Radiation-sensitive composition, cured film, display element, and method for producing cured film

Abstract

The main purpose of the present invention is to provide: a radiation-sensitive composition capable of forming a cured film having excellent radiation sensitivity, melt fluidity resistance, relative dielectric constant, and chemical resistance; a cured film; a display element; and a method for producing a cured film. The present invention relates to a radiation-sensitive composition containing a polymer component (A), a quinonediazide compound (B), and a solvent (C), the polymer component (A) contains, in the same polymer or different polymers: at least one structural unit (I) selected from the group consisting of structural units having an acid group and structural units derived from maleimide; a structural unit (II) containing an alicyclic epoxy group; and a structural unit (III) (excluding structural units (II)) derived from a (meth) acrylic acid ester having an alicyclic structure.

Description

Technical Field

[0001] The present invention relates to a radiation-sensitive composition, a cured film, a display element, and a method for producing a cured film. Background Art

[0002] In a display element, an insulating cured film such as an interlayer insulating film or a planarizing film for insulating between wirings and a substrate or between wirings, or a partition wall is provided. Generally, such a cured film is formed by subjecting a coating film formed from a radiation-sensitive composition to exposure and development treatments and then performing a heat treatment to cause thermal curing.

[0003] As a material for forming such a cured film, a photosensitive resin composition is known, which contains: an acrylic copolymer obtained by copolymerizing an unsaturated carboxylic acid, an epoxy group-containing unsaturated compound, and an olefinic unsaturated compound in a specific ratio; a quinone diazide compound; a solvent; and a specific silane surfactant (for example, refer to Patent Document 1).

[0004] [Prior Art Documents]

[0005] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-156471 Summary of the Invention

[0007] [Problems to be Solved by the Invention]

[0008] In recent years, regarding cured films (for example, planarizing films or interlayer insulating films, etc.) used in display devices such as organic light emitting diodes (OLEDs) and liquid crystal display devices (liquid crystal displays (LCDs)), due to changes in panel or element structures, further reduction in dielectric constant has been required. In addition, in order to improve productivity, exposure sensitivity has also increased in importance.

[0009] As a method for reducing the dielectric constant of a cured film, a method of introducing a functional group having a small molar polarization into a structural element of a composition for forming a cured film is known, but depending on the type of the introduced functional group, the hydrophilicity of the composition for forming a cured film decreases, and as a result, developability and exposure sensitivity sometimes decrease. That is, in existing compositions for forming a cured film, it is difficult to balance cured film physical properties such as developability, radiation sensitivity, and chemical resistance with reduction in dielectric constant.

[0010] The present invention has been completed in view of the above problems, and a main object thereof is to provide a radiation-sensitive composition capable of forming a cured film excellent in radiation sensitivity, melt flow resistance, relative dielectric constant, and chemical resistance.

[0011] [Technical means for solving the problem]

[0012] According to the present invention, there are provided the following radiation-sensitive composition, cured film, display element, and method for producing a cured film.

[0013] In one embodiment, the present invention relates to a radiation-sensitive composition containing:

[0014] a polymer component (A);

[0015] a quinonediazide compound (B); and

[0016] a solvent (C), wherein in the radiation-sensitive composition,

[0017] the polymer component (A) contains, in the same polymer or different polymers:

[0018] at least one structural unit (I) selected from the group consisting of a structural unit having an acid group and a structural unit derived from maleimide;

[0019] a structural unit (II) containing an alicyclic epoxy group; and

[0020] a structural unit (III) derived from a (meth)acrylate having an alicyclic structure (excluding the structural unit (II)),

[0021] the structural unit (II) is 10% by mass or more based on all the structural units constituting the polymer component (A),

[0022] the structural unit (III) is 10% by mass or more based on all the structural units constituting the polymer component (A).

[0023] In another embodiment, the present invention relates to a method for producing a cured film, including:

[0024] a step of coating the radiation-sensitive composition on a substrate;

[0025] a step of removing the solvent from the coated radiation-sensitive composition;

[0026] a step of irradiating the radiation-sensitive composition from which the solvent has been removed with radiation;

[0027] a step of developing the radiation-sensitive composition irradiated with the radiation; and

[0028] a step of thermally curing the developed radiation-sensitive composition.

[0029] In still another embodiment, the present invention relates to a cured film and a display element,

[0030] The cured film is formed using the radiation-sensitive composition, and the display element includes the cured film.

[0031] [Effects of the Invention]

[0032] The radiation-sensitive composition of the present invention contains a polymer component (A), that is, a polymer component (A) containing a structural unit (II) having an alicyclic epoxy group and a structural unit (III) derived from a (meth)acrylate having an alicyclic structure in a specific amount. Thereby, while maintaining high radiation sensitivity, the glass transition temperature of the polymer can be increased. As a result, a cured film can be formed that suppresses melt flow, has a good pattern shape, can sufficiently reduce the relative dielectric constant, and has excellent chemical resistance. Detailed Embodiments

[0033] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to these embodiments.

[0034] Hereinafter, matters related to the embodiments will be described in detail. In addition, in this specification, the numerical range described using "~" means including the numerical values described before and after "~" as the lower limit value and the upper limit value. The so-called "structural unit" is a unit that mainly constitutes the main chain structure and means a unit containing two or more units at least in the main chain structure.

[0035] In this specification, "hydrocarbyl group" means including a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. The so-called "chain hydrocarbon group" means a straight-chain hydrocarbon group and a branched hydrocarbon group that do not contain a cyclic structure in the main chain and are composed only of a chain structure. Among them, the chain hydrocarbon group can be saturated or unsaturated. The so-called "alicyclic hydrocarbon group" means a hydrocarbon group that contains only an alicyclic hydrocarbon structure as the ring structure and does not contain an aromatic ring structure. Among them, the alicyclic hydrocarbon group does not need to be composed only of an alicyclic hydrocarbon structure and also includes a group having a chain structure in a part thereof. The so-called "aromatic hydrocarbon group" means a hydrocarbon group that contains an aromatic ring structure as the ring structure. Among them, the aromatic hydrocarbon group does not need to be composed only of an aromatic ring structure and may also include a chain structure or an alicyclic hydrocarbon structure in a part thereof. In addition, the ring structure of the alicyclic hydrocarbon group and the aromatic hydrocarbon group may also have a substituent containing a hydrocarbon structure. "Cyclic hydrocarbon" means including an alicyclic hydrocarbon and an aromatic hydrocarbon.

[0036] In this specification, "(meth)acryloyl group" means including "acryloyl group" and "methacryloyl group", and "(meth)acrylic group" means including "acrylic group" and "methacrylic group". "(meth)acrylate" means including "acrylate" and "methacrylate".

[0037] <Radiation-Sensitive Composition>

[0038] The radiation-sensitive composition of the present embodiment (hereinafter also referred to as "the present composition") relates to a radiation-sensitive composition containing:

[0039] Polymeric component (A);

[0040] Quinonediazide compound (B); and

[0041] Solvent (C). In the radiation-sensitive composition,

[0042] The polymeric component (A) includes, in the same polymer or different polymers:

[0043] At least one structural unit (I) selected from the group consisting of a structural unit having an acid group and a structural unit derived from maleimide;

[0044] Structural unit (II) containing an alicyclic epoxy group; and

[0045] Structural unit (III) derived from an (meth)acrylate having an alicyclic structure (excluding structural unit (II)),

[0046] Relative to all the structural units constituting the polymeric component (A), the structural unit (II) is 10% by mass or more,

[0047] Relative to all the structural units constituting the polymeric component (A), the structural unit (III) is 10% by mass or more.

[0048] Hereinafter, each component contained in the present composition and other components formulated as needed will be described. In addition, regarding each component, unless otherwise specified, one kind can be used alone, or two or more kinds can be used in combination.

[0049] <Polymeric component (A)>

[0050] The polymeric component (A) is an aggregate of polymers containing structural units (I) to (III). These structural units can be contained in the same polymer, and these structural units can also be contained in different polymers. As a whole of the polymers constituting the polymeric component (A), it is sufficient to contain structural units (I) to (III). Therefore, as long as structural units (I) to (III) are contained, the polymeric component (A) can contain one polymer or two or more polymers. The polymeric component (A) can contain structural units other than structural units (I) to (III). In addition, the polymeric component (A) may further contain a polymer having none of the structural units (I) to (III).

