Resin composition, method for producing cured product, cured product, and electronic component

Abstract

This resin composition contains a polyimide precursor that includes a polymerizable unsaturated bond, that has a structural unit represented by general formula (1), and that satisfies the following conditions A and B. In the formula, X represents a tetravalent organic group, Y represents a divalent organic group, and R1 and R2 each independently represent a hydrogen atom or a monovalent organic group.　Condition A: More than 70 mol% of X is a tetravalent organic group X1 including a biphenyl structure. Condition B: More than 50 mol% of Y is a divalent organic group Y1 including a biphenyl structure.

Description

Resin composition, method for producing cured product, cured product, and electronic component

[0001] The present disclosure relates to a resin composition, a method for producing a cured product, a cured product, and an electronic component.

[0002] Polyimide resins, which have excellent heat resistance as well as electrical and mechanical properties, are widely used as materials for resin films used as passivation films, interlayer insulating films, etc. in electronic components. For example, a resin composition containing a polyimide resin or a precursor thereof that has been given photosensitivity so that a polyimide resin film can be formed into a pattern has been proposed (see, for example, Patent Document 1).

[0003] Patent Document 1: JP 2021-85977 A

[0004] As the structures of electronic components become more complex, elements included in electronic components are more susceptible to stress, strain, and the like caused by the expansion and contraction of resin films. In order to suppress the expansion and contraction of resin films, it is desirable for the resin film to have a lower thermal expansion coefficient. Furthermore, it is desirable for the resin film to have a higher glass transition temperature, which is the turning point at which the increase in the thermal expansion coefficient of the resin film becomes significant. Furthermore, it is desirable for the resin film to have good resolution when exposing it to light to form a pattern.

[0005] In view of the above circumstances, an object of one embodiment of the present disclosure is to provide a resin composition that can yield a cured product having a low thermal expansion coefficient, a high glass transition temperature, and excellent resolution. Another embodiment of the present disclosure is to provide a method for producing a cured product using the resin composition, the cured product, and an electronic component.

[0006] Specific means for achieving the above object are as follows: <1> A resin composition containing a polyimide precursor that contains a polymerizable unsaturated bond, has a structural unit represented by the following general formula (1), and satisfies the following conditions A and B: Condition A: More than 70 mol % of X are tetravalent organic groups X1 containing a biphenyl structure; and Condition B: More than 50 mol % of Y are divalent organic groups Y1 containing a biphenyl structure. (wherein X represents a tetravalent organic group, Y represents a divalent organic group, and R １ and R ２each independently represents a hydrogen atom or a monovalent organic group.) <2> The resin composition according to <1>, wherein the divalent organic group Y1 includes a biphenyl structure having a substituent. <3> The resin composition according to <2>, wherein the substituent includes an unsubstituted alkyl group. <4> The polymerizable unsaturated bond is １ or R ２ <1> The resin composition according to any one of <1> to <3>, wherein at least one of the monovalent organic groups represented by the following formula (I) is contained in at least one of the monovalent organic groups represented by the following formula (I). <5> The resin composition according to any one of <1> to <4>, further comprising a photopolymerization initiator. <6> A method for producing a cured product, comprising irradiating the resin composition according to any one of <1> to <5> with actinic rays, and heating the resin composition that has been irradiated with actinic rays. <7> A method for producing the cured product according to <6>, further comprising removing a portion of the resin composition that has been irradiated with actinic rays. <8> A cured product of the resin composition according to any one of <1> to <5>. <9> An electronic component, comprising the cured product according to <8>.

[0007] According to one embodiment of the present disclosure, there is provided a resin composition that can give a cured product having a low thermal expansion coefficient, a high glass transition temperature, and excellent resolution. According to another embodiment of the present disclosure, there are provided a cured product obtained using the resin composition, a method for producing the cured product, and an electronic component.

[0008] 1A to 1C are diagrams illustrating a manufacturing process for an electronic component according to an embodiment of the present disclosure.

[0009] Modes for carrying out the present disclosure are described in detail below. However, the present disclosure is not limited to the following embodiments. In the present disclosure, components (including elementary steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present disclosure. In the present disclosure, the term "process" includes not only processes that are independent of other processes, but also processes that cannot be clearly distinguished from other processes as long as the purpose of the process is achieved. In the present disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in the present disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described in the present disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. In the present disclosure, each component may contain multiple corresponding substances. When a composition contains multiple substances corresponding to each component, the content or amount of each component refers to the total content or amount of the multiple substances present in the composition, unless otherwise specified. In this disclosure, the terms "layer" and "film" include cases where the layer or film is formed over the entire area when the layer or film is observed, as well as cases where the layer or film is formed only in a portion of the area. In this disclosure, the thickness of a layer or film is determined by measuring the thickness at five points on the layer or film in question and calculating the arithmetic mean value. The thickness of a layer or film can be measured using a micrometer or the like. In this disclosure, if the thickness of a layer or film can be measured directly, it is measured using a micrometer. On the other hand, when measuring the thickness of a single layer or the total thickness of multiple layers, it may be measured by observing the cross-section of the target object using an electron microscope.

[0010] In the present disclosure, the term "(meth)acrylic group" refers to an "acrylic group" and a "methacrylic group," "(meth)acrylate" refers to an "acrylate" and a "methacrylate," and "(meth)acryloyl" refers to an "acryloyl" and a "methacryloyl." In the present disclosure, when a functional group has a substituent, the number of carbon atoms in the functional group refers to the total number of carbon atoms including the number of carbon atoms in the substituent. When embodiments are described in the present disclosure with reference to drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. Furthermore, the sizes of components in each drawing are conceptual, and the relative size relationships between components are not limited thereto.

[0011] <Resin Composition> The resin composition of the present disclosure includes a polyimide precursor that contains a polymerizable unsaturated bond, has a structural unit represented by the following general formula (1), and satisfies the following conditions A and B. Condition A: More than 70 mol % of X are tetravalent organic groups X1 containing a biphenyl structure. Condition B: More than 50 mol % of Y are divalent organic groups Y1 containing a biphenyl structure.

[0012]

[0013] In general formula (1), X represents a tetravalent organic group, Y represents a divalent organic group, and R １ and R ２ each independently represents a hydrogen atom or a monovalent organic group.

[0014] In the present disclosure, the term "polyimide precursor" refers to at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyamic acid salt, and polyamic acid amide. The polyamic acid ester and polyamic acid amide are compounds in which the hydrogen atoms of at least some of the carboxy groups in a polyamic acid are substituted with monovalent organic groups, and the polyamic acid salt is a compound in which at least some of the carboxy groups in a polyamic acid form a salt structure with a basic compound having a pH of over 7.

