Aqueous composition and cleaning method using the same

Abstract

According to the present invention, there is provided an aqueous composition comprising: 0.0001 to 10% by mass of (A) selected from C 4‑13 Alkylphosphonic acid, C 4‑13 Alkyl phosphonates, C 4‑13 alkylphosphoric acid, and one or more compounds of their salts; and, based on the total amount of the composition, 0.0001 to 50% by mass of (B) excluding C 4‑13 Alkylphosphonic acid, C 4‑13 Alkylphosphonates and C 4‑13 Acids other than alkylphosphoric acids or their salts.

Description

Technical Field

[0001] The present invention relates to an aqueous composition and a cleaning method using the same, and for example, to a cleaning composition used in a manufacturing process of an electronic device (for example, a semiconductor element), and a cleaning method using the same. Background Art

[0002] In the process of manufacturing electronic devices such as semiconductor elements, a dry etching process is usually used to form a semiconductor integrated circuit. In this dry etching process, dry etching residues (zirconium-based residues, titanium-based residues, polymer residues, etc.) are generated and need to be removed. The cleaning agent used to remove the dry etching residue is preferably one that does not cause adverse effects (such as corrosion) on the wiring metal materials (such as copper, titanium, cobalt, tungsten, etc.) used in the semiconductor integrated circuit that is the cleaning object.

[0003] From this point of view, various cleaning agents have been developed. For example, Japanese Patent Publication No. 2013-533631 (Patent Document 1), Japanese Patent Publication No. 2016-171294 (Patent Document 2), Japanese Patent Publication No. 2006-83376 (Patent Document 3), etc. disclose cleaning compositions for removing dry etching residues generated after dry etching, cleaning methods using the same, etc.

[0004] A hard mask is sometimes used in the process of forming a semiconductor integrated circuit. Silicon and titanium based materials have been used as hard mask materials, but in recent years, zirconium oxide based hard masks have also been proposed (Non-Patent Document 1: M Padmanaban et al, J. Photopolym. Sci. Technol., 27 (2014) 503).

[0005] In addition, when forming a via hole by dry etching, a fluorine-based gas is selected. If aluminum oxide is selected as an etching stop layer, aluminum oxide has high resistance to fluorine-based gases, and therefore has the advantage of functioning as an etching stop layer even in a thin film. In recent years, an aluminum oxide-based etching stop layer has been proposed (Non-patent document 2: 16th MME workshop, Goeteborg, Sweden, 2005 "Etch stop materials for release by vapor HF etching").

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application No. 2013-533631

[0009] Patent Document 2: Japanese Patent Application Publication No. 2016-171294

[0010] Patent Document 3: Japanese Patent Application Publication No. 2006-83376

[0011] Non-patent literature

[0012] Non-patent document 1: M Padmanaban et al, J. Photopolym. Sci. Technol., 27 (2014) 503

[0013] Non-patent literature 2: 16th MME workshop, Goeteborg, Sweden, 2005 “Etch stop materials for release by vapor HF etching” Summary of the invention

[0014] Problem that the invention aims to solve

[0015] There are many kinds of metal materials for wiring used in electronic devices and masking materials used in dry etching, and there are also many combinations thereof. Therefore, from the viewpoints of the removal efficiency of dry etching residues and the anticorrosion effect on metal materials for wiring, it is required to develop a new cleaning composition.

[0016] Solutions for solving problems

[0017] The present invention provides the following aqueous composition, a cleaning method using the same, and the like.

[0018] [1] An aqueous composition comprising: 0.0001 to 10% by mass of (A) selected from C 4-13 Alkylphosphonic acid, C 4-13 Alkyl phosphonates, C 4-13 One or more compounds of alkylphosphoric acids and their salts; and

[0019] 0.0001 to 50% by mass of (B) based on the total amount of the composition except C 4-13 Alkylphosphonic acid, C 4-13 Alkylphosphonates and C 4-13 Acids other than alkylphosphoric acids or their salts.

[0020] [2] The composition according to [1] above, wherein the pH thereof is in the range of 0 to 7 (eg, 0 to 6, 0 to 5, 0 to 4, or 0 to 3).

[0021] [3] The composition according to [1] or [2] above, wherein the acid or salt thereof of the component (B) is hydrofluoric acid, nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, or a salt thereof.

[0022] [4] The composition according to [3] above, wherein the acid is hydrofluoric acid.

