JP7782317B2 - Photosensitive resin composition - Google Patents

Description

The present invention relates to a photosensitive resin composition, a resin film obtained from the composition, a photosensitive resist film using the composition, a method for producing a substrate with a cured relief pattern, and a semiconductor device having a cured relief pattern.

Polyimide resins, which combine excellent heat resistance with excellent electrical and mechanical properties, have traditionally been used as insulating materials for electronic components, and for passivation films, surface protection films, and interlayer insulating films for semiconductor devices. Among these polyimide resins, those supplied in the form of photosensitive polyimide precursors can easily form heat-resistant relief pattern coatings by applying the precursor, exposing it to light, developing it, and subjecting it to a thermal imidization process involving curing. Such photosensitive polyimide precursors have the advantage of enabling significant process reductions compared to conventional non-photosensitive polyimide resins.

Patent Documents 1 and 2 propose photosensitive resin compositions containing polyamic acid or polyimide using diamines having a (meth)acryloyloxy group.
Furthermore, Patent Document 3 proposes a photosensitive resin composition that can obtain sufficient developability and can form a thick film with good resolution by using the composition, the photosensitive resin composition including (A) a polyamic acid having an alkylene group having 5 to 20 carbon atoms in its main chain and an ethylenically unsaturated group in its diamine residue, (B) a photopolymerizable compound, and (C) a photopolymerization initiator.

Furthermore, increasing the thickness and modulus of elasticity of passivation films, surface protection films, interlayer insulating films, etc. of semiconductor devices increases stress, which can lead to greater warping of semiconductor wafers and problems during transportation and wafer fixation. Therefore, there is a need for the development of polyimide resins with low residual stress. One method for reducing the residual stress in polyimide resins is to give the polyimide molecular chains a rigid skeleton in order to bring the thermal expansion coefficient of polyimide closer to that of a silicon wafer (see, for example, Patent Document 4).

Japanese Patent Application Laid-Open No. 2000-347404 Special Publication No. 2012-516927 JP 2009-251451 A Japanese Patent Application Publication No. 5-295115

In recent years, semiconductor devices have been using increasingly higher frequency electrical signals due to the need to transmit and process large amounts of information at high speed. Because high-frequency electrical signals are prone to attenuation, transmission loss must be kept low. For this reason, resins used in semiconductor devices are required to have a low dielectric dissipation factor.

Furthermore, when forming a cured relief pattern, development is performed using a developer, and an alkaline aqueous developer or an organic solvent developer is generally used. Photosensitive resins for obtaining a cured relief pattern can be divided into positive-type resins, in which the photosensitive resin in the exposed areas dissolves in the developer and the photosensitive resin in the unexposed areas remains after exposure and development, and negative-type resins, in which the photosensitive resin in the unexposed areas dissolves in the developer and the photosensitive resin in the exposed areas remains. Negative-type resins have inferior resolution compared to positive-type resins, but are easy to form thicker films and have excellent reliability, and are used in the manufacture of semiconductor devices requiring such characteristics. However, negative-type photosensitive resins containing polyamic acid have the problem of low storage stability. On the other hand, negative-type photosensitive resins containing polyimide have the problem of long development times in organic solvent development.
Furthermore, when a thick film is formed using a negative photosensitive resin, it is desirable that the residual stress is low in order to reduce warpage of the semiconductor wafer.

Therefore, there is a demand for a photosensitive resin composition which produces a cured film having a low dielectric loss tangent, excellent storage stability, a short development time in organic solvent development even when it contains polyimide, and low residual stress.
However, the photosensitive resin compositions described in Patent Documents 1 to 4 do not satisfy all of these properties.

In view of the above circumstances, the object of the present invention is to provide a photosensitive resin composition that produces a cured film having a low dielectric tangent, excellent storage stability, a short development time in organic solvent development even when containing polyimide, and low residual stress; a resin film produced from the composition; a photosensitive resist film using the composition; a method for producing a substrate with a cured relief pattern; and a semiconductor device having a cured relief pattern.

As a result of extensive research to achieve the above-mentioned objectives, the inventors discovered that, in a photosensitive resin composition containing a polyimide and a solvent, when the polyimide has a divalent aromatic group having a photopolymerizable group and a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and no alicyclic structure, the resulting cured film has a low dielectric tangent, excellent storage stability, and even when containing polyimide, a photosensitive resin composition can be obtained that has a short development time in organic solvent development and low residual stress, leading to the completion of the present invention.

[1] A method for producing a polyimide composition comprising:
the polyimide has a divalent aromatic group having a photopolymerizable group and a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure;
Photosensitive resin composition.
[2] The polyimide is a reaction product of a diamine component and a tetracarboxylic acid derivative,
the diamine component contains an aromatic diamine compound having a photopolymerizable group and an aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure;
The photosensitive resin composition according to [1].
[3] The aromatic diamine compound having a photopolymerizable group is represented by the following formula (1-a):
The aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure is represented by the following formula (1-b):
The photosensitive resin composition according to [2].
[In formula (1-a), X represents a direct bond, an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond; Y represents an oxygen atom or an NH group; _R1 represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxyl group; and _R2 represents a hydrogen atom or a methyl group.]
[In formula (1-b), Z represents a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure.]
[4] The photosensitive resin composition according to [3], wherein X in the formula (1-a) represents an ester bond, and Y represents an oxygen atom.
[5] The photosensitive resin composition according to [3] or [4], wherein R ₁ in the formula (1-a) represents a 1,2-ethylene group.
[6] The photosensitive resin composition according to any one of [3] to [5], wherein the aliphatic diamine compound represented by the formula (1-b) contains two or more aliphatic diamine compounds having different structural formulas.
[7] The photosensitive resin composition according to any one of [2] to [6], wherein the tetracarboxylic acid derivative is a tetracarboxylic acid dianhydride.
[8] The photosensitive resin composition according to any one of [1] to [7], further comprising a photoradical polymerization initiator.
[9] The photosensitive resin composition according to any one of [1] to [8], further comprising a crosslinkable compound.
[10] The photosensitive resin composition according to any one of [1] to [9], which is used for forming an insulating film.
[11] The photosensitive resin composition according to any one of [1] to [10], which is a negative photosensitive resin composition.
[12] A resin film obtained by firing a coating film of the photosensitive resin composition according to any one of [1] to [11].
[13] The resin film according to [12], which is an insulating film.
[14] A photosensitive resist film comprising a base film, a photosensitive resin layer formed from the photosensitive resin composition according to any one of [1] to [11], and a cover film.
[15] (1) A step of applying the photosensitive resin composition according to any one of [1] to [11] onto a substrate to form a photosensitive resin layer on the substrate;
(2) exposing the photosensitive resin layer to light;
(3) developing the exposed photosensitive resin layer to form a relief pattern;
(4) heat-treating the relief pattern to form a hardened relief pattern;
A method for producing a substrate with a cured relief pattern, comprising:
[16] The method for producing a substrate having a cured relief pattern according to [15], wherein the developer used for the development is an organic solvent.
[17] A substrate having a cured relief pattern produced by the method according to [15] or [16].
[18] A semiconductor device comprising a semiconductor element and a cured film provided on the upper or lower part of the semiconductor element, wherein the cured film is a cured relief pattern formed from the photosensitive resin composition according to any one of [1] to [11].

The present invention provides a photosensitive resin composition that produces a cured film with a low dielectric tangent, excellent storage stability, a short development time in organic solvent development even when containing polyimide, and low residual stress; a resin film produced from the composition; a photosensitive resist film using the composition; a method for producing a substrate with a cured relief pattern; and a semiconductor device having a cured relief pattern.

(Photosensitive resin composition)
The photosensitive resin composition of the present invention contains at least a polyimide and a solvent, and may further contain other components as required.

<Polyimide>
The polyimide has a divalent aromatic group having a photopolymerizable group.
The polyimide has a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and no alicyclic structure.

The present inventors believe that the reason why the photosensitive resin composition of the present invention exhibits the effects of the present invention is as follows.
The polyimide has a divalent aromatic group having a photopolymerizable group, and thus the resin composition containing the polyimide is imparted with photosensitivity.
When the polyimide has a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms, the dielectric loss tangent of the cured film is reduced.
When the polyimide has a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms, the residual stress can be reduced.
When the polyimide has a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms, the developing time in organic solvent development can be shortened.
When the photosensitive resin composition contains a polyimide, the photosensitive resin composition has excellent storage stability.

The polyimide is, for example, an imidized product of polyamic acid.
The polyamic acid is, for example, a reaction product of a diamine component and a tetracarboxylic acid derivative.

The imidization rate of the polyimide does not need to be 100%. The imidization rate of the polyimide may be, for example, 90% or more, 95% or more, or 98% or more.

<<Divalent Aromatic Group Having a Photopolymerizable Group>>
Examples of the photopolymerizable group include a radically polymerizable group, a cationically polymerizable group, and an anionically polymerizable group. Of these, the radically polymerizable group is preferred.
Examples of the radically polymerizable group include an acryloyl group, a methacryloyl group, a propenyl ether group, a vinyl ether group, and a vinyl group.

Examples of the aromatic ring in the divalent aromatic group having a photopolymerizable group include a benzene ring, a naphthalene ring, and an anthracene ring.

A divalent aromatic group having a photopolymerizable group is, for example, a residue obtained by removing two amino groups from a diamine.

The divalent aromatic group having a photopolymerizable group is preferably a divalent organic group represented by the following formula (1-A).
[In formula (1-A), X represents a direct bond, an ether bond (—O—), an ester bond (—COO—), an amide bond (—NHCO—), a urethane bond (—NHCOO—), or a urea bond (—NHCONH—); Y represents an oxygen atom or an NH group; _R1 represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxyl group; and _R2 represents a hydrogen atom or a methyl group. * represents a bond.]

The two bonds in formula (1-A) are, for example, bonds bonded to a nitrogen atom.

In this specification, examples of alkylene groups having 2 to 6 carbon atoms that may be substituted with hydroxyl groups include 1,1-ethylene, 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,4-butylene, 1,2-butylene, 2,3-butylene, 1,2-pentylene, 2,4-pentylene, 1,2-hexylene, 1,2-cyclopropylene, 1,2-cyclobutylene, 1,3-cyclobutylene, 1,2-cyclopentylene, 1,2-cyclohexylene, and alkylene groups in which at least a portion of the hydrogen atoms have been substituted with hydroxyl groups (e.g., 2-hydroxy-1,3-propylene).

