JP7476574B2 - Resin composition, carrier-attached resin film, prepreg, laminate, printed wiring board, and semiconductor device using the same - Google Patents

Description

The present invention relates to a resin composition, a resin film with a carrier, a prepreg, a laminate, a printed wiring board, and a semiconductor device that use the resin composition.

Various developments have been made in resin compositions for use in circuit boards. One such technology is described in Patent Document 1. Patent Document 1 discloses a resin composition that uses polyphenylene ether, epoxy resin, and inorganic filler in order to obtain excellent dielectric properties.

JP 2014-240474 A

However, as a result of the inventor's investigations, it was found that there is room for improvement in the resin composition described in Patent Document 1 in terms of the properties of low dielectric tangent and good laser processability.

After further investigation, the inventors unexpectedly discovered that by creating a resin composition containing a new combination of modified polyphenylene ether, a maleimide compound, and an indene resin, it was possible to reduce the dielectric tangent of a resin film (cured product) made from the resin composition while improving the laser processability of the resin film, and thus completed the present invention.

According to the present invention, there is provided a resin composition comprising the following components (A) to (C):
(A) a modified polyphenylene ether in which a phenolic hydroxyl group at a molecular end of a polyphenylene ether is modified with a compound having a carbon-carbon unsaturated double bond, the modified polyphenylene ether being contained in an amount of 1 part by weight or more and 30 parts by weight or less relative to 100 parts by weight of the resin solid content of the resin composition; (B) a maleimide compound being contained in an amount of 5 parts by weight or more and 40 parts by weight or less relative to 100 parts by weight of the resin solid content of the resin composition; (C) an indene resin being contained in an amount of 1 part by weight or more and 20 parts by weight or less relative to 100 parts by weight of the resin solid content of the resin composition.

The present invention also provides a cured product of the above resin composition.

The present invention also provides a prepreg containing a fiber base material in the resin composition.

The present invention also provides a laminate having a metal layer disposed on at least one surface of the prepreg.

The present invention also provides a resin film with a carrier, comprising a carrier substrate and a resin film made of the resin composition provided on the carrier substrate.

The present invention also provides a printed wiring board having an insulating layer made of the cured product of the above-mentioned resin composition.

Further, according to the present invention,
The printed wiring board;
and a semiconductor element mounted on a circuit layer of the printed wiring board or embedded in the printed wiring board.

The present invention provides a resin composition that combines low dielectric tangent and good laser processability, and a resin film with a carrier, a prepreg, a laminate, a printed wiring board, and a semiconductor device that use the resin composition.

FIG. 1 is a diagram illustrating an example of a configuration of a substrate-attached resin sheet according to an embodiment of the present invention. 1A to 1C are cross-sectional views showing an example of a manufacturing process for the semiconductor device according to the embodiment.

The following describes an embodiment of the present invention with reference to the drawings. In all drawings, similar components are given similar reference symbols and descriptions are omitted where appropriate. The drawings are schematic and do not correspond to the actual dimensional ratios. In this specification, "~" indicates that the upper and lower limits are included unless otherwise specified.

<Resin Composition>
The resin composition of the present embodiment contains the following components (A) to (C).
(A) Modified polyphenylene ether (B) Maleimide compound (C) Indene resin

According to the inventors' findings, the combination of components (A) to (C) can achieve both a low dielectric tangent and good laser processability.

The dielectric loss tangent at 10 GHz of the cured product of the resin composition of this embodiment is preferably 0.006 or less, more preferably 0.005 or less, and even more preferably 0.004 or less. The lower limit of the dielectric loss tangent is not particularly limited, but may be, for example, 1.0×10 ⁻³ or more.
The term "cured product" refers to a product obtained by heating and curing the resin composition of the present embodiment at 225°C for two hours.

The dielectric tangent can be controlled by, for example, appropriately selecting the type and amount of each component contained in the resin composition, the method for preparing the resin composition, etc.

The components contained in the resin composition of this embodiment are described in detail below.

(A) Modified polyphenylene ether The (A) modified polyphenylene ether of the present embodiment is a modified polyphenylene ether, and for example, those described in paragraphs 0018 to 0061 of WO 2014/203511 can be used. More specifically, they are as follows.

The modified polyphenylene ether (A) according to this embodiment is not particularly limited, but is preferably a modified polyphenylene ether whose terminals are modified with a substituent having a carbon-carbon unsaturated bond.
The substituent having a carbon-carbon unsaturated bond is not particularly limited, but examples thereof include the substituents represented by the following formula (1).

In the above formula (1), n is an integer from 0 to 10, Z is an arylene group, and R1 to R3 are each independently a hydrogen atom or an alkyl group.

In the above formula (1), when n = 0, Z is directly bonded to the end of the polyphenylene ether. In addition, examples of the arylene group of Z include monocyclic aromatic groups such as a phenylene group and polycyclic aromatic groups such as a naphthalene ring, and also include derivatives in which the hydrogen atom bonded to the aromatic ring is replaced with a functional group such as an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group.

The functional group shown in the above formula (1) may be, for example, a functional group containing a vinylbenzyl group. More specifically, it may be at least one substituent selected from the following formula (2) or formula (3).

Another example of a substituent having a carbon-carbon unsaturated bond directly bonded to the end of the polyphenylene ether is a (meth)acrylate group represented by the following formula (4).

上記式（４）中、Ｒ４は水素原子またはアルキル基を示す。

In the above formula (4), R4 represents a hydrogen atom or an alkyl group.

In order to achieve both low dielectric properties and good laser processability, it is preferable that the modified polyphenylene ether of this embodiment has hydroxyl groups or methacrylic groups at both ends.

In addition, the polyphenylene ether in the modified polyphenylene ether of this embodiment has a polyphenylene ether chain in the molecule, and preferably has, for example, a repeating unit represented by the following formula (5) in the molecule.

In the above formula (5), m represents 1 to 50. R5, R6, R7, and R8 are each independent and may be the same group or different groups. R5, R6, R7, and R8 represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a formyl group, an alkylcarbonyl group, an alkenylcarbonyl group, or an alkynylcarbonyl group. Among these, a hydrogen atom and an alkyl group are preferred.

The alkyl group is not particularly limited, but is preferably an alkyl group having 1 to 18 carbon atoms, and more preferably an alkyl group having 1 to 10 carbon atoms. More specific examples include a methyl group, an ethyl group, a propyl group, a hexyl group, and a decyl group.
The alkenyl group is not particularly limited, but for example, an alkenyl group having 2 to 18 carbon atoms is preferable, and an alkenyl group having 2 to 10 carbon atoms is more preferable. More specific examples include a vinyl group, an allyl group, and a 3-butenyl group.
The alkynyl group is not particularly limited, but for example, an alkynyl group having 2 to 18 carbon atoms is preferable, and an alkynyl group having 2 to 10 carbon atoms is more preferable. More specific examples include an ethynyl group, a prop-2-yn-1-yl group (propargyl group), and the like.

The alkylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkyl group, but for example, an alkylcarbonyl group having 2 to 18 carbon atoms is preferable, and an alkylcarbonyl group having 2 to 10 carbon atoms is more preferable. More specific examples include an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a pivaloyl group, a hexanoyl group, an octanoyl group, and a cyclohexylcarbonyl group.
The alkenylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkenyl group, but for example, an alkenylcarbonyl group having 3 to 18 carbon atoms is preferable, and an alkenylcarbonyl group having 3 to 10 carbon atoms is more preferable. More specific examples include an acryloyl group, a methacryloyl group, and a crotonoyl group.
The alkynylcarbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkynyl group, but for example, an alkynylcarbonyl group having 3 to 18 carbon atoms is preferable, and an alkynylcarbonyl group having 3 to 10 carbon atoms is more preferable. More specific examples include a propioloyl group.

The method for synthesizing the modified polyphenylene ether according to this embodiment is not particularly limited as long as it is possible to synthesize a modified polyphenylene ether whose terminals are modified with a substituent having a carbon-carbon unsaturated bond. For example, a method of reacting a polyphenylene ether in which the hydrogen atoms of the terminal phenolic hydroxyl groups are replaced with alkali metal atoms such as sodium or potassium with a compound represented by the following formula (6) can be mentioned.

In the above formula (6), as in the above formula (1), n represents an integer of 0 to 10, Z represents an arylene group, and R1 to R3 each independently represent a hydrogen atom or an alkyl group. Furthermore, X represents a halogen atom, specific examples of which include a chlorine atom, a bromine atom, an iodine atom, and a fluorine atom. Among these, a chlorine atom is preferred.

The compound represented by the above formula (6) is not particularly limited, but is preferably, for example, p-chloromethylstyrene or m-chloromethylstyrene.

In addition, the compounds represented by formula (6) may be used alone or in combination of two or more of the above-mentioned examples.

The raw material polyphenylene ether is not particularly limited as long as it can ultimately synthesize a desired modified polyphenylene ether. Specific examples include polyarylene ether copolymers consisting of 2,6-dimethylphenol and at least one of a difunctional phenol and a trifunctional phenol, and those mainly composed of polyphenylene ether such as poly(2,6-dimethyl-1,4-phenylene oxide). More specific examples of such polyphenylene ethers include polyphenylene ethers having the structure shown in the following formula (7).

In the above formula (7), it is preferable that the sum of s and t is, for example, 1 to 30. It is also preferable that s is 0 to 20, and t is 0 to 20. In other words, it is preferable that s is 0 to 20, t is 0 to 20, and the sum of s and t is 1 to 30.

Commercially available modified polyphenylene ethers in which the terminal hydroxyl groups of the polyphenylene ether of formula (7) above have been modified with methacrylic groups include "SA9000" manufactured by SABIC Innovative Plastics.

The weight average molecular weight of component (A) is preferably 500 or more and 5,000 or less, more preferably 800 or more and 4,000 or less, and even more preferably 1,000 or more and 3,000 or less. The weight average molecular weight may be measured by a general molecular weight measurement method, and specifically, a value measured using gel permeation chromatography (GPC) may be mentioned.

By making the weight average molecular weight of component (A) equal to or greater than the lower limit, the excellent dielectric properties of polyphenylene ether are exhibited, and the cured product thereof further exhibits excellent adhesion and heat resistance. Since component (A) of this embodiment is modified and has terminal reactive groups, particularly terminal unsaturated double bonds, it is believed that the cured product has an improved glass transition temperature while maintaining low dielectric properties, good laser processability, and sufficiently high heat resistance and adhesion.
On the other hand, by adjusting the weight average molecular weight of component (A) to be equal to or less than the above upper limit, the moldability, solvent solubility and storage stability become good.

The content of component (A) is preferably 1 part by weight or more and 30 parts by weight or less relative to 100 parts by weight of resin solids. By making it 1 part by weight or more relative to 100 parts by weight of resin solids, a low dielectric tangent due to component (A) can be obtained, and by making it 30 parts by weight or less, resin residue can be suppressed and good laser processability can be obtained. The content of component (A) is more preferably 3 parts by weight or more, and even more preferably 5 parts by weight or more, and more preferably 25 parts by weight or less, and even more preferably 20 parts by weight or less relative to 100 parts by weight of resin solids.
The resin solid content refers to the resin components in the varnish excluding the filler and the solvent.

(B) Maleimide Compound The maleimide group of the maleimide compound has a planar structure of a five-membered ring, and the double bond of the maleimide group is highly polar and easily interacts with molecules, so that it exhibits strong intermolecular interactions with the maleimide group, benzene ring, other compounds having a planar structure, etc., and can suppress molecular motion. Therefore, by including the maleimide compound in the resin composition of the present embodiment, the linear expansion coefficient of the obtained insulating layer can be reduced, the glass transition temperature can be improved, and further, the heat resistance can be improved.

The maleimide compound is preferably a maleimide compound having at least two maleimide groups in the molecule.
Examples of maleimide compounds having at least two maleimide groups in the molecule include compounds having two maleimide groups in the molecule, such as 4,4'-diphenylmethane bismaleimide, m-phenylene bismaleimide, p-phenylene bismaleimide, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane, 4-methyl-1,3-phenylene bismaleimide, N,N'-ethylene dimaleimide, N,N'-hexamethylene dimaleimide, bis(4-maleimidophenyl)ether, bis(4-maleimidophenyl)sulfone, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane bismaleimide, and bisphenol A diphenyl ether bismaleimide; and compounds having three or more maleimide groups in the molecule, such as polyphenylmethane maleimide.
Among these, one type may be used alone, or two or more types may be used in combination. Among these maleimide compounds, 4,4'-diphenylmethane bismaleimide, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane, polyphenylmethane maleimide, and bisphenol A diphenyl ether bismaleimide are preferred because of their low water absorption.

The content of component (B) is preferably 5 parts by weight or more and 40 parts by weight or less, more preferably 8 parts by weight or more and 35 parts by weight or less, and even more preferably 10 parts by weight or more and 30 parts by weight or less, based on 100 parts by weight of the resin solid content.
By making the content of component (B) equal to or greater than the lower limit, it is possible to obtain good dielectric tangent and laser processability while lowering the linear expansion coefficient, increasing the glass transition temperature, and improving heat resistance. On the other hand, by making the content of component (B) equal to or less than the upper limit, it is possible to improve the balance between good dielectric tangent and laser processability.

(C) Indene Resin In this embodiment, the indene resin refers to a (co)polymer containing an indene residue in its skeletal structure and having an average degree of polymerization of 4 to 8, and may be a copolymer of indene (C ₉ H ₈ ) with coumarone (1-benzofuran), styrene (C ₈ H ₈ ), α-methylstyrene, methylindene, and vinyltoluene. Among these, an indene-coumarone copolymer, an indene-styrene copolymer, or an indene-coumarone-styrene copolymer is preferable.

That is, the indene resin contains a structural unit A derived from an indene monomer, and may have structural units derived from other monomers. Examples of structural units derived from other monomers include a structural unit B derived from a coumarone monomer and a structural unit C derived from a styrene monomer. Specifically, the indene resin may have a structural unit A derived from an indene monomer, a structural unit B derived from a coumarone monomer, and a structural unit C derived from a styrene monomer, a structural unit A derived from an indene monomer and a structural unit B derived from a coumarone monomer, or a structural unit A derived from an indene monomer and a structural unit C derived from a styrene monomer. The indene resin may have a repeating structure of these structural units.

