JP4685418B2 - Fluorene derivative and photosensitive resin composition - Google Patents

Description

  The present invention is a fluorene derivative (fluorene polycarboxylic acid) which is used in combination with a photosensitive agent and is useful for forming a fine pattern such as a semiconductor integrated circuit using light rays such as ultraviolet rays and far ultraviolet rays (including excimer lasers). Ester), its manufacturing method, and the photosensitive resin composition containing the said fluorene derivative (fluorene polycarboxylic acid ester).

In the field of semiconductor resists, with the development of VLSI, more advanced microfabrication technology is required, which is shorter than conventional high pressure mercury lamp g-line (wavelength 436 nm) and i-line (wavelength 365 nm). Wavelength light sources such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), and F ₂ excimer laser (wavelength 157 nm) are used.

  In addition to the high integration of semiconductor integrated circuits, there is a demand for improved resolution (pattern formation of submicron or quarter micron or less) and improved etching resistance in a dry development process.

  However, conventional resist materials that use g-line or i-line, such as novolak resin / diazonaphthoquinone type positive resist, are light sources with short wavelengths such as KrF excimer laser and ArF excimer laser due to light absorption of novolak resin. Even if is used, sensitivity and resolving power are greatly reduced.

As resists applicable to shorter wavelength exposure sources, I. Sondi and E. Matijevic, Resist Technology and Processing XVII, Francis M. Houlihan, Editor, Proceedings of SPIE Vol. 3999 (2000) (Non-patent Document 1) the first 627 to 637 pages), composed of p- hydroxystyrene -t- butyl acrylate copolymer containing SiO ₂ nanoparticles (sol) film is disclosed, resist containing such SiO ₂ nanoparticles It is described that a high resolution and a resist system using transparent SiO ₂ nanoparticles are useful for wavelengths such as 157 nm. However, with such a method, the difference in dissolution rate between the exposed area and the unexposed area cannot be increased, and the resolution cannot be improved sufficiently.

On the other hand, Japanese Patent Laid-Open No. 2002-363123 (Patent Document 1) discloses a photoactivity capable of generating a hydrophilic group (hydroxyl group, carboxyl group, etc.) in association with a photosensitive agent such as a photoacid generator by light irradiation. It is described that the sensitivity and resolution of a resist can be improved by adding a compound to a positive photosensitive resin or the like. In this document, a fluorene compound in which the hydroxyl group of bis (hydroxyphenyl) fluorenes is protected with a hydrophobic protecting group is disclosed as the photoactive compound. However, even with such a fluorene compound, the difference in dissolution rate between the exposed portion and the unexposed portion cannot be increased, and the sensitivity and resolution cannot be sufficiently improved.
JP 2002-363123 A (claim 14, paragraph number [0072]) "I. Sondi and E. Matijevic, Resist Tecnology and Processing XVII, Francis M. Houlihan, Editor, Proceedings of SPIE Vol. 3999 (2000), pp. 627-637"

  Therefore, the object of the present invention is to increase the solubility difference between the exposed portion and the unexposed portion with respect to the developer in combination with the photosensitive agent, and to effectively improve the sensitivity and resolution of the resist, a fluorene derivative (fluorene polycarboxylic acid). Acid ester), a production method thereof, and a photosensitive resin composition using the acid ester.

  Another object of the present invention is a fluorene derivative (fluorene polycarboxylic acid ester) that is highly sensitive to a short wavelength exposure source and is useful for forming a fine pattern with high resolution, a method for producing the same, and the It is providing the photosensitive resin composition using this.

  Still another object of the present invention is to provide a method for easily and efficiently producing a novel fluorene derivative (fluorene polycarboxylic acid ester) useful for improving the sensitivity and resolution of a resist.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that a novel fluorene polycarboxylic acid ester obtained by protecting a fluorene polycarboxylic acid (such as fluorene tetracarboxylic acid) with a protective group is converted into an existing short wavelength resist material ( When added to KrF resist materials, etc.), the protective group is easily deprotected by the action of a photosensitizer such as a photoacid generator, thereby producing fluorene polycarboxylic acids having excellent heat resistance and strong hydrophilicity. It was found that the sensitivity and resolution can be improved easily and remarkably, and the present invention has been completed.

  That is, the fluorene derivative (fluorene polycarboxylic acid or ester thereof) of the present invention is represented by the following formula (1).

[Wherein, R ^1a and R ^1b represent the same or different substituents, and R ^2a and R ^2b represent the same or different divalent hydrocarbon groups which may have a substituent, or (2)

(In the formula, R ⁴ represents a hydrogen atom or a hydrocarbon group, R ⁵ represents a divalent hydrocarbon group which may have a substituent, p is 0 or 1, and R ^3e is a hydrogen atom or a carboxyl group. Indicates a protecting group for the group.)
And R ^{3a to} R ^3d are the same or different and represent a protecting group for a hydrogen atom or a carboxyl group, and k, j, m and n are the same or different and are an integer of 0 to 4, j + k ≦ 4, m + n ≦ 4. However, when j = m = 0, at least one of R ^2a and R ^2b is a group represented by the formula (2). ]
In the formula (1), the groups R ^2a and R ^2b are, for example, (i) a divalent hydrocarbon group such as an alkylene group, a cycloalkylene group, or an alkylene-arylene group, and (ii) in the formula (2) R ⁴ may be a hydrogen atom, an alkyl group or an aryl group, and R ⁵ may be a divalent group such as an alkylene group (such as a C _1-4 alkylene group). In a typical embodiment, in Formula (1), R ^2a and R ^2b are a C _1-6 alkylene group, a C _5-8 cycloalkyl C _1-4 alkylene group, a C _6-10 aryl C _1-4 alkylene. A group, a C _5-8 cycloalkylene group, a C _1-4 alkylene-C _6-10 arylene group, a group in which R ⁴ is a hydrogen atom and R ⁵ is a C _1-4 alkylene group in the formula (2) In the formula (2), R ⁴ is a C _1-4 alkyl group and R ⁵ is a C _1-4 alkylene group, and in the formula (2), R ⁴ is a C _6-10 aryl group. And a divalent group selected from the group in which R ⁵ is a C _1-4 alkylene group.

The fluorene derivative represented by the formula (1) is usually a compound (fluorene polycarboxylic acid ester) in which at least one carboxyl group (particularly, all carboxyl groups) is protected by a protective group (protective group for the carboxyl group). ). For example, in the formula (1), at least one of R ^{3a to} R ^3e may be a hydrophobic protecting group that can be eliminated by the action of an acid to generate a carboxyl group. In a preferred embodiment, all of R ^{3a to} R ^3e may be an alkyl group (particularly a t-butyl group).

  Representative fluorene derivatives represented by the formula (1) include, for example, fluorene tetracarboxylic acid esters represented by the following formula (1A) or (1B).

(In the formula, R ^20a and R ^20b are divalent hydrocarbon groups which may have a substituent, R ^{30a to} R ^30d represent an alkyl group. R ^1a , R ^1b , k and n are as defined above. the same.)

(In the formula, R ^30e represents an alkyl group. R ^1a , R ^1b , R ^30c , R ^30d , R ⁴ , k and n are the same as described above.)
Such representative fluorene derivatives (fluorene polycarboxylic acid esters) include fluorene polycarboxylic acid alkyl esters such as bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C). _1-6 alkyl) fluorenes, bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C _5-8 cycloalkyl) fluorenes, bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C _6-10 aryl-C _1-4 alkyl) fluorenes, or 9,9-bis [1,2-di (C _1-4 alkoxycarbonyl) ethyl ] -Fluorenes may be used.

  Although the manufacturing method of the said fluorene derivative (fluorene derivative represented by Formula (1)) is not restrict | limited in particular, For example, it represents with following formula (3) under a basic catalyst (in the presence of a basic catalyst). You may manufacture by the method of including at least the process of making fluorenes and the carboxylic acid ester represented by following formula (4) react.

{Wherein R ³ represents a protecting group for a carboxyl group, R ⁶ -represents X—R ² — (wherein R ² represents a divalent hydrocarbon group which may have a substituent, X Represents a halogen atom), or CHR ⁸ ═CR ⁷ — [wherein R ⁷ and R ⁸ are the same or different and represent a hydrogen atom, a hydrocarbon group or — (R ⁵ ) _p —COOR ³ (wherein R ³ , R ⁵ and p are the same as above. However, R ⁷ and R ⁸ - (R ⁵⁾ is not a _p -COOR ^3. R ^1a , R ^1b , j, k, m and n are the same as above. However, when j = m = 0, in the carboxylic acid ester represented by the formula (4), R ⁶ — is CHR ⁸ ═CR ⁷ —, and one of R ⁷ and R ⁸ is — ( R ⁵⁾ comprising at least a carboxylic acid ester is _p -COOR ^3. }
The fluorene derivative (particularly fluorene polycarboxylic acid ester) of the present invention is useful for constituting a photosensitive resin composition. Such a photosensitive resin composition may be composed of the fluorene derivative (particularly, fluorene polycarboxylic acid ester), a base resin, and a photosensitive agent. In a typical photosensitive resin composition, the base resin may be composed of a resin that generates a hydrophilic group by the action of an acid (or a resin that can be generated), and the photosensitive agent may be composed of a photoacid generator. . In the photosensitive resin composition, the ratio (weight ratio) between the fluorene derivative and the photosensitizer may be, for example, the former / the latter = 0.01 / 1 to 100/1. In the photosensitive resin composition, the amount of the photosensitive agent used may be about 0.1 to 50 parts by weight with respect to 100 parts by weight of the base resin, and the amount of the fluorene derivative used may be the base resin and the photosensitive resin. About 0.1-30 weight part may be sufficient with respect to 100 weight part of total amounts of an agent.

  The present invention also includes a method in which the photosensitive resin composition is applied to a substrate, exposed to light, then subjected to heat treatment, and further developed to form a pattern.

  The fluorene derivative of the present invention (especially fluorene polycarboxylic acid ester) has high hydrophobicity due to the fluorene skeleton (and hydrophobic protective group), and also has a hydrophilic property by easily deprotecting the protective group. Since it can produce highly carboxyl groups, the difference in solubility in the developer between the exposed and unexposed areas can be greatly increased in combination with a photosensitizer (such as a photoacid generator), which significantly increases the sensitivity and resolution of the resist. It can be improved. Moreover, it is highly sensitive to a short wavelength exposure source and can form a fine pattern with high resolution. Furthermore, in this invention, the said fluorene derivative (fluorene polycarboxylic acid ester) can be manufactured simply and efficiently by applying a well-known reaction.

  The fluorene derivative of the present invention is a fluorene polycarboxylic acid represented by the following formula (1) or an ester thereof.