X preferably represents an ester bond (—COO—).
Preferably, Y represents an oxygen atom.
Preferably, _R1 represents a 1,2-ethylene group.

Examples of the divalent organic group represented by formula (1-A) include divalent organic groups represented by the following formulas:
In the formula, * represents a bond, and the two bonds are located, for example, at meta positions relative to the substituent having the photopolymerizable group.

<<Divalent Aliphatic Hydrocarbon Group Having 14 to 28 Carbon Atoms and Not Having an Alicyclic Structure>>
The divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The number of unsaturated groups in the unsaturated aliphatic hydrocarbon group is not particularly limited and may be one or two or more.
The alicyclic structure is also called an aliphatic hydrocarbon ring.

From the viewpoint of optimally achieving the effects of the present invention, the number of carbon atoms in the divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure is preferably 15 to 26, more preferably 16 to 24, even more preferably 17 to 23, and particularly preferably 18 to 22.

As the divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and no alicyclic structure, a divalent organic group represented by the following formula (1-B) is preferred, from the viewpoint of suitably achieving the effects of the present invention.
[In formula (1-B), Z represents a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure. * represents a bond.]

Z is, for example, an alkylene group or alkenylene group having 14 to 28 carbon atoms. The number of carbon-carbon double bonds in the alkenylene group may be one or two or more.
Z is, for example, linear.
Z may have a branched chain. In other words, Z may be branched. Examples of the branched chain include an alkyl group having 1 to 4 carbon atoms and an alkenyl group having 2 to 4 carbon atoms. The number of branched chains is not particularly limited, and may be one or two or more. The position of the branched chain in Z is not particularly limited.

Examples of branched alkyl groups having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl groups.
Examples of branched alkenyl groups having 2 to 4 carbon atoms include vinyl, 1-propenyl, allyl, 1-butenyl, 2-butenyl, and 3-butenyl groups.

Polyimides may contain two or more types of "divalent aliphatic hydrocarbon groups having 14 to 28 carbon atoms and no alicyclic structure" with different structural formulas.

<<Tetravalent organic group having three or more aromatic rings>>
The polyimide preferably has a tetravalent organic group having three or more aromatic rings, since this will result in a lower dielectric loss tangent in the resulting cured film.

A tetravalent organic group having three or more aromatic rings is, for example, a residue obtained by removing a carboxyl group, a carboxylic acid ester group, or a carboxylic acid dianhydride group from a tetracarboxylic acid derivative. A tetravalent organic group having three or more aromatic rings is, for example, a residue obtained by removing two acid anhydride groups from a tetracarboxylic acid dianhydride.

The number of aromatic rings in a tetravalent organic group having three or more aromatic rings is not particularly limited as long as it is three or more, but may be, for example, four or more. The upper limit of the number of aromatic rings is not particularly limited, but may be, for example, eight or less, or six or less.

Regarding the counting of aromatic rings in "three or more aromatic rings," polycyclic aromatic rings formed by the fusion of two or more aromatic rings, such as naphthalene rings and anthracene rings, are counted as one aromatic ring. Therefore, a naphthalene ring is counted as one aromatic ring. On the other hand, a biphenyl ring is not a fused ring, so it is counted as two aromatic rings. And a perylene ring is considered to be a structure formed by the bonding of two naphthalene rings, and is counted as two aromatic rings.
Examples of the aromatic ring include an aromatic hydrocarbon ring and an aromatic heterocyclic ring.

The tetravalent organic group having three or more aromatic rings is preferably a tetravalent organic group represented by the following formula (2-A).
[In formula (2-A), _X1 and _X2 each independently represent a direct bond, an ether bond (-O-), an ester bond (-COO-), an amide bond (-NHCO-), a urethane bond (-NHCOO-), a urea bond (-NHCONH-), a thioether bond (-S-) or a sulfonyl bond (-SO ₂ -).
R _a1 and R _a2 each independently represent an optionally substituted alkyl group having 1 to 6 carbon atoms.
_Z1 represents a divalent organic group represented by the following formula (3-a), (3-b), or (3-c).
n1 and n2 each independently represent an integer of 0 to 3.
When there are a plurality of R _{a1 's} , the plurality of R _{a1 's} may be the same or different, and when there are a plurality of _{R a2 's} , the plurality of R _{a2 's} may be the same or different.
* represents a bond.

Examples of the optionally substituted alkyl group having 1 to 6 carbon atoms for R _a1 and R _a2 in formula (2-A) include alkyl groups having 1 to 6 carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. In this specification, the alkyl group and alkylene group may be linear, branched, or cyclic, or may be a combination of two or more of these, unless otherwise specified with respect to their structure.
Examples of the substituent in the optionally substituted alkyl group having 1 to 6 carbon atoms include a halogen atom, a hydroxy group, a mercapto group, a carboxy group, a cyano group, a formyl group, a haloformyl group, a sulfo group, an amino group, a nitro group, a nitroso group, an oxo group, a thioxy group, and an alkoxy group having 1 to 6 carbon atoms.
The term "1 to 6 carbon atoms" in the "optionally substituted alkyl group having 1 to 6 carbon atoms" refers to the number of carbon atoms in the "alkyl group" excluding the substituents. The number of substituents is not particularly limited.

In formula (3-a), R _a3 represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and m ₁ represents an integer of 0 to 4. When m ₁ is 2 or more, R _a3 may be the same or different.
In formula (3-b), _Z2 represents a direct bond or a divalent organic group represented by the following formula (4-a) or (4-b), R _a4 and R _a5 each independently represent an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and _m2 and _m3 each independently represent an integer of 0 to 4. When _m2 is 2 or more, R _a4s may be the same or different. When _m3 is 2 or more, R _a5s may be the same or different.
In formula (3-c), R _a6 represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and _m4 represents an integer of 0 to 6. When _m4 is 2 or more, R _a6 may be the same or different.
* represents a bond.
In formula (4-a), R ₇ and R ₈ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom.
In formula (4-b), R ₉ and R ₁₀ each independently represent an optionally substituted alkylene group having 1 to 6 carbon atoms or an optionally substituted arylene group having 6 to 12 carbon atoms.
* represents a bond.

Examples of the alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom in _R7 and _R8 include an alkyl group having 1 to 6 carbon atoms and a halogenated alkyl group having 1 to 6 carbon atoms.
Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group.
Examples of the halogen atom in the halogenated alkyl group having 1 to 6 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
The halogenation in the halogenated alkyl group having 1 to 6 carbon atoms may be partial or complete.

Examples of the substituent in the optionally substituted alkylene group having 1 to 6 carbon atoms in _R9 and _R10 include a halogen atom, a hydroxy group, a mercapto group, a carboxy group, a cyano group, a formyl group, a haloformyl group, a sulfo group, an amino group, a nitro group, a nitroso group, an oxo group, a thioxy group, and an alkoxy group having 1 to 6 carbon atoms.
Examples of the alkylene group having 1 to 6 carbon atoms which may be substituted include an alkylene group having 1 to 6 carbon atoms and a halogenated alkylene group having 1 to 6 carbon atoms. Examples of the alkylene group having 1 to 6 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group.
The "carbon atom number of 1 to 6" in the "optionally substituted alkylene group having 1 to 6 carbon atoms" refers to the number of carbon atoms in the "alkylene group" excluding the substituent. The number of substituents is not particularly limited.

Examples of the substituent in the optionally substituted arylene group having 6 to 10 carbon atoms in _R9 and _R10 include a halogen atom, an optionally halogenated alkyl group having 1 to 6 carbon atoms, an optionally halogenated alkoxy group having 1 to 6 carbon atoms, etc. The halogenation may be partial or complete.
Examples of the arylene group include a phenylene group and a naphthylene group.
The term "6 to 10 carbon atoms" in the "optionally substituted arylene group having 6 to 10 carbon atoms" refers to the number of carbon atoms in the "arylene group" excluding the substituents. The number of substituents is not particularly limited.

Examples of the divalent organic group represented by formula (4-a) include divalent organic groups represented by the following formulas:
In the formula, * represents a bond.

Examples of the divalent organic group represented by formula (4-b) include divalent organic groups represented by the following formulas:
In the formula, R ₁₃ to R ₁₅ each independently represent a halogen atom, an alkyl group of 1 to 6 carbon atoms which may be substituted with a halogen atom, or an alkoxy group of 1 to 6 carbon atoms which may be substituted with a halogen atom. n13 represents an integer of 0 to 5. n14 and n15 each independently represent an integer of 0 to 4. When there is a plurality of _{R 13s} , the plurality of R _13s may be the same or different. When there is a plurality of R _14s , the plurality of R _14s may be the same or different. When there is a plurality of R _15s , the plurality of R _15s may be the same or different. * represents a bond.

Specific examples of the alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom in R ₁₃ to R ₁₅ include an alkyl group having 1 to 6 carbon atoms and a halogenated alkyl group having 1 to 6 carbon atoms.
Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group.
Examples of the halogen atom in the halogenated alkyl group having 1 to 6 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The halogenated alkyl group having 1 to 6 carbon atoms may be partially or completely halogenated.
Specific examples of the alkoxy group having 1 to 6 carbon atoms which may be substituted with a halogen atom for R ₁₃ to R ₁₅ include alkoxy groups obtained by converting alkyl groups having 1 to 6 carbon atoms which may be substituted with a halogen atom.

Examples of the tetravalent organic group having three or more aromatic rings include tetravalent organic groups represented by the following formula:
In the formula, * represents a bond.

<<Divalent Organic Group Having Three or More Aromatic Rings>>
In order to obtain a cured film having a lower dielectric loss tangent, the polyimide preferably has a divalent organic group having three or more aromatic rings. Here, the divalent organic group having three or more aromatic rings refers to an organic group different from the divalent aromatic group having a photopolymerizable group.
The divalent organic group having three or more aromatic rings is, for example, a residue obtained by removing two amino groups from a diamine.

The number of aromatic rings in a divalent organic group having three or more aromatic rings is not particularly limited as long as it is three or more, but may be, for example, four or more. The upper limit of the number of aromatic rings is not particularly limited, but may be, for example, eight or less, or six or less.