The structural unit A derived from the indene monomer is, for example, one represented by the following general formula (M1):

(In general formula (M1), R ¹ to R ⁷ are each independently a hydrogen atom or an organic group having 1 to 3 carbon atoms.)

The structural unit B derived from the coumarone monomer is, for example, one represented by the following general formula (M2):

(In general formula (M2), R ^C represents a hydrogen atom or an organic group having 1 to 3 carbon atoms. R ^C may be the same as or different from each other.)

Examples of the structural unit C derived from the styrene-based monomer include those represented by the following general formula (M3).

(In general formula (M3), R ^{1 S} is a hydrogen atom or an organic group having 1 to 3 carbon atoms. R ^{1 S} may be the same as or different from each other.)

In the above general formulas (M1) to (M3), R1 to R7, R C and R S may contain atoms other than hydrogen and carbon in the structure of the organic group, for example.
Specific examples of the atoms other than hydrogen and carbon include oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, fluorine atoms, chlorine atoms, etc. The atoms other than hydrogen and carbon may include one or more of the above specific examples.

In the above general formulas (M1) to (M3), R1 to R7, RC, and RS are each independently, for example, hydrogen or an organic group having 1 to 3 carbon atoms, preferably hydrogen or an organic group having 1 carbon atom, and more preferably hydrogen.

In the above general formulas (M1) to (M3), examples of the organic groups constituting R1 to R7, RC, and RS include alkyl groups such as methyl, ethyl, and n-propyl groups; alkenyl groups such as allyl and vinyl groups; alkynyl groups such as ethynyl groups; alkylidene groups such as methylidene and ethylidene groups; cycloalkyl groups such as cyclopropyl groups; and heterocyclic groups such as epoxy and oxetanyl groups.

The above-mentioned indene resin may contain, among others, a copolymer of indene, coumarone and styrene, or a copolymer of indene and styrene. This can improve the low dielectric properties.

Furthermore, the indene resin can have a reactive group in the molecule that reacts with the epoxy group of the epoxy resin, thereby improving the low dielectric properties.
Examples of the reactive group include an OH group and a COOH group.
The indene resin may have an aromatic structure having a phenolic hydroxyl group inside or at a terminal thereof.

The upper limit of the weight average molecular weight Mw of the indene resin is, for example, preferably 4000 or less, more preferably 2000 or less, even more preferably 1500 or less, and even more preferably 1200 or less. This improves the compatibility between the indene resin and the epoxy resin, and allows the indene resin to be properly dispersed. On the other hand, the lower limit of the weight average molecular weight Mw of the indene resin is, for example, preferably 400 or more, more preferably 500 or more, even more preferably 550 or more, and even more preferably 600 or more. This allows the indene resin to be properly dispersed in the resin composition.

The lower limit of the content of the indene resin is, for example, 1 part by weight or more, preferably 3 parts by weight or more, and more preferably 5 parts by weight or more, based on 100 parts by weight of the resin solid content. This makes it possible to improve the low water absorption property while obtaining a good balance between low dielectric properties and laser processability. On the other hand, the upper limit of the content of the indene resin is, for example, 20 parts by weight or less, preferably 15 parts by weight or less, and more preferably 12 parts by weight or less, based on the entire resin composition of this embodiment. This makes it possible to achieve a balance with other physical properties such as moldability and heat resistance.

The melting point of indene resin is preferably 40°C to 120°C, and the melting point can be controlled by the molecular weight and degree of polymerization.

The content of component (C) is preferably 0.1 parts by weight or more and 20 parts by weight or less, more preferably 0.5 parts by weight or more and 15 parts by weight or less, and even more preferably 1 part by weight or more and 12 parts by weight or less, based on 100 parts by weight of the resin solids.

The resin composition of this embodiment further contains the following components, which allows it to stably obtain low dielectric properties and good laser processability while improving other physical properties.

(D) Polybutadiene-based elastomer In this embodiment, the polybutadiene-based elastomer is a homopolymer or copolymer using a butadiene compound as a monomer component. In this embodiment, from the viewpoint of improving heat resistance, it is more preferable to use a polybutadiene-based elastomer having a functional group. Examples of the functional group include a vinyl group, an epoxy group, a carboxy group, a hydroxyl group, and a maleic acid group. Among them, from the viewpoint of improving compatibility and adhesion, a polybutadiene having a vinyl group in a side chain is preferable.
The copolymer has a segment skeleton formed by polymerization of butadiene in the resin, and examples thereof include styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylate butadiene copolymer, vinylpyridine butadiene copolymer, acrylonitrile-styrene-butadiene copolymer, carboxylated butadiene copolymer, epoxidized butadiene copolymer, etc. Among them, butadiene homopolymer and styrene-butadiene copolymer are preferable from the viewpoint of improving dispersibility and heat resistance.

The weight ratio (B/D) of component (B) to component (D) is preferably 0.5 to 8, and more preferably 2 to 6. By keeping the weight ratio (B/D) in this range, heat resistance can be improved.

The content of component (D) is preferably 0.1 parts by weight or more and 20 parts by weight or less, more preferably 0.2 parts by weight or more and 15 parts by weight or less, and even more preferably 0.5 parts by weight or more and 12 parts by weight or less, based on 100 parts by weight of the resin solids.

(E) Phenol having an unsaturated double bond In this embodiment, phenol having an unsaturated double bond is mainly used from the viewpoint of maintaining a balance between other physical properties while improving dielectric properties and laser processability. Phenol having an unsaturated double bond refers to a phenol having a phenol skeleton and having an unsaturated double bond in a substituent of a benzene ring.
In this embodiment, examples of the phenol having an unsaturated double bond include allylphenol (o-, m- or p-), vinylphenol (o-, m- or p-), allyl resorcinol, diallyl resorcinol, allyl catechol, diallyl catechol, allyl hydroquinone, diallyl hydroquinone, allyl pyrogallol, triallyl phenol, trivinyl phenol, triallyl resorcinol, trivinyl resorcinol, etc. Among these, from the viewpoint of improving adhesion, vinylphenol (particularly p-vinylphenol; 4-ethenylphenol), 2,2'-diallyl bisphenol A, o-allyl phenol (2-allyl phenol), and allyl phenol resorcinol type novolak resin are preferred.

The content of component (E) is preferably 1 part by weight or more and 30 parts by weight or less, more preferably 5 parts by weight or more and 25 parts by weight or less, and even more preferably 7 parts by weight or more and 22 parts by weight or less, based on 100 parts by weight of the resin solids.

(F) Polyfunctional Vinyl Compound In the present embodiment, (F) polyfunctional vinyl compound refers to a compound having two or more polymerizable unsaturated bonds in the molecule.
Examples of polyfunctional vinyl compounds include bifunctional aromatic vinyl compounds such as divinylbenzene and divinyltoluene; bifunctional (meth)acrylic acid esters such as 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, neopentyl glycol acrylate, allyl acrylate, neopentyl glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, 3-methylpentanediol diacrylate, and allyl methacrylate; trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, and the like. Examples of the (meth)acrylic acid esters include trifunctional or higher functional (meth)acrylic acid esters such as acrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, pentaerythritol pentaacrylate, pentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, and dipentaerythritol hexamethacrylate; (meth)acrylic acid esters of polyhydric alcohols such as (poly)ethylene glycol dimethacrylate; diallyl maleate, diallyl fumarate, triallyl cyanurate, triallyl isocyanate, diallyl phthalate, and bis(acryloyloxyethyl) ether of bisphenol A, which may be used alone or in combination of two or more.
Of these, (meth)acrylic acid esters of polyhydric alcohols such as (poly)ethylene glycol dimethacrylate; diallyl maleate, diallyl fumarate, triallyl cyanurate, triallyl isocyanate, diallyl phthalate, and bis(acryloyloxyethyl) ether of bisphenol A are preferred, with triallyl isocyanate being more preferred.

