KR20230037604A - Metal complex, composition, resist material, pattern formation method, and electronic device manufacturing method - Google Patents

Abstract

A resist material usable for radiation lithography that is highly sensitive and capable of forming fine patterns is provided. Specifically, a metal complex characterized by having an anionic compound (A) represented by the following general formula (1) as a ligand (R ¹ and R ² are an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group , Represents an aralkyl group or halogen atom m, n and p represent an integer of 0 to 4. R ³ is a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or an alkoxy group on a hydrocarbon group, or a halogen group and a structural part having at least one substituent selected from hydroxyl groups, R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom.)

Description

Metal complex, composition, resist material, pattern formation method, and electronic device manufacturing method

The present invention relates to a metal complex, a composition, a resist material, a pattern formation method, and an electronic device manufacturing method.

In the field of manufacturing semiconductors such as ICs and LSIs, development of lithography techniques using radiation such as electron beams (EB) and extreme ultraviolet (EUV) is progressing because finer patterns can be formed. In the lithography technology using these radiations, there is a problem that development and light source intensity are low, and development of a more highly sensitive lithography resist material is demanded. As one of the techniques for increasing the sensitivity of a lithography resist material, for example, a technique using metal oxide nanoparticles has been studied (see Patent Document 1). In this technology, when metal oxide nanoparticles having a particle size of 20 nm or less absorb the radiation, secondary electrons are generated from polymers in the resist composition, which promote decomposition of the photoacid generator, so a more highly sensitive positive type photoresist function as However, metal oxide nanoparticles are prone to aggregation, and stability as an industrial material is insufficient, and there are problems that radiation absorption efficiency gradually decreases with aggregation of metal oxide nanoparticles.

As another technique, for example, a technique using a metal complex is being studied (see Patent Literature 2). In this technology, a metal oxide is generated from a metal complex of β diketones by irradiation with radiation, and since this is insoluble in an alkaline developer, it functions as a negative photoresist. However, in practice, the efficiency of generating metal oxides by irradiation with radiation is not sufficient, and sensitivity that can meet the market demand has not been realized. In addition, in practical use, the addition of a relatively high molecular weight polymer is required, so it is not suitable for production of ultrafine patterns with a width of nm.

In this way, in the lithography technique using radiation, there has been a demand for the development of a resist material that is highly sensitive and capable of forming fine patterns.

International Publication No. 2016/088655 Japanese Patent Laid-Open No. 2012-185485

An object to be solved by the present invention is to provide a resist material usable for radiation lithography that is highly sensitive and can form fine patterns.

As a result of intensive studies to solve the above problems, the inventors of the present invention have found that, by using a metal complex having an anionic compound having a specific structure as a ligand, it is highly sensitive and can be used for radiation lithography capable of forming fine patterns. The present invention was completed by discovering that a resist material is feasible.

That is, the present invention relates to a metal complex characterized by having an anionic compound (A) represented by the following general formula (1) as a ligand.

[In Formula (1), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. m, n and p represent the integer of 0-4 each independently. When a plurality of R ^{1 '} s are present, the plurality of R ¹ 's may be the same as or different from each other. When R ² is plural, plural R ² may be the same as or different from each other. R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on the hydrocarbon group. R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. When R ⁴ is plural, plural R ⁴ may be the same or different.]

Further, the present invention relates to a composition characterized by containing a compound (a) represented by the following general formula (2) and a metal complex (b).

[In Formula (2), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. m, n and p represent the integer of 0-4 each independently. When a plurality of R ^{1 '} s are present, the plurality of R ¹ 's may be the same as or different from each other. When R ² is plural, plural R ² may be the same as or different from each other. R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on the hydrocarbon group. R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. When R ⁴ is plural, plural R ⁴ may be the same or different.]

Further, the present invention relates to a resist material using the metal complex or composition.

Further, the present invention relates to a method of forming a pattern using the resist material and a method of manufacturing an electronic device including the method of forming the pattern.

According to the present invention, it is possible to provide a resist material that is highly sensitive and can be used for radiation lithography capable of forming fine patterns.

1 is a GPC chart of compound (a) obtained in Synthesis Example 1;
2 is a ¹³ C-NMR chart of compound (a) obtained in Synthesis Example 1;
3 is an FT-IR spectrum of a metal complex (1) solution obtained in Example 1;

Hereinafter, one embodiment of the present invention will be described. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within a range not impairing the effects of the present invention.

The metal complex of the present invention is characterized by having an anionic compound (A) represented by the following general formula (1) as a ligand.

[In Formula (1), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. m, n and p represent the integer of 0-4 each independently. When a plurality of R ^{1 '} s are present, the plurality of R ¹ 's may be the same as or different from each other. When R ² is plural, plural R ² may be the same as or different from each other. R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on the hydrocarbon group. R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. When R ⁴ is plural, plural R ⁴ may be the same or different.]