The divalent organic group having three or more aromatic rings is not particularly limited, but is preferably a divalent organic group represented by the following formula (13).
[In formula (13), X ₂₁ and X ₂₂ each independently represent a direct bond, an ether bond (—O—), an ester bond (—COO—), an amide bond (—NHCO—), a urethane bond (—NHCOO—), a urea bond (—NHCONH—), a thioether bond (—S—) or a sulfonyl bond (—SO ₂ —).
R ₂₁ and R ₂₂ each independently represent an alkyl group having 1 to 6 carbon atoms which may be substituted.
Y ₂₀ represents a divalent organic group represented by the above formula (3-a), (3-b) or (3-c).
n21 and n22 each independently represent an integer of 0 to 4.
When there are a plurality of R _{21 s} , the plurality of R _{21 s} may be the same or different, and when there are a plurality of _{R 22 s} , the plurality of R ₂₂ s may be the same or different.
* represents a bond.

Specific examples of the optionally substituted alkyl group having 1 to 6 carbon atoms for R ₂₁ and R ₂₂ include the optionally substituted alkyl groups having 1 to 6 carbon atoms exemplified in the description of R _a1 and R _a2 in formula (2-A).
The term "1 to 6 carbon atoms" in the "optionally substituted alkyl group having 1 to 6 carbon atoms" refers to the number of carbon atoms in the "alkyl group" excluding the substituents. The number of substituents is not particularly limited.

Examples of the divalent organic group having three or more aromatic rings include divalent organic groups represented by the following formula:
In the formula, * represents a bond.

<<Other organic groups>>
The polyimide may have other organic groups, such as divalent organic groups other than those mentioned above and tetravalent organic groups other than those mentioned above.

Examples of divalent organic groups other than those mentioned above include divalent organic groups represented by the following formulas: These divalent organic groups are, for example, residues obtained by removing two amino groups from a diamine.
In the formula, * represents a bond.

Examples of tetravalent organic groups other than those described above include tetravalent organic groups represented by the following formulas. These tetravalent organic groups are, for example, residues obtained by removing a carboxyl group, a carboxylic acid ester group, or a carboxylic acid dianhydride group from a tetracarboxylic acid derivative. These tetravalent organic groups are, for example, residues obtained by removing two acid anhydride groups from a tetracarboxylic acid dianhydride.
In the formula, * represents a bond.

<<Diamine component>>
The diamine component preferably contains an aromatic diamine compound having a photopolymerizable group.
The diamine component preferably contains an aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure.
The divalent aromatic group having a photopolymerizable group is derived from, for example, an aromatic diamine compound having a photopolymerizable group.
The divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure is derived from, for example, an aliphatic diamine compound having 14 to 28 carbon atoms and not having an alicyclic structure.

<<<Aromatic diamine compound having a photopolymerizable group>>>
In the aromatic diamine compound having a photopolymerizable group, the two amino groups may be bonded to one aromatic ring, or when the compound has two or more aromatic rings, they may be bonded to each of the two aromatic rings. Examples of the aromatic ring include an aromatic hydrocarbon ring and an aromatic heterocycle.
The aromatic diamine compound may have an aromatic ring to which no amino group is bonded.

As the aromatic diamine compound having a photopolymerizable group, a diamine compound represented by the following formula (1-a) is preferred from the viewpoint of suitably obtaining the effects of the present invention.
[In formula (1-a), X represents a direct bond, an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond; Y represents an oxygen atom or an NH group; _R1 represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxyl group; and _R2 represents a hydrogen atom or a methyl group.]

X preferably represents an ester bond (—COO—).
Preferably, Y represents an oxygen atom.
Preferably, _R1 represents a 1,2-ethylene group.

Examples of the diamine compound represented by formula (1-a) include the following diamine compounds.
In the formula, the two amino groups are located, for example, at the meta position relative to the substituent having the photopolymerizable group.

The ratio of the aromatic diamine compound having a photopolymerizable group to the total diamine components constituting the polyimide is not particularly limited, but from the viewpoint of obtaining sufficient photosensitivity, 10 mol% to 90 mol% is preferred, 15 mol% to 75 mol% is more preferred, and 20 mol% to 60 mol% is particularly preferred.

<<<<Aliphatic diamine compounds having 14 to 28 carbon atoms and not having an alicyclic structure>>>
The aliphatic hydrocarbon group in the aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The number of unsaturated groups in the unsaturated aliphatic hydrocarbon group is not particularly limited and may be one or two or more.

From the viewpoint of optimally achieving the effects of the present invention, the number of carbon atoms in the aliphatic diamine compound having 14 to 28 carbon atoms and not having an alicyclic structure is preferably 15 to 26, more preferably 16 to 24, even more preferably 17 to 23, and particularly preferably 18 to 22.

As the aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure, an aliphatic diamine compound represented by the following formula (1-b) is preferred from the viewpoint of suitably achieving the effects of the present invention.
[In formula (1-b), Z represents a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure.]

Z is, for example, an alkylene group or alkenylene group having 14 to 28 carbon atoms. The number of carbon-carbon double bonds in the alkenylene group may be one or two or more.
Z is, for example, linear.
Z may have a branched chain. In other words, Z may be branched. Examples of the branched chain include an alkyl group having 1 to 4 carbon atoms and an alkenyl group having 2 to 4 carbon atoms. The number of branched chains is not particularly limited, and may be one or two or more. The position of the branched chain in Z is not particularly limited.

Examples of branched alkyl groups having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl groups.
Examples of branched alkenyl groups having 2 to 4 carbon atoms include vinyl, 1-propenyl, allyl, 1-butenyl, 2-butenyl, and 3-butenyl groups.

Examples of the aliphatic diamine compound having 14 to 28 carbon atoms and not having an alicyclic structure include linear saturated diamines, linear unsaturated diamines, branched saturated diamines, and branched unsaturated diamines.
Examples of the linear saturated diamine include 1,14-tetradecanediamine, 1,16-hexadecanediamine, 1,18-octadecanediamine, 1,20-eicosadiamine, 1,22-docosadiamine, 1,24-tetracosadiamine, and 1,28-octacosadiamine.
Examples of linear unsaturated diamines include 1,14-tetradecanediamine-7-ene, 1,16-hexadecanediamine-6-ene, 1,16-hexadecanediamine-8-ene, 1,18-octadecanediamine-8-ene, 1,18-octadecanediamine-10-ene, 1,20-eicosadiamine-6-ene, 1,20-eicosadiamine-8-ene, and 1,20-eicosadiamine-10-ene. 1,20-eicosadiamine-8,12-diene, 1,20-eicosadiamine-10,14-diene, 1,22-docosadiamine-7,11,15-triene, 1,22-docosadiamine-8,12,16-triene, 1,24-tetracosadiamine-8,12,16-triene, and 1,24-tetracosadiamine-10,14,18-triene.
Examples of branched saturated diamines include 6,8-dimethyl-1,14-tetradecanediamine, 7-ethyl-1,14-tetradecanediamine, 7-propyl-1,14-tetradecanediamine, 7-ethyl-1,16-hexadecanediamine, 7-butyl-1,16-hexadecanediamine, 7-isopropyl-10-methyl-1,16-hexadecanediamine, 5-ethyl-1,18-octadecanediamine, and 6-ethyl-1,18-octadecanediamine. Examples of the diamine include 7-ethyl-1,18-octadecanediamine, 8-ethyl-1,18-octadecanediamine, 9-ethyl-1,18-octadecanediamine, 8-isopropyl-11-methyl-1,18-octadecanediamine, 8,13-diethyl-1,18-octadecanediamine, 8,13-dimethyl-1,20-eicosadiamine, 9,12-dimethyl-1,20-eicosadiamine, and 9,12-diethyl-1,20-eicosadiamine.
Examples of branched unsaturated diamines include 7-vinyl-1,14-tetradecanediamine, 7-vinyl-1,16-hexadecanediamine-8-ene, 7-isopropenyl-10-methyl-1,16-hexadecanediamine-9-ene, 8-vinyl-1,18-octadecanediamine-9-ene, 7,12-dimethyl-1,18-octadecanediamine-7,11-diene, 7,12-diethyl- Examples include 1,18-octadecanediamine-7,11-diene, 8-isopropenyl-11-methyl-1,18-octadecanediamine-10-ene, 8-ethyl-11-isopropenyl-1,18-octadecanediamine-10-ene, 8,13-dimethyl-1,20-eicosadiamine-8,12-diene, and 9,12-dimethyl-1,20-eicosadiamine-8,12-diene.

The aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure that constitutes the polyimide may contain two or more aliphatic diamine compounds with different structural formulas.

The aliphatic diamine compound having 14 to 28 carbon atoms and not having an alicyclic structure is, for example, a diamine compound described in WO 2021/049503.
The aliphatic diamine compound having 14 to 28 carbon atoms and not having an alicyclic structure can be obtained, for example, by the method for producing a diamine compound described in WO 2021/049503.
The aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure obtained by referring to these compounds may be a single composition or a mixture of two or more kinds.

The proportion of divalent aliphatic hydrocarbon groups having 14 to 28 carbon atoms and no alicyclic structure relative to the total diamine components constituting the polyimide is not particularly limited, but from the perspective of optimally achieving the effects of the present invention, it is preferably 5 mol% to 80 mol%, more preferably 10 mol% to 70 mol%, and particularly preferably 15 mol% to 60 mol%.

In the polyimide, the molar ratio (A:B) of the divalent aromatic group (A) having a photopolymerizable group to the divalent aliphatic hydrocarbon group (B) having 14 to 28 carbon atoms and not having an alicyclic structure is not particularly limited, but is preferably 5:1 to 0.3:1, more preferably 4:1 to 0.5:1, and particularly preferably 3:1 to 0.6:1.

The total molar ratio of the aromatic diamine compound having a photopolymerizable group and the divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure to all diamine components constituting the polyimide is not particularly limited, but from the viewpoint of optimally achieving the effects of the present invention, it is preferably 30 mol% or more, more preferably 40 mol% or more, and particularly preferably 50 mol% or more. There is no particular upper limit to the total molar ratio, but it may be 100 mol% or less, or may be 90 mol% or less.

