JP6415374B2 - Photolithographic developer and resist pattern forming method - Google Patents

Description

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

  In response to demands for miniaturization and high performance of various electronic devices, miniaturization and high integration of printed wiring boards and various electric / electronic elements are progressing. For this reason, in printed wiring boards and electrical / electronic elements, metal wiring is becoming thinner and the spacing between wirings is becoming narrower. Such printed wiring boards and various electric / electronic elements are excellent in conductivity and workability. For example, copper, silver, tin, lead, zinc, aluminum, nickel, gold, and these are used as materials for the board and wiring. Metals such as these alloys are widely used.

  When processing printed wiring boards and electrical / electronic elements into various devices, metal substrates and wiring are developed when, for example, surface mounting or resist patterns are formed on a circuit using a photosensitive composition or the like. Often heated for later curing. There are the following problems in heating a metal substrate and wiring.

  First, there is a problem that the surface of the substrate or wiring is oxidized by heating. Since resistance values differ greatly between metal and metal oxide, if the surface of a thin circuit is oxidized, the electrical resistance of the circuit tends to vary. Variations in the electrical resistance of the circuit greatly affect product performance. Further, when the circuit surface is oxidized, the wettability between the circuit surface and the solder deteriorates, and soldering on the circuit is difficult.

  In addition, when a substrate or wiring made of metal is heated, dendritic crystals made of a metal compound are likely to be formed on the surface of the substrate or wiring due to elution (migration) of metal ions on the surface of the substrate by moisture on the surface of the substrate or the like. . In the case where the distance between the wirings is narrow, there is a problem that the wiring is likely to be short-circuited due to generation of a dendritic crystal of a metal compound caused by migration.

  In order to solve the above problem, a method of surface-treating a metal before heating has been proposed. Specifically, a method of surface-treating a 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 (Patent Document 1), an azole compound There has been proposed a method (Patent Document 2) for surface-treating a wiring made of copper or an alloy containing copper using an aqueous solution of the above.

JP 2014-101554 A JP 2012-244005 A

  However, even with the treatment with the surface treatment liquid as described in Patent Documents 1 and 2, migration and wiring surface oxidation may not be satisfactorily suppressed depending on the temperature at which the wiring is heated and the number of times of heating. It is also desirable if the effect of inhibiting migration and wiring surface oxidation can be brought about by the developer used before the resist pattern is cured.

  The present invention has been made in view of the above problems, and provides a developer for photolithography excellent in the effect of suppressing migration or oxidation of the surface of a substrate or wiring, and uses the developer for photolithography. An object of the present invention is to provide a resist pattern forming method.

  The present inventors include a saturated fatty acid or a saturated fatty acid ester having a specific structure in which a predetermined position is substituted with an aromatic group having a predetermined structure and an imidazolyl group which may have a substituent. It has been found that the above-mentioned problems can be solved by developing a photosensitive resin composition layer formed on a metal substrate or wiring using a developer for photolithography, and the present invention has been completed. Specifically, the present invention provides the following.

（式中、Ｒ^１は水素原子又はアルキル基であり、Ｒ^２は置換基を有してもよい芳香族基であり、Ｒ^３は置換基を有してもよいアルキレン基であり、Ｒ^４は、それぞれ独立にハロゲン原子、水酸基、メルカプト基、スルフィド基、シリル基、シラノール基、ニトロ基、ニトロソ基、スルホナト基、ホスフィノ基、ホスフィニル基、ホスホナト基、又は有機基であり、ｎは０〜３の整数である。） A first aspect of the present invention is a photolithography developer containing an imidazole compound represented by the following 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 that may have a substituent, R ³ is an alkylene group that may have a substituent, and R ⁴ Are each independently a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfonate group, a phosphino group, a phosphinyl group, a phosphonate group, or an organic group. It is an integer of 3.)

  The second aspect of the present invention is a resist pattern forming method using the photolithography developer according to the first aspect of the present invention.

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

≪Developer for photolithography≫
The developer for photolithography of the present invention contains (A) an imidazole compound represented by the following formula (1) and (B) water and / or an organic solvent.

(A) Imidazole compound represented by the formula (1) When the imidazole compound represented by the formula (1) (hereinafter sometimes abbreviated as “imidazole compound”) is contacted with a metal, the formula (1) The represented imidazole compound reacts with metal ions to form a chemical conversion film on the surface of the metal. When a chemical conversion film is formed on the surface of a wiring made of metal, a short circuit between wirings due to metal migration and oxidation of the metal are suppressed.

（式（１）中、Ｒ^１は水素原子又はアルキル基であり、Ｒ^２は置換基を有してもよい芳香族基であり、Ｒ^３は置換基を有してもよいアルキレン基であり、Ｒ^４は、ハロゲン原子、水酸基、メルカプト基、スルフィド基、シリル基、シラノール基、ニトロ基、ニトロソ基、スルホナト基、ホスフィノ基、ホスフィニル基、ホスホナト基、又は有機基であり、ｎは０〜３の整数である。）

(In Formula (1), R ¹ is a hydrogen atom or an alkyl group, R ² is an aromatic group that may have a substituent, and R ³ is an alkylene group that may have a substituent. , R ⁴ is a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfonate group, a phosphino group, a phosphinyl group, a phosphonate group, or an organic group, and n is 0 to 0 It is an integer of 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 linear alkyl group or a branched alkyl group. Although the carbon atom number of the said alkyl group is not specifically limited, 1-20 are preferable, 1-10 are preferable and 1-5 are more preferable.

Specific examples of the alkyl group suitable as R ¹ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, Isopentyl group, tert-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethyl-n-hexyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group Group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, and n-icosyl group.

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

  The type of the aromatic hydrocarbon group is not particularly limited as long as the object of the present invention is not impaired. The aromatic hydrocarbon group may be a monocyclic aromatic group, may be formed by condensation of two or more aromatic hydrocarbon groups, and may be two or more aromatic hydrocarbon groups. May be formed by a single bond. As the aromatic hydrocarbon group, a phenyl group, a naphthyl group, a biphenylyl group, an anthryl group, and a phenanthrenyl group are preferable.