[Wherein, R ^1a and R ^1b represent the same or different substituents, and R ^2a and R ^2b represent the same or different divalent hydrocarbon groups which may have a substituent, or (2)

(In the formula, R ⁴ represents a hydrogen atom or a hydrocarbon group, R ⁵ represents a divalent hydrocarbon group which may have a substituent, p is 0 or 1, and R ^3e is a hydrogen atom or a carboxyl group. Indicates a protecting group for the group.)
And R ^{3a to} R ^3d are the same or different and represent a protecting group for a hydrogen atom or a carboxyl group, and k, j, m and n are the same or different and are an integer of 0 to 4, j + k ≦ 4, m + n ≦ 4. However, when j = m = 0, at least one of R ^2a and R ^2b is a group represented by the formula (2). ]
The substituents represented by the groups R ^1a and R ^1b are not particularly limited, and may be various substituents described later, but are usually alkyl groups in many cases. Examples of the alkyl group include C _1-6 alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a t-butyl group (for example, a C _1-4 alkyl group, particularly a methyl group). Preferred substitution numbers k and n are 0 or 1, in particular 0. The bonding position of the groups R ^1a and R ^1b to the benzene ring constituting the fluorene ring is not particularly limited, and can be selected according to the substitution position of the groups represented by the group —COOR ^3a and the group —COOR ^3b .

The number of substitutions j and m can be selected according to the type of groups R ^2a and R ^2b described later, and may preferably be 0 or 1. In addition, if the substitution position of the group (carboxyl group or its ester group) represented by the group -COOR ^3a and the group -COOR ^3b is an appropriate position at positions 1 to 8 of the benzene ring constituting the fluorene skeleton, respectively. Well, when j = m = 1, for example, it may be the 2nd and 7th positions.

The divalent group represented by the groups R ^2a and R ^2b depends on the production method of a fluorene derivative described later (a method using a halogenated carboxylic acid ester, a method using an α, β-unsaturated carboxylic acid ester) and the like. The group to be determined.

Examples of the divalent hydrocarbon group which may have a substituent represented by the groups R ^2a and R ^2b include an aliphatic hydrocarbon group which may have a substituent (an aliphatic carbon group such as an alkylene group). Hydrogen group), an alicyclic hydrocarbon group which may have a substituent [an alicyclic hydrocarbon group such as a cycloalkylene group, an alicyclic aliphatic group such as an alkylene-cycloalkylene group (or cycloalkylene-alkylene group) Aromatic hydrocarbon groups, bridged cyclic hydrocarbon groups such as bi- or tricycloalkylene groups (such as norbornane-diyl group and adamantane-diyl group)], and optionally substituted aromatic hydrocarbon groups [alkylene -An araliphatic hydrocarbon group such as an arylene group (or an arylene-alkylene group)] and the like. The alkylene-cycloalkylene group and the alkylene-arylene group are groups represented by —R ^a —R ^b — (wherein R ^a represents an alkylene group and R ^b represents a cycloalkylene group or an arylene group). Show.

Examples of the substituent substituted for the divalent hydrocarbon group include alkyl groups (C _1-6 alkyl groups such as methyl and ethyl groups, preferably C _1-4 alkyl groups, depending on the type of the divalent hydrocarbon group. And more preferably a C _1-2 alkyl group), a cycloalkyl group (such as a C _5-8 cycloalkyl group such as a cyclopentyl group or a cyclohexyl group), an aryl group (a C _6-10 aryl group such as a phenyl group), Preferably C _6-8 aryl group), aralkyl group (C _6-10 aryl-C _1-4 alkyl group such as benzyl group), alkoxy group (C _1-4 alkoxy group such as methoxy group), acyl Group (C _1-6 acyl group such as acetyl group), alkoxycarbonyl group (C _1-4 alkoxycarbonyl group such as methoxycarbonyl group), halogen atom (fluorine atom, chlorine atom etc.), nitro group, cyano Group and the like. The divalent hydrocarbon group may be substituted alone or in combination of two or more.

An alkylene group which may have a substituent [or an alkylidene group (such as a methylene group), hereinafter, unless otherwise specified, the alkylene group and the alkylidene group are collectively referred to as “alkylene group”] Is, for example, an alkylene group [methylene group, ethylene group, ethylidene group, n-propylene group (trimethylene group), propylene group, propylidene group (propane-1-ylidene group), isopropylidene group (propane-2-ylidene group) , Tetramethylene group, ethylethylene group (butane-1,2-diyl group), butane-2-ylidene group, 1,2-dimethylethylene group (butane-2,3-diyl group), pentamethylene group, pentane- 2,3-diyl group, C _1-12 alkylene group (preferably C _1-8 alkylene groups such as a hexamethylene group, still more preferably The C _1-6 alkylene group, in particular, C _1-4 alkylene group)], cycloalkyl alkylene group [cyclohexyl ethylene group, (methylcyclohexyl) ethylene group [(such as 4-methylcyclohexyl) ethylene group], such as C _{5- 10} cycloalkyl C _1-8 alkylene group (preferably C _5-8 cycloalkyl C _1-4 alkylene group, more preferably C _5-6 cycloalkyl C _1-2 alkylene group) and the like], aryl alkylene group [phenylethylene Groups, C _6-10 aryl C _1-8 alkylene groups such as _{tolylethylene} group and xylylethylene group (preferably C _6-10 aryl C _1-4 alkylene group, more preferably C _6-8 aryl C _{1-2 group)} Alkylene group) and the like].

Examples of the cycloalkylene group which may have a substituent include a cyclopentylene group, a cyclohexylene group (1,4-cyclohexylene group, a cyclohexylidene group (such as a cyclohexane-1-ylidene group)), and the like. C _5-10 cycloalkylene group (preferably C _5-8 cyclohexane) which may have a substituent such as methylcyclohexylene group (such as 2-methyl-1,4-cyclohexylene group) and cycloheptylene group. An alkylene group, and more preferably a C _5-6 cycloalkylene group). The alkylene-cycloalkylene group optionally substituted (in the formula -R ^a -R ^b- , where R ^a is an alkylene group and R ^b is a cycloalkylene group) is the alkylene group exemplified above And a cycloalkylene group bonded to each other, for example, methylene-cyclohexylene group [—CH ₂ —C ₆ H ₁₀ —] (methylene-1,4-cyclohexylene group, etc.), ethylene-cyclohexylene group [ _{-CH 2 CH 2 -C 6 H 10} -] ( ethylene-1,4-cyclohexylene or xylene group), an ethylene - methylcyclohexane hexylene group (ethylene-2-methyl-1,4-cyclohexylene or xylene group), ethylidene - cyclohexylene group _{[-CH (CH 3) -C 6} H 10 -] ( ethylidene-1,4-cyclohexylene or xylene group) a C _1-6 alkylene optionally having a substituent such as - _5-10 cycloalkylene group (preferably a C _1-4 alkylene -C _5-8 cycloalkylene group, more preferably a C _1-2 alkylene -C _5-6 cycloalkylene group), and others. In the alkylene-cycloalkylene group which may have a substituent, the alkylene group is often bonded (or substituted) to the 9-position of fluorene.

Examples of the alkylene-arylene group optionally substituted (in the formula -R ^a -R ^b- , where R ^a is an alkylene group and R ^b is an arylene group) include the above-exemplified alkylene groups and arylenes. A group bonded to a group, for example, methylene-phenylene group [—CH ₂ —C ₆ H ₄ —] (methylene-1,4-phenylene group, etc.), ethylene-phenylene group [—CH ₂ CH ₂ —C ₆ H ₄ - (ethylene-1,4-phenylene), ethylene - (ethylene-2-methyl-1,4-phenylene) methyl phenylene group, ethylidene phenylene group _{[-CHCH 3 -C 6 H 4 -} ] A C _1-6 alkylene-C _6-20 arylene group (preferably a C _1-4 alkylene-C _6-10 arylene group) which may have a substituent such as an ethylidene-1,4-phenylene group, More preferred And C _1-2 alkylene-C _6-8 arylene, particularly C _1-2 alkylene-phenylene group). In the alkylene-arylene group which may have a substituent, the alkylene group is often bonded (or substituted) to the 9-position of fluorene.

  In addition, the above-exemplified divalent hydrocarbon groups (alkylene group, cycloalkylene group, arylene-alkylene group, etc.) are further substituted with the above-exemplified substituents (alkoxy group, halogen atom, acyl group, etc.). Includes one or more substituted hydrocarbon groups.

The divalent group represented by the groups R ^2a and R ^2b may be a group represented by the formula (2), that is, a group having a carboxyl group or an ester group. In addition, such a fluorene derivative having groups R ^2a and R ^2b is obtained by using an α, β-unsaturated dicarboxylic acid diester as the compound represented by the formula (4) in the method for producing a fluorene derivative described later. Obtainable.

Examples of the hydrocarbon group represented by the group R ⁴ include hydrocarbon groups (monovalent hydrocarbon groups) corresponding to the divalent hydrocarbon groups exemplified above, for example, alkyl groups (C ₁ such as methyl and ethyl groups). _-6 alkyl group, preferably C _1-4 alkyl group, more preferably C _1-2 alkyl group etc.), cycloalkyl group (C _5-8 cycloalkyl group such as cyclopentyl group, cyclohexyl group etc.), aryl Group (C _6-10 aryl group such as phenyl group, preferably C _6-8 aryl group), aralkyl group (C _6-10 aryl-C _1-4 alkyl group such as benzyl group) and the like. Preferred groups R ⁴ are a hydrogen atom, an alkyl group (such as a C _1-4 alkyl group such as a methyl group), an aryl group (a C _6-10 aryl group such as a phenyl group, preferably a C _6-8 aryl group). In particular, a hydrogen atom is preferable.

Examples of the divalent hydrocarbon group which may have a substituent represented by the group R ⁵ include the same divalent hydrocarbon groups as described above. For example, the divalent hydrocarbon group may have a substituent. And an aliphatic hydrocarbon group (an aliphatic hydrocarbon group such as an alkylene group). A preferred group R ⁵ is an alkylene group (eg a C _1-4 alkylene group such as a methylene group), in particular a methylene group. In the formula (2), p may be 0 or 1, and p is preferably 0.

In addition, the direction of the bond (or substitution) of the group represented by the formula (2) with respect to the 9-position of the fluorene skeleton is not particularly limited, and the carbon atom substituted with the group R ⁴ or the group — (R ⁵ ) _p — Any of the carbon atoms substituted by COOR ^3e may be bonded to the 9-position of fluorene. When p is 0, the group — (R ⁵ ) _p —COOR ^3e is usually bonded to the 9-position of fluorene [ie, the group —CH (COOR ^3e ) —CHR ⁴ —COOR ^3c (or R ^3d ) is often bonded to the 9-position of fluorene].