<<<Aromatic diamine compounds having three or more aromatic rings>>>
In order to obtain a cured film having a lower dielectric tangent, the diamine component preferably contains an aromatic diamine compound having three or more aromatic rings. Note that the aromatic diamine compound having three or more aromatic rings here refers to a diamine compound different from the above-mentioned divalent aromatic diamine compound having a photopolymerizable group.

The number of aromatic rings in an aromatic diamine compound having three or more aromatic rings is not particularly limited as long as it is three or more, but may be, for example, four or more. The upper limit of the number of aromatic rings is not particularly limited, but may be, for example, eight or less, or six or less.

An example of the aromatic diamine compound having three or more aromatic rings is a diamine compound represented by the following formula (13-1).
[In formula (13-1), X ₂₁ and X ₂₂ each independently represent a direct bond, an ether bond (—O—), an ester bond (—COO—), an amide bond (—NHCO—), a urethane bond (—NHCOO—), a urea bond (—NHCONH—), a thioether bond (—S—) or a sulfonyl bond (—SO ₂ —).
R ₂₁ and R ₂₂ each independently represent an alkyl group having 1 to 6 carbon atoms which may be substituted.
Y ₂₀ represents a divalent organic group represented by the above formula (3-a), (3-b) or (3-c).
n21 and n22 each independently represent an integer of 0 to 4.
When there are multiple R _{21 s} , the multiple R _{21 s} may be the same or different. When there are multiple _{R 22 s} , the multiple R ₂₂ s may be the same or different.

The ratio of the aromatic diamine compound having three or more aromatic rings to the total diamine components constituting the polyimide is not particularly limited, but from the viewpoint of optimally achieving the effects of the invention, it is preferably 5 mol% to 60 mol%, more preferably 10 mol% to 55 mol%, and particularly preferably 15 mol% to 50 mol%.

<<Tetracarboxylic acid derivatives>>
The tetracarboxylic acid derivative preferably contains a tetracarboxylic acid derivative having three or more aromatic rings, since a lower dielectric loss tangent can be obtained in the resulting cured film.

The tetracarboxylic acid derivatives referred to in the "tetracarboxylic acid derivative" include, for example, tetracarboxylic acid dianhydrides, tetracarboxylic acid dihalides, tetracarboxylic acid dialkyl esters, and tetracarboxylic acid dialkyl ester dihalides, with tetracarboxylic acid dianhydrides being particularly preferred.

The number of aromatic rings in a tetracarboxylic acid derivative having three or more aromatic rings is not particularly limited as long as it is three or more, but may be, for example, four or more. The upper limit of the number of aromatic rings is not particularly limited, but may be, for example, eight or less, or six or less.

The tetracarboxylic acid derivative having three or more aromatic rings is preferably a tetracarboxylic acid derivative that provides the polyimide with the aforementioned tetravalent organic group having three or more aromatic rings, and is preferably a tetracarboxylic acid dianhydride that provides the aforementioned tetravalent organic group having three or more aromatic rings. Examples of such tetracarboxylic acid dianhydrides include the tetracarboxylic acid dianhydride represented by the following formula (2-A-1):
[In formula (2-A-1), _X1 and _X2 each independently represent a direct bond, an ether bond (—O—), an ester bond (—COO—), an amide bond (—NHCO—), a urethane bond (—NHCOO—), a urea bond (—NHCONH—), a thioether bond (—S—) or a sulfonyl bond (—SO ₂ —).
R _a1 and R _a2 each independently represent an optionally substituted alkyl group having 1 to 6 carbon atoms.
_Z1 represents a divalent organic group represented by the above formula (3-a), (3-b) or (3-c).
n1 and n2 each independently represent an integer of 0 to 3.
When there are multiple R _{a1 s} , the multiple R _{a1 s} may be the same or different. When there are multiple _{R a2 s} , the multiple R _{a2 s} may be the same or different.

The ratio of aromatic tetracarboxylic acid derivatives having three or more aromatic rings to all tetracarboxylic acid derivatives constituting the polyimide is not particularly limited, but from the viewpoint of optimally achieving the effects of the present invention, it is preferably 20 mol% to 100 mol%, and more preferably 50 mol% to 100 mol%.

The weight-average molecular weight of the polyimide is not particularly limited, but the weight-average molecular weight measured in polystyrene equivalent terms by gel permeation chromatography (hereinafter abbreviated as GPC in this specification) is preferably 5,000 to 100,0000, more preferably 7,000 to 50,000, even more preferably 10,000 to 50,000, and particularly preferably 10,000 to 40,000.

<<Polyimide manufacturing method>>
Polyimide can be obtained, for example, by imidizing polyamic acid.
The polyamic acid can be obtained, for example, by reacting a diamine component containing an aromatic diamine compound having a photopolymerizable group and an aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure with a tetracarboxylic acid derivative.

The method for producing polyimide or polyamic acid is not particularly limited, and examples include known methods for obtaining polyimide or polyamic acid by reacting a diamine component with a tetracarboxylic acid derivative. Polyimide and polyamic acid can be synthesized by known methods, such as those described in WO 2013/157586.

Polyamic acid is produced, for example, by reacting (condensation polymerization) diamine components, including an aromatic diamine compound having a photopolymerizable group and an aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure, with a tetracarboxylic acid derivative in a solvent.

Specific examples of the solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylpropionamide, N,N-dimethylisobutyric acid amide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidinone. When the polyamic acid has high solubility in the solvent, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or solvents represented by the following formulas [D-1] to [D-3] can be used.
(In formula [D-1], ^D1 represents an alkyl group having 1 to 3 carbon atoms, in formula [D-2], ^D2 represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-3], ^D3 represents an alkyl group having 1 to 4 carbon atoms.)

These solvents may be used alone or in combination. Furthermore, even if a solvent does not dissolve polyamic acid, it may be mixed with the above solvents to the extent that the polyamic acid does not precipitate.

When the diamine component and the tetracarboxylic acid derivative component are reacted in a solvent, the reaction can be carried out at any concentration, preferably 1% by mass to 50% by mass, more preferably 5% by mass to 30% by mass. The reaction can also be carried out at a high concentration in the initial stage, and then additional solvent can be added.
In the reaction, the ratio of the total number of moles of the diamine components to the total number of moles of the tetracarboxylic acid derivative components is preferably 0.8 to 1.2. As in a typical polycondensation reaction, the closer this molar ratio is to 1.0, the higher the molecular weight of the polyamic acid produced.

When the diamine component and the tetracarboxylic acid derivative component are reacted, a thermal polymerization inhibitor may be added to the reaction system to prevent polymerization of the photopolymerizable group.
Examples of the thermal polymerization inhibitor include hydroquinone, 4-methoxyphenol, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 2,6-di-tert-butyl-p-cresol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamine ammonium salt, and N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt.
The amount of the thermal polymerization inhibitor used is not particularly limited.

Polyimide can be obtained by dehydrating and cyclizing the polyamic acid obtained by the above reaction.
Methods for obtaining polyimide include thermal imidization, in which the polyamic acid solution obtained by the above reaction is heated as is, and chemical imidization, in which a catalyst is added to the polyamic acid solution. When thermal imidization is performed in a solution, the temperature is 100°C to 400°C, preferably 120°C to 250°C, and it is preferable to perform the imidization while removing water produced by the imidization reaction from the system.

The chemical imidization can be carried out by adding a basic catalyst and an acid anhydride to a solution of the polyamic acid obtained by the reaction and stirring at temperatures between -20°C and 250°C, preferably between 0°C and 180°C. The amount of the basic catalyst is 0.1 to 30 molar times, preferably 0.2 to 20 molar times, the amount of the amide acid groups. The amount of the acid anhydride is 1 to 50 molar times, preferably 1.5 to 30 molar times, the amount of the amide acid groups. Examples of basic catalysts include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Of these, triethylamine is preferred because it is less likely to produce the by-product polyisoimide. Examples of acid anhydrides include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Of these, acetic anhydride is preferred because it facilitates purification after the reaction. The imidization rate in chemical imidization (the ratio of repeating units that are ring-closed to all repeating units in the polyimide precursor, also known as the ring-closure rate) can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

To recover the imidized product produced from the imidization reaction solution, the reaction solution can be poured into a solvent to cause precipitation. Examples of solvents that can be used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated by pouring into the solvent can be recovered by filtration and then dried at room temperature or by heating under atmospheric or reduced pressure.

The polyimide may be end-capped. The end-capping method is not particularly limited, and conventional methods using monoamines or acid anhydrides can be used, for example.

<Solvent>
As the solvent contained in the photosensitive resin composition, an organic solvent is preferably used from the viewpoint of solubility in polyimide. Specific examples of the solvent include N,N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylpropionamide, N,N-dimethylisobutyric acid amide, dimethyl sulfoxide, diethylene glycol dimethyl ether, cyclopentanone, cyclohexanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, methyl 2-hydroxyisobutyrate, ethyl lactate, and solvents represented by the following formulas [D-1] to [D-3]. These may be used alone or in combination of two or more.
(In formula [D-1], ^D1 represents an alkyl group having 1 to 3 carbon atoms, in formula [D-2], ^D2 represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-3], ^D3 represents an alkyl group having 1 to 4 carbon atoms.)

The solvent can be used in an amount ranging from 30 to 1,500 parts by weight, preferably from 100 to 1,000 parts by weight, per 100 parts by weight of polyimide, depending on the desired coating thickness and viscosity of the photosensitive resin composition.

<Other ingredients>
In an embodiment, the photosensitive resin composition may further contain other components in addition to the polyimide and the solvent, such as a photoradical polymerization initiator (also referred to as a "photoradical initiator"), a crosslinking compound (also referred to as a "crosslinking agent"), a thermosetting agent, other resin components, a filler, a sensitizer, an adhesion promoter, a thermal polymerization inhibitor, an azole compound, a hindered phenol compound, etc.