  The kind of the aromatic heterocyclic group is not particularly limited as long as the object of the present invention is not impaired. The aromatic heterocyclic group may be a monocyclic group or a polycyclic group. As the aromatic heterocyclic group, a pyridyl group, a furyl group, a thienyl group, an imidazolyl group, a pyrazolyl group, an oxazolyl group, a thiazolyl group, an isoxazolyl group, an isothiazolyl group, a benzoxazolyl group, a benzothiazolyl group, and a benzoimidazolyl group are preferable.

  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 sulfide group, a silyl group, a silanol group, a nitro group, and a nitroso group. , Sulfino group, sulfo group, sulfonate group, phosphino group, phosphinyl group, phosphono group, phosphonate group, amino group, ammonio group, and organic group. When a phenyl group, a polycyclic aromatic hydrocarbon group, or an aromatic heterocyclic group has a plurality of substituents, the plurality of substituents may be the same or different.

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

  When the aromatic group has a substituent on the adjacent carbon atom, the two substituents bonded on the adjacent carbon atom may combine to form a cyclic structure. Examples of the cyclic structure include an aliphatic hydrocarbon ring and an aliphatic ring containing a hetero atom.

  When the substituent that the aromatic group has is an organic group, the bond contained in the organic group is not particularly limited as long as the effect of the present invention is not impaired, and the organic group includes an oxygen atom, a nitrogen atom, a silicon atom, and the like. A bond containing a hetero atom may be included. Specific examples of the bond containing a hetero atom include an ether bond, a thioether bond, a carbonyl bond, a thiocarbonyl bond, an ester bond, an amide bond, a urethane bond, and an imino bond (—N═C (—R) —, —C (= NR)-: R represents a hydrogen atom or an organic group), carbonate bond, sulfonyl bond, sulfinyl bond, azo bond and the like.

  As the bond containing a hetero atom which the organic group may have, from the viewpoint of heat resistance of the imidazole compound represented by the formula (1), an ether bond, a thioether bond, a carbonyl bond, a thiocarbonyl bond, an ester bond, an amide Bond, amino bond (—NR—: R represents a hydrogen atom or a monovalent organic group) urethane bond, imino bond (—N═C (—R) —, —C (═NR) —: R represents a hydrogen atom Or a monovalent organic group), a carbonate bond, a sulfonyl bond, or a sulfinyl bond.

  When the organic group is a substituent other than a hydrocarbon group, the type of 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 substituents other than hydrocarbon groups include halogen atoms, hydroxyl groups, mercapto groups, sulfide groups, cyano groups, isocyano groups, cyanato groups, isocyanato groups, thiocyanato groups, isothiocyanato groups, silyl groups, silanol groups, alkoxy groups. , Alkoxycarbonyl group, amino group, monoalkylamino group, dialkylaluminum group, monoarylamino group, diarylamino group, carbamoyl group, thiocarbamoyl group, nitro group, nitroso group, carboxylate group, acyl group, acyloxy group, sulfino Group, sulfonate group, phosphino group, phosphinyl group, phosphonate group, alkyl ether group, alkenyl ether group, alkyl thioether group, alkenyl thioether group, aryl ether group, aryl thioether group and the like. The hydrogen atom contained in the substituent may be substituted with a hydrocarbon group. Further, the hydrocarbon group contained in the substituent may be linear, branched, or cyclic.

  Examples of the substituent that the phenyl group, the polycyclic aromatic hydrocarbon group, or the aromatic heterocyclic group has include an alkyl group having 1 to 12 carbon atoms, an aryl group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Are preferably an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 1 to 12 carbon atoms, an arylamino group having 1 to 12 carbon atoms, and a halogen atom.

As R ² , the imidazole compound represented by the formula (1) can be synthesized inexpensively and easily, and the solubility of the imidazole compound in water or an organic solvent is good. Group, furyl group and thienyl group are 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 amino group, a cyano group, and a halogen atom. The alkylene group may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferred. Although the carbon atom number of an alkylene group is not specifically limited, 1-20 are preferable, 1-10 are preferable and 1-5 are more preferable. The number of carbon atoms of the alkylene group does not include the carbon atom of the substituent that is bonded to the alkylene group.

  The alkoxy group as a substituent bonded to the alkylene group may be a linear alkoxy group or a branched alkoxy group. Although the carbon atom number of the alkoxy group as a substituent is not specifically limited, 1-10 are preferable, 1-6 are more preferable, and 1-3 are especially preferable.

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

Specific examples of the alkylene group suitable as R ³ include methylene group, ethane-1,2-diyl group, n-propane-1,3-diyl group, n-propane-2,2-diyl group, and n-butane. -1,4-diyl group, n-pentane-1,5-diyl group, n-hexane-1,6-diyl group, n-heptane-1,7-diyl group, n-octane-1,8-diyl Group, n-nonane-1,9-diyl group, n-decane-1,10-diyl group, n-undecane-1,11-diyl group, n-dodecane-1,12-diyl group, n-tridecane- 1,13-diyl group, n-tetradecane-1,14-diyl group, n-pentadecane-1,15-diyl group, n-hexadecane-1,16-diyl group, n-heptadecane-1,17-diyl group N-octadecane-1,18-diyl group, n -Nonadecane-1,19-diyl group and n-icosane-1,20-diyl group are mentioned.

R ⁴ is a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfonate group, a phosphino group, a phosphinyl group, a phosphonate group, or an organic group, and n is 0 to 3 Is an integer. When n is an integer of 2 to 3, the 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 that the aromatic group may have as a substituent for R ² .

When R ⁴ is an organic group, the organic group is preferably an alkyl group, an aromatic hydrocarbon group, or an aromatic heterocyclic group. As the alkyl group, a linear or branched alkyl group having 1 to 8 carbon atoms is preferable, and a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are more preferable. As the aromatic hydrocarbon group, a phenyl group, a naphthyl group, a biphenylyl group, an anthryl group, and a phenanthrenyl group are preferable, a phenyl group and a naphthyl group are more preferable, and a phenyl group is particularly preferable. As the aromatic heterocyclic group, a pyridyl group, a furyl group, a thienyl group, an imidazolyl group, a pyrazolyl group, an oxazolyl group, a thiazolyl group, an isoxazolyl group, an isothiazolyl group, a benzoxazolyl group, a benzothiazolyl group, and a benzoimidazolyl group are preferable. A furyl group and a thienyl group are more preferable.

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 or an aromatic heterocyclic group, the bonding position of these groups on imidazole is preferably the 2-position.

