TWI684589B - Developing solution for photolithography and pattern forming method - Google Patents

Abstract

Provided is a developing method for photolithography and a resist pattern formation method that are excellent in suppressing migration or suppressing oxidation on the surface of a substrate or wiring.

A developer for photolithography comprising (A) an imidazole compound represented by the following general formula (1), and (B) water and/or an organic solvent, (wherein R ¹ is a hydrogen atom or an alkyl group, R ² Is an aromatic group which may have a substituent, R ³ is an alkylene group which may have a substituent, and R ⁴ is independently a halogen atom, a hydroxyl group, a mercapto group, a thioether group, a silane group, a silanol group, a nitro group, a (Nitro, sulfonate, phosphine, phosphinyl, phosphonate, or organic, n is an integer from 0 to 3).

Description

Developer solution for photolithography and method for forming resist pattern

The present invention relates to a method for forming a resist pattern using a developer for photolithography and a developer for the photolithography.

In response to the requirements of miniaturization and high performance of various electronic devices, printed wiring boards or various electrical and electronic components are being miniaturized and integrated. As a result, printed wiring boards or electrical and electronic components are becoming thinner for metal wiring, or the spacing between wirings is becoming narrower. Such printed wiring boards or various electrical and electronic components are excellent in conductivity or workability, so as the substrate or wiring materials, copper, silver, tin, lead, zinc, aluminum, Metals such as nickel, gold or alloys thereof.

When processing printed wiring boards or electrical and electronic components into various devices, substrates or wires made of metal, for example, surface mount, or use photosensitive compositions on circuits to form resist patterns In this case, it is often heated for curing after development. The heating of the substrate or wiring made of metal has the following problems.

First, the surface of the substrate or wiring may be oxidized due to heating. Since the difference in resistance between metal and metal oxide is large, when the surface of a thin circuit is oxidized, deviations in circuit resistance are likely to occur. The deviation of the circuit resistance will greatly affect the performance of the product. Also, when the surface of the circuit is oxidized, the wettability of the surface of the circuit and the solder will deteriorate, making soldering on the circuit difficult.

Furthermore, when a substrate or wiring made of metal is heated, metal ions may be eluted (migration) on the surface of the substrate due to moisture on the surface of the substrate, etc. Into a dendritic crystal. When the interval between the wirings is narrow, the formation of dendritic crystals of the metal compound due to migration has the problem that wiring short-circuits are likely to occur.

In order to solve the above problems, a method of surface-treating the metal before heating has been proposed. Specifically, a method for surface-treating wiring made of copper or an alloy containing copper using a surface treatment liquid containing an imidazole compound, iron ions, and a phosphonic acid chelating agent has been proposed (Patent Document 1); or A method of surface-treating wiring made of copper or an alloy containing copper using an aqueous solution of an azole compound as a surface treatment liquid (Patent Document 2).

[Prior Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2014-101554

[Patent Document 2] Japanese Unexamined Patent Publication No. 2012-244005

However, even if it is treated with a surface treatment liquid as described in Patent Documents 1 and 2, the temperature or the number of times of heating of the wiring may not be able to suppress migration well or the oxidation of the wiring surface. In addition, the effect of suppressing migration or suppressing the oxidation of the wiring surface is desired if these effects can be obtained by the developer used before the hardening of the resist pattern.

The present invention is an invention in view of the above problems, and provides a developer for photolithography with an excellent effect of suppressing migration or suppressing oxidation of the surface of a substrate or wiring, and a resist diagram using the developer for photolithography Type formation method for the purpose.

The present inventor found that the designated position is a "specified structure saturated fatty acid or saturated fatty acid ester" substituted with an aromatic group having a specified structure and an imidazolyl group which may have a substituent. By using the saturated fatty acid or saturated The photolithography of a fatty acid ester develops a photosensitive resin composition layer formed on a metal-made substrate or wiring with a developer to solve the above-mentioned problems, and thus the present invention has been completed. Specifically, the present invention provides the following.

The first developing solution for photolithography of the present invention comprises an imidazole compound represented by the following general formula (1), and (B) water and/or an organic solvent,

(In the formula, R ¹ is a hydrogen atom or an alkyl group, R ² is an aromatic group which may have a substituent, R ³ is an alkylene group which may have a substituent, and R ⁴ is independently a halogen atom, a hydroxyl group, a mercapto group, Thioether group, silane group, silanol group, nitro group, nitroso group, sulfonate group, phosphine group, phosphine oxide group, phosphonate group, or organic group, n is an integer of 0~3).

The method for forming a resist pattern of the second aspect of the present invention uses the developer of the first aspect of the present invention for photolithography.

According to the present invention, it is possible to provide a developing solution for photolithography which is excellent in the effect of suppressing migration or suppressing the oxidation of the surface of a substrate or wiring, and a method for forming a resist pattern using the developing solution for photolithography.

[Best form for carrying out the invention]

≪Development solution for photolithography≫

The developer for photolithography of the present invention contains (A) the following general formula (1) The represented imidazole compound, and (B) water and/or organic solvent.

(A) Imidazole compound represented by formula (1)

When the imidazole compound represented by formula (1) (hereinafter referred to as "imidazole compound") is brought into contact with a metal, the imidazole compound represented by formula (1) reacts with metal ions to form a chemical film on the surface of the metal . When the chemical conversion film is formed on the surface of the wiring made of metal, the short circuit between the wirings caused by the migration of the metal or the oxidation of the metal can be suppressed.

(In formula (1), R ¹ is a hydrogen atom or an alkyl group, R ² is an aromatic group which may have a substituent, R ³ is an alkylene group which may have a substituent, and R ⁴ is a halogen atom, a hydroxyl group, a mercapto group, Thioether group, silane group, silanol group, nitro group, nitroso group, sulfonate group, phosphine group, phosphine oxide group, phosphonate group, or organic group, n is an integer of 0~3).

In formula (1), R ¹ is a hydrogen atom or an alkyl group. When R ¹ is an alkyl group, the alkyl group may be a straight chain alkyl group or a branched chain alkyl group. The carbon number of the alkyl group is not particularly limited, but it is preferably 1-20, preferably 1-10, and more preferably 1-5.

Specific examples of R ¹ as a suitable alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n -Pentyl, isopentyl, tert-pentyl, n-hexyl, n-heptyl, n-octyl, 2-ethyl-n-hexyl, n-nonyl, n-decyl, n-undecyl Base, n-dodecyl, n-tridecyl, n-tetradecyl, n-fifteen, n-hexadecyl, n-seventh, n-octadecyl, n-nineteen, And n-twenty base.

In formula (1), R ² is an aromatic group which may have a substituent. The "aromatic group which may have a substituent" may be an aromatic hydrocarbon group which may have a substituent, or an aromatic heterocyclic group which may have a substituent.

The type of aromatic hydrocarbon group is not particularly limited as long as the purpose of the present invention is not impaired. The aromatic hydrocarbon group may be a monocyclic aromatic group, or may be formed by condensation of more than 2 aromatic hydrocarbon groups, or may be formed by bonding more than 2 aromatic hydrocarbon groups by a single bond. As the aromatic hydrocarbon group, phenyl, naphthyl, biphenyl, anthryl, and phenanthryl are preferred.