In the above general formula (1), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. The aliphatic hydrocarbon group may be straight-chain or may have a branched structure. Moreover, you may have a cyclocyclic structure. More specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a t-butyl group, a hexyl group, a cyclohexyl group, a heptyl group, an octyl group, a nonyl group, etc. are mentioned. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, a butoxy group, a pentyloxy group, a hexyloxy group, and a cyclohexyloxy group. Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and an anthryl group. Examples of the aralkyl group include a benzyl group, a phenylethyl group, a phenylpropyl group, and a naphthylmethyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Among them, R ¹ and R ² are preferably alkyl groups of 1 to 4 carbon atoms, particularly preferably methyl groups, since they are excellent in the ability to form fine patterns when used as a resist material. Further, m and n in Structural Formula (1) are integers of 0 to 4, but are more preferably integers of 1 to 3, and particularly preferably 2. At this time, it is preferable that two R ¹ and two R ² are each bonded to the 2,5-position of the phenolic hydroxyl group.

In Formula (1), R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group, and a hydroxyl group on the hydrocarbon group. Examples of the aliphatic hydrocarbon group having 1 to 9 carbon atoms include those exemplified as R ¹ and R ² above. In addition, as "a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on a hydrocarbon group", halogenated alkyl groups, halogenated aryl groups, 2-methoxyethoxy groups, 2-ethoxyethoxy groups, etc. and an alkoxyalkoxy group, an alkylalkoxy group substituted with a hydroxyl group, and the like. Among them, it is preferable that R ³ is a hydrogen atom.

In the general formula (1), R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. Specific examples of each include those exemplified as R ¹ and R ² above. Also, p represents an integer of 0 to 4. Among them, it is preferable that p is 0.

In the present invention, as the anionic compound (A), one having the same structure may be used alone, or a plurality of compounds having mutually different molecular structures may be used.

In the metal complex of the present invention, the type of central metal is not particularly limited, and a wide variety of materials can be used. Moreover, as a metal complex, the thing with the same center metal may be used independently, and multiple types of things with a different center metal may be used. Specific examples of the central metal include magnesium, aluminum, calcium, titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, silver, cadmium, indium, tin, antimony, cesium, hafnium and the like. Among them, one of zirconium, tin, and hafnium is preferable. In addition, the valence of the central metal is not particularly limited, and any valence complex may be used.

The metal complex of the present invention may have other ligands other than the above anion compound (A). Specific examples of other ligands include RO ^- (R is a hydrocarbon group having 1 to 10 carbon atoms), RCOO ^- (R is a hydrocarbon group having 1 to 10 carbon atoms), [R ¹ COCH ₂ COR ² ] ^- (R ¹ and R ² is each independently a hydrocarbon group having 1 to 10 carbon atoms), amine-based ligands, imine-based ligands, phosphine-based ligands, alkyl-based ligands, alkene-based ligands, alkyne-based ligands, aryl-based ligands, and the like. Among them, RO ^- (R is a hydrocarbon group having 1 to 22 carbon atoms) is preferable, and it is preferable that R is a hydrocarbon group having 2 to 6 carbon atoms, as it has excellent photosensitivity and alkali solubility when used as a resist material.

When the metal complex of the present invention has ligands other than the anion compound (A), the ratio of the anion compound (A) and the ligand different from each other is such that the effect of the present invention is sufficiently exhibited, and both The ratio of the anionic compound (A) to the total is preferably 20 mol% or more, more preferably 50 mol% or more, and particularly preferably 80 mol% or more. In addition, the said ratio is an average value of the value in each molecule.

The method for producing the metal complex of the present invention is not particularly limited, and may be produced by any method. As an example, it can be manufactured by mixing a compound (a) represented by the following general formula (2) and a metal complex (b) as a raw material in a solvent, for example.

[In Formula (2), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. m, n and p represent the integer of 0-4 each independently. When a plurality of R ^{1 '} s are present, the plurality of R ¹ 's may be the same as or different from each other. When R ² is plural, plural R ² may be the same as or different from each other. R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on the hydrocarbon group. R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. When R ⁴ is plural, plural R ⁴ may be the same or different.]

Each symbol in the said general formula (2) is synonymous with the thing in the said structural formula (1), and the preferable form is also the same as that of the said general formula (1). The compound (a) may be used singly, or may be used in combination with a plurality of compounds having different structures.

The compound (a) may be produced by any method, but as an example, for example, a phenolic compound (a1) and formylbenzoic acids (a2) are mixed in the presence of an acid catalyst, using a solvent as necessary, It can be obtained by heating and polycondensation in the range of ~ 140 ° C.

