JP7552360B2 - Photosensitive resin composition, photosensitive sheet, cured film, method for producing cured film, interlayer insulating film, and electronic component - Google Patents

Description

The present invention relates to a photosensitive resin composition, a photosensitive sheet, a cured film, a method for producing the cured film, an interlayer insulating film, and an electronic component. More specifically, the present invention relates to a photosensitive resin composition that is suitable for use as a surface protective film or an interlayer insulating film for electronic components such as semiconductor elements, and as an insulating layer for organic electroluminescent elements.

Polyimide resins, which have excellent heat resistance and electrical insulation properties, are typical materials used for surface protection films and interlayer insulating films in semiconductor elements, insulating layers in organic electrolytic elements, and planarizing films in TFT substrates. Furthermore, photosensitive polyimides and their precursors that have been given negative photosensitivity to improve productivity are also being investigated.

In recent years, with the expansion of semiconductor applications and improvements in performance, efforts have been made to reduce costs and increase integration by making manufacturing processes more efficient. As a result, attention has been focused on semiconductor devices that form multilayer metal rewiring. The insulating film for such multilayer metal rewiring is required to have crack resistance against the stress that comes with multilayering, and a low dielectric constant that comes with high integration. Furthermore, in high-frequency communication device applications for high-speed wireless communication, the insulating film is required to have a low dielectric tangent to reduce transmission loss.

As a means of improving crack resistance, a method of introducing a flexible alkylene oxide skeleton into the main chain of polyimide has been proposed (Patent Document 1). As a means of lowering the dielectric constant, a method of using an alicyclic polyimide has been proposed (Patent Document 2). As a means of lowering the dielectric tangent, a soluble polyimide using dimer diamine has been proposed as an adhesive layer (Patent Document 3).

JP 2012-208360 A JP 2009-186861 A JP 2018-203959 A

When conventional technology is applied to a multilayer wiring insulating film for high-frequency communication devices for high-speed wireless communication, for example, in Patent Document 1, the alkylene oxide group improves water absorption, resulting in a poor dielectric constant; in Patent Document 2, the elongation is low, resulting in insufficient crack resistance; and in Patent Document 3, there is an issue that sufficient exposure sensitivity cannot be obtained.

In order to solve the above problems, the present invention relates to the following.
A photosensitive resin composition comprising (A) a polyimide precursor and (B) a photopolymerization initiator, wherein the polyimide precursor (A) contains a resin having a structural unit represented by general formula (11).

In general formula (11), ^X4 represents a tetravalent to hexavalent organic group, and ^Y4 represents a divalent to hexavalent organic group. However, at least one of ^X4 and ^Y4 represents an organic group containing one or more alicyclic structures and a plurality of hydrocarbon structures having 4 or more carbon atoms. Each of the plurality of ^R8 independently represents a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom. However, at least one of the plurality of ^R8 is a monovalent organic group having an ethylenically unsaturated bond. x represents an integer of 2 to 4. Each of the plurality of ^R9 independently represents a monovalent organic group having a carboxyl group, a hydroxyl group, or an ethylenically unsaturated bond. y represents an integer of 0 to 4. * represents a bonding point.

Another aspect of the present invention is as follows:

A photosensitive resin composition comprising (A) a polyimide precursor and (B) a photopolymerization initiator, the polyimide precursor (A) comprising a resin having a structural unit represented by general formula (1).

In the general formula (1), X ¹ represents a tetravalent to hexavalent organic group, and Y ¹ represents a divalent to hexavalent organic group. However, at least one of X ¹ and Y ¹ has an alicyclic hydrocarbon structure having 4 to 8 carbon atoms which may have an unsaturated bond. In the alicyclic hydrocarbon structure, at least four hydrogen atoms are substituted with a hydrocarbon group having 4 to 12 carbon atoms which may have an unsaturated bond. Multiple R ^1s may be the same or different and represent a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom. However, not all R ^1s are hydrogen atoms. p represents an integer of 2 to 4. Multiple R ^2s may be the same or different and represent a carboxyl group, a hydroxyl group, or a monovalent organic group having an ethylenically unsaturated bond. q represents an integer of 0 to 4. * represents a bonding point.

The photosensitive resin composition of the present invention has excellent exposure sensitivity. In addition, the cured film obtained by curing the composition has excellent elongation, low dielectric constant, and low dielectric tangent.

FIG. 2 is an enlarged cross-sectional view of a pad portion of a semiconductor device having bumps. 1A to 1C are diagrams illustrating a detailed method for manufacturing a semiconductor device having bumps. FIG. 1 is a schematic diagram of a coplanar-fed microstrip antenna. 1 is a schematic diagram showing a cross section of a semiconductor package including an IC chip (semiconductor element), a redistribution layer, a sealing resin, and an antenna element.

The present invention provides a photosensitive resin composition containing (A) a polyimide precursor and (B) a photopolymerization initiator. Each component is described below.

The photosensitive resin composition of the present invention contains (A) a polyimide precursor (hereinafter sometimes abbreviated as "component (A)"). By containing component (A), the cured film obtained by curing the photosensitive composition has a low dielectric constant and a low dielectric tangent. (A) polyimide precursor contains a structural unit of the following general formula (11):

In general formula (11), ^X4 represents a tetravalent to hexavalent organic group, and ^Y4 represents a divalent to hexavalent organic group. However, at least one of ^X4 and ^Y4 represents an organic group containing one or more alicyclic structures and a plurality of hydrocarbon structures having 4 or more carbon atoms. Each of the plurality of ^R8 independently represents a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom. However, at least one of the plurality of ^R8 is a monovalent organic group having an ethylenically unsaturated bond. x represents an integer of 2 to 4. Each of the plurality of ^R9 independently represents a monovalent organic group having a carboxyl group, a hydroxyl group, or an ethylenically unsaturated bond. y represents an integer of 0 to 4. * represents a bonding point.

In another aspect of the present invention, (A) the polyimide precursor contains a structure represented by the following general formula (1):

In the general formula (1), X ¹ represents a tetravalent to hexavalent organic group, and Y ¹ represents a divalent to hexavalent organic group. However, at least one of X ¹ and Y ¹ has an alicyclic hydrocarbon structure having 4 to 8 carbon atoms which may have an unsaturated bond. In the alicyclic hydrocarbon structure, at least four hydrogen atoms are substituted with a hydrocarbon group having 4 to 12 carbon atoms which may have an unsaturated bond. Multiple R ^1s may be the same or different and represent a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom. However, not all R ^1s are hydrogen atoms. p represents an integer of 2 to 4. Multiple R ^2s may be the same or different and represent a carboxyl group, a hydroxyl group, or a monovalent organic group having an ethylenically unsaturated bond. q represents an integer of 0 to 4. * represents a bonding point.

In the general formula (1), X ¹ represents a tetravalent to hexavalent organic group and represents a residue of a polyvalent carboxylic acid. Examples of the polyvalent carboxylic acid include tetracarboxylic acid, tetracarboxylic dianhydride, and tetracarboxylic diester dichloride. In this specification, when "-" is used, it means that the upper and lower limit numbers are included unless otherwise specified. Y ¹ represents a divalent to hexavalent organic group and represents a residue of a polyvalent amine. At least one of ^{X 1} and Y ¹ has a structure of an alicyclic hydrocarbon having 4 to 8 carbon atoms that may have an unsaturated bond (hereinafter, sometimes abbreviated as "structure (a)"). However, in the alicyclic hydrocarbon structure, at least four or more hydrogen atoms are substituted with a hydrocarbon group having 4 to 12 carbon atoms that may have an unsaturated bond.

That is, when ^X1 represents a polyvalent carboxylic acid residue having structure (a), when ^Y1 represents a polyvalent amine residue having structure (a), ^X1 and ^Y1 may represent a polyvalent carboxylic acid residue having structure (a) and a polyvalent amine residue having structure (a), respectively. By containing such a structure, the cured film obtained by curing the resin composition has high elongation, low dielectric constant, and low dielectric loss tangent.

Specific examples of the structure (a) are described below. Examples of alicyclic hydrocarbons having 4 to 8 carbon atoms that may have an unsaturated bond include cyclobutyl, cyclocyclobutenyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl, cycloheptenyl, cyclooctyl, and cyclooctenyl groups. Of these, from the viewpoint of thermal stability, cyclohexyl, cyclohexenyl, cycloheptyl, and cycloheptenyl groups are preferred.

Examples of hydrocarbon groups having 4 to 12 carbon atoms and which may have an unsaturated bond include n-butyl, i-butyl, t-butyl, 1-butenyl, 2-butenyl, n-pentyl, i-pentyl, 1-pentenyl, 2-pentenyl, n-hexyl, i-hexyl, 1-hexenyl, 2-hexenyl, n-heptyl, i-heptyl, 1-heptenyl, 2-heptenyl, n-octyl, i-octyl, 1-octenyl, 2-octenyl, nonyl, 1-nonenyl, decanyl, 1-decenyl, undecanyl, 1-undecenyl, dodecanyl, and 1-dodecenyl.

The Y ¹ having the structure (a) is a polyvalent amine residue, and is derived from a residue of a diamine, triamine or a derivative thereof having the structure (a). In addition, by using an amino compound corresponding to this polyvalent amine residue during polymerization, these polyvalent amine residues can be included in the structural unit. Examples of polyvalent amines having the structure (a) include polyvalent amines shown in the following general formula (2) or the following general formula (3). Among them, from the viewpoint of the reliability of the obtained cured film, the polyvalent amines listed in the general formula (2) that do not contain a double bond are preferred. Furthermore, the polyvalent amines represented by the following formula (4) are more preferred from the viewpoints of economy and the elongation of the obtained cured film.

In general formula (2), m represents an integer of 4 to 8. Each W independently represents a structural unit represented by general formula (2a), (2b) or (2c). Of the m Ws, two or more structural units of (2c) are contained, and the sum of the numbers of (2b) and (2c) is 4 or more and 8 or less. Each n or o independently represents an integer of 3 to 11.