Among the imidazole compounds represented by the above formula (1), the compounds represented by the following formula (1-1) are preferable because they can be synthesized inexpensively and easily and have excellent solubility in water and organic solvents. And a compound represented by formula (1-1), wherein R ³ is a methylene group is more preferable.

（式（１−１）中、Ｒ^１、Ｒ^３、Ｒ^４、及びｎは、式（１）と同様であり、Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^８、及びＲ^９は、それぞれ独立に、水素原子、ハロゲン原子、水酸基、メルカプト基、スルフィド基、シリル基、シラノール基、ニトロ基、ニトロソ基、スルフィノ基、スルホ基、スルホナト基、ホスフィノ基、ホスフィニル基、ホスホノ基、ホスホナト基、アミノ基、アンモニオ基、又は有機基であり、ただし、Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^８、及びＲ^９のうち少なくとも１つは水素原子以外の基である。）

(In Formula (1-1), R ¹ , R ³ , R ⁴ , and n are the same as in Formula (1), and R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ are each independently selected. Hydrogen atom, halogen atom, hydroxyl group, mercapto group, sulfide group, silyl group, silanol group, nitro group, nitroso group, sulfino group, sulfo group, sulfonate group, phosphino group, phosphinyl group, phosphono group, phosphonate group, amino group A group, an ammonio group, or an organic group, provided that 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 that R ² in Formula (1) has as a substituent. R ⁵ , R ⁶ , R ⁷ and R ⁸ are preferably a hydrogen atom from the viewpoint of solubility of the imidazole compound in a solvent.

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 the following substituent, R ⁵ , R ⁶ , R ⁷ and R ⁸ are preferably hydrogen atoms.
-O-R 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, 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.

（式（１−１−１）において、Ｒ^１、Ｒ^４、及びｎは、式（１）と同様であり、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、及びＲ^１５は、それぞれ独立に、水素原子、水酸基、メルカプト基、スルフィド基、シリル基、シラノール基、ニトロ基、ニトロソ基、スルフィノ基、スルホ基、スルホナト基、ホスフィノ基、ホスフィニル基、ホスホノ基、ホスホナト基、アミノ基、アンモニオ基、又は有機基であり、ただし、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、及びＲ^１５のうち少なくとも１つは水素原子以外の基である。） Among the compounds represented by the formula (1-1), a compound represented by the following formula (1-1-1) is preferable.

(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 each independently , Hydrogen atom, hydroxyl group, mercapto group, sulfide group, silyl group, silanol group, nitro group, nitroso group, sulfino group, sulfo group, sulfonate group, phosphino group, phosphinyl group, phosphono group, phosphonato group, amino group, ammonio group Or an organic group, provided that 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 formula (1-1-1), at least one of R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ is a group represented by the aforementioned —O—R ^10. It is preferable that R ¹⁵ is a group represented by —O—R ¹⁰ . When R ¹⁵ is a group represented by —O—R 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, the halogen-containing carboxylic acid derivative represented by the following formula (I) and the imidazole compound represented by the following formula (II) are reacted according to a conventional method to perform imidazolylation, whereby the above formula (1) The imidazole compound represented by can be synthesized.

（式（Ｉ）及び式（ＩＩ）中、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４及びｎは、式（１）と同様である。式（Ｉ）において、Ｈａｌはハロゲン原子である。）

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

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), The imidazole compound can also be synthesized by the method using the Michael addition reaction described.

（式（１−２）中、Ｒ^１、Ｒ^２、Ｒ^４及びｎは、式（１）と同様である。）

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

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

（式（ＩＩＩ）中、Ｒ^１、Ｒ^２、Ｒ^４及びｎは、式（１）と同様である。）

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

  Moreover, the imidazole compound represented by a following formula (1-3) is obtained by adding the 3-substituted acrylic acid derivative containing the imidazolyl group represented by the following formula (IV) in the solvent containing water. .

（式（ＩＶ）及び式（１−３）中、Ｒ^２、Ｒ^４及びｎは、式（１）と同様である。）

(In formula (IV) and formula (1-3), R ² , R ⁴ and n are the same as in 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) And generate. 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), and is represented by the above formula (1-3). An imidazole compound is formed.

（式（Ｖ）中、Ｒ^２は、式（１）と同様である。）

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

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

(B) Water and / or Organic Solvent 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 solvent〕
When performing negative development in a photolithography system where the exposed area is insoluble in an organic solvent, or when performing positive development in a photolithography system where the unexposed area is insoluble in an organic solvent An organic developer containing an organic solvent can be used as the liquid.
As an organic developing solution that can be used for solvent development, polar solvents such as ketone solvents, alcohol solvents, amide solvents, ether solvents, ester solvents, and hydrocarbon solvents can be used.

  In the present invention, the ketone solvent is a solvent having a ketone group in the molecule, the ester solvent is a solvent having an ester group in the molecule, and the alcohol solvent is alcoholic in the molecule. It is a solvent having a hydroxyl group, an amide solvent is a solvent having an amide group in the molecule, and an ether solvent is a solvent having an ether bond in the molecule. Among these, there is a solvent having a plurality of types of the above functional groups in one molecule. In that case, it corresponds to any solvent type including the functional group of the solvent. For example, diethylene glycol monomethyl ether corresponds to both alcohol solvents and ether solvents in the above classification. Further, the hydrocarbon solvent is a hydrocarbon solvent having no substituent.

  Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methyl amyl ketone), 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, Examples include cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, acetonylacetone, ionone, diacetylalcohol, acetylcarbinol, acetophenone, methylnaphthylketone, isophorone, propylene carbonate, γ-butyrolactone, etc. it can.

  Examples of the ester solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl. Ether acetate, propylene glycol monopropyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monopheny Ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 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, 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, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropio And ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, and γ-butyrolactone.

  Examples of the alcohol solvent include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, n-heptyl alcohol, Alcohols such as n-octyl alcohol, n-decanol, 4-methyl-2-pentanol (MIBC: methyl isobutyl carbinol), 3-methoxy-1-butanol, and glycols such as ethylene glycol, diethylene glycol and triethylene glycol Solvents, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether Contains hydroxyl groups such as 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 Examples include glycol ether solvents. Among these, it is preferable to use a glycol ether solvent.