The type of aromatic heterocyclic group is not particularly limited within the scope not detracting from the purpose of the present invention. The aromatic heterocyclic group may be a monocyclic group or a polycyclic group. The aromatic heterocyclic group is preferably pyridyl, furyl, thienyl, imidazolyl, pyrazolyl, oxazolyl, thiazolyl, isoxazolyl, isothiazolyl, benzoxazolyl, benzo Thiazolyl and benzimidazolyl.

Examples of the substituent that the phenyl group, polycyclic aromatic hydrocarbon group, or aromatic heterocyclic group may have include a halogen atom, a hydroxyl group, a mercapto group, a thioether group, a silane group, a silanol group, a nitro group, a nitroso group, and a nitroso group Sulfonic acid group, sulfonic acid group, sulfonic acid group, phosphine group, phosphine oxide group, phosphinyl group, phosphonic acid group, amine group, ammonium group, and organic group. When the phenyl group, polycyclic aromatic hydrocarbon group, or aromatic heterocyclic group has a plurality of substituents, the plurality of substituents may be the same Or different.

When the substituent of the aromatic group is an organic group, examples of the organic group include alkyl groups, alkenyl groups, cycloalkyl groups, cycloalkenyl groups, aryl groups, and aralkyl groups. The organic group may contain a bond or a substituent other than a hydrocarbon group such as a hetero atom in the organic group. In addition, the organic group may be arbitrarily linear, branched, or cyclic. The organic group is usually monovalent, but when a ring structure is formed, it may be an organic group of divalent or higher.

If there is a substituent on the carbon atom adjacent to the aromatic group, the two substituents bonded to the adjacent carbon atom may form a ring structure by bonding them. Examples of the cyclic structure include aliphatic hydrocarbon rings or aliphatic rings containing heteroatoms.

When the substituent of the aromatic group is an organic group, the bond included in the organic group is not particularly limited as long as the effect of the present invention is not impaired. The organic group may also contain oxygen atoms, nitrogen atoms, Bonding of heteroatoms such as silicon atoms. Specific examples of the bond containing a hetero atom include ether bond, thioether bond, carbonyl bond, thiocarbonyl bond, ester bond, amide bond, urethane bond, and imine bond (-N=C( -R)-, -C(=NR)-: R represents a hydrogen atom or an organic group), carbonate bond, sulfonyl bond, sulfinyl bond, azo bond, etc.

As the bond containing a hetero atom which the organic group may have, from the viewpoint of the heat resistance of the imidazole compound represented by formula (1), an ether bond, a thioether bond, a carbonyl bond, a thiocarbonyl bond, an ester bond is preferred , Amide bond, amine bond (-NR-: R represents a hydrogen atom or a monovalent organic group) urethane bond, imine bond (-N=C(-R)-, -C(=NR )-: R represents a hydrogen atom or a monovalent organic Group), carbonate bond, sulfonyl bond, sulfinyl bond.

When the organic group is a substituent other than a hydrocarbon group, the type of the substituent other than the hydrocarbon group is not particularly limited as long as the object of the present invention is not impaired. Specific examples of the substituent other than the hydrocarbon group include a halogen atom, a hydroxyl group, a mercapto group, a thioether group, a cyano group, an isocyano group, a cyano group, an isocyanato group, a thiocyanato group, and an isocyano group. Thiocyanate, silane, silanol, alkoxy, alkoxycarbonyl, amine, monoalkylamine, dialkylaluminum, monoarylamine, diarylamine, amine Methyl, thioamine, methyl, nitro, nitroso, carboxylate, acetyl, oxy, sulfinyl, sulfonate, phosphinyl, phosphinyl, phosphonate, Alkyl ether group, alkenyl ether group, alkyl sulfide group, alkenyl sulfide group, aryl ether group, aryl sulfide group, etc. The hydrogen atom contained in the above substituent may be substituted with a hydrocarbon group. In addition, the hydrocarbon group included in the substituent may be any of linear, branched, and cyclic.

The substituents of the phenyl group, polycyclic aromatic hydrocarbon group, or aromatic heterocyclic group are preferably an alkyl group having 1 to 12 carbon atoms, an aryl group having 1 to 12 carbon atoms, and an alkyl group having 1 to 12 carbon atoms. Oxygen groups, aryloxy groups having 1 to 12 carbon atoms, arylamine groups having 1 to 12 carbon atoms, and halogen atoms.

As R ² , the imidazole compound represented by the formula (1) can be synthesized cheaply and easily, and the solubility of the imidazole compound in water or organic solvents is improved, and the phenyl group and the furyl group which can have separate substituents , Thienyl is preferred.

In formula (1), R ³ is an alkylene group which may have a substituent. The substituent which the alkylene group may have is not particularly limited as long as the object of the present invention is not impaired. Specific examples of the substituent that the alkylene group may have include a hydroxyl group, an alkoxy group, an amine group, a cyano group, and a halogen atom. The alkylene group may be a linear alkylene group or a branched alkylene group, preferably a linear alkylene group. The carbon number of the alkylene group is not particularly limited, but it is preferably 1-20, preferably 1-10, and more preferably 1-5. Still, the carbon number of the alkylene group does not include the carbon atom of the substituent bonded to the alkylene group.

The alkoxy group as a substituent to which the alkylene group is bonded may be a linear alkoxy group or a branched alkoxy group. The carbon number of the alkoxy group as a substituent is not particularly limited, but it is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 3.

The amine group as a substituent to which the alkylene group is bonded may be a monoalkylamine group or a dialkylamine group. The alkyl group contained in the monoalkylamine group or the dialkylamine group may be a linear alkyl group or a branched alkyl group. The carbon number of the alkyl group contained in the monoalkylamine group or the dialkylamine group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 3.

As specific examples of R ³ as a suitable alkylene group, for example, methylene, ethane-1,2-diyl, n-propane-1,3-diyl, n-propane-2,2-di Group, n-butane-1,4-diyl, n-pentane-1,5-diyl, n-hexane-1,6-diyl, n-heptane-1,7-diyl, n-octane-1,8-diyl, n-nonane-1,9-diyl, n-decane-1,10-diyl, n-undecane-1,11-diyl, n -Dodecane-1,12-diyl, n-tridecane-1,13-diyl, n-tetradecane-1,14-diyl, n-pentadecan-1,15-diyl , N-hexadecane-1,16-diyl, n-heptadecane-1,17-diyl, n-octadecane-1,18-diyl, n-nonadecane-1,19- Diyl, and n-eicosane-1,20-diyl.

R ⁴ is a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silane group, a silanol group, a nitro group, a nitroso group, a sulfonate group, a phosphine group, a phosphine oxide group, a phosphonate group, or an organic group, n is 0 Integer of ~3. When n is an integer from 2 to 3, a plurality of R ⁴ may be the same or different.

When R ⁴ is an organic group, the organic group is the same as the organic group which may have a substituent as the aromatic group in R ² .

When R ⁴ is an organic group, the organic group is preferably an alkyl group, an aromatic hydrocarbon group, and an aromatic heterocyclic group. As the alkyl group, a linear or branched alkyl group having 1 to 8 carbon atoms is preferred, and a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are also preferred. As the aromatic hydrocarbon group, phenyl, naphthyl, biphenyl, anthracenyl, and phenanthrenyl are preferred, and phenyl and naphthyl are preferred, and phenyl is particularly preferred. The aromatic heterocyclic group is preferably pyridyl, furyl, thienyl, imidazolyl, pyrazolyl, oxazolyl, thiazolyl, isoxazolyl, isothiazolyl, benzoxazolyl, benzo Thiazolyl and benzimidazolyl are preferably furyl and thienyl.