In general formula (3), e, f, g, and h are natural numbers, e+f=6 to 17, and g+h=8 to 19. The wavy lines represent carbon-carbon single bonds or carbon-carbon double bonds. However, each molecule contains at least one double bond.

Specific examples of polyamines having the structure (a) include commercially available dimer diamines and trimer triamines such as "Versamine 551" and "Versamine 552" (all trade names manufactured by BASF Ltd.), "Priamine 1071", "Priamine 1073", "Priamine 1074", and "Priamine 1075" (all trade names manufactured by Croda Japan Ltd.). Here, "Versamine 551" and "Priamine 1074" are all dimer diamine compounds containing a compound represented by the following formula (5), and "Versamine 552", "Priamine 1073", and "Priamine 1075" are all dimer diamine compounds containing a compound represented by the above formula (4). "Priamine 1071" is a mixture of dimer diamine and trimer triamine.

^X1 having the structure (a) is a polycarboxylic acid residue, and is derived from a polycarboxylic acid residue having the structure (a) or a residue of a derivative thereof. Examples of polycarboxylic acid compounds that can be the polycarboxylic acid residue include tetracarboxylic acid, hexacarboxylic acid, and octacarboxylic acid. In addition, by using a polycarboxylic acid component corresponding to this polycarboxylic acid residue during polymerization, these polycarboxylic acid residues can be included in the structural unit. Examples of polycarboxylic acids having the structure (a) include the reaction products of the polyamines exemplified in ^Y1 having the structure (a) and trimellitic anhydride chloride. More specifically, the following general formula (6) can be mentioned.

In general formula (6), i, j, k, and l are natural numbers, where i + j = 6 to 17, and k + l = 8 to 19. The wavy lines represent carbon-carbon single bonds or carbon-carbon double bonds.

In the general formula (11), ^X4 represents a tetravalent to hexavalent organic group and represents a residue of a polyvalent carboxylic acid component. Examples of the polyvalent carboxylic acid component include tetracarboxylic acid, tetracarboxylic dianhydride, and tetracarboxylic diester dichloride. ^Y4 represents a divalent to hexavalent organic group and represents a polyvalent amine residue. At least one of ^X4 and ^Y4 represents an organic group containing one or more alicyclic structures and a plurality of hydrocarbon structures having 4 or more carbon atoms (hereinafter, may be abbreviated as "structure (b)"). That is, when ^X4 represents a polyvalent carboxylic acid residue having structure (b), when ^Y4 represents a polyvalent amine residue having (b), ^X4 and ^Y4 may represent a polyvalent carboxylic acid residue having structure (b) and a polyvalent amine residue having structure (b), respectively. By containing such a structure, the cured film obtained by curing the resin composition has high elongation, low dielectric constant, and low dielectric loss tangent.

Specific examples of the structure (b) are described below. Any structure can be used as the alicyclic structure, but bicyclo rings and tricyclo rings having multiple ring structures are preferred from the viewpoint of heat resistance. Specific examples of the alicyclic structure include the organic groups exemplified as specific examples of the alicyclic hydrocarbon of the structure (a) above, as well as a norbornyl group, a norbornel group, and a tricyclodecanyl group. From the viewpoint of heat resistance, a norbornyl group, a norbornel group, and a tricyclodecanyl group are preferred.

Examples of hydrocarbon structures having 4 or more carbon atoms include the organic groups exemplified as specific examples of the hydrocarbon group having 4 to 12 carbon atoms that may have an unsaturated bond of the structure (a) above, as well as a tetradecanyl group, a hexadecanyl group, an octadecanyl group, and an icosanyl group.

^Y4 having the structure (b) is a polyvalent amine residue, and examples of the polyvalent amine compound include the polyvalent amines exemplified in the structure (a) and also the polyvalent amines represented by the following general formula (12).

In general formula (12), u and t each represent an integer from 4 to 16.

^X4 having the structure (b) is a polycarboxylic acid residue. Examples of the polycarboxylic acid include the polycarboxylic acids exemplified in the structure (a) and also the polycarboxylic acids represented by the following general formula (13).

In general formula (13), o and p each represent an integer from 4 to 16.

The (A) component is preferably a resin having structural units represented by the above general formula (1) and the following general formula (7). It is also preferably a resin having structural units represented by the above general formula (11) and the following general formula (7). By having these structural units, it is possible to impart heat resistance and organic solvent solubility while maintaining a low dielectric constant and a low dielectric tangent.

In the general formula (7), ^X2 represents a tetravalent to hexavalent organic group, and ^Y2 represents a divalent to hexavalent organic group. However, at least ^X2 is ^X3 , or ^Y2 is ^Y3 . ^{X3 represents a divalent to hexavalent organic group containing at least one of a bisphenol A skeleton, a biphenyl skeleton, or a hexafluoroisopropylidene skeleton, or at least one of the residues of an acid anhydride represented by the following general formula (8). Y3 represents} a divalent to hexavalent organic group containing at least one of a bisphenol A skeleton, a biphenyl skeleton, or a hexafluoroisopropylidene skeleton, or at least one of the residues of a diamine represented by the following formula (9). A plurality of ^R3s may be the same or different, and represent a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom. However, not all ^R3s are hydrogen atoms. r represents an integer of 2 to 4. A plurality of ^R4s may be the same or different, and represent a monovalent organic group having a carboxyl group, a hydroxyl group, or an ethylenically unsaturated bond. s represents an integer of 0 to 4. * represents a bonding point.

In general formula (8), a represents an integer from 6 to 20. * represents a bonding point.

In general formula (9), * indicates a bond point.

In the general formula (7), ^X2 and ^X3 are derived from a carboxylic acid residue or a residue of a derivative thereof. When ^X2 is ^X3 , examples of the carboxylic acid compound having ^X3 as an acid residue include 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, 2,2',3,3'-biphenyltetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane, 2,2-bis(2,3-dicarboxyphenyl)hexafluoropropane, 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic acid), 4,4'-(4,4'-isopropylidenediphenoxycarbonyl)bis(phthalic acid), and the carboxylic acid anhydrides listed in the general formula (7), and derivatives thereof. Among these, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane, 2,2-bis(2,3-dicarboxyphenyl)hexafluoropropane, and 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic acid) are preferred from the viewpoints of solubility in organic solvents, transparency, and low dielectric constant.

In the general formula (7), ^Y2 and ^Y3 are derived from an amine residue or a residue of a derivative thereof. When ^Y2 is ^Y3 , examples of the amino compound having ^Y3 as an amine residue include 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diaminobiphenyl, 2,2',3,3'-tetramethyl-4,4'-diaminobiphenyl, 3,3',4,4'-tetramethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, bis(3-amino-4-hydroxy)biphenyl, 4,4'-diamino-6,6'-bis(trifluoromethyl)-[1 ,1'-biphenyl]-3,3'-diol, bis(4-aminophenoxy)biphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 2,2'-bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]hexafluoropropane, 2,2'-bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, or the diamine compounds listed in the general formula (8), or derivatives thereof. Among these, from the viewpoints of solubility in organic solvents, transparency, and low dielectric constant, aromatic diamines such as 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and 2,2-bis[4-(4-aminophenoxy)phenyl]propane, and 1,4-cyclohexanediamine, 1,2-bis(aminomethyl)cyclohexane, and 1,3-bis(aminomethyl)cyclohexane in general formula (9) are preferred.

^X1 may be an acid residue other than the polycarboxylic acid residue having the structure (a) as long as it satisfies the requirements of the general formula (1). Also, ^X2 may be an acid residue other than ^X3 as long as it satisfies the requirements of the general formula (7).

Furthermore, ^X4 may be an acid residue other than the polyvalent carboxylic acid residue having the structure (b) so long as the requirement of the general formula (11) is satisfied.

Examples of other carboxylic acid compounds that can serve as acid residues include aromatic tetracarboxylic acids such as pyromellitic acid, 3,3',4,4'-benzophenonetetracarboxylic acid, 2,2',3,3'-benzophenonetetracarboxylic acid, 1,1-bis(3,4-dicarboxyphenyl)ethane, 1,1-bis(2,3-dicarboxyphenyl)ethane, bis(3,4-dicarboxyphenyl)methane, bis(2,3-dicarboxyphenyl)methane, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)thioether, bis(3,4-dicarboxyphenyl)ether, 1,3-bis(3,4-dicarboxyphenoxy)benzene, trimellitic acid (3,4-dicarboxyphenyl), 1,2,5,6-naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 2,3,5,6-pyridinetetracarboxylic acid, and 3,4,9,10-perylenetetracarboxylic acid, and bicyclo[3.1.1. ]hept-2-enetetracarboxylic acid, bicyclo[2.2.2.]octanetetracarboxylic acid, adamantanetetracarboxylic acid, and other aliphatic tetracarboxylic acids are also included.

These acids can be used as they are, or as anhydrides, acid chlorides, or activated esters. Activated ester groups include, but are not limited to, the following structures:

In the formula, A and D represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a trifluoromethyl group, a halogen group, a phenoxy group, or a nitro group. * represents a bonding point.

In addition, by using a silicon atom-containing tetracarboxylic acid such as dimethylsilane diphthalic acid or 1,3-bis(phthalic acid)tetramethyldisiloxane, it is possible to improve adhesion to the substrate and resistance to oxygen plasma and UV ozone treatments used for cleaning, etc. It is preferable to use these silicon atom-containing tetracarboxylic acids in an amount of 1 to 30 mol % of the total acid components.

^Y1 may be an amine residue other than the polyvalent amine residue having the structure (a) as long as it satisfies the requirements of the general formula (1) ^.Y2 may be an amine residue other than ^Y3 as long as it satisfies the requirements of the general formula (7).