The content of component (F) is preferably 0.5 parts by weight or more and 30 parts by weight or less, more preferably 1 part by weight or more and 20 parts by weight or less, and even more preferably 4 parts by weight or more and 15 parts by weight or less, based on 100 parts by weight of the resin solids.

(G) Inorganic Filler In this embodiment, examples of the inorganic filler (G) include silicates such as talc, calcined clay, uncalcined clay, mica, and glass; oxides such as titanium oxide, alumina, boehmite, silica, and fused silica; carbonates such as calcium carbonate, magnesium carbonate, and hydrotalcite; hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide; sulfates or sulfites such as barium sulfate, calcium sulfate, and calcium sulfite; borates such as zinc borate, barium metaborate, aluminum borate, calcium borate, and sodium borate; nitrides such as aluminum nitride, boron nitride, silicon nitride, and carbon nitride; and titanates such as strontium titanate and barium titanate.
Among these, talc, alumina, glass, silica, mica, aluminum hydroxide, and magnesium hydroxide are preferred, and silica is particularly preferred. As the inorganic filler, one of these may be used alone, or two or more of them may be used in combination.

The lower limit of the average particle diameter of the inorganic filler is not particularly limited, but may be, for example, 0.01 μm or more, or 0.05 μm or more. This can prevent the viscosity of the thermosetting resin varnish from increasing, and improve the workability when preparing the insulating layer. In addition, the upper limit of the average particle diameter of the inorganic filler is not particularly limited, but is preferably, for example, 5.0 μm or less, more preferably 2.0 μm or less, and even more preferably 1.0 μm or less. This can prevent the phenomenon of settling of the inorganic filler in the thermosetting resin varnish, and a more uniform resin film can be obtained. In addition, when the circuit dimension L/S of the printed wiring board is less than 20 μm/20 μm, the effect on the insulation between the wiring can be suppressed.

In this embodiment, the average particle diameter of the inorganic filler can be determined by measuring the particle size distribution of the particles on a volume basis using, for example, a laser diffraction particle size distribution measuring device (LA-500, manufactured by HORIBA), and taking the median diameter (D50) as the average particle diameter.

The inorganic filler is not particularly limited, but may be an inorganic filler having a monodisperse average particle size, or an inorganic filler having a polydisperse average particle size. Furthermore, one or more types of inorganic fillers having monodisperse and/or polydisperse average particle sizes may be used in combination.

The inorganic filler preferably contains silica particles. The silica particles may be spherical. The average particle size of the silica particles is not particularly limited, but may be, for example, 5.0 μm or less, 0.1 μm or more and 4.0 μm or less, or 0.2 μm or more and 2.0 μm or less. This can further improve the filling property of the inorganic filler.

The lower limit of the content of the inorganic filler is not particularly limited, but is preferably 40 parts by mass or more, more preferably 45 parts by mass or more, and even more preferably 50 parts by mass or more, based on 100 parts by mass of the total solid content of the resin composition. This allows the cured resin film to have particularly low thermal expansion and low water absorption. In addition, warping of the semiconductor package can be suppressed. On the other hand, the upper limit of the content of the inorganic filler is not particularly limited, but may be, for example, 85 parts by mass or less, 80 parts by mass or less, or 75 parts by mass or less, based on 100 parts by mass of the total solid content of the resin composition. This improves handling properties and makes it easier to form the resin film.

(H) Flame Retardant In this embodiment, examples of the (H) flame retardant include halogen-based flame retardants such as bromine-based flame retardants and phosphorus-based flame retardants. Specific examples of the halogen-based flame retardants include bromine-based flame retardants such as pentabromodiphenyl ether, octabromodiphenyl ether, decabromodiphenyl ether, tetrabromobisphenol A, and hexabromocyclododecane, and chlorine-based flame retardants such as chlorinated paraffin. Specific examples of the phosphorus-based flame retardants include phosphate esters such as condensed phosphate esters and cyclic phosphate esters, phosphazene compounds such as cyclic phosphazene compounds, phosphinate-based flame retardants such as phosphinic acid metal salts such as dialkylphosphinic acid aluminum salts, melamine phosphate, and melamine polyphosphate. As the flame retardant, each of the exemplified flame retardants may be used alone or in combination of two or more.
Among these, phosphorus-based flame retardants are preferred.

The content of component (H) is preferably 0.1 parts by weight or more and 15 parts by weight or less, more preferably 0.5 parts by weight or more and 10 parts by weight or less, and even more preferably 1 part by weight or more and 5 parts by weight or less, based on 100 parts by weight of the resin solids.

(Polymerization initiator)
The resin composition of the present embodiment may contain a polymerization initiator. This allows the component (A) to stably cure regardless of the process conditions. The polymerization initiator is not particularly limited as long as it can accelerate the curing reaction between the modified polyphenylene ether and the thermosetting curing agent, and examples thereof include oxidizing agents such as α,α'-bis(t-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, benzoyl peroxide, 3,3',5,5'-tetramethyl-1,4-diphenoquinone, chloranil, 2,4,6-tri-t-butylphenoxyl, t-butylperoxyisopropyl monocarbonate, and azobisisobutyronitrile. These may be used alone or in combination of two or more. In addition, from the viewpoint of further accelerating the curing reaction, a metal carboxylate or the like may be used in combination.
Among these, α,α'-bis(t-butylperoxy-m-isopropyl)benzene is preferably used. α,α'-bis(t-butylperoxy-m-isopropyl)benzene has a relatively high reaction initiation temperature, and therefore can suppress the promotion of the curing reaction at a time when curing is not required, such as when drying the prepreg, and can suppress a decrease in the storage stability of the resin composition of this embodiment. Furthermore, α,α'-bis(t-butylperoxy-m-isopropyl)benzene has low volatility, so it does not volatilize during drying or storage of the prepreg, and good stability can be obtained.

(Coupling Agent)
The resin composition of the present embodiment may contain a coupling agent. The coupling agent may be added directly when preparing the resin composition, or may be added to the inorganic filler in advance. The use of the coupling agent can improve the wettability of the interface between the inorganic filler and each resin. Therefore, it is preferable to use a coupling agent, and the heat resistance of the cured resin film can be improved. In addition, the use of the coupling agent can improve the adhesion to the copper foil. Furthermore, since the moisture absorption resistance can be improved, the adhesion to the copper foil can be maintained even in a humid environment.

The above-mentioned coupling agent may be, for example, a silane coupling agent such as a vinyl-based silane coupling agent, an epoxy silane coupling agent, a cationic silane coupling agent, or an amino silane coupling agent, a titanate-based coupling agent, or a silicone oil-type coupling agent. The coupling agent may be used alone or in combination of two or more kinds. In this embodiment, the coupling agent may contain a silane coupling agent.
This makes it possible to increase the wettability at the interface between the inorganic filler and each resin, and further improve the heat resistance of the cured resin film.