[0051] (Structural unit (I))

[0052] By including a polymer containing the structural unit (I) in the polymer component (A), good alkali solubility can be imparted to the polymer component. In addition, in this specification, "alkali-soluble" means soluble in an alkali aqueous solution such as a 2.38 mass% concentration aqueous solution of tetramethylammonium hydroxide.

[0053] The structural unit (I) is at least one structural unit selected from the group consisting of a structural unit (I-1) having an acid group and a structural unit (I-2) derived from maleimide.

[0054] The structural unit (I-1) is not particularly limited as long as it has an acid group. Examples of the acid group include a carboxyl group, a sulfonic acid group, a phenolic hydroxyl group, etc. Specifically, as the structural unit (I), it is preferably at least one selected from the group consisting of a structural unit having a carboxyl group, a structural unit having a phenolic hydroxyl group, and a structural unit having a sulfonic acid group, and more preferably at least one selected from the group consisting of a structural unit having a carboxyl group and a structural unit having a phenolic hydroxyl group. In addition, in this specification, "phenolic hydroxyl group" means a hydroxyl group directly bonded to an aromatic ring (for example, a benzene ring, a naphthalene ring, an anthracene ring, etc.).

[0055] The structural unit (I-1) is not particularly limited, and from the viewpoint of copolymerizability, it is preferably a structural unit derived from an unsaturated monomer having an acid group.

[0056] Regarding specific examples of the monomer providing the structural unit (I-1), as the monomer providing a structural unit having a carboxyl group, for example, (meth)acrylic acid, crotonic acid, 4-vinylbenzoic acid and other unsaturated monocarboxylic acids can be cited; maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid and other unsaturated dicarboxylic acids, etc.; as the monomer providing a structural unit having a sulfonic acid group, for example, vinyl sulfonic acid, (meth)allyl sulfonic acid, styrene sulfonic acid, (meth)acryloyloxyethyl sulfonic acid, etc. can be cited; as the monomer providing a structural unit having a phenolic hydroxyl group, for example, 4-hydroxystyrene, o-isopropenylphenol, m-isopropenylphenol, p-isopropenylphenol, (meth)acrylic acid hydroxybenzyl ester, etc. can be cited.

[0057] The structural unit (I-2) is a structural unit derived from maleimide. The so-called structural unit derived from maleimide means a structural unit derived from unsubstituted maleimide represented by the following formula.

[0058] [Chemical formula 1]

[0059]

[0060] As the structural unit (I), the structural unit (I-1) is preferred.

[0061] In the polymer component (A), from the viewpoint of imparting good solubility in an alkali developer, the content ratio (total content ratio in the case of containing a plurality of them) of the structural unit (I) is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 8% by mass or more, and particularly preferably 10% by mass or more, relative to all the structural units constituting the polymer component (A). Further, from the viewpoint of sufficiently generating a difference in solubility in an alkali developer between the exposed portion and the unexposed portion and obtaining a pattern with a good shape, the content ratio of the structural unit (I) is preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, relative to all the structural units constituting the polymer component (A).

[0062] (Structural unit (II))

[0063] By the polymer component (A) containing a polymer having the structural unit (II), a cured film having excellent melt flow resistance and chemical resistance can be formed.

[0064] The so-called alicyclic epoxy group means a group having a structure in which an epoxy group is formed by two adjacent carbon atoms and an oxygen atom constituting an alicyclic group. Examples of the alicyclic epoxy group include: 2,3-epoxycyclobutyl, 2,3-epoxycyclopentyl, 3,4-epoxycyclohexyl, 3,4-epoxytricyclo[5.2.1.0 2,6 decane-yl, 5,6-epoxytricyclo[5.2.1.0 2,6 decane-yl, 2,3-epoxytricyclo[4.2.1.0 2,5 nonane-yl, etc. Among these, 3,4-epoxycyclohexyl and 3,4-epoxytricyclo[5.2.1.0 2,6 decane-yl are preferred.

[0065] Examples of the monomer that provides the structural unit (II) include vinyl compounds having an alicyclic epoxy group and (meth)acrylates having an alicyclic epoxy group. Among these, (meth)acrylates having an alicyclic epoxy group are preferred.

[0066] As the structural unit (II), a structural unit represented by any one of the following formulas (II-1) to (II-3) is preferred.

[0067] [Chemical formula 2]

[0068]

[0069] R 1 Each independently represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group, preferably a hydrogen atom or a methyl group.

[0070] L1 Each is independently a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms.

[0071] Examples of the divalent hydrocarbon group having 1 to 20 carbon atoms include: a divalent linear hydrocarbon group having 1 to 20 carbon atoms, a divalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and the like.

[0072] Examples of the divalent linear hydrocarbon group having 1 to 20 carbon atoms include: alkanediyls such as methanediyl, ethanediyl, propanediyl, butanediyl; alkenediyls such as ethenediyl, propenediyl, butenediyl; alkynediyls such as ethynediyl, propynediyl, butynediyl, and the like.

[0073] Examples of the divalent alicyclic hydrocarbon group having 3 to 20 carbon atoms include: divalent monocyclic alicyclic saturated hydrocarbon groups such as cyclopentanediyl, cyclohexanediyl; divalent monocyclic alicyclic unsaturated hydrocarbon groups such as cyclopentenediyl, cyclohexenediyl; divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornanediyl, adamantanediyl, tricyclodecanediyl; divalent polycyclic alicyclic unsaturated hydrocarbon groups such as norbornenediyl, tricyclodecenediyl, and the like.

[0074] Examples of the divalent aromatic hydrocarbon group having 6 to 20 carbon atoms include: arenediyls such as benzenediyl, toluenediyl, xylenediyl, naphthalenediyl, anthracenediyl; arenediylalkanediyls such as benzenediyimethanediyl, benzenediylethanediyl, naphthalenediyimethanediyl, anthracenediyimethanediyl, and the like.

[0075] n is an integer of 1 to 5, preferably an integer of 1 to 3, more preferably 1 or 2.

[0076] k1 is 0 or 1.

[0077] X 1 is a hydroxyl group, a halogen atom, a cyano group, a nitro group, an alkyl group, or an alkoxy group.

[0078] As the alkyl group, the alkyl group having 1 to 10 carbon atoms represented by R 11 ~R 13 in the following formula (1) can be preferably used. As the alkoxy group, the alkoxy group having 1 to 6 carbon atoms represented by R 11 ~R 13 in the following formula (1) can be preferably used.

[0079] a1 is an integer of 0 to 3. When a1 is 2 or more, the plurality of X 1 are the same as or different from each other.

[0080] Specific examples of the structural unit (II) include the structural units shown below, but are not limited thereto.

[0081] [Chemical formula 3]

[0082]

[0083] (In the formula, R 1 has the same meaning as in the above formulas (II-1) to (II-3))

[0084] With respect to all the structural units constituting the polymer component (A), the content ratio of the structural unit (II) (the total content ratio in the case of containing a plurality of them) is 10% by mass or more, more preferably 12% by mass or more, still more preferably 15% by mass or more. The content ratio is preferably 70% by mass or less, more preferably 60% by mass or less, still more preferably 50% by mass or less. By setting the content ratio of the structural unit (II) within the above range, a cured film having excellent melt flowability and chemical resistance can be formed.

[0085] (Structural unit (III))

[0086] By the polymer component (A) containing a polymer having the structural unit (III), a cured film having excellent relative dielectric constant and chemical resistance can be formed.

[0087] The structural unit (III) is a structural unit derived from a (meth)acrylate having an alicyclic structure, excluding those equivalent to the structural unit (II).

[0088] Examples of the alicyclic structure include alicyclic structures having 3 to 20 ring members.

[0089] The alicyclic structure having 3 to 20 ring members is not particularly limited as long as it has an alicyclic structure, and may have a monocyclic, bicyclic, tricyclic, tetracyclic or higher polycyclic structure, and may also be a bridged ring structure, a spiro ring structure, a ring assembly structure in which a plurality of rings are directly bonded by a single bond or a double bond, or any combination thereof. Among these, a bridged ring structure having a monocyclic, bicyclic or tricyclic structure is preferred, and cyclopentane, cyclohexane, norbornane, adamantane, tricyclo[5.2.1.0 2,6 decane are preferred. Among these, from the viewpoint of radiation sensitivity, monocyclic structures such as cyclopentane and cyclohexane are more preferred.

[0090] As the structural unit (III), a structural unit represented by any one of the following formulas (III-1) to (III-4) is preferred.

[0091] [Chemical formula 4]

[0092]

[0093] R 2 are each independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group, preferably a hydrogen atom or a methyl group.