The phenol compound (a1) is a compound having one or more substituents such as an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group or a halogen atom on the aromatic ring of the phenol, in addition to phenol. can be heard Specific examples of these substituents include those exemplified as R ¹ and R ² in the structural formulas (1) and (2) above. Among them, those having 1 to 3 alkyl groups of 1 to 4 carbon atoms are preferable, and those having 2 are particularly preferable, as they are excellent in the ability to form fine patterns when used as a resist material. At this time, it is preferable that the two alkyl groups are bonded to the 2,5-position of the phenolic hydroxyl group, respectively. Moreover, as an alkyl group, a methyl group is especially preferable.

The formylbenzoic acid (a2) is, for example, formylbenzoic acid, a compound having one to more hydroxyl groups, aliphatic hydrocarbon groups having 1 to 9 carbon atoms, alkoxy groups or halogen atoms on its aromatic ring, acetyl Aromatic ketones having a carboxy group such as benzoic acid, and compounds having one or more hydroxyl groups, aliphatic hydrocarbon groups of 1 to 9 carbon atoms, alkoxy groups, or halogen atoms on their aromatic rings. Specific examples of the C1-C9 aliphatic hydrocarbon group, alkoxy group, or halogen atom include those exemplified as R ⁴ in Structural Formulas (1) and (2). Among them, formylbenzoic acid is preferable because of its excellent reactivity with the phenolic compound (a1), and 4-formylbenzoic acid is more preferable since it provides a molecular structure that is easily coordinated on a metal atom.

As for the acid catalyst used for manufacture of the said compound (a), acetic acid, oxalic acid, sulfuric acid, hydrochloric acid, phenolsulfonic acid, p-toluenesulfonic acid, zinc acetate, manganese acetate etc. are mentioned, for example. These acid catalysts may be used alone or in combination of two or more. Among these acid catalysts, sulfuric acid and p-toluenesulfonic acid are preferable from the viewpoint of excellent activity. In addition, the acid catalyst may be added before or during the reaction.

When a solvent is used for the preparation of the compound (a), specific examples thereof include carboxylic acid compounds such as formic acid, acetic acid, propionic acid, butyric acid, and valeric acid; Glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl methyl ether, and ethylene glycol monophenyl ether compound; cyclic ether compounds such as 1,3-dioxane and 1,4-dioxane; glycol ester compounds such as ethylene glycol acetate; ketone compounds such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; Aromatic hydrocarbons, such as toluene and xylene, etc. are mentioned. These solvents may be used alone or in combination of two or more. Moreover, among these solvents, acetic acid is preferable from the point of being excellent in the solubility of the obtained compound.

The input ratio [(a1)/(a2)] of the phenolic compound (a1) and the formylbenzoic acids (a2) determines the removability of the unreacted phenolic compound (a1), the yield of the obtained compound (a), and It is excellent in purity, and the range of 1/0.8 to 1/0.2 in molar ratio is preferable, and the range of 1/0.6 to 1/0.4 is more preferable.

After completion of the reaction, for example, the reaction product is poured into a poor solvent (S1) in which the reaction product is insoluble or sparingly soluble, and the resulting precipitate is separated by filtration to obtain a crude product. The compound ( a) can be purified and isolated. In the case where an aromatic hydrocarbon such as toluene or xylene is used as the reaction solvent, the compound (a) as a product is dissolved in the solvent by heating at 80° C. or higher, and thus crystals of the compound (a) precipitate by cooling as it is. And, the compound (a) can be isolated by filtration. In this case, it is not necessary to use the poor solvent (S1) and the solvent (S2).

Examples of the poor solvent (S1) include water; Monoalcohols, such as methanol, ethanol, and a propanol; aliphatic hydrocarbons such as n-hexane, n-heptane, n-octane, and cyclohexane; Aromatic hydrocarbons, such as toluene and xylene, are mentioned. Among these poor solvents (S1), water and methanol are preferable because they can efficiently remove the acid catalyst at the same time.

Examples of the solvent (S2) include monoalcohols such as methanol, ethanol, and propanol; Ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol polyols such as 1,9-nonanediol, trimethylene glycol, diethylene glycol, polyethylene glycol, and glycerin; 2-ethoxyethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol dimethyl ether, ethylene glycol ethylmethyl ether, ethylene glycol mono glycol ethers such as phenyl ether; cyclic ethers such as 1,3-dioxane and 1,4-dioxane; glycol esters such as ethylene glycol acetate; Ketones, such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, etc. are mentioned. In addition, when water is used as the poor solvent (S1), acetone is preferable as the (S2). In addition, as for the poor solvent (S1) and the solvent (S2), only one type may be used, or two or more types may be used together.

The purity of the compound (a) is preferably 90% or more, more preferably 94% or more, and particularly preferably 98% or more, as a value calculated from a gel permeation chromatography (GPC) chart. In addition, the measurement conditions of GPC are those described in the Example.