<<Photoradical polymerization initiator>>
The photoradical polymerization initiator is not particularly limited as long as it is a compound that has absorption in the light source used for photocuring, and examples thereof include tert-butylperoxy-iso-butylate, 2,5-dimethyl-2,5-bis(benzoyldioxy)hexane, 1,4-bis[α-(tert-butyldioxy)-iso-propoxy]benzene, di-tert-butylperoxide, 2,5-dimethyl-2,5-bis(tert-butyldioxy)hexene hydroperoxide, α-(iso-propylphenyl)-iso-propyl hydroperoxide, tert-butyl hydroperoxide, 1,1-bis(tert-butyldioxy)-3,3,5-trimethylcyclohexane, butyl-4,4-bis(tert-butyldioxy)valerate, cyclohexane ... Organic peroxides such as chlorohexanone peroxide, 2,2',5,5'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-amylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-hexylperoxycarbonyl)benzophenone, 3,3'-bis(tert-butylperoxycarbonyl)-4,4'-dicarboxybenzophenone, tert-butyl peroxybenzoate, and di-tert-butyl diperoxyisophthalate; 9,10-anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, and octamethylanthraquinone, Quinones such as 1,2-benzanthraquinone; benzoin derivatives such as benzoin methyl, benzoin ethyl ether, α-methylbenzoin, and α-phenylbenzoin; 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-[4-{4-(2-hydroxy-2-methyl-propionyl)benzyl}-phenyl]-2-methyl-propan-1-one, phenylglyoxylic acid methyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, Examples of suitable oxime ester compounds include alkylphenone compounds such as pan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, and 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one; acylphosphine oxide compounds such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide; and oxime ester compounds such as 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(O-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone.

The photoradical polymerization initiator is commercially available, for example, IRGACURE [registered trademark] 651, 184, 2959, 127, 907, 369, 379EG, 819, 819DW, 1800, 1870, 784, OXE01, OXE02, OXE03, OXE04, 250, 1173, MBF, TPO, 4265, TPO (all manufactured by BASF), KAYACURE [registered trademark] DETX-S, MBP, DMBI, EPA, OA (all manufactured by Nippon Kayaku Co., Ltd.), VICURE-10, VICURE-55 (all manufactured by Stauffer Co. Ltd.), ESACURE Examples of suitable acrylic resins include KIP150, TZT, 1001, KTO46, KB1, KL200, KS300, EB3, Triazine-PMS, Triazine A, and Triazine B (all manufactured by Nippon SiberHegner Co., Ltd.), ADEKA OPTOMER N-1717, N-1414, N-1606, ADEKA ARCLES N-1919T, NCI-831E, NCI-930, and NCI-730 (all manufactured by ADEKA Corporation).
These photoradical polymerization initiators may be used alone or in combination of two or more.

The amount of photoradical polymerization initiator contained is not particularly limited, but is preferably 0.1 to 20 parts by mass per 100 parts by mass of polyimide, and more preferably 0.5 to 15 parts by mass from the perspective of photosensitivity characteristics. When the amount of photoradical polymerization initiator contained is 0.1 part by mass or more per 100 parts by mass of polyimide, the photosensitivity of the photosensitive resin composition is likely to be improved, while when the amount contained is 20 parts by mass or less, the thick-film curing properties of the photosensitive resin composition are likely to be improved.

<<Crosslinkable compound>>
In an embodiment, in order to improve the resolution of the relief pattern, a monomer (crosslinkable compound) having a photoradical polymerizable unsaturated bond may be optionally contained in the photosensitive resin composition.
Such a crosslinkable compound is preferably a (meth)acrylic compound that undergoes a radical polymerization reaction with a photoradical polymerization initiator, and includes, but is not limited to, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, ethylene glycol or polyethylene glycol mono- or di(meth)acrylate, propylene glycol or polypropylene glycol mono- or di(meth)acrylate, glycerol mono-, di- or tri(meth)acrylate, 1,4-butanediol, di(meth)acrylate of 1,6-hexanediol, di(meth)acrylate of 1,9-nonanediol, di(meth)acrylate of 1,10-decanediol, di(meth)acrylate of neopentyl glycol, cyclohexane di(meth)acrylate, di(meth)acrylate of cyclohexanedimethanol, di(meth)acrylate of tricyclodecanedimethanol, di(meth)acrylate of dioxane glycol, mono- or di(meth)acrylate of bisphenol A, bisphenol Di(meth)acrylate of bisphenol F, di(meth)acrylate of hydrogenated bisphenol A, benzene trimethacrylate, di(meth)acrylate of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene, di(meth)acrylate of tris(2-hydroxyethyl)isocyanurate, isobornyl (meth)acrylate, acrylamide and its derivatives, methacrylamide and its derivatives, trimethylolpropane tri(meth)acrylate, di- or tri(meth)acrylate of glycerol, pentaerythritol Examples of suitable compounds include di-, tri-, or tetra(meth)acrylates of teflon, as well as ethylene oxide or propylene oxide adducts of these compounds, 2-isocyanate ethyl (meth)acrylate or isocyanate-containing (meth)acrylates, and compounds obtained by adding a blocking agent such as methyl ethyl ketone oxime, ε-caprolactam, γ-caprolactam, 3,5-dimethylpyrazole, diethyl malonate, ethanol, isopropanol, n-butanol, or 1-methoxy-2-propanol to these compounds. These compounds may be used alone or in combination of two or more. In this specification, (meth)acrylate refers to acrylate and methacrylate.

The content of the crosslinkable compound is not particularly limited, but is preferably 1 to 100 parts by mass, and more preferably 1 to 50 parts by mass, per 100 parts by mass of polyimide.

<<Thermal curing agent>>
Examples of heat curing agents include hexamethoxymethylmelamine, tetramethoxymethylglycoluril, tetramethoxymethylbenzoguanamine, 1,3,4,6-tetrakis(methoxymethyl)glycoluril, 1,3,4,6-tetrakis(butoxymethyl)glycoluril, 1,3,4,6-tetrakis(hydroxymethyl)glycoluril, 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetrakis(butoxymethyl)urea, and 1,1,3,3-tetrakis(methoxymethyl)urea.
The content of the heat curing agent in the photosensitive resin composition is not particularly limited.

<<Filler>>
Examples of the filler include inorganic fillers, and specific examples include sols of silica, aluminum nitride, boron nitride, zirconia, alumina, and the like.
The content of the filler in the photosensitive resin composition is not particularly limited.

<<Other resin components>>
In an embodiment, the photosensitive resin composition may further contain a resin component other than polyimide, such as polyamic acid, polyamic acid ester, polyoxazole, polyoxazole precursor, phenolic resin, polyamide, epoxy resin, siloxane resin, or acrylic resin.
The content of these resin components is not particularly limited, but is preferably in the range of 0.01 to 20 parts by mass per 100 parts by mass of polyimide.

<<Sensitizer>>
In embodiments, the photosensitive resin composition may optionally contain a sensitizer to improve photosensitivity.
Examples of sensitizers include Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzal)cyclopentane, 2,6-bis(4'-diethylaminobenzal)cyclohexanone, 2,6-bis(4'-diethylaminobenzal)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, and p-dimethylaminocinnamylideneindano. p-dimethylaminobenzylidene indanone, 2-(p-dimethylaminophenylbiphenylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)isonaphthothiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3-acetyl [0039] Examples of the methylaminobenzoate include methylaminobenzoate, ...
These may be used alone or in combination.

The amount of sensitizer contained is not particularly limited, but it is preferably 0.1 to 25 parts by weight per 100 parts by weight of polyimide.

<<Adhesion aid>>
In an embodiment, an adhesion promoter may be optionally incorporated into the photosensitive resin composition to improve adhesion between the film formed using the photosensitive resin composition and the substrate.
Examples of the adhesion promoter include γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-(meth)acryloxypropyldimethoxymethylsilane, 3-(meth)acryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N-(3-diethoxymethylsilylpropyl)succinimide, N-[3-(triethoxysilyl)propyl]furan, Examples of the adhesive agent include silane coupling agents such as thalamic acid, benzophenone-3,3'-bis(N-[3-triethoxysilyl]propylamido)-4,4'-dicarboxylic acid, benzene-1,4-bis(N-[3-triethoxysilyl]propylamido)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propyl succinic anhydride and N-phenylaminopropyltrimethoxysilane, and aluminum-based adhesion promoters such as aluminum tris(ethylacetoacetate), aluminum tris(acetylacetonate) and ethylacetoacetate aluminum diisopropylate.

Of these adhesive aids, it is more preferable to use a silane coupling agent in terms of adhesive strength.

The amount of adhesive aid contained is not particularly limited, but is preferably in the range of 0.5 to 25 parts by weight per 100 parts by weight of polyimide.

<<Thermal polymerization inhibitor>>
In an embodiment, a thermal polymerization inhibitor may be optionally blended to improve the stability of the viscosity and photosensitivity of the photosensitive resin composition, particularly during storage in the form of a solution containing a solvent.
Examples of the thermal polymerization inhibitor include hydroquinone, 4-methoxyphenol, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 2,6-di-tert-butyl-p-cresol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamine ammonium salt, and N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt.

The amount of thermal polymerization inhibitor is not particularly limited, but is preferably in the range of 0.005 to 12 parts by weight per 100 parts by weight of polyimide.

<<Azole compounds>>
For example, when a substrate made of copper or a copper alloy is used, an azole compound can be optionally blended into the photosensitive resin composition to suppress discoloration of the substrate.
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 the like. 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, etc. Particularly preferred are 4-carboxy-1H-benzotriazole and 5-carboxy-1H-benzotriazole.
These azole compounds may be used alone or in combination of two or more.

The amount of the azole compound is not particularly limited, but is preferably 0.1 to 20 parts by mass per 100 parts by mass of polyimide, and more preferably 0.5 to 5 parts by mass from the viewpoint of photosensitivity characteristics. If the amount of the azole compound per 100 parts by mass of polyimide is 0.1 part by mass or more, discoloration of the copper or copper alloy surface is suppressed when the photosensitive resin composition is formed on copper or a copper alloy. On the other hand, if the amount is 20 parts by mass or less, excellent photosensitivity is achieved, which is preferable.

<<Hindered phenol compounds>>
In embodiments, a hindered phenol compound may optionally be incorporated into the photosensitive resin composition to inhibit discoloration on copper.
Examples of the hindered phenol compound include 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butyl-hydroquinone, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 4,4'-methylenebis(2,6-di-t-butylphenol), 4,4'-thio-bis(3-methyl-6-t-butylphenol), 4,4'-butylamine, ethylene-bis(3-methyl-6-t-butylphenol), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydroxyphenyl)propionate rosinamamide), 2,2'-methylene-bis(4-methyl-6-t-butylphenol), 2,2'-methylene-bis(4-ethyl-6-t-butylphenol), pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], tris-(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1 ,3,5-tris(3-hydroxy-2,6-dimethyl-4-isopropylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-s-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione 1,3,5-tris[4-(1-ethylpropyl)-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-triethylmethyl-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-phenylbenzyl)-1,3,5-triazine-2,4,6- (1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5,6-trimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl-3-hydroxy-2-methylbenzyl)-1, 3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5,6-diethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy- 2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, and the like, but are not limited thereto.
Among these, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione is particularly preferred.