[0015] The polyimide precursor undergoes an imidization reaction upon heating to form a polyimide resin. In the present disclosure, the term "polyimide resin" refers to a polymer compound containing an imide skeleton in all or part of the resin skeleton.

[0016] In the present disclosure, the term "biphenyl structure" refers to a structure in which two benzene rings are bonded by a single bond. The benzene ring constituting the biphenyl structure may or may not have a substituent.

[0017] Hereinafter, a polyimide precursor that contains a polymerizable unsaturated bond, has a structural unit represented by general formula (1), and satisfies conditions A and B will also be referred to as a "specific polyimide precursor."

[0018] When the specific polyimide precursor satisfies condition A, 75 mol % or more, 80 mol % or more, or 85 mol % or more of X may be the tetravalent organic group X1. When the specific polyimide precursor satisfies condition A, 100 mol %, 99 mol % or less, or 95 mol % or less of X may be the tetravalent organic group X1.

[0019] When the specific polyimide precursor satisfies condition B, 55 mol % or more, 60 mol % or more, 70 mol % or more, 80 mol % or more, or 85 mol % or more of X may be the divalent organic group Y1. When the specific polyimide precursor satisfies condition B, 100 mol %, 99 mol % or less, or 95 mol % or less of X may be the divalent organic group Y1.

[0020] In the specific polyimide precursor, the total proportion of the tetravalent organic group X1 and the divalent organic group Y1 to the total of the tetravalent organic group represented by X and the divalent organic group represented by Y in general formula (1) may be 70 mol or more, 75 mol or more, 80 mol or more, or 85 mol or more. This proportion may be 100 mol%, 99 mol% or less, or 95 mol% or less.

[0021] The structure of the tetravalent organic group X1 contained in the specific polyimide precursor is not particularly limited as long as it contains a biphenyl structure. The tetravalent organic group X1 contained in the specific polyimide precursor may be of one type or two or more types. The biphenyl structure contained in the tetravalent organic group X1 may or may not have a substituent, and preferably does not have a substituent.

[0022] The structure of the tetravalent organic group X1 may be a structure represented by the following general formula (X1).

[0023]

[0024] In general formula (X1), R each independently represents a monovalent substituent, n represents the number of R selected from 0 to 3, and * represents a bonding position. When the structure represented by general formula (X1) has two or more monovalent substituents, the two or more monovalent substituents may be the same or different.

[0025] Examples of the monovalent substituent include an alkyl group, a fluorine atom, a halogenated alkyl group, a hydroxyl group, and an amino group. The alkyl group or halogenated alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 carbon atom. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a t-butyl group. Specific examples of the halogenated alkyl group include a trifluoroalkyl group such as a trifluoromethyl group. The monovalent substituent is preferably an unsubstituted alkyl group, and more preferably an unsubstituted methyl group.

[0026] The number of Rs represented by n in formula (X1) is preferably 0 or 1, and more preferably 0.

[0027] The structure of the divalent organic group Y1 contained in the specific polyimide precursor is not particularly limited as long as it contains a biphenyl structure. The divalent organic group Y1 contained in the specific polyimide precursor may be of one type or two or more types. The biphenyl structure contained in the divalent organic group Y1 may or may not have a substituent, and preferably has a substituent. The substituent preferably contains an unsubstituted alkyl group, more preferably an unsubstituted methyl group. The structure of the divalent organic group Y1 may be a structure represented by the following general formula (Y1):

[0028]

[0029] In general formula (Y1), R each independently represents a monovalent substituent, n represents the number of R selected from 0 to 4, and * represents a bonding position. When the structure represented by general formula (Y1) has two or more monovalent substituents, the two or more monovalent substituents may be the same or different.

[0030] Examples of the monovalent substituent include an alkyl group, a fluorine atom, a halogenated alkyl group, a hydroxyl group, and an amino group. The alkyl group or halogenated alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 carbon atom. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a t-butyl group. Specific examples of the halogenated alkyl group include a trifluoroalkyl group such as a trifluoromethyl group. The monovalent substituent is preferably an unsubstituted alkyl group, and more preferably an unsubstituted methyl group.

[0031] The number of Rs represented by n in general formula (Y1) is preferably 1 or 2, and more preferably 1. When n in general formula (Y1) is 1 or greater, it is preferable that the position of at least one R is the ortho position relative to the bonding positions of the two benzene rings constituting the biphenyl structure. That is, the structure represented by general formula (Y1) is preferably a structure represented by the following general formula (Y1'):

[0032]

[0033] In general formula (Y1'), R each independently represents a monovalent substituent, n represents the number of R selected from 0 to 3, and * represents a bonding position. In general formula (Y1'), n each independently represents preferably 0 or 1, and more preferably 0. That is, the structure represented by general formula (Y1) is preferably a structure represented by the following general formula (Y1''):

[0034]

[0035] In formula (Y1″), R each independently represents a monovalent substituent, and * represents the bonding position.

[0036] The specific polyimide precursor may contain, as X in general formula (1), a tetravalent organic group (hereinafter also referred to as tetravalent organic group X2) that does not fall under the category of tetravalent organic group X1. The structure of the tetravalent organic group X2 is not particularly limited. For example, the number of carbon atoms in the tetravalent organic group X2 may be 4 to 25, 6 to 20, or 6 to 12. When the specific polyimide precursor contains a tetravalent organic group X2, the specific polyimide precursor may contain only one type of tetravalent organic group X2, or two or more types of tetravalent organic groups X2.

[0037] The tetravalent organic group X2 may contain an aromatic ring. Examples of the aromatic ring include aromatic hydrocarbon groups (for example, aromatic rings having 6 to 20 carbon atoms) and aromatic heterocyclic groups (for example, heterocyclic rings having 5 to 20 atoms), with aromatic hydrocarbon groups being preferred. Examples of the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, and a phenanthrene ring, with benzene rings being preferred. When the tetravalent organic group X2 contains an aromatic ring, each aromatic ring may have a substituent or may be unsubstituted. Examples of the substituent on the aromatic ring include an alkyl group, a fluorine atom, a halogenated alkyl group, a hydroxyl group, and an amino group.

[0038] When the tetravalent organic group X2 contains a benzene ring, the number of benzene rings is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. When the tetravalent organic group X2 contains two or more benzene rings, the benzene rings may be linked via a linking group. Specific examples of the linking group include an alkylene group, a halogenated alkylene group, a carbonyl group, a sulfonyl group, an ether bond (—O—), a sulfide bond (—S—), a silylene bond (—Si(R Ａ ) ２ -; Two R's Ａ each independently represents a hydrogen atom, an alkyl group, or a phenyl group; a siloxane bond (—O—(Si(R Ｂ ) ２ -O-) ｎ ;Two R's Ｂeach independently represents a hydrogen atom, an alkyl group, or a phenyl group, and n represents an integer of 1 or 2 or greater. ) and composite linking groups combining two or more of these linking groups. Furthermore, a five- or six-membered ring containing a linking group may be formed between two benzene rings.