[0094] L 2 is independently a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms. As the divalent hydrocarbon group having 1 to 20 carbon atoms, those same as the divalent hydrocarbon group having 1 to 20 carbon atoms represented by L in the formulas (II-1) to (II-3) can be preferably used. 1

[0095] p is an integer of 1 to 5, preferably an integer of 1 to 3, more preferably 1 or 2.

[0096] k2 is 0 or 1.

[0097] X 2 is a hydroxyl group, a halogen atom, a cyano group, a nitro group, an alkyl group, or an alkoxy group. As the alkyl group and the alkoxy group, those exemplified for X in the formulas (II-1) to (II-3) can be preferably used. 1

[0098] a2 is an integer of 0 to 3. When a2 is 2 or more, the plurality of Xs 2 are the same as or different from each other.

[0099] As specific examples of the structural unit (III), the structural units shown below can be cited, but are not limited thereto.

[0100] [Chemical formula 5]

[0101]

[0102] (In the formula, R 2 has the same meaning as in the formulas (III-1) to (III-4))

[0103] The content ratio of the structural unit (III) (the total content ratio in the case of containing a plurality of them) with respect to all the structural units constituting the polymer component (A) is 10% by mass or more, more preferably 12% by mass or more, still more preferably 15% by mass or more. The content ratio is preferably 60% by mass or less, more preferably 50% by mass or less, still more preferably 40% by mass or less. By setting the content ratio of the structural unit (III) within the above range, a cured film having excellent relative dielectric constant and radiation sensitivity can be formed.

[0104] (Structural unit (IV))

[0105] The polymer component (A) may further contain a structural unit (IV) having an alkoxysilyl group. As the alkoxysilyl group, a group represented by the following formula (1) can be cited.

[0106] [Chemical formula 6]

[0107] ​​

[0108] (In formula (1), R 11 , R 12 and R 13 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or a phenyl group. Among them, one or more of R 11 , R 12 and R 13 are alkoxy groups having 1 to 6 carbon atoms. "*" represents a bonding site)

[0109] In the said formula (1), as the alkoxy group having 1 to 6 carbon atoms represented by R 11 to R 13 , examples include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, and tert-butoxy group, etc. Among these, the alkoxy groups represented by R 11 to R 13 preferably have 1 to 3 carbon atoms, and more preferably are methoxy group or ethoxy group.

[0110] R 11 to R 13 The alkyl group having 1 to 10 carbon atoms represented by may be linear or branched. As the alkyl group having 1 to 10 carbon atoms represented by R 11 to R 13 , examples include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, etc. Among these, the alkyl groups represented by R 11 to R 13 preferably are methyl group, ethyl group or propyl group.

[0111] One of the groups represented by R 11 to R 13 is an alkoxy group having 1 to 6 carbon atoms. The remaining groups are preferably a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms or a phenyl group, more preferably a hydroxyl group, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and still more preferably an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms.

[0112] R 11 to R 13 Preferably, two or more of these are alkoxy groups having 1 to 6 carbon atoms, and more preferably all are alkoxy groups having 1 to 6 carbon atoms.

[0113] The structural unit (IV) is preferably a structural unit derived from a monomer having a polymerizable carbon-carbon unsaturated bond (hereinafter, also referred to as "unsaturated monomer"). Specifically, it is preferably at least one selected from the group consisting of the structural unit represented by the following formula (1-1) and the structural unit represented by the following formula (1-2).

[0114] [Chemical formula 7]

[0115]

[0116] (In formulas (1-1) and (1-2),

[0117] R A is a hydrogen atom, a methyl group, a hydroxymethyl group, a cyano group, or a trifluoromethyl group.

[0118] R 7 and R 8 are each independently a divalent aromatic ring group or a chain hydrocarbon group.

[0119] R 11 、R 12 and R 13 have the same meaning as in formula (1))

[0120] In the formulas (1-1) and (1-2), the divalent aromatic ring group in R 7 、R 8 is preferably a substituted or unsubstituted phenylene group or a substituted or unsubstituted naphthylene group. The divalent chain hydrocarbon group is preferably an alkanediyl group having 1 to 6 carbon atoms, more preferably an alkanediyl group having 1 to 4 carbon atoms, and still more preferably a linear alkanediyl group having 1 to 4 carbon atoms.

[0121] As specific examples of the monomer that provides the structural unit (IV), the following can be cited: styryltrimethoxysilane, styryltriethoxysilane, styrylmethyldimethoxysilane, styrylethyldiethoxysilane, styryldimethoxyhydroxysilane, styryldiethoxyhydroxysilane, (meth)acryloxyphenyltrimethoxysilane, (meth)acryloxyphenyltriethoxysilane, (meth)acryloxyphenylmethyldimethoxysilane, (meth)acryloxyphenylethyldiethoxysilane, etc.; trimethoxy(4-vinylnaphthyl)silane, triethoxy(4-vinylnaphthyl)silane, methyldimethoxy(4-vinylnaphthyl)silane, ethyldiethoxy(4-vinylnaphthyl)silane, (meth)acryloxynaphthyltrimethoxysilane, etc.; 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 4-(meth)acryloxybutyltrimethoxysilane, etc. Among these, styryltrimethoxysilane, styryltriethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 4-(meth)acryloxybutyltrimethoxysilane are preferred, and 3-(meth)acryloxypropyltrimethoxysilane and 3-(meth)acryloxypropyltriethoxysilane are more preferred.

[0122] When the polymer component (A) contains the structural unit (IV), the content ratio of the structural unit (IV) (the total content ratio in the case of containing a plurality of them) is preferably 0.5% by mass or more, more preferably 1% by mass or more, and still more preferably 3% by mass or more, relative to all the structural units constituting the polymer component (A). The content ratio is preferably 20% by mass or less, more preferably 15% by mass or less, and still more preferably 10% by mass or less. By setting the content ratio of the structural unit (IV) within the above range, a cured film having more excellent radiation sensitivity and chemical resistance can be obtained, which is therefore preferred.

[0123] The polymer component (A) may further contain structural units other than the structural units (I) to (IV). Examples of other structural units include: a structural unit (V) derived from an aromatic vinyl compound, a structural unit (VI) derived from an N-substituted maleimide compound, a structural unit (VII) having a hydroxyl group, a structural unit (VIII) derived from an alkyl methacrylate compound, a structural unit (IX) having an epoxy group (excluding those equivalent to the structural unit (II)), and the like. By the polymer component (A) containing at least one of the structural unit (V) and the structural unit (VI), the glass transition temperature (Tg) of the polymer component (A) can be further increased, and the improvement effect of the pattern shape can be enhanced, which is preferred in this regard.

[0124] (Structural unit (V))

[0125] The aromatic vinyl compound constituting the structural unit (V) is not particularly limited. Examples include: styrene-based compounds such as styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 5-tert-butyl-2-methylstyrene, divinylbenzene, trivinylbenzene, tert-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl)dimethylaminoethyl ether, N,N-dimethylaminoethylstyrene, N,N-dimethylaminomethylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-tert-butylstyrene, 3-tert-butylstyrene, 4-tert-butylstyrene, diphenylethylene; vinylnaphthalene-based compounds such as vinylnaphthalene, divinylnaphthalene; and heterocyclic vinyl compounds such as vinylpyridine. Among these, the aromatic vinyl compound is preferably a styrene-based compound.

[0126] When the polymer component (A) contains the structural unit (V), the content ratio of the structural unit (V) (the total content ratio in the case of containing a plurality of them) is preferably 0.5% by mass or more, more preferably 1% by mass or more, relative to all the structural units constituting the polymer component (A). The content ratio is preferably 30% by mass or less, more preferably 25% by mass or less. By setting the content ratio of the structural unit (V) within the above range, a cured film with a better pattern shape can be obtained, the glass transition temperature of the polymer component (A) will not become too high, and the reduction in developability can be suppressed, which is therefore preferred.

[0127] (Structural unit (VI))

[0128] As the N-substituted maleimide compound that constitutes the structural unit (VI), compounds in which the hydrogen atom bonded to the nitrogen atom of maleimide is substituted with a monovalent hydrocarbon group can be mentioned. Examples of the monovalent hydrocarbon group include: a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, and a monovalent aromatic hydrocarbon group. Among these, in terms of the aspect of further improving the heat resistance improvement effect, the N-substituted maleimide compound that constitutes the structural unit (VI) preferably has a monovalent cyclic hydrocarbon group, and more preferably has a monovalent alicyclic hydrocarbon group containing a monocyclic, bridged ring or spiro ring.