The content of the hindered phenol compound is not particularly limited, but is preferably 0.1 to 20 parts by weight per 100 parts by weight of polyimide, and more preferably 0.5 to 10 parts by weight from the viewpoint of photosensitivity characteristics. If the content of the hindered phenol compound per 100 parts by weight of polyimide is 0.1 part by weight or more, when the photosensitive resin composition is formed on copper or a copper alloy, for example, discoloration and corrosion of the copper or copper alloy are prevented. On the other hand, if the content is 20 parts by weight or less, excellent photosensitivity is achieved, which is preferred.

The photosensitive resin composition can be suitably used as a negative-tone photosensitive resin composition for producing the cured relief pattern described below.

(Resin film)
The resin film of the present invention is a fired product of a coating film of the photosensitive resin composition of the present invention.
As the application method, a method conventionally used for applying a photosensitive resin composition, such as a method of applying using a spin coater, a bar coater, a blade coater, a curtain coater, a screen printing machine, or the like, or a method of spray application using a spray coater, can be used.
The firing method for obtaining the fired product can be selected from various methods, such as using a hot plate, an oven, or a temperature-programmable heating oven. The firing can be carried out, for example, at 130°C to 250°C for 30 minutes to 5 hours. The atmospheric gas during heat curing may be air, or an inert gas such as nitrogen or argon.
The thickness of the resin film is not particularly limited, but is preferably 1 μm to 100 μm, and more preferably 2 μm to 50 μm.
The resin film is, for example, an insulating film.

(Photosensitive resist film)
The photosensitive resin composition of the present invention can be used for a photosensitive resist film (so-called dry film resist).
The photosensitive resist film has a base film, a photosensitive resin layer (photosensitive resin film) formed from the photosensitive resin composition of the present invention, and a cover film.
Usually, a photosensitive resin layer and a cover film are laminated in this order on a substrate film.

The photosensitive resist film can be produced, for example, by applying a photosensitive resin composition onto a substrate film, drying it to form a photosensitive resin layer, and then laminating a cover film on the photosensitive resin layer.
As the application method, a method conventionally used for applying a photosensitive resin composition, such as a method of applying using a spin coater, a bar coater, a blade coater, a curtain coater, a screen printing machine, or the like, or a method of spray application using a spray coater, can be used.
The drying method may be, for example, at 20° C. to 200° C. for 1 minute to 1 hour.
The thickness of the resulting photosensitive resin layer is not particularly limited, but is preferably 1 μm to 100 μm, and more preferably 2 μm to 50 μm.

The substrate film may be a known film, such as a thermoplastic resin film. Examples of the thermoplastic resin include polyesters such as polyethylene terephthalate. The thickness of the substrate film is preferably 2 μm to 150 μm.
The cover film may be a known film, such as a polyethylene film or a polypropylene film. The cover film preferably has a lower adhesive strength with the photosensitive resin layer than the base film. The thickness of the cover film is preferably 2 μm to 150 μm, more preferably 2 μm to 100 μm, and particularly preferably 5 μm to 50 μm.
The base film and the cover film may be made of the same film material, or different films may be used.

(Method for producing a substrate having a cured relief pattern)
The method for producing a substrate having a cured relief pattern of the present invention comprises the steps of:
(1) a step of applying the photosensitive resin composition according to the present invention onto a substrate to form a photosensitive resin layer (photosensitive resin film) on the substrate;
(2) exposing the photosensitive resin layer to light;
(3) developing the exposed photosensitive resin layer to form a relief pattern;
(4) heat-treating the relief pattern to form a hardened relief pattern.

Each process is explained below.

(1) Step of applying the photosensitive resin composition of the present invention onto a substrate to form a photosensitive resin layer on the substrate In this step, the photosensitive resin composition of the present invention is applied onto a substrate, and then dried as necessary to form a photosensitive resin layer. As the application method, a method conventionally used for applying a photosensitive resin composition can be used, such as a method of applying using a spin coater, bar coater, blade coater, curtain coater, screen printing machine, etc., or a method of spray application using a spray coater, etc.

If necessary, the coating film made from the photosensitive resin composition can be dried. Examples of drying methods include air drying, heat drying in an oven or on a hot plate, and vacuum drying. Specifically, when air drying or heat drying is used, drying can be carried out at 20°C to 200°C for 1 minute to 1 hour. This allows a photosensitive resin layer to be formed on the substrate.

(2) Step of exposing photosensitive resin layer In this step, the photosensitive resin layer formed in step (1) above is exposed to an ultraviolet light source or the like using an exposure device such as a contact aligner, a mirror projection, or a stepper, either directly or through a photomask or reticle having a pattern.
Examples of light sources used for exposure include g-line, h-line, i-line, ghi-line broadband, and KrF excimer laser. The exposure dose is preferably 25 mJ/cm ² to 2000 mJ/cm ² .

After this, for purposes such as improving photosensitivity, post-exposure baking (PEB) and/or pre-development baking may be performed as needed using any combination of temperature and time. The baking conditions preferably range from 50°C to 200°C in temperature and from 10 to 600 seconds in time, but are not limited to these ranges as long as they do not impair the properties of the photosensitive resin composition.

(3) Step of Developing the Exposed Photosensitive Resin Layer to Form a Relief Pattern In this step, the unexposed portions of the exposed photosensitive resin layer are developed and removed. The development method for developing the exposed (irradiated) photosensitive resin layer can be any method selected from conventionally known photoresist development methods, such as the rotary spray method, the paddle method, and the immersion method accompanied by ultrasonic treatment. After development, rinsing may be performed to remove the developer. Furthermore, post-development baking may be performed at any temperature and time combination, as necessary, for the purpose of adjusting the shape of the relief pattern, etc.
The developer used for development is preferably an organic solvent, such as N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, etc. Two or more types of each solvent can also be used, for example, in combination.
The rinse solution used for rinsing is preferably an organic solvent that is miscible with the developer and has low solubility in the photosensitive resin composition. Examples of preferred rinse solutions include methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, toluene, and xylene. Two or more of each solvent, for example, a combination of several types, can also be used.

(4) Step of Heating the Relief Pattern to Form a Hardened Relief Pattern In this step, the relief pattern obtained by the development described above is heated to convert it into a hardened relief pattern. Various methods can be selected for heat curing, such as using a hot plate, an oven, or a temperature-programmable heating oven. Heating can be performed, for example, at 130°C to 250°C for 30 minutes to 5 hours. The atmospheric gas used during heat curing may be air, or an inert gas such as nitrogen or argon.

The thickness of the cured relief pattern is not particularly limited, but is preferably 1 μm to 100 μm, and more preferably 2 μm to 50 μm.

(Semiconductor device)
In an embodiment, a semiconductor device is provided that includes a semiconductor element and a cured film provided on or below the semiconductor element. The cured film is a cured relief pattern formed from the photosensitive resin composition of the present invention. The cured relief pattern can be obtained, for example, by steps (1) to (4) in the method for producing a substrate with a cured relief pattern described above.
The present invention can also be applied to a method for manufacturing a semiconductor device that uses a semiconductor element as a substrate and includes the above-mentioned method for manufacturing a substrate having a cured relief pattern as part of its steps. The semiconductor device of the present invention can be manufactured by forming a cured relief pattern as a surface protective film, an interlayer insulating film, an insulating film for rewiring, a protective film for a flip-chip device, or a protective film for a semiconductor device having a bump structure, and combining the method with a known method for manufacturing a semiconductor device.

(Display device)
In an embodiment, a display device is provided that includes a display element and a cured film disposed on the display element, the cured film having the above-described cured relief pattern. The cured relief pattern may be laminated in direct contact with the display element, or may be laminated via another layer. Examples of the cured film include surface protection films, insulating films, and planarizing films for TFT (Thin Film Transistor) liquid crystal display elements and color filter elements, protrusions for MVA (Multi-Domain Vertical Alignment) liquid crystal display devices, and partition walls for cathodes in organic EL (Electro-Luminescence) elements.

In addition to its application to semiconductor devices such as those described above, the photosensitive resin composition of the present invention is also useful for applications such as interlayer insulating films in multilayer circuits, cover coats for flexible copper-clad boards, solder resist films, and liquid crystal alignment films.

The following examples will explain the present invention in more detail, but the present invention is not limited to these.

The compounds shown in the following synthesis examples and comparative synthesis examples are as follows.
BEM-S: 2-(methacryloyloxy)ethyl 3,5-diaminobenzoate (manufactured by Mitsubishi Chemical Industries, Ltd.)

HFBAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane

A mixture of aliphatic diamine compounds having 14 to 28 carbon atoms and no alicyclic structure (hereinafter referred to as "mixture of aliphatic diamine compounds"):
The mixture of aliphatic diamine compounds is a mixture of the following (1) to (3):
(1) A saturated aliphatic diamine compound having 20 carbon atoms and no alicyclic structure. (2) A saturated aliphatic diamine compound having 20 carbon atoms and no alicyclic structure. (3) A saturated aliphatic diamine compound having 16 carbon atoms and no alicyclic structure. The mixing ratio of (1):(2):(3) (mass ratio) is 78:19:3. The main component (1) is 1,18-octadecanediamine having an ethyl group as a branched chain. (2) is a positional isomer of (1). Note that the amino group in each of (1) to (3) is _-NH2 .

BPADA: 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride

TMPBP-TME: 2,2',3,3',5,5'-hexamethyl-[1,1'-biphenyl]-4,4'-diylbis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate) (manufactured by Honshu Chemical Industry Co., Ltd.)