  Examples of the ether solvent include a hydroxyl group such as dibutyl ether, ethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol dibutyl ether in addition to the above-described glycol ether solvent containing the hydroxyl group. Glycol ether solvents that do not contain diisopentyl ether, diisobutyl ether, dioxane, tetrahydrofuran, anisole, perfluoro-2-butyltetrahydrofuran, perfluorotetrahydrofuran, 1,4-dioxane and the like. Preferably, a glycol ether solvent is used.

  Examples of the amide solvent include dimethyl sulfoxide, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolide. Non etc. can be used.

Examples of hydrocarbon solvents include fats such as pentane, hexane, octane, decane, 2,2,4-trimethylpentane, 2,2,3-trimethylhexane, perfluorohexane, perfluoroheptane, limonene, and pinene. Group hydrocarbon solvents, toluene, xylene, ethylbenzene, propylbenzene, 1-methylpropylbenzene, 2-methylpropylbenzene, dimethylbenzene, diethylbenzene, ethylmethylbenzene, trimethylbenzene, 1,2,4-trimethylbenzene, ethyldimethyl Aromatic hydrocarbon solvents such as benzene and dipropylbenzene are listed.
A plurality of the above solvents may be mixed, or may be used by mixing with a solvent other than those described above or water.

  Among these, ester solvents are preferable. As the ester solvent, a solvent represented by general formula (4) described later or a solvent represented by general formula (5) described later is preferably used, and a solvent represented by general formula (5) is used. Is more preferable.

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

In general formula (4),
R ^S1 and R ^S2 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxyl group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group, or a halogen atom. R ^S1 and R ^S2 may combine with each other to form a ring. R ^S1 and R ^S2 are preferably a hydrogen atom or an alkyl group, and the alkyl group of R ^S1 and R ^S2 may be substituted with a hydroxyl group, a carbonyl group, a cyano group, or the like.

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

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

  The solvent represented by the general formula (4) 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 can be mixed without being separated into the solvent represented by the general formula (4), and the solvents represented by the general formula (4) may be used in combination. The solvent represented by the general formula (4) may be used by mixing with a solvent selected from other ester solvents, ketone solvents, alcohol solvents, amide solvents, ether solvents and hydrocarbon solvents. Good. One or more solvents can be used in combination, but it is preferable to use one solvent in order to obtain stable performance. The mixing ratio of the solvent represented by the general formula (4) and the combined solvent when the combined solvent is used is usually 20:80 to 99: 1, preferably 50:50 to 97: 3. Preferably it is 60: 40-95: 5, Most preferably, it is 60: 40-90: 10.

  As a developer that can be used for solvent development, a solvent represented by the following general formula (5) is preferably used.

In general formula (5),
R ^S3 and R ^S5 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxyl group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group, or a halogen atom. R ^S3 and R ^S5 may be bonded to each other to form a ring.
R ^S3 and R ^S5 are preferably a hydrogen atom or an alkyl group.
R ^S4 represents an alkylene group or a cycloalkylene group. R ^S4 is preferably a hydrogen atom or an alkyl group.
The alkyl group possessed by R ^S3 , R ^S4 and R ^S5 may be substituted with a hydroxyl group, a carbonyl group, a cyano group or the like.

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

  Examples of the solvent represented by the general formula (5) include ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl. Ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methyl-3-methoxy Lopionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, ethyl methoxyacetate, ethyl ethoxyacetate, 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-methoxy pentyl acetate, and the like.

Among these, as for the solvent represented by General formula (5), it is preferable that R ^S2 , R ^S4 and R ^S5 are unsubstituted alkyl groups, and propylene glycol monomethyl ether acetate (PGMEA) is particularly preferable.

  The solvent represented by the 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 can be mixed without being separated into the solvent represented by the general formula (5), and the solvents represented by the general formula (5) may be used in combination. The solvent represented by the general formula (5) may be used by mixing with a solvent selected from other ester solvents, ketone solvents, alcohol solvents, amide solvents, ether solvents and hydrocarbon solvents. Good. One or more solvents can be used in combination, but it is preferable to use one solvent in order to obtain stable performance. When mixing and using 1 type of combined use solvent, the mixing ratio of the solvent represented by General formula (5) and a combined use solvent is 20: 80-99: 1 normally, Preferably it is 50: 50-97: 3, Preferably it is 60: 40-95: 5, Most preferably, it is 60: 40-90: 10.

（式（６）中、Ｒ^Ｓ６及びＲ^Ｓ７は、それぞれ独立に炭素原子数１〜３のアルキル基であり、Ｒ^Ｓ８は下式（６−１）又は下式（６−２）：

で表される基である。式（６−１）中、Ｒ^Ｓ９は、水素原子又は水酸基であり、Ｒ^Ｓ１０及びＲ^Ｓ１１は、それぞれ独立に炭素原子数１〜３のアルキル基である。式（６−２）中、Ｒ^Ｓ１２及びＲ^Ｓ１３は、それぞれ独立に水素原子、又は炭素原子数１〜３のアルキル基である。） Moreover, it is preferable to use the solvent which consists of a compound (S) represented by following General formula (6) as a developing solution which can be used when performing solvent image development.

(In formula (6), R ^S6 and R ^S7 are each independently an alkyl group having 1 to 3 carbon atoms, and R ^S8 represents the following formula (6-1) or the following formula (6-2):

It is group represented by these. 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 each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. )

Specific examples of the compound (S) represented by the formula (6) when R ^S8 is a group represented by the formula (6-1) include N, N, 2-trimethylpropionamide, N— Ethyl, N, 2-dimethylpropionamide, N, N-diethyl-2-methylpropionamide, N, N, 2-trimethyl-2-hydroxypropionamide, N-ethyl-N, 2-dimethyl-2-hydroxypropion Amides, N, N-diethyl-2-hydroxy-2-methylpropionamide and the like.

Specific examples of the compound (S) represented by formula (6) when R ^S8 is a group represented by formula (6-2) include N, N, N ′, N′-tetramethyl. Urea, N, N, N ′, N′-tetraethylurea and the like can be mentioned.

  Among the examples of the compound (S), N, N, 2-trimethylpropionamide (DMIB) and N, N, N ′, N′-tetramethylurea (TMU) are particularly preferable.