Various types of silane coupling agents can be used, including, for example, epoxy silane, amino silane, alkyl silane, ureido silane, mercapto silane, vinyl silane, etc.

Specific compounds include, for example, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-phenylγ-aminopropyltriethoxysilane, N-phenylγ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, N-6-(aminohexyl)3-aminopropyltrimethoxysilane, N-(3-(trimethoxysilylpropyl)-1,3-benzenedimethanane, γ-glycidoxypropanol, Examples of the silane include vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, γ-ureidopropyltriethoxysilane, vinyltriethoxysilane, etc., and one or more of these can be used in combination. Among these, vinylsilane, epoxysilane, mercaptosilane, and aminosilane are preferred, and as the aminosilane, primary aminosilane or anilinosilane is more preferred.

The content of the coupling agent can be appropriately adjusted based on the specific surface area of the inorganic filler. The lower limit of the content of such a coupling agent may be, for example, 0.01 parts by weight or more, preferably 0.05 parts by weight or more, based on 100 parts by weight of the total solid content of the resin composition. When the content of the coupling agent is equal to or more than the lower limit, the inorganic filler can be sufficiently coated, and the heat resistance of the cured resin film can be improved. On the other hand, the upper limit of the content of the coupling agent may be, for example, 3 parts by weight or less, preferably 1.5 parts by weight or less, based on 100 parts by weight of the total solid content of the resin composition. When the content of the coupling agent is equal to or less than the upper limit, the effect on the reaction can be suppressed, and the decrease in the bending strength of the cured resin film can be suppressed.

(Others, additives)
The resin composition of the present embodiment may contain additives other than the above-mentioned components, such as resins other than those mentioned above, dyes such as green, red, blue, yellow, and black, pigments such as black pigments, colorants including one or more selected from the group consisting of dyes, stress reducing agents, antifoaming agents, leveling agents, ultraviolet absorbing agents, foaming agents, antioxidants, ion trapping agents, rubber components, etc., within the scope of the present invention. These may be used alone or in combination of two or more.
Examples of resins other than those mentioned above include thermosetting resins such as epoxy resins and benzocyclobutene resins, thermoplastic resins, phenoxy resins, and cyanate resins.

(varnish)
In this embodiment, the varnish-like resin composition may contain a solvent.
Examples of the solvent include organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, toluene, ethyl acetate, cyclohexane, heptane, cyclohexane, cyclohexanone, tetrahydrofuran, dimethylformamide, dimethylacetamide, dimethylsulfoxide, ethylene glycol, cellosolve-based solvents, carbitol-based solvents, anisole, and N-methylpyrrolidone. These may be used alone or in combination of two or more kinds.

When the resin composition is in the form of a varnish, the solid content of the resin composition may be, for example, 30% by mass or more and 80% by mass or less, and more preferably 40% by mass or more and 70% by mass or less. This results in a resin composition with excellent workability and film-forming properties.

The varnish-like resin composition can be prepared by dissolving, mixing, and stirring the above-mentioned components in a solvent using various mixers, such as those using ultrasonic dispersion, high-pressure collision dispersion, high-speed rotation dispersion, bead mill, high-speed shear dispersion, and rotation-revolution dispersion.

<Resin film>
Next, the resin film of this embodiment will be described.
The resin film of this embodiment can be obtained by forming the above-mentioned resin composition in a varnish state into a film. For example, the resin film of this embodiment can be obtained by removing the solvent from a coating film obtained by applying the resin composition in a varnish state. In such a resin film, the solvent content can be 5 mass% or less with respect to the entire resin film. In this embodiment, for example, a step of removing the solvent may be performed under conditions of 100°C to 150°C and 1 minute to 5 minutes. This makes it possible to sufficiently remove the solvent while suppressing the progress of curing of the resin film containing a thermosetting resin.

The resin film of this embodiment may be composed of a resin film alone, or may be composed to include a fiber substrate inside.

<Prepreg>
The prepreg of the present embodiment is configured to contain a fibrous base material in a resin composition. The prepreg is obtained by impregnating a fibrous base material with the resin composition.
For example, prepreg can be used as a sheet-like material obtained by impregnating a fiber substrate with a resin composition and then semi-curing the same. A sheet-like material having such a structure has excellent properties such as dielectric properties and mechanical and electrical connection reliability under high temperature and humidity, and is suitable for producing an insulating layer for a printed wiring board.

In this embodiment, the method of impregnating the fiber substrate with the resin composition is not particularly limited, but examples include a method of dissolving the resin composition in a solvent to prepare a resin varnish and immersing the fiber substrate in the resin varnish, a method of applying the resin varnish to the fiber substrate using various coaters, a method of spraying the resin varnish onto the fiber substrate using a sprayer, and a method of laminating both sides of the fiber substrate with the resin film made of the resin composition.

Examples of the fiber substrate include glass fiber substrates such as woven glass cloth and nonwoven glass cloth, inorganic fiber substrates such as woven or nonwoven cloth containing inorganic compounds other than glass, and organic fiber substrates made of organic fibers such as aromatic polyamideimide resin, polyamide resin, aromatic polyester resin, polyester resin, polyimide resin, and fluororesin. Among these substrates, the use of glass fiber substrates such as woven glass cloth, which is representative of the strength of these substrates, can improve the mechanical strength and heat resistance of the printed wiring board.

The thickness of the fiber base material is not particularly limited, but is preferably 5 μm to 150 μm, more preferably 10 μm to 100 μm, and even more preferably 12 μm to 90 μm. By using a fiber base material having such a thickness, the handleability during prepreg production can be further improved.
When the thickness of the fiber substrate is equal to or less than the upper limit, the impregnation of the resin composition in the fiber substrate is improved, and the occurrence of strand voids and deterioration of insulation reliability can be suppressed. In addition, the formation of through holes by carbon dioxide, UV, excimer, or other lasers can be facilitated. In addition, when the thickness of the fiber substrate is equal to or more than the lower limit, the strength of the fiber substrate and prepreg can be improved. As a result, the handling property can be improved, the preparation of prepreg can be facilitated, and the warping of the resin substrate can be suppressed.

As the glass fiber substrate, for example, a glass fiber substrate formed from one or more types of glass selected from E glass, S glass, D glass, T glass, NE glass, UT glass, L glass, HP glass, and quartz glass is preferably used.

In this embodiment, the prepreg can be used, for example, to form an insulating layer in a build-up layer or an insulating layer in a core layer in a printed wiring board. When the prepreg is used to form an insulating layer in a core layer in a printed wiring board, for example, two or more prepregs can be stacked and the resulting laminate can be heat-cured to form an insulating layer for the core layer.

<Metal-clad laminate>
The laminate of the present embodiment is a metal-clad laminate in which a metal layer is disposed on at least one surface of the cured product of the prepreg.

A method for producing a metal-clad laminate using a prepreg is, for example, as follows.
A metal foil is placed on both the upper and lower sides or one side of the outer side of a prepreg or a laminate of two or more prepregs, and these are bonded under high vacuum conditions using a laminator or Becquerel device, or a metal foil is placed on both the upper and lower sides or one side of the outer side of the prepreg as is. When two or more prepregs are laminated, a metal foil is placed on both the upper and lower sides or one side of the outermost side of the laminated prepreg. Next, a metal-clad laminate can be obtained by hot-press molding the laminate of the prepreg and the metal foil. Here, it is preferable to continue pressing until the end of cooling during hot-press molding.