The weight average molecular weights (Mw) shown in the following synthesis examples are the results of measurements by gel permeation chromatography (hereinafter abbreviated as GPC in this specification). For the measurements, a GPC device (HLC-8320GPC (manufactured by Tosoh Corporation)) was used, and the measurement conditions were as follows:
Column: Shodex (registered trademark) KD-805/Shodex (registered trademark) KD-803 (manufactured by Showa Denko K.K.)
Column temperature: 50°C
Flow rate: 1 mL/min Eluent: N,N-dimethylformamide (DMF), lithium bromide monohydrate (30 mM)/phosphoric acid (30 mM)/tetrahydrofuran (1%)
・Standard sample: polyethylene oxide

The chemical imidization rates shown in the following synthesis examples are the results of measurements using a nuclear magnetic resonance spectrometer (hereinafter abbreviated as NMR) using an NMR spectrometer (JNM-ECA500) (manufactured by JEOL Ltd.) under the following measurement conditions:
Measurement temperature: room temperature Measurement solvent: deuterated tetrahydrofuran (THF-d8)
The chemical imidization rate was calculated by the following formula using a proton derived from a structure that does not change before and after imidization as a reference proton, the peak integrated value of this proton, and the peak integrated value of a proton derived from an NH group of an amic acid that appears in the vicinity of 9.5 ppm to 11.0 ppm.
Chemical imidization rate (%) = (1 - α x/y) x 100
In the above formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated value of the peak of the reference proton, and α is the ratio of the number of the reference protons to one NH group proton of the amic acid in the case of polyamic acid (imidization rate 0%).

Synthesis Example 1: Synthesis of Polyimide (P-1) 5.27 g (19.95 mmol) of BEM-S, 12.16 g (37.05 mmol) of a mixture of aliphatic diamine compounds (amine value: 341.7 mg KOH/g), and 168.66 g of N-ethyl-2-pyrrolidone were added to a four-neck flask and dissolved by stirring at room temperature under air. Furthermore, 14.54 g (27.93 mmol) of BPADA, 17.63 g (28.50 mmol) of TMPBP-TME, and 112.44 g of N-ethyl-2-pyrrolidone were added to the flask and stirred at 50°C for 20 hours to obtain a polyamic acid solution. Next, 164.50 g of N-ethyl-2-pyrrolidone, 17.37 g of acetic anhydride, and 2.87 g of triethylamine were added to the flask and chemical imidization was carried out by stirring at 60°C for 3 hours. This reaction solution was added dropwise to methanol, and the resulting precipitate was filtered and then dried under reduced pressure at 60° C. to obtain a polyimide powder. The weight average molecular weight (Mw) measured by GPC was 17,364, and the chemical imidization rate measured by NMR (THF-d8) was 99%.

Synthesis Example 2 Synthesis of Polyimide (P-2) 4.62 g (17.50 mmol) of BEM-S, 5.18 g (10.00 mmol) of HFBAPP, 7.39 g (22.50 mmol) of a mixture of aliphatic diamine compounds (amine value: 341.7 mg KOH/g), and 154.41 g of N-ethyl-2-pyrrolidone were added to a four-neck flask and dissolved by stirring at room temperature under air. Furthermore, 12.75 g (24.50 mmol) of BPADA, 15.46 g (25.00 mmol) of TMPBP-TME, and 102.94 g of N-ethyl-2-pyrrolidone were added to the flask and stirred at 50° C. for 16.5 hours to obtain a polyamic acid solution. Next, 150.50 g of N-ethyl-2-pyrrolidone, 15.23 g of acetic anhydride, and 2.51 g of triethylamine were added to the flask and stirred at 60°C for 3 hours to carry out chemical imidization. This reaction solution was added dropwise to methanol, and the resulting precipitate was filtered and then dried under reduced pressure at 60°C to obtain polyimide powder. The weight average molecular weight (Mw) measured by GPC was 22,041, and the chemical imidization rate measured by NMR (THF-d8) was 98%.

Synthesis Example 3 Synthesis of Polyimide (P-3) 4.53 g (17.15 mmol) of BEM-S, 8.89 g (17.15 mmol) of HFBAPP, 4.83 g (14.70 mmol) of a mixture of aliphatic diamine compounds (amine value: 341.7 mg KOH/g), and 156.07 g of N-ethyl-2-pyrrolidone were added to a four-neck flask and dissolved by stirring at room temperature under air. Furthermore, 12.50 g (24.01 mmol) of BPADA, 15.16 g (24.50 mmol) of TMPBP-TME, and 104.05 g of N-ethyl-2-pyrrolidone were added to the flask and stirred at 50° C. for 16.5 hours to obtain a polyamic acid solution. Next, 152.25 g of N-ethyl-2-pyrrolidone, 14.93 g of acetic anhydride, and 2.47 g of triethylamine were added to the flask and stirred at 60°C for 3 hours to carry out chemical imidization. This reaction solution was added dropwise to methanol, and the resulting precipitate was filtered and then dried under reduced pressure at 60°C to obtain polyimide powder. The weight average molecular weight (Mw) measured by GPC was 27,705, and the chemical imidization rate measured by NMR (THF-d8) was 98%.

Comparative Synthesis Example 1 Synthesis of Polyimide (P-4) 2.81 g (10.62 mmol) of BEM-S, 10.23 g (19.72 mmol) of HFBAPP, and 96.15 g of N-ethyl-2-pyrrolidone were added to a four-neck flask and dissolved by stirring at room temperature under air. Furthermore, 7.58 g (14.57 mmol) of BPADA, 9.39 g (15.17 mmol) of TMPBP-TME, and 73.85 g of N-ethyl-2-pyrrolidone were added to the flask and stirred at room temperature for 39 hours to obtain a polyamic acid solution. Next, 100.00 g of N-ethyl-2-pyrrolidone, 9.29 g of acetic anhydride, and 1.54 g of triethylamine were added to the flask and chemical imidization was carried out by stirring at 60°C for 3 hours. The reaction solution was diluted with 128.57 g of N-ethyl-2-pyrrolidone, and the diluted solution was added dropwise to methanol. The resulting precipitate was washed with methanol and then dried under reduced pressure at 60°C to obtain polyimide powder. The weight-average molecular weight (Mw) measured by GPC was 44,173, and the chemical imidization rate measured by NMR (THF-d8) was 99%.

Comparative Synthesis Example 2 Synthesis of Polyamic Acid (P-5) Polymerization was carried out in the same manner as in Synthesis Example 3 to obtain a polyamic acid solution.

The compounds shown in the examples and comparative examples are as follows.
NK Ester A-DOD-N: 1,10-decanediol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
IRGACURE [registered trademark] OXE01: 1,2-octanedione, 1-[4-(phenylthio)phenyl-, 2-(O-benzoyloxime)] (manufactured by BASF Japan Ltd.)
CaA-BTZ: 5-carboxybenzotriazole (Sigma-Aldrich Japan G.K.)
KBM-5103: 3-acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)

Example 1
A negative photosensitive resin composition was prepared by mixing and dissolving 6.00 g of the polyimide (P-1) obtained in Synthesis Example 1, 0.60 g of NK ester A-DOD-N as a crosslinking agent, 0.12 g of IRGACURE (registered trademark) OXE01 as a photoradical initiator, 0.18 g of CaA-BTZ, 0.12 g of KBM-5103, 4.48 g of N-ethyl-2-pyrrolidone, and 10.44 g of cyclopentanone, and then filtering the mixture using a polypropylene filter having a pore size of 5 μm.

Example 2
A negative photosensitive resin composition was prepared by mixing and dissolving 10.00 g of the polyimide (P-2) obtained in Synthesis Example 2, 1.50 g of NK Ester A-DOD-N as a crosslinking agent, 0.40 g of IRGACURE (registered trademark) OXE01 as a photoradical initiator, 0.30 g of CaA-BTZ, 0.20 g of KBM-5103, 9.57 g of N-ethyl-2-pyrrolidone, 12.75 g of γ-butyrolactone, and 9.57 g of cyclopentanone, and then filtering the mixture using a polypropylene filter having a pore size of 5 μm.

Example 3
31.35 g of the negative photosensitive resin composition obtained in Example 2 was diluted by mixing with 0.35 g of N-ethyl-2-pyrrolidone, 0.46 g of γ-butyrolactone, and 0.35 g of cyclopentanone.

Example 4
A negative photosensitive resin composition was prepared by mixing and dissolving 10.00 g of the polyimide (P-3) obtained in Synthesis Example 3, 1.50 g of NK Ester A-DOD-N as a crosslinking agent, 0.40 g of IRGACURE [registered trademark] OXE01 as a photoradical initiator, 0.30 g of CaA-BTZ, 0.20 g of KBM-5103, 10.06 g of N-ethyl-2-pyrrolidone, 13.41 g of γ-butyrolactone, and 10.06 g of cyclopentanone, and then filtering the mixture using a polypropylene filter having a pore size of 5 μm.

Example 5
33.52 g of the negative photosensitive resin composition obtained in Example 4 was diluted by mixing with 1.26 g of N-ethyl-2-pyrrolidone, 1.68 g of γ-butyrolactone, and 1.26 g of cyclopentanone.

<Comparative Example 1>
A negative photosensitive resin composition was prepared by mixing and dissolving 10.00 g of the polyimide (P-4) obtained in Comparative Synthesis Example 1, 1.50 g of NK Ester A-DOD-N as a crosslinking agent, 0.40 g of IRGACURE [registered trademark] OXE01 as a photoradical initiator, 0.30 g of CaA-BTZ, 0.20 g of KBM-5103, 12.45 g of N-ethyl-2-pyrrolidone, 16.61 g of γ-butyrolactone, and 12.45 g of cyclopentanone, and then filtering the mixture using a polypropylene filter having a pore size of 5 μm.

<Comparative Example 2>
32.89 g of the negative photosensitive resin composition obtained in Comparative Example 1 was diluted by mixing with 4.32 g of N-ethyl-2-pyrrolidone, 5.76 g of γ-butyrolactone, and 4.32 g of cyclopentanone.

<Comparative Example 3>
0.225 g of NK ester A-DOD-N as a crosslinking agent, 0.060 g of IRGACURE® OXE01, 0.045 g of CaA-BTZ, and 0.030 g of KBM-5103 as photoradical initiators were mixed and dissolved in 10.00 g of an N-ethyl-2-pyrrolidone solution (solid content concentration: 15% by mass) containing the polyamic acid (P-5) obtained in Comparative Synthesis Example 2, and the mixture was filtered using a polypropylene filter with a pore size of 5 μm to prepare a negative photosensitive resin composition.

