Resin composition, sheet-shaped material, printed wiring board, and semiconductor device

Abstract

This resin composition contains an epoxy-modified double bond–containing hydrocarbon polymer, a thermoplastic elastomer, and an inorganic filler.

Description

Resin compositions, sheet materials, printed circuit boards, and semiconductor devices

[0001] This disclosure relates to resin compositions, sheet materials, printed circuit boards, and semiconductor devices.

[0002] In recent years, electronic devices have become smaller and more high-performance, and in multilayer printed circuit boards, the build-up layers have become more complex, leading to finer and denser wiring. Along with this finer and denser wiring, various performance characteristics are required of the insulating layers in multilayer printed circuit boards.

[0003] For example, build-up layers require a low coefficient of linear thermal expansion to reduce warpage after semiconductor packaging. One method for achieving a low coefficient of linear thermal expansion is to fill thermosetting resins with a high concentration of inorganic fillers.

[0004] On the other hand, in order to further improve the performance and functionality of semiconductor devices, it is becoming increasingly important to mount multiple individually manufactured semiconductor chips on a multilayer printed circuit board to enhance the overall functionality. For example, in order to consolidate more semiconductor chips, attempts have been made to use glass as the core material of the printed circuit board, which has high dimensional accuracy and a coefficient of linear thermal expansion similar to that of silicon, which constitutes the semiconductor chips, from the viewpoint of making the multilayer printed circuit board larger (see, for example, Patent Document 1). When multiple insulating layers are provided on a glass core, it is also necessary to lower the coefficient of linear thermal expansion of the insulating layer so as to approach that of the glass.

[0005] Furthermore, in recent years, computers and information and communication equipment have become increasingly high-performance and sophisticated, and in order to process large amounts of data at high speed, the signals they handle tend to be at higher frequencies. To suppress transmission losses due to high frequencies, materials with low dielectric constants in the high-frequency range are desired.

[0006] Under these circumstances, the objective is to provide a resin composition that yields an insulating layer with excellent dielectric loss tangent and thermal expansion coefficient, as well as excellent fracture elongation, surface roughness, and peel strength. To address this, a resin composition has been proposed that comprises an epoxy resin, an active ester compound, a carbodiimide compound, a thermoplastic resin, and an inorganic filler, wherein the inorganic filler content is 40% by mass or more relative to the non-volatile components in the resin composition (see, for example, Patent Document 2).

[0007] Japanese Patent No. 7439497, Japanese Unexamined Patent Publication No. 2016-27097

[0008] In the resin composition containing the active ester curing agent disclosed in Patent Document 2, the reduction in the coefficient of linear thermal expansion is insufficient, so an inorganic filler is densely packed. However, dense packing of inorganic filler increases the elastic modulus of the cured product, making the build-up layer prone to peeling. In particular, when the resin composition described in Patent Document 2 is used as a build-up layer on a glass core, cracking of the glass core and peeling of the build-up layer are more likely to occur.

[0009] This disclosure has been made in view of the above circumstances, and aims to provide a resin composition, a sheet-like material, a printed circuit board, and a semiconductor device that can lower the dielectric constant, elastic modulus, and linear thermal expansion coefficient when cured.

[0010] This disclosure includes the following embodiments: <1> A resin composition comprising an epoxy-modified double-bond-containing hydrocarbon polymer, a thermoplastic elastomer, and an inorganic filler. <2> The resin composition according to <1>, further comprising a curing agent. <3> The resin composition according to <2>, wherein the curing agent comprises at least one selected from the group consisting of acid anhydrides and active ester compounds. <4> The resin composition according to <3>, wherein the acid anhydride comprises at least one selected from the group consisting of acid anhydrides that are liquid at 25°C, acid anhydride-modified polybutadiene, and acid anhydride-modified styrene-ethylene-butylene-styrene block copolymer (SEBS). <5> The resin composition according to any one of <1> to <4>, wherein the thermoplastic elastomer comprises a thermoplastic elastomer having structural units derived from styrene. <6> The resin composition according to any one of <1> to <5>, wherein the thermoplastic elastomer comprises a hydrogenated styrene-based thermoplastic elastomer. <7> The resin composition according to any one of <1> to <6>, wherein the epoxy-modified double-bond-containing hydrocarbon polymer comprises at least one selected from the group consisting of epoxy-modified polybutadiene and epoxy-modified polyisoprene. <8> The resin composition according to any one of <1> to <7>, further comprising a maleimide compound. <9> The resin composition according to <8>, wherein the maleimide compound comprises at least one selected from the group consisting of a maleimide resin having one or more N-substituted maleimide groups, a maleimide resin containing a condensed ring, and an aliphatic bismaleimide compound. <10> The resin composition according to any one of <1> to <9>, wherein the inorganic filler comprises silica particles. <11> The resin composition according to any one of <1> to <10>, wherein the inorganic filler comprises silica particles with an average particle size of 0.01 μm to 20 μm. <12> A sheet-like material comprising the resin composition according to any one of <1> to <11>. <13> A printed circuit board having a cured product of the resin composition described in any one of <1> to <11>. <14> A semiconductor device having the printed circuit board described in <13>.

[0011] According to this disclosure, it is possible to provide a resin composition, a sheet-like material, a printed circuit board, and a semiconductor device that can lower the dielectric constant, elastic modulus, and linear thermal expansion coefficient when cured.

[0012] This figure illustrates an example of a method for manufacturing a printed circuit board according to the present disclosure.