Furthermore, ^Y4 may be an amine residue other than the polyvalent amine residue having the structure (a) so long as the requirement of general formula (11) is satisfied.

Other examples of polyvalent amine compounds that can serve as amine residues include aromatic diamines such as m-phenylenediamine, p-phenylenediamine, 3,5-diaminobenzoic acid, 1,5-naphthalenediamine, 2,6-naphthalenediamine, 9,10-anthracenediamine, 4,4'-diaminobenzanilide, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3-carboxy-4,4'-diaminodiphenyl ether, and 3-sulfonic acid-4,4 '-Diaminodiphenyl ether, bis[4-(4-aminophenoxy)phenyl]ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, bis(3-amino-4-hydroxyphenyl)ether, 3,4'-diaminodiphenylmethane, bis(3-amino-4-hydroxyphenyl)methylene, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenyls sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]sulfone, bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]sulfone, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-aminophenoxyphenyl)sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(3-amino-4-hydroxyphenyl)sulfone, 2,2'-bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]propane, 2,2'-bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]propane, 9,9-bis(3-amino-4-hydroxyphenyl)fluorene, 2,7-diaminofluorene, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]fluorene, 9,9 -bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]fluorene, 2-(4-aminophenyl)-5-aminobenzoxazole, 2-(3-aminophenyl)-5-aminobenzoxazole, 2-(4-aminophenyl)-6-aminobenzoxazole, 2-(3-aminophenyl)-6-aminobenzoxazole, 1,4-bis(5-amino-2-benzoxazolyl)benzene, 1,4-bis(6-amino-2-benzoxazolyl)benzene benzene, 1,3-bis(5-amino-2-benzoxazolyl)benzene, 1,3-bis(6-amino-2-benzoxazolyl)benzene, 2,6-bis(4-aminophenyl)benzobisoxazole, 2,6-bis(3-aminophenyl)benzobisoxazole, bis[(3-aminophenyl)-5-benzoxazolyl], bis[(4-aminophenyl)-5-benzoxazolyl], bis[(3-aminophenyl)-6-benzoxazolyl], bis[(4-aminophenyl)-5-benzoxazolyl], N,N'-bis(3-aminobenzoyl)-2,5-diamino-1,4-dihydroxybenzene, N,N'-bis(4-aminobenzoyl)-2,5-diamino-1,4-dihydroxybenzene, N,N'-bis(4-aminobenzoyl)-4,4'-diamino-3,3-dihydroxybiphenyl, N,N'-bis(3-aminobenzoyl)-3,3'-diamino-4,4-dihydroxybiphenyl, N,N'-bis(4-aminobenzoyl)- Examples of the aromatic diamine include, but are not limited to, aromatic diamines such as 3,3'-diamino-4,4-dihydroxybiphenyl, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 4-aminobenzoic acid 4-aminophenyl ester, and 1,3-bis(4-anilino)tetramethyldisiloxane, as well as compounds in which a portion of the hydrogen atoms in these aromatic rings is substituted with an alkyl group or a fluoroalkyl group having 1 to 10 carbon atoms, a halogen atom, or the like.

The polyamine compounds can be used as they are, or as compounds in which the amine moieties are isocyanated or trimethylsilylated. Two or more of these polyamine compounds can also be used in combination.

Examples of aliphatic diamines include ethylenediamine, 1,3-diaminopropane, 2-methyl-1,3-propanediamine, 1,4-diaminobutane, 1,5-diaminopentane, 2-methyl-1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane. Examples of diamines having a siloxane structure include bis(3-aminopropyl)tetramethyldisiloxane and bis(p-aminophenyl)octamethylpentasiloxane, which are preferred because they can improve adhesion to the substrate.

At least one of the R ^1s in the general formula (1), the R ^3s in the general formula (7), and the R ^8s in the general formula (11) is a monovalent organic group having an ethylenically unsaturated bond. The organic group having an ethylenically unsaturated bond can be introduced, for example, by reacting a tetracarboxylic acid dianhydride with an alcohol having an ethylenically unsaturated bond to produce a tetracarboxylic acid diester, which is then subjected to an amide polycondensation reaction with a polyamine compound. Other methods include, for example, a method in which a polyamic acid is produced from an acid dianhydride and a diamine, and then trifluoroacetic acid and an alcohol having an ethylenically unsaturated bond are reacted with the amic acid.

As a method for producing the above-mentioned tetracarboxylic acid diester, the above-mentioned acid dianhydride and alcohol can be reacted in a solvent as is, but from the viewpoint of reactivity, it is preferable to use a reaction activator. Examples of reaction activators include tertiary amines such as pyridine, dimethylaminopyridine, triethylamine, N-methylmorpholine, and 1,8-diazabicycloundecene. The amount of reaction activator added is preferably 3 mol% to 300 mol% relative to the acid anhydride group to be reacted, and more preferably 20 mol% to 150 mol%. In addition, a small amount of polymerization inhibitor may be used to prevent the ethylenically unsaturated bond site from crosslinking during the reaction. This allows the reaction to be accelerated by heating at a temperature of 120°C or less in the reaction between alcohols having ethylenically unsaturated bonds with low reactivity and tetracarboxylic acid dianhydride. Examples of polymerization inhibitors include phenolic compounds such as hydroquinone, 4-methoxyphenol, t-butylpyrocatechol, and bis-t-butylhydroxytoluene. The amount of the polymerization inhibitor to be added is preferably 0.1 mol % or more and 5 mol % or less of the phenolic hydroxyl group of the polymerization inhibitor relative to the ethylenically unsaturated bonds of the alcohols.

There are various methods for the aforementioned amide polycondensation reaction. These include a method in which a tetracarboxylic acid diester is converted into an acid chloride and then reacted with a diamine, a method using a carbodiimide-based dehydration condensation agent, and a method in which a tetracarboxylic acid diester is converted into an activated ester and then reacted with a diamine. Among these, the method using an activated ester as an intermediate is preferred because it has good reactivity regardless of whether an aromatic diamine or an aliphatic diamine is selected as the monomer.

Examples of the alcohols having an ethylenically unsaturated bond include (meth)acrylates having a hydroxyl group or unsaturated fatty acid modified alcohols. Examples of (meth)acrylates having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 1-(meth)acryloyloxy-2-propyl alcohol, 2-(meth)acrylamidoethyl alcohol, methylol vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl (meth)acrylate, 2-hydroxy-3-butoxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-hydroxy-3-t-butoxypropyl (meth)acrylate, 2-hydroxy-3-cyclohexylalkoxypropyl (meth)acrylate, 2-hydroxy-3-cyclohexyloxypropyl (meth)acrylate, and 2-hydroxy-3-cyclohexyloxypropyl (meth)acrylate. Examples of the ethylenically unsaturated bond include alcohols having one ethylenically unsaturated bond and one hydroxyl group, such as glycerin-1,3-di(meth)acrylate, glycerin-1,2-di(meth)acrylate, trimethylolpropane di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, glycerin-1-allyloxy-3-methacrylate, glycerin-1-allyloxy-2-methacrylate, 2-ethyl-2-(hydroxymethyl)propane-1,3-diylbis(2-methacrylate), and 2-(acryloyloxy)-2-(hydroxymethyl)butyl methacrylate. Here, "(meth)acrylate" refers to methacrylate or acrylate. The same applies to similar notations.

Examples of unsaturated fatty acid modified alcohols include unsaturated fatty acid modified alcohols having 6 or more carbon atoms. From the viewpoint of exposure sensitivity, alcohols having an unsaturated group at the end or a double bond in a cis structure are preferred, and from the viewpoint of dielectric constant and dielectric tangent, alcohols having 12 or more carbon atoms are preferred. Specific examples of unsaturated fatty acid modified alcohols include 5-hexen-1-ol, 3-hexen-1-ol, 6-hepten-1-ol, cis-5-octen-1-ol, cis-3-octen-1-ol, cis-3-nonen-1-ol, cis-6-nonen-1-ol, 9-decane-1-ol, cis-4-decane-1-ol, 10-undecen-1-ol, 11-dodecane-1-ol, elidolinoleyl alcohol, oleyl alcohol, linoleyl alcohol, linolenyl alcohol, and erucyl alcohol. Of these, oleyl alcohol, linoleyl alcohol, and linolenyl alcohol are preferred from the viewpoints of the dielectric properties and exposure sensitivity of the resulting cured film.

When reacting an acid anhydride with an alcohol having an ethylenically unsaturated bond, other alcohols may be used at the same time. The other alcohols can be appropriately selected according to various purposes, such as adjusting the exposure sensitivity or adjusting the solubility in organic solvents. Specifically, aliphatic alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, i-butanol, t-butanol, 1-pentanol, 2-pentanol, 3-pentanol, and i-pentanol, and monoalcohols derived from alkylene oxides such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, and tripropylene glycol monobutyl ether, can be mentioned.

The organic group having an ethylenically unsaturated bond may be introduced into R ¹ in general formula (1), R ³ in general formula (7), and a plurality of R ⁸ in general formula (11) via ionic bond. An example of a method for introducing an organic group having an ethylenically unsaturated bond by ionic bond is a method of reacting a polyamic acid obtained by reacting an acid dianhydride with a diamine with a tertiary amine having an ethylenically unsaturated bond. An example of the tertiary amine having an ethylenically unsaturated bond is a compound represented by the following general formula (10).

In formula (10), ^R5 represents a hydrogen atom or a methyl group. ^R6 and ^R7 each independently represent any one of a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an s-butyl group, a t-butyl group, and a phenyl group. b represents an integer of 1 to 10.

Of these, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, and diethylaminopropyl (meth)acrylate are preferred because they tend to increase exposure sensitivity.