When R ⁴ is an alkyl group, the bonding position of the alkyl group on the imidazole ring is preferably any of the 2-position, 4-position, and 5-position, and more preferably the 2-position. When R ⁴ is an aromatic hydrocarbon group and an aromatic heterocyclic group, the bonding position of these groups on the imidazole is preferably 2-position.

Among the imidazole compounds represented by the above formula (1), the compounds represented by the following formula (1-1) are preferred because they are inexpensive and can be easily synthesized, and have excellent solubility in water or organic solvents. It is also preferably a compound represented by formula (1-1) and R ³ is methylene.

(In formula (1-1), R ¹ , R ³ , R ⁴ , and n are the same as formula (1), and R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ are independently hydrogen atoms , Halogen atom, hydroxyl group, mercapto group, thioether group, silane group, silanol group, nitro group, nitroso group, sulfinic acid group, sulfonic acid group, sulfonate group, phosphine group, phosphinyl group, phosphinyl group, A phosphonate group, an amine group, an ammonium group, or an organic group, but at least one of R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ is a group other than a hydrogen atom).

When R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ are organic groups, the organic group is the same as the organic group having R ² in formula (1) as a substituent. Regarding the solubility of the imidazole compound in the solvent, R ⁵ , R ⁶ , R ⁷ , and R ^{8 are} preferably hydrogen atoms.

Among them, at least one of R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ is preferably the following substituent, and R ⁹ is particularly preferably the following substituent. When R ⁹ is a substituent described below, R ⁵ , R ⁶ , R ⁷ , and R ^{8 are} preferably hydrogen atoms.

-OR ¹⁰

(R ¹⁰ is a hydrogen atom or an organic group).

When R ¹⁰ is an organic group, the organic group is the same as the organic group that R ² in formula (1) has as a substituent. R ^{10 is} preferably an alkyl group, and more preferably an alkyl group having 1 to 8 carbon atoms, particularly preferably an alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.

Among the compounds represented by the above formula (1-1), the compounds represented by the following formula (1-1-1) are preferred.

(In formula (1-1-1), R ¹ , R ⁴ , and n are the same as in formula (1), and R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ are independently hydrogen atoms, Hydroxy, mercapto, thioether, silane, silanol, nitro, nitroso, sulfinyl, sulfonate, sulfonate, phosphine, phosphinyl, phosphinyl, phosphonate, An amine group, an ammonium group, or an organic group, but at least one of R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ is a group other than a hydrogen atom).

Among the compounds represented by the formula (1-1-1), it is preferred that at least one of R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ is a group represented by the aforementioned -OR ¹⁰ , The base represented by R ¹⁵ as -OR ¹⁰ is particularly preferred. When R ¹⁵ is a group represented by -OR ¹⁰ , R ¹¹ , R ¹² , R ¹³ , and R ^{14 are} preferably hydrogen atoms.

The method for synthesizing the imidazole compound represented by the above formula (1) is not particularly limited. For example, by reacting a halogen-containing carboxylic acid derivative represented by the following formula (I) with an imidazole compound represented by the following formula (II) according to a conventional method, the above formula can be synthesized by performing imidazolylation (1) represented imidazole Compound.

(In formula (I) and formula (II), R ¹ , R ² , R ³ , R ⁴ and n are the same as in formula (1). Hal in formula (I) is a halogen atom).

In addition, when the imidazole compound is a compound represented by the formula (1) and R ³ is a methylene group, that is, when the imidazole compound is a compound represented by the following formula (1-2), it can also be explained by the following Michael addition reaction method to synthesize imidazole compounds.

(In formula (1-2), R ¹ , R ² , R ⁴ and n are the same as in formula (1)).

Specifically, for example, a 3-substituted acrylic acid derivative represented by the following formula (III) and an imidazole compound represented by the above formula (II) are mixed in a solvent, and obtained by causing Michael addition reaction The imidazole compound represented by the above formula (1-2).

(In formula (III), R ¹ , R ² , R ⁴ and n are the same as in formula (1)).

Furthermore, by adding an imidazolyl group-containing 3-substituted acrylic acid derivative represented by the following formula (IV) to a solvent containing water, an imidazole compound represented by the following formula (1-3) can be obtained.

(In Formula (IV) and Formula (1-3), R ² , R ⁴ and n are the same as Formula (1)).

In this case, by hydrolysis of the 3-substituted acrylic acid derivative represented by the above formula (IV), the imidazole compound represented by the above formula (II) and the 3-substituted acrylic acid represented by the following formula (V) can be produced . Then, a Michael addition reaction occurs between the 3-substituted acrylic acid represented by the following formula (V) and the imidazole compound represented by the above formula (II) to produce the imidazole compound represented by the above formula (1-3).

(In formula (V), R ² is the same as formula (1)).

Examples of suitable specific examples of the imidazole compound represented by formula (1) include the following.

(B) Water and/or organic solvents

The developer for photolithography of the present invention contains (B) water and/or an organic solvent in addition to (A) the imidazole compound represented by the above formula (1).

[Organic solvents]

For the case where negative-type development is performed under a system where the exposed portion is photolithography such as insoluble in an organic solvent, or when the unexposed portion is subjected to a system based on photolithography such as insoluble in organic solvent In the case of type development, an organic developer containing an organic solvent as a developer can be used.

As the organic developer that can be used when performing solvent development, polar solvents such as ketone solvents, alcohol solvents, amide solvents, ether solvents, and ester solvents, and hydrocarbon solvents can be used.

In the present invention, the ketone-based solvent refers to a solvent having a ketone group in the molecule, the ester-based solvent refers to a solvent having an ester group in the molecule, and the alcohol-based solvent refers to a solvent having an alcoholic hydroxyl group in the molecule The so-called amide-based solvent means a solvent having an amide group in the molecule, and the so-called ether-based solvent means a solvent having an ether bond in the molecule. Among these, there are also solvents having a plurality of the above-mentioned functional groups in one molecule, but this case is also equivalent to any solvent containing the functional groups of the solvent. For example, the diethylene glycol monomethyl ether system corresponds to any of the alcohol solvents and ether solvents in the above classification. In addition, the hydrocarbon-based solvent means a hydrocarbon solvent having no substituent.

Examples of the ketone-based solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methyl amyl ketone), 4-heptanone, and 1-hexane Ketone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetone acetone, acetone acetone, ionone, Diacetone alcohol, ethyl alcohol, styrene Ketone, methyl naphthyl ketone, isophorone, propylene carbonate, γ-butyrolactone, etc.

Examples of the ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, amyl acetate, isoamyl acetate, and ethyl methoxyacetate. Ester, ethyl ethoxyacetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, ethylene glycol monopropyl ether acetate, ethyl acetate Glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol mono Ethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxy Propionate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl Acetate, 3-ethyl-3-methoxybutyl acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate Ester, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate Ester, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, Propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, 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, 2 -Methyl hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate , Propyl-3-methoxypropionate, γ- Butyrolactone, etc.

Examples of the alcohol-based solvent include methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, n-hexanol, and n-heptanol. , N-octanol, n-decanol, 4-methyl-2-pentanol (MIBC: methyl isobutyl methanol), 3-methoxy-1-butanol and other alcohols, or ethylene glycol , Diethylene glycol, triethylene glycol and other ethylene glycol solvents, or ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether , Methoxymethyl butanol, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether , Propylene glycol monophenyl ether and other hydroxy glycol ether solvents. Among these, it is preferable to use a glycol ether-based solvent.

