmed using a scanning electron microscope (SEM, imaging magnification: 100kx, instrument name "SU-8220", manufactured by Hitachi High-Technologies Corporation). Specifically, the residue removability was evaluated by confirming whether or not etching residues (titanium-based residues) were present on the hole wall surfaces. The residue removability was evaluated based on the following criteria. Note that no corrosion to a practically problematic extent was observed on the metal layers of the measurement substrates of each Example.

[0191] The criteria for judging the residue removability are as follows:

[0192] A: The residues confirmed by SEM before immersion were confirmed by SEM after immersion under the same conditions, and more than 95% of them were removed. B: The residue confirmed by SEM before immersion was confirmed by SEM after immersion under the same conditions, and 85% or more but less than 95% was found to have been removed. C: The residue confirmed by SEM before immersion was confirmed by SEM after immersion under the same conditions, and 80% or more but less than 85% was found to have been removed. D: The residues observed by SEM before immersion were examined by SEM under the same conditions after immersion, and it was found that less than 80% of the residues had been removed.

[0193] 2-3.Evaluation of corrosion protection (film loss)

[0194] Test samples were prepared in the same manner as in "1. Test 1" "1-3. Evaluation of corrosion resistance" above, and corrosion resistance was evaluated by measuring the etching rates of SiN, Co, and Al2O3. 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 damage to the metal layer was suppressed.

[0195] Table 2 shows the composition of the treatment liquid and the evaluation results of each example.

[0196] [Table 2]

[0197] HF: hydrogen fluoride, KCl: potassium chloride, 5MBTA: 5-methyl-1H-benzotriazole, HG: hexylene glycol, DIW: deionized water

[0198] As shown in Table 2, it was at least confirmed that each example in Table 2 was able to sufficiently remove titanium-based residues and also sufficiently suppress damage to the metal species for which the etching rate was measured.

[0199] 3. Test 3

[0200] 3-1. Preparation of treatment solution

[0201] <Comparative Examples 3-1 to 3-2, 4-1 to 4-2, Examples 3-1 to 3-7, 4-1 to 4-4> Treatment solutions having the compositions shown in Tables 3 and 4 were prepared.

[0202] <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.

[0203] 3-2. Evaluation of titanium residue removal (residue removal)

[0204] 3-2-1. As a first evaluation method, the removability of titanium-based residues was evaluated by the following method.

[0205] A test sample was prepared in the same manner as in "1. Test 1" above, "1-2. Evaluation of removability of titanium-based residue (residue removability)." Etching was then carried out in the same manner as in "1-2. Evaluation of removability of titanium-based residue (residue removability)," to obtain an etched sample (measurement substrate).

[0206] Next, the etched samples (measurement substrates) were cleaned. Cleaning was performed using the following method. First, the treatment solution for each Example and Comparative Example was heated to 58°C. Next, the etched samples were immersed in the treatment solution for each Example and Comparative Example at 58°C (4 minutes of immersion time in the case of Table 3, and 5 minutes of immersion time in the case of Table 4). The samples were then removed from the treatment solution, washed with isopropyl alcohol, and dried by nitrogen blowing. The remaining residue on the samples was then confirmed using a scanning electron microscope (SEM, imaging magnification: 100kx, model name "SU-8220", manufactured by Hitachi High-Technologies Corporation). Specifically, the residue removability was evaluated by confirming whether or not etching residue (titanium-based residue) was present on the hole wall surface. The residue removability was evaluated based on the following criteria.

[0207] The criteria for judging the residue removability are as follows:

[0208] A: The residues confirmed by SEM before immersion were confirmed by SEM after immersion under the same conditions, and more than 95% of them were removed. B: The residue confirmed by SEM before immersion was confirmed by SEM after immersion under the same conditions, and 85% or more but less than 95% was found to have been removed. C: The residue confirmed by SEM before immersion was confirmed by SEM after immersion under the same conditions, and 80% or more but less than 85% was found to have been removed. D: The residues observed by SEM before immersion were examined by SEM under the same conditions after immersion, and it was found that less than 80% of the residues had been removed.

[0209] 3-2-2. As a second evaluation method, the removability of titanium-based residues was also evaluated by the following method (evaluation based on etching rate).

[0210] First, laminates (substrates having films) each including a metal layer were prepared as follows. A laminate was prepared by depositing a metal layer (15 nm thick) of titanium oxide (TiOx) on a substrate (12-inch silicon substrate) using the CVD method. A laminate was prepared by depositing a TiN metal layer (15 nm thick) on a substrate (12-inch silicon substrate) using the CVD method.

[0211] 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 was 30 minutes for TiOx and 15 minutes for TiN. 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.

[0212] The amount of film loss after treatment was evaluated by measuring the etching rate (Å / min). x In the case of the TiN metal layer, it was determined that the higher the etching rate, the greater the residue removal effect.

[0213] 3-3.Evaluation of corrosion resistance

[0214] Test samples were prepared in the same manner as in "1. Test 2" "1-3. Evaluation of corrosion resistance" above, and corrosion resistance was evaluated by measuring the etching rate. In the case of SiN and Al2O3 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.

[0215] The composition of the treatment liquid and the evaluation results of each example are shown in Tables 3 and 4. In the tables, "-" means that the component in question was not added.

[0216] [Table 3]

[0217] [Table 4]

[0218] HF: hydrogen fluoride, 5MBTA: 5-methyl-1H-benzotriazole, HG: hexylene glycol, KOH: potassium hydroxide, KCl: potassium chloride, HCl: hydrogen chloride, MSA: methanesulfonic acid, DIW: deionized water

[0219] From the above, it was confirmed that the treatment solution according to this example can efficiently remove titanium-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.

[0220] This application claims priority to U.S. Provisional Application No. 63 / 557,127, 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]

[0221] 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) an organic solvent; 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) water 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 (C) 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 (C) organic solvent 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 atom selected from the group consisting of silicon atoms, titanium atoms, cobalt 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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