[0023] [5] The composition according to any one of [1] to [4] above, wherein the aqueous composition contains at least one selected from the following substances:

[0024] As the aforementioned alkylphosphonic acid, n-butylphosphonic acid, n-pentylphosphonic acid, n-hexylphosphonic acid, n-heptylphosphonic acid, n-octylphosphonic acid, n-nonylphosphonic acid, n-decylphosphonic acid, n-undecylphosphonic acid, n-dodecylphosphonic acid, n-tridecylphosphonic acid, or a mixture thereof;

[0025] As the aforementioned alkylphosphonate, n-butylphosphonate, n-pentylphosphonate, n-hexylphosphonate, n-heptylphosphonate, n-octylphosphonate, n-nonylphosphonate, n-decylphosphonate, n-undecylphosphonate, n-dodecylphosphonate, n-tridecylphosphonate, or a mixture thereof; and,

[0026] The aforementioned alkylphosphonic acids and salts of the aforementioned alkylphosphonic acid esters.

[0027] [5a] The composition according to any one of [1] to [5] above, wherein the alkylphosphonic acid is C 5-12 Alkylphosphonic acid (preferably C 5-11 Alkylphosphonic acid, more preferably C 5-9 Alkylphosphonic acid, more preferably C 6-8 Alkylphosphonic acid),

[0028] The aforementioned alkylphosphonic acid esters are esters of these alkylphosphonic acids.

[0029] [6] The composition according to any one of [1] to [4] above, wherein the aqueous composition contains at least one selected from the following substances:

[0030] As the aforementioned alkyl phosphoric acid, n-butyl phosphoric acid, n-pentyl phosphoric acid, n-hexyl phosphoric acid, n-heptyl phosphoric acid, n-octyl phosphoric acid, n-nonyl phosphoric acid, n-decyl phosphoric acid, n-undecyl phosphoric acid, n-dodecyl phosphoric acid, n-tridecyl phosphoric acid, 2-ethylhexyl phosphate, isodecyl phosphate, or a mixture thereof; and

[0031] Salts of the foregoing alkylphosphoric acids.

[0032] [6a] The composition according to any one of [1] to [6] above, wherein the alkylphosphoric acid is C 4-13 Alkyl phosphate (preferably C 5-11 Alkyl phosphate, more preferably C 5-9 Alkyl phosphate, more preferably C 6-8 alkyl phosphate).

[0033] [7] The composition according to any one of [1] to [6] above, wherein the number of alkyl chains in the alkylphosphonic acid, the alkylphosphonic acid ester and the alkylphosphonic acid is 2 or less.

[0034] [8] The composition according to [7] above, wherein the number of alkyl chains in the alkylphosphonic acid, the alkylphosphonic acid ester and the alkylphosphonic acid is 1.

[0035] [9] The composition according to any one of [1] to [8] above, wherein the alkyl chain of the alkylphosphonic acid, the alkylphosphonic acid ester and the alkylphosphonic acid is a linear chain.

[0036]

[10] The composition according to any one of [1] to [9] above, further comprising a barium compound.

[0037]

[11] The composition according to

[10] above, wherein the barium compound includes at least one selected from the group consisting of barium nitrate, barium acetate, barium chloride and barium hydroxide.

[0038] [11a] The composition according to any one of [1] to

[11] above, which is a composition for removing dry etching residue for removing residue after dry etching (for example, zirconium oxide-based dry etching residue).

[0039] [11b] The composition according to any one of [1] to

[11] above, which is a composition for preventing corrosion of wiring materials (such as cobalt or cobalt alloy) of electronic devices to be cleaned.

[0040] [11c] The composition according to any one of [1] to

[11] above, wherein dodecylphosphonic acid is excluded from the alkylphosphonic acid.

[0041]

[12] A method for cleaning an electronic device, comprising the step of bringing the composition according to any one of [1] to

[11] above into contact with the electronic device.

[0042]

[13] A method for producing an electronic device, comprising the step of bringing the composition according to any one of [1] to

[11] above into contact with an electronic device.

[0043]

[14] An etching solution comprising the composition according to any one of [1] to

[11] above.

[0044]

[15] A cleaning solution comprising the composition according to any one of [1] to

[11] above.

[0045] Effects of the Invention

[0046] The aqueous composition according to a preferred embodiment of the present invention exhibits a good anticorrosion effect on cobalt or cobalt alloys even in a low pH region (eg, 4 or less).

[0047] In addition, the aqueous composition described in another preferred embodiment of the present invention (for example, a composition containing hydrogen fluoride) exhibits a good anticorrosion effect on cobalt or cobalt alloys and is also good in the removability of etching residues.

[0048] According to the cleaning method described in the preferred embodiment of the present invention, the anti-corrosion effect on wiring materials such as cobalt and the dry etching residue removal performance are good. Therefore, in the manufacturing process of electronic devices such as semiconductor elements, high-precision and high-quality electronic devices can be manufactured with a good yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 The present invention is a schematic diagram of a cross-sectional view of a semiconductor element in a scheme in which the bottom of a via hole is made of aluminum oxide, and the semiconductor element has a structure including a zirconium oxide-based hard mask 2, cobalt or cobalt alloy 3, aluminum oxide 4, a low dielectric constant interlayer insulating film 5, and silicon nitride 6 before removing dry etching residue 1.