  The solvent composed of the compound (S) represented by the general formula (6) 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 can be mixed without being separated into the solvent represented by the general formula (6), and the solvents represented by the general formula (6) may be used in combination. The solvent represented by the general formula (6) may be used by mixing with a solvent selected from other ester solvents, ketone solvents, alcohol solvents, amide solvents, ether solvents and hydrocarbon solvents. Good. One or more solvents can be used in combination, but it is preferable to use one solvent in order to obtain stable performance. The mixing ratio of the solvent represented by the general formula (6) and the combined solvent when the combined solvent is used is usually 20:80 to 99: 1, preferably 50:50 to 97: 3. Preferably it is 60: 40-95: 5, Most preferably, it is 60: 40-90: 10.

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

  As the solvent used in the solvent development, an organic solvent containing no halogen atom is preferably used from the viewpoint of cost reduction of the solvent used for the development. The content of the organic solvent not containing a halogen atom in the total weight of all the solvents used in the solvent development is usually 60% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, particularly Preferably it is 97 mass% or more.

The boiling point of the solvent used in the solvent development is desirably 50 ° C. or higher and lower than 250 ° C.
The ignition point of the solvent used for solvent development is preferably 200 ° C. or higher.

〔water〕
(B) Water and / or an organic solvent contained in the developer for photolithography of the present invention is preferably water, and may be a mixture of water and an organic solvent. It is more preferable to use The developer for photolithography of the present invention, when water is used, particularly when only water is used as a solvent, usually contains the following (C) basic compound, and also contains (C) the basic compound. By doing so, it can be used as an alkali developer. Such an alkaline developer is used in negative development in a photolithography system in which an exposed portion is insoluble in an alkaline developer, or in a photolithography system in which an unexposed portion is insoluble in an alkaline developer. It can be suitably used when developing.

(C) Basic compound The developer for photolithography of the present invention comprises (A) an imidazole compound represented by the above formula (1) and (B) water and / or an organic solvent, and (C) a base. It may contain an ionic compound. When the developer for photolithography of the present invention contains (C) a basic compound, it can usually be used as an alkali developer, and water is preferably used as the above-mentioned (B) water and / or organic solvent. .
(C) A conventionally well-known basic compound can be used as a basic compound. Examples of such a basic compound include a basic compound containing an alkali metal and an organic base containing no metal ion.

  Examples of basic compounds containing alkali metals include hydroxides, carbonates, bicarbonates, phosphates, pyrophosphates of alkali metals such as lithium, sodium, and potassium. Specifically, sodium hydroxide And inorganic alkalis such as potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia.

  Examples of organic bases not containing metal ions include primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-butylamine; tertiary amines such as triethylamine and methyldiethylamine; Methylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide (TBAH), trimethyl (2-hydroxyethyl) ammonium hydroxide, triethyl (2-hydroxyethyl) ammonium hydroxide, Quaternary ammonium salts such as tripropyl (2-hydroxyethyl) ammonium hydroxide, trimethyl (1-hydroxypropyl) ammonium hydroxide; dimethylethanolamine; Alcohol amines such as triethanolamine; and the like. In addition, amines containing linear, branched or cyclic primary, secondary and tertiary amines, specifically diaminoalkanes such as 1,3-diaminopropane, 4,4 Examples also include arylamines such as' -diaminodiphenylamine, alkylamines such as N, N'-diaminodialkylamine, and the like. Further, a heterocyclic base having 3 to 5 carbon atoms and 1 or 2 heteroatoms selected from nitrogen, oxygen and sulfur in the ring skeleton, specifically pyrrole, pyridine, pyrazine, pyrrolidine, Examples include piperidine, pyrrolidone, morpholine, oxazole and thiazole, and cyclic amines such as pyrrole and piperidine are preferred. Among these organic bases, quaternary ammonium compounds, particularly tetramethylammonium hydroxide (TMAH) is preferable. These organic bases may be used alone or in combination of two or more.

Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline aqueous solution.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.
In particular, a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH) is desirable.

Other Components Known additives can be added to the organic solvent developer as necessary. Examples of the additive include a surfactant. The surfactant is not particularly limited. 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. Examples of such an anionic surfactant include a surfactant having a carboxylic acid group, a sulfonic acid group, or a phosphoric acid group as an anionic group.

  Specifically, higher fatty acids having an alkyl group having 8 to 20 carbon atoms, higher alkyl sulfates, higher alkyl sulfonic acids, higher alkyl aryl sulfonic acids, other surfactants having sulfonic acid groups, or higher alcohol phosphoric acids Examples thereof include esters or salts thereof. Here, the alkyl group possessed by the anionic surfactant may be either linear or branched, and a phenylene group or an oxygen atom may be interposed in the branched chain. Some of the hydrogen atoms may be substituted with a hydroxyl group or a carboxyl group.

  Specific examples of the higher fatty acid include dodecanoic acid, tetradecanoic acid and stearic acid. Specific examples of the higher alkyl sulfate include decyl sulfate and dodecyl sulfate. Examples of the higher alkyl sulfonic acid include decane sulfonic acid, dodecane sulfonic acid, tetradecane sulfonic acid, pentadecane sulfonic acid, and stearic acid sulfonic acid.

  Specific examples of higher alkylaryl sulfonic acids include dodecylbenzene sulfonic acid and decylnaphthalene sulfonic acid.

  Furthermore, examples of other surfactants having a sulfonic acid group include alkyl diphenyl ether disulfonic acids such as dodecyl diphenyl ether disulfonic acid, and dialkyl sulfosuccinates such as dioctyl sulfosuccinate.

  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. Specifically, alkylsulfonic acid, alkylbenzenesulfonic acid, olefinsulfonic acid, alkyldiphenylethersulfonic acid, alkylnaphthalenesulfonic acid. And dialkylsulfosuccinate. 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 alkyl sulfonic acid is preferably 9 to 21, and more preferably 12 to 18. Moreover, it is preferable that it is 6-18, and, as for the average carbon number of the alkyl group of alkylbenzenesulfonic acid, it is more preferable that it is 9-15. The average carbon number of the alkyl group of the alkyldiphenyl ether disulfonic acid is preferably 6-18, and more preferably 9-15. Furthermore, 4-12 are preferable and, as for the average carbon number of the alkyl group of dialkyl sulfosuccinate, 6-10 are more preferable.