The metal complex (b) is not particularly limited as long as ligand exchange occurs by mixing with the compound (a) and the metal complex of the present invention can be formed, and various types of materials can be used. In addition, the said metal complex (b) may be used individually by 1 type, and may use two or more types together. As the central metal of the metal complex (b), as in the metal complex of the present invention, magnesium, aluminum, calcium, titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, silver, cadmium, indium, tin , antimony, cesium, hafnium and the like. Among them, one of zirconium, tin, and hafnium is preferable. In addition, the valence of the central metal is not particularly limited, and any valence complex may be used.

The ligand of the metal complex (b) is, for example, RO ^- (R is a hydrocarbon group having 1 to 10 carbon atoms), RCOO ^- (R is a hydrocarbon group having 1 to 10 carbon atoms), [R ¹ COCH ₂ COR ² ] ^- (R ¹ and R ² are each independently a hydrocarbon group having 1 to 10 carbon atoms), [R ¹ COCH ₂ COOR ² ] ^- (R ¹ and R ² are each independently a hydrocarbon group having 1 to 10 carbon atoms) group), amine-based ligands, imine-based ligands, phosphine-based ligands, alkyl-based ligands, alkene-based ligands, alkyne-based ligands, aryl-based ligands and the like. Among them, RO ^- (R is a hydrocarbon group having 1 to 22 carbon atoms) is preferable because the resulting metal complex has excellent photosensitivity and alkali solubility when used as a resist material, and R is a hydrocarbon group having 2 to 6 carbon atoms. it is desirable

The mixing ratio of the compound (a) and the metal complex (b) is such that the effect of the present invention is sufficiently exhibited, and the compound (a) is 0.5 to 10 per mole of the central metal of the metal complex (b). It is preferable that it is a ratio used in the range of moles, and it is more preferable that it is a ratio used in the range of 2 to 6 moles.

The solvent is not particularly limited as long as it can dissolve the compound (a) and the metal complex (b), and a wide variety of solvents can be used. Specific examples include monoalcohols such as methanol, ethanol, propanol, and butanol; Ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol polyols such as 1,9-nonanediol, trimethylene glycol, diethylene glycol, polyethylene glycol, and glycerin; 2-ethoxyethanol, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl Glycol ethers such as methyl ether, ethylene glycol monophenyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, and diethylene glycol dibutyl ether, methyl cellosolve acetate, ethyl cellosolve ethylene glycol alkyl ether acetates such as acetate; propylene glycol ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monopropyl ether acetate; cyclic ethers such as tetrahydrofuran, 1,3-dioxane, and 1,4-dioxane; glycol esters such as ethylene glycol acetate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; 2-Hydroxymethylpropionate, 2-hydroxyethylpropionate, 2-hydroxy-2-methylethylpropionate, ethoxyethyl acetate, oxyacetate ethyl, 2-hydroxy-3-methylbutanoic acid methyl, 3-methoxy Ester compounds such as butyl acetate, 3-methyl-3-methoxybutyl acetate, ethyl formate, ethyl acetate, butyl acetate, methyl acetoacetate, ethyl acetoacetate: acetonitrile, acrylonitrile, propionitrile, butyronitrile, etc. Nitrile compounds of , etc. are mentioned. These solvents may be used individually by one type, or may be used as a mixed solvent of two or more types.

Although the amount of the solvent used is not particularly limited, it is preferably in the range of 1 to 500 parts by mass relative to 1 part by mass of the raw material component of the metal complex.

The temperature conditions at the time of mixing the raw materials of the metal complex are not particularly limited, and may be room temperature of about 20 to 25° C., or may be heated appropriately as necessary.

Generation of the metal complex can be confirmed from, for example, a peak at 1400 cm ⁻¹ in the IR spectrum.

For the resist material containing the metal complex of the present invention, a metal complex prepared in advance may be used, and compound (a) and metal complex (b), which are raw materials for the metal complex, are separately blended to form a metal complex in the resist material. may generate

The resist material of the present invention may contain a solvent. As a solvent type, what was used when mixing the said compound (a) and the said metal complex (b), etc. are mentioned. The amount of the solvent used is not particularly limited, and is appropriately adjusted depending on the specific application and the like. In particular, it is preferable that the solid content concentration in the resist material is in the range of 0.1 to 50% by mass in order to obtain a uniform film thickness upon application by spin coating or the like.

In the resist material of the present invention, since the anionic compound (A), which is the ligand of the metal complex, has sufficient film forming properties, the metal complex itself can be used as a resist material without using other resin components. You may use resin. Examples of alkali-soluble resins include various novolac-type phenolic resins. When an alkali-soluble resin is used, the effect of the present invention is sufficiently exhibited, and the ratio of the metal complex to the total mass of the metal complex and the alkali-soluble resin is preferably 50% by mass or more, and more preferably 75% by mass or more. And it is particularly preferable that it is 90 mass % or more.

The resist material of the present invention may contain other components as needed. Specific examples of other components include, for example, surfactants such as curing agents, photoacid generators, photosensitizers, fillers, pigments, and leveling agents, adhesion improvers, dissolution promoters, and the like. When these other components are used, the effects of the present invention can be fully exhibited, so that the ratio of the metal complex to the total mass of components other than the solvent in the resist material is preferably 50% by mass or more, and more preferably 75% by mass or more. It is preferable, and it is especially preferable that it is 90 mass % or more.