[0050] Figure 2 The present invention is a schematic diagram of a cross-sectional view of a semiconductor element in a scheme in which the bottom of a via hole is cobalt or a cobalt alloy and the semiconductor element has a structure of a zirconium oxide-based hard mask 2, cobalt or a cobalt alloy 3, aluminum oxide 4, a low dielectric constant interlayer insulating film 5, and silicon nitride 6 before removing a dry etching residue 1. DETAILED DESCRIPTION

[0051] The aqueous composition of the present invention comprises: 0.0001 to 10% by mass of (A) selected from C 4-13 Alkylphosphonic acid, C 4-13 Alkyl phosphonates, C 4-13 One or more compounds of alkylphosphoric acids and their salts; and

[0052] 0.0001 to 50% by mass of (B) an acid other than the component (A), that is, other than C 4-13 Alkylphosphonic acid, C 4-13 Alkylphosphonates and C 4-13 Acids other than alkylphosphoric acids, or salts of these acids.

[0053] In addition, in this specification, the range of the content of each component includes an upper limit and a lower limit. For example, the range of the content of the above-mentioned (A) component includes 0.0001 mass % and 10 mass %.

[0054] Hereinafter, the aqueous composition according to the present invention will be described in detail.

[0055] [Component (A): alkylphosphonic acid or alkylphosphonic acid, etc.]

[0056] (A1) Alkylphosphonic acid and alkylphosphonic acid esters

[0057] The alkylphosphonic acid used in the present invention is a C 4-13 Alkylphosphonic acid (alkylphosphonic acid having 4 to 13 carbon atoms). Such alkylphosphonic acid is well known and commercially available (for example, available from Tokyo Chemical Industry Co., Ltd.). The alkylphosphonic acid is preferably C 5-11 Alkylphosphonic acid, more preferably C 5-9 Alkylphosphonic acid, more preferably C 6-8 Alkylphosphonic acid. The alkyl portion of the alkylphosphonic acid may be straight chain or branched, preferably straight chain. When the alkyl portion of the alkylphosphonic acid is branched, the number of branches is preferably 5 or less, more preferably 3 or less, and particularly preferably 1.

[0058] In the aqueous composition of the present invention, the esters of the above-mentioned alkylphosphonic acid may also be used. 4-13 Alkyl esters of alkylphosphonic acid (alkylphosphonic acid having 4 to 13 carbon atoms).

[0059] Alkylphosphonic acids are usually represented by the general formula R 1 P(=O)(OH) 2 (R 1 is an alkyl group), however, the general formula R 1 P(=O)(OR 2 ) 2 (R 1 is an alkyl group, R 2 is an alkyl group or a hydrogen atom: wherein two R 2 The alkyl phosphonates represented by (at least one of the alkyl groups is an alkyl group) can also be used in the aqueous composition.

[0060] In addition, the alkylphosphonic acid esters described in this specification also include alkyl esters of phosphonic acid (phosphonic acid esters). 1 P(=O)(OR 2 ) 2 (R 1 is hydrogen, R 2 is an alkyl group or a hydrogen atom: wherein two R 2 The phosphonate represented by (at least one of the phosphonates is an alkyl group) can also be used in the aqueous composition as an alkyl phosphonate in the present specification.

[0061] As shown above, in the aqueous composition, as the alkylphosphonic acid or the alkylphosphonic acid ester, a compound represented by the following general formula (A) can be used.

[0062] R 1 P(=O)(OR2 ) 2 ···(A)

[0063] (In the general formula (A), R 1 and R 2 Each independently is an alkyl group or a hydrogen atom: wherein R 1 and 2 R 2 At least one of them is an alkyl group.)

[0064] The alkylphosphonate used in the present invention is a C 4-13 Alkylphosphonates (alkylphosphonates having 4 to 13 carbon atoms in total). Alkylphosphonates are preferably C 5-11 Alkyl phosphonate, more preferably C 5-9 Alkylphosphonate, more preferably C 6-8 In addition, R in the above general formula (A) 1 and R 2 The alkyl chains each independently have preferably 4 to 12 carbon atoms, more preferably 6 to 11 carbon atoms, and even more preferably 8 to 10 carbon atoms.

[0065] The alkyl group of the alkylphosphonate, that is, R 1 and R 2 It may be a linear or branched chain, and preferably contains a linear alkyl group.