[0013] The following describes in detail the forms for implementing this disclosure. However, this disclosure is not limited to the following embodiments. In the following embodiments, the components (including elemental steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and they do not limit this disclosure. In numerical ranges indicated using "~" in this disclosure, the numerical values ​​before and after "~" are included as the minimum and maximum values, respectively. In numerical ranges described in stages in this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Also, in numerical ranges described in this disclosure, the upper or lower limit of that numerical range may be replaced with the value shown in the example. In this disclosure, each component may contain multiple types of the corresponding substance. If multiple types of the substance corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple types of substances present in the composition unless otherwise specified. In this disclosure, each component may contain multiple types of particles. If multiple types of particles corresponding to each component are present in the composition, the particle size of each component refers to the value for a mixture of such multiple types of particles present in the composition, unless otherwise specified. In this disclosure, the term "layer" includes cases where the layer is formed over the entire region when the region in which the layer exists is observed, as well as cases where it is formed only on a part of the region. In this disclosure, the term "stacked" refers to stacking layers, and two or more layers may be bonded together or detachable.

[0014] In this disclosure, "resin composition" means a mixture of two or more components containing at least a resin, and if the resin is a thermosetting resin, it also includes the mixture in the B-stage state. However, the types and amounts of each component in the B-stage resin composition mean the types and amounts of each component before reaching the B-stage state, that is, the types and amounts of components blended when manufacturing the resin composition.

[0015] In this disclosure, "(meth)acrylate" means "acrylate" and its corresponding "methacrylate." Similarly, "(meth)acrylic" means "acrylic" and its corresponding "methacrylic," and "(meth)acryloyl" means "acryloyl" and its corresponding "methacryloyl."

[0016] In this disclosure, "molecular weight" of a compound means the molecular weight that can be calculated from the structural formula of the compound if the compound is not a polymer and its structural formula can be identified, and if the compound is a polymer, it means the number-average molecular weight unless otherwise specified.

[0017] In this disclosure, the number-average molecular weight refers to the value measured in polystyrene equivalent by gel permeation chromatography (GPC). Specifically, the GPC measurement in this disclosure can be performed under the following conditions. Note that the apparatus is not limited to the one described below if similar conditions can be met. Column: "TSKgel SuperHZM-N", "TSKgel SuperHZM-M", and "TSKgel SuperH-RC" (Tosoh Corporation, packed columns for HPLC) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Column temperature: 40°C Detector: RI

[0018] In this disclosure, "liquid" means that the viscosity calculated by the following measurement method is 100,000 mPa·s or less. Apparatus: E-type viscometer Cone rotor: 1°34' × R24 Temperature: 25℃ Sample volume: 1.0 mL Rotation speed: 20 revolutions / min In this disclosure, viscosity at 25℃ means viscosity measured by the above method.

[0019] When embodiments are described in this disclosure with reference to the drawings, the configuration of such embodiments is not limited to the configuration shown in the drawings. Furthermore, the sizes of the components in each figure are conceptual, and the relative relationships between the sizes of the components are not limited thereto.

[0020] The mechanisms of action described in this disclosure are speculative and do not limit the mechanisms by which the resin composition according to this embodiment exerts its effects. Embodiments also include any combination of the information described in this disclosure.

[0021] <Resin Composition> The resin composition of this disclosure contains an epoxy-modified double-bond-containing hydrocarbon polymer, a thermoplastic elastomer, and an inorganic filler. Hereinafter, the "epoxy-modified double-bond-containing hydrocarbon polymer" will also be referred to as the "specific epoxy-modified polymer." The above configuration of the resin composition makes it possible to lower the dielectric constant, elastic modulus, and linear thermal expansion coefficient when it is cured. The reason for this is not clear, but it is presumed to be as follows.

[0022] Since specific epoxy-modified polymers are hydrocarbon polymers, they have a high proportion of hydrocarbons and a low content of polar groups. This allows for a lower dielectric constant when cured. Furthermore, because the double-bond-containing hydrocarbon polymer is epoxy-modified, the curing reaction by the epoxy groups keeps the linear thermal expansion coefficient of the cured product low. In addition, the double bonds in polyolefins polymerize and cure to form a three-dimensional cross-linked structure, further reducing the linear thermal expansion coefficient. As a result of the above, it is possible to lower the linear thermal expansion coefficient, eliminating the need for excessively high inorganic filler content, and consequently, lowering the elastic modulus.

[0023] Furthermore, it is believed that the hydrocarbon moieties in the specific epoxy-modified polymer and the thermoplastic elastomer relax the stress in the cured product and lower its elastic modulus. Moreover, if the thermoplastic elastomer contains structural units derived from styrene, in addition to the stress relaxation effect, the proportion of hydrocarbons can be increased and the content of polar groups can be reduced. Therefore, the dielectric constant can be further reduced in the cured product. In addition, if the thermoplastic elastomer contains structural units derived from styrene, it is also possible to achieve high resistance to the roughening treatment performed when forming copper wiring.

[0024] Furthermore, if the curing agent is selected from the group consisting of acid anhydrides and active ester compounds, a polar hydroxyl group is not generated when it reacts with the epoxy group, making it possible to lower the dielectric loss tangent of the cured product.

[0025] The following describes each component that may be contained in the resin composition of this disclosure.