[0039] From the viewpoint of adjusting the physical properties of a cured product obtained from the resin composition, the tetravalent organic group X2 may have a structure in which two or more benzene rings are linked via an ether bond, or a structure in which two or more benzene rings having a substituent are linked via a single bond or an ether bond. The substituent is preferably an alkyl group, more preferably a methyl group.

[0040] The specific polyimide precursor may contain, as Y in general formula (1), a divalent organic group that does not fall under the category of the divalent organic group Y1 (hereinafter also referred to as a divalent organic group Y2). The structure of the divalent organic group Y2 is not particularly limited. For example, the divalent organic group Y2 may have 4 to 25, 6 to 20, or 6 to 12 carbon atoms. When the specific polyimide precursor contains a divalent organic group Y2, the specific polyimide precursor may contain only one type of divalent organic group Y2, or two or more types of divalent organic groups Y2.

[0041] The divalent organic group Y2 may contain an aromatic ring. Examples of the aromatic ring include aromatic hydrocarbon groups (for example, aromatic rings having 6 to 20 carbon atoms) and aromatic heterocyclic groups (for example, heterocyclic rings having 5 to 20 atoms), with aromatic hydrocarbon groups being preferred. Examples of the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, and a phenanthrene ring, with a benzene ring being preferred. When the divalent organic group Y2 contains an aromatic ring, each aromatic ring may have a substituent or may be unsubstituted. Examples of the substituent on the aromatic ring include an alkyl group, a fluorine atom, a halogenated alkyl group, a hydroxyl group, and an amino group.

[0042] When the divalent organic group Y2 contains a benzene ring, the number of benzene rings is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. When the divalent organic group Y2 contains two or more benzene rings, the benzene rings may be linked via a linking group. Specific examples of the linking group include an alkylene group, a halogenated alkylene group, a carbonyl group, a sulfonyl group, an ether bond (—O—), a sulfide bond (—S—), a silylene bond (—Si(R Ａ ) ２ -; Two R's Ａ each independently represents a hydrogen atom, an alkyl group, or a phenyl group; a siloxane bond (—O—(Si(R Ｂ ) ２ -O-) ｎ ;Two R's Ｂ each independently represents a hydrogen atom, an alkyl group, or a phenyl group, and n represents an integer of 1 or 2 or greater. ) and composite linking groups combining two or more of these linking groups. Furthermore, a five- or six-membered ring containing a linking group may be formed between two benzene rings.

[0043] From the viewpoint of adjusting the physical properties of a cured product obtained from the resin composition, the divalent organic group Y2 may have a structure in which two or more benzene rings are linked via ether bonds, or a structure in which two or more benzene rings having substituents are linked via single bonds or ether bonds.

[0044] The structures of X and Y in general formula (1) can be adjusted by selecting the type of compound used as a raw material for the specific polyimide precursor. For example, by using a tetracarboxylic acid dianhydride having a structure represented by X and a diamine compound having a structure represented by Y as raw materials for the specific polyimide precursor, a specific polyimide precursor having a structure represented by X and Y can be obtained. The pyromellitic dianhydride and the diamine compound used as raw materials for the specific polyimide precursor may each be used alone or in combination of two or more types. The specific polyimide precursor may be synthesized using a tetracarboxylic acid instead of a tetracarboxylic acid dianhydride.

[0045] By using 3,3',4,4'-biphenyltetracarboxylic dianhydride or a derivative thereof as a raw material for the specific polyimide precursor, it is possible to obtain a specific polyimide precursor containing a tetravalent organic group X1 as X in general formula (1).

[0046] From the viewpoint of adjusting the physical properties of the resin film obtained from the resin composition, 4,4'-oxydiphthalic anhydride or a derivative thereof may further be used as a raw material for the specific polyimide precursor.

[0047] By using 4,4'-diaminobiphenyl (also known as benzidine) or a derivative thereof as a raw material for the specific polyimide precursor, it is possible to obtain a specific polyimide precursor containing a divalent organic group Y1 as Y in general formula (1). A specific example of a derivative of 4,4'-diaminobiphenyl is 2,2'-dimethylbiphenyl-4,4'-diamine.

[0048] From the viewpoint of adjusting the physical properties of the resin film obtained from the resin composition, at least one selected from the group consisting of p-phenylenediamine or a derivative thereof, 4,4'-diaminodiphenyl ether or a derivative thereof, and 1,3-bis(3-aminophenoxy)benzene or a derivative thereof may further be used as a raw material for the specific polyimide precursor.

[0049] The polymerizable unsaturated bond contained in the specific polyimide precursor is represented by R １ or R ２ When the specific polyimide precursor contains a plurality of types of structural units represented by general formula (1), the R １ and R ２ The combinations of R may be the same or different. １ and R ２ The combinations of may be the same or different. For example, １ and R ２ one of them may be a hydrogen atom and the other may be a monovalent organic group, and R １ and R ２ may each be a hydrogen atom, and R１ and R ２ may each be a monovalent organic group.

[0050] R １ or R ２ The monovalent organic group represented by the formula (I) is preferably an aliphatic hydrocarbon group having 1 to 4 carbon atoms, or a monovalent organic group containing a polymerizable unsaturated bond. Specific examples of the aliphatic hydrocarbon group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a t-butyl group, and among these, an ethyl group, an isobutyl group, and a t-butyl group are preferred. Examples of the polymerizable unsaturated bond include carbon-carbon double bonds contained in functional groups such as a vinyl group, an acryloyl group, and a methacryloyl group. The monovalent organic group containing a polymerizable unsaturated bond is preferably a group represented by the following general formula (2):

[0051]

[0052] In general formula (2), R ３ ~R ５ each independently represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 3 carbon atoms; R ｘ represents a divalent linking group.

[0053] R in general formula (2) ３ ~R ５ The carbon number of the aliphatic hydrocarbon group represented by R is 1 to 3, and preferably 1 or 2. ３ ~R ５ Specific examples of the aliphatic hydrocarbon group represented by the formula include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, etc., with a methyl group being preferred.

[0054] R in general formula (2) ３ ~R ５ As a combination of ３ and R ４ is a hydrogen atom, and R ５ is a hydrogen atom or a methyl group. That is, the monovalent organic group represented by general formula (2) preferably contains an acryloyl group or a methacryloyl group.

[0055] R in general formula (2) ｘis a divalent linking group, and is preferably a hydrocarbon group having 1 to 10 carbon atoms. Examples of the hydrocarbon group having 1 to 10 carbon atoms include linear or branched alkylene groups. ｘ The number of carbon atoms is preferably 1 to 10, more preferably 2 to 5, and even more preferably 2 or 3.

