Cured product of resin composition, wiring board, and semiconductor package

Abstract

One aspect of the present invention relates to a cured resin composition comprising a filler material having a 50% particle size D50 of a volume-based cumulative particle size distribution of the filler material of less than 2100 nm, the filler material comprising less than 35% by mass relative to the resin composition, the cured material having a relative permittivity of less than 2.6 at 10 GHz, and the cured material having a surface roughness Ra of less than 100 nm.

Description

Technical Field

[0001] This invention relates to cured resin compositions, wiring boards, and semiconductor packages. Background Technology

[0002] For various electronic devices, with the increase in information processing volume, mounting technologies such as high integration of semiconductor devices, high-density wiring, and multi-layering are becoming increasingly advanced. Furthermore, wiring boards used in various electronic devices include insulating layers in rewiring layers such as build-up layers used in multi-layering. Examples of insulating layers in such wiring boards include the insulating layer in the adhesive film described in Patent Document 1, and the curing layer in the printed wiring board described in Patent Document 2.

[0003] Patent Document 1 discloses an adhesive film comprising a support and a resin composition layer, wherein the arithmetic mean roughness Ra1 of the surface of the support in contact with the resin composition layer is 200 nm or more, and the dielectric loss factor of the insulating layer formed by thermosetting the resin composition layer is 0.005 or less, and the support is a film formed of a plastic material or a film formed of a plastic material with a release layer. Patent Document 1 discloses that even with a low dielectric loss factor, the adhesion of the dry film can be improved.

[0004] Patent Document 2 discloses a printed wiring board comprising a cured layer formed by thermosetting a resin composition containing a thermosetting resin. The cured layer includes a first via hole formed on one side surface of the cured layer and a second via hole formed on the same surface. The first via hole has a first opening with a diameter of 50 μm or more and is formed to penetrate the cured layer through the first opening. The second via hole has a second opening with a diameter of 32 μm or less and is formed to penetrate the cured layer through the second opening. The thickness of the cured layer is 25 μm or less, and the elastic modulus of the cured layer at 25°C is 5 GPa or more and 15 GPa or less. Patent Document 2 discloses methods to suppress crack initiation and warping, and to efficiently form both large-aperture via holes formed by sandblasting and small-aperture via holes formed by laser processing simultaneously. Furthermore, it discloses the use of materials with high insulation reliability to manufacture printed wiring boards with via holes of different opening diameters in the same cured layer, thereby enabling the design of more complex and precise semiconductor devices than before.

[0005] For wiring boards used in various electronic devices, such as substrates for servers used in communication infrastructure, there is a need for wiring boards that can handle high frequencies. For this reason, wiring boards used in various electronic devices are required to improve signal transmission speed. Therefore, the wiring boards are required to reduce signal transmission losses. Specifically, the wiring boards are required to have an insulating layer that reduces signal transmission losses compared to conventional wiring boards (e.g., wiring boards with an insulating layer in the adhesive film described in Patent Document 1, and printed wiring boards described in Patent Document 2). Furthermore, the insulating layer of the wiring board is, for example, a layer formed by processing a cured resin composition for wiring. Therefore, it is believed that when plasma treatment is performed as a wiring process, if the cured resin composition used for the insulating layer has low dielectric properties such as a low relative permittivity and low surface roughness after plasma treatment, signal transmission losses can be reduced.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Publication No. 2020-74444

[0009] Patent Document 2: Japanese Patent Publication No. 2022-70723 Summary of the Invention

[0010] This invention was made in view of the aforementioned circumstances, and its object is to provide a cured product of a resin composition with low dielectric properties such as relative permittivity and low surface roughness after plasma treatment. Furthermore, an object of this invention is to provide a wiring board and a semiconductor package obtained using the cured product of the resin composition.

[0011] One aspect of the present invention relates to a cured resin composition comprising a filler material having a 50% particle size D50 of a volume-based cumulative particle size distribution of the filler material of less than 2100 nm, the filler material comprising less than 35% by mass relative to the resin composition, the cured material having a relative permittivity of less than 2.6 at 10 GHz, and the cured material having a surface roughness Ra of less than 100 nm.

[0012] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description and accompanying drawings. Attached Figure Description

[0013] Figure 1 This is a schematic diagram illustrating an example of a method for manufacturing a wiring board using a cured material according to an embodiment of the present invention.

[0014] Figure 2 This is a schematic diagram illustrating another example of a method for manufacturing a wiring board using a cured material according to an embodiment of the present invention. Detailed Implementation

[0015] The following describes the embodiments of the present invention, but the present invention is not limited to these embodiments.

[0016] The inventors have conducted various studies and found that the above-mentioned objectives can be achieved through the following invention.

[0017] [Cure of the resin composition]

[0018] The cured product of the resin composition according to the embodiments of the present invention is a cured product obtained by curing a resin composition containing a filler material. The filler material has a 50% particle size D50 of 2100 nm or less in its cumulative particle size distribution based on volume, and its content is less than 35% by mass relative to the resin composition. Furthermore, the cured product has a relative permittivity of less than 2.6 at 10 GHz and a surface roughness Ra of less than 100 nm. With such a cured product, a cured product with low dielectric properties such as relative permittivity and low surface roughness after plasma treatment can be obtained. Specifically, even after plasma treatment of the cured product to form conductor wiring patterns, etc., on the cured product with a low dielectric loss factor, a cured product with a surface roughness Ra of, for example, less than 100 nm can be obtained, maintaining a low surface roughness. As described above, the relatively permittivity of less than 2.6 at 10 GHz and the surface roughness Ra of less than 100 nm after plasma treatment result in a low surface roughness, thus reducing signal transmission losses in the conductor wiring (conductor circuit) formed on the cured product.

[0019] (Filling material)

[0020] The filler material has a cumulative particle size distribution in which 50% of the particle size D50 is 2100 nm or less, preferably 100–700 nm, more preferably 100–600 nm, and even more preferably 100–500 nm. By using a filler material with this particle size distribution, a cured product with a low surface roughness Ra after plasma treatment can be obtained. This is believed to be based on the following reasoning: The filler material contained in the resin composition is a filler material with a low content of fillers with excessively large particle sizes, where 50% of the particle size D50 is 2100 nm or less. Therefore, it is believed that by curing a resin composition containing a filler material with this particle size distribution, a cured product with a low surface roughness Ra after plasma treatment can be obtained.

[0021] The filler material is not particularly limited as long as 99% of the particle size D99 in the cumulative particle size distribution based on volume is 2500 nm or less. The 99% particle size D99 being 2500 nm or less is preferably 700–1500 nm, more preferably 700–1000 nm. By using a filler material with this particle size distribution, a cured product with a low surface roughness Ra after plasma treatment can be obtained more effectively. This is based on the following reasons: First, the 99% particle size D99 is considered to be the maximum particle size of particles other than the unavoidably large particles. Therefore, it is considered that the filler material contained in the resin composition is a filler material with a low content of filler material with an excessively large particle size and 99% particle size D99 of 2500 nm or less. Therefore, it is considered that by curing a resin composition containing a filler material with this particle size distribution, a cured product with a low surface roughness Ra after plasma treatment can be obtained.

[0022] The 90% particle size D90 in the cumulative particle size distribution based on volume of the filler material is preferably 700–2300 nm, more preferably 700–1500 nm, and even more preferably 700–800 nm. By using a filler material having the particle size distribution described above as the filler material, a cured product with a lower surface roughness Ra after plasma treatment can be obtained.

[0023] It should be noted that the cumulative particle size distribution of the volumetric reference can be determined using known methods such as dynamic light scattering, centrifugal sedimentation, and laser diffraction scattering. Furthermore, the 50% particle size D50 refers to the particle size that reaches 50% from the smallest side of the cumulative particle size distribution of the volumetric reference. That is, D50 is the cumulative 50% particle size obtained by laser diffraction scattering particle size distribution determination, and is the particle size referred to as the median particle size. The 99% particle size D99 refers to the particle size that reaches 99% from the smallest side of the cumulative particle size distribution of the volumetric reference. Additionally, the 90% particle size D90 refers to the particle size that reaches 90% from the smallest side of the cumulative particle size distribution of the volumetric reference.

[0024] The filler material is not particularly limited and can be, for example, organic or inorganic particles. The organic particles are not particularly limited and can include, for example, acrylic particles, acrylonitrile particles, silicone particles, polycarbonate particles, polyolefin particles, polyester particles, polystyrene particles, melamine resin particles, and polyamide particles. Among the organic particles, acrylic particles, polystyrene particles, and polyolefin particles are preferred. The inorganic particles are not particularly limited and can include, for example, silica particles, titanium dioxide particles, alumina particles, tin oxide particles, indium oxide particles, zinc oxide particles, zirconium oxide particles, magnesium oxide particles, calcium carbonate particles, calcium carbonate particles, aluminum hydroxide particles, barium sulfate particles, and glass beads. Furthermore, the filler material can also be hollow particles; specifically, examples include organic hollow particles such as hollow polystyrene particles and inorganic hollow particles. Among the filler materials, polystyrene particles, hollow polystyrene particles, inorganic particles, and inorganic hollow particles are preferred, and polystyrene particles, hollow polystyrene particles, silica particles, and hollow silica particles are more preferred. Furthermore, the filler materials can be used alone or in combination of two or more.

[0025] The resin composition contains the filler material as described above in such a manner that its content is less than 35% by mass relative to the resin composition and that the relative permittivity of the cured resin composition is less than 2.6 at 10 GHz.

[0026] The content of the filler material relative to the resin composition is less than 35% by mass, preferably less than 30% by mass, and more preferably less than 25% by mass. A lower content of the filler material is preferable; practically, it is more preferably 5% by mass or more, more preferably 7% by mass or more, so that the cured resin composition can be used as an insulating layer in a wiring board. Therefore, it is preferably 5% by mass or more and less than 35% by mass, more preferably 5 to 30% by mass, and even more preferably 7 to 25% by mass. If the content of the filler material is too high, there is a tendency for the relative permittivity of the resin composition to become too high, which may prevent the requirement that the relative permittivity of the cured resin composition at 10 GHz be less than 2.6.

[0027] (Elastomer)

[0028] The resin composition is not particularly limited as long as it contains the filler material. Preferably, the resin composition also contains an elastomer.

[0029] The elastomer is not particularly limited, and examples include elastomers contained in resin compositions used to form insulating layers in metal-clad laminates and wiring boards. The resin compositions used to form insulating layers in metal-clad laminates and wiring boards can be resin compositions used to form resin layers in resin-coated films and resin-coated metal foils, or resin compositions contained in prepregs. Examples of such elastomers include styrene-based polymers.