[0026] (Specific Epoxy Modified Polymer) The specific epoxy modified polymer is not particularly limited as long as it is a compound obtained by introducing one or more epoxy groups into a double-bond-containing hydrocarbon polymer. The specific epoxy modified polymer may be used alone or in combination of two or more types. The specific epoxy modified polymer preferably has a structural unit derived from an olefin containing two or more double bonds. At least one of the two or more double bonds undergoes a polymerization reaction to become the main chain of the hydrocarbon polymer, and at least one remains in the hydrocarbon polymer. The number of double bonds included in the above structural unit may be one or more, and is preferably one from the viewpoint of availability (or elastic modulus). The number of carbon atoms in the olefin included in the above structural unit is preferably 4 to 6, more preferably 4 to 5, and even more preferably 4.

[0027] Examples of the specific epoxy-modified polymer include epoxy-modified polybutadiene, epoxy-modified polyisoprene, epoxy-modified polycyclopentadiene, epoxy-modified polycyclohexadiene, etc. It preferably contains at least one selected from the group consisting of epoxy-modified polybutadiene and epoxy-modified polyisoprene, and more preferably contains epoxy-modified polybutadiene. Epoxy-modified polybutadiene is liquid at room temperature (25°C), is easy to flow when laminated on a printed wiring board, and can reduce the stress during embedding into the printed wiring board. From the viewpoints of electrical properties and stress relaxation, it is more preferably epoxidized polybutadiene in which an epoxy group is introduced by oxidation of the vinyl group of 1,2-polybutadiene.

[0028] The amount of the introduced epoxy group is not particularly limited. From the viewpoint of the thermal stability of the cured product, the epoxy equivalent of the specific epoxy-modified polymer is preferably 150 g / eq to 300 g / eq, more preferably 180 g / eq to 280 g / eq, and still more preferably 200 g / eq to 250 g / eq.

[0029] Also, the molecular weight of the specific epoxy-modified polymer is not particularly limited, but from the viewpoints of embedability and thermal stability, the number average molecular weight is preferably 1000 to 10000, and particularly preferably 1100 to 5000.

[0030] The specific epoxy-modified polymer is preferably a compound represented by the following formula (1).

[0031]

[0032] In formula (1), m represents an integer of 1 to 30, preferably 2 to 30, more preferably 2 to 20, and still more preferably 3 to 15. In formula (1), n represents an integer of 1 to 100, preferably 2 to 80, more preferably 3 to 50, and still more preferably 5 to 40.

[0033] In the compound represented by formula (1), the structural unit having an epoxy-modified site (the part enclosed by m) and the structural unit of an olefin containing a double bond (the part enclosed by n) may be randomly arranged, block-arranged, or alternately arranged.

[0034] The specific epoxy-modified polymer may be synthesized or a commercially available product may be used. Examples of commercially available epoxy-modified polybutadienes include NISSO-PB JP series manufactured by Nippon Soda Co., Ltd., RICON series manufactured by Cray Valley Co., and the like.

[0035] The content of the specific epoxy-modified polymer is not particularly limited, but from the viewpoints of the dielectric constant of the cured product and the fluidity during embedding, it is preferably 0.1% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, and even more preferably 1% by mass to 8% by mass with respect to the total amount (100% by mass) excluding the solvent in the resin composition.

[0036] (Thermoplastic elastomer) As the thermoplastic elastomer, general thermoplastic elastomers may be applied, and it may be used alone or in combination of two or more. From the viewpoints of further reducing the dielectric constant when formed into a cured product and exhibiting high resistance to the roughening treatment performed when forming copper wiring, it preferably contains a thermoplastic elastomer having a structural unit derived from styrene. From the viewpoint of keeping the dielectric constant and dielectric tangent low, it is more preferable to contain a hydrogenated styrene-based thermoplastic elastomer. Further, the thermoplastic elastomer more preferably contains a styrene-ethylene / butylene-styrene block copolymer (SEBS) which may be hydrogenated.

[0037] For SEBS that may be hydrogenated, a high melt flow rate (MFR) is preferable from the viewpoint of improving embedding properties. Under measurement conditions of 230°C and a load of 2.16 kgf (21.2 N), the MFR of SEBS that may be hydrogenated is preferably 0.1 g / 10 min to 30 g / 10 min, more preferably 1 g / 10 min to 25 g / 10 min, and even more preferably 10 g / 10 min to 20 g / 10 min. The styrene / ethylene-butylene ratio in SEBS that may be hydrogenated is not particularly limited, but from the viewpoint of fluidity, a mass ratio of 10 / 90 to 70 / 30 is preferred, and 19 / 81 to 31 / 69 is particularly preferred.

[0038] Examples of commercially available SEBS products that may be hydrogenated include the ToughTec H series, M series, and P series from Asahi Kasei Corporation, the Septon series from Kuraray Co., Ltd., and the Kraton G polymer series from Kraton Polymer Japan Co., Ltd.

[0039] The content of thermoplastic elastomer is not particularly limited, but is preferably 3% to 30% by mass, more preferably 4% to 25% by mass, and even more preferably 5% to 20% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent. When the content of thermoplastic elastomer is above the lower limit, the handling properties of the film tend to be better. Also, when the content of thermoplastic elastomer is below the upper limit, the embedding properties tend to be better.

[0040] (Inorganic Fillers) The resin compositions of this disclosure tend to exhibit better low thermal expansion, heat resistance, and flame retardancy when they contain inorganic fillers. One type of inorganic filler may be used alone, or two or more types may be used in combination.

[0041] Examples of inorganic filler materials include silica, alumina, titanium oxide, mica, beryllium, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay, talc, aluminum borate, and silicon carbide. Among these, silica, alumina, mica, and talc are preferred from the viewpoint of low thermal expansion, heat resistance, and flame retardancy, and it is more preferable to include at least one selected from the group consisting of silica and alumina, and even more preferable to include silica.