  Examples of nonionic surfactants include polyoxyethylene alkyl ethers and acetylenic nonionic surfactants. As the nonionic surfactant, those having water solubility are desirable. The range of HLB7-17 is good. When HLB is small and water solubility is insufficient, it may be made water-soluble by mixing with other active agents.

  Examples of commercially available surfactants that can be used include F-top EF301 and EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430 and 431 (manufactured by Sumitomo 3M Ltd.), MegaFuck F171, F173, F176, F189, and R08. (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical Co., Ltd.), etc. Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon surfactant.

  In addition to the above-mentioned known surfactants, surfactants include fluoro derivatives derived from fluoro aliphatic compounds produced by the telomerization method (also referred to as telomer method) or the oligomerization method (also referred to as oligomer method). A surfactant using a polymer having an aliphatic group can be used.

  As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain length alkylenes in the same chain length, such as a block linked body) or a poly (block linked body of oxyethylene and oxypropylene) groups, may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

For example, Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.) are mentioned as commercially available surfactants. Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy Copolymer) of (ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate), acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate having C ₈ F ₁₇ groups (or Copolymer of acrylate (or methacrylate), (poly (oxyethylene)) acrylate (or methacrylate), and (poly (oxypropylene)) acrylate (or methacrylate) having a C ₈ F ₁₇ group. Coalescence And the like can be given.

  As the surfactant, a nonionic surfactant is preferable, and a fluorine-based surfactant or a silicon-based surfactant is more preferable.

  When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0.5 mass% is more preferable.

Preparation Method of Developer The developer for photolithography of the present invention is (A) an imidazole compound represented by the general formula (1), (B) water and / or an organic solvent, in any order. C) It can be obtained by mixing and mixing various additive components such as a basic compound.

≪Resist pattern formation method≫
The present invention, as a second aspect, is a resist pattern forming method using the photolithography developer according to the first aspect of the present invention described above. The resist pattern forming method is usually
Applying a photoresist composition on a substrate to form a coating film;
A step of selectively exposing the coating film;
A step of developing a resist pattern by dissolving the non-resist portion in the exposed coating film in the above-described developer for photolithography of the present invention;
A method of forming a resist pattern by a method including: The resist pattern forming method of the present invention can be carried out by a conventionally known method except that the developing solution for photolithography according to the first aspect of the present invention described above is used in the developing step. As described above, the photolithography developer according to the first aspect of the present invention is versatile and can be suitably used in place of the conventional developer in the conventional resist pattern forming method.

  The developer for photolithography according to the first aspect of the present invention can be used for various resists regardless of whether the developer is negative or positive. Specifically, a positive resist containing a naphthoquinonediazide compound and a novolak resin, a chemical amplification containing a compound that generates an acid upon exposure, a compound that decomposes with the acid and increases its solubility in an alkaline aqueous solution, and an alkali-soluble resin Type resist, chemically amplified resist containing a compound that generates an acid upon exposure and an alkali-soluble resin having a group that decomposes by acid and increases the solubility in an alkaline aqueous solution, and is cross-linked by a compound that generates an acid upon exposure and an acid Examples thereof include a negative resist containing a crosslinking agent that initiates a reaction and an alkali-soluble resin, and a negative resist containing a compound that generates an acid upon exposure, a compound that initiates a polymerization reaction with an acid, and an alkali-soluble resin.

  The photoresist composition is suitable, for example, as a negative photoresist composition used in so-called “negative solvent development” using the photolithography developer according to the first aspect of the present invention containing (B) an organic solvent. Although it does not specifically limit as a thing, For example, the thing etc. which have a novolak resin, a polyhydroxy styrene resin, or an acrylic resin as a main component are mentioned.

An example of a suitable negative photoresist composition includes a photosensitive resin composition containing (a) a polyfunctional epoxy resin, (b) a cationic polymerization initiator, and (c) a solvent.
(A) The polyfunctional epoxy resin is not particularly limited, and can be appropriately selected from polyfunctional epoxy resins conventionally used for various applications. The epoxy equivalent is preferably 1000 or less, more preferably 500 or less. . (A) As a suitable example of a polyfunctional epoxy resin, a polyfunctional phenol novolak type epoxy resin, a polyfunctional orthocresol novolak type epoxy resin, a polyfunctional triphenyl type novolac type epoxy resin, and a polyfunctional bisphenol A novolak type epoxy resin Examples thereof include resins. In these, a polyfunctional bisphenol A novolak type epoxy resin is preferable. (A) The functionality of the polyfunctional epoxy resin is bifunctional or higher, preferably tetrafunctional or higher.
(B) As the cationic polymerization initiator, for example, an onium salt type cationic polymerization initiator such as an iodonium salt or a sulfonium salt can be used. (C) The solvent is not particularly limited.

The photoresist composition is also alkaline (B) as a positive photoresist composition used for so-called “positive development” using the developer for photolithography according to the first aspect of the present invention containing water. It not particularly limited as long as it can be developed by the developing solution, i, g-line positive photoresist composition, KrF, ArF, positive excimer laser, such as F ₂ photoresist composition, more EB (electron A widely used positive photoresist composition such as a positive photoresist composition for (line) and a positive photoresist for EUV can be used. Preferred examples include a composition containing an alkali-soluble novolak resin substituted with a quinonediazide group such as 1,2-naphthoquinonediazidesulfonyl group, and a quinonediazide group-containing compound and an alkali-soluble resin such as an alkali-soluble novolak resin. And the like.

  As a photoresist composition suitable as a chemically amplified photoresist composition, a resin (a ′) whose solubility in an organic solvent developer is reduced by the action of an acid, and an acid generated upon irradiation with actinic rays or radiation. And a compound containing the compound (b ′) and the organic solvent (c ′). Such a photoresist composition is described, for example, in Patent Document 1 described above.

  As the resin (a ′) whose solubility in an organic solvent developer is reduced by the action of an acid, the main chain or side chain of the resin, or both the main chain and the side chain are decomposed by the action of an acid, and an alkali-soluble group And a resin having a group (hereinafter also referred to as “acid-decomposable group”). Alkali-soluble groups include phenolic hydroxyl groups, carboxylic acid groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, (alkylsulfonyl) (alkylcarbonyl) Imido group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, and tris (alkylsulfonyl) methylene A carboxylic acid group, a fluorinated alcohol group (preferably hexafluoroisopropanol), and a sulfonic acid group are preferable.