[0030] The styrene-based polymer is, for example, a polymer obtained by polymerizing monomers containing styrene-based monomers, and can be a styrene-based copolymer. Furthermore, examples of styrene-based copolymers include copolymers obtained by copolymerizing one or more of the aforementioned styrene-based monomers with one or more other monomers capable of copolymerizing with the aforementioned styrene-based monomers. The styrene-based copolymer can be a random copolymer or a block copolymer as long as it has a structure derived from the aforementioned styrene-based monomer within its molecule. Examples of block copolymers include: binary copolymers of a structure (repeating unit) derived from the aforementioned styrene-based monomer and the other monomers capable of copolymerizing (repeating units); ternary copolymers of a structure (repeating unit) derived from the aforementioned styrene-based monomer, the other monomers capable of copolymerizing (repeating units), and a structure (repeating unit) derived from the aforementioned styrene-based monomer; and ternary copolymers of a structure (repeating unit) derived from the aforementioned styrene-based monomer, comprising a random copolymer block (repeating unit) containing the other monomers capable of copolymerizing and the aforementioned styrene-based monomer, and a structure (repeating unit) derived from the aforementioned styrene-based monomer. The styrene-based polymer can also be a hydrogenated styrene-based copolymer obtained by hydrogenating the aforementioned styrene-based copolymer. The styrene-based polymer can also be a substance in which a portion of the copolymer is modified with maleic anhydride.

[0031] The styrene-based monomers are not particularly limited, and examples include styrene, styrene derivatives, substances in which some hydrogen atoms of the benzene ring in styrene are replaced by alkyl groups, substances in which some hydrogen atoms of the vinyl group in styrene are replaced by alkyl groups, vinyltoluene, α-methylstyrene, butylstyrene, dimethylstyrene, and isopropenyltoluene, etc. These styrene-based monomers can be used alone or in combination of two or more. Furthermore, the other monomers capable of copolymerization are not particularly limited, and examples include: olefins such as α-pinene, β-pinene, and dipentene; non-conjugated dienes such as 1,4-hexadiene and 3-methyl-1,4-hexadiene; and conjugated dienes such as 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene), etc. These other monomers capable of copolymerization can be used alone or in combination of two or more.

[0032] As the styrene-based polymer, conventionally known styrene-based polymers can be widely used without particular limitation. Examples include polymers that have structural units (derived from the structure of the styrene-based monomer) in the molecule as shown in formula (4).

[0033]

[0034] In formula (1), R1 to R3 each independently represent a hydrogen atom or an alkyl group, and R4 represents any group selected from the group consisting of hydrogen atoms, alkyl groups, alkenyl groups, and isopropenyl groups. The alkyl group is not particularly limited; for example, it is preferably an alkyl group having 1 to 18 carbon atoms, and more preferably an alkyl group having 1 to 10 carbon atoms. Specifically, examples include methyl, ethyl, propyl, hexyl, and decyl groups. Furthermore, the alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms.

[0035] The styrene-based polymer preferably contains at least one structural unit as shown in formula (1), and may also contain two or more different structural units. Furthermore, the styrene-based polymer may also contain a structure that repeats the structural unit shown in formula (1).

[0036] The styrene-based polymer not only has the structural unit shown in formula (1), but may also have at least one of the structural units shown in formula (2), formula (3) and formula (4) and the structural units shown in formula (1), formula (2) and formula (3) respectively as structural units derived from other monomers that can copolymerize with the styrene-based monomer.

[0037]

[0038]

[0039]

[0040] In equations (2), (3), and (4), R5~R 22 Each of these terms independently represents any group selected from the group consisting of hydrogen atoms, alkyl, alkenyl, and isopropenyl. The alkyl group is not particularly limited; for example, it is preferably an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms. Specifically, examples include methyl, ethyl, propyl, hexyl, and decyl. Furthermore, the alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms.

[0041] The styrene-based polymer preferably contains at least one of the structural units shown in formula (2), formula (3), and formula (4), and may also contain a combination of two or more different structural units. Furthermore, the styrene-based polymer may also have a structure that repeats at least one of the structural units shown in formula (2), formula (3), and formula (4).

[0042] More specifically, structural units represented by equation (1) can be listed as structural units represented by equations (5) to (7) below. Furthermore, structural units represented by equation (1) can be structures that repeat the structural units represented by equations (5) to (7) below. The structural unit represented by equation (1) can be a single unit or a combination of two or more different structural units.

[0043]

[0044]

[0045]

[0046] More specifically, structural units represented by equation (2) can be listed as structural units represented by equations (8) to (14) below. Furthermore, structural units represented by equation (2) can be structures that repeat the structural units represented by equations (8) to (14) below. The structural unit represented by equation (2) can be a single unit or a combination of two or more different structural units.

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054] More specifically, structural units represented by equation (3) can be listed as structural units represented by equations (15) and (16) below. Furthermore, structural units represented by equation (3) can be structures that repeat the structural units represented by equations (15) and (16) below. The structural unit represented by equation (3) can be a single type or a combination of two or more different structural units.

[0055]

[0056]

[0057] More specifically, structural units represented by equation (4) can be listed as structural units represented by equations (17) and (18) below. Furthermore, structural units represented by equation (4) can be structures that repeat the structural units represented by equations (17) and (18) below. The structural unit represented by equation (4) can be a single type or a combination of two or more different structural units.

[0058]

[0059]

[0060] Preferred examples of the styrene-based copolymers include polymers or copolymers obtained by polymerizing or copolymerizing one or more styrene monomers such as styrene, vinyltoluene, α-methylstyrene, isopropyltoluene, divinylbenzene, and allylstyrene. More specifically, examples of the styrene-based copolymers include methylstyrene (ethylene / butene) methylstyrene copolymers, methylstyrene (ethylene-ethylene / propylene) methylstyrene copolymers, styrene-isoprene copolymers, styrene-isoprene-styrene copolymers, styrene (ethylene / butene) styrene copolymers, styrene (ethylene-ethylene / propylene) styrene copolymers, styrene-butadiene-styrene copolymers, butadiene-styrene-butadiene oligomers, styrene (butadiene / butene) styrene copolymers, methylstyrene (styrene / butadiene random copolymer block) methylstyrene copolymers, styrene (styrene / butadiene random copolymer block) styrene copolymers, and styrene-isobutylene-styrene copolymers. Examples of hydrogenated styrene-based copolymers include, for instance, hydrogenated versions of the styrene-based copolymers. More specifically, examples of hydrogenated styrene copolymers include hydrogenated methylstyrene (ethylene / butene) methylstyrene copolymer, hydrogenated methylstyrene (ethylene-ethylene / propylene) methylstyrene copolymer, hydrogenated styrene-isoprene copolymer, hydrogenated styrene-isoprene-styrene copolymer, hydrogenated styrene (ethylene / butene) styrene copolymer, hydrogenated styrene (ethylene-ethylene / propylene) styrene copolymer, hydrogenated methylstyrene (styrene / butadiene random copolymer block) methylstyrene copolymer, and hydrogenated styrene (styrene / butadiene random copolymer block) styrene copolymer, etc.

[0061] Commercially available products can also be used as the styrene-based polymers, such as V9827, V9461, 2002, and 7125F manufactured by Kuraray Co., Ltd., FTR2140 and FTR6125 manufactured by Mitsui Chemicals Co., Ltd., Tuftec H1041, Tuftec P1500, Tuftec H1221, and Tuftec M1913 manufactured by Asahi Kasei Corporation, liquid 1,2-SBS manufactured by Nippon Soda Co., Ltd., and Ricon 181 and Ricon 184 manufactured by Clayville Corporation.

[0062] The weight-average molecular weight of the elastomer (the styrene-based polymer) is preferably 1,000 to 300,000, more preferably 1,200 to 200,000. If the molecular weight is too low, the glass transition temperature or heat resistance of the cured resin composition tends to decrease. Furthermore, if the molecular weight is too high, the viscosity when the resin composition is made into a varnish-like form, or the viscosity of the resin composition during heat molding, tends to become too high. It should be noted that the weight-average molecular weight is any value obtained by a conventional molecular weight determination method; specifically, values ​​obtained using gel permeation chromatography (GPC) can be cited as examples.

[0063] The elastomers can be used alone or in combination of two or more.

[0064] (Curing compounds)

[0065] The resin composition may also contain at least one curing compound selected from the group consisting of polyphenylene ether compounds, maleimide compounds, and hydrocarbon compounds. Furthermore, the resin composition may also contain a curing agent. In the case where the resin composition contains the polyphenylene ether compound as the curing compound, the curing agent is preferably included in the resin composition. That is, the resin composition preferably contains both the polyphenylene ether compound and the curing agent. Furthermore, the resin composition preferably contains both a maleimide compound and a hydrocarbon compound.

[0066] (polyphenylene ether compound)

[0067] The polyphenylene ether compound is not particularly limited, and examples include polyphenylene ether compounds having carbon-carbon unsaturated double bonds at the ends. Examples of such polyphenylene ether compounds include: polyphenylene ether compounds having carbon-carbon unsaturated double bonds at the ends of the molecules; more specifically, examples include modified polyphenylene ether compounds whose ends are modified by substituents having carbon-carbon unsaturated double bonds, and polyphenylene ether compounds containing substituents having carbon-carbon unsaturated double bonds at the ends of the molecules.

[0068] Examples of substituents having carbon-carbon unsaturated double bonds include groups represented by formula (19) and groups represented by formula (20). That is, examples of polyphenylene ether compounds having at least one selected from groups represented by formula (19) and groups represented by formula (20) at the molecule end include polyphenylene ether compounds.

[0069]

[0070] In equation (19), R 23 ~R 25 Each is independent. That is, R 23~R 25 They can be the same group or different groups. R 23 ~R 25 represents a hydrogen atom or an alkyl group. Ar represents an aryl group. p represents 0 to 10. It should be noted that in the above formula (19), when p is 0, it means that Ar is directly bonded to the end of the polyphenylene ether.

[0071] The arylene group is not particularly limited. Examples of such arylene groups include monocyclic aromatic groups such as phenylene, and polycyclic aromatic groups such as naphthalene rings. In addition, the arylene group may also include derivatives in which the hydrogen atoms bonded to the aromatic ring are replaced by functional groups such as alkenyl, alkynyl, formyl, alkyl carbonyl, alkenyl carbonyl, or alkynyl carbonyl.

[0072] 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. Specifically, examples include methyl, ethyl, propyl, hexyl, and decyl.