[0056] The group represented by formula (2) is preferably a group represented by the following formula (2').

[0057]

[0058] In general formula (2'), R ３ ~R ５ each independently represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 3 carbon atoms; and q represents an integer of 1 to 10.

[0059] In formula (2'), q is an integer of 1 to 10, preferably an integer of 2 to 5, and more preferably 2 or 3.

[0060] The polymerizable unsaturated bond contained in the specific polyimide precursor is R in general formula (1). １ or R ２ When the compound is contained in at least one of the monovalent organic groups represented by １ and R ２ Among them, the proportion of monovalent organic groups containing polymerizable unsaturated bonds is preferably 60 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more. The upper limit of the content is not particularly limited and may be 100 mol%, 95 mol%, or 90 mol%. In an embodiment, the content may be more than 0 mol% and less than 60 mol%.

[0061] The polymerizable unsaturated bond contained in the specific polyimide precursor is R in general formula (1). １ or R ２ When the compound is contained in at least one of the monovalent organic groups represented by １ and R ２Among these, the proportion of groups represented by general formula (2) is preferably 60 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more. The upper limit of the content is not particularly limited and may be 100 mol%. In one embodiment, the content may be more than 0 mol% and less than 60 mol%.

[0062] In the general formula (1), -COOR １ The —COOR group and the —CONH— group are preferably in the ortho position relative to each other. ２ The group and the —CO— group are preferably in the ortho position relative to each other.

[0063] A polyimide precursor having a polymerizable unsaturated bond can be obtained, for example, by the following method (a) or (b): (a) A tetracarboxylic dianhydride is reacted with a compound represented by R—OH to obtain a diester derivative. Then, the diester derivative is subjected to a condensation reaction with a diamine compound. (b) A tetracarboxylic dianhydride is reacted with a diamine compound to obtain a polyamic acid. Then, the polyamic acid is reacted with a compound represented by R—OH to introduce an ester group.

[0064] By using a compound in which R has a polymerizable unsaturated bond as at least a part of the compound represented by R—OH used in the above method, R １ or R ２ It is possible to obtain a polyimide precursor in a state in which a polymerizable unsaturated bond is contained in at least a part of the monovalent organic group represented by the formula:

[0065] The compound represented by R—OH is a group represented by general formula (2) ｘThe compound may be a compound having a hydroxy group bonded to the terminal methylene group of a group represented by general formula (2'), or a compound having a hydroxy group bonded to the terminal methylene group of a group represented by general formula (2'). Specific examples of the compound represented by R-OH include methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, and 4-hydroxybutyl methacrylate, and among these, 2-hydroxyethyl methacrylate (HEMA) and 2-hydroxyethyl acrylate (HEA) are preferred.

[0066] The molecular weight of the specific polyimide precursor is not particularly limited, and for example, the weight average molecular weight is preferably 10,000 to 200,000, more preferably 10,000 to 100,000, and even more preferably 15,000 to 60,000. The weight average molecular weight of the specific polyimide precursor can be measured, for example, by gel permeation chromatography, and can be calculated using a standard polystyrene calibration curve.

[0067] (Polyimide precursor not corresponding to specific polyimide precursor) The resin composition of the present disclosure may contain a polyimide precursor not corresponding to the specific polyimide precursor (hereinafter also referred to as other polyimide precursor). The other polyimide precursor may or may not contain a polymerizable unsaturated bond.

[0068] When the resin composition of the present disclosure contains other polyimide precursors, the proportion of the other polyimide precursors relative to the total of the specific polyimide precursor and the other polyimide precursors may be 30% by mass or less, 20% by mass or less, or 10% by mass or less, and may be 1% by mass or more, 2% by mass or more, or 5% by mass or more.

[0069] (Polyimide Resin) The resin composition of the present disclosure may contain a polyimide resin. Examples of the polyimide resin include polyimide resins having a structural unit represented by the following general formula (X).

[0070]

[0071] In general formula (X), X represents a tetravalent organic group, and Y represents a divalent organic group. In general formula (X), more than 70 mol% of X may be tetravalent organic groups X1 containing a biphenyl structure. In general formula (X), more than 50 mol% of Y may be divalent organic groups Y1 containing a biphenyl structure. Preferred examples of X, X1, Y, and Y1 in general formula (X) are the same as the preferred examples of X, X1, Y, and Y1 in general formula (1) described above.

[0072] When the resin composition of the present disclosure contains a polyimide precursor and a polyimide resin, the proportion of the polyimide resin relative to the total of the polyimide precursor and the polyimide resin may be 30% by mass or less, 20% by mass or less, or 10% by mass or less. The proportion may be 1% by mass or more, 2% by mass or more, or 5% by mass or more. When the resin composition of the present disclosure contains a specific polyimide precursor and another polyimide precursor, the above-mentioned "polyimide precursor" is a concept that includes the specific polyimide precursor and the other polyimide precursor.

[0073] (Other Resins) The resin composition of the present disclosure may contain a resin that does not fall under the category of a polyimide precursor or a polyimide resin (hereinafter also referred to as "other resins"). From the viewpoint of heat resistance, examples of the other resins include novolac resins, acrylic resins, polyethernitrile resins, polyethersulfone resins, epoxy resins, polyethylene terephthalate resins, polyethylene naphthalate resins, and polyvinyl chloride resins. The other resins may be used alone or in combination of two or more.

[0074] When the resin composition of the present disclosure contains other resins, the proportion of the other resins relative to the total of the polyimide precursor, polyimide resin, and other resins (hereinafter also referred to as resin components) may be 30% by mass or less, 20% by mass or less, or 10% by mass or less, and may be 1% by mass or more, 2% by mass or more, or 5% by mass or more.

[0075] (Photopolymerization initiator) The resin composition of the present disclosure may contain a photopolymerization initiator. The photopolymerization initiator may be used alone or in combination of two or more. From the viewpoints of excellent exposure sensitivity and suppressing the occurrence of voids during bonding, it is preferable to contain an oxime-based photopolymerization initiator as the photopolymerization initiator. Specific examples of oxime-based photopolymerization initiators include 1-phenyl-1,2-butanedione-2-(O-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(O-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(O-benzoyl)oxime, and 1,3-diphenylpropanetrione-2-(O-ethoxycarbonyl)oxime. , 1-phenyl-3-ethoxypropanetrione-2-(O-benzoyl)oxime, 1-[4-(phenylthio)phenyl]octane-1,2-dione 2-(O-benzoyloxime), O-acetyl-1-[6-(2-methylbenzoyl)-9-ethyl-9H-carbazol-3-yl]ethanone oxime, 1-[4-(4-hydroxyethyloxy-phenylthio)phenyl]-1,2-propanedione-2-(O-acetyloxime), and the like.