In addition, in order to improve the storage stability of the photosensitive resin composition of the present invention and to exhibit various functions, the main chain end of component (A) may be blocked with a terminal blocking agent. Examples of terminal blocking agents include monoamines, acid anhydrides, monocarboxylic acids, monoacid chloride compounds, and monoactive ester compounds. In addition, in the later stage of the amide polycondensation reaction described above, monoalcohols can also be used as terminal blocking agents. In addition, by blocking the ends of the resin with a terminal blocking agent having a hydroxyl group, a carboxyl group, a sulfonic acid group, a thiol group, a vinyl group, an ethynyl group, or an allyl group, the exposure sensitivity and the mechanical properties of the resulting cured film can be easily adjusted to a preferred range.

From the viewpoint of solubility in the developer and mechanical properties of the resulting cured film, the introduction ratio of the terminal blocking agent is preferably 0.1 mol% or more and 60 mol% or less, and particularly preferably 5 mol% or more and 50 mol% or less. Multiple terminal blocking agents may be reacted to introduce multiple different terminal groups.

As the monoamine used as the terminal blocking agent, known compounds can be used, but preferred are aniline, 2-ethynylaniline, 3-ethynylaniline, 4-ethynylaniline, 1-hydroxy-7-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 3-aminobenzoic acid, 3-aminophenol, 3-aminothiophenol, etc. Two or more of these may be used.

As the acid anhydride, monocarboxylic acid, monoacid chloride compound, and monoactive ester compound, known compounds can be used, but acid anhydrides such as phthalic anhydride, maleic anhydride, nadic anhydride, cyclohexanedicarboxylic anhydride, and 3-hydroxyphthalic anhydride, and itaconic anhydride are preferred. Two or more of these may be used.

Monoalcohols used as end-capping agents include those exemplified as alcohols that react with the acid anhydrides mentioned above.

In addition, the monomer containing the structure (a) and the terminal blocking agent introduced into the component (A) used in the present invention can be easily detected by the following method. For example, the resin into which the terminal blocking agent has been introduced is dissolved in an acidic solution, decomposed into structural units, amine components and acid anhydride components, and the resulting mixture is subjected to gas chromatography (GC) or NMR measurement, whereby the terminal blocking agent used in the present invention can be easily detected. In addition, the GC measurement is performed simultaneously with an external standard substance whose peak does not overlap with each component, and the integral value of each peak of the chromatogram is compared with the external standard substance, whereby the molar ratio of each monomer including the terminal blocking agent can be estimated. Separately, the resin component into which the terminal blocking agent has been introduced can also be easily detected by directly measuring the resin component with a pyrolysis gas chromatograph (PGC), infrared spectrum, ¹ H-NMR spectrum, ¹³ C-NMR spectrum, and two-dimensional NMR spectrum. In this case, the molar ratio of each monomer can be analyzed from the integral value of the infrared spectrum, ¹ H-NMR spectrum, or two-dimensional NMR.

The (A) component in the present invention preferably has a weight average molecular weight of 5,000 or more and 100,000 or less. By making the weight average molecular weight 5,000 or more in terms of polystyrene by GPC (gel permeation chromatography), mechanical properties such as elongation after curing, strength at break, and elastic modulus can be improved. On the other hand, by making the weight average molecular weight 100,000 or less, developability can be improved. In order to obtain mechanical properties, 20,000 or more is more preferable. In addition, when the (A) component contains two or more types of resins, it is sufficient that the weight average molecular weight of at least one of them is within the above range.

In addition, it is preferable to polymerize the component (A) used in the present invention using a solvent. The type of polymerization solvent is not particularly limited as long as it can dissolve the raw material monomers, that is, the acid component, the amine component, the alcohol, and the catalyst. Examples of the monomer include amides such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N,N'-dimethylpropyleneurea, N,N-dimethylisobutyric acid amide, and methoxy-N,N-dimethylpropionamide; cyclic esters such as γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, and α-methyl-γ-butyrolactone; carbonates such as ethylene carbonate and propylene carbonate; glycols such as triethylene glycol; phenols such as m-cresol and p-cresol; acetophenone, 1,3-dimethyl-2-imidazolidinone, sulfolane, and dimethyl sulfoxide.

The photosensitive resin composition of the present invention contains (B) a photopolymerization initiator. By containing (B) a photopolymerization initiator, pattern processing becomes possible through exposure and development processes. (B) The photopolymerization initiator is not particularly limited as long as it is a compound that generates radicals upon exposure, but alkylphenone compounds, aminobenzophenone compounds, diketone compounds, ketoester compounds, phosphine oxide compounds, oxime ester compounds and benzoic acid ester compounds are preferred because they have excellent sensitivity, stability and ease of synthesis. Among them, alkylphenone compounds and oxime ester compounds are preferred from the viewpoint of sensitivity, and oxime ester compounds are particularly preferred. In addition, when the processed film thickness is a thick film of 5 μm or more, phosphine oxide compounds are preferred from the viewpoint of resolution.

Examples of alkylphenone compounds include α-aminoalkylphenone compounds such as 2-methyl-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl} α-hydroxyalkylphenone compounds such as 4-benzoyl-4-methylphenyl ketone, 2,3-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p-t-butyl dichloroacetophenone, benzyl methoxyethyl acetal, 2,3-diethoxyacetophenone, benzyl dimethyl ketal, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and other α-alkoxyalkylphenone compounds; acetophenone compounds such as acetophenone and p-t-butyl dichloroacetophenone. Among these, α-aminoalkylphenone compounds such as 2-methyl-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, or 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 are preferred because of their high sensitivity.

Examples of phosphine oxide compounds include 6-trimethylbenzoylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethylpentyl)-phosphine oxide.

Examples of oxime ester compounds include 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-methoxycarbonyl)oxime, 1-phenyl-2-(benzoyloximino)-1-propanone, 2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], 1-phenyl-1,2-butadione-2-(o-methoxycarbonyl)oxime, 1,3-diphenylpropanetrione-2-(o-ethoxycarbonyl)oxime, ethoxycarbonyl ... Examples of the oxime include non, 1-phenyl-1,2-propanedione-2-(o-benzoyl)oxime, 1-phenyl-3-ethoxypropanetrione-2-(o-benzoyl)oxime, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetyloxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetyloxime), NCI-831, NCI-930 (all manufactured by ADEKA), OXE-03, OXE-04 (all manufactured by BASF). Among these, from the viewpoint of sensitivity, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime), 2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], NCI-831, NCI-930, OXE-03 and OXE-04 are preferred.

Examples of the aminobenzophenone compound include 4,4-bis(dimethylamino)benzophenone and 4,4-bis(diethylamino)benzophenone.
The diketone compound includes benzil.
Examples of the ketoester compound include methyl benzoylformate and ethyl benzoylformate.

Examples of benzoic acid ester compounds include methyl o-benzoylbenzoate, ethyl p-dimethylaminobenzoate, 2-ethylhexyl 4-(dimethylamino)benzoate, and ethyl p-diethylaminobenzoate.

Other specific examples of the photopolymerization initiator (B) include benzophenone, 4-benzoyl-4'-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 4-phenylbenzophenone, 4,4-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, alkylated benzophenone, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benzenemethanaminium bromide, (4-benzoylbenzyl)trimethylammonium chloride, 2-hydroxy-3-(4-benzoylphenoxy)-N,N,N-trimethyl-1-propenaminium chloride monohydrate, thioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, and 2-methylthioxanthone. thioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, anthraquinone, 2-t-butylanthraquinone, 2-aminoanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzsubete p-azidobenzalacetophenone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis(p-azidobenzylidene)cyclohexane, 2,6-bis(p-azidobenzylidene)-4-methylcyclohexanone, naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, benzthiazole disulfide, triphenylphosphine, carbon tetrabromide, and tribromophenyl sulfone.

The content of the (B) photopolymerization initiator is preferably 0.5 parts by mass or more and 20 parts by mass or less, where the sum of the (A) component and the (D) compound having two or more ethylenically unsaturated bonds contained as necessary is taken as 100 parts by mass, because this provides sufficient sensitivity and suppresses the amount of outgassing during thermal curing. Of these, 1.0 parts by mass or more and 10 parts by mass or less is more preferable.

The photosensitive resin composition of the present invention may contain a sensitizer for the purpose of enhancing the function of the photopolymerization initiator (B). By including a sensitizer, it is possible to improve the sensitivity and adjust the photosensitive wavelength. Examples of sensitizers include, but are not limited to, bis(dimethylamino)benzophenone, bis(diethylamino)benzophenone, diethylthioxanthone, N-phenyldiethanolamine, N-phenylglycine, 7-diethylamino-3-benzoylcoumarin, 7-diethylamino-4-methylcoumarin, N-phenylmorpholine, and derivatives thereof.

It is preferable that the photosensitive resin composition of the present invention further contains (C) a compound having two or more ethylenically unsaturated bonds (hereinafter, sometimes abbreviated as "component (C)"). However, component (C) has a molecular weight of 100 or more and 2000 or less. By containing component (C), the crosslinking density during exposure is improved, thereby further improving the exposure sensitivity, and contributing to reducing the amount of exposure and the loss of the developed film.

Component (C) may contain a known (meth)acrylate compound, and polyfunctional (meth)acrylates containing an alicyclic structure are particularly preferred because they can achieve both a low dielectric constant, a low dielectric tangent, and a high level of exposure sensitivity.

Examples of polyfunctional (meth)acrylates containing an alicyclic structure include diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,3-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, dicyclodecane di(meth)acrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, dimethylol-tricyclodecane di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate, 1,3,5-adamantanetriol di(meth)acrylate, 1,3,5-adamantanetriol tri(meth)acrylate, 1,4 -Cyclohexanedimethanol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, tetrapentaerythritol nona(meth)acrylate, tetrapentaerythritol deca(meth)acrylate acrylate, pentaerythritol undeca(meth)acrylate, pentaerythritol dodeca(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, (2-(meth)acryloyloxypropoxy)-3-methylphenyl]fluorene or 9,9-bis[4-(2-(meth)acryloyloxyethoxy)-3,5-dimethylphenyl]fluorene. Among them, dimethylol-tricyclodecane di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate, 1,3,5-adamantanetriol di(meth)acrylate, 1,3,5-adamantanetriol tri(meth)acrylate, 1,4-cyclohexanedimethanol di(meth)acrylate, and the like can be mentioned.