[0073]

[0074] In equation (20), R 26 This refers to a hydrogen atom or an alkyl group. 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. Specifically, examples include methyl, ethyl, propyl, hexyl, and decyl.

[0075] Examples of groups represented by formula (19) include vinylbenzyl (ethylene benzyl) as shown in formula (21) below. Furthermore, examples of groups represented by formula (20) include acryloyl and methacryloyl.

[0076]

[0077] More specifically, examples of substituents include: vinylbenzyl (ethylene benzyl) such as o-vinylbenzyl, m-vinylbenzyl, and p-vinylbenzyl; vinylphenyl; acryloyl; and methacryloyl. The polyphenylene ether compound may be a polyphenylene ether compound having one of the aforementioned substituents, or a polyphenylene ether compound having two or more of them. The polyphenylene ether compound may be a polyphenylene ether compound having, for example, any one of o-vinylbenzyl, m-vinylbenzyl, and p-vinylbenzyl, or a polyphenylene ether compound having two or three of them.

[0078] The polyphenylene ether compound has a polyphenylene ether chain in the molecule, preferably having a repeating unit as shown in the following formula (22).

[0079]

[0080] In equation (22), t represents 1 to 50. Furthermore, R 27 ~R 30 Each is independent. That is, R 27 ~R 30 They can be the same group or different groups. Furthermore, R... 27 ~R 30 It represents a hydrogen atom, alkyl, alkenyl, alkynyl, formyl, alkylcarbonyl, alkenylcarbonyl, or alkynylcarbonyl. Among these, hydrogen atoms and alkyl groups are preferred.

[0081] R 27 ~R 30 In this context, the functional groups listed are specifically the following groups.

[0082] 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. Specifically, examples include methyl, ethyl, propyl, hexyl, and decyl.

[0083] The alkenyl group is not particularly limited, but is preferably an alkenyl group with 2 to 18 carbon atoms, and more preferably an alkenyl group with 2 to 10 carbon atoms. Specifically, examples include vinyl, allyl, and 3-butenyl.

[0084] The alkynyl group is not particularly limited, but is preferably an alkynyl group with 2 to 18 carbon atoms, and more preferably an alkynyl group with 2 to 10 carbon atoms. Specifically, examples include ethynyl and prop-2-yn-1-yl (propynyl).

[0085] The alkyl carbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkyl group. For example, it is preferably an alkyl carbonyl group with 2 to 18 carbon atoms, and more preferably an alkyl carbonyl group with 2 to 10 carbon atoms. Specifically, examples include acetyl, propionyl, butyryl, isobutyryl, neopentyl, hexanoyl, octanoyl, and cyclohexyl carbonyl.

[0086] The alkenyl carbonyl group is not particularly limited as long as it is a carbonyl group that has been substituted with an alkenyl group. For example, an alkenyl carbonyl group with 3 to 18 carbon atoms is preferred, and an alkenyl carbonyl group with 3 to 10 carbon atoms is more preferred. Specifically, examples include acryloyl, methacryl, and crotonyl.

[0087] The alkynyl carbonyl group is not particularly limited as long as it is a carbonyl group substituted with an alkynyl group. For example, an alkynyl carbonyl group with 3 to 18 carbon atoms is preferred, and an alkynyl carbonyl group with 3 to 10 carbon atoms is more preferred. Specifically, examples include propynyl groups, etc.

[0088] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polyphenylene ether compound are not particularly limited. Specifically, they are preferably 500 to 5000, more preferably 800 to 4000, and even more preferably 1000 to 3000. It should be noted that the weight-average molecular weight and number-average molecular weight can be values ​​obtained by conventional molecular weight determination methods, such as values ​​obtained by gel permeation chromatography (GPC). Furthermore, when the polyphenylene ether compound has repeating units as shown in formula (22) within its molecule, t is preferably a value that makes the weight-average molecular weight and number-average molecular weight of the polyphenylene ether compound fall within the above-mentioned ranges. Specifically, t is preferably 1 to 50.

[0089] If the weight-average molecular weight and number-average molecular weight of the polyphenylene ether compound are within the above-mentioned range, the polyphenylene ether compound not only possesses the excellent low dielectric properties inherent in polyphenylene ether, but also exhibits superior heat resistance and formability of the cured product. This is believed to be based on the following reasons. In conventional polyphenylene ethers, if their weight-average molecular weight and number-average molecular weight are within the above-mentioned range, the molecular weight is relatively low, thus tending to reduce heat resistance. Regarding this point, it is believed that since the polyphenylene ether compound involved in this embodiment has one or more unsaturated double bonds at the ends, the cured product can obtain sufficiently high heat resistance through the progress of the curing reaction. Furthermore, it is believed that if the weight-average molecular weight and number-average molecular weight of the polyphenylene ether compound are within the above-mentioned range, the formability is also excellent because the molecular weight is relatively low. Therefore, it is believed that this polyphenylene ether compound can achieve the effect of not only superior heat resistance of the cured product, but also excellent formability.

[0090] The average number of substituents (terminal functional groups) at the end of each molecule of the polyphenylene ether compound is not particularly limited. Specifically, it is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1.5 to 3. If the number of terminal functional groups is too small, it tends to be difficult to obtain a cured product with sufficient heat resistance. In addition, if the number of terminal functional groups is too large, the reactivity becomes too high, and there is a risk of adverse conditions such as reduced shelf life of the resin composition or reduced flowability of the resin composition. That is, if this polyphenylene ether compound is used, moldability problems may occur due to insufficient flowability, for example, forming defects such as voids during multilayer molding, making it difficult to obtain a highly reliable printed wiring board.

[0091] It should be noted that the number of terminal functional groups in a polyphenylene ether compound can be exemplified by a numerical value representing the average number of substituents in each molecule of all polyphenylene ether compounds present in 1 mole of the compound. This number of terminal functional groups can be determined, for example, by measuring the number of residual hydroxyl groups in the resulting polyphenylene ether compound and calculating the reduction in the number of hydroxyl groups compared to the polyphenylene ether before modification. This reduction in the number of hydroxyl groups compared to the polyphenylene ether before modification is the number of terminal functional groups. Furthermore, the number of residual hydroxyl groups in the polyphenylene ether compound can be determined by adding a quaternary ammonium salt (tetraethylammonium hydroxide) associated with hydroxyl groups to a solution of the polyphenylene ether compound and measuring the UV absorbance of the mixed solution.

[0092] The intrinsic viscosity of the polyphenylene ether compound is not particularly limited. Specifically, it is acceptable to have a viscosity of 0.03 to 0.12 dl / g, but preferably 0.04 to 0.11 dl / g, and more preferably 0.06 to 0.095 dl / g. If the intrinsic viscosity is too low, there is a tendency for a low molecular weight, and it is difficult to obtain low dielectric properties such as a low relative permittivity and a low dielectric loss factor. Furthermore, if the intrinsic viscosity is too high, the viscosity is high, making it difficult to obtain sufficient flowability, and there is a tendency for reduced formability of the cured product. Therefore, if the intrinsic viscosity of the polyphenylene ether compound is within the above range, excellent heat resistance and formability of the cured product can be achieved.

[0093] It should be noted that the intrinsic viscosity here refers to the intrinsic viscosity measured in dichloromethane at 25°C. More specifically, it is the value obtained by measuring a 0.18 g / 45 ml dichloromethane solution (liquid temperature 25°C) using a viscometer. Examples of such viscometers include the AVS500 Visco System manufactured by Schott.

[0094] Examples of the polyphenylene ether compounds include those shown in formula (23) and those shown in formula (24). Furthermore, these polyphenylene ether compounds can be used alone or in combination.

[0095]

[0096]

[0097] In equations (23) and (24), R 31 ~R 38 and R 39 ~R 42 Each is independent. That is, R 31 ~R 38 and R 39 ~R 42They can be the same group or different groups. Furthermore, R... 31 ~R 38 and R 39 ~R 42 The group represents a hydrogen atom, alkyl, alkenyl, alkynyl, formyl, alkylcarbonyl, alkenylcarbonyl, or alkynylcarbonyl. X1 and X2 are independent. That is, X1 and X2 can be the same group or different groups. X1 and X2 represent substituents having carbon-carbon unsaturated double bonds. A and B represent repeating units shown in formula (25) and formula (26) below, respectively. In addition, in formula (24), Y represents a straight-chain, branched, or cyclic hydrocarbon with 20 or fewer carbon atoms.

[0098]

[0099]

[0100] In equations (25) and (26), m and n represent 0 to 20, respectively. 47 ~R 50 and R 51 ~R 54 Each is independent. That is, R 47 ~R 50 and R 51 ~R 54 They can be the same group or different groups. Furthermore, R... 47 ~R 50 and R 51 ~R 54 It represents a hydrogen atom, alkyl, alkenyl, alkynyl, formyl, alkyl carbonyl, alkenyl carbonyl, or alkynyl carbonyl.

[0101] The polyphenylene ether compounds represented by formula (23) and formula (24) are not particularly limited as long as they satisfy the above-described composition. Specifically, in formulas (23) and (24), as described above, R 31 ~R 38 and R 39 ~R 42 Each is independent. That is, R 31 ~R 38 and R 39 ~R 42 They can be the same group or different groups. Furthermore, R... 31 ~R 38 and R 39 ~R 42 It represents a hydrogen atom, alkyl, alkenyl, alkynyl, formyl, alkylcarbonyl, alkenylcarbonyl, or alkynylcarbonyl. Among these, hydrogen atoms and alkyl groups are preferred.

[0102] In equations (25) and (26), m and n are preferably represented as 0 to 20, as described above. Furthermore, the sum of m and n is preferably represented as a value between 1 and 30. Therefore, more preferably, m represents 0 to 20, n represents 0 to 20, and the sum of m and n represents 1 to 30. Furthermore, R 47 ~R 50 and R 51 ~R 54 Each is independent. That is, R 47 ~R 50 and R 51 ~R 54 They can be the same group or different groups. Furthermore, R... 47 ~R 50 and R 51 ~R 54 It represents a hydrogen atom, alkyl, alkenyl, alkynyl, formyl, alkylcarbonyl, alkenylcarbonyl, or alkynylcarbonyl. Among these, hydrogen atoms and alkyl groups are preferred.

[0103] R 31 ~R 54 R in equation (22) above 27 ~R 30 same.

[0104] In formula (24), as described above, Y is a straight-chain, branched, or cyclic hydrocarbon with 20 or fewer carbon atoms. Examples of Y include groups such as those shown in formula (27) below.