[0042] Examples of silica include precipitated silica, which is produced by the wet process and has a high water content, and dry-processed silica, which is produced by the dry process and contains almost no bound water. Dry-processed silica can be further categorized into crushed silica, fumed silica, and fused silica, depending on the manufacturing method.

[0043] The average particle size of the inorganic filler is not particularly limited, but from the viewpoint of dispersibility and fine wiring properties of the inorganic filler, it is preferably 0.01 μm to 20 μm, more preferably 0.1 μm to 10 μm, even more preferably 0.2 μm to 2 μm, and particularly preferably 0.3 μm to 1 μm. In this disclosure, the average particle size of the inorganic filler refers to the particle size at the point where the cumulative volume corresponds to 50% when the cumulative frequency distribution curve by particle size is calculated with the total volume of particles set to 100%. The average particle size of the inorganic filler can be measured, for example, with a particle size distribution analyzer using laser diffraction scattering.

[0044] The inorganic filler can take the form of a sphere, a crushed object, or the like, with a sphere being preferred.

[0045] The resin compositions of this disclosure may contain coupling agents for the purpose of improving the dispersibility of inorganic fillers and adhesion to organic components. Examples of coupling agents include silane coupling agents and titanate coupling agents. Among these, silane coupling agents are preferred. Examples of silane coupling agents include aminosilane coupling agents, vinylsilane coupling agents, and epoxysilane coupling agents.

[0046] When using a coupling agent, the surface treatment method for the inorganic filler may be an integral blend treatment method in which the coupling agent is added after the inorganic filler has been blended into the resin composition, or it may be a method in which the inorganic filler is pre-treated with the coupling agent by dry or wet surface treatment. Among these, from the viewpoint of more effectively expressing the characteristics of the inorganic filler, the method of pre-treating the inorganic filler with the coupling agent by dry or wet surface treatment is preferred. The inorganic filler may be pre-dispersed in an organic solvent to form a slurry before being mixed with other components in order to improve its dispersibility in the resin composition.

[0047] The inorganic filler content is not particularly limited, but is preferably 20% to 95% by mass, more preferably 40% to 90% by mass, and even more preferably 50% to 80% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent. When the inorganic filler content is above the lower limit, the low thermal expansion, heat resistance, and flame retardancy tend to be better. Also, when the inorganic filler content is below the upper limit, the moldability and conductive adhesion tend to be better.

[0048] (Curing Agent) The resin composition of this disclosure may further contain a curing agent. The curing agent can be any agent that reacts with the epoxy resin, and examples include amine-based curing agents, phenol-based curing agents, acid anhydride-based curing agents, and active ester compounds. The curing agent may be in liquid or solid form. The curing agent may be used alone or in combination of two or more types.

[0049] The curing agent preferably contains at least one selected from the group consisting of acid anhydrides and active ester compounds. These curing agents do not generate polar hydroxyl groups when they react with epoxy groups, and can reduce the dielectric loss tangent of the cured product.

[0050] From the viewpoint of low dielectric constant, low dielectric loss, and reduction of linear thermal expansion coefficient, the curing agent preferably contains an acid anhydride. The acid anhydride may be used alone or in combination of two or more types. The acid anhydride is not particularly limited as long as it contains an acid anhydride structure, but from the viewpoint of electrical properties and compatibility, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, nadic anhydride, and derivatives thereof can be used.

[0051] Furthermore, from the viewpoint of fluidity during embedding, it is preferable that the acid anhydride includes at least one selected from the group consisting of acid anhydrides that are liquid at 25°C, acid anhydride-modified polybutadiene, and acid anhydride-modified styrene-ethylene-butylene-styrene block copolymer (SEBS).

[0052] The acid anhydride that is liquid at 25°C is not particularly limited, but from the viewpoint of dielectric loss tangent, 3 or 4-methyl-1,2,3,6-tetrahydrophthalic anhydride (e.g., HN-2200 manufactured by Resonaq Corporation) and methyl-3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride (e.g., MHAC-P manufactured by Resonaq Corporation) are preferred.

[0053] Acid anhydride-modified SEBS is a thermoplastic elastomer having structural units derived from styrene, and can also contribute as the thermoplastic elastomer described above. However, if the resin composition contains acid anhydride-modified SEBS, the content of acid anhydride-modified SEBS is calculated as the content of the curing agent. Acid anhydride-modified SEBS may be hydrogenated.

[0054] The amount of acid anhydride introduced into acid anhydride-modified polybutadiene and acid anhydride-modified SEBS is not particularly limited. From the viewpoint of forming a crosslinked structure through a crosslinking reaction with epoxy groups, the acid values ​​of acid anhydride-modified polybutadiene and acid anhydride-modified SEBS are independently set at 1 mg CH₃. ３ONa / g~100mgCH ３ Preferably, it is ONa / g, 2mgCH ３ ONa / g~50mgCH ３ It is more preferable that the concentration be ONa / g, and 5 mg CH ３ ONa / g~20mgCH ３ It is even more preferable that the concentration is ONa / g.

[0055] Examples of acid anhydride-modified polybutadiene include maleic acid-modified polybutadiene. Acid anhydride-modified polybutadiene may be obtained by synthesis or commercially available products may be used. Examples of commercially available maleic acid-modified polybutadiene include the RICON MA series from Clay Valley. Examples of acid anhydride-modified SEBS include maleic acid-modified SEBS. Acid anhydride-modified SEBS may be obtained by synthesis or commercially available products may be used. Examples of commercially available maleic acid-modified SEBS include the ToughTec M series from Asahi Kasei Corporation and Kraton FG polymer from Kraton Corporation. The content of the curing agent is preferably 0.5% to 20% by mass, more preferably 1% to 15% by mass, and even more preferably 2% to 10% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent.