Other compounds of component (C) include, for example, epoxy (meth)acrylate obtained by reacting a polyfunctional epoxy compound with (meth)acrylic acid. Epoxy (meth)acrylate imparts hydrophilicity and can be used to improve alkaline developability. Examples of polyfunctional epoxy compounds include the following compounds. These polyfunctional epoxy compounds are preferred because they have excellent heat resistance and chemical resistance.

The content of component (C) is preferably 5 parts by weight or more and 100 parts by weight or less, and more preferably 10 parts by weight or more and 40 parts by weight or less, per 100 parts by weight of component (A). When the content is within this range, it becomes easier to obtain the effects of improving exposure sensitivity, low dielectric constant, and low dielectric tangent.

The photosensitive resin composition of the present invention may contain an antioxidant. By containing an antioxidant, yellowing of the cured film during the subsequent heat treatment and deterioration of mechanical properties such as elongation can be suppressed. In addition, it is preferable because the oxidation of the metal material can be suppressed by the rust prevention effect on the metal material.

The antioxidant is preferably a hindered phenol-based antioxidant or a hindered amine-based antioxidant.
Examples of the hindered phenol-based antioxidant include, but are not limited to, Irganox 245, Irganox 3114, Irganox 1010, Irganox 1098, Irganox 1135, Irganox 259, Irganox 1035 (all trade names, manufactured by BASF Ltd.), or 2,6-di(t-butyl)-p-cresol.

Examples of hindered amine antioxidants include TINUVIN 144, TINUVIN 292, TINUVIN 765, TINUVIN 123 (all trade names, manufactured by BASF Ltd.), 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, 2,2,6,6-tetramethyl-4-piperidyl methacrylate, and tetrakis(1,2,2,6,6-pentamethyl-4-pyridyl)butane-1,2,3,4-tetracarboxylate.

Other antioxidants include phenol, catechol, resorcinol, hydroquinone, 4-t-butylcatechol, 2,6-di(t-butyl)-p-cresol, phenothiazine, and 4-methoxyphenol. The amount of antioxidant added is preferably 0.1 to 10.0 parts by mass, and more preferably 0.3 to 5.0 parts by mass, per 100 parts by mass of component (A). When the amount is within this range, the developability and the effect of suppressing discoloration due to heat treatment can be maintained at an appropriate level.

The photosensitive resin composition of the present invention may contain a heterocyclic compound containing a nitrogen atom. By containing a heterocyclic compound containing a nitrogen atom, high adhesion can be obtained on a metal substrate that is easily oxidized, such as copper, aluminum, or silver. Although the mechanism is unclear, it is speculated that the nitrogen atom interacts with the metal surface due to its metal coordination ability, and that the bulkiness of the heterocycle stabilizes this interaction.

Heterocyclic compounds containing nitrogen atoms include imidazole, pyrazole, indazole, carbazole, pyrazoline, pyrazolidine, triazole, tetrazole, pyridine, piperidine, pyrimidine, pyrazine, triazine, cyanuric acid, isocyanuric acid, and derivatives thereof.

As heterocyclic compounds containing a nitrogen atom, from the viewpoint of reactivity with metals, 1H-benzotriazole, 4-methyl-1H-methylbenzotriazole, 5-methyl-1H-methylbenzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, etc. are preferred.

The amount of the nitrogen-containing heterocyclic compound added is preferably 0.01 to 5.0 parts by weight, more preferably 0.05 to 3.0 parts by weight, per 100 parts by weight of component (A). When the amount is within this range, the developability and the stabilization effect of the base metal can be maintained at an appropriate level.

The photosensitive resin composition of the present invention may contain a solvent. Examples of the solvent include polar aprotic solvents such as N-methyl-2-pyrrolidone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, 1,3-dimethyl-2-imidazolidinone, N,N'-dimethylpropyleneurea, N,N-dimethylisobutyric acid amide, and methoxy-N,N-dimethylpropionamide; ethers such as tetrahydrofuran, dioxane, propylene glycol monomethyl ether, and propylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone, and diisobutyl ketone; esters such as ethyl acetate, butyl acetate, isobutyl acetate, propyl acetate, propylene glycol monomethyl ether acetate, and 3-methyl-3-methoxybutyl acetate; alcohols such as ethyl lactate, methyl lactate, diacetone alcohol, and 3-methyl-3-methoxybutanol; and aromatic hydrocarbons such as toluene and xylene. Two or more of these may be contained.

The content of the solvent is preferably 100 parts by mass or more per 100 parts by mass of component (A) in order to dissolve the composition, and is preferably 1,500 parts by mass or less in order to form a coating film with a thickness of 1 μm or more.

If necessary, the photosensitive resin composition of the present invention may contain surfactants, esters such as ethyl lactate and propylene glycol monomethyl ether acetate, alcohols such as ethanol, ketones such as cyclohexanone and methyl isobutyl ketone, and ethers such as tetrahydrofuran and dioxane in order to improve wettability with the substrate.

In addition, in order to enhance adhesion to the substrate, the photosensitive resin composition of the present invention may contain a silane coupling agent as a silicon component within a range that does not impair storage stability. Examples of silane coupling agents include trimethoxyaminopropylsilane, trimethoxycyclohexylepoxyethylsilane, trimethoxyvinylsilane, trimethoxythiolpropylsilane, trimethoxyglycidyloxypropylsilane, tris(trimethoxysilylpropyl)isocyanurate, triethoxyaminopropylsilane, triethoxycyclohexylepoxyethylsilane, triethoxyvinylsilane, triethoxythiolpropylsilane, triethoxyglycidyloxypropylsilane, tris(triethoxysilylpropyl)isocyanurate, and a reaction product of trimethoxyaminopropylsilane or triethoxyaminopropylsilane with an acid anhydride. The reaction product can be used in the form of an amide acid or in the form of an imidization. Examples of the acid anhydride to be reacted include succinic anhydride, maleic anhydride, nadic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-benzophenonetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, and 4,4'-oxydiphthalic dianhydride. The preferred content of the silane coupling agent is 0.01 to 10 parts by mass relative to 100 parts by mass of component (A).

Next, we will explain the shape of the photosensitive resin composition of the present invention.

The photosensitive resin composition of the present invention is not limited in shape as long as it contains the component (A) and the photopolymerization initiator (B), and may be, for example, in the form of a paste or a sheet.

The photosensitive sheet of the present invention refers to a sheet-like material that is not completely hardened and is obtained by applying the photosensitive resin composition of the present invention onto a support and drying it at a temperature and for a time range that allows the solvent to evaporate, and is soluble in an organic solvent or an alkaline aqueous solution.

The support is not particularly limited, but various commercially available films such as polyethylene terephthalate (PET) film, polyphenylene sulfide film, and polyimide film can be used. The joint surface between the support and the photosensitive resin composition may be surface-treated with silicone, a silane coupling agent, an aluminum chelating agent, polyurea, etc. to improve adhesion and peelability. The thickness of the support is not particularly limited, but is preferably in the range of 10 to 100 μm from the viewpoint of workability. Furthermore, in order to protect the film surface of the photosensitive composition obtained by coating, a protective film may be provided on the film surface. This makes it possible to protect the surface of the photosensitive resin composition from contaminants such as dust and dirt in the air.

Examples of methods for applying the photosensitive resin composition to a support include spin coating using a spinner, spray coating, roll coating, screen printing, blade coater, die coater, calendar coater, meniscus coater, bar coater, roll coater, comma roll coater, gravure coater, screen coater, and slit die coater. The coating thickness varies depending on the coating method, the solids concentration of the composition, and the viscosity, but it is usually preferable that the coating thickness after drying is 0.5 μm or more and 100 μm or less from the viewpoint of coating uniformity, etc.

For drying, an oven, a hot plate, infrared rays, etc. can be used. The drying temperature and drying time may be within a range that allows the solvent to volatilize, and it is preferable to set the drying temperature and time appropriately so that the photosensitive resin composition is in an uncured or semi-cured state. Specifically, drying is preferably performed at a temperature in the range of 40°C to 150°C for one minute to several tens of minutes. Alternatively, the temperature may be increased stepwise by combining these temperatures, for example, heat treatment may be performed at 80°C and 90°C for two minutes each.

Next, we will explain a method for forming a relief pattern of a cured film using the photosensitive resin composition or photosensitive sheet of the present invention.

The photosensitive resin composition of the present invention is applied onto a substrate, or the photosensitive sheet is laminated onto a substrate. The substrate may be, but is not limited to, a copper-plated metal substrate or a silicon wafer, and the material may be, for example, ceramics or gallium arsenide. Coating methods include rotary coating using a spinner, spray coating, and roll coating. The coating thickness varies depending on the coating method, the solids concentration of the composition, the viscosity, etc., but is usually applied so that the film thickness after drying is 0.1 to 150 μm.

To enhance the adhesion between the substrate and the photosensitive resin composition, the substrate can be pretreated with the aforementioned silane coupling agent. For example, a solution is prepared by dissolving 0.5 to 20% by mass of the silane coupling agent in a solvent such as isopropanol, ethanol, methanol, water, tetrahydrofuran, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethyl lactate, or diethyl adipate. The substrate is then surface-treated with the solution by spin coating, immersion, spray coating, steam treatment, or the like. In some cases, a heat treatment up to 50°C to 300°C is then performed to promote the reaction between the substrate and the silane coupling agent.