Preferred groups R ^2a and R ^2b include (i) an alkylene group (C _1-6 alkylene group, C _5-8 cycloalkyl C _1-4 alkylene group, C _6-10 aryl C _1-4 alkylene group, etc.), Divalent carbonization such as a cycloalkylene group (such as a C _5-8 cycloalkylene group) and the above-described group —R ^a —R ^b — (or an alkylene-arylene group, a C _1-4 alkylene-C _6-10 arylene group, etc.) A hydrogen group, (ii) In the above formula (2), R ⁴ is a hydrogen atom, an alkyl group (such as a C _1-4 alkyl group) or an aryl group (such as a C _6-10 aryl group), and R ⁵ is an alkylene group a (C _1-4, etc. alkylene group), p is the like divalent group is 0 or 1 (in particular, 0).

The protecting group represented by the groups R ^{3a to} R ^3e (protecting group for the carboxyl group) is not particularly limited, but is a hydrophobic protecting group (hydrophobic that can be eliminated by the action of an acid to generate a carboxyl group). Preferred protecting groups). Such a hydrophobic protecting group may have a substituent such as a methyl group, an ethyl group, an isopropyl group, a 2-cyclohexyl-2-propyl group, a butyl group, an s-butyl group, or a t-butyl group. A good C _1-6 alkyl group (preferably a C _1-5 alkyl group, more preferably a C _1-4 alkyl group, especially a branched C _3-4 alkyl group such as a C _1-2 alkyl group or a t-butyl group) ); C _3-8 cycloalkyl group optionally having a substituent such as cyclohexyl group, 1-methylcyclohexyl group; decalinyl group (such as 2-methyl-2-decalinyl group), adamantyl group (2-methyl-) A bi- or tricycloalkyl group (bridged hydrocarbon group) which may have a substituent such as a 2-adamantyl group and the like, and a norbornyl group (such as a 2-methyl-2-norbornyl group); 2,4- Dinitrophenyl An aryl group which may have a substituent such as; benzyl, 2,6-dichlorobenzyl group, 2-nitrobenzyl group, which may have a substituent such as triphenylmethyl group C _{6- 10} aryl-C _1-4 alkyl group; optionally substituted oxa C _5-8 cycloalkyl group such as tetrahydrofuranyl group (such as 3-methyltetrahydrofuran-3-yl group); γ-butyrolactone ring group It may have a substituent such as a 4-methyltetrahydro-2-furan-4-yl group or a δ-valerolactone ring group (such as a 4-methyltetrahydro-2-pyron-4-yl group). A lactone ring group and the like are included.

Among these protecting groups, a protecting group that can be easily removed by an acid, for example, an alkyl group (for example, a C _1-4 alkyl group) is preferable, and in particular, a branched C _3-4 alkyl group (usually t-butyl). Group) is preferred.

The fluorene derivative represented by the formula (1) may be a compound in which all of R ^{3a to} R ^3e are hydrogen atoms (that is, fluorene polycarboxylic acid). When used as a constituent component of the above, it usually has at least a carboxyl group (—COOR ³ ) protected by a protecting group for a carboxyl group (such as a C _1-4 alkyl group). That is, in the formula (1), at least one of R ^{3a to} R ^3e is often the protecting group (in particular, a hydrophobic protecting group that can be eliminated by the action of an acid to generate a carboxyl group). In a preferred embodiment, in the formula (1), all carboxyl groups are protected [that is, all of R ^{3a to} R ^3e are the protecting groups (such as alkyl groups such as t-butyl group)]. Many. Further, the number of such protected carboxyl groups is preferably 2 or more (that is, 2 to 6), more preferably 4 to 6 (particularly 4), per the fluorene derivative. .

Representative fluorene derivatives include, for example, in the above formula (1), (i) j = m = 1, R ^2a and R ^2b are divalent hydrocarbon groups, and groups R ^{3a to} R ^3d are Fluorene polycarboxylic acid ester (fluorene tetracarboxylic acid ester) as a protecting group, (ii) j = m = 0, R ^2a and R ^2b are divalent groups represented by the formula (2), Examples include fluorene polycarboxylic acid ester (fluorene tetracarboxylic acid ester) in which the groups R ^{3a to} R ^3e are protecting groups.

  Examples of the fluorene polycarboxylic acid ester (i) include a fluorene tetracarboxylic acid alkyl ester (tetraalkyl ester) represented by the following formula (1A).

(In the formula, R ^20a and R ^20b are divalent hydrocarbon groups which may have a substituent, R ^{30a to} R ^30d represent an alkyl group. R ^1a , R ^1b , k and n are as defined above. the same.)
In the above formula (1A), R ^20a and R ^20b are each a divalent hydrocarbon group corresponding to R ^2a and R ^2b , and preferred embodiments are the same as described above. In addition, the groups R ^{30a to} R ^30d are the same as the alkyl groups (C _1-4 alkyl group and the like) exemplified in the paragraph of the protective group, and particularly preferably a t-butyl group.

  Specific examples of the fluorene tetracarboxylic acid alkyl ester represented by the formula (1A) include bis (alkoxycarbonyl) -9,9-bis (alkoxycarbonyl-alkyl) fluorenes and bis (alkoxycarbonyl) -9. , 9-bis (alkoxycarbonyl-cycloalkyl) fluorenes, bis (alkoxycarbonyl) -9,9-bis (alkoxycarbonyl-aryl-alkyl) fluorenes, and the like.

Bis (alkoxycarbonyl) -9,9-bis (alkoxycarbonyl-alkyl) -fluorenes include bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C _1-6 Alkyl) fluorenes such as 2,7-bis (t-butoxycarbonyl) -9,9-bis (t-butoxycarbonylmethyl) fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [2- (t-Butoxycarbonyl) ethyl] fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [1- (t-butoxycarbonyl) ethyl] fluorene, 2,7-bis (t -Butoxycarbonyl) -9,9-bis [2- (t-butoxycarbonyl) -1-cyclohexylethyl] fluorene, 2,7-bis (t-butoxy Rubonyl) -9,9-bis [2- (t-butoxycarbonyl) -1-phenylethyl] fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [1- (t-butoxycarbonyl) ) Propyl] fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [2- (t-butoxycarbonyl) propyl] fluorene, 2,7-bis (t-butoxycarbonyl) -9,9 -Bis [2- (t-butoxycarbonyl) -1-methylethyl] fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [2- (t-butoxycarbonyl) -1-methylpropyl ] Fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [2- (t-butoxycarbonyl) butyl] fluorene, 2,7-bis (t-butoxy) Carbonyl) -9,9-bis [2- (t-butoxycarbonyl) -1-methylbutyl] fluorene, 2,7-bis (t-butoxycarbonyl) -9,9-bis [5- (t-butoxycarbonyl) Pentyl] fluorene, etc. Bis (C _1-4 alkoxycarbonyl) optionally having a substituent (C _1-4 alkyl group, C _5-8 cycloalkyl group, C _6-10 aryl group, etc.) -9,9-bis (C _1-4 alkoxycarbonyl-C _1-6 alkyl) fluorene and the like are included.

Bis (alkoxycarbonyl) -9,9-bis (alkoxycarbonyl-cycloalkyl) fluorenes include bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C _5-8 Cycloalkyl) fluorenes such as 2,7-bis (t-butoxycarbonyl) -9,9-bis [4- (t-butoxycarbonyl) cyclohexyl] fluorene, 2,7-bis (t-butoxycarbonyl)- Bis (C _1-4 alkoxycarbonyl) -9,9-bis (C ₁ ) which may have a substituent on a cycloalkyl group such as 9,9-bis [1- (t-butoxycarbonyl) cyclohexyl] fluorene _-4 alkoxycarbonyl -C _5-8 cycloalkyl) include fluorene and the like.

Bis (alkoxycarbonyl) -9,9-bis (alkoxycarbonyl-aryl-alkyl) fluorenes include bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C _{6- 10} aryl-C _1-4 alkyl) fluorenes, for example, aralkyl groups such as 2,7-bis (t-butoxycarbonyl) -9,9-bis [4- (t-butoxycarbonyl) benzyl] fluorene (aryl- Bis (C _1-4 alkoxycarbonyl) -9,9-bis (C _1-4 alkoxycarbonyl-C _6-10 aryl-C _1-4 alkyl) fluorene which may have a substituent on the alkyl group), etc. Is included.

  The fluorene polycarboxylic acid ester (ii) includes a fluorene tetracarboxylic acid alkyl ester (tetraalkyl ester) represented by the following formula (1B).

(In the formula, R ^30e represents an alkyl group. R ^1a , R ^1b , R ^30c , R ^30d , R ⁴ , k and n are the same as described above.)
In the above formula (1B), the groups R ^{30a to} R ^30e are the same as the alkyl groups (C _1-4 alkyl group and the like) exemplified in the paragraph of the protective group, and are particularly preferably t-butyl groups. .

Specific examples of the fluorene tetracarboxylic acid alkyl ester represented by the formula (1B) include 9,9-bis [1,2-di (C _1-4 alkoxycarbonyl) ethyl] -fluorenes {for example, 9,9-bis [1,2-di (t-butoxycarbonyl) ethyl] -fluorene; 9 such as 9,9-bis [1,2-di (t-butoxycarbonyl) -2-methylethyl] -fluorene , 9-bis [1,2-di (C _1-4 alkoxycarbonyl) -2-C _1-4 alkylethyl] -fluorene; 9,9-bis [1,2-di (t-butoxycarbonyl) -2 A substituent such as 9,9-bis [1,2-di (C _1-4 alkoxycarbonyl) -2-C _6-8 arylethyl] -fluorene, etc.} such as -phenylethyl] -fluorene; 9,9-bis [1, - di (C _1-4 alkoxycarbonyl) ethyl] - fluorene and the like.

(Method for producing fluorene derivative)
When fluorenes are reacted with a base, a fluorene anion is generated. By using the generated fluorene anion as a nucleophilic agent and nucleophilic substitution reaction with aldehydes (paraformaldehyde, etc.), a substituent is placed at the 9th position of fluorene. Is known (see, for example, Synthesis (1992), (9), 819-20 (819-1820)). In the present invention, by applying such a method, the fluorene derivative represented by the formula (1) can be obtained simply and efficiently.

  That is, the fluorene derivative represented by the formula (1) includes, for example, a fluorene represented by the following formula (3) and a carboxylic acid ester represented by the following formula (4) under a basic catalyst. It can be simply and manufactured by a method including at least a step of reacting (a reaction for producing a fluorene polycarboxylic acid ester).