[0056] (Maleimide Compound) The resin composition of this disclosure may further contain a maleimide compound. The maleimide compound is not particularly limited as long as it is a maleimide compound having one or more N-substituted maleimide groups, and from the viewpoint of heat resistance, the maleimide compound is preferably a maleimide compound having two or more N-substituted maleimide groups. The maleimide compound may be used alone or two or more may be used in combination. From the viewpoint of solubility and low dielectric constant, the maleimide compound preferably contains at least one selected from the group consisting of a maleimide resin having one or more N-substituted maleimide groups, a maleimide resin containing a condensed ring, and an aliphatic bismaleimide compound.

[0057] Maleimide resins containing a condensed ring are preferably those having a condensed bicyclic structure and more preferably an indane ring from the viewpoints of dielectric properties, conductor adhesion, and ease of production. As the maleimide resin containing an indane ring, an aromatic bisimide resin containing an indane ring is preferred. In the present disclosure, the indane ring means a condensed bicyclic structure of an aromatic 6-membered ring and a saturated aliphatic 5-membered ring. At least one of the ring-forming carbon atoms forming the indane ring has a bonding group for bonding to other groups constituting the maleimide resin. The ring-forming carbon atom having the bonding group and the other ring-forming carbon atoms may not have a bonding group, a substituent, etc. other than the above bonding group, but preferably form a divalent group by having a bonding group other than the above.

[0058] In the maleimide resin containing an indane ring, the indane ring is preferably contained as a divalent group represented by the following formula (A1-1).

[0059] (In the formula, R ａ１ is an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a mercapto group. n ａ１ is an integer of 0 to 3. R ａ２ to R ａ４ are each independently an alkyl group having 1 to 10 carbon atoms. * represents a bonding site.)

[0060] The alkyl group having 1 to 10 carbon atoms represented by R ａ１ in the formula (A1-1) includes a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and the like. These alkyl groups may be either linear or branched. The alkyl group contained in the alkyloxy group having 1 to 10 carbon atoms and the alkylthio group having 1 to 10 carbon atoms represented by R ａ１ is the same as the alkyl group having 1 to 10 carbon atoms. The R ａ１Examples of aryl groups having 6 to 10 carbon atoms represented by R include the phenyl group and the naphthyl group. ａ１ The aryl groups included in the aryloxy group and arylthio group having 6 to 10 carbon atoms, as represented by , are the same as the aryl groups having 6 to 10 carbon atoms. ａ１ Examples of cycloalkyl groups having 3 to 10 carbon atoms represented by R include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, and cyclodecyl group. Among these, R ａ１ From the viewpoint of solvent solubility and reactivity, alkyl groups having 1 to 4 carbon atoms, cycloalkyl groups having 3 to 6 carbon atoms, or aryl groups having 6 to 10 carbon atoms are preferred, with alkyl groups having 1 to 4 carbon atoms being more preferred.

[0061] R ａ２ ~R ａ４ Examples of C1-C10 alkyl groups represented by include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl groups. These alkyl groups may be linear or branched. Among these, R ａ２ ~R ａ４ The alkyl group is preferably a C1-C4 alkyl group, more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0062] n in equation (A1-1) ａ１ n is an integer between 0 and 3. ａ１ If there are 2 or 3, then multiple R ａ１ They may be the same or they may be different.

[0063] Examples of aromatic bismaleimide resins containing an indan ring include the following:

[0064]

[0065] n in each equation ａ３ is an integer greater than or equal to 1.

[0066] The number-average molecular weight of the maleimide resin containing the condensed ring is not particularly limited, but is preferably 600 to 3,000, more preferably 800 to 2,000, and even more preferably 1,000 to 1,500, from the viewpoint of compatibility with other resins, conductive adhesion, and heat resistance.

[0067] The aliphatic bismaleimide compound may be the compound shown in the following formula (A2-1).

[0068] X in equation (A2-1) ａ１１ This is a divalent organic group that does not contain a fused ring of an aromatic ring and an aliphatic ring, and examples include a phenylene group which may have substituents, and an alkylene group which may have substituents. In particular, from the viewpoint of compatibility with other components, X ａ１１ Preferably, the alkylene group has a substituent. Examples of such materials include 1,6-bismaleimide-(2,2,4-trimethyl)hexane (for example, BMI-TMH manufactured by Yamato Chemical Industries, Ltd.).

[0069] The maleimide compound content is not particularly limited, but from the viewpoint of fluidity during embedding and heat resistance, it is preferably 0.1% to 20% by mass, more preferably 0.5% to 10% by mass, and even more preferably 1% to 5% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent.

[0070] (Other Components) The resin composition of this disclosure may contain other components. Examples of other components include reactive liquid compounds, curing accelerators, polymerization initiators, organic solvents, and other additives. Each of these may be used individually or in combination of two or more.

[0071] -Reactive Liquid Compounds- Reactive liquid compounds are compounds that are liquid at 25°C and have a curing-reactive site (hereinafter also referred to as a reactive group). When a resin composition contains a reactive liquid compound, its fluidity during embedding is increased, and the heat resistance of the cured product can be improved by forming a cross-linked structure through curing. Reactive liquid compounds may be used alone or in combination of two or more types.