Examples of metals constituting the metal foil include copper, copper-based alloys, aluminum, aluminum-based alloys, silver, silver-based alloys, gold, gold-based alloys, zinc, zinc-based alloys, nickel, nickel-based alloys, tin, tin-based alloys, iron, iron-based alloys, Fe-Ni-based alloys such as Kovar (trade name), 42 alloy, Invar, and Super Invar, W, and Mo. Among these, the metal constituting the metal foil 105 is preferably copper or a copper alloy because it has excellent conductivity, is easy to form a circuit by etching, and is inexpensive. That is, the metal foil 105 is preferably copper foil.
As the metal foil, a metal foil with a carrier or the like can also be used.
The thickness of the metal foil is preferably 0.5 μm or more and 20 μm or less, and more preferably 1.5 μm or more and 18 μm or less.

<Resin film with carrier>
Next, the resin film with a carrier of this embodiment will be described.
FIG. 1 is a diagram showing an example of the configuration of a resin film 10 with a carrier.

An example of the above-mentioned carrier-attached resin film 10 includes a carrier substrate 30 and a resin film 20 made of a resin composition provided on the carrier substrate 30.

The resin film 10 with a carrier may be in the form of a roll that can be wound up as shown in FIG. 1(a), or in the form of rectangular sheets.

As the carrier substrate 30, for example, a polymer film or a metal foil can be used. The polymer film is not particularly limited, but examples thereof include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, release paper such as silicone sheets, and heat-resistant thermoplastic resin sheets such as fluorine-based resins and polyimide resins. The metal foil is not particularly limited, but examples thereof include copper and/or copper-based alloys, aluminum and/or aluminum-based alloys, iron and/or iron-based alloys, silver and/or silver-based alloys, gold and gold-based alloys, zinc and zinc-based alloys, nickel and nickel-based alloys, and tin and tin-based alloys. Among these, a sheet made of polyethylene terephthalate is most preferable because it is inexpensive and the peel strength can be easily adjusted. This makes it easy to peel off the resin film 10 with the carrier with an appropriate strength.

The surface of the carrier-attached resin film 10 may be exposed or may be covered with a protective film (cover film 50), for example. As the protective film, a film having a known protective function may be used, for example, a PET film. As shown in FIG. 1(b), the resin film 20 may be formed between the carrier substrate 30 and the cover film 50. This improves the handleability of the resin film 20.

The resin film 20 of the carrier-attached resin film 10 of this embodiment may be a single layer or a multilayer, and may be composed of one or more types of films. When the resin sheet is multilayered, it may be composed of the same type or different types.

The lower limit of the thickness of the resin film 20 is, for example, 5 μm or more, and preferably 10 μm or more. This can improve the insulation reliability. On the other hand, the upper limit of the thickness of the resin film 20 is, for example, 50 μm or less, and preferably 40 μm or less. This can realize a thinner printed wiring board. In addition, by setting the thickness of the resin film 20 within the above range, when manufacturing the printed wiring board, it is possible to fill and mold the unevenness of the inner layer circuit, and it is possible to ensure a suitable thickness of the insulating resin layer of the build-up layer.

The thickness of the carrier substrate 30 is not particularly limited, but may be, for example, 10 to 100 μm, or 10 to 70 μm. This is preferable because it improves the handleability when manufacturing the carrier-attached resin film 10.

<Printed wiring board>
The printed wiring board of this embodiment includes an insulating layer made of the cured product of the above-mentioned resin film (cured product of the resin composition).
In this embodiment, the cured resin film can be used, for example, as a build-up layer of a normal printed wiring board, a build-up layer in a printed wiring board having no core layer, a build-up layer of a coreless substrate used in PLP, a build-up layer of an MIS substrate, etc. The insulating layer constituting such a build-up layer can also be suitably used as a build-up layer constituting a large-area printed wiring board used to collectively produce a plurality of semiconductor packages.

In addition, in this embodiment, the resin film made of the resin composition for forming the insulating film can be configured to be impregnated with glass fibers. Even in a semiconductor package using such a resin film in the build-up layer, the linear expansion coefficient of the cured resin film can be reduced, so package warpage can be sufficiently suppressed.

<Semiconductor package>
2A to 2C are cross-sectional views showing an example of a manufacturing process for the semiconductor package 200 of this embodiment.
The semiconductor device (semiconductor package 200) of this embodiment can include a printed wiring board and a semiconductor element 240 mounted on a circuit layer of the printed wiring board or embedded in the printed wiring board.

An outline of the manufacturing process for the semiconductor package 200 of this embodiment will be described below.
First, as shown in FIG. 2(a), a core layer 100 including an insulating layer 102, a via hole 104, and a metal layer 108 is prepared. A via hole 104 is formed in the insulating layer 102. A metal layer (via) is embedded in the via hole 104. The metal layer may be covered with an electroless metal plating film 106. The metal layer 108 (a circuit layer having a predetermined circuit pattern) formed on the surface of the insulating layer 102 is electrically connected to the via formed in the via hole 104. In FIG. 2(a), the metal layer 108 is formed on one surface of the core layer 100, but it may be formed on both surfaces.

Next, a resin film 20 made of the above resin composition is formed on one surface of the core layer 100 so as to embed the metal layer 108. For example, the cover film 50 may be peeled off from the carrier-attached resin film 10, and the resin film 20 (insulating film) may be placed on the circuit-forming surface of the core layer 100. A carrier base material 30 is provided on the surface of this resin film 20. The carrier base material 30 may be separated from the resin film 20 at this point, or may be used as a mask.
The resin film 20 may be a single insulating layer, or may be made up of multiple layers including an insulating layer and a primer layer.

Next, an opening (not shown) is formed in the resin film 20 via the carrier substrate 30. The opening can be formed so as to expose the metal layer 108. The method for forming the opening is not particularly limited, and can be, for example, a laser processing method, an exposure and development method, or a blasting method.

In this embodiment, after forming such openings, the resin film 20 may be thermally cured. Then, the carrier substrate 30 is peeled off.

If necessary, a desmear process can be performed. The desmear process removes smears that have formed inside the openings and roughens the surface of the resin film 20.

The method of the desmearing process is not particularly limited, but can be performed, for example, as follows. First, the core layer 100 on which the resin film 20 is laminated is immersed in a swelling liquid containing an organic solvent, and then immersed in an alkaline permanganate aqueous solution to neutralize and roughen the layer. As the organic solvent, diethylene glycol monobutyl ether, ethylene glycol, etc. can be used. As such a swelling liquid, for example, "Swelling Dip Securigant P" manufactured by Atotech Japan can be used. As the permanganate, for example, potassium permanganate, sodium permanganate, etc. can be used. The liquid temperature of the swelling liquid or the permanganate aqueous solution may be, for example, 50°C or higher and 100°C or lower. The immersion time in the swelling liquid or the permanganate aqueous solution may be, for example, 1 minute or more and 30 minutes or less.

In the desmear process, only the wet desmear process described above can be performed, but plasma irradiation may also be performed in addition to the desmear process.