[0129] Specifically, the structural unit (VI) is preferably a structural unit represented by the following formula (2).

[0130] [Chemical formula 8]

[0131]

[0132] (In formula (2),

[0133] R 5 is a monovalent cyclic hydrocarbon group.

[0134] R 6 and R 7 are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms)

[0135] In the formula (2), in R 5 , the ring structure of the cyclic hydrocarbon group may be directly bonded to the nitrogen atom, or the ring structure may be bonded via a divalent linking group. Examples of the divalent linking group include: alkanediyls such as methylene, ethylene, 1,3-propanediyl, etc. Among these, R 5 is preferably a cyclic hydrocarbon group in which the ring structure is directly bonded to the nitrogen atom, and more preferably an alicyclic hydrocarbon group in which the structure of the alicyclic hydrocarbon is directly bonded to the nitrogen atom. R 6 and R 7 are preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.

[0136] Specific examples of the N-substituted maleimide compound include, as the compound having an alicyclic hydrocarbon group, for example: N-cyclohexyl maleimide, N-cyclopentyl maleimide, N-(2-methylcyclohexyl) maleimide, N-(4-methylcyclohexyl) maleimide, N-(4-ethylcyclohexyl) maleimide, N-(2,6-dimethylcyclohexyl) maleimide, N-norbornanyl maleimide, N-tricyclodecanyl maleimide, N-adamantyl maleimide, etc.; as the compound having an aromatic hydrocarbon group, for example: N-phenyl maleimide, N-(2-methylphenyl) maleimide, N-(4-methylphenyl) maleimide, N-(4-ethylphenyl) maleimide, N-(2,6-dimethylphenyl) maleimide, N-benzyl maleimide, N-naphthyl maleimide, etc. Among these, the N-substituted maleimide compound is preferably at least one selected from the group consisting of N-cyclohexyl maleimide, N-(4-methylcyclohexyl) maleimide, N-phenyl maleimide, and N-(4-methylphenyl) maleimide, and more preferably N-cyclohexyl maleimide.

[0137] When the polymer component (A) contains the structural unit (VI), from the viewpoint of making the melt fluidity good, the content ratio of the structural unit (VI) (the total content ratio in the case of containing a plurality of them) is preferably 2% by mass or more, more preferably 5% by mass or more, and still more preferably 10% by mass or more, with respect to all the structural units constituting the polymer component (A). From the viewpoint of radiation sensitivity, the content ratio is preferably 40% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less.

[0138] (Structural unit (VII))

[0139] The structural unit (VII) is preferably a structural unit derived from an unsaturated monomer having a hydroxyl group (alcoholic hydroxyl group). Specifically, a structural unit derived from a monomer having one or more hydroxyl groups bonded to a saturated chain hydrocarbon group can be cited. By the polymer component (A) containing the structural unit (VII), a decrease in pattern forming ability caused by a deviation in pre-baking temperature during film formation can be suppressed, and a good pattern can be formed, which is preferable in terms of the above aspect and radiation sensitivity. The structural unit (VII) is not particularly limited. For example, (meth)acrylic compounds and maleimide compounds can be cited.

[0140] Specific examples of the structural unit (VII) include, as (meth)acrylic compounds, for example: hydroxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, glycerol mono(meth)acrylate, etc.; as maleimide compounds, for example: N-(hydroxymethyl)maleimide, N-(2-hydroxyethyl)maleimide, N-(3-hydroxypropyl)maleimide, etc.

[0141] When the polymer component (A) contains the structural unit (VII), from the viewpoint of suppressing the decrease in the pattern forming ability caused by the deviation of the pre-baking temperature, the content ratio (the total content ratio in the case of containing a plurality of them) of the structural unit (VII) is 1% by mass or more, more preferably 5% by mass or more, and further preferably 10% by mass or more, relative to all the structural units constituting the polymer component (A). From the viewpoint of suppressing the decrease in developability, the content ratio is preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 30% by mass or less.

[0142] (Structural unit (VIII))

[0143] For the purpose of adjusting the glass transition temperature of the polymer, etc., the structural unit (VIII) may be contained in the polymer component (A). The monomer constituting the structural unit (VIII) is preferably a methacrylate compound in which the alkyl group bonded to the ester group has 1 to 10 carbon atoms, and examples thereof include acrylic alkyl ester compounds such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, etc.

[0144] When the polymer component (A) contains the structural unit (VIII), the content ratio (the total content ratio in the case of containing a plurality of them) of the structural unit (VIII) is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more, relative to all the structural units constituting the polymer component (A). The content ratio is preferably 80% by mass or less, more preferably 70% by mass or less, and further preferably 60% by mass or less.

[0145] (Structural unit (IX))

[0146] The structural unit (IX) is a structural unit derived from an unsaturated monomer having an epoxy group, except for those equivalent to the structural unit (II). Specific examples of the structural unit (IX) include at least one selected from the group consisting of the structural unit represented by the following formula (5-1) and the structural unit represented by the following formula (5-2).

[0147] [Chemical formula 9]

[0148]

[0149] (In formula (5-1) and formula (5-2),

[0150] R 20 is a group having an oxiranyl group or an oxetanyl group (wherein, an alicyclic epoxy group is excluded).

[0151] R A1 is a hydrogen atom, a methyl group, a hydroxymethyl group, a cyano group, or a trifluoromethyl group.

[0152] L 3 is a single bond or a divalent linking group)

[0153] In the formulas (5-1) and (5-2), as R 20 , examples include: an oxiranyl group, an oxetanyl group, a 3-ethyloxetanyl group, etc.

[0154] As the divalent linking group in L 3 , examples include: an alkanediyl group such as a methylene group, an ethylene group, a 1,3-propanediyl group; a divalent group in which any methylene group in the alkanediyl group is substituted with -O-, etc.

[0155] Specific examples of the monomer having an epoxy group include: glycidyl (meth)acrylate, (3-methyloxetan-3-yl)methyl (meth)acrylate, (3-ethyloxetan-3-yl) (meth)acrylate, (oxetan-3-yl)methyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, etc.

[0156] When the polymer component (A) contains the structural unit (IX), the content ratio of the structural unit (IX) (the total content ratio in the case of containing a plurality of them) is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 15% by mass or more, relative to all the structural units constituting the polymer component (A). The content ratio is preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 35% by mass or less.

[0157] (Other structural units)

[0158] As other structural units, in addition to those listed above, for example, structural units derived from the following monomers can be listed: unsaturated dicarboxylic acid dialkyl ester compounds such as diethyl itaconate; unsaturated dicarboxylic anhydrides such as phthalic anhydride; conjugated diene compounds such as 1,3-butadiene and isoprene; nitrogen-containing vinyl compounds such as (meth)acrylonitrile, (meth)acrylamide, N-vinylalkylamide, and N-vinylpyrrolidone; monomers such as vinyl chloride, vinylidene chloride, and vinyl acetate. In the polymer component (A), the content ratio of other structural units is preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably 1% by mass or less, relative to all the structural units constituting the polymer component (A).

[0159] The content ratio of each structural unit is usually equivalent to the ratio of the monomers used in the production of the polymer component (A).

[0160] In the polymer component (A), the weight average molecular weight (Mw) in terms of polystyrene obtained by gel permeation chromatography (GPC) is preferably 2,000 or more. If Mw is 2,000 or more, a cured film with sufficiently high chemical resistance and good developability can be obtained, which is preferable in this regard. Mw is more preferably 5,000 or more, still more preferably 6,000 or more, and particularly preferably 8,000 or more. In addition, from the viewpoint of good film-forming properties, Mw is preferably 50,000 or less, more preferably 30,000 or less, still more preferably 20,000 or less, still more preferably 18,000 or less, and particularly preferably 15,000 or less.

[0161] In the polymer component (A), the molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 4.0 or less, more preferably 3.0 or less, and still more preferably 2.7 or less. In addition, when the polymer component (A) contains two or more polymers, it is preferable that each polymer satisfies the above ranges of Mw and Mw / Mn.

[0162] The content ratio of the polymer component (A) is preferably 10% by mass or more, more preferably 30% by mass or more, and still more preferably 50% by mass or more, relative to the total amount of the solid components contained in the radiation-sensitive composition. In addition, the content ratio of the polymer component (A) is preferably 95% by mass or less, more preferably 90% by mass or less, relative to the total amount of the solid components contained in the radiation-sensitive composition. By setting the content ratio of the polymer component (A) within the above range, a cured film with sufficiently high chemical resistance and good developability and transparency can be obtained, which is preferable in this regard.