[0066] In addition, the number of alkyl chains in the above general formula (A), that is, R 1 and R 2 The total number of alkyl chains is preferably 2 or less. That is, as the alkylphosphonate, R of the general formula (A) can also be used. 1 P(=O)(OR 2 ) 2 R 1 and R 2 If all of them are alkyl, R 1 is an alkyl group, R 2 One or less of is alkyl, or R 1 is hydrogen, R 2 More preferably, an alkylphosphonic acid having only a single alkyl chain, that is, R of the general formula (A) is preferably used. 1 P(=O)(OR 2 ) 2 R 1 and 2 R 2 It is particularly preferred that only R in the above general formula (A) is used. 1 An alkyl group.

[0067] The salt of the alkylphosphonic acid used in the present invention is a salt of the above-mentioned alkylphosphonic acid, for example, ammonium salt, tetramethylammonium salt, tetraethylammonium salt, tetrapropylammonium salt, tetrabutylammonium salt, lithium salt, sodium salt, potassium salt, rubidium salt, cesium salt, beryllium salt, magnesium salt, calcium salt, strontium salt, barium salt and the like.

[0068] As the alkylphosphonic acid or its salt used in the present invention, preferably n-butylphosphonic acid, n-pentylphosphonic acid, n-hexylphosphonic acid, n-heptylphosphonic acid, n-octylphosphonic acid, n-nonylphosphonic acid, n-decylphosphonic acid, n-undecylphosphonic acid, n-dodecylphosphonic acid, n-tridecylphosphonic acid, their salts or their mixtures can be mentioned.

[0069] More preferably used alkylphosphonic acid or its salt is n-pentylphosphonic acid, n-hexylphosphonic acid, n-heptylphosphonic acid, n-octylphosphonic acid, n-nonylphosphonic acid, n-decylphosphonic acid, n-undecylphosphonic acid, a salt thereof or a mixture thereof.

[0070] In addition, the salt of the above-mentioned alkylphosphonic acid ester may also be used in the aqueous composition of the present invention. For example, examples of the salt of the alkylphosphonic acid ester include those corresponding to the above-mentioned salt of the alkylphosphonic acid.

[0071] The concentration of alkylphosphonic acid, alkylphosphonic acid ester, or salt thereof in the aqueous composition can be appropriately changed in consideration of the type of wiring material of the electronic device to be etched or cleaned, the type of masking material used in the etching process, etc. The concentration of alkylphosphonic acid, alkylphosphonic acid ester, or salt thereof is preferably 0.0003 to 5% by mass, more preferably 0.0006 to 1% by mass, particularly preferably 0.001 to 0.5% by mass, or 0.01 to 0.1% by mass based on the total amount of the composition.

[0072] (A2) Alkyl phosphate

[0073] The alkylphosphoric acid used in the present invention is a C 4-13 Alkyl phosphoric acid (alkyl phosphoric acid having 4 to 13 carbon atoms). Such alkyl phosphoric acid is well known and commercially available (for example, available from Tokyo Chemical Industry Co., Ltd.). Alkyl phosphoric acid is preferably C 5-11 Alkyl phosphate, more preferably C 5-9 Alkyl phosphate, more preferably C 6-8 Alkyl phosphoric acid. The alkyl portion of the alkyl phosphoric acid may be linear or branched, preferably linear. When the alkyl portion of the alkyl phosphoric acid is branched, the number of branches is preferably 5 or less, more preferably 3 or less, and particularly preferably 1.

[0074] In the aqueous composition of the present invention, as the alkylphosphoric acid, in addition to the monoalkyl ester of phosphoric acid, dialkyl ester and trialkyl ester can also be used. 3 ) 3 (R3 The R of phosphoric acid represented by 3 A monoalkyl ester of phosphoric acid in which only one of the alkyl groups is substituted with an alkyl group, and R 3 A dialkyl ester in which two of the alkyl groups are substituted with alkyl groups, and R 3 All trialkyl esters substituted with alkyl groups can be used in the aqueous composition of the present invention. Among them, as alkyl phosphoric acid, dialkyl esters having 2 or less alkyl chains (the above general formula P(=O)(OR 3 ) 3 R 3 alkyl) and monoalkyl esters (the above general formula P(=O)(OR 3 ) 3 R 3 In other words, the alkylphosphoric acid preferably has a single alkyl chain (as the above R 3 alkyl represented by alkyl).

[0075] The alkylphosphoric acid has a total of 4 to 13 carbon atoms regardless of the number of ester bonds. 5-11 Alkyl phosphonic acid, more preferably C 5-9 Alkyl phosphoric acid, preferably C 6-8 Alkyl phosphate.

[0076] In addition, the above general formula P(=O)(OR 3 ) 3 R 3 The alkyl chain of the alkylphosphonic acid preferably has 4 to 12 carbon atoms, more preferably 6 to 11 carbon atoms, and still more preferably 8 to 10 carbon atoms. 3 ) 3 R 3 It may be a linear or branched chain, and preferably contains a linear alkyl group.