Next, an electroless metal plating film 202 is formed on the resin film 20 or on a primer layer (not shown) formed on the resin film 20. An example of an electroless plating method will be described. For example, catalytic nuclei are applied to the surface of the base layer. The catalytic nuclei are not particularly limited, but for example, precious metal ions or palladium colloids can be used. Then, using the catalytic nuclei as nuclei, an electroless plating process is performed to form an electroless metal plating film 202. For electroless plating, for example, a solution containing copper sulfate, formalin, a complexing agent, sodium hydroxide, etc. can be used. After electroless plating, a heat treatment at 100 to 250°C can be performed to stabilize the plating film.

Next, as shown in FIG. 2B, a resist 204 having a predetermined opening pattern (openings 206) may be formed on the electroless metal plating film 202. This opening pattern corresponds to, for example, a circuit pattern. The resist 204 is not particularly limited and may be any known material, but may be liquid or dry film. In the case of forming fine wiring, the resist 204 may be a photosensitive dry film or the like. An example using a photosensitive dry film will be described. For example, a photosensitive dry film is laminated on the electroless metal plating film 202, the non-circuit formation area is exposed to light to harden, and the unexposed area is dissolved and removed with a developer. The hardened photosensitive dry film is left behind to form the resist 204.

Next, as shown in FIG. 2(c), an electrolytic metal plating layer 208 is formed by electroplating at least inside the opening pattern of the resist 204 and on the electroless metal plating film 202. Although there is no particular limitation on the electroplating, a known method used in ordinary printed wiring boards can be used, for example, a method of passing an electric current through a plating solution such as copper sulfate while immersed in the plating solution can be used. The electrolytic metal plating layer 208 may be a single layer or may have a multi-layer structure. Although there is no particular limitation on the material of the electrolytic metal plating layer 208, for example, one or more of copper, copper alloy, 42 alloy, nickel, iron, chromium, tungsten, gold, and solder can be used.

Next, as shown in FIG. 2(d), the resist 204 is removed using an alkaline stripping solution, sulfuric acid, or a commercially available resist stripping solution.

Next, as shown in FIG. 2(e), the electroless metal plating film 202 is removed from the area (opening 210) other than the area where the electrolytic metal plating layer 208 is formed. That is, the electroless metal plating film 202 of the lower layer is selectively removed using the electrolytic metal plating layer 208 as a mask. For example, the electroless metal plating film 202 can be removed by using soft etching (flash etching) or the like. Here, the soft etching process can be performed by etching using an etching solution containing, for example, sulfuric acid and hydrogen peroxide. This allows the metal layer 220 having a predetermined pattern to be formed. In this way, the metal layer 220 composed of the electroless metal plating film 202 and the electrolytic metal plating layer 208 can be formed on the insulating layer made of the cured product of the resin film of this embodiment by the semi-additive process (SAP).

Furthermore, a multi-layer structure can be formed by stacking build-up layers as necessary on a printed wiring board composed of the core layer 100 and the above-mentioned build-up layers, and repeating the process of forming interlayer connections and circuits by a semi-additive process.
In this manner, the printed wiring board of the present embodiment is obtained.

Next, as shown in FIG. 2(f), build-up layers are laminated on the obtained printed wiring board as necessary, and the process of forming interlayer connections and circuits by a semi-additive process is repeated. Then, as necessary, a solder resist layer 230 is laminated on both sides or one side of the printed wiring board.

The method for forming the solder resist layer 230 is not particularly limited, but may be, for example, a method in which a dry film type solder resist is laminated, exposed to light, and developed, or a method in which a liquid resist is printed and then exposed to light and developed.

Next, a reflow process is performed to fix the semiconductor element 240 onto the connection terminals, which are part of the wiring pattern, via the solder bumps 250. Thereafter, the semiconductor element 240, the solder bumps 250, etc. are covered with a sealing material layer 260 for sealing.
As a result of the above, a semiconductor package 200 shown in FIG.

The above describes the embodiments of the present invention, but these are merely examples of the present invention, and various configurations other than those described above can be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of the present invention are included in the present invention.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to the description of these examples.

(Preparation of Resin Composition)
Each component was dissolved or dispersed in the solid content ratio shown in Table 1, adjusted with methyl ethyl ketone so that the non-volatile content was 70 mass %, and stirred using a high-speed stirrer to prepare a varnish-like resin composition (resin varnish P).
The numerical values showing the blending ratio of each component in Table 1 indicate the blending ratio (mass %) of each component relative to the total solid content of the resin composition.

Details of the raw materials for each component in Table 1 are as follows.
(A) Modified polyphenylene ether: polyphenylene ether modified with a terminal methacrylic group, "SA9000" manufactured by SABIC Innovative Plastics (B) Maleimide compound: biphenylaralkyl-type maleimide compound, "MIR-3000-70MT" manufactured by Nippon Kayaku Co., Ltd. (C) Indene resin: indene-coumarone-styrene copolymer containing a phenol group at the end (manufactured by Nippon Paint Chemical Co., Ltd., V-120S, weight average molecular weight: 950, hydroxyl value: 30 mg KOH/g)
(D) Polybutadiene-based elastomer: polybutadiene, "B-1000" manufactured by Nippon Soda Co., Ltd. (E) Phenol having an unsaturated double bond: allylphenol, "FATC-809" manufactured by Gun-ei Chemical Co., Ltd. (F) Multifunctional vinyl compound: triallyl isocyanate, crosslinking agent, "TAIC" manufactured by Mitsubishi Chemical Corporation (G) Inorganic filler: silica particles, "SC4050" manufactured by Admatechs Co., Ltd. (average particle size 1.1 μm, surface treated with aminophenoxysilane)
(H) Flame retardant: Condensed phosphate ester "PX-200" manufactured by Daihachi Chemical Industry Co., Ltd. (others)
Polymerization initiator: 1,4-bis[(t-butylperoxy)isopropyl]benzene "Perbutyl P" manufactured by NOF Corporation

In each of the examples and comparative examples, the obtained resin varnish P (resin composition) was used to prepare a prepreg, a resin substrate with metal foil, and a printed wiring board as follows.

(Preparation of prepregs and laminates with metal foil)
The obtained resin varnish was impregnated into a glass woven fabric (cloth type #1078, NE glass, basis weight 44 g/m ² ) using a coating device, and dried for 10 minutes in a hot air dryer at 140° C. to obtain a prepreg with a thickness of 70 μm.
Ultra-thin copper foil (Mitsui Mining & Smelting Co., Ltd., Microthin FL, 1.5 μm) was laminated on both sides of the prepreg, and the laminate was heated and pressurized for 2 hours at a pressure of 3 MPa and a temperature of 225° C. to obtain a laminate with metal foil. The thickness of the core layer (portion made of resin substrate) of the obtained laminate with metal foil was 0.070 mm.