[0163] As the polymer component (A), for example, an unsaturated monomer capable of introducing the respective structural units can be used, and it can be produced in an appropriate solvent in the presence of a polymerization initiator or the like according to existing methods such as radical polymerization. Specifically, examples of the polymerization initiator used include azo compounds such as 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), and dimethyl 2,2'-azobis(isobutyrate). The usage ratio of the polymerization initiator is preferably 0.01 part by mass to 30 parts by mass relative to 100 parts by mass of the total amount of the monomers used in the reaction. Examples of the polymerization solvent include alcohols, ethers, ketones, esters, hydrocarbons, and the like.

[0164] In the polymerization reaction, the reaction temperature is generally 30°C to 180°C. The reaction time varies depending on the type of the initiator and the monomer or the reaction temperature, but is generally 0.5 hour to 10 hours. The usage amount of the organic solvent is preferably set such that the total amount of the monomers used in the reaction is 0.1% by mass to 60% by mass relative to the total amount of the reaction solution. The polymer obtained by the polymerization reaction can be separated by existing separation methods such as the following methods: a method of injecting the reaction solution into a large amount of poor solvent and drying the precipitate thus obtained under reduced pressure; a method of subjecting the reaction solution to vacuum distillation using an evaporator to remove it, and the like.

[0165] <Quinonediazide compound (B)>

[0166] The quinonediazide compound (B) is a radiation-sensitive acid generator that generates carboxylic acid upon irradiation with radiation. As the quinonediazide compound, a condensate of a phenolic compound or an alcoholic compound (hereinafter also referred to as "parent nucleus") and 1,2-naphthoquinonediazide sulfonyl halide is preferably used.

[0167] As the mother nucleus, for example, the following can be cited: trihydroxybenzophenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, hexahydroxybenzophenone, (polyhydroxyphenyl)alkane, and other mother nuclei. Specific examples of these are as follows. As trihydroxybenzophenone, for example, 2,3,4-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, etc. can be cited; as tetrahydroxybenzophenone, for example, 2,2',4,4'-tetrahydroxybenzophenone, 2,3,4,3'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,3,4,2'-tetrahydroxy-4'-methylbenzophenone, 2,3,4,4'-tetrahydroxy-3'-methoxybenzophenone, etc. can be cited; as pentahydroxybenzophenone, for example, 2,3,4,2',6'-pentahydroxybenzophenone, etc. can be cited; as hexahydroxybenzophenone, for example, 2,4,6,3',4',5'-hexahydroxybenzophenone, 3,4,5,3',4',5'-hexahydroxybenzophenone, etc. can be cited; as (polyhydroxyphenyl)alkane, for example, bis(2,4-dihydroxyphenyl)methane, bis(p-hydroxyphenyl)methane, 1,1,1-tris(p-hydroxyphenyl)methane, 1,1,1-tris(p-hydroxyphenyl)ethane, bis(2,3,4-trihydroxyphenyl)methane, 2,2-bis(2,3,4-trihydroxyphenyl)propane, 1,1,3-tris(2,5-dimethyl-4-hydroxyphenyl)-3-phenylpropane, 4,4'-[1-[4-[1-[4-hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol, bis(2,5-dimethyl-4-hydroxyphenyl)-2-hydroxyphenylmethane, 3,3,3',3'-tetramethyl-1,1'-spirobiindene-5,6,7,5',6',7'-hexol, 2,2,4-trimethyl-7,2',4'-trihydroxyflavane, etc. can be cited; as other mother nuclei, for example, 2-methyl-2-(2,4-dihydroxyphenyl)-4-(4-hydroxyphenyl)-7-hydroxychromane, 2-[bis{(5-isopropyl-4-hydroxy-2-methyl)phenyl}methyl], etc. can be cited.

[0168] As the mother nucleus, preferably, 2,3,4,4'-tetrahydroxybenzophenone, 1,1,1-tris(p-hydroxyphenyl)methane, 1,1,1-tris(p-hydroxyphenyl)ethane, and 4,4'-[1-[4-[1-[4-hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol among these are used.

[0169] As 1,2-naphthoquinone diazosulfonyl halide, 1,2-naphthoquinone diazosulfonyl chloride is preferred. Specifically, 1,2-naphthoquinone diazo-4-sulfonyl chloride, 1,2-naphthoquinone diazo-5-sulfonyl chloride, etc. can be cited. Among these, as 1,2-naphthoquinone diazosulfonyl halide, 1,2-naphthoquinone diazo-5-sulfonyl chloride can be preferably used.

[0170] In the condensation reaction for obtaining the condensate, regarding the ratio of the parent nucleus to 1,2-naphthoquinone diazide sulfonyl halide, the amount of 1,2-naphthoquinone diazide sulfonyl halide used is set to an amount corresponding to 30 mol% to 85 mol%, more preferably 50 mol% to 70 mol%, relative to the number of OH groups in the parent nucleus. In addition, the condensation reaction can be carried out according to existing methods. A 1,2-quinone diazide compound can be obtained through the condensation reaction of the parent nucleus and 1,2-naphthoquinone diazide sulfonyl halide.

[0171] With respect to 100 parts by mass of the polymer component (A), the content ratio of the quinone diazide compound (B) in the radiation-sensitive composition is preferably set to 2 parts by mass or more, more preferably set to 5 parts by mass or more, and further preferably set to 10 parts by mass or more. In addition, with respect to 100 parts by mass of the polymer component (A), the content ratio of the quinone diazide compound (B) is preferably set to 60 parts by mass or less, more preferably set to 40 parts by mass or less, and further preferably set to 30 parts by mass or less. If the content ratio of the quinone diazide compound (B) is set to 2 parts by mass or more, acid is sufficiently generated by irradiation with radiation, and the difference in solubility between the irradiated portion and the non-irradiated portion with respect to the alkaline solution can be sufficiently increased, so it is preferred. Thus, good patterning can be performed. In addition, the amount of acid participating in the reaction with the polymer component (A) can be increased, and chemical resistance can be sufficiently ensured, so it is preferred. On the other hand, if the content ratio of the quinone diazide compound (B) is set to 60 parts by mass or less, the unreacted quinone diazide compound (B) can be sufficiently reduced, and a decrease in developability caused by the remaining quinone diazide compound (B) can be suppressed, which is preferred in this regard.

[0172] <Solvent (C)>

[0173] The radiation-sensitive composition of the present disclosure is a liquid composition in which the polymer component (A), the quinone diazide compound (B), and other components optionally formulated are preferably dissolved or dispersed in the solvent (C). As the solvent used, an organic solvent that preferably dissolves the components formulated in the radiation-sensitive composition and does not react with the components is preferred.

[0174] The solvent (C) is not particularly limited, and examples thereof include alcohol solvents, ether solvents, ester solvents, ketone solvents, amide solvents, etc. The solvent (C) can be used alone or in combination of two or more.

[0175] As the alcohol solvent, for example, alkyl alcohols such as methanol, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-hexanol, 1-octanol, 1-nonanol, 1-dodecanol, 1-methoxy-2-propanol, and diacetone alcohol; and aromatic alcohols such as benzyl alcohol can be cited.

[0176] As ether solvents, for example, the following can be cited: ethylene glycol monoalkyl ethers such as diethylene glycol methyl ethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether; diethylene glycol monoalkyl ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether; diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether; dipropylene glycol monoalkyl ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, etc.

[0177] As ester solvents, for example, the following can be cited: carboxylic acid esters such as ethyl acetate, isopropyl acetate, n-butyl acetate, amyl acetate, ethyl lactate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate; polyol carboxylic acid ester solvents such as propylene glycol diacetate; polyol partial ether carboxylic acid ester solvents such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc.

[0178] As ketone solvents, for example, the following can be cited: acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, methyl amyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, etc.

[0179] Among these, ether solvents and ester solvents are preferred, ester solvents are more preferred, and polyol partial ether carboxylic acid ester solvents are even more preferred. In addition, among ether solvents and ester solvents, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, and methyl 3-methoxypropionate are preferred.