{Wherein R ³ represents a protecting group for a carboxyl group, R ⁶ -represents X—R ² — (wherein R ² represents a divalent hydrocarbon group which may have a substituent, X Represents a halogen atom), or CHR ⁸ ═CR ⁷ — [wherein R ⁷ and R ⁸ are the same or different and represent a hydrogen atom, a hydrocarbon group or — (R ⁵ ) _p —COOR ³ (wherein R ³ , R ⁵ and p are the same as above. However, R ⁷ and R ⁸ - (R ⁵⁾ is not a _p -COOR ^3. R ^1a , R ^1b , j, k, m and n are the same as above. However, when j = m = 0, in the carboxylic acid ester represented by the formula (4), R ⁶ — is CHR ⁸ ═CR ⁷ —, and one of R ⁷ and R ⁸ is — ( R ⁵⁾ comprising at least a carboxylic acid ester is _p -COOR ^3. }
That is, in the formula (4), the groups R ² , R ⁷ and R ⁸ correspond to the groups R ^2a and R ^2b in the formula (1). Specifically, among the compounds represented by the formula (4), when (i) a halogenated carboxylic acid ester (X—R ² —COOR ³ ) in which the group R ⁶ — is X—R ² — is used. Fluorene polycarboxylic acid ester in which two groups corresponding to the substitution position of the halogen atom X are substituted at the 9-position of the fluorenes represented by the formula (3) (in the formula (1), R ^{3a to} R ^3e (Ii) an α, β-unsaturated carboxylic acid ester (CHR ⁸ ═CR ⁷ — in which the group R ⁶ — is CHR ⁸ ═CR ⁷ —). When COOR ³ ) is used, a fluorene polycarboxylic acid ester in which the 9-position of the fluorene represented by the formula (3) is added to the β-position of the unsaturated carboxylic acid ester can be obtained.

Further, in the above aspect (ii), one of the R ⁷ and R ^8, - (R ⁵⁾ _p is a -COOR ³ alpha, beta-unsaturated dicarboxylic acid diester (i.e., the following formula (4a) or When the compound represented by (4b) is used, a fluorene polycarboxylic acid ester in which the group R ^2a and / or R ^2b in the formula (1) is a group represented by the formula (2) is obtained. Can do.

(In the formula, R ³ , R ⁵ , R ⁷ , R ⁸ and p are the same as above.)
Further, in the formulas (3) and (4), R ³ is a protecting group for a carboxyl group corresponding to R ^{3a to} R ^3e (for example, an alkyl group such as a t-butyl group). In the above formula (1), the fluorene derivative in which at least one of R ^{3a to} R ^3e is a hydrogen atom can be prepared by, for example, the group R ³ (protecting group for carboxyl group) by a conventional method. It can be obtained by deprotection.

The fluorenes represented by the formula (3) correspond to the fluorene derivatives represented by the formula (1), and the modes of R ^1a , R ^1b , j, k, m and n are the same as described above. It is. Representative fluorenes include fluorenes (such as fluorene), dicarboxyfluorene diesters [for example, di (alkoxycarbonyl) fluorenes such as 2,7-di (t-butoxycarbonyl) fluorene (especially di (C _1-4 alkoxycarbonyl) fluorene) and the like].

  In the halogenated carboxylic acid ester (i), examples of the halogen atom represented by the group X include a chlorine atom, a bromine atom, and an iodine atom. From the viewpoint of reactivity (nucleophilic substitution reactivity), a bromine atom, An iodine atom is preferred.

As described above, since the substitution position of the group X corresponds to the substitution position with respect to the 9th position of the fluorenes, the halogenated carboxylic acid ester substituted with the group X according to the type of the group R ² and the group R ³ (I) may be appropriately selected and used. Examples of halogenated carboxylic acid alkyl esters in which the group R ³ is an alkyl group are shown below. Halogenated carboxylic acid alkyl ester includes halogenated aliphatic carboxylic acid alkyl ester [haloalkane carboxylic acid alkyl ester (for example, methyl 2-bromoacetate, ethyl 2-bromoacetate, t-butyl 2-bromoacetate, 2-bromopropion] Acid methyl, ethyl 2-bromopropionate, t-butyl 2-bromopropionate, methyl 3-bromopropionate, ethyl 3-bromopropionate, t-butyl 3-bromopropionate, t-butyl 3-iodopropionate 2-bromo-2-methylpropionic acid ethyl, 2-bromo-2-methylpropionic acid t- butyl, alpha-bromo-butyric acid t- butyl, 6-bromo -n- hexane halo such as acid t- butyl C _{2- 12} Alkanecarboxylic acid C _1-6 alkyl ester (especially halo C _2-12 alkanecarboxylic acid t -Butyl ester) and the like], halogenated alicyclic carboxylic acid alkyl ester [halocycloalkanecarboxylic acid alkyl ester (methyl 4-bromocyclohexanecarboxylate, 4-bromocyclohexanecarboxylic acid-t-butyl, 1-bromocyclohexane] Halo C _5-8 cycloalkane carboxylic acid C _1-6 alkyl esters such as methyl carboxylate (especially halo C _5-8 cycloalkane carboxylic acid t-butyl ester) and the like], haloalkyl arene carboxylic acid alkyl esters (eg Haloalkyl C _6-10 arene carboxylic acids C _1-6 alkyl esters such as halo C _1-4 alkyl benzoic acid C _1-6 alkyl esters such as bromomethyl benzoate t-butyl (such as 4-bromomethyl benzoate t-butyl) (In particular, haloalkyl C _6-10 arenecarbo Acid t-butyl ester)) and the like.

The halogenated carboxylic acid ester (i) may be synthesized by a conventional method such as halogenation or esterification, if necessary. For example, the halogenated carboxylic acid ester (i) is obtained by esterification using the corresponding halogenated carboxylic acid or acid halide (chloride, bromide, etc.) according to the type of the group R ^3. at best, by using a different halogenated carboxylic acid ester in (b) R ³ (such as methyl ester), depending on the type of group R ^3, may also be transesterified, (c) the corresponding unsaturated carboxylic acid It may be obtained by electrophilic addition of a hydrogen halide (such as hydrogen bromide) to an ester (such as an α, β-unsaturated carboxylic acid ester). (D) When the α position is halogenated, the corresponding saturation It may be obtained by reacting a carboxylic acid ester, an alkali (such as lithium diisopropylamide) and a halide (such as carbon tetrabromide).

The unsaturated carboxylic acid ester (ii) forms a group —CHR ⁷ —CHR ⁸ — by addition of fluorene (or a fluorene anion), and this group is converted to the group R ² (or R ^2a and R ^2b ). It corresponds. That is, when an unsaturated carboxylic acid ester (ii) is used, a group (9-fluorenyl group or the like) corresponding to the 9-position of fluorenes is added to the β-position of the unsaturated carboxylic acid ester (ii) (1,4- Addition, Michael addition), and the groups R ⁷ and R ⁸ can be appropriately selected depending on the group R ² . The hydrocarbon group represented by the group R ⁷ and the group R ⁸ (or the group CHR ⁷ = CR ⁸ —) is the same hydrocarbon group as described above, for example, an alkyl group (C _{1- 4} alkyl group), cycloalkyl group (C _5-8 cycloalkyl group such as cyclohexyl group), aryl group (C _6-10 aryl group such as phenyl group) and the like. Preferred groups R ⁷ and R ⁸ are a hydrogen atom, an alkyl group [for example, a C _1-4 alkyl group (particularly a C _1-2 alkyl group) such as a methyl group or an ethyl group], an aryl group (such as a phenyl group). In particular, a hydrogen atom or a C _1-2 alkyl group (particularly a hydrogen atom) is preferable.

Hereinafter, an example of an α, β-unsaturated carboxylic acid ester (α, β-unsaturated carboxylic acid alkyl ester) in which the group R ³ is an alkyl group is shown. Examples of such α, β-unsaturated carboxylic acid alkyl esters include α, β-unsaturated monocarboxylic acid alkyl esters, α, β-unsaturated dicarboxylic acid alkyl esters (that is, R ⁶ -is CHR ⁸ = CR ⁷ - and one of the R ⁷ and R ^8, - (R ⁵⁾ _p-carboxylic acid alkyl ester is -COOR ^3), and the like.

Examples of the α, β-unsaturated monocarboxylic acid alkyl ester include, for example, acrylic acid alkyl esters (C _1-6 alkyl esters such as methyl acrylate, ethyl acrylate, and t-butyl acrylate, particularly t-butyl acrylate). ), Β-C _1-4 alkyl acrylic acid C such as alkyl ester of crotonic acid [Crotonic acid alkyl ester (Crotonic acid C _1-6 alkyl ester such as methyl crotonic acid, ethyl crotonic acid, t-butyl crotonic acid)] _1-6 alkyl ester (especially β-C _1-4 alkyl acrylic acid t-butyl ester)], β-cycloalkyl acrylic ester [cyclohexyl acrylic ester (methyl 3-cyclohexyl acrylate, 3-cyclohexyl acrylic acid) β-C _5-8 cycloalkylacrylic acid C ₁ such as t-butyl) _-6 alkyl esters (especially β-C _5-8 cycloalkylacrylic acid t-butyl ester), etc.], β-aryl acrylate esters [alkyl cinnamate (methyl cinnamate, ethyl cinnamate, cinnamon) Β-C _6-10 arylacrylic acid C _1-6 alkyl ester (especially β-C _6-10 aryl acrylic acid t-butyl ester) of cinnamic acid C _1-6 alkyl ester such as t-butyl acid A compound in which R ⁷ is a hydrogen atom; α-alkyl acrylate ester [methacrylic acid alkyl ester (methacrylic acid C _1-6 alkyl ester such as methyl methacrylate, ethyl methacrylate, t-butyl methacrylate, etc.] in particular, butyl t- methacrylate), alpha-C _1-4 a, such as those α- ethyl acrylate alkyl esters corresponding to methacrylic acid esters Kill acrylate C _1-6 alkyl ester (especially, alpha-C _1-4 alkyl acrylate t- butyl ester), etc.], beta-position is a hydrocarbon group α- acrylic acid alkyl ester [tiglic acid alkyl ester (tiglic Iglylic acid C _1-6 alkyl esters such as t-butyl acid) and α, β-diC _1-4 alkyl acrylic acid C _1- such as α-ethylcrotonic acid alkyl ester corresponding to these tiglic acid alkyl esters. Examples include compounds in which R ⁷ is an alkyl group, such as ₆ alkyl esters (particularly, α, β-diC _1-4 alkylacrylic acid t-butyl ester).

α, β-unsaturated dicarboxylic acid alkyl ester (compound in which R ³ is an alkyl group in the above formula (4a) or (4b)) includes di-t-butyl maleate, di-t-butyl fumarate, citracone Has substituents such as di-t-butyl acid, di-t-butyl mesaconate, di-t-butyl phenylmaleate, di-t-butyl itaconate (alkyl groups such as methyl groups, aryl groups such as phenyl groups, etc.) Examples thereof include dialkyl esters (particularly di-C _1-4 alkyl esters) of α, β-unsaturated C _4-20 aliphatic dicarboxylic acids (preferably unsaturated C _4-14 aliphatic dicarboxylic acids and the like). You can do it.

The α, β-unsaturated carboxylic acid ester (ii) may be synthesized by a conventional method as necessary. For example, α, β-unsaturated carboxylic acid ester (ii) can be converted into the group R ³ using (a) the corresponding α, β-unsaturated carboxylic acid or acid halide (chloride, bromide, etc.). Correspondingly, may be esterified, by using the (b) different α in R ^3, beta-unsaturated carboxylic acid ester (e.g. methyl ester), depending on the type of group R ^3, may also be transesterified (C) Depending on the type of the group R ⁸ , a corresponding halide (such as bromide) and an unsaturated carboxylic acid ester may be coupled by a Heck reaction for synthesis.