The curing agent is, for example, a melamine compound, a guanamine compound, a glycoluril compound, a urea compound, a resol resin, an epoxy compound, an isocyanate compound, an azide compound, a compound containing a double bond such as an alkenyl ether group, an acid Anhydride, oxazoline compound, etc. are mentioned.

Examples of the melamine compound include hexamethylolmelamine, hexamethoxymethylmelamine, a compound in which 1 to 6 methylol groups of hexamethylolmelamine are methoxymethylated, hexamethoxyethylmelamine, hexaacyloxymethylmelamine, Compounds in which 1 to 6 of the methylol groups of hexamethylolmelamine were acyloxymethylated, and the like are exemplified.

Examples of the guanamine compound include compounds obtained by methoxymethylation of 1 to 4 methylol groups of tetramethylolguanamine, tetramethoxymethylguanamine, tetramethoxymethylbenzoguanamine, and tetramethylolguanamine; The compound etc. which 1-4 methylol groups of tetramethoxyethyl guanamine, tetraacyloxy guanamine, and tetramethylol guanamine were acyloxymethylated are mentioned.

Examples of the glycoluril compound include 1,3,4,6-tetrakis(methoxymethyl)glycoluril, 1,3,4,6-tetrakis(butoxymethyl)glycoluril, 1,3, 4, 6- tetrakis (hydroxymethyl) glycoluril etc. are mentioned.

Examples of the urea compound include 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetrakis(butoxymethyl)urea and 1,1,3,3-tetrakis(methyl)urea. toxymethyl) urea; and the like.

Examples of the resol resin include alkylphenols such as phenol, cresol and xylenol, phenylphenol, resorcinol, biphenyl, bisphenol such as bisphenol A and bisphenol F, naphthol, and phenolic such as dihydroxynaphthalene. and polymers obtained by reacting a hydroxyl group-containing compound with an aldehyde compound under alkaline catalytic conditions.

Examples of the epoxy compound include diglycidyloxynaphthalene, phenol novolak type epoxy resin, cresol novolak type epoxy resin, naphthol novolak type epoxy resin, naphthol-phenol coaxial novolac type epoxy resin, and naphthol-cresol. Coaxial novolac type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, 1,1-bis(2,7-diglycidyloxy-1-naphthyl)alkane, naphthylene ether type epoxy resin, tree Phenylmethane-type epoxy resins, dicyclopentadiene-phenol addition reaction type epoxy resins, phosphorus atom-containing epoxy resins, and polyglycidyl ethers of cocondensates of phenolic hydroxyl group-containing compounds and alkoxy group-containing aromatic compounds.

As said isocyanate compound, tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate etc. are mentioned, for example.

Examples of the azide compound include 1,1'-biphenyl-4,4'-bisazide, 4,4'-methylidenebisazide, and 4,4'-oxybisazide. can

Examples of the compound containing a double bond such as the alkenyl ether group include ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, and 1,4-butanediol divinyl Ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylolpropane trivinyl ether, hexanediol divinyl ether, 1,4-cyclohexanediol divinyl ether, 1,4-cyclohexanedimethanol divinyl Ether, pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, trimethylolpropane trivinyl ether, etc. are mentioned.

Examples of the acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, and 4,4'. aromatic acid anhydrides such as -(isopropylidene)diphthalic anhydride and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride; and alicyclic carboxylic acid anhydrides such as tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, decenylsuccinic anhydride, and trialkyltetrahydrophthalic anhydride. . The said hardening|curing agent may be used individually by 1 type, and may use 2 or more types together.

The content of the curing agent in the resist material is preferably in the range of 5 to 50% by mass based on the solid content of the resist material. The solid content of the resist material refers to the total of components other than the solvent in the resist material.

Examples of the photoacid generator include onium salt compounds, sulfonimide compounds, halogen-containing compounds, and diazoketone compounds. Among these, onium salt compounds are preferred.

As said onium salt compound, a sulfonium salt, a tetrahydrothiophenium salt, an iodonium salt, a phosphonium salt, a diazonium salt, a pyridinium salt etc. are mentioned, for example.