[0077] The salt of the alkyl phosphoric acid used in the present invention is a salt of the monoalkyl ester or dialkyl ester of the above phosphoric acid, for example, ammonium salt, tetramethylammonium salt, tetraethylammonium salt, tetrapropylammonium salt, tetrabutylammonium salt, lithium salt, sodium salt, potassium salt, rubidium salt, cesium salt, beryllium salt, magnesium salt, calcium salt, strontium salt, barium salt and the like.

[0078] As the alkyl phosphoric acid or its salt used in the present invention, preferably n-butyl phosphoric acid, n-pentyl phosphoric acid, n-hexyl phosphoric acid, n-heptyl phosphoric acid, n-octyl phosphoric acid, n-nonyl phosphoric acid, n-decyl phosphoric acid, n-undecyl phosphoric acid, n-dodecyl phosphoric acid, n-tridecyl phosphoric acid, 2-ethylhexyl phosphate, isodecyl phosphate, salts thereof or mixtures thereof can be mentioned.

[0079] More preferably used alkyl phosphoric acid or its salt is n-pentyl phosphoric acid, n-hexyl phosphoric acid, n-heptyl phosphoric acid, n-octyl phosphoric acid, n-nonyl phosphoric acid, n-decyl phosphoric acid, n-undecyl phosphoric acid, 2-ethylhexyl phosphate, isodecyl phosphate, salts thereof or mixtures thereof.

[0080] The concentration of the alkylphosphoric acid or its salt in the aqueous composition can be appropriately changed according to the type of wiring material of the electronic device to be etched or cleaned, the type of masking material used in the etching process, etc. The preferred concentration of the alkylphosphoric acid or its salt is 0.0003 to 5% by mass, more preferably 0.0006 to 1% by mass, particularly preferably 0.001 to 0.5% by mass, or 0.01 to 0.1% by mass based on the total amount of the composition.

[0081] [Component (B): Acid other than component (A)]

[0082] The acid used in the aqueous composition of the present invention may be any inorganic acid or organic acid other than component (A). 4-13 Alkylphosphonic acid, which is a partial ester and also corresponds to the acid C 4-13 Alkyl phosphonates, and C 4-13 Acids other than alkylphosphoric acids. In addition, salts of acids other than the component (A) may be used in the aqueous composition.

[0083] Examples of the inorganic acid that can be used in the present invention include hydrofluoric acid, nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, etc. Among them, hydrofluoric acid is preferred, and when hydrofluoric acid is used, the removability of dry etching residue is improved in a low pH region.

[0084] Examples of the organic acid that can be used in the present invention include aliphatic carboxylic acids having 1 to 18 carbon atoms, aromatic carboxylic acids having 6 to 10 carbon atoms, and amino acids having 1 to 10 carbon atoms.

[0085] Preferred examples of the aliphatic carboxylic acid having 1 to 18 carbon atoms include formic acid, acetic acid, propionic acid, lactic acid, glycolic acid, diglycolic acid, pyruvic acid, malonic acid, butyric acid, hydroxybutyric acid, tartaric acid, succinic acid, malic acid, maleic acid, fumaric acid, valeric acid, glutaric acid, itaconic acid, adipic acid, caproic acid, adipic acid, citric acid, propanetricarboxylic acid, cis-aconitic acid, heptanoic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid.

[0086] Preferred examples of the aromatic carboxylic acid having 6 to 10 carbon atoms include benzoic acid, salicylic acid, mandelic acid, phthalic acid, isophthalic acid, and terephthalic acid.

[0087] Preferred examples of the amino acid having 1 to 10 carbon atoms include carbamic acid, alanine, glycine, asparagine, aspartic acid, sarcosine, serine, glutamine, glutamic acid, 4-aminobutyric acid, iminodibutyric acid, arginine, leucine, isoleucine, and nitrilotriacetic acid.

[0088] The content of the acid in the present composition is 0.0001 to 50% by mass, preferably 0.0005 to 20% by mass, more preferably 0.001 to 10% by mass, further preferably 0.01 to 1% by mass, and particularly preferably 0.02 to 1% by mass.

[0089] [(C) ingredient: water]

[0090] The composition of the present invention is aqueous and contains water as a diluent. The water of the present invention is not particularly limited, but is preferably water from which metal ions, organic impurities, particulate particles, etc. have been removed by distillation, ion exchange treatment, filter treatment, various adsorption treatments, etc., and pure water or ultrapure water is particularly preferred.

[0091] The content of water in the present composition is usually 40 to 99.9998% by mass, preferably 89.5 to 99.998% by mass.