Further, if possible, a fluorene derivative may be produced using a carboxylic acid corresponding to the compound represented by the formula (4) (a compound in which R ³ is a hydrogen atom). For example, the corresponding halogenated carboxylic acid (X—R ² —COOH) or the corresponding α, β-unsaturated carboxylic acid (CHR ⁸ ═CR ⁷ —COOH), and the fluorenes represented by the formula (3) are reacted, after generating the corresponding fluorene polycarboxylic acid, the resulting fluorene polycarboxylic acids and compounds corresponding to R ³ (R ³ -OH, etc.) and by esterification by reacting fluorene polycarboxylic Acid esters may be produced.

  The basic catalyst is not particularly limited as long as it can generate a fluorene anion (an anion of the compound represented by the formula (3)), and a conventional inorganic base or organic base can be used. Examples of inorganic bases include metal hydroxides (alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide, alkaline earth metal hydroxides such as calcium hydroxide and barium hydroxide), and the like. It is done.

  Examples of the organic base include metal alkoxides (alkali metal alkoxides such as sodium methoxide, sodium ethoxide, and t-butoxy potassium), quaternary ammonium hydroxides (tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n hydroxide). -Tetraalkylammonium hydroxide such as butylammonium, trimethylbenzylammonium hydroxide, etc.). The trimethylbenzylammonium hydroxide can also be obtained, for example, from Tokyo Chemical Industry Co., Ltd. under the trade name “Triton B” (40% methanol solution of trimethylbenzylammonium hydroxide).

  The basic catalysts may be used alone or in combination of two or more.

  The basic catalyst may be applied to the reaction in the form of a solution dissolved in a solvent (water, alcohol, etc.).

  The amount of the basic catalyst used can be adjusted according to the type of the basic catalyst, and is selected from a range of 0.001 to 10 equivalents (molar equivalent) with respect to 1 mole of fluorenes (compound of formula (3)). In general, it may be 0.001 to 8 equivalents, preferably 0.01 to 6 equivalents (for example, 0.05 to 5 equivalents), more preferably about 0.1 to 5 equivalents.

  Moreover, the usage-amount of the carboxylic acid ester represented by the said Formula (4) is 2-10 mol with respect to 1 mol of fluorenes represented by the said Formula (3), Preferably it is 2-5 mol, More preferably May be about 2.1 to 3.5 mol (eg, 2.1 to 3 mol).

  The formation reaction of fluorene polycarboxylic acid ester may be performed in the presence of a solvent. The solvent is not particularly limited as long as it is non-reactive with the basic catalyst and can dissolve fluorenes (and the compound represented by the formula (4)), and can be used in a wide range. Typical solvents include ether solvents (dialkyl ethers such as diethyl ether, cyclic ethers such as tetrahydrofuran and 1,4-dioxane), halogenated solvents (halogenation such as methylene chloride, chloroform and carbon tetrachloride). Hydrocarbons), aromatic solvents (aromatic hydrocarbons such as benzene, toluene and xylene, anisole and the like), amides (dimethylformamide and the like), and the like. The solvents may be used alone or in combination of two or more.

  If a protic solvent (water, alcohol, etc.) is present in the reaction system (in the solvent), the activity of the intermediate fluorene anion may be lost. May be used in the reaction.

  The amount of the solvent used is such that at least the fluorenes (compound of the above formula (3)) can be dissolved, and for example, 1 to 20 parts by weight, preferably 1.5 to 15 parts by weight per 1 part by weight of the fluorenes More preferably, it may be about 2 to 10 parts by weight.

  Although the reaction can be carried out at a temperature up to the boiling point of the solvent, since the fluorene anion is unstable to heat, it is usually carried out at -10 ° C to 60 ° C, preferably at about 0 to 50 ° C. Many. Moreover, reaction time can be adjusted according to the kind of raw material, reaction temperature, the density | concentration in a solvent, etc., for example, 30 minutes-48 hours, Usually, 1 to 24 hours, Preferably it is about 1 to 10 hours.

  The reaction may be performed with stirring, may be performed in air or in an inert atmosphere (nitrogen, rare gas, etc.), or may be performed at normal pressure or under pressure.

  In a typical method for producing a fluorene polycarboxylic acid ester, the fluorenes represented by the formula (3) and a solvent are put into a reactor, and a basic catalyst is dropped gently (slowly) while stirring the reactor. Thus, a fluorene anion is generated, and subsequently, the compound represented by the formula (4) (halogenated carboxylic acid ester (i) or unsaturated compound (ii)) is dropped and reacted with the fluorene anion.

In the formula (1), the fluorene derivative in which at least one of the R ^{3a to} R ^3e is a hydrogen atom is, for example, a group R ³ (carboxyl) introduced by a carboxylic acid ester represented by the formula (4). Can be obtained by deprotection by a conventional method (for example, a method in which a fluorene polycarboxylic acid ester is produced by the above method and then hydrolyzed with a conventional base or acid). . Deprotection may be performed by isolating the fluorene polycarboxylic acid ester, or may be performed as it is in the reaction system after the production of the fluorene polycarboxylic acid ester.

  The produced fluorene derivative (especially fluorene polycarboxylic acid ester) is separated from conventional methods such as filtration, concentration, extraction, crystallization, recrystallization, column chromatography, etc., or a combination of these. Can be separated and purified. For example, after completion of the reaction, an acidic solution (an acidic aqueous solution such as dilute hydrochloric acid aqueous solution) is added to neutralize, and an organic solvent (toluene or the like) is added and extracted as necessary to extract a fluorene derivative (fluorene polycarboxylic acid). Ester) may be isolated. Moreover, you may refine | purify the produced | generated fluorene derivative (fluorene polycarboxylic acid ester) by recrystallization and / or column chromatography as needed.

The use of the fluorene derivative of the present invention is not particularly limited. In particular, in the formula (1), at least one of R ^{3a to} R ^3e is a protecting group for the carboxyl group (particularly, the carboxyl group is eliminated by the action of an acid). A fluorene derivative (that is, a fluorene polycarboxylic acid ester) that is a formable hydrophobic protecting group) is suitable as an additive constituting a photosensitive resin composition (particularly a resist composition). That is, the fluorene derivative (fluorene polycarboxylic acid ester) has high hydrophobicity due to the fluorene skeleton (and hydrophobic protective group), but is used in combination with a photosensitizer (such as a photoacid generator). Protective groups are eliminated (deprotected) due to light irradiation (particularly in association with photosensitizers by light irradiation), producing fluorene polycarboxylic acid with excellent heat resistance and a highly hydrophilic carboxyl group Is possible. Therefore, when applied to resists (especially positive resists), hydrophilic regions are formed in the exposed areas, and the dissolution of the resist film is remarkably promoted. In the unexposed areas, the action of the fluorene skeleton (and the hydrophobic protective group). As a result, the affinity with the base resin can be increased and dissolution can be remarkably suppressed, and the difference in dissolution rate between the exposed portion and the unexposed portion can be greatly increased. Further, by protecting the carboxyl group with a hydrophobic protecting group, the solubility in the unexposed area can be greatly suppressed, and the swelling of the resist accompanying development can be suppressed, and the resolution can be improved to a high degree. The removal of the protecting group is often caused by acid catalysis in connection with the photosensitizer. As such an acid, it is advantageous to use an acid generated by light irradiation (particularly an acid generated from a photoacid generator).

[Photosensitive resin composition]
The photosensitive resin composition (or resist composition) can be composed of the fluorene derivative (fluorene polycarboxylic acid ester), a photosensitive agent, and a base resin (oligomer or polymer). The photosensitive resin composition may be developable with an organic solvent (alcohol or the like), but it is usually preferable that the photosensitive resin composition be developable with water or alkali. In the photosensitive resin composition, the fluorene derivatives may be used alone or in combination of two or more.

  Examples of the photosensitizer combined with the fluorene derivative include conventional photosensitizers or photosensitizers used for positive resists, such as diazonium salts (diazonium salts, tetrazonium salts, polyazonium salts, etc.), quinonediazides (diazobenzoquinone derivatives, diazo). Naphthoquinone derivatives, etc.), photoacid generators, dissolution inhibitors and the like can be selected.

Examples of the photoacid generator include the following compounds. For reference, the trade name of Midori Chemical Co., Ltd. is described in parentheses. Sulfonium salt derivatives [sulfonic acid esters, for example, arylalkane sulfonates such as 1,2,3-tri (methylsulfonyloxy) benzene (especially C _6-10 aryl C _1-2 alkane sulfonate); 2,6-dinitrobenzyltoluene Arylbenzene sulfonates such as sulfonate and benzoin tosylate (especially C _6-10 aryl toluene sulfonate _optionally having benzoyl group); Aralkylbenzene sulfonates such as 2-benzoyl-2-hydroxy-2-phenylethyl toluene sulfonate (especially optionally having benzoyl C _6-10 aryl -C _1-4 alkyl toluenesulfonate); disulfonic such as diphenyl sulfone; Lewis acid salt (triphenylsulfonium hexafluorophosphate (TPS-1 2), triphenylsulfonium hexafluoroantimony (TPS-103), 4- (phenylthio) phenyldiphenylsulfonium hexafluoroantimony (DTS-103), 4-methoxyphenyldiphenylsulfonium hexafluoroantimony (MDS-103), triphenylsulfonium Triarylsulfonium salts (particularly triphenylsulfonium salts) such as methanesulfonyl, triphenylsulfonium trifluoromethanesulfonyl (TPS-105), triphenylsulfonium nonafluorobutanesulfonyl (TPS-109), etc.], phosphonium salt derivatives, diaryl Halonium salt derivatives [diaryliodonium salts (diphenyliodonium hexafluorophosphate, 4,4′-di (t -Butylphenyl) iodonium hexafluorophosphate (BBI-102), 4,4'-di (t-butylphenyl) iodonium hexafluoroantimonate (BBI-103), 4,4'-di (t-butylphenyl) iodonium Tetrafluoroborate (BBI-101), 4,4′-di (t-butylphenyl) iodonium trifluoromethanesulfonate (BBI-105), 4,4′-di (t-butylphenyl) iodonium camphorsulfonate (BBI-106) ), Lewis acid salts such as diphenyliodonium trifluoromethanesulfonate (DPI-105), 4-methoxyphenyl phenyliodonium trifluoromethanesulfonate (DPI-105), etc.], diazonium salt derivatives (p-nitrofe) Lewis acid salts such as rudiazonium hexafluorophosphate), diazomethane derivatives, triazine derivatives [1-methoxy-4- (3,5-di (trichloromethyl) triazinyl) benzene (TAZ-104), 1-methoxy-4- Haloalkyltriazinylaryl such as (3,5-di (trichloromethyl) triazinyl) naphthalene (TAZ-106), 1-methoxy-4- [2- (3,5-ditrichloromethyltriazinyl) ethenyl] benzene (TAZ-110), 1,2-dimethoxy-4- [2- (3,5-ditrichloromethyltriazinyl) ethenyl] benzene (TAZ-113), 1-methoxy-2- [2- (3 Haloalkyltri, such as 5-ditrichloromethyltriazinyl) ethenyl] benzene (TAZ-118) Dinyalkenyl aryl, etc.], imidyl sulfonate derivatives [succinimidyl camphor sulfonate (SI-106), succinimidyl phenyl sulfonate (SI-100), succinimidyl toluyl sulfonate (SI-101), succinimidyl trifluoromethyl sulfonate (SI-105), Phthalimidyl trifluorosulfonate (PI-105), naphthalimidyl camphorsulfonate (NAI-106), naphthalimidyl methanesulfonate (NAI-100), naphthalimidyl trifluoromethanesulfonate (NAI-105), naphthalimidyl toluylsulfonate (NAI-101), norbornene imidyl Trifluoromethanesulfonate (NDI-105) etc.] Kill. In addition, sulfone derivatives [for example, compounds having —SO ₂ —C (═N) — units such as trade names “DAM-101”, “DAM-102”, “DAM-105”, “DAM-201”; And a compound having a —CH ₂ —SO ₂ — unit, such as “PAI-101” and a compound having a ═N—O—SO ₂ — unit, etc.]. In particular, Lewis acid salts (Lewis acid salts such as phosphonium salts) are preferable.