[0076] When the resin composition of the present disclosure contains a photopolymerization initiator, the total amount of the photopolymerization initiator is preferably 0.1 parts by mass to 20 parts by mass, more preferably 1 part by mass to 20 parts by mass, and even more preferably 5 parts by mass to 20 parts by mass, relative to 100 parts by mass of the resin component.

[0077] (Stabilizer) The resin composition of the present disclosure may contain a stabilizer. The stabilizers may be used alone or in combination of two or more.

[0078] Examples of stabilizers include p-methoxyphenol, diphenyl-p-benzoquinone, benzoquinone, hydroquinone, pyrogallol, phenothiazine, resorcinol, ortho-dinitrobenzene, para-dinitrobenzene, meta-dinitrobenzene, phenanthraquinone, N-phenyl-2-naphthylamine, cupferron, 2,5-toluquinone, tannic acid, parabenzylaminophenol, nitrosamines, azo compounds, hindered amine compounds, and hindered phenol compounds.

[0079] When the resin composition of the present disclosure contains a stabilizer, the content of the stabilizer is preferably 0.05 parts by mass to 1.0 parts by mass, and more preferably 0.1 parts by mass to 0.8 parts by mass, per 100 parts by mass of the resin component.

[0080] (Crosslinking Agent) The resin composition of the present disclosure may contain a crosslinking agent. The crosslinking agent may be used alone or in combination of two or more. When the resin composition contains a crosslinking agent, the heat resistance, mechanical properties, and chemical resistance of a cured product formed from the resin composition can be improved. The crosslinking agent may be used alone or in combination of two or more.

[0081] Examples of the crosslinking agent include a compound having two or more groups containing a polymerizable unsaturated bond (hereinafter also referred to as functional groups). From the viewpoint of polymerization reactivity, the functional group is preferably a (meth)acryloyl group or a vinyl group, and more preferably a (meth)acryloyl group.

[0082] Examples of bifunctional crosslinking agents include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, trimethylolpropane diacrylate, tricyclodecane dimethanol diacrylate, and tricyclodecane dimethanol dimethacrylate.

[0083] Examples of trifunctional crosslinking agents include trimethylolpropane triacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, tris-(2-acryloxyethyl)isocyanurate, and tris-(2-methacryloxyethyl)isocyanurate.

[0084] Examples of tetrafunctional or higher crosslinking agents include pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, tetramethylolmethane tetraacrylate, tetramethylolmethane tetramethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, and tetrakisacrylatemethanetetrayltetrakis(methyleneoxyethylene).

[0085] When the resin composition of the present disclosure contains a crosslinking agent, the content of the crosslinking agent is preferably 1 part by mass to 50 parts by mass, more preferably 3 parts by mass to 50 parts by mass, and even more preferably 5 parts by mass to 40 parts by mass, relative to 100 parts by mass of the resin component.

[0086] (Sensitizer) The resin composition of the present disclosure may contain a sensitizer. The sensitizer may be used alone or in combination of two or more. Specific examples of the sensitizer include benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, 4,4'-bis(diethylamino)benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl ketone, dibenzyl ketone, fluorenone, and other benzophenone derivatives.

[0087] When the resin composition of the present disclosure contains a sensitizer, the content of the sensitizer is preferably 0.01 parts by mass to 3 parts by mass, and more preferably 0.1 parts by mass to 1 part by mass, per 100 parts by mass of the resin component.

[0088] (Ultraviolet Absorber) The resin composition of the present disclosure may contain an ultraviolet absorber. When the resin composition contains an ultraviolet absorber, crosslinking of unexposed areas due to diffuse reflection during exposure tends to be suppressed.

[0089] Examples of the ultraviolet absorber include benzotriazole-based compounds, salicylic acid ester-based compounds, benzophenone-based compounds, diphenylacrylate-based compounds, cyanoacrylate-based compounds, diphenylcyanoacrylate-based compounds, benzothiazole-based compounds, azobenzene-based compounds, polyphenol-based compounds, nickel complex salt-based compounds, etc. The ultraviolet absorbers may be used alone or in combination of two or more.

[0090] When the resin composition of the present disclosure contains an ultraviolet absorber, the content of the ultraviolet absorber is preferably 0.05 parts by mass to 5 parts by mass, more preferably 0.1 parts by mass to 3 parts by mass, and even more preferably 0.2 parts by mass to 2 parts by mass, relative to 100 parts by mass of the resin component.

[0091] (Rust inhibitor) The resin composition of the present disclosure may contain a rust inhibitor from the viewpoint of inhibiting corrosion of metals such as copper and copper alloys and inhibiting discoloration of the metals. Examples of the rust inhibitor include azole compounds and purine derivatives. The rust inhibitor may be used alone or in combination of two or more.

[0092] Specific examples of the azole compound include 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, 4-t-butyl-5-phenyl-1H-triazole, 5-hydroxyphenyl-1H-triazole, phenyltriazole, p-ethoxyphenyltriazole, 5-phenyl-1-(2-dimethylaminoethyl)triazole, 5-benzyl-1H-triazole, hydroxyphenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-benzotriazole, and benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)benzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole, and the like.

[0093] Specific examples of purine derivatives include purine, adenine, guanine, hypoxanthine, xanthine, theobromine, caffeine, uric acid, isoguanine, 2,6-diaminopurine, 9-methyladenine, 2-hydroxyadenine, 2-methyladenine, 1-methyladenine, N-methyladenine, N,N-dimethyladenine, 2-fluoroadenine, 9-(2-hydroxyethyl)adenine, guanine oxime, N-(2-hydroxyethyl)adenine, and 8-amino Examples include adenine, 6-amino-8-phenyl-9H-purine, 1-ethyladenine, 6-ethylaminopurine, 1-benzyladenine, N-methylguanine, 7-(2-hydroxyethyl)guanine, N-(3-chlorophenyl)guanine, N-(3-ethylphenyl)guanine, 2-azaadenine, 5-azaadenine, 8-azaadenine, 8-azaguanine, 8-azapurine, 8-azaxanthine, 8-azahypoxanthine, and derivatives thereof.

[0094] When the resin composition of the present disclosure contains a rust inhibitor, the content of the rust inhibitor is preferably 0.01 parts by mass to 10 parts by mass, more preferably 0.1 parts by mass to 5 parts by mass, and even more preferably 0.5 parts by mass to 3 parts by mass, relative to 100 parts by mass of the resin component.

[0095] (Thermal Radical Generator) The resin composition of the present disclosure may contain a thermal radical generator from the viewpoint of improving the physical properties of the cured product. The thermal radical generator may be used alone or in combination of two or more.