[0105]

[0106] In the above equation (27), R 55 and R 56 Each can be represented independently as a hydrogen atom or an alkyl group. Examples of alkyl groups include, for example, methyl. In addition, examples of groups represented by formula (27) include, for example, methylene, methylmethylene and dimethylmethylene, wherein, dimethylmethylene is preferred.

[0107] In formulas (23) and (24), X1 and X2 are each independently a substituent having a carbon-carbon double bond. It should be noted that in the polyphenylene ether compound shown in formula (23) and the polyphenylene ether compound shown in formula (24), X1 and X2 can be the same group or different groups.

[0108] As a more specific example of the polyphenylene ether compound represented by formula (23), examples such as the polyphenylene ether compound represented by formula (28) below can be cited.

[0109]

[0110] As more specific examples of the polyphenylene ether compounds represented by formula (24), examples include the polyphenylene ether compounds represented by formula (29) below and the polyphenylene ether compounds represented by formula (30) below.

[0111]

[0112]

[0113] In equations (28) to (30) above, m and n are the same as m and n in equations (25) and (26) above. Furthermore, in equations (28) and (29) above, R... 23 ~R 25 p and Ar are related to R in the above formula (19). 23 ~R 25 p and Ar are the same. Furthermore, in equations (29) and (30) above, Y is the same as Y in equation (24) above. Furthermore, in equation (30) above, R... 26 R in equation (20) above 26 same.

[0114] The method for synthesizing the polyphenylene ether compound used in this embodiment is not particularly limited as long as it can synthesize a polyphenylene ether compound having carbon-carbon unsaturated double bonds within the molecule. Specifically, examples of this method include reacting polyphenylene ether with a compound having substituents and halogen atoms bonded with carbon-carbon unsaturated double bonds.

[0115] Examples of compounds having substituents and halogen atoms bonded with carbon-carbon unsaturated double bonds include, for example, compounds having substituents and halogen atoms as shown in formulas (19) to (21). Specifically, chlorine, bromine, iodine, and fluorine atoms are examples of halogen atoms, with chlorine atoms being preferred. More specifically, examples of compounds having substituents and halogen atoms bonded with carbon-carbon unsaturated double bonds include o-chloromethylstyrene, p-chloromethylstyrene, and m-chloromethylstyrene. These compounds having substituents and halogen atoms bonded with carbon-carbon unsaturated double bonds can be used alone or in combination of two or more. For example, o-chloromethylstyrene, p-chloromethylstyrene, and m-chloromethylstyrene can be used alone or in combination of two or three.

[0116] The polyphenylene ether used as a raw material is not particularly limited as long as it can ultimately synthesize the specified polyphenylene ether compound. Specifically, examples include compounds whose main component is a polyphenylene ether containing "2,6-dimethylphenol" and "at least one of bifunctional and trifunctional phenols," or poly(2,6-dimethyl-1,4-phenylene ether). Furthermore, a bifunctional phenol is a phenolic compound having two phenolic hydroxyl groups within its molecule, such as tetramethylbisphenol A. A trifunctional phenol is a phenolic compound having three phenolic hydroxyl groups within its molecule.

[0117] The methods described above can be used to synthesize polyphenylene ether compounds. Specifically, the polyphenylene ether as described above is dissolved in a solvent with the compound having substituents with carbon-carbon unsaturated double bonds and halogen atoms, and the mixture is stirred. Thus, the polyphenylene ether reacts with the compound having substituents with carbon-carbon unsaturated double bonds and halogen atoms to obtain the polyphenylene ether compound used in this embodiment.

[0118] The reaction is preferably carried out in the presence of an alkali metal hydroxide. It is believed that this operation ensures the reaction proceeds well. The reason for this is that the alkali metal hydroxide acts as a dehydrohalogenating agent, specifically as a dehydrochlorinating agent. That is, it is believed that the alkali metal hydroxide causes hydrogen halide to decouple from the phenolic group of the polyphenylene ether from the substituents and halogen atoms bonded to it, thereby allowing the substituents with carbon-carbon unsaturated double bonds to replace the hydrogen atoms of the phenolic group in the polyphenylene ether and bond to the oxygen atoms of the phenolic group.

[0119] Alkali metal hydroxides are not particularly limited in their application as long as they can function as dehalogenating agents; examples include sodium hydroxide. Furthermore, alkali metal hydroxides are typically used in aqueous solutions, specifically as an aqueous solution of sodium hydroxide.

[0120] The reaction time and temperature, among other reaction conditions, vary depending on the compound having substituents with carbon-carbon unsaturated double bonds and halogen atoms, but are not particularly limited as long as the conditions allow the reaction described above to proceed well. Specifically, the reaction temperature is preferably room temperature to 100°C, more preferably 30 to 100°C. Furthermore, the reaction time is preferably 0.5 to 20 hours, more preferably 0.5 to 10 hours.

[0121] The solvent used in the reaction is not particularly limited, as long as it can dissolve the polyphenylene ether in relation to the compound having substituents and halogen atoms bonded with carbon-carbon unsaturated double bonds, and does not hinder the reaction between the polyphenylene ether and the compound having substituents and halogen atoms bonded with carbon-carbon unsaturated double bonds. Specifically, toluene, etc., can be cited as an example.

[0122] It is preferable to carry out the above reaction in the presence of both an alkali metal hydroxide and a phase transfer catalyst. That is, it is preferable to carry out the above reaction in the presence of both an alkali metal hydroxide and a phase transfer catalyst. This operation is believed to facilitate the reaction. This is based on the following reasoning: The phase transfer catalyst is a catalyst that has the function of introducing an alkali metal hydroxide, is soluble in both a polar solvent phase such as water and a non-polar solvent phase such as an organic solvent, and is capable of moving between these phases. Specifically, it is believed that when an aqueous sodium hydroxide solution is used as the alkali metal hydroxide and an organic solvent such as toluene, which is incompatible with water, is used as the solvent, even if the aqueous sodium hydroxide solution is added dropwise to the solvent used for the reaction, the solvent and the aqueous sodium hydroxide solution will separate, and the sodium hydroxide is difficult to migrate into the solvent. Therefore, it is believed that the aqueous sodium hydroxide solution added as an alkali metal hydroxide is unlikely to help promote the reaction. In contrast, it is believed that if the reaction is carried out in the presence of both an alkali metal hydroxide and a phase transfer catalyst, the alkali metal hydroxide will migrate into the solvent under the condition of being introduced by the phase transfer catalyst, and the aqueous sodium hydroxide solution becomes more likely to help promote the reaction. Therefore, it is believed that the above reaction will proceed more smoothly in the presence of alkali metal hydroxides and phase transfer catalysts.

[0123] There are no particular limitations on phase transfer catalysts; examples include quaternary ammonium salts such as tetra-n-butylammonium bromide.

[0124] The resin composition used in this embodiment preferably comprises: the polyphenylene ether compound obtained as described above, as the polyphenylene ether compound.

[0125] (maleimide compound)

[0126] The maleimide compound is not particularly limited to any maleimide compound having a maleimide group within its molecule. Examples of such maleimide compounds include those having an arylene structure oriented and bonded at the meta position, those having an indane structure, and those having both an arylene structure and an indane structure oriented and bonded at the meta position. The maleimide compound may contain any one or two of these compounds.

[0127] The maleimide compound having an intramolecularly oriented aryl group structure is not particularly limited as long as it has the aryl group structure intramolecularly. Examples of the aryl group structure include aryl groups containing a maleimide group bonded at the meta position (aryl groups containing a maleimide group substituted at the meta position). The aryl group is not particularly limited as long as it is oriented at the meta position; examples include meta-phenylene and meta-naphthylene, etc. Commercially available products can also be used as the maleimide compound having an intramolecularly oriented aryl group structure, such as the solid component of MIR-5000-60T manufactured by Nippon Kayaku Co., Ltd.

[0128] The maleimide compound having an indane structure within the molecule is not particularly limited to any maleimide compound having an indane structure within the molecule. Examples of the indane structure include, for instance, a divalent group from which two hydrogen atoms have been removed from an indane or an indane compound substituted with a substituent. It should be noted that the maleimide compound having an indane structure within the molecule also contains a maleimide group within the molecule.

[0129] Specifically, the method for producing the maleimide compound having an intramolecular indane structure can include methods such as the so-called maleimide reaction, which involves reacting an amine compound and maleic anhydride in an organic solvent such as toluene in the presence of a catalyst such as toluenesulfonic acid. Specifically, after this maleimide reaction, unreacted maleic anhydride and other impurities are removed by washing with water, and the solvent is removed under reduced pressure to obtain the maleimide compound having the intramolecular indane structure. A dehydrating agent can also be used in this reaction. It should be noted that commercially available products can also be used as the maleimide compound having the intramolecular indane structure.

[0130] Examples of maleimide compounds having a meta-oriented and bonded arylene structure and an indane structure within the molecule include maleimide compounds having the arylene structure and the indane structure within the molecule.

[0131] The maleimide compound may also be, for example, a maleimide compound other than the maleimide compound having an intramolecularly oriented aryl group bonded in the meta position, the maleimide compound having an intramolecularly indane structure, and the maleimide compound having an intramolecularly oriented aryl group bonded in the meta position and an indane structure (other maleimide compounds). These other maleimide compounds are maleimide compounds having a maleimide group intramolecularly but not having an intramolecularly oriented aryl group bonded in the meta position or an indane structure. Examples include maleimide compounds having one or more maleimide groups intramolecularly, and modified maleimide compounds. Other maleimide compounds mentioned above include, for example, 4,4'-diphenylmethane bismaleimide, polyphenylmethane maleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, biphenyl aryl alkyl polymaleimide compounds, and other phenyl maleimide compounds; as well as N-alkyl bismaleimide compounds having an aliphatic backbone. Modified maleimide compounds include, for example, modified maleimide compounds in which a portion of the molecule is modified by an amine compound, and modified maleimide compounds in which a portion of the molecule is modified by an organosilicon compound. Other maleimide compounds may also be commercially available, such as BMI-4000 and BMI-5100 manufactured by Daiwa Chemical Industries, Ltd., and BMI-689, BMI-1500, and BMI-3000J manufactured by DesignerMolecules Inc.

[0132] The maleimide compound can be used alone or in combination of two or more.

[0133] (hydrocarbon compounds)

[0134] The hydrocarbon compound is not particularly limited as long as it is a thermosetting hydrocarbon compound. Examples of such hydrocarbon compounds include, for example, hydrocarbon compounds represented by the following formula (31).