  In particular, the photoacid generator, the fluorene derivative (fluorene polycarboxylic acid ester) that is deprotected by an acid generated by light irradiation from the acid generator to generate a carboxyl group, and a base resin (in particular, the acid The photosensitive resin composition in which the protective group is removed and the base resin becomes alkali-soluble is useful as a chemically amplified resist.

(Base resin)
Examples of the base resin include a hydroxyl group-containing polymer [polyvinyl acetal, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinyl phenol resin, novolac resin (phenol novolac resin), etc.], carboxyl group-containing polymer [polymerizable unsaturated]. Homo or copolymers containing carboxylic acid (such as (meth) acrylic acid, maleic anhydride, itaconic acid)], ester group-containing polymer [carboxylic acid vinyl ester (such as vinyl acetate), (meth) acrylic acid ester (methacrylic acid) Monomers such as methyl acid) or copolymers (polyvinyl acetate, ethylene-vinyl acetate copolymer, (meth) acrylic resin, etc.), polyesters, etc.], polymers having an ether group [polyalkylene oxide , Polyoxyalkylene Recall, polyvinyl ether resin, silicon resin, etc.], carbonate group-containing polymer, polymer having amide group or substituted amide group [polyvinyl pyrrolidone, polyurethane polymer, polyurea, nylon or polyamide polymer (lactam component, dicarboxylic acid) (Polyamides using components and diamine components); poly (meth) acrylamide polymers; polyamino acids; polymers having burette bonds; polymers having allophanate bonds; proteins such as gelatin], polymers having nitrile groups (acrylonitrile) Polymers), polymers having glycidyl groups (epoxy resins, glycidyl (meth) acrylate homo- or copolymers, etc.), halogen-containing polymers (polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, vinyl chloride) Emissions-based polymers, such as chlorinated polypropylene), a polymer having a non-aromatic ring group (e.g., (meth) monomers having C _5-8 cycloalkyl groups such as cyclohexyl acrylate polymer; (meth) norbornyl acrylate, (Meth) acrylic acid adamantyl cross-linked cyclic polymers such as C _7-20 aliphatic hydrocarbon cyclic groups), polymerizable oligomers or polymers ((meth) acryloyl groups, allyl groups, vinyl groups, cinnamoyl groups, etc.) An oligomer or a polymer having a polymerizable group of These base resins may be used alone or in combination of two or more.

  Among these base resins, typical base resins constituting positive resists are desorbed novolak resins (phenol novolac resin, cresol novolac resin, etc.) and hydrophilic groups (hydroxyl group and / or carboxyl group, etc.). Resins protected with possible protecting groups are included. Examples of the base resin constituting the negative resist include the polymer having a glycidyl group and a polyvinylphenol resin.

  In the present invention, as the base resin, a base resin for constituting a positive photosensitive resin composition (positive resist) can be suitably used.

As the novolak resin, an alkali-soluble novolak resin is usually used, and when used as a resist for semiconductor production, a conventional novolak resin used in the resist field can be used. The novolak resin can be obtained by condensing phenols having at least one phenolic hydroxyl group in the molecule with aldehydes in the presence of an acid catalyst. Examples of phenols include phenol, o-, m- or p-cresol, 2,5-, 3,5- or 3,4-xylenol, 2,3,5-trimethylphenol, ethylphenol, propylphenol, Examples thereof include butylphenol, C _1-4 alkylphenols of 2-t-butyl-5-methylphenol, dihydroxybenzene, and naphthols. Aldehydes include aliphatic aldehydes such as formaldehyde, acetaldehyde and glyoxal, and aromatic aldehydes such as benzaldehyde and salicylaldehyde.

  Phenols can be used alone or in combination of two or more, and aldehydes can be used alone or in combination of two or more. Examples of the acid catalyst include inorganic acids (such as hydrochloric acid, sulfuric acid, and phosphoric acid), organic acids (such as oxalic acid, acetic acid, and p-toluenesulfonic acid), and organic acid salts (such as divalent metal salts such as zinc acetate). It is done. The condensation reaction can be performed in a conventional manner, for example, at a temperature of about 60 to 120 ° C. for about 2 to 30 hours. The reaction may be performed in bulk or in a suitable solvent.

  The base resin (base resin constituting the positive resist) is preferably composed of a resin capable of generating a hydrophilic group by the action of an acid. Such a base resin has a hydrophilic group (in particular, a hydrophilic group selected from a hydroxyl group and a carboxyl group) having a hydrophilic group that can be protected by a protecting group that can be removed by the action of an acid. It can be composed of a monomer alone or a copolymer (a copolymer with a copolymerizable monomer).

Among the monomers having a hydrophilic group, examples of the monomer having a hydroxyl group include vinylphenol monomers (such as vinylphenol); allyl alcohol; hydroxyalkyl (meth) acrylate (hydroxyethyl (meth) acrylate) , Hydroxypropyl (meth) acrylate, hydroxy C _2-6 (meth) acrylate such as 4-hydroxybutyl (meth) acrylate); (poly) oxy C _2-4 alkylene glycol mono (such as diethylene glycol mono (meth) acrylate) A compound having a monocyclic alicyclic group [hydroxycycloalkyl (meth) acrylate ( _{hydroxyC 3-8} cycloalkyl (meth) acrylate such as hydroxycyclohexyl (meth) acrylate)], hydroxyoxacycloal A (meth) acrylate having a monocyclic aliphatic group such as a killed (meth) acrylate]; a compound having a crosslinked cyclic aliphatic hydrocarbon group [a (meth) acrylate having a crosslinked cyclic aliphatic hydrocarbon group (hydroxy Decalinyl (meth) acrylate, hydroxybornyl (meth) acrylate, hydroxynorbornyl (meth) acrylate, hydroxybiantyl to tetra C _3-8 cycloalkyl (meth) acrylate, etc.), And norbornene derivatives having a hydroxyl group [hydroxynorbornene, hydroxyalkyl-norbornene (hydroxy _C1-4 alkyl-norbornene such as hydroxymethyl-norbornene, hydroxyethyl-norbornene, etc.)] and the like. Monomers having a carboxyl group include unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, vinylbenzoic acid; monocyclic aliphatic groups Compound [Carboxy C _5-8 cycloalkyl (meth) acrylate such as carboxycyclohexyl (meth) acrylate and the like]; Carboxy (meth) acrylate having a bridged cyclic aliphatic hydrocarbon group (for example, carboxydecalinyl (meth) acrylate) Carboxybi to tetra C _3-8 cycloalkyl (meth) acrylate, such as carboxynorbornyl (meth) acrylate, carboxymethyl-norbornyl (meth) acrylate, carboxybornyl (meth) acrylate, carboxyadamantyl (meth) acrylate, etc. )etc It is below. These monomers having a hydrophilic group can be used alone or in combination of two or more.

As the copolymerizable monomer to be combined with the monomer having a hydrophilic group, a conventional copolymerizable monomer such as a (meth) acrylic monomer [for example, methyl (meth) acrylate, ethyl (meth) ) Acrylate, alkyl (meth) acrylate such as butyl (meth) acrylate (C _1-10 alkyl (meth) acrylate); compound having a monocyclic alicyclic group [cycloalkyl (meth) acrylate (cyclohexyl (meth) acrylate) C _3-8 cycloalkyl (meth) acrylate), (meth) acrylate having a monocyclic alicyclic group such as oxacycloalkyl (meth) acrylate, etc.]; decalinyl (meth) acrylate, norbornyl (meth) acrylate , Bornyl (meth) acrylate, adamantyl (meth) acrylate, etc. Aliphatic having a hydrocarbon group (meth) acrylate (bi or tetracyclic C _3-8 alkyl (meth) acrylate); hydroxy C _2-6 alkyl (meth) acrylates such as hydroxyethyl (meth) acrylate; glycidyl (meth) acrylate Epoxy group-containing (meth) acrylates such as (meth) acrylonitrile and the like]; Imide monomers [eg, N—C _1-4 alkylmaleimides such as maleimide, N-methylmaleimide, N-ethylmaleimide, N-phenyl] N—C _6-10 arylmaleimide such as maleimide]; aromatic vinyl monomers (styrene monomers) such as styrene, α-methylstyrene, pt-butylstyrene, vinyltoluene; vinyl methyl ether , Vinyl ether monomers such as vinyl ethyl ether; vinyl acetate, Such as fatty acid vinyl SL monomers such as propionic acid vinyl, and the like.

  These copolymerizable monomers can be used alone or in combination of two or more. In the copolymer with the copolymerizable monomer, the proportion of the monomer having a hydrophilic group is 10 to 100% by weight, preferably 25 to 80% by weight, further based on the total amount of the monomer. Preferably, it may be about 30 to 70% by weight.