[0072] The reactive liquid compound preferably has one or more reactive groups selected from vinyl groups, allyl groups, maleimide groups, (meth)acryloyl groups, epoxy groups, hydroxyl groups, carboxyl groups, amino groups, and other carbon-carbon double bonds. Among these, (meth)acryloyl groups, epoxy groups, and other carbon-carbon double bonds are more preferred as reactive groups, and (meth)acryloyl groups and other carbon-carbon double bonds are even more preferred from the viewpoint of easily obtaining better dielectric properties. Specific examples of reactive liquid compounds having a (meth)acryloyl group as a reactive group include (meth)acrylic acid esters such as mono(meth)acrylic acid esters, di(meth)acrylic acid esters, and trifunctional or more (meth)acrylic acid esters.

[0073] Examples of mono(meth)acrylic acid esters include methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, pentyl(meth)acrylate, hexyl(meth)acrylate, heptyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, octyl(meth)acrylate, isooctyl(meth)acrylate, nonyl(meth)acrylate, decyl(meth)acrylate, dodecyl(meth)acrylate, lauryl(meth)acrylate, tridecyl(meth)acrylate, and stearyl(meth)acrylate. Examples include 2-hydroxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclopentyl (meth)acrylate, benzyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.

[0074] Examples of di(meth)acrylic acid esters include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, tricyclodecane di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, and triethylene glycol di(meth)acrylate. Examples include polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol F di(meth)acrylate, and dioxane glycol di(meth)acrylate. Examples of dioxane glycol di(meth)acrylate include 2-[5-ethyl-5-[(acryloyloxy)methyl]-1,3-dioxan-2-yl]-2,2-dimethylethyl acrylate.

[0075] Examples of (meth)acrylic acid esters with three or more functions include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0076] Among the above, di(meth)acrylic acid esters are preferred as (meth)acrylic acid esters from the viewpoint of low elastic modulus and low dielectric constant. As di(meth)acrylic acid esters, diacrylic acid esters represented by the following formula (B-1) and dimethacrylic acid esters represented by the following formula (B-2) are preferred, and dimethacrylic acid esters represented by the following formula (B-2) are more preferred from the viewpoint of low dielectric constant.

[0077] (In the formula, R ｂ１ (This refers to an alkylene group having 1 to 20 carbon atoms.)

[0078] R in equations (B-1) and (B-2)ｂ１ The number of carbon atoms in the alkylene group having 1 to 20 carbon atoms represented by is preferably 4 to 18, more preferably 6 to 15, and even more preferably 8 to 12. Examples of alkylene groups having 1 to 20 carbon atoms include methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, tetradecylene, and pentadecylene. The alkylene group may be linear, branched, or cyclic, but linear is preferred from the viewpoint of availability.

[0079] Other specific examples of reactive liquid compounds having carbon-carbon double bonds include polybutadiene, polyisoprene, styrene-butadiene-styrene polymer (SBS), oleic acid esters, linoleic acid esters, linolenic acid esters, castor oil derivatives, and the like. Polybutadiene, styrene-butadiene-styrene polymer, and oleic acid esters are particularly preferred because they can effectively reduce the elastic modulus of the cured product.

[0080] When the resin composition contains a reactive liquid compound, the content of the reactive liquid compound is not particularly limited, but is preferably 0.1% to 30% by mass, more preferably 0.5% to 25% by mass, and even more preferably 1% to 20% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent. When the content of the reactive liquid compound is above the lower limit, it tends to be easier to obtain better flexibility. Also, when the content of the reactive liquid compound is below the upper limit, it tends to be easier to suppress the generation of volatile components during heat curing.

[0081] (Curing accelerator) The resin composition of this disclosure may further contain a curing accelerator. The curing accelerator promotes the reaction between specific epoxy-modified polymers, or the reaction between specific epoxy-modified polymers and the curing agent, making it possible to carry out the crosslinking reaction even under mild conditions of about 120°C to 200°C.

[0082] Examples of curing accelerators include amine-based curing accelerators, guanidine-based curing accelerators, imidazole-based curing accelerators, phosphonium-based curing accelerators, and metal-based curing accelerators. Curing accelerators may be used individually or in combination of two or more. Among these, imidazole-based curing accelerators are preferred from the viewpoint of the curability of the resin composition and the physical properties of the cured product. Examples of amine-based curing accelerators include trialkylamines such as triethylamine and tributylamine; 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo[5,4,0]-undecene. Examples of imidazole-based curing accelerators include imidazole and imidazole derivatives such as 2-ethyl-4-methylimidazole and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole.

[0083] If the resin composition of this disclosure contains a curing accelerator, the content of the curing accelerator is not particularly limited, but from the viewpoint of the curability of the resin composition and the physical properties of the cured product, it is preferably 0.005% to 3% by mass, and more preferably 0.01% to 1% by mass, based on the total amount of the resin composition excluding the solvent (100% by mass).

[0084] (Polymerization Initiator) The resin composition of this disclosure may further contain a polymerization initiator. Radicals generated by the reaction of the polymerization initiator promote the polymerization reaction of the carbon-carbon double bond in the specific epoxy-modified polymer, forming a crosslinked structure and thereby increasing heat resistance. Examples of polymerization initiators include dialkyl peroxide-based organic peroxides. A single polymerization initiator may be used, or two or more may be used in combination. When the resin composition contains a polymerization initiator, the content of the polymerization initiator is not particularly limited, but is preferably 0.005% to 2% by mass, and more preferably 0.01% to 1% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent.