[0135]

[0136] In formula (31), Z represents a hydrocarbon group with 6 or more carbon atoms and includes at least one of aromatic cyclic groups and aliphatic cyclic groups. a represents 1 to 10.

[0137] The aromatic cyclic group is not particularly limited, and examples include phenylene group, xylylene group, naphthylene group, tolylene group, and biphenylene group. The aliphatic cyclic group is not particularly limited, and examples include groups containing indenhydride structures and groups containing cycloolefin structures. Z is preferably the aromatic cyclic group, and more preferably xylylene. The hydrocarbon group has no particular limitation on the number of carbon atoms as long as it has 6 or more, and is preferably 6 to 20.

[0138] More specifically, examples of hydrocarbon compounds represented by formula (31) include hydrocarbon compounds represented by formula (32) below. Furthermore, the hydrocarbon compounds preferably include hydrocarbon compounds represented by formula (32) below.

[0139]

[0140] In equation (32), n represents 1 to 10.

[0141] Examples of such hydrocarbon compounds include, for example, divinyl aromatic compounds and aromatic polymers having structural units derived from difunctional aromatic compounds having two carbon-carbon unsaturated double bonds bonded to an aromatic ring. It should be noted that the structural units derived from the difunctional aromatic compounds are structural units obtained by polymerizing the difunctional aromatic compounds. Examples of such difunctional aromatic compounds include, for example, divinylbenzene such as m-divinylbenzene and p-divinylbenzene, more preferably p-divinylbenzene. The aromatic polymers may have structural units not only derived from the difunctional aromatic compounds but also other structural units. Examples of such other structural units include, for example, monovinyl aromatic compounds having structural units derived from monofunctional aromatic compounds having one carbon-carbon unsaturated double bond bonded to an aromatic ring. Examples of such monovinyl aromatic compounds include, for example, ethylvinyl aromatic compounds. It should be noted that the structural units derived from the monofunctional aromatic compounds are structural units obtained by polymerizing the monofunctional aromatic compounds. The aromatic polymer, when it has not only structural units derived from the difunctional aromatic compound but also other structural units, is a copolymer of structural units derived from the difunctional aromatic compound and other structural units such as structural units derived from the monofunctional aromatic compound. This copolymer can be a block copolymer or a random copolymer. Examples of the hydrocarbon compounds mentioned above include the aromatic polymers, such as polyfunctional vinyl aromatic copolymers. Examples of polyfunctional vinyl aromatic copolymers include copolymers having repeating units (a) derived from divinyl aromatic compounds and repeating units (b) derived from monovinyl aromatic compounds. The content of repeating units (a) and repeating units (b) in the polyfunctional vinyl aromatic copolymer is not particularly limited; however, when the total of repeating units (a) and repeating units (b) is 100 mol%, it is preferable to contain 2 mol% or more and less than 95 mol% of repeating units (a) and 5 mol% or more and less than 98 mol% of repeating units (b). Furthermore, the molecular weight of the polyfunctional vinyl aromatic copolymer is not particularly limited, but is preferably 300 to 10,000 in terms of number average molecular weight (Mn). Examples of such polyfunctional vinyl aromatic copolymers include the one described in Japanese Patent Publication No. 2018-168347. Additionally, the hydrocarbon compound preferably comprises at least one of the polyfunctional vinyl aromatic copolymer and the hydrocarbon compound represented by formula (31).

[0142] (Curing agent)

[0143] As described above, the resin composition may also contain a curing agent that reacts with the curable compound, if necessary. Here, a curing agent refers to a compound that reacts with the curable compound to facilitate the curing of the resin composition. Examples of curing agents include epoxy compounds, methacrylate compounds, acrylate compounds, vinyl compounds, cyanate compounds, reactive ester compounds, and allyl compounds.

[0144] The epoxy compound is a compound having an epoxy group within its molecule. Specifically, examples include: bisphenol-type epoxy compounds such as bisphenol A type epoxy compounds, phenolic aldehyde-type epoxy compounds, cresol aldehyde-type epoxy compounds, dicyclopentadiene-type epoxy compounds, bisphenol A aldehyde-type epoxy compounds, biphenyl aryl-type epoxy compounds, and epoxy compounds containing a naphthalene ring. Furthermore, the epoxy compound also includes epoxy resins that are polymers of each of the aforementioned epoxy compounds.

[0145] The methacrylate compound is a compound having a methacryl group within its molecule. Examples include monofunctional methacrylate compounds having one methacryl group within their molecule, and polyfunctional methacrylate compounds having two or more methacryl groups within their molecule. Examples of monofunctional methacrylate compounds include methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate. Examples of polyfunctional methacrylate compounds include dimethacrylate compounds such as tricyclodecanediethanol dimethacrylate (DCP).

[0146] The acrylate compound is a compound having an acryloyl group within its molecule. Examples include monofunctional acrylate compounds having one acryloyl group within their molecule, and polyfunctional acrylate compounds having two or more acryloyl groups within their molecule. Examples of monofunctional acrylate compounds include methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate. Examples of polyfunctional acrylate compounds include diacrylate compounds such as tricyclodecanediethanol diacrylate.

[0147] The vinyl compound is a compound having a vinyl group within its molecule. Examples include monofunctional vinyl compounds having one vinyl group within their molecule, and polyfunctional vinyl compounds having two or more vinyl groups within their molecule. Examples of such polyfunctional vinyl compounds include divinylbenzene, curable polybutadiene having a carbon-carbon unsaturated double bond within its molecule, and curable butadiene-styrene copolymer having a carbon-carbon unsaturated double bond within its molecule.

[0148] The cyanate ester compound is a compound having a cyanato group in the molecule, and examples include 2,2-bis(4-cyanooxyphenyl)propane, bis(3,5-dimethyl-4-cyanooxyphenyl)methane, and 2,2-bis(4-cyanooxyphenyl)ethane.

[0149] The active ester compound is a compound with a highly reactive ester group within the molecule, and examples include: benzenecarboxylic acid active ester, benzenedicarboxylic acid active ester, benzenetricarboxylicacid active ester, benzenetetracarboxylic acid active ester, naphthalenecarboxylic acid active ester, naphthalenedicarboxylic acid active ester, naphthalenetricarboxylic acid active ester, naphthalenetetracarboxylic acid active ester, fluorenecarboxylic acid active ester, fluorenedicarboxylicacid active ester, fluorenetricarboxylic acid active ester, and fluorenetetracarboxylic acid active ester. ester), etc.

[0150] The allyl compound is a compound having an allyl group in its molecule, and examples include: triallyl isocyanurate compounds such as triallyl isocyanurate (TAIC), diallyl bisphenol compounds, and diallyl phthalate (DAP), etc.

[0151] Regarding the curing agent, it can be used alone or in combination of two or more.

[0152] The weight-average molecular weight of the curing agent is not particularly limited, but is preferably 100 to 5000, more preferably 100 to 4000, and even more preferably 100 to 3000. If the weight-average molecular weight of the curing agent is too low, there is a risk that the curing agent may easily volatilize from the compounding system of the resin composition. Furthermore, if the weight-average molecular weight of the curing agent is too high, there is a risk that the viscosity of the varnish of the resin composition, the melt viscosity when the resin composition is made into grade B, becomes too high, resulting in poor formability and a poor appearance after molding. Therefore, if the weight-average molecular weight of the curing agent is within this range, a resin composition with better heat resistance and formability can be obtained. This is believed to be because the resin composition can be cured well. It should be noted that here, the weight-average molecular weight can be any value obtained by a conventional molecular weight determination method, such as a value obtained by gel permeation chromatography (GPC).

[0153] Regarding the curing agent, the average number of functional groups (functional group number) in each molecule of the curing agent that contribute to the reaction during the curing of the resin composition varies depending on the weight-average molecular weight of the curing agent, and is preferably 1 to 20, more preferably 2 to 18. If the number of functional groups is too small, it tends to be difficult to obtain a cured product with sufficient heat resistance. Furthermore, if the number of functional groups is too large, the reactivity becomes too high, which may lead to adverse conditions such as reduced shelf life of the resin composition or reduced flowability of the resin composition.

[0154] (content)

[0155] The content of the elastomer relative to the resin composition is preferably greater than 10% by mass, more preferably greater than 10% by mass and less than 40% by mass, and even more preferably 15 to 35% by mass. The content of the curable compound relative to the resin composition is preferably less than 80% by mass, more preferably more than 20% by mass and less than 80% by mass, and even more preferably 30 to 70% by mass. If the contents of the elastomer and the curable compound are within the above ranges, a cured product with a low relative permittivity (e.g., a relative permittivity of less than 2.6 at 10 GHz) can be obtained.

[0156] (Other ingredients)

[0157] The resin composition may, as needed and without impairing the effects of the present invention, contain components other than the filler, the elastomer, and the curable compound (other components). Other components of the resin composition may include, for example, reaction initiators, reaction promoters, catalysts, polymerization retardants, polymerization inhibitors, dispersants, homogenizers, silane coupling agents, defoamers, antioxidants, heat stabilizers, antistatic agents, ultraviolet absorbers, dyes or pigments, and lubricants.

[0158] As described above, the resin composition may also contain a reaction initiator. The reaction initiator is not particularly limited as long as it can promote the curing reaction of the resin composition; examples include peroxides and organic azo compounds. Examples of peroxides include α,α'-bis(tert-butylperoxym-isopropyl)benzene, 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, and benzoyl peroxide. Examples of organic azo compounds include azobisisobutyronitrile. Furthermore, metal carboxylic acid salts may be used in combination as needed. This further promotes the curing reaction. α,α'-bis(tert-butylperoxym-isopropyl)benzene is preferred. Because α,α'-bis(tert-butylperoxym-isopropyl)benzene has a relatively high reaction initiation temperature, it can suppress the promotion of the curing reaction during prepreg drying and other times when curing is not required, thus preventing a decrease in the shelf life of the resin composition. Furthermore, α,α'-bis(tert-butylperoxym-isopropyl)benzene exhibits low volatility and therefore does not volatilize during prepreg drying or storage, demonstrating good stability. In addition, the reaction initiator can be used alone or in combination of two or more.

[0159] As described above, the resin composition may also contain a silane coupling agent. The silane coupling agent may be included in the resin composition or may be included as a silane coupling agent in which the filler material contained in the resin composition has been pre-treated. Preferably, the silane coupling agent is included as a silane coupling agent in which the filler material has been pre-treated; more preferably, it is included in this way, and the resin composition also contains the silane coupling agent. Furthermore, in the case of prepregs, the silane coupling agent may be included as a silane coupling agent in which the fibrous substrate has been pre-treated. Examples of such silane coupling agents include, for instance, the same silane coupling agent used when surface-treating the filler material as described above.