[0180] The content of the solvent (C) in the present composition is not particularly limited, but it is preferably adjusted so that the concentration of the solid components (components other than the solvent (C)) of the present composition is within the following range. As the lower limit value of the solid component concentration in the present composition, 5% by mass is preferred, 8% by mass is more preferred, and 15% by mass is even more preferred. On the other hand, as the upper limit value of the solid component concentration, 60% by mass is preferred, 40% by mass is more preferred, and 30% by mass is even more preferred. If the solid component concentration of the radiation-sensitive composition is 5% by mass or more, the film thickness of the coating film can be sufficiently ensured when the radiation-sensitive composition is coated on a substrate, and it is preferred in this regard. In addition, if the solid component concentration is 60% by mass or less, the film thickness of the coating film will not be too large, and furthermore, the viscosity of the radiation-sensitive composition can be moderately increased, and good coatability can be ensured, and it is preferred in this regard.

[0181] <Solvent (C1)>

[0182] In addition to the solvent (C), the composition of the present disclosure may contain a solvent (C1) having a boiling point of 180 °C or higher and a hydrogen bond term δH of the Hansen solubility parameter of 3.0 or higher and 13.0 or lower. Here, the Hansen solubility parameter (HSP (Hansen Solubility Parameter) value) is an index that divides the solubility parameter (SP (Solubility Parameter) value) of Hildebrand into three components: a dispersion force term δD, a polar term δP, and a hydrogen bond term δH, taking into account the polarity of physical properties, and has the relationship of "SP 2 = δD 2 + δP 2 + δH 2 ". In the present specification, the Hansen solubility parameter is a value calculated using the calculation software HSPiP ver.5. The boiling point of the solvent is the value at 1 atmosphere.

[0183] The solvent (C1) only needs to have a boiling point of 180 °C or higher and a hydrogen bond term δH of the HSP value of 3.0 or higher and 13.0 or lower, and its type is not particularly limited. Among them, the solvent (C1) is preferably at least one selected from the group consisting of alcohols, carbonates, ethers, and esters. The solvent (C1) may be a compound containing a chain structure or a compound having a cyclic structure.

[0184] Specific examples of the solvent (C1) include: dihydroterpineol (δH = 6.69, boiling point = 210 °C), (S)-4-methyl-1,3-dioxolan-2-one (δH = 7.35, boiling point = 242 °C), diethylene glycol monobutyl ether (δH = 10.46, boiling point = 231 °C), dipropylene glycol methyl ether acetate (δH = 5.78, boiling point = 213 °C), triethylene glycol monobutyl ether (δH = 9.14, boiling point = 278 °C), propyl lactate (δH = 11.7, boiling point = 188 °C), benzyl alcohol (δH = 12.5, boiling point = 205 °C), etc.

[0185] When the solvent (C) contains the solvent (C1), the content of the solvent (C1) is preferably 10% by mass or less based on the total amount of the solvent.

[0186] <Other components>

[0187] In addition to the polymer component (A), quinonediazide compound (B), and solvent (C), the radiation-sensitive composition of the present disclosure may also contain components other than these (hereinafter also referred to as "other components"). Examples of other components include: reaction initiators (photo radical polymerization initiators, photo cationic polymerization initiators, etc.), polyfunctional polymerizable compounds (polyfunctional (meth)acrylates, etc.), adhesion promoters (functional silane coupling agents, etc.), surfactants (fluorine-based surfactants, silicone-based surfactants (silane-based surfactants), nonionic surfactants, etc.), polymerization inhibitors, antioxidants, chain transfer agents, etc. The blending ratios of these components can be appropriately selected according to each component within the range that does not impair the effects of the present disclosure. In addition, the radiation-sensitive composition of the present disclosure may contain a silane-based surfactant, but preferably does not contain it.

[0188] The solid content concentration of the radiation-sensitive composition of the present disclosure (the ratio of the total mass of the components other than the solvent (C) in the radiation-sensitive composition to the total mass of the radiation-sensitive composition) can be appropriately selected in consideration of viscosity, volatility, etc.

[0189] (Dielectric constant of the cured film obtained from the radiation-sensitive composition)

[0190] By curing this composition, a cured film with a sufficiently low dielectric constant can be obtained. Specifically, the dielectric constant of the obtained cured film at a frequency of 10 kHz is preferably 3.4 or less, more preferably less than 3.1. In addition, for the details of the method for measuring the dielectric constant of the cured film, refer to the method described in the examples below.

[0191] The radiation-sensitive composition of the present disclosure, by using a quinonediazide compound (B) as a radiation-sensitive acid generator together with a polymer component (A) containing structural units (I) to (III), can maintain a high radiation sensitivity while increasing the glass transition temperature of the polymer. As a result, a cured film can be formed that suppresses melt flow, has a good pattern shape, can sufficiently reduce the relative dielectric constant, and has excellent chemical resistance. Such a radiation-sensitive composition of the present disclosure is effectively used as a composition for forming a planarization film or an interlayer insulating film of a display element.

[0192] 《Method for manufacturing a cured film》

[0193] The cured film of the present disclosure is formed from the radiation-sensitive composition prepared as described above. The radiation-sensitive composition of the present disclosure has a high radiation sensitivity, and in addition, can suppress melt flow caused by heat after patterning, and also has good relative dielectric constant and chemical resistance.

[0194] When manufacturing a hardened film, the radiation-sensitive composition is used, whereby a positive-type hardened film can be formed by irradiation with radiation (such as ultraviolet rays, far ultraviolet rays, visible light, etc.). The hardened film of the present disclosure can be manufactured by a method including, for example, the following (Process 1) to (Process 5).

[0195] (Process 1) A process of coating a radiation-sensitive composition on a substrate to form a coating film.

[0196] (Process 2) A process of removing a solvent from the coating film.

[0197] (Process 3) A process of irradiating the coating film after removing the solvent with radiation.

[0198] (Process 4) A process of developing the coating film irradiated with radiation.

[0199] (Process 5) A process of thermally hardening the developed coating film.

[0200] Hereinafter, each process will be described in detail.

[0201] <Process 1 and Process 2: Coating Film Formation Process>

[0202] In this process, the radiation-sensitive composition is coated on the surface where the coating film is to be formed (hereinafter also referred to as the "film-forming surface"), and preferably, the solvent is removed by heat treatment (pre-baking) to form a coating film on the film-forming surface. The material of the film-forming surface is not particularly limited. For example, when using a radiation-sensitive composition to form a planarization film, the radiation-sensitive composition is coated on a substrate provided with switching elements such as thin film transistors (TFTs) to form a coating film. As the substrate, for example, a glass substrate or a resin substrate can be used.

[0203] As a coating method of the radiation-sensitive composition, for example, spray coating, roll coating, spin coating, slit die coating, bar coating, and inkjet printing can be mentioned. Among these, spin coating, slit die coating, or bar coating is preferably used. As the pre-baking conditions, they also vary depending on the types and content ratios of the respective components of the radiation-sensitive composition. For example, it is carried out at 60°C to 130°C for 0.5 minutes to 10 minutes. The film thickness of the formed coating film (i.e., the film thickness after pre-baking) is preferably 1 μm to 12 μm.

[0204] <Process 3: Exposure Process>

[0205] In this step, at least a part of the coating film formed in the above-mentioned Step 1 and Step 2 is irradiated with radiation. At this time, by interposing a mask having a specified pattern and irradiating the coating film with radiation, a hardened film (for example, an interlayer insulating film) having a pattern can be formed. Examples of the radiation include ultraviolet rays, far ultraviolet rays, visible light, X-rays, charged particle beams such as electron beams, etc. Among these, ultraviolet rays are preferably used, and examples thereof include g rays (wavelength 436 nm) and i rays (wavelength 365 nm). The exposure amount of the radiation is preferably 0.1 J / m 2 ~20,000 J / m 2 .

[0206] <Step 4: Development Step>

[0207] In this step, the coating film irradiated with radiation in the above-mentioned Step 3 is developed. Specifically, positive development is performed in which the coating film irradiated with radiation in Step 3 is developed using a developer to remove the irradiated portion of the radiation. Examples of the developer include an aqueous solution of an alkali (alkaline compound). Examples of the alkali include sodium hydroxide, tetramethylammonium hydroxide, and the alkalis exemplified in paragraph

[0127] of Japanese Patent Laid-Open No. 2016-145913. From the viewpoint of obtaining appropriate developability, the alkali concentration of the aqueous alkali solution is preferably 0.1 mass% to 5.0 mass%. Examples of the development method include appropriate methods such as the liquid covering method, the dipping method, the shaking dipping method, and the spraying method. The development time also varies depending on the composition of the composition, and is, for example, 30 seconds to 120 seconds. In addition, it is preferable to perform a rinsing treatment of washing the patterned coating film with running water after the development step.