[0092] [Component (D): barium compound]

[0093] The aqueous composition of the present invention may contain a barium compound. The barium compound used in the present invention is an inorganic substance containing barium and has an effect of preventing corrosion of aluminum oxide.

[0094] Examples of the barium compound include barium nitrate, barium acetate, barium chloride, barium hydroxide, barium sulfite, barium chlorate, barium perchlorate, barium peroxide, barium chromate, barium oxide, barium cyanide, barium bromide, barium carbonate, barium metaborate, barium iodide, barium tetrafluoroborate, barium sulfate, barium sulfide, and salts obtained by reacting barium hydroxide with an acid. These may be used alone or in combination of two or more.

[0095] Among them, barium nitrate, barium acetate, barium chloride and barium hydroxide are preferred because they are highly water-soluble and easily available.

[0096] The concentration of the barium compound in the composition is 0.00005 to 10 mass %, preferably 0.00025 to 5 mass %, more preferably 0.001 to 2 mass %, particularly preferably 0.002 to 1 mass %. Within this range, damage to aluminum oxide can be effectively suppressed.

[0097] [Other ingredients]

[0098] The aqueous composition of the present invention may contain additives conventionally used in aqueous compositions for semiconductors as desired within a range that does not impair the purpose of the present invention.

[0099] For example, as additives, bases (such as ammonia), chelating agents, surfactants, defoaming agents, oxidizing agents, reducing agents, metal anticorrosive agents, water-soluble organic solvents, etc. can be added. These additives are well known and described in, for example, JP-2013-533631A.

[0100] [Method for preparing aqueous composition (liquid composition)]

[0101] The aqueous composition (liquid composition) of the present invention can be prepared by adding the above-mentioned component (A), the above-mentioned component (B), water, and, if necessary, the above-mentioned component (D) and the above-mentioned other components, and stirring until the mixture becomes uniform.

[0102] The pH range of the aqueous composition of the present invention is not particularly limited, but is usually 0 to 7, preferably 0 to 6, more preferably 0 to 5, and further preferably 0 to 4.

[0103] According to the aqueous composition of the present invention described in the preferred embodiment, it is possible to prevent the corrosion of cobalt and aluminum oxide, and to efficiently remove dry etching residues.

[0104] [Method of using aqueous composition: Cleaning / manufacturing method of electronic devices]

[0105] The aqueous composition described in the present invention is used as a water-based composition for cleaning (hereinafter also referred to as "cleaning liquid"), and is in contact with an electronic device (such as a semiconductor element) during a wet etching process (or a process before or after it), so that dry etching residues can be removed. As a contact method, for example, the cleaning liquid is contained in a cleaning container, and the electronic device to be cleaned is immersed in the cleaning liquid, so that dry etching residues can be removed and the electronic device is cleaned. Or, the electronic device is treated in a single cleaning method, so that dry etching residues can be removed and the electronic device is cleaned. In addition to being suitable for use as a dry etching residue removing liquid (cleaning liquid), the aqueous composition for cleaning can also be suitable for use as an etching liquid. In addition, the aqueous composition can also be used as a cleaning liquid for cleaning electronic devices after the chemical mechanical polishing (CMP) process.

[0106] Thus, the aqueous composition of the present invention can be suitably used in a cleaning method including a step of cleaning an electronic device, and a method for producing an electronic device including such a step.

[0107] The temperature at which the cleaning solution of the present invention is used is usually 10 to 80° C., preferably 15 to 70° C., more preferably 20 to 65° C., particularly preferably 20 to 60° C. The temperature can be appropriately selected depending on the cleaning conditions and the electronic device (eg, semiconductor element) used.

[0108] The cleaning solution of the present invention is usually used for 0.2 to 60 minutes. The time can be appropriately selected according to the cleaning conditions and the electronic device (e.g., semiconductor element) used. As the rinse solution after using the cleaning solution of the present invention, organic solvents, water, carbonated water, and ammonia water can be used.

[0109] [Electronic components to be cleaned / manufactured]

[0110] The cleaning objects and electronic devices that can be suitably used in the present invention are, for example, semiconductor elements and display elements. Usually, the intermediate products after the dry etching process become the objects of cleaning. Semiconductor elements and display elements are substrate materials such as silicon, amorphous silicon, polycrystalline silicon, glass, insulating materials such as silicon oxide, silicon nitride, silicon carbide and their derivatives, materials such as cobalt, cobalt alloys, tungsten, titanium-tungsten, compound semiconductors such as gallium-arsenic, gallium-phosphorus, indium-phosphorus, indium-gallium-arsenic, indium-aluminum-arsenic, and oxide semiconductors such as chromium oxide. As electronic devices that become the cleaning objects of the present invention, particularly preferably, there can be cited elements using cobalt or cobalt alloy wiring materials, zirconium oxide-based hard masks, and low dielectric constant interlayer insulating films.