[0160] As described above, the resin composition may also contain a flame retardant. Containing a flame retardant can improve the flame retardancy of the cured resin composition. The flame retardant is not particularly limited. Specifically, in the field of using halogenated flame retardants such as brominated flame retardants, preferred examples include ethylenedipentabromobenzene, ethylenebistetrabromoimide, decabromodiphenyl ether, and tetradecylbromodiphenoxybenzene, which have melting points of 300°C or higher. It is believed that by using halogenated flame retardants, halogen release at high temperatures can be suppressed, thus preventing a decrease in heat resistance. Furthermore, in fields requiring halogen-free properties, phosphorus-containing flame retardants (phosphorus-based flame retardants) are sometimes used. The phosphorus-based flame retardant is not particularly limited, and examples include: phosphate ester-based flame retardants, phosphazene-based flame retardants, phosphine oxide-based flame retardants, and phosphinate-based flame retardants. Specific examples of phosphate ester-based flame retardants include polyphosphate esters of bis(xyl)phosphite. Specific examples of phosphazene-based flame retardants include phenoxyphosphazene. Specific examples of phosphine oxide-based flame retardants include, for example, bis(diphenylphosphine oxide), and specifically, xylenebis(diphenylphosphine oxide). Specific examples of phosphinate-based flame retardants include, for example, dialkyl aluminum hypophosphite metal salts. The flame retardants can be used alone or in combination of two or more.

[0161] (Manufacturing method)

[0162] The method for manufacturing the resin composition is not particularly limited, and examples include: mixing the components constituting the resin composition, such as the filler, the elastomer, and the curable compound, at specified concentrations. The method for manufacturing a cured product of the resin composition is also not particularly limited, and examples include: curing the resin composition by heating it.

[0163] (Dielectric properties)

[0164] The cured resin composition has a relative permittivity of less than 2.6 at 10 GHz, preferably 1 or more and less than 2.4, more preferably 1 or more and less than 2.2. Cured compositions with this relative permittivity can reduce signal transmission losses in conductor wiring (conductor circuits) formed on the cured composition. Furthermore, the dielectric loss factor of the cured resin composition at 10 GHz is preferably 0.005 or less, more preferably 0.0001 to 0.005, and even more preferably 0.0001 to 0.003. It should be noted that the relative permittivity and dielectric loss factor here refer to the relative permittivity and dielectric loss factor of the insulating layer at a frequency of 10 GHz, such as the relative permittivity and dielectric loss factor of the insulating layer at a frequency of 10 GHz measured by the resonant cavity perturbation method.

[0165] (Surface roughness)

[0166] The surface roughness Ra of the cured resin composition is less than 100 nm, preferably 1 nm or more and less than 80 nm, more preferably 1 nm or more and less than 60 nm. If the surface roughness Ra is too high, there is a tendency that the surface roughness Ra cannot be maintained at a low level after plasma treatment. Therefore, if the surface roughness Ra is within the specified range, a cured product with a low surface roughness Ra after plasma treatment can be obtained. It should be noted that Ra is the arithmetic mean height of the roughness curve specified in JIS B0601:2001. Examples of Ra values ​​include those measured using a surface roughness measuring instrument, a laser microscope, and an atomic force microscope, and more specifically, values ​​measured using a scanning confocal laser microscope (LEXT OLS3000 manufactured by Olympus Corporation) for surface roughness analysis.

[0167] (Coefficient of thermal expansion)

[0168] The coefficient of thermal expansion (CTE) of the cured resin composition is preferably less than 80 ppm / °C, more preferably 15–65 ppm / °C, and even more preferably 15–55 ppm / °C. If the CTE is within this range, the rate of dimensional change of the cured resin composition due to heating is relatively small. It should be noted that the coefficient of thermal expansion represents the proportion by which the length of an object expands with increasing temperature (1°C). For example, the CTE measured by the TMA (Thermo-mechanical Analysis) method can be cited. More specifically, the CTE measured by the TMA method in a temperature range of 50–100°C can be cited.

[0169] (Energy storage modulus)

[0170] The storage modulus E' of the cured resin composition is preferably 4 GPa or less, more preferably 0.5 to 3 GPa. If the storage modulus is within this range, the cured resin composition is relatively soft, which can reduce stress applied to wiring boards or semiconductor packages, for example. Examples of storage modulus E' include, for instance, the storage modulus at 40°C when measured using a dynamic viscoelasticity measuring device.

[0171] (Wiring board)

[0172] The cured resin composition according to this embodiment can be used in the manufacture of wiring boards, etc. For example, the cured resin composition according to this embodiment can be used as an insulating layer provided in a wiring board. That is, the wiring board according to other embodiments of the present invention includes: an insulating layer containing the cured product (the cured resin composition); and a wiring board for wiring.

[0173] The method for manufacturing the wiring board is not particularly limited as long as it can produce a wiring board having an insulating layer comprising the cured material and wiring. Specifically, examples of the manufacturing method include... Figure 1 The manufacturing method shown, etc. It should be noted that... Figure 1 This is a schematic diagram illustrating an example of a method for manufacturing a wiring board using a cured material according to this embodiment.

[0174] First, such as Figure 1 As shown in (a), a release film 13 having a resin layer 12 is overlapped onto the support plate 11 such that the resin layer 12 contacts the surface 11a of the support plate 11. Alternatively, the support plate 11 and the resin layer 12 can be sealed together using methods such as vacuum lamination. Thus, as... Figure 1 As shown in (b), the support plate 11 and the resin layer 12 are stacked, and the resin layer 12 is formed on the surface 11a of the support plate 11. It should be noted that, here, the support plate 11 is a metal foil laminate having an insulating layer 112 and a metal foil 111 disposed on the surface of the insulating layer 112, etc., but it is not limited to this.

[0175] Next, as follows Figure 1 (b) The resin layer 12 formed on the surface of the support plate 11, as shown, is cured while the release film 13 is held in place. Alternatively, the resin layer 12 can be cured by vacuum curing (e.g., curing by heating under vacuum) as described above. Thus, as... Figure 1 As shown in (c), an insulating layer 14, formed by curing the resin layer 12, is formed on the support plate 11. Then, as... Figure 1As shown in (c), the release film 13 is peeled off.

[0176] Next, as Figure 1 As shown in (d), the surface 14a of the insulating layer 14 that does not contact the support plate 11 is roughened by plasma treatment.

[0177] Next, by performing a sputtering process on the roughened surface 14a of the insulating layer 14, as shown... Figure 1 As shown in (e), a seed layer 15 is formed on the roughened surface 14a of the insulating layer 14. While the seed layer 15 may include a seed layer body 152 and a seed bonding layer 151 for improving the adhesion between the seed layer body 152 and the insulating layer 14, it is not limited to this. Examples of the seed bonding layer 151 include, for example, a Ti layer. Examples of the seed layer body 152 include, for example, a Cu layer.

[0178] Next, as Figure 1 As shown in (f), the seed layer 15 is used to form the conductor layer 16. Specifically, by performing an electroplating process on the seed layer 15, a conductor layer 16 integrated with the seed layer body 152 can be formed. This conductor layer 16 can be formed as a conductor wiring pattern.

[0179] In this manufacturing method, the resin layer 12 is a layer containing the resin composition (e.g., a layer formed from the resin composition). Since the resin layer 12 is a layer containing the resin composition, the insulating layer 14 obtained by curing the resin layer 12 is a layer containing a cured product of the resin composition (e.g., a layer formed from a cured product of the resin composition). Therefore, this manufacturing method uses a cured product of the resin composition to manufacture a wiring board. As described above, the surface roughness Ra of the cured product of the resin composition before plasma treatment is less than 100 nm. Furthermore, even after plasma treatment, the surface roughness Ra of the cured product of the resin composition remains, for example, less than 100 nm, maintaining a low surface roughness Ra. In addition, the relative permittivity of the cured product of the resin composition at 10 GHz is less than 2.6, i.e., low. For these reasons, when a conductor wiring pattern is formed as a conductor layer 16 formed on the cured product, signal transmission losses in the conductor wiring (conductor circuit) can be reduced.

[0180] As a manufacturing method, in the case of forming a conductor wiring pattern, examples include: Figure 2 The manufacturing method shown, etc. It should be noted that... Figure 2 This is a schematic diagram illustrating another example of the method for manufacturing a wiring board using a cured material according to this embodiment.

[0181] First, such as Figure 2 As shown in (a), a release film 13 having a resin layer 12 is overlapped onto the support plate 11 in such a way that the resin layer 12 contacts the surface 11a of the support plate 11, thereby achieving the following: Figure 2 As shown in (b), the resin layer 12 is formed on the surface of the support plate 11.

[0182] Next, as follows Figure 2 (b) The resin layer 12 formed on the surface of the support plate 11 is cured while the release film 13 is attached. As a result, an insulating layer 14 formed by curing the resin layer 12 is formed on the surface of the support plate 11.

[0183] Next, while the release film 13 is attached, the insulating layer 14, formed by curing the resin layer 12, is laser-processed to create recesses 22 in the insulating layer 14. These recesses 22 correspond to the conductor wiring pattern to be formed. The laser processing is not particularly limited as long as it can form recesses corresponding to the conductor wiring pattern on the insulating layer 14; examples include CO2 lasers and UV lasers. Then, the recesses 22 formed in the insulating layer 14 are subjected to plasma descaling. This removes the residue (adhesive residue) from the insulating layer 14 generated during the laser processing from the recesses 22. The plasma descaling is not particularly limited as long as it can utilize plasma descaling; examples include processes similar to the plasma treatment described later. Here, plasma treatment using a mixture of oxygen and carbon tetrafluoride is preferred (surface treatment using plasma generated from a mixture of oxygen and carbon tetrafluoride as the raw material gas).

[0184] Next, as Figure 2 As shown in (d), the release film 13 is peeled off from the insulating layer 14 where the recess 22 is formed. Next, the surface 14a of the insulating layer 14 that does not contact the support plate 11 is roughened by performing the plasma treatment.

[0185] Next, by performing a sputtering process on the roughened surface 14a of the insulating layer 14, as shown... Figure 2 As shown in (e), a seed layer 15 is formed on the roughened surface 14a of the insulating layer 14.