As said sulfonium salt, for example, triphenyl sulfonium trifluoromethane sulfonate, triphenyl sulfonium nonafluoro-n-butane sulfonate, triphenyl sulfonium perfluoro-n-octane sulfonate, triphenyl sulfonate Phonium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2,2-tetrafluoroethanesulfonate, triphenylsulfonium camphorsulfonate, 4-cyclohexylphenyldiphenylsulfonium trifluoro Romethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexylphenyldiphenylsulfonium perfluoro-n-octanesulfonate, 4-cyclohexylphenyldiphenyl Sulfonium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-cyclohexylphenyldiphenylsulfoniumcamphorsulfonate, 4-methanesulfonyl Phenyldiphenylsulfonium trifluoromethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-methanesulfonylphenyldiphenylsulfoniumperfluoro-n-octanesulfonate nate, 4-methanesulfonylphenyldiphenylsulfonium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-methanesulfonylphenyldiphenyl Sulfonium camphorsulfonate, triphenylsulfonium 2-(1-adamantyl)-1,1-difluoroethanesulfonate, triphenylsulfonium 6-(1-adamantylcarbonyloxy)-1, 1,2,2-tetrafluorohexane-1-sulfonate, triphenylsulfonium 6-(1-adamantylcarbonyloxy)-1,1,2-trifluorobutane-1-sulfonate, tri Phenylsulfonium 2-(4-oxo-1-adamantylcarbonyloxy)-1,1,3,3,3-pentafluoropropane-1-sulfonate, triphenylsulfonium 2-bicyclo[2.2 .1] hepto-2-yl-1,1-difluoroethanesulfonate and the like.

Examples of the tetrahydrothiophenium salt include 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiophenium trifluoromethanesulfonate and 1-(4-n-butoxynaphthalen-1 -yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (4-n-butoxynaphthalen-1-yl)tetrahydrothiophenium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl)tetrahydrothiophenium camphorsulfonate, 1-(6-n-butoxynaphthalen-2-yl)tetrahydrothiopheniumtrifluoromethanesulfonate, 1 -(6-n-butoxynaphthalen-2-yl)tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1-(6-n-butoxynaphthalen-2-yl)tetrahydrothiophenium purple Luoro-n-octanesulfonate, 1-(6-n-butoxynaphthalen-2-yl)tetrahydrothiophenium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2, 2-Tetrafluoroethanesulfonate, 1-(6-n-butoxynaphthalen-2-yl)tetrahydrothiopheniumcamphorsulfonate, 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydro Thiopheniumtrifluoromethanesulfonate, 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1-(3,5-dimethyl-4 -Hydroxyphenyl)tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium 2-bicyclo[2.2.1]hepto -2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium camphorsulfonate, etc. are mentioned.

The content of the photoacid generator in the resist material is preferably in the range of 5 to 50% by mass based on the solid content of the resist material. The solid content of the resist material refers to the total of components other than the solvent in the resist material.

When the resist material of the present invention contains solid materials such as fillers and pigments, it is preferable to disperse and mix them using a dispersing device such as a dissolver, homogenizer, or three roll mill. In addition, in order to remove coarse particles or impurities, filtration may be performed using a mesh filter, a membrane filter, or the like.

The resist material of the present invention can be used for pattern formation in the same way as for general resist materials. As an example thereof, a process of forming a resist film using a resist material, a process of exposing the resist film, and a process of forming a pattern by developing the exposed resist film with a developer may be cited. .

In the step of forming the resist film, the coating method is not particularly limited, and any method such as spin coating, roll coating, flow coating, dip coating, spray coating, or doctor blade coating may be used. When the resist material contains a solvent, a coating film can be obtained by removing the solvent by, for example, prebaking at a temperature of 60 to 150°C after coating. Examples of the object to be coated include a silicon substrate, a silicon carbide substrate, a gallium nitride substrate, a transparent conductive film, and the like, and can be appropriately selected according to the purpose or the like.

In the exposure process, exposure is performed through a mask on which a pattern is depicted. Examples of the exposure light source include infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-rays, and electron beams. Since the resist material of the present invention is highly sensitive and can form a fine pattern, it can be publicly used even for exposure with extreme ultraviolet rays or electron beams.

As the alkali developer used in the development step, those used for general alkali development can be widely used, and examples thereof include inorganic alkaline substances such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-butylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide; Alkaline aqueous solutions, such as cyclic amines, such as pyrrole and piperidine, can be used. Alcohol, surfactant, etc. may be appropriately added to these alkaline developing solutions and used as needed. The alkali concentration of the alkaline developing solution is usually preferably in the range of 2 to 5% by mass, and a 2.38% by mass aqueous solution of tetramethylammonium hydroxide is generally used.

The pattern formation method of this invention is suitably used in the manufacturing process of an electronic device. Examples of the electronic devices include home electric devices, office automation devices, media-related devices, optical devices, communication devices, and the like.

[Example]

Hereinafter, the present invention will be described in detail with examples, but the present invention is not limited thereto.

<GPC measurement conditions>

A measuring device: Tosoh Corporation "HLC-8220 GPC"

Column: Showa Denko Co., Ltd. "Shodex KF802" (8.0 mm Φ × 300 mm)

+ "Shodex KF802" (8.0mmΦ×300mm) manufactured by Showa Denko Co., Ltd.

+ "Shodex KF803" (8.0mmΦ×300mm) manufactured by Showa Denko Co., Ltd.