(Fabrication of printed wiring boards)
Using the obtained laminate with metal foil, a drill was used to open a predetermined portion, and the conductive layer was formed by electroless plating. The copper foil was etched to produce a core layer with a circuit formation surface and a remaining copper of 60%. Next, prepreg 1 was placed on both sides of the core layer, and ultra-thin copper foil (Mitsui Mining & Smelting Co., Ltd., Microsyn FL, 1.5 μm) was superimposed, and the laminate was heated and pressurized for 2 hours at a pressure of 3 MPa and a temperature of 225 ° C. Next, via holes were formed in the obtained laminate by a carbon dioxide laser. The inside of the via was immersed in a swelling liquid (Atotech Japan, Swelling Dip Securigant P) at 60 ° C. for 5 minutes, and further immersed in an aqueous potassium permanganate solution (Atotech Japan, Concentrate Compact CP: sodium permanganate concentration 60 g / l, NaOH concentration 45 g / l) at 80 ° C. for 15 minutes, and then neutralized and roughened.
After the process of degreasing, catalyst application, and activation, an electroless copper plating film of about 0.5 μm was formed, a resist was formed, and a pattern of electroplated copper of 20 μm was formed using the electroless copper plating film as a power supply layer, and a circuit was processed. Next, an annealing treatment was performed for 60 minutes at 200 ° C. in a hot air drying device, and then the power supply layer was removed by flash etching. Next, a solder resist layer was formed, and an opening was formed so that the semiconductor element mounting pad and the like were exposed. Finally, a plating layer consisting of an electroless nickel plating layer of 3 μm and an electroless gold plating layer of 0.1 μm was formed on the circuit layer exposed from the solder resist layer, and the obtained board was cut into a size of 50 mm × 50 mm to obtain a printed wiring board.

The prepregs, metal foil laminates, and printed wiring boards obtained using the above resin varnish P (resin composition) were evaluated based on the following evaluation items and in accordance with the criteria shown in Table 2. The results are shown in Table 1. In Table 2, the range of values "-" indicates a range between the lower limit and the upper limit, or between the lower limit and the upper limit.

1) Peel strength The peel strength was measured in accordance with JIS C 6481. The sample used was a resin substrate with metal foil and electroplated copper of 30 μm.

2) Peel strength of plated copper after HAST Using the obtained laminate with metal foil, the peel strength of the plated copper after the above-mentioned roughening treatment was measured at 23°C in accordance with JIS C-6481: 1996. Note that as a pretreatment, a moisture absorption treatment was performed at a temperature of 130°C, a humidity of 85%, and for 100 hours.

3) Glass transition temperature: The glass transition temperature was measured using a dynamic viscoelasticity device in accordance with JIS C-6481 (DMA method). The sample used was a laminate with a metal foil from which copper had been removed by etching.

4) Thermal expansion coefficient The thermal expansion coefficient was measured by preparing a 4 mm x 20 mm test piece using a TMA (thermomechanical analysis) device (Q400, manufactured by TA Instruments) and measuring the linear expansion coefficient (CTE) at 50 to 100°C in the second cycle under the conditions of a temperature range of 30 to 300°C, 10°C/min, and a load of 5 g. The sample used was a laminate with metal foil that had been etched to remove the copper.

5, 6) Dielectric loss tangent The laminate with metal foil was etched to remove the copper, and the dielectric loss tangent was measured using a 10 GHz cavity resonator.

7) Moldability The moldability was evaluated by visually inspecting the embeddability of the outer copper foil of the printed wiring board in the inner layer pattern and by observing the cross section after etching the entire surface of the outer copper foil.

8) Moisture absorption solder heat resistance All of the copper foil of a metal foil-attached laminate was removed by etching except for half of one side of a 50 mm × 50 mm square sample, and the sample was treated for a predetermined time at 121°C and 2 atm in a pressure cooker tester (manufactured by Espec Corp.), and then floated in a solder bath at 260°C for 60 seconds, and the presence or absence of abnormal changes in appearance was visually observed.

9) Laser processability The periphery of the bottom of the via hole of the printed wiring board was observed with a scanning electron microscope (SEM), and the maximum smear length from the wall surface of the bottom of the via hole was measured from the obtained image. The smear removability was evaluated according to the following criteria.

10) Insulation The through-hole insulation reliability was evaluated by continuous measurement at a through-hole wall distance of 0.1 mm in the printed wiring board, under conditions of an applied voltage of 5.5 V, a temperature of 130° C., and a humidity of 85%. The measurement was terminated when the insulation resistance value became less than 106Ω.

11) Flammability In the manufacturing process of the metal foil-attached laminate described above, five of the prepregs were stacked, and 12 μm copper foil was stacked on both sides of the stack, followed by heat-pressure molding at a pressure of 3 MPa and a temperature of 225° C. for 2 hours to obtain a double-sided copper-clad laminate having a thickness of 0.35 mm. The copper foil of the double-sided copper-clad laminate obtained above was etched, and the flammability was measured by the vertical method according to the UL-94 standard.

10 Resin film with carrier 20 Resin film 30 Carrier base material 50 Cover film 100 Core layer 102 Insulating layer 104 Via hole 106 Electroless metal plating film 108 Metal layer 200 Semiconductor package 202 Electroless metal plating film 204 Resist 206 Opening 208 Electrolytic metal plating layer 210 Opening 220 Metal layer 230 Solder resist layer 240 Semiconductor element 250 Solder bump 260 Sealing material layer

Claims (16)

A resin composition comprising the following components (A) to (C):
(A) a modified polyphenylene ether in which a phenolic hydroxyl group at a molecular end of a polyphenylene ether is modified with a compound having a carbon-carbon unsaturated double bond, the modified polyphenylene ether being contained in an amount of 1 part by weight or more and 30 parts by weight or less relative to 100 parts by weight of the resin solid content of the resin composition; (B) a maleimide compound being contained in an amount of 5 parts by weight or more and 40 parts by weight or less relative to 100 parts by weight of the resin solid content of the resin composition; (C) an indene resin being contained in an amount of 1 part by weight or more and 20 parts by weight or less relative to 100 parts by weight of the resin solid content of the resin composition. The resin composition according to claim 1, wherein the dielectric tangent of the cured product of the resin composition at 10 GHz is 0.006 or less. The resin composition according to claim 1 or 2, further comprising the following component (D):
(D) Polybutadiene-based elastomer The resin composition according to claim 3, wherein the weight ratio (B/D) of component (B) to component (D) is 0.5 to 8. The resin composition according to claim 1 , wherein the weight average molecular weight of the component (A) is 500 or more and 5,000 or less. The resin composition according to claim 1 , further comprising the following component (E):
(E) Phenol having an unsaturated double bond The resin composition according to claim 1 , further comprising the following component (F):
(F) Polyfunctional vinyl compound The resin composition according to claim 1 , further comprising the following component (G):
(G) Inorganic filler The resin composition according to claim 8 , wherein the content of the component (G) is 50 parts by weight or more and 80 parts by weight or less per 100 parts by weight of the resin solid content. The resin composition according to claim 1 , further comprising the following component (H):
(H) Flame retardants A cured product of the resin composition according to any one of claims 1 to 10 . A prepreg comprising a fiber base material in the resin composition according to any one of claims 1 to 10 . A laminate comprising the prepreg according to claim 12 and a metal layer disposed on at least one surface of the prepreg. A carrier substrate;
A resin film formed on the carrier substrate and made of the resin composition according to claim 1 ;
A resin film with a carrier. A printed wiring board comprising an insulating layer made of a cured product of the resin composition according to claim 1 . The printed wiring board according to claim 15 ;
a semiconductor element mounted on a circuit layer of the printed wiring board or embedded in the printed wiring board.

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