[0186] Next, as Figure 2As shown in (f), a photoresist layer 18 is formed on the insulating layer 14 on which the seed layer 15 is formed. Then, as... Figure 2 As shown in (g), the photoresist layer 18 is selectively exposed for development in a manner that leaves the photoresist layer 18 in the area where the conductor layer 19 is to be formed (corresponding to the area where the final conductor wiring pattern will be formed). Next, as... Figure 2 As shown in (h), the conductor layer 19 is formed using the seed layer 15. Specifically, by performing an electroplating process using the seed layer 15, a conductor layer 19 integral with the seed layer 15 can be formed. Then, as... Figure 2 As shown in (i), the photoresist layer 18 is peeled off. Then, as... Figure 2 As shown in (j), the conductor wiring pattern 20 is formed by etching away a portion of the seed layer 15 in the conductor layer 19. Finally, as Figure 2 As shown in (k), the conductor wiring pattern 20 can be covered with other insulating layers 31.

[0187] The manufacturing method described above can also form conductor wiring patterns on the opposite side of the support plate from the side where the conductor wiring pattern is formed, using the same method as described above. That is, the manufacturing method can form conductor wiring patterns on one side of the support plate, or it can form conductor wiring patterns on both sides. Furthermore, when conductor wiring patterns are formed on both sides, they can be formed simultaneously on both sides, or they can be formed at different times.

[0188] In this manufacturing method, the resin layer 12 is also a layer containing the resin composition (e.g., a layer formed from the resin composition). Since the resin layer 12 is a layer containing the resin composition, the insulating layer 14 obtained by curing the resin layer 12 is a layer containing a cured resin composition (e.g., a layer formed from a cured resin composition). Therefore, this manufacturing method is also a method of manufacturing a wiring board using a cured resin composition. As described above, the surface roughness Ra of the cured resin composition before plasma treatment is less than 100 nm. Furthermore, even after plasma treatment, the surface roughness Ra of the cured resin composition remains, for example, less than 100 nm, maintaining a low surface roughness Ra. In addition, the relative permittivity of the cured resin composition at 10 GHz is less than 2.6, i.e., low. For these reasons, signal transmission loss during the conductor wiring pattern 20 formed on the cured material can be reduced. Furthermore, by repeatedly performing this manufacturing method, a wiring board with multiple layers of the conductor wiring pattern 20 can be manufactured.

[0189] Based on the above description, the method for manufacturing a wiring board using a cured resin composition according to this embodiment can include the following wiring board manufacturing method, which includes: a step (A) of forming an insulating layer formed by curing a resin layer that is in contact with one side surface of a support plate; a step (B) of roughening the side surface of the insulating layer that is not in contact with the support plate by plasma treatment; and a step (C) of forming a seed layer on the roughened surface of the insulating layer by sputtering treatment, wherein the insulating layer 14 is a layer formed by the cured resin composition. The manufacturing method may also include a step (D) of forming a conductor wiring pattern on the seed layer. Furthermore, the wiring board can also be made into a semiconductor package by mounting a semiconductor chip. That is, the semiconductor package according to other embodiments of the present invention includes: the wiring board; and a semiconductor package with a semiconductor chip mounted on the wiring board. Examples of such semiconductor packages include, for example, semiconductor packages that connect the semiconductor chip to conductor wiring (conductor circuit) in the conductor wiring pattern.

[0190] Step (A) is not particularly limited as long as it can form an insulating layer by curing a resin layer formed in a manner that contacts at least one side surface of the support plate. The resin layer is not particularly limited as long as it contains the resin composition; examples include layers formed from the resin composition. Furthermore, the insulating layer is not particularly limited as long as it contains a cured product of the resin composition; examples include layers formed from a cured product of the resin composition.

[0191] Methods for forming the resin layer include, for example, coating a resin composition onto a support plate (coating method) and laminating a resin film onto the support plate (lamination method). Specifically, the coating method involves coating a fluid resin composition (resin varnish, resin solution, etc.) onto the support plate and drying the coated resin composition to form the resin layer on the support plate. Furthermore, the lamination method involves laminating a resin film, which will become the resin layer, onto the support plate. More specifically, this method involves laminating a resin film laminated on a release film onto the support plate and then peeling the release film off the resin film. Examples of this resin film lamination include, for instance, vacuum lamination. Additionally, the resin film can be formed by coating a fluid resin composition (resin varnish, resin solution, etc.) onto a release film and drying the resin composition coated on the release film.

[0192] The support plate is not particularly limited as long as an insulating layer (an insulating layer with a seed layer) can be formed on its surface. Examples of such supports include resin films, metal foils, metal plates, metal foil-coated laminates, and inner substrates.

[0193] As for the curing method of the resin layer, there is no particular limitation as long as an insulating layer can be formed. Examples of curing methods for the resin layer include, for example, curing under vacuum conditions, i.e., vacuum curing. Furthermore, if the resin layer is thermosetting, methods such as heating the resin layer can be included. As for the curing conditions of the resin layer, there is no particular limitation as long as the conditions are sufficient to cure the resin layer and form the insulating layer. For example, the heating temperature is preferably 80–250°C, more preferably 100–230°C. Furthermore, the heating time is preferably 1–4 hours, more preferably 1.5–3 hours. More specifically, as a method for heating the resin layer, examples include: heating from room temperature to a specified temperature of 80–150°C, holding for about 30 minutes, further heating to a specified temperature of 180–230°C, and holding that specified temperature for 1–4 hours. Furthermore, vacuum curing can also be used as a method for heating the resin layer. Furthermore, as a method for curing the resin layer, if the resin layer is photocurable, methods such as irradiating the resin layer with ultraviolet light can be cited.

[0194] Step (B) is not particularly limited as long as it can roughen the insulating layer through plasma treatment. In step (B), since the insulating layer on the support is subjected to plasma treatment, the surface of the insulating layer opposite to the surface in contact with the support (the surface that is not in contact with the support) is also subjected to plasma treatment. The plasma treatment is not particularly limited, and examples include oxygen plasma treatment (surface treatment using plasma generated by using oxygen as the feed gas), oxygen and carbon tetrafluoride mixed gas plasma treatment (surface treatment using plasma generated by using a mixed gas of oxygen and carbon tetrafluoride as the feed gas), and argon, hydrogen, and nitrogen mixed gas plasma treatment (surface treatment using plasma generated by using a mixed gas of argon, hydrogen, and nitrogen as the feed gas). Among these, oxygen plasma treatment is preferred. Furthermore, these plasma treatments can be used alone or in combination of two or more.

[0195] The conditions for plasma treatment are not particularly limited. The plasma irradiation dose in the plasma treatment, expressed in power density, is preferably 100–500 W / cm². 2The plasma treatment time varies depending on the amount of raw material gas, plasma density, etc., and is preferably 0.5 to 5 minutes.

[0196] The plasma treatment can be performed using microwave plasma (plasma excited by microwaves) or RF (radio frequency) plasma (plasma excited by RF). These plasmas can be pulsed or DC excited. As the microwave, for example, microwaves with frequencies of 1 GHz or higher that are industrially usable and capable of generating high-density non-equilibrium plasma can be used; microwaves with a frequency of 2.45 GHz are preferred. In the case of microwave plasma, the microwave power used to generate the plasma atmosphere can be, for example, 300 W or higher. Furthermore, the RF plasma is a widely used industrial plasma; in Japan, from a legal and regulatory perspective, the excitation frequency used to generate the RF plasma is generally 13.56 MHz.

[0197] Step (C) is not particularly limited as long as it can form a seed layer on the roughened surface of the insulating layer by sputtering. The sputtering process is not particularly limited as long as it can form the seed layer on the roughened surface of the insulating layer.

[0198] Examples of sputtering processes include, for instance, sputtering processes using the metal constituting the seed layer as the target material. Furthermore, examples of sputtering processes include, for instance, sputtering processes performed under vacuum. Specifically, examples of sputtering processes include: placing the metal constituting the seed layer as the target material in a vacuum chamber, and colliding a gas ionized by applying a high voltage with the target material, thereby causing the metal atoms to separate from the target surface and adhere to the roughened surface of the insulating layer to form a film. Examples of gases include rare gases such as argon and nitrogen. Furthermore, examples of sputtering processes include, for instance, processes performed by direct current (DC) sputtering, high-frequency (RF) sputtering, DC magnetron sputtering, RF magnetron sputtering, and ion beam sputtering.

[0199] The seed layer is not particularly limited as long as it is formed on the surface of an insulating layer or the like during the manufacturing of the wiring board. The seed layer serves as an electrode, for example, when a conductor wiring pattern and conductor layer are subsequently formed through electroplating or other processes. That is, when the seed layer undergoes electroplating, it functions as a power supply layer for the electroplating process. Examples of metals contained in the seed layer include titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), copper (Cu), cobalt (Co), aluminum (Al), molybdenum (Mo), tantalum (Ta), iridium (Ir), ruthenium (Ru), lead (Pb), gold (Au), and platinum (Pt), with Ti, Cr, Ni, and W being preferred. This metal can be used alone or in combination of two or more. Specifically, the seed layer preferably contains at least one selected from the group consisting of Ti, Cr, Ni, and W. Furthermore, the seed layer may also include: a seed layer body; and a seed bonding layer for improving the adhesion between the seed layer body and the insulating layer or the like. Examples of seed layers include layers formed by stacking a Ti-containing layer (e.g., a layer formed of Ti) as the seed binding layer and a Cu-containing layer (e.g., a layer formed of Cu) as the main body of the seed layer. The thickness of the seed layer can be, for example, 200–350 nm. Furthermore, when the seed layer comprises the main body of the seed layer and the seed binding layer, the thickness of the main body of the seed layer can be, for example, 150–250 nm, and the thickness of the seed binding layer can be, for example, 50–100 nm.

[0200] As described above, the manufacturing method only requires forming a conductor wiring pattern based on the seed layer. Specifically, it may also include a step (D) of forming a conductor wiring pattern on the seed layer. This step (D) is not particularly limited as long as the seed layer can be used to form a conductor wiring pattern; examples include methods such as forming a wiring layer by electroplating. Examples of electroplating processes include electroplating nickel, electroplating copper, electroplating chromium, electroplating palladium, electroplating gold, electroplating rhodium, and electroplating iridium, with electroplating copper being preferred.

[0201] In the manufacturing method described above, a layer containing a cured resin composition (e.g., a layer formed from a cured resin composition) is used as the insulating layer. Therefore, this manufacturing method is a method of manufacturing a wiring board using a cured resin composition. As described above, the surface roughness Ra of the cured resin composition before plasma treatment is less than 100 nm. Furthermore, even after plasma treatment, the surface roughness Ra of the cured resin composition remains, for example, less than 100 nm, maintaining a low surface roughness Ra. In addition, the relative permittivity of the cured resin composition at 10 GHz is less than 2.6, i.e., low. For these reasons, signal transmission losses in the conductor wiring pattern formed based on the seed layer can be reduced. Specifically, signal transmission losses in the conductor wiring pattern (conductor circuit) formed by performing step (D) can be reduced.