As the ether-based solvent, for example, in addition to the glycol ether-based solvent containing the above-mentioned hydroxyl group, for example, dibutyl ether, ethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethyl ether Hydroxy glycol ether solvents such as glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diisoamyl ether, diisobutyl ether, dioxane , Tetrahydrofuran, anisole, perfluoro-2-butyltetrahydrofuran, perfluorotetrahydrofuran, 1,4-dioxane, etc. It is preferable to use a glycol ether-based solvent.

As the amide-based solvent, for example, dimethyl sulfoxide, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, hexamethyl Phosphamidylamide, 1,3-dimethyl-2-imidazolidinone, etc.

Examples of the hydrocarbon-based solvent include pentane, hexane, octane, decane, 2,2,4-trimethylpentane, 2,2,3-trimethylhexane, and perfluorohexane Aliphatic hydrocarbon solvents such as alkanes, perfluoroheptane, limonene, and pinene, toluene, xylene, ethylbenzene, propylbenzene, 1-methylpropylbenzene, 2-methylpropylbenzene, dimethylbenzene, Aromatic hydrocarbon solvents such as diethylbenzene, ethylmethylbenzene, trimethylbenzene, 1,2,4-trimethylbenzene, ethyldimethylbenzene, and dipropylbenzene.

The above-mentioned solvent system may be mixed in plural, or may be used after being mixed with a solvent other than the above or water.

Among these, ester solvents are preferred. As the ester-based solvent, it is preferable to use the solvent represented by the general formula (4) described later or the solvent represented by the general formula (5) described later, and it is more preferable to use the solvent represented by the general formula (5).

As a developer that can be used when performing solvent development, it is preferable to use a solvent represented by the following general formula (4).

In the general formula (4), R ^S1 and R ^S2 are each independently represented as a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group, or a halogen atom. The R ^S1 and R ^S2 systems may be bonded to each other to form a ring. The R ^S1 and R ^S2 systems are preferably a hydrogen atom or an alkyl group, and the alkyl system of R ^S1 and R ^S2 may be substituted with a hydroxyl group, a carbonyl group, or a cyano group.

Examples of the solvent represented by general formula (4) include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, and ethyl acetate. Isoamyl acid, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, 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, 2- Methyl hydroxypropionate, ethyl 2-hydroxypropionate, etc.

Among these, the solvent represented by general formula (4) is preferably R ^S1 and R ^S2 as unsubstituted alkyl groups, alkyl acetate is more preferable, and butyl acetate is particularly preferable.

The solvent system represented by general formula (4) can also be used in combination with one or more other solvents. The combined solvent in this case is not particularly limited as long as it is not separated from the solvent represented by general formula (4) and can be mixed, and the solvents represented by general formula (4) can be used in combination with each other, or the general The solvent represented by formula (4) is mixed and used in a solvent selected from other ester-based solvents, ketone-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents. More than one type of solvent can be used in combination, but one type is preferable in terms of obtaining stable performance. When one kind of mixed solvent is used, the mixing ratio of the solvent represented by general formula (4) and the combined solvent is usually 20:80~99:1, preferably 50:50~97:3, It is more preferably 60:40~95:5, and most preferably 60:40~90:10.

As a developer that can be used when performing solvent development, it is preferable to use a solvent represented by the following general formula (5).

In the general formula (5), R ^S3 and R ^S5 independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group, or a halogen atom.

R ^S3 and R ^S5 systems may be bonded to each other to form a ring.

R ^S3 and R ^S5 are preferably hydrogen atoms or alkyl groups.

R ^S4 represents alkylene or cycloalkylene. R ^S4 is preferably a hydrogen atom or an alkyl group.

The alkyl system of R ^S3 , R ^S4 and R ^S5 may be substituted by a hydroxyl group, a carbonyl group, a cyano group or the like.

In the general formula (5), the alkylene system of R ^S4 may have an ether bond in the alkylene chain.

Examples of the solvent represented by general formula (5) include ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, and ethylene glycol. Monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether Ether ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methyl-3- Methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, ethyl methoxyacetate, Ethoxyethyl acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl 3-Methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate , 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl- 3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4- Methoxypentyl acetate, etc.

Among these, the solvent represented by general formula (5) is preferably R ^S2 , R ^S4 and R ^S5 as unsubstituted alkyl groups, and particularly preferably propylene glycol monomethyl ether acetate (PGMEA).

The solvent system represented by general formula (5) may be used in combination with one or more other solvents. The combined solvent in this case is not particularly limited as long as it is not separated from the solvent represented by general formula (5) and can be mixed, and the solvents represented by general formula (5) can be used in combination with each other, or The solvent represented by general formula (5) is mixed and used in a solvent selected from other ester-based solvents, ketone-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents. More than one type of solvent can be used in combination, but one type is preferable in terms of obtaining stable performance. When one kind of mixed solvent is used, the mixing ratio of the solvent represented by general formula (5) and the combined solvent is usually 20:80~99:1, preferably 50:50~97:3, It is more preferably 60:40~95:5, and most preferably 60:40~90:10.

In addition, it is preferable to use a solvent composed of a compound (S) represented by the following general formula (6) as a developer that can be used when performing solvent development.

(In formula (6), R ^S6 and R ^S7 are independently C 1-3 alkyl groups, and R ^S8 is the following formula (6-1) or the following formula (6-2):

The basis of the said. In formula (6-1), R ^S9 is a hydrogen atom or a hydroxyl group, and R ^S10 and R ^S11 are each independently an alkyl group having 1 to 3 carbon atoms. In formula (6-2), R ^S12 and R ^S13 are each independently a hydrogen atom or a C 1-3 alkyl group).

Among the compounds (S) represented by formula (6), specific examples when R ^S8 is a group represented by formula (6-1) include N,N,2-trimethylpropionamide, N-ethyl, N,2-dimethylpropylamide, N,N-diethyl-2-methylpropylamide, N,N,2-trimethyl-2-hydroxypropylamide, N -Ethyl-N,2-dimethyl-2-hydroxypropylamide, and N,N-diethyl-2-hydroxy-2-methylpropylamide, etc.

Among the compounds (S) represented by the formula (6), as a specific example when R ^S8 is a group represented by the formula (6-2), N,N,N',N'-tetramethyl can be exemplified Urea, N,N,N',N'-tetraethylurea, etc.

In the example of the above compound (S), as a particularly preferred one is N,N,2-trimethylpropylamide (DMIB), and N,N,N',N'-tetramethylurea (TMU) are preferred.

The solvent system composed of the compound (S) represented by the general formula (6) may be used in combination with one or more other solvents. In this case, the combined solvent is not particularly limited as long as it is not separated from the solvent represented by the general formula (6) and can be mixed, and the solvents represented by the general formula (6) can be used in combination with each other, or The solvent represented by general formula (6) is mixed and used in a solvent selected from other ester-based solvents, ketone-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents. More than one type of solvent can be used in combination, but one type is preferable in terms of obtaining stable performance. When one kind of mixed solvent is used, the mixing ratio of the solvent represented by general formula (6) and the combined solvent is usually 20:80~99:1, preferably 50:50~97:3, and It is preferably 60:40~95:5, and most preferably 60:40~90:10.