The protecting group for protecting the hydrophilic group is not particularly limited. For example, a protecting group for hydroxyl group [acyl group (C _1-6 alkyl-carbonyl group such as t-butylcarbonyl group, 2,2-dimethylpropionyl group, etc.) Etc.), alkoxycarbonyl groups (C _1-6 alkoxycarbonyl groups such as t-butoxycarbonyl group (t-BOC group)), 5- or 6-membered oxacycloalkyl groups (such as tetrahydropyranyl group), and substituents An optionally substituted bi- or tricycloalkyl group (a norbornyl group optionally having a substituent such as a 2-norbornyl group, a 2-methyl-2-norbornyl group, a 2-adamantyl group, a 2-methyl-2- An adamantyl group which may have a substituent such as an adamantyl group), an alkoxyalkyl group (1-methoxyethyl group, 1-ethoxy group). Ethyl group, 1-ethoxypropyl group, 1-C _1-6 alkoxy -C _1-6 alkyl group (particularly C _1-4 alkoxy -C _1-4 alkyl group), such as methoxy isopropyl group, etc.), C _1-4 Alkylsilyl group etc.], protecting group for carboxyl group [alkyl group (C _1-4 alkyl group such as t-butyl group), bi- or tricycloalkyl group optionally having substituent (bridged alicyclic ring) Substituents such as a norbornyl group, 2-adamantyl group, 2-methyl-2-adamantyl group and the like which may have a substituent such as an aromatic hydrocarbon group, for example, 2-norbornyl group, 2-methyl-2-norbornyl group An adamantyl group which may have a group), a 5- or 6-membered oxacycloalkyl group which may have a substituent, a lactone ring group which may have a substituent, a carbamoyl group or an N-substituted group. Carbamoyl group Etc.].

  In the hydrophilic group, the ratio of protection by the protecting group depends on the ratio of the protecting group in the base resin, but can be selected, for example, from a range of about 0.05 to 1 mol with respect to 1 mol of the hydrophilic group. 0.1 to 0.8 mol, preferably 0.2 to 0.6 mol, more preferably about 0.3 to 0.5 mol.

  The resin protected with the protecting group may be obtained by polymerizing a monomer having a hydrophilic group previously protected with a protecting group, or obtained by polymerizing a monomer having a hydrophilic group. You may obtain by protecting the hydrophilic group of the resin with the said protecting group.

As a resin having a specific hydrophilic group corresponding to a base resin protected with a protecting group from which a hydrophilic group (hydroxyl group and / or carboxyl group) can be removed, for example, a polyvinylphenol resin (vinylphenol) Or a copolymer with a copolymerizable monomer), a hydroxyl group and / or carboxyl group-containing (meth) acrylic resin [for example, a (meth) acrylate homopolymer or copolymer, or ( A copolymer of a meth) acrylate and a copolymerizable monomer], a hydroxyl group-containing alicyclic resin {for example, a hydroxy C _3-8 cycloalkyl (meth) acrylate (such as hydroxycyclohexyl (meth) acrylate) Monomer or copolymer of a monomer having a hydroxyl group-containing monocyclic aliphatic hydrocarbon ring group such as copolymerization with a copolymerizable monomer Hydroxybi to tetra C _3-8 cycloalkyl (meth) acrylate (hydroxynorbornyl (meth) acrylate, hydroxyadamantyl (meth) acrylate, etc.), norbornene having a hydroxyl group (hydroxynorbornene, hydroxy C _{1) -4} alkyl-norbornene, etc.) such as a monomer having a hydroxyl group-containing bridged cyclic aliphatic hydrocarbon ring group or a copolymer (including a copolymer with a copolymerizable monomer)}, a carboxyl group -Containing alicyclic resin {for example, a monomer having a carboxyl group-containing monocyclic aliphatic hydrocarbon ring group such as carboxy C _3-8 cycloalkyl (meth) acrylate (such as carboxycyclohexyl (meth) acrylate) alone or Copolymer (including copolymer with copolymerizable monomer); Carboxy Bi or tetra C _3-8 cycloalkyl (meth) acrylate (carboxymethyl norbornyl (meth) acrylate, carboxy, etc. adamantyl (meth) acrylate), carboxy C _1-4 Arukirubi to tetra C _3-8 cycloalkyl (meth) acrylate Monomers or copolymers of a monomer having a carboxyl group-containing crosslinked cyclic aliphatic hydrocarbon ring group such as (including a copolymer with a copolymerizable monomer)} and the like.

  In addition, when a resin (non-aromatic resin such as (meth) acrylic resin or hydroxyl group- or carboxyl group-containing alicyclic resin) having high transparency with respect to the exposure wavelength is used as the base resin, a short wavelength is used. In some cases, the sensitivity can be further improved with respect to exposure light. When a non-aromatic photosensitive resin composition is used, an exposure source with a shorter wavelength can be used and a finer pattern may be formed.

  The weight average molecular weight of the base resin is about 6,000 to 50,000, preferably about 7,000 to 30,000, and more preferably about 7,000 to 20,000.

  Preferred resists (positive resists) include a combination of a resin that generates a hydrophilic group by deprotection (particularly, deprotection by the catalytic action of an acid generated from an acid generator) and a photosensitive agent (particularly a photoacid generator). Is included.

(Ratio of each component)
The ratio (weight ratio) between the fluorene derivative (fluorene polycarboxylic acid ester) and the photosensitizer (photo acid generator, etc.) can be selected from a wide range of the former / the latter = 0.01 / 1 to 100/1, Usually, it is about 0.1 / 1 to 75/1, preferably 1/1 to 50/1, more preferably about 1.5 / 1 to 20/1 (for example, 2/1 to 15/1). Good.

  In the photosensitive resin composition (positive photosensitive resin composition or positive resist), the amount of the photosensitive agent used is, for example, 0.1 to 50 parts by weight, preferably 1 to 30 parts by weight based on 100 parts by weight of the base resin. It can be selected from the range of about 1 part by weight, more preferably about 1 to 20 parts by weight (particularly 2 to 10 parts by weight).

  The amount of the fluorene derivative (fluorene polycarboxylic acid ester) used is 0.01 to 50 parts by weight, preferably 0.05 to 30 parts by weight, more preferably 100 parts by weight of the base resin (in terms of solid content). It may be about 0.1 to 20 parts by weight, particularly about 0.5 to 10 parts by weight. The fluorene derivative (fluorene polycarboxylic acid ester) is 0.05 to 100 parts by weight, preferably 0.1 to 30 parts by weight, based on 100 parts by weight of the total amount of the base resin and the photosensitizer (in terms of solid content). Preferably it may be about 0.5 to 20 parts by weight, particularly about 1 to 10 parts by weight.

  If necessary, the photosensitive resin composition may contain various additives such as stabilizers such as antioxidants, plasticizers, surfactants, dissolution accelerators, and colorants such as dyes and pigments. Furthermore, in order to improve workability such as coating properties, the photosensitive resin composition is provided with a solvent [hydrocarbons, halogenated hydrocarbons, alcohols (methanol, ethanol, isopropanol, etc.), ketones (acetone, cyclohexanone, etc.). ), Esters (ethyl acetate, ethyl lactate, etc.), ethers, cellosolves (methyl cellosolve, ethyl cellosolve, butyl cellosolve, etc.), carbitols, glycol ether esters (cellosolve acetate, propylene glycol monomethyl ether acetate (PGMEA, etc.), etc.) (Poly) oxyalkylene glycol alkyl ether acetate, etc.).

  The photosensitive resin composition is prepared by a conventional method, for example, a photosensitive resin [a photosensitive resin composition composed of a base resin (polymer or oligomer) and a photosensitive agent] and a fluorene derivative (fluorene polycarboxylic acid ester). It can be prepared by mixing. The photosensitive resin composition usually contains a solvent [for example, lactic acid ester such as ethyl lactate; (poly) oxyalkylene glycol alkyl ether acetate such as propylene glycol methyl ether acetate (such as PGMEA)]. The amount of the solvent used is not particularly limited, and is, for example, 0.1 to 50 parts by weight, preferably 1 to 40 parts by weight, and more preferably about 5 to 30 parts by weight with respect to 1 part by weight of the photosensitive resin. .

[Photosensitive layer]
A photosensitive layer can be formed by applying (coating or coating) the photosensitive resin composition to a substrate (substrate). The substrate (substrate) can be appropriately selected from metals (aluminum, etc.), glass, ceramics (alumina, copper-doped alumina, tungsten silicate, etc.), plastics, etc., depending on the pattern characteristics and applications. Semiconductors such as silicon wafers It may be a substrate.

  The substrate may be surface-treated in advance in order to improve the adhesion with the photosensitive layer depending on the application. For the surface treatment, for example, surface treatment with the silane coupling agent (hydrolyzable polymerizable silane coupling agent having a polymerizable group, etc.), anchor coating agent or base agent (polyvinyl acetal, acrylic resin, vinyl acetate type) Resin, epoxy resin, urethane resin, etc.), or a coating treatment with a mixture of these base materials and inorganic fine particles.

  In addition, after apply | coating the photosensitive resin composition to a board | substrate, you may evaporate a solvent by drying. The removal of the solvent may be performed by, for example, soft baking (pre-baking) using a heating means such as a hot plate.

  The photosensitive layer made of the photosensitive resin composition of the present invention may be formed on at least the surface of the resist layer. The structure of the photosensitive layer can be selected according to a pattern formation process, a circuit structure, and the like, and may be a single layer structure or a multilayer structure (or a laminated structure or a composite structure).

  The thickness of the photosensitive layer is not particularly limited, and can be selected from the range of, for example, 0.01 to 10 μm, preferably 0.05 to 5 μm, preferably about 0.08 to 2 μm, and usually 0.05 to 1 μm (for example, 0.1 to 0.7 μm).

  The photosensitive layer can be formed by a conventional coating method such as a spin coating method, a dipping method, or a casting method. If necessary, the photosensitive layer can be formed by drying to remove the solvent.

[Pattern formation method]
A pattern (particularly a fine pattern) can be formed by using a conventional lithography technique that combines exposure, development, etching, and the like.

  For example, a pattern can be formed by applying the photosensitive resin composition prepared by the above-described method onto a substrate to form a photosensitive layer, exposing it, heat-treating it as necessary, and further developing it. In particular, when a chemically amplified photosensitive resin is used, it is preferable to perform heat treatment (post-exposure baking (post-exposure baking, PEB)) after the exposure in order to efficiently diffuse the acid generated by the exposure. In addition, after patterning by development, etching treatment may be performed by plasma treatment (oxygen plasma or the like).

The photosensitive layer can be exposed by a conventional method, for example, by irradiating a pattern with light or exposing it to light through a predetermined mask. As the light beam, various light beams (active light beams) depending on the photosensitive characteristics of the photosensitive resin composition, the fineness of the pattern, the type of the base resin, etc., for example, light beams such as halogen lamps, high pressure mercury lamps, UV lamps; (436 nm), i-line (365 nm), excimer laser (for example, XeCl (308 nm), KrF (248 nm), KrCl (222 nm), ArF (193 nm), ArCl (172 nm), F ₂ (157 nm), etc.), electron beam , EB rays, EUV rays (13 nm), X-rays and the like can be used, and may be a single wavelength or a composite wavelength. In particular, excimer lasers such as KrF (248 nm), ArF (193 nm), and F ₂ (157 nm), light rays having a wavelength of about 10 to 300 nm such as X-rays, EB rays, and EUV rays (13 nm) can be advantageously used.

  The exposure energy can be selected according to the photosensitive characteristics (solubility, etc.) of the photosensitive resin composition. The exposure time can be selected from the range of usually 0.005 seconds to 10 minutes, preferably about 0.01 seconds to 1 minute.