[0202] This specification discloses the techniques of various embodiments as described above, and the main technical features are summarized below.

[0203] The first technical solution of the present invention relates to a cured resin composition containing a filler material, wherein 50% of the particle size D50 in the cumulative particle size distribution of the filler material on a volume basis is less than 2100 nm, the content of the filler material relative to the resin composition is less than 35% by mass, the relative permittivity of the cured product at 10 GHz is less than 2.6, and the surface roughness Ra of the cured product is less than 100 nm.

[0204] In the cured resin composition of the second technical solution of the present invention, the 50% particle size D50 of the cumulative particle size distribution of the filler material in the volume reference of the cured resin composition of the first technical solution of the present invention is 100-700 nm.

[0205] The cured resin composition of the third technical solution of the present invention has a coefficient of thermal expansion of less than 80 ppm / ℃ compared with the cured resin composition of the first or second technical solution of the present invention.

[0206] The cured resin composition of the fourth technical solution of the present invention, in any one of the first to third technical solutions of the present invention, further contains an elastomer, wherein the content of the elastomer is greater than 10 by mass relative to the resin composition.

[0207] The resin composition of the fifth technical solution of the present invention, in any of the resin compositions of the first to fourth technical solutions of the present invention, wherein the filler material comprises at least one selected from the group consisting of polystyrene particles, hollow polystyrene particles, inorganic particles and hollow inorganic particles.

[0208] The sixth technical solution of the present invention relates to a wiring board, which includes: an insulating layer comprising a cured resin composition of any one of the technical solutions of the first to fifth technical solutions of the present invention; and wiring.

[0209] The seventh technical solution of the present invention relates to a semiconductor package, which includes: the wiring board according to the sixth technical solution of the present invention; and a semiconductor chip mounted on the wiring board.

[0210] According to the present invention, cured resin compositions with low dielectric properties such as low relative permittivity and low surface roughness after plasma treatment can be provided. Furthermore, according to the present invention, wiring boards and semiconductor packages obtained using cured resin compositions can be provided.

[0211] The present invention will be further described in detail below through embodiments; however, the scope of the present invention is not limited to these embodiments.

[0212] Example

[0213] [Examples 1-3 and Comparative Example 1]

[0214] The components used in preparing the resin composition in this embodiment will be described.

[0215] (Elastomer)

[0216] Elastomer-1: Styrene-butadiene-styrene copolymer (liquid 1,2-SBS manufactured by Nippon Soda Corporation)

[0217] Elastomer-2: Partially hydrogenated styrene (ethylene / butene) styrene copolymer (Tuftec P1500 manufactured by Asahi Kasei Corporation)

[0218] Elastomer-3: Hydrogenated styrene (ethylene / butene) styrene copolymer (Tuftec H1221 manufactured by Asahi Kasei Corporation)

[0219] (Curing compounds)

[0220] PPE: Modified polyphenylene ether compound (a modified polyphenylene ether in which the terminal hydroxyl groups have been modified with methacrylamide groups, SA9000 manufactured by SABIC Innovative Plastics, with a number average molecular weight of Mn2300).

[0221] (Curing agent)

[0222] TAIC: Triallyl isocyanurate (TAIC manufactured by Nippon Chemical Co., Ltd.)

[0223] (Reaction initiator)

[0224] PBP: α,α'-Di(tert-butylperoxide-m-isopropyl)benzene (PERBUTYL P (PBP) manufactured by Nippon Oil Co., Ltd.)

[0225] 2E4MZ: 2-Ethyl-4-methylimidazole (2E4MZ manufactured by Shikoku Chemical Industry Co., Ltd.)

[0226] (Other ingredients)

[0227] Epoxidized PB: Epoxidized polybutadiene (JP-100 manufactured by Nippon Soda Co., Ltd.)

[0228] Flame retardant: Phosphine oxide flame retardant (p-xylenebis(diphenylphosphine oxide), PQ60 manufactured by Jin Yi Chemical Co., Ltd.)

[0229] (Filling material)

[0230] Silica particles 1: D50: 180nm silica particles (K180SV-C1 manufactured by Admatechs Company Limited)

[0231] Silica particles 2: D50: 500nm silica particles (SC2300-SVJ manufactured by Yatuma Co., Ltd.)

[0232] Hollow silica particles 1: D50: 2000nm hollow silica particles (HS200 manufactured by AGC Si-Tech Co., Ltd., specific gravity 0.46)

[0233] Hollow silica particles 2: D50: 580nm silica particles (hollow silica manufactured by Yatoma Co., Ltd., specific gravity 1.4)

[0234] (Evaluation of substrate manufacturing)

[0235] First, a resin composition was prepared according to the composition (parts by mass) listed in Table 1. It should be noted that, relative to the resin composition, the content of the filler material was 28.5% by mass in Example 1, 12.7% by mass in Example 2, 29.5% by mass in Example 3, and 37.3% by mass in the comparative example. Using this resin composition, according to... Figure 1The method shown manufactures an evaluation substrate on which a conductor layer is formed on an insulating layer formed from a cured resin composition. Specifically, as the resin layer 12, a layer formed from the resin composition is heated from room temperature to 130°C and held at that temperature for 30 minutes, then heated to 220°C and held at that temperature for 2 hours to cure the resin layer 12, thereby obtaining the insulating layer 14. That is, the insulating layer 14 is a layer formed from the cured resin composition. In addition, as the plasma treatment, oxygen plasma treatment is performed. The sputtering treatment is as follows: a Ti layer of 50-100 nm is formed as the seed bonding layer, and a Cu layer of 150-250 nm is formed as the main body of the seed layer. Then, as the conductor layer, a Cu layer of 15-35 μm is formed by electrolytic plating.

[0236] [Dielectric properties (relative permittivity Dk and dielectric loss factor Df)]

[0237] The relative permittivity and dielectric loss factor of the insulating layer (the cured form of the resin composition) at 10 GHz were determined using the resonant cavity perturbation method. Specifically, the relative permittivity (Dk) and dielectric loss factor (Df) of the insulating layer at 10 GHz were determined using a network analyzer (N5230A manufactured by Keysight Technologies, Inc.).

[0238] [Energy Storage Modulus]

[0239] The insulating layer (the cured form of the resin composition) was cut into 10mm × 40mm pieces and mounted on a dynamic viscoelasticity measuring device (DMS6100 manufactured by Seiko Instruments Inc.). The storage modulus (MPa) at 40°C was measured using a strain amplitude of 10μm, a frequency of 10Hz (sine wave), and a heating rate of 5°C / min.

[0240] Coefficient of thermal expansion

[0241] The insulating layer (the cured product of the resin composition) was used as a test piece, and the coefficient of thermal expansion in the Y-axis direction (CTE: ppm / ℃) was determined according to JIS C 6481 by the TMA (Thermo-mechanical analysis) method. The measurement was performed using a TMA apparatus (TMA6000 manufactured by Seiko Electronics Nanotechnology Co., Ltd.) within the temperature range of 50–100℃.

[0242] [Surface roughness Ra before plasma treatment]

[0243] Surface roughness analysis was performed using a scanning confocal laser microscope (LEXT OLS3000 manufactured by Olympus Corporation), and the surface roughness Ra of the insulating layer (cured product of the resin composition) before plasma treatment was measured.

[0244] [Surface roughness Ra after plasma treatment]

[0245] Surface roughness analysis was performed using a scanning confocal laser microscope (LEXT OLS3000 manufactured by Olympus Corporation), and the surface roughness Ra of the insulating layer (cured product of the resin composition) after plasma treatment was measured.

[0246] These results, together with the composition of the resin composition, are shown in Table 1.

[0247] [Table 1]

[0248]

[0249] As shown in Table 1, for cured resin compositions containing filler material with a particle size D50 of less than 2100 nm in the cumulative particle size distribution based on volume, and whose content is less than 35% by mass, the cases where the relative permittivity of the cured resin composition is less than 2.6 at 10 GHz and the surface roughness Ra of the cured resin composition is less than 100 nm (0.1 μm) (Examples 1-3) are compared with the cases where the above conditions are not met (Comparative Examples). The cured resin compositions have lower dielectric properties such as relative permittivity and lower surface roughness after plasma treatment.

[0250] This application is based on Japanese Patent Application No. 2023-201907, filed on November 29, 2023, the contents of which are included in this application.

[0251] To illustrate the invention, the present invention has been appropriately and sufficiently described above through embodiments. However, it should be recognized that those skilled in the art can readily make changes and / or modifications to the above embodiments. Therefore, any changes or modifications implemented by those skilled in the art that do not depart from the scope of protection of the claims set forth in the claims can be interpreted as being included within the scope of protection of the claims.

[0252] Industrial availability

[0253] According to the present invention, cured resin compositions with low dielectric properties such as low relative permittivity and low surface roughness after plasma treatment can be provided. Furthermore, according to the present invention, wiring boards and semiconductor packages obtained using cured resin compositions can be provided.

Claims

1. A cured product of a resin composition, characterized in that, The resin composition contains a filler material. The cumulative particle size distribution of the filler material based on volume has 50% of the particle size D50 below 2100 nm. The content of the filler material relative to the resin composition is less than 35% by mass. The solidified material has a relative permittivity of less than 2.6 at 10 GHz. The surface roughness Ra of the cured material is less than 100 nm.

2. The cured product of the resin composition according to claim 1, characterized in that, The 50% particle size D50 in the cumulative particle size distribution of the volumetric reference of the filler material is 100–700 nm.

3. The cured product of the resin composition according to claim 1, characterized in that, The coefficient of thermal expansion is less than 80 ppm / ℃.

4. The cured product of the resin composition according to claim 1, characterized in that, The resin composition also contains an elastomer. The elastomer content is greater than 10% by mass relative to the resin composition.

5. The cured product of the resin composition according to claim 1, characterized in that, The filler material comprises at least one selected from the group consisting of polystyrene particles, hollow polystyrene particles, inorganic particles, and hollow inorganic particles.

6. A wiring board, characterized in that... include: An insulating layer comprising the cured resin composition of any one of claims 1 to 5; as well as wiring.

7. A semiconductor package, characterized in that... include: The wiring board according to claim 6; as well as Semiconductor chips mounted on the wiring board.

Images