Next, the photosensitive resin composition is applied, or the substrate laminated with the photosensitive sheet of the present invention is dried to obtain a photosensitive resin composition film. Drying is preferably carried out using an oven, a hot plate, infrared rays, etc., at a temperature in the range of 50°C to 150°C for one minute to several hours. Note that in the case of a photosensitive sheet, it is not necessarily necessary to go through a drying process.

Next, this photosensitive resin composition film is exposed to actinic radiation through a mask having a desired pattern. Actinic radiation used for exposure includes ultraviolet light, visible light, electron beams, and X-rays, but in the present invention, it is preferable to use i-rays (365 nm), h-rays (405 nm), and g-rays (436 nm) from a mercury lamp.

Next, the exposed photosensitive resin composition film may be subjected to a post-exposure bake (PEB) process, if necessary. The PEB process is preferably carried out in an oven, on a hot plate, with infrared rays, or the like, at a temperature in the range of 50°C to 150°C for one minute to several hours.

Next, the photosensitive resin film after exposure is developed. To form a resin pattern, after exposure, the unexposed parts are removed using a developer. The developer used for development is preferably a good solvent for the photosensitive resin composition, or a combination of the good solvent and a poor solvent. For example, N-methylpyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, etc. are preferred as good solvents. Preferred poor solvents are toluene, xylene, methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, water, etc. When a mixture of a good solvent and a poor solvent is used, it is preferred to adjust the ratio of the poor solvent to the good solvent depending on the solubility of the polymer in the photosensitive resin composition. In addition, two or more types of each solvent, for example, several types, can be used in combination.

In addition, when the photosensitive resin composition is soluble in an alkaline aqueous solution, alkaline aqueous solution development may be performed. The developer used for development dissolves and removes the alkaline aqueous solution soluble polymer, and is typically an alkaline aqueous solution in which an alkaline compound is dissolved. Examples of alkaline compounds include tetramethylammonium hydroxide, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, dimethylaminoethyl acetate, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, and hexamethylenediamine. In some cases, these aqueous alkaline solutions may contain polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, γ-butyrolactone, and dimethylacrylamide; alcohols such as methanol, ethanol, and isopropanol; esters such as ethyl lactate and propylene glycol monomethyl ether acetate; and ketones such as cyclopentanone, cyclohexanone, isobutyl ketone, and methyl isobutyl ketone, either alone or in combination.

After development, it is preferable to rinse with an organic solvent or water. When using an organic solvent, in addition to the above-mentioned developer, examples of the developer include ethylene glycol monomethyl ether acetate and propylene glycol monomethyl ether acetate. When using water, alcohols such as ethanol and isopropyl alcohol, and esters such as ethyl lactate and propylene glycol monomethyl ether acetate may also be added to the water for rinsing.

Next, the photosensitive resin film after development is heat-treated. After development, a temperature of 150°C to 400°C is applied to proceed with the thermal crosslinking reaction and harden the film. This heat treatment is carried out for 5 minutes to 5 hours by selecting a certain temperature and gradually increasing the temperature, or by selecting a certain temperature range and continuously increasing the temperature. As an example, heat treatment is performed at 130°C and 200°C for 30 minutes each. The lower limit of the curing conditions in this invention is preferably 170°C or higher, but more preferably 180°C or higher to sufficiently advance the hardening. There is no particular limit on the upper limit of the curing conditions, but from the viewpoint of suppressing film shrinkage and stress, 280°C or lower is preferable, 250°C or lower is more preferable, and 230°C or lower is even more preferable. In addition, for the purpose of increasing the glass transition point or thermal decomposition temperature, the lower limit is preferably 250°C or higher, and the upper limit is preferably 350°C or lower.

The cured film formed from the photosensitive resin composition of the present invention can be used as an insulating film or protective film that constitutes electronic components.

Here, examples of electronic components include active components that have semiconductors, such as transistors, diodes, integrated circuits (ICs), and memories, and passive components, such as resistors, capacitors, inductors, and antenna elements. Electronic components that use semiconductors are also called semiconductor devices.

Specific examples of cured films in electronic components include passivation films for semiconductors, surface protective films for semiconductor elements and TFTs (Thin Film Transistors), interlayer insulating films such as interlayer insulating films between rewirings in multilayer wiring for high-density mounting of 2 to 10 layers, insulating films and protective films for touch panel displays, and insulating layers for organic electroluminescent elements, but are not limited to these and can have a variety of structures.

The substrate surface on which the cured film is formed can be selected appropriately depending on the application and process, but examples include silicon, ceramics, glass, metal, epoxy resin, etc., and multiple of these may be arranged on the same surface.

Next, an application example of a semiconductor device having bumps using a cured film obtained by curing the photosensitive resin composition of the present invention will be described with reference to the drawings. FIG. 1 is an enlarged cross-sectional view of a pad portion of a semiconductor device having bumps of the present invention. As shown in FIG. 1, a passivation film 3 is formed on an aluminum (hereinafter abbreviated as Al) pad 2 for input/output on a silicon wafer 1, and a via hole is formed in the passivation film 3. An insulating film 4 is formed on the cured film as a pattern obtained by curing the photosensitive resin composition of the present invention, and a metal (Cr, Ti, etc.) film 5 is formed so as to be connected to the Al pad 2, and a metal wiring (Al, Cu, etc.) 6 is formed by electrolytic plating or the like. The metal film 5 etches the periphery of the solder bump 10 to insulate each pad. A barrier metal 8 and a solder bump 10 are formed on the insulated pad. The cured film obtained by curing the photosensitive resin composition of the insulating film 7 can be processed into a thick film at the scribe line 9.

Next, the detailed method of manufacturing the semiconductor device is described in FIG. 2. As shown in FIG. 2, 2a, an Al pad 2 for input/output and a passivation film 3 are formed on a silicon wafer 1, and an insulating film 4 is formed as a pattern of a cured film of the photosensitive resin composition of the present invention. Then, as shown in FIG. 2, 2b, a metal (Cr, Ti, etc.) film 5 is formed so as to be connected to the Al pad 2, and as shown in FIG. 2, 2c, a metal wiring 6 is formed by a plating method. Next, as shown in FIG. 2, 2d', the photosensitive resin composition of the present invention before curing is applied, and a photolithography process is performed to form an insulating film 7 as a pattern as shown in FIG. 2, 2d. At this time, the photosensitive resin composition of the insulating film 7 before curing is processed into a thick film at the scribe line 9. When forming a multilayer wiring structure of three or more layers, the above steps can be repeated to form each layer.

Next, as shown in 2e and 2f in Figure 2, a barrier metal 8 and solder bumps 10 are formed. Then, dicing is performed along the final scribe line 9 to separate each chip. If the insulating film 7 is not patterned along the scribe line 9 or if residue remains, cracks will occur during dicing, which will affect the reliability evaluation of the chip. For this reason, being able to provide pattern processing that is excellent for thick film processing, as in the present invention, is extremely preferable in order to obtain high reliability of semiconductor devices.

Next, an antenna element using a cured film obtained by curing the photosensitive resin composition of the present invention will be described. Figure 3 is a schematic diagram of a coplanar feed type microstrip antenna, which is a type of planar antenna. 3a shows a cross-sectional view, and 3b shows a top view. First, the formation method will be described. The photosensitive resin composition of the present invention is applied onto copper foil, pre-baked, exposed to light, and then laminated with copper foil and thermally cured to form a cured film having copper foil on both sides. After that, patterning is performed by the subtractive method, and an antenna element having an antenna pattern of copper wiring of a microstrip line (MSL) as shown in Figure 3 is obtained.

Next, the antenna pattern in FIG. 3 will be described. In 3a, 35 indicates the ground (all over), and 36 indicates an insulating film that becomes the antenna substrate. The upper layers 31 to 33 indicate the cross section of the antenna wiring obtained by the patterning. The ground wiring thickness J and the antenna wiring thickness K can be any thickness depending on the impedance design, but are generally 2 to 20 μm. In 3b, 31 indicates the antenna part, 32 indicates a matching circuit, 33 indicates an MSL feed line, and 34 indicates a feed point. In order to match the impedance of the antenna part 31 and the feed line 33, the length M of the matching circuit 32 has a length of 1/4 λr (λr = (wavelength of transmitted radio wave) / (dielectric constant of insulating material) ^1/2 ). In addition, the width W and length L of the antenna part 31 are designed to be 1/2 λr. The antenna part length L may be 1/2 λr or less depending on the impedance design. The cured film of the present invention has a low dielectric constant and a low dielectric loss tangent, so that it is possible to provide an antenna element with high efficiency and high gain. In addition, due to these characteristics, an antenna element using the insulating film of the present invention is suitable as a high-frequency antenna, and a small antenna element can be formed by making the area of the antenna part (=L×W) 1000 mm2 or ^less . In this way, a high-efficiency, high-gain, small-sized antenna element for high frequencies can be obtained.

Next, a semiconductor package having an IC chip (semiconductor element), a rewiring layer, a sealing resin, and an antenna wiring will be described. FIG. 4 is a schematic diagram of a cross section of a semiconductor package having an IC chip (semiconductor element), a rewiring, a sealing resin, and an antenna element. On the electrode pad 402 of the IC chip 401, a rewiring layer (2 copper layers, 3 insulating layers) is formed by copper wiring 409 and an insulating film 410 formed by the cured film of the present invention. A barrier metal 411 and a solder bump 412 are formed on the pad of the rewiring layer (copper wiring 409 and insulating film 410). In order to seal the IC chip, a first sealing resin 408 made of the cured film of the present invention is formed, and a copper wiring 409 serving as a ground for the antenna is further formed thereon. A first via wiring 407 is formed to connect the ground 406 and the rewiring layer (copper wiring 409 and insulating film 410) through a via hole formed in the first sealing resin 408. A second sealing resin 405 made of the cured film of the present invention is formed on the first sealing resin 408 and the ground wiring 406, and a planar antenna wiring 404 is formed thereon. A second via wiring 403 is formed through a via hole formed in the first sealing resin 408 and the second sealing resin 405 to connect the planar antenna wiring 404 and the rewiring layer (copper wiring 409 and insulating film 410). The thickness of each insulating film 410 is preferably 10 to 20 μm, and the first sealing resin and the second sealing resin are preferably 50 to 200 μm and 100 to 400 μm, respectively. Since the cured film of the present invention has a low dielectric constant and a low dielectric loss tangent, a semiconductor package having the obtained antenna element is highly efficient, has a high gain, and has a small transmission loss within the package.