  The temperature of heating (pre-baking and PEB) is 50 to 150 ° C., preferably 60 to 150 ° C., more preferably about 70 to 150 ° C., and the heating time is 30 seconds to 5 minutes, preferably about 1 to 2 minutes. It is.

  After pattern exposure, a pattern with high resolution can be formed by developing by a conventional method. Various developing solutions (water, aqueous alkali solution, etc.) can be used for development according to the type of the photosensitive resin composition. A preferred developer is water or an alkali developer, and if necessary, a small amount of an organic solvent (for example, alcohols such as methanol, ethanol and isopropanol, ketones such as acetone, ethers such as dioxane and tetrahydrofuran, cellosolves) , Hydrophilic or water-soluble solvents such as cellosolve acetate) and surfactants. The development method is not particularly limited, and for example, a paddle (meniscus) method, a dip method, a spray method, or the like can be adopted.

  The coating film (photosensitive layer) may be heated or cured at an appropriate temperature in an appropriate process from the application to the development of the photosensitive resin composition, not limited to the prebaking and PEB. For example, heat treatment may be performed as necessary after development.

  The fluorene derivative (fluorene polycarboxylic acid ester, in particular, fluorene tetracarboxylic acid ester) of the present invention is useful for application to a resist composition and the like, and is a photosensitivity composed of the fluorene derivative (fluorene polycarboxylic acid ester). The resin composition can be used in various applications such as circuit forming materials (resist for semiconductor production, printed wiring boards, etc.), image forming materials (printing plate materials, relief images, etc.) and the like. In particular, since high sensitivity and resolution can be obtained, it can be advantageously used as a resist for semiconductor manufacturing.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Example 1
200 ml of 1,4-dioxane and 33.2 g (0.2 mol) of fluorene were placed in a reactor, and the fluorene was dissolved by stirring. After cooling to 10 ° C., trimethylbenzylammonium hydroxide (Tokyo Kasei ( 3.0 ml of 40 wt% ethanol solution of Triton B40) manufactured by the same company was added dropwise and stirred for 30 minutes. Next, 100.3 g (0.44 mol) of di-t-butyl maleate was added dropwise and stirred for about 3 hours. After completion of the reaction, 200 ml of toluene and 50 ml of 0.5N hydrochloric acid were added for washing. After removing the aqueous layer, the organic layer was washed 3 times with 30 ml of distilled water. By distilling off the solvent, 7,4.3 g of 9,9-bis (di-t-butyl succinate) fluorene {or 9,9-bis [1,2-di (t-butoxycarbonyl) ethyl] -fluorene} was obtained. (Yield 90%) was obtained. Furthermore, after dissolving in 300 ml of isopropyl alcohol at 70 ° C. and recrystallization by cooling to 10 ° C., 104.5 g (yield 84%, purity 98.8%) of 9,9-bis (succinic acid) Acid di-t-butyl) fluorene could be obtained. The ¹ H-NMR analysis result of the obtained 9,9-bis (di-t-butyl succinate) fluorene is shown below.

¹ H-NMR (CDCl ₃ ) ppm: 1.1 (s, CH ₃ , 36H), 2.5 (d, CH ₂ , 4H), 2.8 (t, CH, 2H), 7.3-7 .5 (m, benzene ring, 4H), 7.6 (d, benzene ring, 2H), 7.8 (d, benzene ring, 2H).

(Example 2)
200 ml of dimethylformamide and 33.2 g (0.2 mol) of fluorene were placed in a reactor, and the fluorene was dissolved by stirring. After cooling to 10 ° C., 67.3 g (0.6 mol of potassium tert-butoxy) ) And stirred for 30 minutes. Next, 136.8 g (0.6 mol) of di-t-butyl maleate was added dropwise and stirred for about 3 hours. After completion of the reaction, 200 ml of toluene and 50 ml of distilled water were added and washed. After removing the aqueous layer, the organic layer was washed 3 times with 50 ml of distilled water. By distilling off the solvent, 99.5 g (yield 80%) of 9,9-bis (di-t-butyl succinate) fluorene was obtained. Further, after being dissolved in 270 ml of isopropyl alcohol at 70 ° C. and recrystallized by cooling to 10 ° C., 93.3 g (yield 75%, purity 98.6%) of 9,9-bis (succinic acid) was obtained. Acid di-t-butyl) fluorene could be obtained. The ¹ H-NMR analysis result of the obtained 9,9-bis (di-t-butyl succinate) fluorene is shown below.

¹ H-NMR (CDCl ₃ ) ppm: 1.1 (s, CH ₃ , 36H), 2.5 (d, CH ₂ , 4H), 2.8 (t, CH, 2H), 7.3-7 .5 (m, benzene ring, 4H), 7.6 (d, benzene ring, 2H), 7.8 (d, benzene ring, 2H).

(Example 3)
200 ml of dimethylformamide and 33.2 g (0.2 mol) of fluorene were placed in the reactor, and the fluorene was dissolved by stirring. After cooling to 10 ° C., 32.4 g (0.6 mol) of sodium methylate was cooled. And stirred for 30 minutes. Next, 136.8 g (0.6 mol) of di-t-butyl maleate was added dropwise and stirred for about 3 hours. After completion of the reaction, 200 ml of toluene and 50 ml of distilled water were added and washed. After removing the aqueous layer, the organic layer was washed 3 times with 50 ml of distilled water. By distilling off the solvent, 10,5.7 g (yield 85%) of 9,9-bis (di-t-butyl succinate) fluorene was obtained. Furthermore, after dissolving in 300 ml of isopropyl alcohol at 70 ° C. and recrystallization by cooling to 10 ° C., 99.5 g (yield 80%, purity 99.0%) of 9,9-bis (succinic acid) was obtained. Acid di-t-butyl) fluorene could be obtained. The ¹ H-NMR analysis result of the obtained 9,9-bis (di-t-butyl succinate) fluorene is shown below.

¹ H-NMR (CDCl ₃ ) ppm: 1.1 (s, CH ₃ , 36H), 2.5 (d, CH ₂ , 4H), 2.8 (t, CH, 2H), 7.3-7 .5 (m, benzene ring, 4H), 7.6 (d, benzene ring, 2H), 7.8 (d, benzene ring, 2H).

Example 4
Instead of 33.2 g (0.2 mol) of fluorene, 73.2 g (0.2 mol) of 2,7-di-t-butoxycarbonylfluorene was used and 63.4 g (0. The reaction was carried out in the same manner as in Example 1 except that 82.7 g (0.44 mol) of t-butyl acrylate was used instead of 44 mol). As a result, 2,7-di-t-butoxycarbonyl-9,9-bis (di-t-butylpropionate) fluorene {or 2,7-bis (t-butoxycarbonyl) -9,9-bis [2 -(T-Butoxycarbonyl) ethyl] fluorene} 80.9 g (yield 65%, purity 98.2%) could be obtained. The results of ¹ H-NMR analysis of the obtained 2,7-di-t-butoxycarbonyl-9,9-bis (di-t-butyl propionate) fluorene are shown below.

¹ H-NMR (CDCl ₃ ) ppm: 1.1 (s, CH ₃ , 36H), 1.4 (t, CH ₂ , 4H), 2.2 (t, CH ₂ , 4H), 7.9- 8.1 (m, benzene ring, 4H), 8.2 (s, benzene ring, 2H).

(1) Preparation of photosensitive resin To 0.5 parts by weight of a 9,000 weight average molecular weight polyvinylphenol resin in which 35 mol% of hydroxyl groups were protected with 1-ethoxyethoxy group, 37 mol% of hydroxyl groups was t. 0.5 part by weight of a polyvinylphenol resin having a weight average molecular weight of 8,500 substituted with a —BOC (tert-butoxycarbonyloxy) group was added, and 0.02 part by weight of a photoacid generator represented by the following formula (A) was added. A positive photoresist was prepared by adding and mixing 6 parts by weight of propylene glycol monomethyl ether acetate as a solvent.

(2) Preparation of photosensitive resin composition To the photosensitive resin solution obtained in the step (1), 9,9-bis (di-t-butyl succinate) fluorene obtained in Example 1 was added. Was added at a ratio shown in the following, and filtered through a fluororesin (polytetrafluoroethylene) (0.2 μm) to obtain a photosensitive resin composition. In addition, the ratio (weight part) shown in Table 1 is a ratio with respect to 1 weight part of solid content except the solvent of the said photosensitive resin solution.

(3) Performance (sensitivity, resolution) evaluation After processing the cleaned silicon wafer with hexamethyldisilazane, the photosensitive resin composition obtained in step (2) was dried using a spin coater. Was applied to 0.4 μm and heated on a hot plate at 100 ° C. for 1 minute. Next, a test mask having line-and-space patterns with different line widths using a reduction projection exposure machine (Canon, FPA-3000EX5, NA = 0.63) having an exposure wavelength of 248 nm (KrF excimer laser) Then, the exposure amount was changed in stages. The wafer was heated on a hot plate at 100 ° C. for 1 minute and then paddle developed with a 2.38 wt% tetramethylammonium hydroxide aqueous solution for 1 minute to obtain a positive pattern.

  Each characteristic of the positive pattern was evaluated as follows.

(i) Sensitivity: A line width with a line width of 0.25 μm: Space = 1: 1 was displayed with an exposure amount at which the mask dimensions corresponded. (The smaller the value, the better the sensitivity)
(ii) Resolution: Line with a line width of 0.25 μm: Space = 1: 1 is displayed with the minimum dimension that the lines are separated at an exposure amount that matches the mask dimension. (The smaller the value, the better the resolution)
The results are shown in Table 1. In Table 1, as a comparative example, the sensitivity and resolution of a photosensitive resin composition not containing 9,9-bis (di-t-butyl succinate) fluorene are also shown.

  As is clear from Table 1, the sensitivity and resolution were significantly improved by adding 9,9-bis (di-t-butyl succinate) fluorene.

Claims (4)

A fluorene derivative represented by the following formula (1).

[ Wherein, R ^2a and R ^2b represent a C _1-6 alkylene group , and R ^{3a to} R ^3d represent a C _1-4 alkyl group . ] The fluorene derivative according to claim 1, wherein all of R ^3a to R ^3d are t-butyl groups. 2,7-bis _{(C 1-4} alkoxycarbonyl) -9,9-bis _{(C 1-4} alkoxycarbonyl _{-C 1-6} alkyl) fluorene derivative according to claim 1 wherein the fluorene down. A method for producing the fluorene derivative according to claim 1, wherein in the presence of a basic catalyst, a fluorene represented by the following formula (3) and a carboxylic acid ester represented by the following formula (4): A method for producing a fluorene derivative comprising at least a step of reacting.

{In the formula, R ³ represents a C _1-4 alkyl group , R ⁶ -represents X-R ^2- (wherein R ² represents a C _1-6 alkylene group , and X represents a halogen atom ) . }