+ "Shodex KF804" (8.0mmΦ×300mm) manufactured by Showa Denko Co., Ltd.

Column temperature: 40°C

Detector: RI (differential refractometer)

Data processing: "GPC-8020 Model II Version 4.30" manufactured by Tosoh Corporation

Developing solvent: tetrahydrofuran

Flow rate: 1.0 mL/min

Sample: A 0.5% by mass tetrahydrofuran solution of the measurement object filtered through a microfilter (100 μl)

Standard sample: the following monodisperse polystyrene

(Standard sample: monodisperse polystyrene)

"A-500" made by Tosoh Corporation

"A-2500" by Tosoh Corporation

"A-5000" manufactured by Toso Co., Ltd.

"F-1" made by Toso Co., Ltd.

"F-2" made by Toso Co., Ltd.

"F-4" made by Toso Co., Ltd.

"F-10" made by Toso Co., Ltd.

"F-20" made by Toso Co., Ltd.

< ¹³ C-NMR measurement conditions>

Apparatus: JNM-ECA500 manufactured by Nippon Electronics Co., Ltd.

Measurement mode: Decoupling with inverse gate

Solvent: Deuterated dimethyl sulfoxide

Pulse angle: 30° pulse

Sample concentration: 30% by mass

Number of integrations: 4000 times

Standard of chemical shift: Peak of dimethyl sulfoxide: 39.5 ppm

[Synthesis Example 1] Synthesis of compound (a)

293.2 g (2.4 mol) of 2,5-xylenol and 150 g (1 mol) of 4-formylbenzoic acid were put into a 2000 ml four-necked flask equipped with a cooling tube, and dissolved in 500 ml of acetic acid. After adding sulfuric acid 5ml while cooling in an ice bath, it heated to 100 degreeC with the mantle heater, and was made to react, stirring for 2 hours. After completion of the reaction, water was added to the obtained solution to precipitate the crude product. Then, the crude product was redissolved in acetone and reprecipitated by adding water. The precipitate was separated by filtration and vacuum-dried to obtain 292 g of compound (a) as light purple crystals.

As a result of measuring the ¹³ C-NMR spectrum of the obtained compound (a), it was confirmed that it was a compound represented by the following structural formula. Further, the purity calculated from the GPC chart was 95.3%. The GPC chart of compound (a) is shown in FIG. 1, and ^{the 13} C-NMR chart is shown in FIG.

[Example 1] Preparation of metal complex (1) solution

0.20 g (0.48 mmol) of compound (a) obtained in Synthesis Example 1 and zirconium (IV) dibutoxide (manufactured by Matsumoto Fine Chemical Co., Ltd. "Orgatix ZC-580") 0.10 g (0.11 mmol), tetrahydro 20 g of furan was placed in a 30 ml screw tube and mixed at room temperature for 30 minutes. The resulting solution was microfiltered using a disk filter made of polytetrafluoroethylene (PTFE) with a pore size of 0.1 µm to obtain a metal complex (1) solution. The FT-IR spectrum of the obtained metal complex (1) solution is shown in FIG.

[Example 2] Preparation of metal complex (2) solution

The metal complex (2) solution was prepared in the same manner as in Example 1, except that zirconium (IV) dibutoxide was changed to 0.045 g (0.11 mmol) of hafnium (IV) isopropoxide monoisopropylate. got it

[Example 3] Preparation of metal complex (3) solution

A metal complex (3) solution was obtained in the same manner as in Example 1 except that zirconium (IV) dibutoxide was changed to 0.045 g (0.11 mmol) of tetra-n-butoxytin.

[Comparative Synthesis Example 1] Synthesis of Silsesquioxane Resin

25.0 g of ion-exchanged water, 93.6 g of 2-propanol (manufactured by Kanto Chemical Co., Ltd.) and 0.2 g of 35% hydrochloric acid (manufactured by Sigma-Aldrich) were added to a 300 mL four-neck flask, and methyltriethoxysilane ( 75.1 g (0.42 mol) of Shin-Etsu Chemical Co., Ltd.) was added dropwise over 2 hours at 25°C. The mixture was heated up to 40°C and stirred for 3 hours to obtain an oligomer solution. The weight average molecular weight of the obtained oligomer was 1,200. 6.6 g of ion-exchanged water and 1.1 g of 35% hydrochloric acid were added to the obtained oligomer solution, the mixture was heated up to 79°C and stirred for 12 hours. After filtering the obtained liquid mixture with a filter paper with a filtration accuracy of 1 μm, 169 g of n-propyl acetate (manufactured by Kanto Chemical Co., Ltd.) and 169 g of ion-exchanged water were added to the filtrate, followed by liquid separation washing. After washing the n-propyl acetate phase with 169 g of ion-exchanged water until the pH is 4 or higher, filtering with a filter paper with a filtration accuracy of 1 μm, and removing the solvent with a rotary evaporator, 26.9 g of silsesquioxane resin powder was obtained. The weight average molecular weight of the obtained silsesquioxane resin was 4,500.