[0096] Specific examples of the thermal radical generator include ketone peroxides such as methyl ethyl ketone peroxide, peroxyketals such as 1,1-di(t-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di(t-hexylperoxy)cyclohexane, and 1,1-di(t-butylperoxy)cyclohexane, hydroperoxides such as 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, p-menthane hydroperoxide, and diisopropylbenzene hydroperoxide, and di-t-butyl peroxide. Examples of the thermal polymerization initiator include diacyl peroxides such as alkyl peroxide, dilauroyl peroxide, and dibenzoyl peroxide, peroxydicarbonates such as di(4-t-butylcyclohexyl)peroxydicarbonate and di(2-ethylhexyl)peroxydicarbonate, peroxy esters such as t-butylperoxy-2-ethylhexanoate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxybenzoate, and 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, and bis(1-phenyl-1-methylethyl)peroxide. One type of thermal polymerization initiator may be used alone, or two or more types may be used in combination.

[0097] When the resin composition of the present disclosure contains a thermal radical generator, the content of the thermal radical generator may be 0.1 parts by mass to 20 parts by mass, 1 part by mass to 15 parts by mass, or 1 part by mass to 10 parts by mass relative to 100 parts by mass of the resin component.

[0098] (Antioxidant) The resin composition of the present disclosure may contain an antioxidant. When the resin composition of the present disclosure contains an antioxidant, oxidation of the electrode during an insulation reliability test can be suppressed. The antioxidant may be used alone or in combination of two or more.

[0099] Specific examples of the antioxidant include hindered phenol compounds, N,N'-bis[2-[2-(3,5-di-tert-butyl-4-hydroxyphenyl)ethylcarbonyloxy]ethyl]oxamide, N,N'-bis-3-(3,5-di-tert-butyl-4'-hydroxyphenyl)propionylhexamethylenediamine, 1,3,5-tris(3-hydroxy-4-tert-butyl-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid. One type of antioxidant may be used alone, or two or more types may be used in combination.

[0100] When the resin composition of the present disclosure contains an antioxidant, the content of the antioxidant is preferably 0.1 parts by mass to 20 parts by mass, more preferably 0.1 parts by mass to 10 parts by mass, and even more preferably 0.1 parts by mass to 5 parts by mass, relative to 100 parts by mass of the resin component.

[0101] (Solvent) The resin composition of the present disclosure may contain a solvent. The type of solvent is not particularly limited, and known solvents can be used. Specific examples include ester solvents, ether solvents, ketone solvents, hydrocarbon solvents, aromatic hydrocarbon solvents, sulfoxide solvents, carbonate solvents other than propylene carbonate or ethylene carbonate, and urea solvents. The solvent may be used alone or in combination of two or more. When the resin composition contains a solvent, the content of the solvent can be adjusted according to the desired viscosity of the resin composition, etc.

[0102] <Method for producing a cured product> The method for producing a cured product of the present disclosure includes irradiating the resin composition of the present disclosure with actinic rays (hereinafter also referred to as exposure treatment), and heating the resin composition irradiated with actinic rays (hereinafter also referred to as heat treatment).

[0103] The resin composition used in the above method contains a specific polyimide precursor, and therefore, when the resin composition is irradiated with actinic rays, a polymerization reaction of the unsaturated bonds contained in the specific polyimide precursor occurs, resulting in a decrease in the solubility in a developer.

[0104] In the exposure treatment, the resin composition is irradiated with actinic rays. The conditions for the exposure treatment are not particularly limited as long as they are conditions that cause a polymerization reaction of the unsaturated bonds contained in the specific polyimide precursor. Examples of actinic rays used in the exposure treatment include ultraviolet rays such as i-rays, visible light, and radiation, with i-rays being preferred. From the viewpoint of promoting the polymerization reaction of the unsaturated bonds contained in the specific polyimide precursor, the exposure treatment of the resin composition is preferably performed on a layer of the resin composition formed on a substrate (hereinafter also referred to as a resin composition layer). The method for forming the resin composition layer on the substrate is not particularly limited. For example, a method in which the resin composition is applied to the substrate by spin coating may be used. After application of the resin composition, a drying treatment may be performed to remove the solvent contained in the resin composition layer. The drying treatment may be, for example, a treatment in which the resin composition layer is heated in an oven, a hot plate, or the like.

[0105] The substrate may be a glass substrate, a semiconductor substrate such as a Si substrate (silicon wafer), or a TiO ２ Substrate, SiO ２ Examples of the substrate include a metal oxide insulator substrate, a silicon nitride substrate, a copper substrate, and a copper alloy substrate.

[0106] The thickness of the resin composition layer formed on the substrate is not particularly limited and can be selected in consideration of the thickness of the final cured product. The thickness of the resin composition layer immediately after being formed by applying the resin composition on the substrate may be selected, for example, from the range of 5 μm to 100 μm.

[0107] The exposure treatment may be carried out by a method of irradiating the resin composition with actinic rays in a pattern. By carrying out the exposure treatment in a pattern, in the region of the resin composition irradiated with actinic rays (exposed portion), a polymerization reaction of the unsaturated bonds contained in the specific polyimide precursor proceeds, making it difficult to remove with a developer. In the region of the resin composition not irradiated with actinic rays (unexposed portion), a polymerization reaction of the unsaturated bonds contained in the specific polyimide precursor does not proceed, and a state in which it is easily removed with a developer is maintained.

[0108] The method of the present disclosure may also include removing a portion of the resin composition irradiated with actinic rays (hereinafter also referred to as a developing step). In the developing process, for example, the unexposed portion of the resin composition after the exposure process is removed by contacting it with a developer. Therefore, by performing the exposure process on the resin composition in a pattern and then performing the developing process, a resin composition in which the exposed portion remains in a pattern can be obtained. The developer can be any developer that can remove the unexposed portion of the resin composition without any particular limitation. For example, an organic solvent that can dissolve the unexposed portion of the resin composition can be used.

[0109] In the heat treatment, the resin composition that has been subjected to exposure treatment and, if necessary, development treatment is heated. The heat treatment causes the moiety introduced into the specific polyimide precursor via an ester bond to be eliminated, resulting in imidization. The conditions for the heat treatment are not particularly limited as long as they result in imidization of the polyimide precursor and the formation of a polyimide resin. For example, the heat treatment temperature can be selected from the range of 80°C to 450°C. From the viewpoint of sufficiently promoting imidization of the polyimide precursor to obtain a cured product with excellent heat resistance, the heat treatment temperature is preferably 100°C or higher, more preferably 150°C or higher, and even more preferably 200°C or higher. From the viewpoint of suppressing deterioration of the cured product obtained by the heat treatment, the heat treatment temperature is preferably 400°C or lower, more preferably 350°C or lower, and even more preferably 300°C or lower.