[0111] The dry etching residues that are the target of the present invention are generated when, for example, a via hole or a trench is formed in a low dielectric constant interlayer insulating film by dry etching using a zirconium oxide hard mask as a mask. A portion of the dry etching residues is generated when the etching gas contacts the zirconium oxide hard mask. Therefore, in this case, the target dry etching residues contain zirconium.

[0112] Example

[0113] Hereinafter, the present invention will be specifically described based on examples, but the embodiments may be modified as appropriate as long as the effects of the present invention are exhibited.

[0114] It should be noted that, unless otherwise specified, % means mass %.

[0115] [Evaluation wafer]

[0116] <Evaluation Wafer A>: Evaluation of the removal status of dry etching residue

[0117] Silicon nitride, an interlayer insulating film, silicon nitride, zirconium oxide, and a photoresist are formed from the bottom layer, and then the photoresist is patterned.

[0118] Using the photoresist as a mask, predetermined portions of the hard mask are removed by dry etching, and the photoresist is removed by ashing using oxygen plasma. Furthermore, using the hard mask as a mask, via holes are formed in the silicon nitride and interlayer insulating film by dry etching.

[0119] <Wafer with film>:For damage evaluation of cobalt and aluminum oxide

[0120] Wafers with films formed of cobalt and aluminum oxide were produced under the following film forming conditions.

[0121] (1) Cobalt; film is prepared by physical vapor deposition method, A film of thickness is formed on Si.

[0122] (2) Aluminum oxide; film formed by physical vapor deposition, A film of thickness is formed on Si.

[0123] [Evaluation method]

[0124] <Dry etching residue removal status>

[0125] SEM observation was performed on the evaluation wafer A after being treated with various aqueous compositions (cleaning solutions).

[0126] Measurement equipment: Hitachi High-Technologies Corporation, ultra-high resolution field emission scanning electron microscope SU9000 (magnification 100,000 times)

[0127] Determination method:

[0128] E: Dry etching residue is completely removed.

[0129] G: The dry etching residue is almost completely removed.

[0130] P: Removal of dry etching residue is insufficient.

[0131] E and G were judged as passing.

[0132] <Film thickness>

[0133] The film thickness of the wafer with film was measured using a fluorescent X-ray device SEA1200VX (film thickness measuring device A) manufactured by SII NanoTechnology Inc. or an optical film thickness meter N&K1280 (film thickness measuring device B) manufactured by N&K Technology Company. The film thickness of the wafer with cobalt film was measured using the film thickness measuring device A, and the film thickness of the wafer with aluminum oxide film was measured using the film thickness measuring device B.

[0134] <ER(etching rate)>

[0135] Each wafer with a film is treated with a cleaning solution, and the difference in film thickness before and after the treatment is divided by the treatment time to calculate the ER.

[0136] In the case of cobalt, the ER is / minute or less is considered a good product. In the case of aluminum oxide, ER is / min or less is considered a good product.

[0137] <Measurement of pH value>

[0138] The pH value of the aqueous composition of each Example and Reference Example was measured at 25° C. using a pH meter (pH meter F-52 manufactured by Horiba, Ltd.).

[0139] [Examples 1 to 31]

[0140] Evaluation wafer A and wafers with various films were used in the test. The wafers were immersed in the cleaning solutions listed in Tables 1 and 2 at the processing temperatures listed in Tables 1 and 2, and then rinsed with ultrapure water and dried by spraying dry nitrogen gas. Evaluation wafer A was treated for 5 minutes, and the treated wafer was observed using a SEM.

[0141] For each wafer with a film, the cobalt film was treated for 30 minutes, and the aluminum oxide film was treated for 5 minutes. The ER was calculated from the film thickness before and after the treatment.

[0142] [Examples 1 to 31 and Reference Examples 1 to 23]

[0143] Evaluation wafer A, wafers with cobalt films, and wafers with aluminum oxide films were used in the test. They were immersed in the aqueous composition (cleaning solution) described in Table 1, Table 2, and Table 3 at 20°C or 50°C (refer to the item of treatment temperature in the table), and then rinsed with ultrapure water and dried by spraying dry nitrogen gas. For evaluation wafer A, all were immersed for 5 minutes, and the treated wafers were observed with SEM.

[0144] The wafer with the cobalt film was immersed for 30 minutes, and the wafer with the aluminum oxide film was immersed for 5 minutes, and the ER was calculated from the film thickness before and after the treatment.

[0145] It is understood that in Examples 1 to 31, damage to cobalt was prevented.

[0146] On the other hand, it can be seen that the reference examples in Table 3 are not sufficiently suitable for the purpose of suppressing damage to cobalt.