  In the acid-decomposable group, the acid-dissociable group that is eliminated from the alkali-soluble group by the action of an acid can be appropriately selected from groups proposed as acid-dissociable groups in the resin for chemically amplified resist. Generally, a group that forms a cyclic or chain tertiary alkyl ester with an alkali-soluble group such as a carboxy group in (meth) acrylic acid or the like, an acetal type acid dissociable group such as an alkoxyalkyl group, or the like Widely known.

  The compound (b ') that generates an acid upon irradiation with actinic rays or radiation is not particularly limited, and various compounds conventionally used in photoresist compositions can be used. Specific examples of such compounds include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  The photoresist composition may also be a composition containing a photosensitive resin such as a photosensitive polyimide resin or a photosensitive polybenzoxazole resin. The developer for photolithography which is the first aspect of the present invention for such a photoresist composition is N, N, N ′, N′-tetramethylurea (TMU), N, N, 2 as a particularly suitable organic solvent. -What contains trimethylpropanamide (DMIB) etc. are mentioned. The developer for photolithography of the present invention for a photoresist composition containing a polyamic acid which is a precursor of a photosensitive polyimide resin contains an organic developer such as TMU and DMIB, as well as an alkaline developer containing water. A composition can be used suitably.

  A photoresist composition containing the components described above is applied to the substrate surface, and a coating film is formed on the substrate. The method for applying the photoresist composition on the substrate is not particularly limited as long as the photoresist composition can be satisfactorily applied on the substrate with a desired film thickness. Specific examples of the coating method include a spin coating method, a spray method, a roller coating method, and an immersion method, and the spin coating method is more preferable.

The type of the substrate used for forming the coating film is not particularly limited. For example, silicon, an inorganic substrate such as SiO ₂ or SiN, a coating inorganic substrate such as SOG, a semiconductor manufacturing process such as an IC, a liquid crystal, a thermal head, etc. In a resist pattern forming method using a developer for photolithography, which is a first aspect of the present invention, a substrate generally used in a circuit board manufacturing process and further in a lithography process of other photo applications can be used. In particular, an object to be coated having a portion made of metal on the surface, such as a substrate made of metal, a substrate provided with a wire made of metal, or the like can be particularly preferably used. Examples of the metal constituting the substrate, wiring, and the like include gold, copper, nickel, palladium, and the like. From the viewpoint of achieving the object of the present invention particularly effectively and high versatility, copper is particularly preferable. Can be used.

  The substrate that supports the wiring made of metal is usually an insulating substrate. Examples of the insulating substrate include an organic substrate, a ceramic substrate, a silicon substrate, and a glass substrate. The material of the organic substrate is not particularly limited, and heat such as thermosetting resin such as phenol resin, urea resin, melamine resin, alkyd resin epoxy resin, polyimide resin, polyphenylene oxide resin, polyphenylene sulfide resin, aramid resin, liquid crystal polymer, etc. A plastic resin can be used. Moreover, the material hardened after impregnating a thermosetting resin to woven fabrics or nonwoven fabrics, such as glass fiber, an aramid fiber, and an aromatic polyamide fiber, is also used suitably as a board | substrate.

  After coating a photoresist composition on a substrate to form a coating film, the coating film on the substrate may be heated (prebaked) as necessary. Thereby, the film | membrane from which the insoluble solvent was removed can be formed uniformly. The pre-baking conditions vary depending on the type of each component in the composition, the blending ratio, the coating film thickness, and the like, but usually 50 ° C to 160 ° C is preferable, 60 ° C to 140 ° C is more preferable, and about 2 to 60 minutes. It is. Moreover, the film thickness of the obtained coating film is 1-150 micrometers, Preferably it is 10-150 micrometers, More preferably, it is 20-120 micrometers, More preferably, it is the range of 20-75 micrometers.

  Next, the formed coating film is selectively exposed with active energy rays such as ultraviolet rays and electron beams so that a desired pattern is formed. The exposure method is not particularly limited, and can be appropriately selected from various conventionally known methods. As a suitable method, there is a method of irradiating the coating film with an active energy ray such as an ultraviolet ray or an electron beam through a predetermined mask.

  By this exposure, an exposed portion and an unexposed portion are formed in the coating film. When a positive photoresist composition is used, the exposed portion is used, and when a negative photoresist composition is used, the non-exposed portion becomes a non-resist portion, which is dissolved by being brought into contact with the photolithography developer of the present invention. be able to. In the case where the chemically amplified photoresist composition is used, the acid dissociable protecting group of the resin is removed in the exposed portion of the coating film as the acid is generated by exposure, and a polar group is generated in the resin. A positive resist pattern can be formed by dissolving with the developer for photolithography of the present invention containing, while in the unexposed part, the acid dissociable protective group of the resin does not come off and the state of low polarity And (B) a negative resist pattern can be formed by dissolving with the developer for photolithography of the present invention containing an organic solvent.

Examples of the active energy ray include infrared light, visible light, ultraviolet light, far ultraviolet light, X-ray, and electron beam. Among them, it is usually possible to irradiate ultraviolet light or visible light having a wavelength of 300 to 500 nm. As a radiation source of irradiation radiation, a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, an argon gas laser, etc. Can be used. The amount of radiation irradiation varies depending on the type of each component in the composition, the blending amount, the thickness of the coating film, and the like, but is, for example, 100 to 2000 mJ / cm ² when using an ultrahigh pressure mercury lamp. When a chemically amplified photoresist composition is used, far ultraviolet light having a wavelength of 250 nm or less, preferably 220 nm or less, more preferably 1 to 200 nm is preferred. Specific examples of the far ultraviolet light include ArF excimer laser, F ₂ excimer laser, EUV (13 nm), and the like.

In the exposure step, an immersion exposure method in which exposure is performed by filling the space between the optical lens portion and the resist film with an immersion medium as necessary. The immersion medium is not particularly limited as long as it is a liquid having a refractive index larger than the refractive index of air and smaller than the refractive index of the coating film to be used. As such an immersion medium, water (pure water, deionized water), a liquid in which various additives are added to water to increase the refractive index, a fluorine-based inert liquid, a silicon-based inert liquid, a hydrocarbon-based liquid An immersion medium having a high refractive index characteristic, which is expected to be developed in the near future, can be used. Examples of the fluorine-based inert liquid include liquids mainly composed of 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. It is done. Among these, water (pure water, deionized water) is preferable when using exposure light (ArF excimer laser or the like) having a wavelength of 193 nm from the viewpoint of cost, safety, environmental problems, and versatility. When using exposure light having a wavelength (such as F ₂ excimer laser), a fluorine-based inert solvent is preferable.