[0110] The heat treatment time is not particularly limited, but is preferably 5 hours or less, and more preferably 30 minutes to 3 hours. The heat treatment may be performed in air or in an inert atmosphere such as nitrogen, but is preferably performed in an inert atmosphere such as nitrogen from the viewpoint of suppressing oxidation of the cured product obtained from the resin composition.

[0111] <Cured Product> The cured product of the present disclosure is a cured product of the resin composition of the present disclosure. The resin composition of the present disclosure contains a polyimide precursor. Therefore, by heat-treating the resin composition of the present disclosure, a cured product of the resin composition can be obtained. More specifically, by heat-treating the resin composition, imidization (dehydration ring-closing reaction) of the polyimide precursor occurs, converting it into a polyimide resin, and thereby curing the resin composition. In other words, the cured product of the present disclosure contains polyimide, which is an imidized product of the polyimide precursor.

[0112] Furthermore, the polyimide precursor contained in the resin composition of the present disclosure contains a polymerizable unsaturated bond. Therefore, the cured product of the present disclosure may be a patterned cured product (patterned cured product) obtained by subjecting the resin composition before heat treatment to a patterned exposure treatment and development treatment. The cured product of the present disclosure may be in the form of a film. When the cured product is in the form of a film, its thickness is not particularly limited and may be selected, for example, from the range of 1 μm to 30 μm.

[0113] The cured product of the present disclosure can be used, for example, as a resin film for use in electronic components, such as a passivation film, a buffer coat film, an interlayer insulating film, a cover coat layer, and a surface protection film.

[0114] <Electronic Component> The electronic component of the present disclosure includes the cured product of the present disclosure described above. The electronic component includes, for example, the cured product of the present disclosure as an interlayer insulating film, a cover coat layer, a surface protective film, a passivation film, a buffer coat film, or the like.

[0115] An example of a manufacturing process for a semiconductor device, which is an electronic component according to the present disclosure, will be described with reference to the drawings. Figure 1 is a diagram illustrating a manufacturing process for a semiconductor device with a multilayer wiring structure, which is an electronic component according to an embodiment of the present disclosure. In Figure 1, a semiconductor substrate 1, such as a Si substrate, having circuit elements is covered with a protective film 2, such as a silicon oxide film, except for predetermined portions of the circuit elements, and a first conductor layer 3 is formed on the exposed circuit elements. An interlayer insulating film 4 is then formed on the semiconductor substrate 1.

[0116] Next, a photosensitive resin layer 5 such as a chlorinated rubber or phenol novolac resin is formed on the interlayer insulating film 4, and windows 6A are formed by known photoetching techniques so that predetermined portions of the interlayer insulating film 4 are exposed.

[0117] The interlayer insulating film 4 where the window 6A is exposed is selectively etched to provide a window 6B. Next, the photosensitive resin layer 5 is removed using an etching solution that corrodes the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed through the window 6B.

[0118] Furthermore, a second conductor layer 7 is formed using a known photolithography technique, and electrically connected to the first conductor layer 3. When forming a multilayer wiring structure having three or more layers, the above steps can be repeated to form each layer.

[0119] Next, the resin composition of the present disclosure is used to open windows 6C by pattern exposure, and a surface protective film 8 is formed. The surface protective film 8 protects the second conductor layer 7 from external stress, alpha rays, etc., and the resulting semiconductor device has excellent reliability. In the above example, the interlayer insulating film 4 can also be formed using the resin composition of the present disclosure.

[0120] The present disclosure will be described in more detail below based on examples and comparative examples, but the present disclosure is not limited to the following examples.

[0121] (Synthesis of specific polyimide precursor) A solution was obtained by dissolving the tetracarboxylic dianhydride (7.07 g) shown below and the diamine compound (4.12 g) shown below in N-methyl-2-pyrrolidone (30 g). The obtained solution was stirred at 30°C for 4 hours to obtain a polyamic acid solution. Trifluoroacetic anhydride (9.45 g) was added to the polyamic acid solution at room temperature (25°C). Next, 2-hydroxyethyl methacrylate (7.08 g) was added, and the mixture was stirred at 45°C for 10 hours to obtain a reaction solution. This reaction solution was added dropwise to distilled water, and the precipitate was collected by filtration and dried under reduced pressure to obtain a specific polyimide precursor.

[0122] The tetracarboxylic dianhydride used in the synthesis of the specific polyimide precursor was a mixture containing the following two compounds in the molar ratio shown in Table 1. sBPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride, a compound containing a tetravalent organic group X1 ODPA: 4,4'-oxydiphthalic anhydride, a compound containing a tetravalent organic group X2

[0123] The diamine compound used in the synthesis of the specific polyimide precursor was a mixture containing the following two compounds in the molar ratio shown in Table 1. DMAP: 2,2'-dimethylbiphenyl-4,4'-diamine, a compound containing a divalent organic group Y1 PPD: p-phenylenediamine, a compound containing a divalent organic group Y2

[0124] (Measurement of Weight-Average Molecular Weight) The weight-average molecular weight (Mw) of the obtained specific polyimide precursor is shown in Table 1. The weight-average molecular weight of the specific polyimide precursor was determined in terms of standard polystyrene using gel permeation chromatography (GPC). The results are shown in Table 1. Specifically, a solution obtained by dissolving the specific polyimide precursor (0.5 mg) in 1 mL of a solvent [tetrahydrofuran (THF) / dimethylformamide (DMF) = 1 / 1 (volume ratio)] was used, and the measurement was carried out under the following conditions.

[0125] (Measurement conditions) Measuring device: Shimadzu Corporation SPD-M20A Pump: Shimadzu Corporation LC-20AD Column oven: Shimadzu Corporation: CTO-20A Measurement conditions: Column Gelpack GL-S300MDT-5 x 2 Eluent: THF / DMF = 1 / 1 (volume ratio) LiBr (0.03 mol / L), H ３ P.O. ４ (0.06 mol / L) Flow rate: 1.0 mL / min, detector: UV 270 nm, column temperature: 40°C Standard polystyrene: Tosoh TSKgel standard polystyrene Type F-1, F-4, F-20, F-80 and A-2500 Calibration curve prepared

[0126] (Measurement of Esterification Ratio) The esterification ratio of the specific polyimide precursor (the ratio of ester groups reacted with HEMA to the total of ester groups reacted with HEMA and carboxy groups unreacted with HEMA) was calculated by performing NMR measurement under the following conditions. The esterification ratio was 70 mol % to 90 mol % for each specific polyimide precursor.