Examples of the organic solvent that can be used with the solvent made of the compound (S) include N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrole. Nitrogen-containing polar solvents such as pyridone, hexamethylphosphoramide, 1,3-dimethyl-2-imidazolidinone; methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone Ketones such as ketones; γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, α-methyl-γ-butyrolactone, ethyl lactate , Esters of methyl acetate, ethyl acetate, and oxalic acid-n-butyl; cyclic ethers such as dioxane and tetrahydrofuran; cyclic esters such as ethylene carbonate and propylene carbonate; toluene , And aromatic hydrocarbons such as xylene; sulfoxides such as dimethyl sulfoxide.

As the solvent used in the solvent development, from the viewpoint of reducing the cost of the solvent used for development, it is preferable to use an organic solvent that does not contain a halogen atom. The content of the organic solvent excluding halogen atoms in the total weight of all solvents used in the solvent development is usually 60% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more, Tejia is more than 97% by mass.

The boiling point of the solvent used in the solvent development is preferably 50°C or higher and less than 250°C.

The flash point of the solvent used in the solvent development is preferably 200°C or higher.

[water]

As the (B) water and/or organic solvent contained in the developer for photolithography of the present invention, it is preferred to use water, or a mixture of water and an organic solvent, but as the solvent system, only water is used as It's better. The developer for photolithography of the present invention, when water is used, especially when only water is used as a solvent, usually contains the following (C) basic compound, by containing (C) basic The compound can thus be used as an alkaline developer. Such an alkaline developing solution is for the case where negative type development is performed in a system where the exposed portion is photolithography such as insoluble in alkaline developing solution, or when the unexposed portion is insoluble in alkaline developing solution In the case of positive type development under the system of photolithography, it is suitable for use.

(C) Basic compounds

The developer for photolithography of the present invention contains (A) the imidazole compound represented by the above formula (1), (B) water and/or an organic solvent, and may further contain (C) a basic compound. When the developer for photolithography of the present invention contains (C) an alkaline compound, it can usually be used as an alkaline developer, and water is preferably used as the (B) water and/or organic solvent.

As the (C) basic compound system, a conventionally known basic compound can be used. Examples of such basic compounds include basic compounds containing alkali metals and organic bases not containing metal ions.

Examples of alkaline compounds containing alkali metals include hydroxides, carbonates, bicarbonates, phosphates, and pyrophosphates of alkali metals such as lithium, sodium, and potassium. Specifically, sodium hydroxide, Inorganic bases such as potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, etc.

Examples of organic bases that do not contain metal ions include first amines such as ethylamine and n-propylamine; second amines such as diethylamine and di-n-butylamine; and triethyl Tertiary amines such as basic amines, methyldiethylamine, etc.; tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide (TBAH), trimethylammonium hydroxide (2-hydroxyethyl) ammonium, triethyl (2-hydroxyethyl) ammonium hydroxide, tripropyl (2-hydroxyethyl) ammonium hydroxide, trimethyl (1-hydroxypropyl) hydroxide Fourth-grade ammonium salts such as ammonium; alcohol amines such as dimethylethanolamine and triethanolamine; etc. In addition, the substituents are linear, branched, or cyclic amines including first-, second-, and third-stage amines. Specifically, 1,3-diaminopropane and the like can also be exemplified. Diaminoalkanes, arylamines such as 4,4'-diaminodiphenylamine, and alkylamines such as N,N'-diaminodialkylamine. Also, there are 3 to 5 carbon atoms in the ring skeleton Heterocyclic bases with 1 or 2 heteroatoms selected from nitrogen, oxygen, sulfur, specifically, pyrrole, pyridine, pyrazine, pyrrolidine, piperidine, pyrrolidone, morpholin, For oxazole and thiazole, cyclic amines such as pyrrole and piperidine are preferred. Among such organic bases, a fourth-order ammonium compound, particularly tetramethylammonium hydroxide (TMAH) is preferred. These organic alkali systems may be used alone or in combination of two or more.

Furthermore, in the said alkaline aqueous solution, alcohols and surfactants can also be added and used in an appropriate amount.

The alkali concentration of the alkali developer is usually 0.1 to 20% by mass.

The pH of the alkaline developer is usually 10.0 to 15.0.

In particular, a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH) is suitable.

Other ingredients

In the organic solvent developer, well-known additives can be formulated according to the needs. Examples of additives include surfactants. The surfactant is not particularly limited, and for example, ionic or nonionic fluorine-based and/or silicon-based surfactants can be used.

The anionic surfactant is not particularly limited, and a conventionally known surfactant having an anionic group can be used. As such an anionic surfactant, for example, as an anionic group, a surfactant having a carboxylic acid group, a sulfonic acid group, or a phosphoric acid group can be exemplified.

Specifically, a higher fatty acid having a C 8-20 alkyl group, a higher alkyl sulfate, a higher alkyl sulfonic acid, a higher alkyl aromatic Sulfonic acid, other surfactants with sulfonic acid groups, higher alcohol phosphate esters, or salts thereof. Here, the alkyl group of the anionic surfactant may be either linear or branched, and may have a phenylene group or an oxygen atom in the branched chain, or an alkyl group. A part of the hydrogen atoms possessed by the group may be substituted by a hydroxyl group or a carboxyl group.

Specific examples of the higher fatty acid include dodecanoic acid, myristic acid, and stearic acid. Specific examples of the higher alkyl sulfate include decyl sulfate and dodecyl sulfate. In addition, examples of the above-mentioned higher alkylsulfonic acid include decanesulfonic acid, dodecanesulfonic acid, tetradecanesulfonic acid, pentadecanesulfonic acid, and stearic acid sulfonic acid.

In addition, as specific examples of the higher alkylarylsulfonic acid, dodecylbenzenesulfonic acid, decylnaphthalenesulfonic acid, and the like can be mentioned.

Furthermore, as other surfactants having a sulfonic acid group, for example, alkyl diphenyl ether disulfonic acid such as dodecyl diphenyl ether disulfonic acid and the like, dioctyl sulfosuccinate, etc. Alkyl sulfosuccinate etc.

Examples of higher alcohol phosphates include palmityl phosphate, castor oil alkyl phosphate, coconut oil alkyl phosphate, and the like.

Among the above anionic surfactants, it is preferable to use a surfactant having a sulfonic acid group. Specific examples include alkylsulfonic acid, alkylbenzenesulfonic acid, olefinsulfonic acid, and alkyldibenzene. Ether sulfonic acid, alkyl naphthalene sulfonic acid, dialkyl sulfosuccinate, etc. Among these, it is preferable to use alkylsulfonic acid, alkylbenzenesulfonic acid, alkyldiphenyl ether disulfonic acid, and dialkylsulfosuccinate. The average carbon number of the alkyl group of the alkylsulfonic acid is preferably 9-21, and 12-18 is even more preferable. Also, the average carbon of the alkyl group of alkylbenzenesulfonic acid The number system is preferably 6~18, and 9~15 is more preferable. The average carbon number of the alkyl group of the alkyl diphenyl ether disulfonic acid is preferably 6 to 18, and 9 to 15 is even more preferable. Furthermore, the average carbon number of the alkyl group of the dialkyl sulfosuccinate is preferably 4-12, and 6-10 is even more preferable.