In other words, the electronic component of the present invention is an electronic component including at least one or more antenna wirings and an antenna element having the cured film of the present invention, wherein the antenna wiring includes one or more types selected from the group consisting of a meandering loop antenna, a coiled loop antenna, a meandering monopole antenna, a meandering dipole antenna, and a planar antenna, the area occupied by each antenna part in the antenna wiring is preferably 1000 ^mm2 or less, and the cured film is an insulating film that provides insulation between the ground and the antenna wiring.

Furthermore, the electronic component of the present invention is an electronic component including a semiconductor package having at least a semiconductor element, a redistribution layer, a sealing resin, and an antenna wiring, and it is preferable that the insulating layer of the redistribution layer and/or the sealing resin includes the cured film of the present invention, and that the sealing resin also functions as an insulating film that provides insulation between the ground and the antenna wiring.

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. First, the evaluation methods in each example and comparative example will be described. For the evaluation, a photosensitive resin composition before curing (hereinafter referred to as varnish) that had been previously filtered through a polytetrafluoroethylene filter (manufactured by Sumitomo Electric Industries, Ltd.) with an average pore size of 1 μm was used.

(1) Molecular Weight Measurement The weight average molecular weight (Mw) of component (A) was confirmed using a GPC (gel permeation chromatography) device Waters 2690-996 (manufactured by Nippon Waters Co., Ltd.). Measurement was performed using N-methyl-2-pyrrolidone (hereinafter referred to as NMP) as the developing solvent, and the weight average molecular weight (Mw) and dispersity (PDI=Mw/Mn) were calculated in terms of polystyrene.

(2) Pattern Processability (2)-1 Developability and Sensitivity The varnish was spin-coated onto a silicon wafer using a spin coater (1H-360S, manufactured by Mikasa Co., Ltd.), and then pre-baked for 3 minutes at 120° C. using a hot plate (SCW-636, manufactured by Dainippon Screen Mfg. Co., Ltd.) to produce a pre-baked film with a thickness of 11 μm. The obtained prebaked film was exposed to 1000 mJ/cm2 by contact using a parallel light mask aligner (hereinafter referred to as PLA) (Canon Inc. PLA-501F) with an ultra-high pressure mercury lamp as a light source (mixture of g, h, and i rays) through a grayscale mask for sensitivity measurement (having 1:1 line and space patterns of 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 8 μm, 10 μm, 12.5 μm, 15 μm, 20 μm, 25 μm, 30 μm, 40 μm, and 50 μm, respectively, with areas having transmittances of 1%, 5%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, ²⁵ %, 30%, 35%, 40%, 50%, and 60%). The film was then baked at 120°C for 3 minutes and developed using a coating and developing apparatus MARK-7. It was shower developed using cyclopentanone (CP) for 2 minutes and then rinsed with propylene glycol monomethyl ether acetate (PGMEA) for 30 seconds. If the development was excessive or insufficient, the development time and rinse time were adjusted appropriately.

After development, the film thickness was measured, and the minimum exposure amount at which the film thickness exceeded 95 when the film thickness of the 1000 mJ exposed area was taken as 100 was determined as the optimal exposure amount. In addition, the remaining film rate was measured by dividing the film thickness at the optimal exposure amount by the pre-baked film thickness. Sensitivity was evaluated as follows: A for those with a residual film thickness of 90% or more, B for 80% or more but less than 90%, C for 70% or more but less than 80%, D for 50% or more but less than 70%, and E for less than 50%. In addition, the exposure amount was measured with an I-line illuminometer. The film thickness was measured with a Lambda Ace STM-602 manufactured by Dainippon Screen Mfg. Co., Ltd., with a refractive index of 1.629. The same applies to the film thicknesses described below.

(2)-2 Resolution The minimum pattern dimension after development at the optimum exposure dose defined in (2)-1 was measured.

(3) Measurement of dielectric constant and dielectric tangent The varnish was applied to a 6-inch silicon wafer by spin coating using a coating and developing apparatus ACT-8 so that the film thickness after pre-baking at 120 ° C for 3 minutes was 11 μm, and then the entire surface was exposed to 300 mJ / cm ² using PLA, and the temperature was raised to 320 ° C at 3.5 ° C / min with an oxygen concentration of 20 ppm or less using an inert oven CLH-21CD-S (manufactured by Koyo Thermo Systems Co., Ltd.), and heat treatment was performed at each temperature for 1 hour. When the temperature reached 50 ° C or less, the silicon wafer was removed and immersed in 45 mass % hydrofluoric acid for 5 minutes to peel off the cured film of the resin composition from the wafer. The film was cut into a strip of 1.5 cm width and 3 cm length, and the dielectric constant and dielectric loss tangent at a frequency of 1 GHz were measured at room temperature of 23.0° C. and humidity of 45.0% RH by a perturbation type cavity resonator method in accordance with ASTM D2520. The dielectric properties were evaluated on a five-point scale as shown in Table 1 below.

(4) Measurement of elongation at break of cured film after curing A free-standing cured film was prepared in the same manner as in "(3) Measurement of dielectric constant and dielectric tangent" above, and this film was cut into strips 1.5 cm wide and 9 cm long. Using a Tensilon RTM-100 (manufactured by Orientec Co., Ltd.), the film was pulled at a room temperature of 23.0°C and a humidity of 45.0% RH at a tensile speed of 50 mm/min (chuck spacing = 2 cm) to measure the elongation at break (%). Measurements were performed on 10 strips per specimen, and the average of the top 5 highest values was calculated from the results (significant digits = 2 digits).

(5) Evaluation of elongation at break of cured film after high temperature storage (HTS) The varnish was applied to a 6-inch silicon wafer by spin coating using a coating and developing apparatus MARK-7 so that the film thickness after pre-baking at 120°C for 3 minutes was 11 μm, and then the entire surface was exposed to 300 mJ/ ^cm2 using PLA. Using an inert oven CLH-21CD-S (manufactured by Koyo Thermo Systems Co., Ltd.), the temperature was raised to 320°C at 3.5°C/min with an oxygen concentration of 20 ppm or less, and heat treatment was performed at 320°C for 1 hour. When the temperature reached 50°C or less, the wafer was removed, and then treated at 150°C for 250 hours using a high temperature storage tester. The wafer was removed, and a free-standing film of the cured film was prepared according to the procedure after the hydrofluoric acid treatment described above in "(3) Measurement of dielectric constant and dielectric tangent", and the elongation at break (%) was evaluated in the same manner as in "(4) Measurement of elongation at break of cured film after curing". Measurements were performed on 10 strips per specimen, and the average of the top 5 highest values was calculated from the results (significant digits = 2 digits).

Abbreviations for compounds used in the Synthesis Examples and Examples are listed below.
BPDA: 3,3',4,4'-biphenyl tetracarboxylic dianhydride ODPA: 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride 6FDA: 2,2-bis(2,3-dicarboxyphenyl)hexafluoropropane dianhydride BSAA: 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic) dianhydride HPMDA: 1,2,4,5-cyclohexane tetracarboxylic dianhydride DAE: 4,4'-diaminodiphenyl ether TFMB: 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl,
Priamine 1075: a dimer diamine compound containing the compound represented by the formula (4) (trade name, manufactured by Croda Japan Co., Ltd.) (average amine value: 205)
Versamine 551: a dimer diamine compound containing the compound represented by formula (5) (trade name, manufactured by BASF Corporation) (average amine value: 205)
6FAP: bis(3-amino-4-hydroxyphenyl)hexafluoropropane DACH: diaminocyclohexane MAP: m-aminophenol NCI-831: oxime ester photopolymerization initiator (trade name, manufactured by ADEKA Corporation)
IRGANOX3114: Hindered phenol-based antioxidant (product name, manufactured by BASF Ltd.)
4G: Tetraethylene glycol dimethacrylate (product name, manufactured by Shin-Nakamura Chemical Co., Ltd.)
DCP-A: Dicyclopentadiene dimethacrylate (product name, manufactured by Kyoeisha Chemical Co., Ltd.)
HEMA: 2-hydroxyethyl methacrylate OA: oleyl alcohol DMM: dimethylaminoethyl methacrylate NMP: N-methyl-2-pyrrolidone EL: ethyl lactate CP: cyclopentanone PGMEA: propylene glycol methyl ether acetate Polyflow 77: acrylic surfactant (trade name, manufactured by Kyoeisha Chemical Co., Ltd.)
Diamine A: a compound having the following structure

[Synthesis Example 1: Synthesis of polyimide precursor (P-1)]
31.02 g (0.10 mol) of ODPA was placed in a 500 ml separable flask, 26.03 g (0.20 mol) of HEMA and 123 ml of NMP were added, and 22.26 g (0.22 mol) of triethylamine was added with stirring at room temperature to obtain a reaction mixture. After the heat generation due to the reaction had ceased, the mixture was allowed to cool to room temperature and left to stand for 16 hours.

Next, the temperature was raised to 40°C, and 76.7 g (0.2 mol) of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate was added to the reaction mixture and stirred for 30 minutes. Next, a solution of 52.51 g (0.192 mol as amino groups) of Priamine 1075 dissolved in 130 mL of NMP was added dropwise over 10 minutes while stirring. After further stirring at room temperature for 2 hours, 0.87 g (0.008 mol) of MAP was added and stirred for 1 hour to obtain a reaction solution.