[Electrical property evaluation]
The negative photosensitive resin compositions prepared in Examples 1, 2, 4, and Comparative Example 1 were spin-coated onto a 4-inch silicon wafer coated with 20 μm-thick aluminum foil and baked on a hot plate at 115°C for 270 seconds to form a photosensitive resin film of approximately 25 μm on the aluminum foil. The resulting photosensitive resin film was exposed to light at 500 mJ/ ^cm² on the entire surface of the wafer using an i-line aligner (PLA-501, manufactured by Canon Inc.), and then baked in a high-temperature clean oven (CLH-21CD(V)-S, manufactured by Koyo Thermo Systems Co., Ltd.) at 230°C for 2 hours in a nitrogen atmosphere. The baked aluminum foil was then immersed in 6N hydrochloric acid to dissolve the aluminum foil, yielding a film. The dielectric loss tangent of the resulting film at 60 GHz was measured using a split cylinder resonator. The dielectric loss tangent measurement conditions were as follows:
Measurement method: Split cylinder resonator Vector network analyzer: FieldFox N9926A (Keysight Technologies, Inc.)
・Resonator: CR-760 (manufactured by EM Lab Co., Ltd.)
・Measurement frequency: Approximately 60GHz
The measurement results of the dielectric loss tangent of the film at 60 GHz are shown in Table 1.

From the results in Table 1, the films obtained from the negative photosensitive resin compositions of Examples 1, 2, and 4 exhibited lower dielectric loss tangents at 60 GHz than the film obtained from the negative photosensitive resin composition of Comparative Example 1.

[Photosensitivity Evaluation]
The negative photosensitive resin compositions prepared in Examples 3, 5, and Comparative Example 2 were applied to 8-inch silicon wafers using a spin coater (CLEAN TRACK ACT-8, manufactured by Tokyo Electron Limited), and then baked at 115°C for 270 seconds to form photosensitive resin films with a thickness of approximately 6.5 μm on the wafers. A 7 mm square exposure pattern (exposure dose: 300 mJ/cm ² ) was created on the resulting photosensitive resin film using an i-line stepper (NSR-2205i12D, manufactured by Nikon Corporation). After exposure, the wafers were spray-developed using an automatic developing apparatus (AD-1200, manufactured by Mikasa Co., Ltd.) using cyclopentanone as the developer, followed by spray rinsing with propylene glycol monomethyl ether acetate (PGMEA) as the rinse solution. The development time with cyclopentanone was the time required for the unexposed area (0 mJ/cm ² ) to be completely developed, and the rinsing time with PGMEA was 10 seconds. The film thickness immediately after film formation and the film thickness after development in the unexposed and exposed areas (300 mJ/cm ² ) were measured using an interference film thickness meter (Lambda Ace VM-2110, manufactured by SCREEN Corporation), and the percentage of the film thickness remaining without development in the exposed area (residual film ratio (%)) was calculated using the following formula.
Residual film rate (%) = [(film thickness of unexposed portion) or (film thickness of exposed portion)] / (film thickness immediately after film formation) × 100
In other words, if the remaining film ratio is 80%, it means that 80% of the film thickness immediately after the film formation remains without being developed. The measurement results of the development time and the remaining film ratio after development are shown in Table 2.

From the results in Table 2, for the negative-tone photosensitive resin compositions of Examples 3, 5, and Comparative Example 2, after development, the unexposed areas of the photosensitive resin film were completely developed, while the exposed areas of the photosensitive resin film were hardly developed at all. Furthermore, the photosensitive resin film obtained from the negative-tone photosensitive resin composition of Comparative Example 2 required a longer development time with cyclopentanone than the photosensitive resin films obtained from the negative-tone photosensitive resin compositions of Examples 3 and 5. In other words, the photosensitive resin films obtained from the negative-tone photosensitive resin compositions of Examples 3 and 5 have high solubility in developer, which is effective in shortening the development time involved in the development process and reducing the amount of developer used.

[Residual stress evaluation]
The negative photosensitive resin compositions prepared in Examples 3, 5, and Comparative Example 2 were applied to new 8-inch silicon wafers with a thickness of 724 μm using a spin coater (CLEAN TRACK ACT-8, manufactured by Tokyo Electron Limited), and then baked at 115° C. for 270 seconds to form photosensitive resin films with a thickness of approximately 6.5 μm on the wafers.
Next, the entire surface was exposed to 500 mJ/ ^cm² using an i-line stepper (NSR-2205i12D, manufactured by Nikon Corporation). The film was then baked in a nitrogen atmosphere at 230°C for 2 hours using a high-temperature clean oven (CLH-21CD(V)-S, manufactured by Koyo Thermo Systems Co., Ltd.) to obtain a cured polyimide film. The residual stress of the resulting polyimide film was measured at room temperature using a thin film stress measurement system (FLX-3300-T, manufactured by KLA-Tencor Corporation).
The results of measuring the residual stress are shown in Table 3. Measurement values of 25 MPa or less were rated as "good," and values of 30 MPa or more were rated as "poor."

The results in Table 3 show that the polyimide cured films obtained from the negative-tone photosensitive resin compositions of Examples 3 and 5 have lower residual stress than the polyimide cured film obtained from the negative-tone photosensitive resin composition of Comparative Example 2, making the silicon wafer less likely to warp and less likely to cause problems during transportation or wafer fixation.

[Storage stability test]
The viscosity of the negative photosensitive resin compositions prepared in Example 3, Example 5, Comparative Example 2, and Comparative Example 3 was measured using an electromagnetic rotary EMS viscometer immediately after preparation. After storing the compositions at room temperature for three weeks, the viscosity was measured again using the same method. The degree of viscosity change over time (viscosity change rate (%)) was calculated using the following formula:
Viscosity change rate (%) = [1 - (viscosity after storage at room temperature for 3 weeks) / (viscosity immediately after preparation)] x 100
The viscosity measurement conditions are as follows.
・Electromagnetic rotational EMS viscometer: EMS-1000 (Kyoto Electronics Manufacturing Co., Ltd.)
・Measurement temperature: 25℃
・Spherical probe: 4.7 mm aluminum ・Rotation speed: 1000 rpm
The results of the storage stability test are shown in Table 4. The greater the viscosity change, the worse the storage stability of the negative-type photosensitive resin composition. An absolute value of the viscosity change rate of less than 3% was rated as "good," 3% to 10% as "slightly poor," and more than 10% as "poor."

From the results in Table 4, it can be said that the negative-type photosensitive resin compositions of Examples 3 and 5 and Comparative Example 2 have smaller viscosity changes and higher storage stability than the negative-type photosensitive resin composition of Comparative Example 3.

That is, the negative-type photosensitive resin compositions of Examples 1 to 5 not only enable the production of relief patterns in a short development time, but also have excellent storage stability, a low dielectric loss tangent, and small residual stress, and therefore can be suitably used for the production of electronic materials that require excellent electrical properties.

Claims (19)

a polyimide and a solvent,
the polyimide has a divalent aromatic group having a photopolymerizable group and a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure;
Photosensitive resin composition. The divalent aromatic group having a photopolymerizable group is a divalent organic group represented by the following formula (1-A):
The divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and no alicyclic structure is a divalent organic group represented by the following formula (1-B):
The photosensitive resin composition according to claim 1 .
[In formula (1-A), X represents a direct bond, an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond, Y represents an oxygen atom or an NH group, and R ₁ represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxyl group, R ₂ represents a hydrogen atom or a methyl group. * represents a bond.
[In formula (1-B), Z represents a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure. * represents a bond.] the polyimide is a reaction product of a diamine component and a tetracarboxylic acid derivative,
the diamine component contains an aromatic diamine compound having a photopolymerizable group and an aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure;
The photosensitive resin composition according to claim 1 . The aromatic diamine compound having a photopolymerizable group is represented by the following formula (1-a):
The aliphatic diamine compound having 14 to 28 carbon atoms and no alicyclic structure is represented by the following formula (1-b):
The photosensitive resin composition according to claim 3 .
[In formula (1-a), X represents a direct bond, an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond; Y represents an oxygen atom or an NH group; _R1 represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxyl group; and _R2 represents a hydrogen atom or a methyl group.]
[In formula (1-b), Z represents a divalent aliphatic hydrocarbon group having 14 to 28 carbon atoms and not having an alicyclic structure.] 5. The photosensitive resin composition according to claim 4 , wherein X in formula (1-a) represents an ester bond, and Y represents an oxygen atom. 6. The photosensitive resin composition according to claim 4 , wherein R ₁ in the formula (1-a) represents a 1,2-ethylene group. 7. The photosensitive resin composition according to claim 4 , wherein the aliphatic diamine compound represented by formula (1-b) comprises two or more aliphatic diamine compounds having different structural formulas. 8. The photosensitive resin composition according to claim 3 , wherein the tetracarboxylic acid derivative is a tetracarboxylic acid dianhydride. The photosensitive resin composition according to claim 1 , further comprising a photoradical polymerization initiator. The photosensitive resin composition according to claim 1 , further comprising a crosslinkable compound. The photosensitive resin composition according to any one of claims 1 to 10 , which is used for forming an insulating film. 12. The photosensitive resin composition according to claim 1, which is a negative photosensitive resin composition. A resin film which is a fired product of a coating film of the photosensitive resin composition according to any one of claims 1 to 12 . The resin film according to claim 13 , which is an insulating film. A photosensitive resist film comprising a substrate film, a photosensitive resin layer formed from the photosensitive resin composition according to any one of claims 1 to 12 , and a cover film. (1) applying the photosensitive resin composition according to any one of claims 1 to 12 onto a substrate to form a photosensitive resin layer on the substrate;
(2) exposing the photosensitive resin layer to light;
(3) developing the exposed photosensitive resin layer to form a relief pattern;
(4) heat-treating the relief pattern to form a hardened relief pattern;
A method for producing a substrate with a cured relief pattern, comprising: The method for producing a substrate having a cured relief pattern according to claim 16 , wherein the developer used for the development is an organic solvent. 18. A substrate with a cured relief pattern produced by the method of claim 16 or 17 . A semiconductor device comprising a semiconductor element and a cured film provided on the upper or lower part of the semiconductor element, wherein the cured film has a cured relief pattern formed from the photosensitive resin composition according to any one of claims 1 to 12 .