[0127] (Measurement conditions) Measuring equipment: Bruker Biospin AV400M Magnetic field strength: 400 MHz Reference substance: tetramethylsilane (TMS) Solvent: dimethyl sulfoxide (DMSO)

[0128] (Preparation of Resin Composition) The following components were mixed to prepare resin compositions of Examples and Comparative Examples. Specific polyimide precursor: 34.0 g; γ-butyrolactone (GBL) as a solvent: 56.0 g; 1,4,4-trimethyl-2,3-diazabicyclo[3.2.2]non-2-ene-2,3-dioxide (Taobn) as a polymerization inhibitor: 0.1 g; TEGDMA (triethylene glycol dimethacrylate) as a crosslinking agent: 5.1 g; 1-[4-(phenylthio)phenyl]octane-1,2-dione=2-(O-benzoyloxime (Irgacure OXE1, BASF) as a photopolymerization initiator: 0.7 g; and 3-glycidoxypropyltrimethoxysilane (KBM-403, Shin-Etsu Silicones) as an adhesion promoter: 1.0 g.

[0129] (Measurement of Glass Transition Temperature and Thermal Expansion Coefficient) The resin composition was spin-coated on a silicon wafer to form a film having a thickness of 10 μm after curing. This film was exposed to light at an exposure dose of 40 mJ / cm using MA / BA-8 manufactured by SUSS MicroTec K.K. ２ The wafer was exposed to light through a mask at 1000 W / m. 30 minutes after exposure, the wafer was paddle-developed with cyclopentanone and then rinsed with propylene glycol monomethyl ether acetate to obtain a patterned resin film. The obtained patterned resin film was heated at 280°C for 2 hours in a nitrogen atmosphere using a vertical diffusion furnace manufactured by Koyo Thermo Systems, to obtain a polyimide film made of a cured product of the resin composition. A silicon wafer having a polyimide film formed on its surface was immersed in a 4.9% by mass hydrofluoric acid solution, and the polyimide film was peeled off from the silicon wafer to obtain a polyimide film with an average thickness of 10 μm.

[0130] The resulting polyimide film was cut into a 5 mm width to prepare a sample. Using a thermomechanical analyzer (TMA7100, manufactured by Hitachi High-Tech Science Corporation) and a tensile jig, the elongation (expansion) of the sample was measured in the temperature range of 50°C to 350°C under the following conditions: initial sample length: 20 mm, heating rate: 5°C / min, and load: 10 g. The glass transition temperature (Tg, °C) was determined using the tangent method from the curve of sample elongation versus temperature obtained by the above method. When there were multiple glass transition temperatures, the lowest value among them was taken as the glass temperature. Furthermore, the thermal expansion coefficient (CTE, ppm / K) of the sample was calculated using the following formula: [Sample length change (mm) in the temperature range of 50°C to 100°C] ÷ [Initial sample length (mm)] ÷ [Temperature change (50K)] = CTE (ppm / K).

[0131] (Evaluation of Glass Transition Temperature) The measured values ​​of glass transition temperature were evaluated according to the following criteria. The results are shown in Table 1. A: Glass transition temperature is 300°C or higher. B: Glass transition temperature is 250°C or higher and lower than 300°C. C: Glass transition temperature is lower than 250°C.

[0132] (Evaluation of Thermal Expansion Coefficient) The measured values ​​of the thermal expansion coefficient were evaluated according to the following criteria. The results are shown in Table 1. A: The thermal expansion coefficient is less than 30.0 ppm / K. B: The thermal expansion coefficient is 30.0 ppm / K or more and less than 45.0 ppm / K. C: The thermal expansion coefficient is 45.0 ppm / K or more.

[0133] (Evaluation of Resolution) The resin composition was spin-coated onto a silicon wafer, dried at 110°C for 2 minutes, and then further dried at 110°C for 2 minutes to form a photosensitive resin film with a thickness of 9 μm to 11 μm. The resulting photosensitive resin film was immersed in cyclopentanone and the development time was set to twice the time required for complete dissolution. In addition, the photosensitive resin film prepared in the same manner as above was subjected to a development using an i-line stepper NES2W-i06 (manufactured by Nikon Corporation) at 100 mJ / cm. ２ ~1100mJ / cm ２ in the energy range (100 mJ / cm ２ The exposure was performed at intervals of 1 μm to 100 μm. The exposure was performed using a photomask for via formation with a diameter of 1 μm to 100 μm. The exposed resin film was subjected to puddle development using cyclopentanone for a set development time. After that, the resin film was rinsed with propylene glycol monomethyl ether acetate (PGMEA) to obtain a patterned resin film having via-shaped openings. The patterned resin film was heated in an inert gas oven (manufactured by JTEKT Corporation) under conditions of 280°C in a nitrogen atmosphere for 2 hours to obtain a polyimide film (film thickness 6 μm) having a via-shaped opening pattern.

[0134] The polyimide film was observed using an optical microscope, and the diameter D of the smallest opening among those in which 55% or more of the via area in the photomask exposed the substrate surface was measured. The resolution of the polyimide film was evaluated according to the following criteria. The results are shown in Table 1. A: Diameter D is less than 8 μm B: Diameter D is 8 μm or more but less than 15 μm C: Diameter D is 15 μm or more

[0135]

[0136] As shown in Table 1, the polyimide films of the comparative examples obtained using resin compositions containing no polyimide precursor satisfying the conditions of the present disclosure were evaluated as "C" in at least one of the glass transition temperature, thermal expansion coefficient, and resolution. In contrast, the polyimide films of the examples obtained using resin compositions containing a polyimide precursor satisfying the conditions of the present disclosure were evaluated as "A" or "B" in all of the glass transition temperature, thermal expansion coefficient, and resolution.

Claims

1. A resin composition comprising a polyimide precursor that contains a polymerizable unsaturated bond, has a structural unit represented by the following general formula (1), and satisfies the following conditions A and B: Condition A: More than 70 mol% of X are tetravalent organic groups X1 containing a biphenyl structure; and Condition B: More than 50 mol% of Y are divalent organic groups Y1 containing a biphenyl structure. (wherein X represents a tetravalent organic group, Y represents a divalent organic group, and R １ and R ２ each independently represents a hydrogen atom or a monovalent organic group.

2. The resin composition according to claim 1, wherein the divalent organic group Y1 contains a biphenyl structure having a substituent.

3. The resin composition according to claim 2, wherein the substituent comprises an unsubstituted alkyl group.

4. The polymerizable unsaturated bond is R １ or R ２ The resin composition according to claim 1, wherein the aryl group is a methyl group, and the aryl group is a methyl group.

5. The resin composition according to claim 1, further comprising a photopolymerization initiator.

6. A method for producing a cured product, comprising: irradiating the resin composition according to any one of claims 1 to 5 with actinic rays; and heating the resin composition that has been irradiated with actinic rays.

7. The method for producing a cured product according to claim 6, further comprising removing a portion of the resin composition that has been irradiated with actinic rays.

8. A cured product of the resin composition according to any one of claims 1 to 5.

9. An electronic component comprising the cured product according to claim 8.

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