Examples of the nonionic surfactant system include polyoxyethylene alkyl ether and acetylene-based nonionic surfactant. The nonionic surfactant system is preferably water-soluble. The range of HLB7~17 is better. When the HLB is small and the water solubility is insufficient, it can also be mixed with other active agents to make it water soluble.

Examples of commercially available surfactants that can be used include, for example, F-Top EF301, EF303, (manufactured by Shin-Akita Chemical Industry Co., Ltd.), Fluorad FC430, 431 (manufactured by Sumitomo 3M Co., Ltd.), MEGAFACE F171, F173, F176 , F189, R08 (Dainippon Ink Chemical Industry Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troy Sol S-366 (Troy Chemical (Co., Ltd.) ) Made) such as fluorine-based surfactants or silicon-based surfactants. In addition, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicone-based surfactant.

In addition, as the surfactant, in addition to the aforementioned well-known ones, fluorine produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method) can be used Surfactant for polymers with fluoroaliphatic groups derived from aliphatic compounds.

As a polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly(oxyalkylene group)) acrylate and/or (poly(oxyalkylene group)) methacrylate is Better, even if it is irregular It can also be block copolymerized. In addition, as the poly(oxyalkylene) group, a poly(oxyethylene) group, a poly(oxypropylene) group, a poly(oxybutylene) group, etc. may be exemplified, and poly(oxyethylene, oxypropylene, and oxygen Ethylene block linkers) or poly(oxyethylene and oxypropylene block linkers) groups have alkylene-like units with different chain lengths within the same chain length. Furthermore, the copolymer of a monomer having a fluoroaliphatic group and (poly(oxyalkylene group)) acrylate (or methacrylate) is not only a binary copolymer, but may also have two or more different fluorine A ternary or higher copolymer obtained by copolymerizing an aliphatic group monomer or two or more different (poly(oxyalkylene)) acrylates (or methacrylates) at the same time.

For example, as a commercially available surfactant, MEGAFACE F178, F-470, F-473, F-475, F-476, F-472 (manufactured by Dainippon Ink Chemical Industry Co., Ltd.) can be mentioned. Further, the example (poly (oxyalkylene)) acrylate (or methacrylate) and a copolymer of an acrylate (or methacrylate) having C ₆ F ₁₃ group, acrylate having C ₆ F ₁₃ group Copolymer of ester (or methacrylate) and (poly(oxyethylene)) acrylate (or methacrylate) and (poly(oxypropylene)) acrylate (or methacrylate), with C ₈ F Copolymer of ₁₇ -group acrylate (or methacrylate) and (poly(oxyalkylene)) acrylate (or methacrylate), C ₈ F ₁₇ group acrylate (or methacrylate) Copolymer with (poly(oxyethylene)) acrylate (or methacrylate) and (poly(oxypropylene)) acrylate (or methacrylate), etc.

As the surfactant, a nonionic surfactant is preferred, and a fluorine-based surfactant or a silicon-based surfactant is preferred. good.

When formulating a surfactant, the blending amount is usually 0.001 to 5 mass% relative to the total mass of the organic solvent developer, preferably 0.005 to 2 mass%, and 0.01 to 0.5 mass% is more preferable .

Developer preparation method

The developer for photolithography of the present invention is in any order by combining (A) the imidazole compound represented by the general formula (1), (B) water and/or organic solvent, and (C) After various additives such as basic compounds are mixed, they can be made uniform.

≪Method for forming resist pattern≫

In the present invention, the second pattern is a method of forming a resist pattern using the above-described first developing solution for photolithography of the present invention. The method for forming a resist pattern is generally a method including the steps of: applying a photoresist composition on a substrate to form a coating film; performing a step of exposing the coating film to selective exposure; and exposing the exposed coating film The step of developing the resist pattern by dissolving the non-resistive part in the developer for photolithography of the present invention described above

To form a resist pattern. The method for forming a resist pattern of the present invention can be carried out by a conventionally well-known method in addition to using the above-mentioned first-state developer for photolithography in the step of developing. In this way, the first state-of-the-art photolithography developer of the present invention is versatile, so it can be suitably used in conventional resist pattern forming methods. Replace the previous developer.

Regardless of the negative type or the positive type, the first state photolithography developer of the present invention can be used for various resists. Specifically, examples include: a positive type resist containing a diazonaphthoquinone compound and a phenol resin; a compound containing an acid generated by exposure, a compound decomposed by acid to improve solubility in an aqueous alkali solution, and alkali solubility A chemically amplified resist of resin; a chemically amplified resist containing a compound that generates an acid by exposure and an alkali-soluble resin having a base that decomposes by acid to increase solubility in an aqueous alkali solution; Acid generating compound, crosslinking agent that starts crosslinking reaction with acid, and negative resist with alkali soluble resin; contains compound that generates acid by exposure, compound that starts superposition reaction with acid, and base Negative resistance of soluble resin, etc.

The photoresist composition, for example, uses the first-state developing solution for photolithography of the present invention (ie, so-called "negative solvent development") containing (B) an organic solvent, and is suitably used for negative solvent development The negative photoresist composition of is not particularly limited, and examples thereof include a phenol resin, polyhydroxystyrene resin, or acrylic resin as a main component.

As an example of a suitable negative resist composition, a photosensitive resin composition containing (a) a multifunctional epoxy resin, (b) a cationic polymerization initiator, and (c) a solvent can be exemplified.

(a) The multifunctional epoxy resin is not particularly limited, and can be appropriately selected from the multifunctional epoxy resins used in various applications in the past. The epoxy equivalent is preferably 1000 or less, and 500 or less. good. As a suitable example of (a) a multifunctional epoxy resin, a multifunctional phenol•phenolic epoxy Resin, multifunctional o-cresol novolac epoxy resin, multifunctional triphenyl novolac epoxy resin, multifunctional bisphenol A novolac epoxy resin, etc. Among these, polyfunctional bisphenol A novolac-type epoxy resins are preferred. (a) The functionality of the multifunctional epoxy resin is 2 or more functions, and preferably 4 or more functions.

As the (b) cationic polymerization initiator, an onium salt type cationic polymerization initiator such as an iodonium salt or an ammonium salt can be used. (c) The solvent is not particularly limited.

As the photoresist composition, a developer for photolithography according to the first aspect of the present invention containing (B) water (that is, so-called "positive development") is used as a positive type for positive development The photoresist composition is not particularly limited as long as it can be developed with an alkaline developer, and a positive photoresist composition for i, g lines, excimers such as KrF, ArF, and F ₂ can be used. The positive-type photoresist composition for laser, and furthermore, is a widely used positive-type photoresist composition such as a positive-type photoresist composition for EB (electron wire) and a positive-type photoresist for EUV. Suitable examples include: a composition containing an alkali-soluble phenol resin substituted with a quinonediazide group such as 1,2-diazonaphthoquinone sulfonamide; a compound containing a quinonediazide group and alkali-soluble Compositions of alkali-soluble resins such as phenolic resins.

Suitable photoresist compositions as chemically amplified photoresist compositions include, for example, resins (a') that reduce the solubility of organic solvent developer by the action of acid, active light or radiation The compound (b') that generates an acid and the organic solvent (c'). Such a photoresist composition is described in Patent Document 1, for example.