[0208] <Step 5: Heating Step>

[0209] In this step, a treatment of heating the coating film developed in the above-mentioned Step 4 (post-baking) is performed. Thereby, a hardening reaction of the film is carried out, and a hardened film showing good chemical resistance is obtained. The post-baking can be performed using a heating device such as an oven or a hot plate, for example. Regarding the post-baking conditions, the heating temperature is, for example, 120°C to 250°C. In addition, for example, when performing the heating treatment on a hot plate, the heating time is 5 minutes to 40 minutes, and when performing the heating treatment in an oven, the heating time is 10 minutes to 80 minutes. As described above, a hardened film having a target pattern can be formed on the substrate.

[0210] In addition, a post-exposure process may also be included between Process 4 and Process 5. By irradiating the developed coating film with radiation, a hardened film excellent in melt fluidity resistance or transparency in the heating process can be formed. Examples of the radiation include: ultraviolet rays, far ultraviolet rays, visible light, X-rays, charged particle beams such as electron beams, etc. Among these, ultraviolet rays are preferred, and for example, g-rays (wavelength 436 nm), i-rays (wavelength 365 nm) can be cited. The exposure amount of the radiation is preferably 0.1 J / m 2 ~20,000 J / m 2 .

[0211] 《Hardened Film》

[0212] The hardened film of the present disclosure is formed using the radiation-sensitive composition. The radiation-sensitive composition of the present disclosure has high radiation sensitivity, and in addition, it can suppress the melt flow caused by heat after patterning, and also has good relative dielectric constant and chemical resistance. Therefore, the hardened film is effectively used as an insulating film of an organic electroluminescence (EL) element. Specifically, in the organic EL element, the hardened film can be used as a planarization film for planarizing surface unevenness caused by a thin film transistor (TFT) or the like, an interlayer insulating film for insulating wirings, a partition wall and a dam for defining a region where a light-emitting layer is formed, a protective film for protecting a TFT or the like, a spacer, an adhesive layer for a color filter, etc. In addition, in this specification, a "partition wall" is a member for color differentiation of a color filter or a color conversion layer using quantum dots, etc., and a "dam" refers to a member for differentiating a light-emitting layer. Among these, the hardened film of the present disclosure is particularly effectively used as an interlayer insulating film or a planarization film.

[0213] 《Display Element》

[0214] The display element of the present disclosure includes a hardened film formed using the radiation-sensitive composition. Examples of the display element include: a liquid crystal display element, an organic electroluminescence (EL) display element, a micro LED display element, etc.

[0215] The display element of the present disclosure can be effectively applied to various uses, for example, it can be used as: various display devices such as a clock, a portable game machine, a word processor, a note type personal computer, a car navigation system, a camcorder, a personal digital assistant (PDA), a digital camera, a mobile phone, a smart phone, various monitors, a liquid crystal television, an information display, etc.

[0216] [Examples]

[0217] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. In addition, "parts" and "%" in the examples and comparative examples are based on mass unless otherwise specified.

[0218] [Weight-average molecular weight (Mw) and number-average molecular weight (Mn)]

[0219] The Mw and Mn of the polymer are measured by the following method.

[0220] · Measurement method: Gel permeation chromatography (GPC) method

[0221] · Apparatus: GPC-101 manufactured by Showa Denko K.K.

[0222] · GPC column: Combining GPC-KF-801, GPC-KF-802, GPC-KF-803 and GPC-KF-804 manufactured by Shimadzu GLC K.K.

[0223] · Mobile phase: Tetrahydrofuran

[0224] · Column temperature: 40 °C

[0225] · Flow rate: 1.0 mL / min

[0226] · Sample concentration: 1.0 mass%

[0227] · Sample injection volume: 100 μL

[0228] · Detector: Differential refractometer

[0229] · Standard substance: Monodisperse polystyrene

[0230] [Monomer]

[0231] The monomers used in the synthesis of the copolymer are as follows.

[0232] (Structural unit (I))

[0233] MA: Methacrylic acid

[0234] PIPE: p-Isopropenylphenol

[0235] MI: Maleimide

[0236] (Structural unit (II))

[0237] ECHMA: 3,4-Epoxycyclohexylmethyl methacrylate

[0238] ETCDA: 3,4-Epoxytricyclo[5.2.1.0 2,6Decan-9-yl ester and 3,4-epoxytricyclo[5.2.1.0 2,6 Mixture with decan-8-yl ester [50:50 (molar ratio)]

[0239] (Structural unit (III))

[0240] CHMA: Cyclohexyl methacrylate

[0241] CHA: Cyclohexyl acrylate

[0242] DCM: Dicyclopentanyl methacrylate

[0243] DCA: Dicyclopentanyl acrylate

[0244] IBA: Isobornyl acrylate

[0245] (Structural unit (IV))

[0246] MPTMS: 3-Methacryloxypropyltrimethoxysilane

[0247] MPTES: 3-Methacryloxypropyltriethoxysilane

[0248] (Structural units other than structural units (I) to (IV))

[0249] CHMI: N-Cyclohexylmaleimide

[0250] GMA: Glycidyl methacrylate

[0251] MMA: Methyl methacrylate

[0252] HEMA: 2-Hydroxyethyl methacrylate

[0253] Hereinafter, unless otherwise specified, parts represent parts by weight.

[0254] <Synthesis of polymer (A)>

[0255] [Synthesis Example 1] Synthesis of polymer (A-1)

[0256] Into a flask including a cooling tube and a stirrer, 13 parts of dimethyl 2,2'-azobis(isobutyrate) and 200 parts of diethylene glycol methyl ether were charged. Subsequently, 13 parts of methacrylic acid, 15 parts of 3,4-epoxycyclohexylmethyl methacrylate, 15 parts of cyclohexyl methacrylate, and 57 parts of methyl methacrylate were charged. After nitrogen replacement, while gently stirring, the temperature of the solution was raised to 80 °C and maintained at this temperature for 5 hours, thereby obtaining a polymer solution containing polymer (A-1). The solid content concentration of the polymer solution was 35.3 mass%, the Mw of polymer (A-1) was 11,000, and the molecular weight distribution (Mw / Mn) was 2.4.

[0257] [Synthesis Examples 2 to 16, Comparative Synthesis Examples 1 to 6]

[0258] Synthesis of polymers (A-2) to (A-16), polymers (A'-1 to A'-6)

[0259] Using the components of the types and blending amounts (parts by mass) shown in Table 1, polymer solutions containing polymers (A-2) to (A-16), polymers (A'-1) to (A'-3), polymers (A'-5) to (A'-6) having the same solid content concentration, molecular weight, and molecular weight distribution as polymer (A-1) were obtained in the same manner as in Synthesis Example 1 except for this. Polymer (A'-4) was synthesized according to Synthesis Example 1 in paragraph

[0133] of Japanese Patent Laid-Open No. 2007-156471. In addition, in Tables 1 and 2 below, "-" indicates that the corresponding component is not used.

[0260] [Table 1]

[0261]

[0262] <Preparation of Radiation-Sensitive Composition>

[0263] The polymers (A), 1,2-quinone diazide compounds (B), and solvents (C) used in the preparation of the radiation-sensitive composition are shown below.

[0264] 《Polymer (A)》

[0265] A-1 to A-16: Polymers (A-1) to (A-16) synthesized in Synthesis Examples 1 to 16

[0266] A'-1 to A'-6: Polymers (A'-1) to (A'-6) synthesized in Comparative Synthesis Examples 1 to 6

[0267] 《Quinone Diazide (B)》

[0268] B-1: Condensate of 4,4'-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bisphenol (1.0 mol) and 1,2-naphthoquinone diazide-5-sulfonyl chloride (2.0 mol)

[0269] 《Solvent (C)》

[0270] C-1: Diethylene glycol methyl ether (EDM)

[0271] C-2: Propylene glycol monomethyl ether (PGME)

[0272] C-3: Propylene glycol monomethyl ether acetate (PGMEA)

[0273] <Preparation of Radiation-Sensitive Composition>

[0274] [Example 1]

[0275] To the polymer solution containing polymer (A-1), 20 parts of quinone diazide compound (B-1) was mixed relative to the amount equivalent to 100 parts (solid content) of polymer (A-1). Diethylene glycol methyl ether (EDM), propylene glycol monomethyl ether (PGME), and propylene glycol monomethyl ether acetate (PGMEA) were added so that the final solid content concentration was 20% by mass. They were added so that the ratio of the solvents in the radiation-sensitive composition became EDM:PGME:PGMEA = 50:25:25. Subsequently, filtration was performed using a membrane filter with a pore size of 0.2 μm to prepare a radiation-sensitive composition.