The resulting reaction solution was allowed to cool to room temperature, and 3 L of water was added to produce a precipitate consisting of a crude polymer. This precipitate was collected by filtration, washed three times with water, then washed twice with 500 mL of isopropyl alcohol, and vacuum dried to obtain a powdered polyimide precursor (P-1). The molecular weight of the polyimide precursor (P-1) was measured by gel permeation chromatography (standard polystyrene equivalent), and the weight average molecular weight (Mw) was 18,000 and the PDI was 2.4.

[Synthesis Examples 2 to 14, 16]
The polyimide precursors (P-2) to (P-14) and (P-16) were synthesized in the same manner as in Synthesis Example 1 using the molar ratios shown in Table 2 below.

[Synthesis Example 15: Synthesis of polyimide precursor (P-15)]
Under a dry nitrogen stream, 52.05 g (0.10 mol) of BSAA was dissolved in 250 g of NMP. 16.41 g of Priamine 1075 (0.06 mol as amino group) and 21.14 (0.066 mol) of TFMB were added together with 100 g of NMP, and the mixture was reacted at 20° C. for 1 hour, and then at 50° C. for 2 hours. Next, 0.87 g (0.08 mol) of 3-aminophenol was added as a terminal blocking agent together with 30 g of NMP, and the mixture was reacted at 50° C. for 2 hours. After that, the mixture was returned to room temperature, 31.44 g of DMM was added, and the mixture was stirred for 30 minutes to obtain a reaction solution. The mixture was further diluted with NMP until the solid concentration reached 25%, and a solution of polyimide precursor (P-15) was obtained. Since the molecular weight of the polyimide precursor (P-15) could not be measured accurately, the molecular weight of the polymer before the DMM reaction was measured by gel permeation chromatography (converted into standard polystyrene) to find that the Mw was 34,000 and the PDI was 2.8.

[Example 1]
Under yellow light, 10.00 g of polyimide precursor (P-1), 0.5 g of NCI-831, 0.10 g of IRGANOX3114, and 0.30 g of 3-trimethoxysilylphthalamic acid were dissolved in 15.15 g of NMP and 3.81 g of EL, and 0.10 g of a 1% by mass EL solution of Polyflow 77 was added and stirred to obtain a varnish. The properties of the obtained varnish were measured by the above-mentioned evaluation methods for pattern processability, dielectric constant, dielectric loss tangent, and elongation at break.

[Example 2]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-2.

[Example 3]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-3.

[Example 4]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-4.

[Example 5]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-5.

[Example 6]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-6.

[Example 7]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-7.

[Example 8]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-8.

[Example 9]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-9.

[Example 10]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-10.

[Example 11]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-11.

[Example 12]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-12.

[Example 13]
Under yellow light, 0.5 g of NCI-831, 0.10 g of IRGANOX3114, and 0.30 g of 3-trimethoxysilylphthalamic acid were dissolved in 40.00 g of the solution of polyimide precursor (P-13) synthesized in Synthesis Example 13. Next, 0.10 g of a 1 mass % EL solution of Polyflow 77 was added and stirred to obtain a varnish. The characteristics of the obtained varnish were measured by the above-mentioned evaluation method in terms of pattern processability, dielectric constant, dielectric dissipation factor, and elongation at break. However, a mixed solution of NMP/PGMEA/water = 8/1/1 (weight ratio) was used as the developer, and isopropyl alcohol was used as the rinse solution after development.

[Example 14]
The same procedure as in Example 1 was repeated, except that P-1 was replaced with P-9 and 0.2 g of 4G was further added.

[Example 15]
The same procedure as in Example 1 was repeated, except that P-1 was replaced with P-9 and 0.2 g of DCP-A was further added.

[Comparative Example 1]
The same procedure as in Example 1 was repeated except that P-1 was replaced with P-13.

The compositions and evaluation results of the examples and comparative examples are shown in Tables 3 and 4 below.

1 Silicon wafer 2 Al pad 3 Passivation film 4 Insulation film 5 Metal (Cr, Ti, etc.) film 6 Metal wiring (Al, Cu, etc.)
Reference Signs List 7 insulating film 8 barrier metal 9 scribe line 10 solder bump 31 antenna portion 32 matching circuit 33 MSL power supply line 34 power supply point 35 ground 36 insulating film J ground thickness K antenna wiring thickness M matching circuit length L antenna portion length W antenna portion width 401 IC chip 402 electrode pad 403 second via wiring 404 planar antenna wiring 405 second sealing resin 406 ground 407 first via wiring 408 first sealing resin 409 copper wiring 410 insulating film 411 barrier metal 412 solder bump

Claims (14)

A photosensitive resin composition comprising (A) a polyimide precursor and (B) a photopolymerization initiator, the polyimide precursor (A) comprising a resin having a structural unit represented by general formula (1):

(In general formula (1), ^X1 represents a tetravalent to hexavalent organic group, and ^Y1 represents a divalent to hexavalent organic group. However, at least one of ^X1 and ^Y1 has an alicyclic hydrocarbon structure having 4 to 8 carbon atoms which may have an unsaturated bond. In the alicyclic hydrocarbon structure, at least four hydrogen atoms are substituted with a hydrocarbon group having 4 to 12 carbon atoms which may have an unsaturated bond. Multiple ^R1s may be the same or different and represent a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom. However, not all ^R1s are hydrogen atoms. p represents an integer of 2 to 4. Multiple ^R2s may be the same or different and represent a carboxyl group, a hydroxyl group, or a monovalent organic group having an ethylenically unsaturated bond. q represents an integer of 0 to 4. * represents a bonding point.) 2. The photosensitive resin composition according to claim 1, wherein, in the general formula (1), ^Y1 is a residue of a polyamine represented by the general formula (2).

(In the general formula (2), m represents an integer of 4 to 8. Each W independently represents a structural unit represented by the general formula (2a), (2b) or (2c). Of the m Ws, two or more structural units of (2c) are contained, and the sum of the numbers of (2b) and (2c) is 4 or more and 8 or less. Each n and o independently represents an integer of 3 to 11.) 3. The photosensitive resin composition according to claim 1, wherein, in the general formula (1), Y ¹ is a residue of a diamine represented by formula (4).

4. The photosensitive resin composition according to claim 1, wherein in the general formula (1), R ¹ is a residue of an unsaturated fatty acid modified alcohol. 5. The photosensitive resin composition according to claim 1, wherein the polyimide precursor (A) contains a resin having structural units represented by the general formulas (1) and (7).

(In the general formula (7), ^X2 represents a tetravalent to hexavalent organic group, and ^Y2 represents a divalent to hexavalent organic group, provided that at least ^X2 is ^X3 or ^Y2 is ^Y3 . ^X3 is selected from a divalent to hexavalent organic group containing at least one of a bisphenol A skeleton, a biphenyl skeleton, and a hexafluoroisopropylidene skeleton, or a residue of an acid anhydride represented by the following general formula (8). Y3 is selected from a divalent to hexavalent organic group containing at least one of a bisphenol A skeleton, a biphenyl skeleton, and a hexafluoroisopropylidene skeleton, or a residue of a diamine represented by the following formula (9). A plurality of ^R3s may be the same or different and represent a monovalent organic group having an ethylenically unsaturated bond or a hydrogen atom, provided that not all R3s are hydrogen atoms. r represents an integer of 2 to 4. A plurality of ^R3s may be selected from a divalent to hexavalent organic group containing at least one of a bisphenol A skeleton, a biphenyl skeleton, and a ^{hexafluoroisopropylidene} skeleton, or a residue of a diamine represented by the following formula (9). ⁴ may be the same or different and represents a monovalent organic group having a carboxyl group, a hydroxyl group, or an ethylenically unsaturated bond. s represents an integer of 0 to 4. * represents a bonding point.)

(In the general formula (8), a represents an integer of 6 to 20. * represents a bonding point.)

(In the general formula (9), * indicates a bonding point.) The photosensitive resin composition according to any one of claims 1 to 5 , further comprising (C) a compound having two or more ethylenically unsaturated bonds, the component (C) having a molecular weight of 100 or more and 2000 or less. The photosensitive resin composition according to claim 6 , wherein the component (C) is a compound having an alicyclic structure. A photosensitive sheet formed from the photosensitive resin composition according to any one of claims 1 to 7 . A cured film obtained by curing the photosensitive resin composition according to any one of claims 1 to 7 or the photosensitive sheet according to claim 8 . A method for producing a cured film using the photosensitive resin composition according to any one of claims 1 to 7 or the photosensitive sheet according to claim 8 , comprising the steps of:
A method for producing a cured film, comprising the steps of applying the photosensitive resin composition onto a substrate or laminating the photosensitive sheet onto a substrate and drying to form a photosensitive resin film, exposing the photosensitive resin film to light, developing the exposed photosensitive resin film, and heat-treating the developed photosensitive resin film. An interlayer insulating film having the cured film according to claim 9 disposed thereon. An electronic component having the cured film according to claim 9 . 13. An electronic component comprising at least one or more antenna wirings and an antenna element having the cured film according to claim 9 , wherein the antenna wiring comprises one or more antennas selected from the group consisting of a meandering loop antenna, a coiled loop antenna, a meandering monopole antenna, a meandering dipole antenna, and a planar antenna, the area occupied by each antenna part in the antenna wiring is 1000 ^mm2 or less, and the cured film is an insulating film that insulates between a ground and the antenna wiring. 14. The electronic component according to claim 12 or 13, comprising a semiconductor package having at least a semiconductor element, a redistribution layer, a sealing resin, and an antenna wiring, wherein an insulating layer of the redistribution layer and/or the sealing resin comprises the cured film according to claim 9 , and the sealing resin also functions as an insulating film for insulating between a ground and the antenna wiring.

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