As the resin (a') which reduces the solubility to the organic solvent developer by the action of acid, it can be exemplified in the main chain or the side chain of the resin, or both of the main chain and the side chain, having the action by the acid A resin that decomposes and generates an alkali-soluble group (hereinafter, also referred to as "acid-decomposable group"). Examples of alkali-soluble groups include phenolic hydroxyl groups, carboxylic acid groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamides, sulfonimides, (alkylsulfonyl) (alkylcarbonyl) methylene groups, ( (Alkylsulfonyl) (alkylcarbonyl) imino, bis (alkylcarbonyl) methylene, bis (alkylcarbonyl) imino, bis (alkylsulfonyl) methylene, bis (alkyl Sulfamoyl)imino, ginseng (alkylcarbonyl)methylene, ginseng (alkylsulfonyl)methylene, etc., with carboxylic acid group, fluorinated alcohol group (preferably hexafluoroisopropyl) Alcohol) and sulfonic acid groups are preferred.

Among the acid-decomposable groups, the acid-dissociable group that is detached from the alkali-soluble group by the action of an acid can be appropriately selected as the group of the acid-dissociable group proposed by the resin for chemically amplified resists. In general, alkali-soluble groups such as carboxyl groups in (meth)acrylic acid dissociate from acetal-type acids that form cyclic or chain tertiary alkyl ester groups or alkoxyalkyl groups Sexual basis is widely known.

The compound (b') that generates an acid by irradiation with active light or radiation is not particularly limited, and various compounds conventionally used in photoresist compositions can be used. As specific examples of such a compound, a diazonium salt, a phosphonium salt, an ammonium salt, an iodonium salt, an amide imine sulfonate, an oxime sulfonate, a diazonium diazoxide, diazane, o- Nitrobenzyl sulfonate.

The photoresist composition may also contain photosensitive polyacrylic acid Compositions of photosensitive resins such as amine resins and photosensitive polybenzoxazole resins. For such a photoresist composition, the first state-of-the-art photolithography developer of the present invention may include N,N,N',N'-tetramethylurea (TMU) as a particularly suitable organic solvent. ), N,N,2-trimethylpropane amide (DMIB), etc. The developer for photolithography of the present invention as a photoresist composition for a polyamic acid containing a precursor of a photosensitive polyimide resin can be suitably used in addition to organic solvents such as TMU and DMIB. Composition of aqueous alkaline developer.

The photoresist composition containing the components described above is applied on the surface of the substrate to form a coating film on the substrate. The method of applying the photoresist composition to the substrate is not particularly limited as long as the photoresist composition is applied to the substrate with a desired film thickness. As specific examples of the coating method, a spin coating method, a spray method, a roll coating method, a dipping method, etc. may be mentioned, and the spin coating method is more preferable.

The type of substrate used in the formation of the coating film is not particularly limited, and inorganic substrates such as silicon, SiO ₂ or SiN, coated inorganic substrates such as SOG, semiconductor manufacturing steps such as ICs, liquid crystals, thermal heads, etc. can be used Circuit board manufacturing steps, and the substrates commonly used in the photolithography step of other optical applications, but in the resist pattern forming method using the first state of the invention photolithography developer solution, in particular The object to be coated can be suitably used as having a portion made of metal on the surface (such as a substrate made of metal, a substrate provided with wiring made of metal, etc.). Examples of metals that constitute substrates, wiring, and the like include gold, copper, nickel, and palladium. From the viewpoint that the purpose of the invention can be achieved particularly efficiently and from the viewpoint of high versatility, copper can be suitably used in particular.

The substrate system that supports wiring made of metal is usually an insulating substrate. Examples of insulating substrates include organic substrates, ceramic substrates, silicon substrates, and glass substrates. The material of the organic substrate is not particularly limited, and thermosetting resins such as phenol resin, urea resin, melamine resin, alkyd resin epoxy resin, or polyimide resin, polyoxyxylene resin, polyphenylene sulfide resin can be used , Aromatic polyamide resin, liquid crystal polymer and other thermoplastic resins. In addition, in a woven or non-woven fabric such as glass fiber, aromatic polyamide fiber, aromatic polyamide fiber, or the like, a material in which a thermosetting resin is impregnated and then cured can also be suitably used as a substrate.

After the photoresist composition is coated on the substrate to form a coating film, the coating film on the substrate may be heated (pre-baked) as needed. With this, a film from which the insoluble solvent has been removed can be formed uniformly. The pre-baking conditions vary according to the types of ingredients in the composition, blending ratio, coating film thickness, etc., but usually 50 ℃ ~ 160 ℃ is preferred, 60 ℃ ~ 140 ℃ is more preferred, 2 ~60 minutes or so. In addition, the film thickness of the obtained coating film is 1 to 150 μm, preferably 10 to 150 μm, still more preferably 20 to 120 μm, more preferably 20 to 75 μm.

Next, in order to form a desired pattern, the formed coating film is subjected to area selective exposure with active energy rays such as ultraviolet rays or electron rays. The exposure method is not particularly limited, and can be appropriately selected from various methods known in the past. As a suitable method, a method of irradiating the coating film with active energy rays such as ultraviolet rays or electron rays through a specified photomask.

With such exposure, an exposed portion and an unexposed portion are formed in the coating film. When the positive photoresist composition is used, the exposed portion is used as the non-resistive portion, and when the negative photoresist composition is used, the non-exposed portion is used as the non-resistive portion. The photolithography can be dissolved by contact with the developer. When a chemically amplified photoresist composition is used, the exposed portion of the coating film will be accompanied by the acid generated by the exposure, and the acid dissociable protective group of the resin will be detached, resulting in the resin Polar group, so by dissolving in the developer for photolithography of the present invention containing (B) water, a positive resist pattern can be formed; on the other hand, as for the unexposed part, due to acid dissociation of the resin The protective group is not detached, but maintains a low-polarity state, so by dissolving in the developer for photolithography of the present invention containing (B) an organic solvent, a negative resist pattern can be formed.

Examples of active energy rays include infrared light, visible light, ultraviolet light, far ultraviolet light, X-rays, and electron rays. Among them, it is generally preferable to irradiate ultraviolet light or visible light with a wavelength of 300 to 500 nm. As a light source for irradiating radiation, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halogen lamp, an argon gas laser, etc. can be used. The amount of radiation exposure varies according to the type of ingredients in the composition, the amount of formulation, the film thickness of the coating film, etc. For example, when the ultra-high pressure mercury lamp is used, it is 100~2000mJ/cm ² . When a chemically amplified photoresist composition is used, the wavelength is 250 nm or less, preferably 220 nm or less, and more preferably 1 to 200 nm, and far ultraviolet light is more preferable. As specific examples of far ultraviolet light, ArF excimer laser, F ₂ excimer laser, EUV (13 nm), etc. may be mentioned.

In the exposure step, the immersion liquid exposure method in which the optical lens part and the resist film are filled with an immersion liquid and exposed after exposure may be applied as required. The liquid immersion medium is not particularly limited as long as it has a refractive index larger than that of air and a refractive index smaller than that of the coating film used. As such a liquid immersion medium, water (pure water, deionized water), a liquid with a high refractive index prepared by mixing various additives in water, a fluorine-based inert liquid, a silicon-based inert liquid, a hydrocarbon-based liquid, etc., It is also possible to use an immersion medium with high refractive index characteristics that can be expected to be developed in the near future. Examples of the fluorine-based inert liquid include liquids containing fluorine-based compounds such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as main components. Among these, from the viewpoint of cost, safety, environmental issues, and versatility, when exposure light (ArF excimer laser, etc.) with a wavelength of 193 nm is used, water (pure water, deionized Water) is preferred. When exposure light (F ₂ excimer laser, etc.) with a wavelength of 157 nm is used, a fluorine-based inert solvent is preferred.