[0085] (Other Thermoplastic Resins) The resin composition of this disclosure may further contain other thermoplastic resins. Examples of other thermoplastic resins include polyvinyl acetal resins, polyimide resins, polyamide-imide resins, polyethersulfone resins, cycloolefin polymers, and polysulfone resins. The other thermoplastic resins may be used individually or in combination of two or more. When the resin composition of this disclosure contains other thermoplastic resins, the content of the other thermoplastic resins is not particularly limited, but is preferably 0.01% to 5% by mass, and more preferably 0.5% to 3% by mass, based on the total amount (100% by mass) of the resin composition excluding the solvent. The resin composition of this disclosure may not contain other thermoplastic resins, depending on the desired performance.

[0086] (Other Thermosetting Resins) The resin composition of this disclosure may further contain other thermosetting resins. Examples of other thermosetting resins include vinyl benzyl resin, acrylic resin, maleimide resin, blocked isocyanate resin, epoxy resin, etc. The resin composition may be used alone or in combination of two or more types. The content of other thermosetting resins in the resin composition of this disclosure is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 2% by mass or less, and may contain no other thermosetting resins (0% by mass) depending on the desired performance.

[0087] (Organic Fillers) The resin compositions of this disclosure may further contain organic fillers. Examples of organic fillers include silicone powder, nylon powder, fluorine powder, and rubber particles. One type of organic filler may be used alone, or two or more types may be used in combination. When the resin composition of this disclosure contains organic fillers, the content of the organic fillers is not particularly limited, but is preferably 0.01% to 10% by mass, and more preferably 0.1% to 5% by mass, based on the total amount of the resin composition excluding the solvent (100% by mass). The resin compositions of this disclosure may not contain organic fillers, depending on the desired performance.

[0088] (Other Additives) The resin compositions of this disclosure may further contain other additives. Examples of other additives include flame retardants such as inorganic flame retardants and resin flame retardants; smear removers; thickeners such as olbene and bentone; adhesion promoters such as imidazole, thiazole, and triazole; colorants; and defoamers. Depending on the desired performance, the resin compositions of this disclosure may not contain the above-mentioned other additives.

[0089] (Organic Solvents) The resin composition of this disclosure may be a varnish-like resin composition containing an organic solvent (hereinafter also referred to as "resin varnish") from the viewpoint of ease of handling. Examples of organic solvents include ketone-based solvents such as acetone, methyl ethyl ketone (hereinafter also referred to as "MEK"), methyl isobutyl ketone, and cyclohexanone; acetic acid ester-based solvents such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitol-based solvents such as cellosolve and butyl carbitol; aromatic hydrocarbon-based solvents such as toluene and xylene; and amide-based solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. One organic solvent may be used alone, or two or more may be used in combination. Among these, ketone-based solvents are preferred from the viewpoint of solubility, and MEK and methyl isobutyl ketone are more preferred.

[0090] <Method for Manufacturing Resin Compositions> The resin composition of this disclosure can be manufactured by blending the above components and, if necessary, kneading and mixing them using kneading means such as a three-roll mill, ball mill, bead mill, or sand mill; or stirring means such as a high-speed rotary mixer, super mixer, or planetary mixer. The resin varnish can also be manufactured by dissolving or dispersing the above components in a solvent and, if necessary, mixing them using a homogenizer, high-speed rotary mixer, or the like, and performing a dispersion treatment.

[0091] <Physical Properties of Resin Composition> When the resin composition of this disclosure is a resin varnish, the viscosity at 25°C is preferably 5 mPas to 10,000 mPas, more preferably 10 mPas to 1,000 mPas, and even more preferably 20 mPas to 500 mPas. The viscosity of the resin composition at 25°C can be measured by the following method: Apparatus: E-type viscometer Cone rotor: 1°34' × R24 Temperature: 25°C Sample volume: 1.0 mL Rotation speed: 20 rpm

[0092] The dielectric constant (Dk) of the cured resin composition of this disclosure at 25°C and 10GHz may be less than 3.2, less than 3.0, or less than 2.9. A smaller dielectric constant (Dk) is preferable, and there is no particular limit to its lower limit, but considering the balance with other physical properties, it may be, for example, 2.4 or higher, or 2.5 or higher. The dielectric loss tangent (Df) of the cured resin composition of this disclosure at 25°C and 10GHz may be less than 0.01, 0.006 or lower, or 0.005 or lower. A smaller dielectric loss tangent (Df) is preferable, and there is no particular limit to its lower limit, but considering the balance with other physical properties, it may be, for example, 0.0010 or higher, or 0.0015 or higher. Here, the cured resin composition is obtained by preparing a resin film from the resin composition according to the method described in the examples, and heating the resin film according to the method described in the examples.

[0093] The storage modulus (E') of the cured resin composition of this disclosure is preferably 0.1 GPa to 10 GPa, more preferably 0.5 GPa to 5 GPa, and even more preferably 1 GPa to 4 GPa at 40°C. If the storage modulus is within the above range, peeling of the build-up layer is easily prevented, and even when glass is used as the core material, heat resistance is easily ensured while preventing cracking of the glass. The cured resin composition can be prepared as described above, and the storage modulus can be measured by the method described in the examples.