0.5 g of the previously obtained silsesquioxane resin, 0.4 g of tetra(2,2,6,6-tetramethyl-3,5-heptanedionato) zirconium, 45.0 g of propylene glycol monopropyl ether, and 5.0 g of pure water were mixed into a 100 m screw tube. and mixed at room temperature for 30 minutes. Microfiltration was performed using a disk filter made of polytetrafluoroethylene (PTFE) with a pore size of 0.1 µm to obtain a metal complex (1') solution.

[Examples 4 to 6 and Comparative Example 1]

The previously obtained solutions of metal complexes (1 to 3) and the solution of metal complexes (1') were used as resist materials and evaluated by the following method. Table 1 shows the evaluation results.

[composite evaluation]

5 g of the metal complex solution was placed in a 30 ml heat-resistant tube, heated to 100°C while shaking, and a change in state was observed. All of the solutions of the metal complexes (1 to 3) of the present invention showed immobilization and gelation, while the solution of the metal complexes (1') showed no change in viscosity.

Subsequently, 1 g of a 1N hydrochloric acid aqueous solution was added to the solution of the metal complexes (1 to 3) that had been gelled, and shaken at room temperature for 3 hours to observe a change in state. All of them changed to low-viscosity liquids.

[Create pattern by electron beam]

It was applied to a silicon wafer having a diameter of 6 inches treated with hexamethylenedisilazane using a spin coater. It dried for 60 seconds on a 110 degreeC hot plate, and obtained the thin film of 30 nm thickness.

Using an ultra-high-speed electron beam writing system (“HL-800D” manufactured by Hitachi Seisakusho Co., Ltd.), the high-voltage side voltage (HV) was set to 50 keV, and the exposure amount was changed stepwise in units of 10 μC/cm 2 in a vacuum chamber while 70 Lines and spaces of nm were drawn at a ratio of 1:1.

Immediately after drawing, post-exposure baking (PEB) was performed on a hot plate at 110° C. for 60 seconds, and paddle development was performed for 20 seconds with a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution to obtain a negative pattern.

Further, since the resist material of the present invention is not a chemically amplified resist material by an acid catalyst, the PEB process is not necessarily required, but the reaction of a metal salt to a metal oxide can be promoted by PEB.

[Evaluation of sensitivity]

The obtained pattern was observed with a scanning electron microscope (SEM) and evaluated as follows. The evaluation criteria are as follows.

A: Exposure amount for pattern development is less than 80 μC/cm2

B: Exposure amount that can develop patterns is 80 μC/cm2 or more

made it

[Evaluation of Edge Roughness (LWR)]

In the obtained pattern, edge roughness (LWR) of 70 nm line and space was evaluated with a scanning electron microscope (SEM). The evaluation criteria are as follows.

A: LWR less than 3 nm

B: LWR is 3 nm or more

[Table 1]

Claims (10)

A metal complex characterized by having an anionic compound (A) represented by the following general formula (1) as a ligand.

[In Formula (1), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. m, n and p represent the integer of 0-4 each independently. When a plurality of R ^{1 '} s are present, the plurality of R ¹ 's may be the same as or different from each other. When R ² is plural, plural R ² may be the same as or different from each other. R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on the hydrocarbon group. R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. When R ⁴ is plural, plural R ⁴ may be the same or different.] According to claim 1,
A metal complex whose central metal is any one of zirconium, tin, and hafnium. A composition characterized by containing a compound (a) represented by the following general formula (2) and a metal complex (b).

[In Formula (2), R ¹ and R ² each independently represent an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, an aryl group, an aralkyl group, or a halogen atom. m, n and p represent the integer of 0-4 each independently. When a plurality of R ^{1 '} s are present, the plurality of R ¹ 's may be the same as or different from each other. When R ² is plural, plural R ² may be the same as or different from each other. R ³ represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, or a structural site having at least one substituent selected from an alkoxy group, a halogen group and a hydroxyl group on the hydrocarbon group. R ⁴ represents a hydroxyl group, an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkoxy group, or a halogen atom. When R ⁴ is plural, plural R ⁴ may be the same or different.] According to claim 3,
A composition wherein the metal complex (b) is any one or more of a zirconium complex, a tin complex, and a hafnium complex. According to claim 3,
A composition in which the metal complex (b) is a metal alkoxide. A resist material containing the metal complex according to claim 1 or 2. According to any one of claims 3 to 5,
A composition that is a resist material. A step of forming a resist film using the resist material according to claim 6 or 7;
a step of exposing the resist film;
and forming a pattern by developing the exposed resist film using a developing solution. According to claim 8,
The pattern formation method in which the said exposure is exposure with an electron beam or extreme ultraviolet. A method for manufacturing an electronic device including the pattern formation method according to claim 8 or 9.

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