After exposure, baking can also be performed using well-known methods (PEB). For example, when a chemically amplified photoresist composition is used, PEB promotes the generation and diffusion of acid, and can promote the change in alkali solubility of the coating film in the exposed portion. The temperature of PEB is not particularly limited as long as a good resist pattern can be obtained, and it is usually 40°C to 160°C.

After exposure, development of the resist pattern by contacting the exposed coating film with the developer for photolithography of the present invention is carried out to dissolve unnecessary parts (non-resist parts) and remove them to obtain the designation. Of the resist pattern. The development time varies depending on the type, formulation ratio and dry film thickness of the photoresist composition, usually 1~30 minute.

The method for developing the resist pattern with the developing solution for photolithography is not particularly limited, and can be appropriately selected and implemented by a well-known development method. As a suitable developing method, for example, a method of immersing a substrate provided with an exposed coating film for a fixed time in a developing solution for photolithography (immersion method); by using surface tension, a developing solution for photolithography A method of stacking onto the surface of the exposed coating film and standing still for a fixed time (mixing method); a method of spraying a developing solution for photolithography toward the surface of the exposed coating film (spray method); for rotating at a fixed speed The method of scanning the developing solution for photolithography toward the exposed coating film at a fixed speed and discharging the nozzle while continuously discharging the developing solution for photolithography (dynamic dispensing method) and the like.

In addition, after the development step, a step of stopping development while replacing the developing solution for photolithography with another solvent may be performed.

After the development, a wetting step using a wetting liquid to wash the resist pattern can also be performed. The wetting liquid is not particularly limited as long as it does not dissolve the resist pattern. For the developer of the first state of the invention for photolithography, when (B) water is used, water can be used, when (B ) In the case of an organic solvent, a solution containing a general organic solvent can be used. Examples of the organic solvent that can be used as a wetting liquid include the same organic solvents that can be included in the developer for photolithography. The wetting liquid may contain a plurality of the above organic solvents, and may contain organic solvents other than the above.

It is also possible to add a suitable amount of surfactant to the wetting liquid and use it.

After development, or after wetting, use a well-known method such as an air gun or an oven to adapt the base with the resist pattern The board is preferably dried.

The resist pattern forming method of the present invention is developed by using the first state photolithography developer of the present invention, pre-baked or PEB, especially by PEB, even if it is made of metal by heating In the case of such a substrate or wiring, for such a substrate or wiring, it can suppress the infiltration of the resist pattern by the dendritic crystals of the metal compound generated by migration, or inhibit the oxidation or oxidation of the metal surface of the substrate or wiring Layer formation. In this regard, the developer for photolithography of the present invention makes it possible to protect, in particular, prevent corrosion of substrates, wiring, and the like made of metal.

[Example]

Hereinafter, the present invention will be further described in detail through examples, but the present invention is not limited to these examples.

[Examples, Comparative Examples]

<imidazole compound>

Compound 1 of the following structure, Comparative Compound 1 and Comparative Compound 2 were used.

[Synthesis Example 1]

Among the aforementioned imidazole compounds, the aforementioned compound 1 was synthesized by the following method.

First, 30 g of a cinnamic acid derivative having the structure shown in the following formula was dissolved in 200 g of methanol, and then 7 g of potassium hydroxide was added to the methanol. Next, the methanol solution was stirred at 40°C. Methanol was distilled off, and the residue was suspended in 200 g of water. In the obtained suspension, 200 g of tetrahydrofuran was mixed and stirred, and the aqueous phase was separated. Under ice cooling, after adding and stirring 4 g of hydrochloric acid, 100 g of ethyl acetate was mixed and stirred. After standing the mixed liquid, the oil phase was separated. The target substance is crystallized from the oil phase, and the precipitate is recovered to obtain the imidazole compound (compound 1) having the above structure.

The ¹ H-NMR measurement results of the imidazole compound (Compound 1) having the above structure are as follows.

¹ H-NMR (DMSO): 11.724 (s, 1H), 7.838 (s, 1H), 7.340 (d, 2H, J=4.3 Hz), 7.321 (d, 1H, J=7.2 Hz), 6.893 (d, 2H, J=4.3Hz), 6.876(d, 1H, J=6.1Hz), 5.695(dd, 1H, J=4.3J, 3.2J), 3.720(s, 3H), 3.250(m, 2H)

[Example of preparation of developer]

As shown in Table 1, an alkali developing solution containing an imidazole compound was prepared. As a solvent for the alkaline developer, as shown in Table 1, a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH), a 0.04% aqueous solution of potassium hydroxide (KOH), and a 0.1% aqueous solution of sodium hydroxide (NaOH) can be used As a solvent for organic solvent development, propylene glycol monomethyl ether acetate (PGMEA) can be used. Table 1 shows the unit of the numerical value of the content of each component, which is mass %.

[Formation of resist pattern]

By a prescribed method, a photoresist composition was coated on a copper substrate to form a coating film with a thickness of 1 μm, and then exposed. As the photoresist composition, three types of resist compositions (OFPR, PMER P, TMMR; all are manufactured by Tokyo Application Chemical Industry Co., Ltd.).

Using each developer obtained by the above-mentioned preparation example, the exposed coating film was developed. After the development, the substrate was baked at 230°C for 20 minutes to form a resist pattern of a specified pattern.

After post-baking, use a scanning electron microscope to observe the cross section of the substrate and observe the formation of the oxide layer. When the oxide layer is formed, the interface between the substrate and the oxide layer can be clearly observed on the cross section of the substrate. From the scanning electron microscope image, the film thickness of the formed oxide layer can be determined, and the formation and migration of the oxide layer can be evaluated based on the following criteria. Record the results in Table 1.

<Evaluation criteria>

◎: No formation or migration of oxide layer occurs.

○: There is formation or migration of an oxide layer with a film thickness less than 50 nm.

×: There is formation or migration of an oxide layer with a film thickness of 50 nm or more.

It can be seen from Table 1 that when the developer for photolithography containing Compound 1 is used for development, even if the copper substrate is heated by post-development baking (PEB), it can be suppressed in the copper substrate. Oxide layer formation and migration.

Claims (5)

A developer for photolithography, which comprises (A) an imidazole compound represented by the following general formula (1), and (B) water and/or an organic solvent,

(In the formula, R ¹ is a hydrogen atom or an alkyl group, R ² is an aromatic group which may have a substituent, R ³ is an alkylene group which may have a substituent, and R ⁴ is independently a halogen atom, a hydroxyl group, a mercapto group, Thioether group, silane group, silanol group, nitro group, nitroso group, sulfonate group, phosphine group, phosphine oxide group, phosphonate group, or organic group, n is an integer of 0~3). The developer for photolithography according to claim 1, which further contains (C) a basic compound. The developer for photolithography according to claim 2, wherein the basic compound (C) is at least one selected from the group consisting of inorganic bases, amine compounds, and fourth-order ammonium salts. The developer for photolithography according to any one of claims 1 to 3, wherein the organic solvent (B) is selected from the group consisting of ketone-based solvents, ester-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and At least one species of hydrocarbon-based solvents. A method for forming a resist pattern, which uses the photolithography developer according to any one of claims 1 to 4.