[0276] [Examples 2 to 16, Comparative Examples 1 to 6]

[0277] Using the components of the types and blending amounts (parts by mass) shown in Table 2, radiation-sensitive compositions of Examples 2 to 16 and Comparative Examples 1 to 6 were prepared in the same manner as in Example 1, except for this.

[0278] [Table 2]

[0279]

[0280] <Evaluation>

[0281] Hard films were formed from the radiation-sensitive compositions of Examples 1 to 16 and Comparative Examples 1 to 6, and the following items were evaluated by the methods described below. The evaluation results are shown in Table 3 below.

[0282] <Radiation Sensitivity>

[0283] Using a spinner, hexamethyldisilazane (HMDS) was coated on a 6-inch glass wafer, and heated at 60 °C for 1 minute (HMDS treatment). Using a spinner, each radiation-sensitive composition prepared as described above was coated on the wafer after the HMDS treatment. Then, after drying at 30 Pa for 1 second in a small-scale reduced-pressure drying apparatus, pre-baking was performed at 100 °C for 2 minutes to form a coating film with a film thickness of 3.0 μm. Subsequently, using an exposure machine (using "MPA-600FA" of Canon Inc.: ultra-high pressure mercury lamp), the exposure amount was changed, and the coating film was exposed through a mask having an exposure portion with a rectangle of 10 μm × 10 μm. Then, development was performed using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide at 25 °C by the liquid covering method. The development time was set to 80 seconds. Subsequently, rinsing was performed with ultrapure water for 1 minute, and then drying was performed, thereby forming a pattern on the wafer after the HMDS treatment. The entire surface of the coating film was exposed at 300 mJ / cm 2 and the wafer was post-baked by heating in a clean oven at 230 °C for 30 minutes to obtain a hardened film. The exposure amount required to form a pattern of 10 μm × 10 μm during development was investigated. It can be evaluated that the smaller the exposure amount, the better the radiation sensitivity.

[0284] (Evaluation criteria)

[0285] AA: Less than 90 mJ / cm 2

[0286] A: 90 mJ / cm 2 or more and less than 120 mJ / cm 2

[0287] B: 120 mJ / cm 2 or more and less than 150 mJ / cm 2

[0288] C: 150 mJ / cm 2 or more

[0289] <Melt resistance fluidity>

[0290] The cross-sectional shape of the coating film pattern resolved at the optimal exposure amount was observed using a scanning electron microscope. At the end point where the coating film pattern is in contact with the substrate, a tangent line was drawn to the coating film pattern, and the angle formed by the tangent line and the substrate surface was calculated. It can be evaluated that the higher the angle, the better the melt resistance fluidity is maintained after heating at 230 °C.

[0291] (Evaluation criteria)

[0292] AA: 70° or more

[0293] A: More than 60° and less than 70°

[0294] B: More than 40° and less than 60°

[0295] C: Less than 40°

[0296] <Relative dielectric constant>

[0297] Using a spinner, a radiation-sensitive composition was coated on a glass substrate with indium tin oxide (ITO), and then pre-baked on a hot plate at 100 °C for 2 minutes to form a coating film. The rotation speed of the spinner was adjusted so that the coating film thickness became an average film thickness of 3.0 μm after heating at 230 °C for 30 minutes described below. Thereafter, development was carried out by the liquid covering method at 25 °C using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide. The development time was set to 80 seconds. Subsequently, running water washing with ultrapure water was carried out for 1 minute, and then drying was performed. Using an exposure machine (using "MPA-600FA" of Canon Inc.: ultra-high pressure mercury lamp), the coating film was exposed over the entire surface in such a manner that the cumulative exposure dose was 300 mJ / cm 2 The exposed substrate was heated at 230 °C for 30 minutes in a clean oven, thereby forming a hardened film on the ITO substrate. Subsequently, an aluminum electrode pattern was formed on the hardened film by vapor deposition method to fabricate a sample for dielectric constant measurement. For the substrate having the electrode pattern, using an electrode ("HP16451B" of Yokogawa-Hewlett Packard) and a precision (Precision) inductance-capacitance-resistance (LCR) meter ("HP4284A" of Yokogawa-Hewlett Packard), the relative dielectric constant was measured at a frequency of 10 kHz.

[0298] (Evaluation criteria)

[0299] AA: Less than 3.1

[0300] A: 3.1 or more and less than 3.4

[0301] B: 3.4 or more and less than 3.7

[0302] C: 3.7 or more

[0303] <Chemical resistance>

[0304] Immerse the cured film produced in the evaluation of the radiation sensitivity in N-methyl-2-pyrrolidone heated to 65 °C for 6 minutes. After immersion, perform running water washing of the coating film with ultrapure water for 5 seconds and dry it. Use a stylus-type film thickness gauge to measure the film thickness of the treated cured film. Calculate the N-methyl-2-pyrrolidone swelling rate (%) according to the following formula and evaluate the chemical resistance according to the following criteria.

[0305] N-methyl-2-pyrrolidone swelling rate (%) = (P / Q - 1) × 100

[0306] 〔In the formula, P represents the remaining film after immersion (μm), and Q represents the remaining film before immersion (μm)〕

[0307] (Evaluation criteria)

[0308] AA: Less than 2%

[0309] A: 2% or more and less than 4%

[0310] B: 4% or more and less than 6%

[0311] C: 6% or more

[0312] [Table 3]

[0313]

[0314] As shown in Table 3, as practical properties, any one of the radiation sensitivity, melt flow resistance, relative dielectric constant, and chemical resistance of the radiation-sensitive compositions of Examples 1 to 16 is good, and a balance of various properties is achieved. In contrast, in Comparative Examples 1 to 6, there is an evaluation of "C" in any property, which is worse than that of Examples 1 to 16.

Claims

1. A radiation-sensitive composition containing: A polymer component (A); A quinone diazide compound (B); and A solvent (C). In the radiation-sensitive composition, The polymer component (A) contains, in the same polymer or different polymers: At least one structural unit (I) selected from the group consisting of a structural unit having an acid group and a structural unit derived from maleimide; A structural unit (II) containing an alicyclic epoxy group; and A structural unit (III) derived from a (meth)acrylate having an alicyclic structure. In the structural unit (III), excluding the structural unit (II), The structural unit (II) is 10% by mass or more relative to all the structural units constituting the polymer component (A), The structural unit (III) is 10% by mass or more relative to all the structural units constituting the polymer component (A).

2. The radiation-sensitive composition according to claim 1, wherein the structural unit (II) is represented by the following formula (II-1), formula (II-2), or formula (II-3). In formula (II-1) to formula (II-3), R 1 are each independently a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; L 1 Each is independently a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms; n is an integer from 1 to 5; k1 is 0 or 1; X 1 are each independently a hydroxyl group, a halogen atom, a cyano group, a nitro group, an alkyl group, or an alkoxy group; a1 is an integer from 0 to 3; when a1 is 2 or more, multiple Xs 1 are the same as or different from each other.

3. The radiation-sensitive composition according to claim 1, wherein the alicyclic structure is a monocyclic alicyclic structure.

4. The radiation-sensitive composition according to claim 1, wherein the (meth)acrylate having the alicyclic structure is cyclohexyl (meth)acrylate.

5. The radiation-sensitive composition according to claim 1, wherein the polymer component (A) further contains a structural unit (IV) having an alkoxysilyl group.

6. The radiation-sensitive composition according to claim 1, wherein the cured film formed by curing the radiation-sensitive composition has a dielectric constant of less than 3.4 at 10 kHz.

7. A method for manufacturing a cured film, including: A step of coating the radiation-sensitive composition according to any one of claims 1 to 6 on a substrate; A step of removing the solvent from the coated radiation-sensitive composition; A step of irradiating the radiation-sensitive composition after removing the solvent with radiation; A step of developing the radiation-sensitive composition irradiated with the radiation; and A step of thermally curing the developed radiation-sensitive composition.

8. A cured film formed using the radiation-sensitive composition according to any one of claims 1 to 6.

9. The cured film according to claim 8, which is an interlayer insulating film or a planarizing film.

10. A display element including the cured film according to claim 9.

11. The display element according to claim 10, for organic electroluminescence.

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