[0147] In addition, it was found that the HF-containing compositions in Tables 1 and 2 were able to remove the dry etching residue contained in the evaluation wafer A.

[0148] It can be further seen that in the examples of Table 2, the composition containing the barium compound prevents the damage of aluminum oxide.

[0149] [Table 1]

[0150]

[0151] [Table 2]

[0152]

[0153] [Table 3]

[0154]

[0155] Industrial Applicability

[0156] The aqueous composition according to a preferred embodiment of the present invention exhibits a good anticorrosion effect on cobalt or cobalt alloys even in a low pH region (eg, 4 or less).

[0157] In addition, the aqueous composition described in another preferred embodiment of the present invention (for example, a composition containing hydrogen fluoride) exhibits a good anticorrosion effect on cobalt or cobalt alloys and is also good in the removability of dry etching residues.

[0158] Moreover, the etching solution, cleaning solution and cleaning method described in the preferred embodiment of the present invention have good anti-corrosion effect on wiring materials such as cobalt and dry etching residue removal properties. Therefore, in the manufacturing process of electronic devices such as semiconductor elements, high-precision and high-quality electronic devices can be manufactured with a good yield.

[0159] Description of Reference Numerals

[0160] 1. Zirconia-based dry etching residue

[0161] 2. Zirconia hard mask

[0162] 3. Cobalt or cobalt alloy

[0163] 4. Alumina

[0164] 5. Low dielectric constant interlayer insulation film

[0165] 6. Silicon Nitride (SiN)

Claims

1. An aqueous composition comprising: 0.0001 to 10% by mass of (A) based on the total amount of the composition is selected from C 5-11 Alkylphosphonic acid, C 5-11 Alkyl phosphonates, C 4-13 One or more compounds of alkylphosphoric acids and their salts; and 0.0001 to 50% by mass of (B) based on the total amount of the composition except C 5-11 Alkylphosphonic acid, C 5-11 Alkylphosphonates and C 4-13 Acids other than alkylphosphonic acids or their salts, The pH of the aqueous composition is in the range of 0-7.

2. The composition according to claim 1, wherein The acid or salt thereof of the component (B) is hydrofluoric acid, nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, or salts thereof.

3. The composition according to claim 2, wherein The acid is hydrofluoric acid.

4. The composition according to claim 1 or 2, wherein The aqueous composition comprises at least any one selected from the following substances: As the alkylphosphonic acid, n-pentylphosphonic acid, n-hexylphosphonic acid, n-heptylphosphonic acid, n-octylphosphonic acid, n-nonylphosphonic acid, n-decylphosphonic acid, n-undecylphosphonic acid, or a mixture thereof; As the alkylphosphonate, n-pentylphosphonate, n-hexylphosphonate, n-heptylphosphonate, n-octylphosphonate, n-nonylphosphonate, n-decylphosphonate, n-undecylphosphonate, or a mixture thereof; and, The alkylphosphonic acids and the salts of the alkylphosphonic acid esters.

5. The composition according to claim 1 or 2, wherein The aqueous composition comprises at least any one selected from the following substances: As the alkyl phosphoric acid, n-butyl phosphoric acid, n-pentyl phosphoric acid, n-hexyl phosphoric acid, n-heptyl phosphoric acid, n-octyl phosphoric acid, n-nonyl phosphoric acid, n-decyl phosphoric acid, n-undecyl phosphoric acid, n-dodecyl phosphoric acid, n-tridecyl phosphoric acid, 2-ethylhexyl phosphate, isodecyl phosphate, or a mixture thereof; and A salt of said alkylphosphoric acid.

6. The composition according to claim 1 or 2, wherein In the alkylphosphonic acid, the alkylphosphonic acid ester and the alkylphosphonic acid, the number of alkyl chains is 2 or less.

7. The composition according to claim 6, wherein In the alkylphosphonic acid, the alkylphosphonic acid ester and the alkylphosphonic acid, the number of alkyl chains is 1.

8. The composition according to claim 1 or 2, wherein In the alkylphosphonic acid, the alkylphosphonic acid ester and the alkylphosphonic acid, the alkyl chain is a straight chain.

9. The composition according to claim 1 or 2, wherein Also includes barium compounds.

10. The composition according to claim 9, wherein The barium compound includes at least any one selected from barium nitrate, barium acetate, barium chloride, and barium hydroxide. 11 . A method for cleaning an electronic device, comprising the step of bringing the composition according to claim 1 into contact with an electronic device. 12 . A method for producing an electronic device, comprising the step of bringing the composition according to claim 1 into contact with an electronic device. 13 . An etching solution comprising the composition according to claim 1 .

14. A cleaning solution comprising the composition according to any one of claims 1 to 10.

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