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

  Following the exposure, the resist pattern is developed by bringing the exposed coating film into contact with the photolithography developer of the present invention, and unnecessary portions (non-resist portions) are dissolved and removed to form a predetermined resist pattern. Get. The development time varies depending on the type of each component of the photoresist composition, the blending ratio, and the dry film thickness of the photoresist composition, but is usually 1 to 30 minutes.

  The method of developing the resist pattern with a photolithography developer is not particularly limited, and can be appropriately selected from known developing methods. As a suitable developing method, for example, a method of immersing a substrate having an exposed coating film in a photolithography developer for a certain period of time (dip method), a photolithography developer on the surface of the exposed coating film is used. A method of raising by tension and resting for a certain period of time (paddle method), a method of spraying a developer for photolithography on the surface of an exposed coating film (spray method), and a substrate rotating at a constant speed. For example, a method of continuously applying the photolithography developer while scanning the developer coating nozzle for photolithography at a constant speed toward the coating film (dynamic dispensing method) may be used.

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

After the development, a rinsing step of cleaning the resist pattern using a rinsing liquid may be performed. The rinsing liquid is not particularly limited as long as it does not dissolve the resist pattern. When (B) water is used in the photolithography developer according to the first aspect of the present invention, water can be used, and (B) organic When a solvent is used, a solution containing a general organic solvent can be used. Examples of the organic solvent that can be used as the rinsing liquid include the same organic solvents that may be contained in the photolithography developer. The rinse liquid may contain a plurality of the above organic solvents, or may contain an organic solvent other than those described above.
An appropriate amount of a surfactant can be added to the rinse solution.

  After development or rinsing, it is preferable to dry the substrate provided with the resist pattern by a known method using an air gun, an oven, or the like, if necessary.

  The resist pattern forming method of the present invention is a case where a metal substrate or wiring is heated by pre-baking or PEB, particularly PEB, by developing using the photolithography developer of the first aspect of the present invention. However, in such a substrate or wiring, infiltration of the dendritic crystal of the metal compound caused by migration into the resist pattern and oxidation of the metal surface of the substrate or wiring or formation of an oxide layer can be suppressed. In this respect, the developer for photolithography of the present invention enables protection, particularly corrosion prevention, of a metal substrate or wiring.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

[Examples and Comparative Examples]
<Imidazole compound>
Compound 1, Comparative Compound 1 and Comparative Compound 2 having the following structure were used.

[Synthesis Example 1]
Of the imidazole compounds, Compound 1 was synthesized by the following method.
First, 30 g of cinnamic acid derivative having the structure of the following formula was dissolved in 200 g of methanol, and then 7 g of potassium hydroxide was added to the methanol. The methanol solution was then stirred at 40 ° C. Methanol was distilled off and the residue was suspended in 200 g of water. To the obtained suspension, 200 g of tetrahydrofuran was mixed and stirred, and the aqueous phase was separated. Under ice cooling, 4 g of hydrochloric acid was added and stirred, and then 100 g of ethyl acetate was mixed and stirred. After allowing the mixture to stand, the oil phase was collected. The target product was crystallized from the oil phase, and the precipitate was collected to obtain an imidazole compound (compound 1) having the above structure.

The measurement result of ¹ H-NMR of the imidazole compound (compound 1) having the above structure is 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 = 4.3 Hz), 6.876 (d, 1H, J = 6.1 Hz), 5.695 (dd, 1H, J = 4.3 J, 3.2J), 3.720 (s, 3H), 3.250 (m, 2H)

[Example of preparation of developer]
As shown in Table 1, an alkaline developer containing an imidazole compound was prepared. As shown in Table 1, the solvent for the alkaline developer is a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH), a 0.04% aqueous solution of potassium hydroxide (KOH), and sodium hydroxide (NaOH). As a solvent for organic solvent development, propylene glycol monomethyl ether acetate (PGMEA) was used. The unit of the numerical value representing the content of each component in Table 1 is mass%.

[Formation of resist pattern]
A photoresist composition was applied on a copper substrate by a predetermined method to form a coating film having a thickness of 1 μm, and exposure was performed. As a photoresist composition, one of three types of resist compositions (OFPR, PMER P, TMMR; all manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used as shown in Table 1.

  The exposed coating film was developed using each developer obtained in the above preparation example. After the development, the substrate was post-baked at 230 ° C. for 20 minutes to form a resist pattern having a predetermined pattern.

After the post-baking, the cross section of the substrate was observed using a scanning electron microscope, and the presence or absence of the oxide layer was observed. When the oxide layer was formed, the interface between the substrate and the oxide layer was clearly observed in the cross section of the substrate. The thickness of the formed oxide layer was obtained from the scanning electron microscope image, and the formation of the oxide layer and the occurrence of migration were evaluated according to the following criteria. The results are shown in Table 1.
<Evaluation criteria>
A: Formation or migration of an oxide layer has not occurred.
○: Formation or migration of an oxide layer having a thickness of less than 50 nm occurs.
X: Formation or migration of an oxide layer having a thickness of 50 nm or more occurs.

  From Table 1, when developed using a photolithography developer containing Compound 1, even if the copper substrate is heated by post-baking (PEB) after development, formation of an oxide layer and occurrence of migration in the copper substrate It was found to be suppressed.

Claims (5)

(A) A developer for photolithography containing 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 that may have a substituent, R ³ is an alkylene group that may have a substituent, and R ⁴ Are each independently a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfonate group, a phosphino group, a phosphinyl group, a phosphonate group, or an organic group. It is an integer of 3.)   The developer for photolithography according to claim 1, further comprising (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 an inorganic alkali, an amine compound, and a quaternary ammonium salt.   The organic solvent (B) is at least one selected from the group consisting of ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents. The developer for photolithography according to any one of the above.   A resist pattern forming method using the photolithography developer according to claim 1.