[0094] The linear thermal expansion coefficient (CTE1) of the cured resin composition of this disclosure in the range of 25°C to 150°C is preferably 5 ppm / °C to 100 ppm / °C, more preferably 7 ppm / °C to 50 ppm / °C, and even more preferably 10 ppm / °C to 30 ppm / °C. The linear thermal expansion coefficient (CTE2) of the cured resin composition of this disclosure in the range of 150°C to 240°C is preferably 5 ppm / °C to 70 ppm / °C, more preferably 10 ppm / °C to 50 ppm / °C, and even more preferably 15 ppm / °C to 40 ppm / °C. If the linear thermal expansion coefficient is within the above range, warping is easily suppressed, and even when glass is used as the core material, dimensional accuracy can be easily ensured while preventing glass breakage. The cured resin composition can be prepared as described above, and the linear expansion coefficient can be measured by the method described in the examples.

[0095] <Applications of the Resin Composition> The resin composition of this disclosure is suitable as a resin composition for forming an insulating layer in the manufacture of printed circuit boards (resin composition for the insulating layer of printed circuit boards), more suitable as a resin composition for forming a conductive layer by plating (resin composition for the insulating layer of printed circuit boards for forming a conductive layer by plating), and even more suitable as a resin composition for forming a build-up layer (resin composition for the build-up layer of printed circuit boards). The resin composition of this disclosure can also be applied to a circuit board in the form of a resin varnish to form an insulating layer, but industrially, it is preferable to use it in the form of a sheet material such as a resin film or prepreg. The softening point of the resin composition is preferably 40°C to 150°C from the viewpoint of lamination properties.

[0096] <Sheet-like Material> The sheet-like material of this disclosure includes the resin composition of this disclosure. The solvent content in the sheet-like material is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less. Examples of the sheet-like material of this disclosure include a resin film with a support having a resin composition layer formed by layering the resin composition of this disclosure on a support, a resin film peeled off from a support, and a prepreg obtained by impregnating a sheet-like reinforcing substrate with the resin composition of this disclosure.

[0097] A resin film with a support can be manufactured, for example, by applying a resin varnish onto the support using a die coater or the like, and then drying the organic solvent by methods such as heating or hot air blowing. Preferably, the drying conditions result in an organic solvent content of 10% by mass or less in the resin composition layer after drying, and more preferably 5% by mass or less. The specific conditions vary depending on the amount of organic solvent in the resin varnish, its boiling point, etc., but for example, a resin composition layer can be formed by drying a resin varnish containing 30% to 60% by mass of organic solvent at 50°C to 150°C for 30 seconds to 10 minutes.

[0098] The thickness of the resin composition layer is preferably 1 μm to 150 μm, more preferably 2 μm to 100 μm, even more preferably 3 μm to 70 μm, particularly preferably 5 μm to 50 μm, and most preferably 10 μm to 40 μm, from the viewpoint of achieving both insulation and thinning of the printed circuit board. The resin film with support may have multiple layers of resin composition. In addition, a protective film may be provided on the side of the resin composition layer opposite to the support, from the viewpoint of preventing the adhesion of dust and other debris to the surface of the resin composition layer and preventing scratches.

[0099] The support material is not particularly limited and includes organic resin films, metal foils, and release paper. Examples of organic resin films include polyolefins such as polyethylene and polyvinyl chloride; polyesters such as polyethylene terephthalate (hereinafter also referred to as "PET") and polyethylene naphthalate; and polycarbonate and polyimide. Among these, PET is preferred from the viewpoint of price and ease of handling. The metal foil is not particularly limited and includes copper foil and aluminum foil. When copper foil is used as the support material, the copper foil can be used as the conductive layer to form a circuit, and in this case, rolled copper, electrolytic copper foil, etc. can be used as the copper foil. The thickness of the copper foil is, for example, 2 μm to 36 μm. When using thin copper foil, a carrier-attached copper foil may be used from the viewpoint of improving workability. The support material may or may not be treated with matte treatment, corona treatment, release treatment, etc. The thickness of the support material is usually 10 μm to 150 μm, preferably 25 μm to 50 μm, and more preferably 25 μm to 45 μm. If the support is 10 μm or thicker, it becomes easier to handle. On the other hand, since the support is usually peeled off or removed in the end, it is preferable to have a thickness of 150 μm or less from the viewpoint of energy saving, etc.

[0100] Examples of protective films include films made of the same material as the support. The thickness of the protective film is, for example, 1 μm to 40 μm. The resin film with the support, on which the protective film is laminated, can also be stored by being wound into a roll.

[0101] The reinforcing base material in the prepreg is not particularly limited and may be a unidirectional material formed of fibrous reinforcing material, a woven (cloth) material, a braided material, or other fibrous base material. Specific examples of fibrous reinforcing materials constituting the fibrous base material include carbon fibers, glass fibers, alumina fibers, boron fibers, and aramid fibers. From the viewpoint of mechanical strength and weight reduction, carbon fibers are preferred. The reinforcing material may be used alone or in combination of two or more types.

[0102] The dielectric constant (Dk), dielectric loss tangent (Df), storage modulus (E'), and linear thermal expansion coefficient (CTE) of the cured sheet material of this disclosure at 25°C and 10 GHz can be found by referring to those described for the resin composition.

[0103] <Printed Wiring Board> The printed wiring board of this disclosure has a cured product of a resin composition. The printed wiring board of this disclosure may have a cured product obtained by coating the resin composition of this disclosure onto a circuit board and curing it, or it may have a cured product obtained by placing the sheet-like material of this disclosure onto a circuit board and curing it. From the viewpoint of workability, the latter is preferred for the printed wiring board. A method for manufacturing the printed wiring board of this disclosure using the sheet-like material of this disclosure will be described below with reference to Figure 1. Note that the method for manufacturing the printed wiring board is not limited to Figure 1.

[0104] When manufacturing a printed circuit board using the sheet material of this disclosure, first, as shown in Figure 1(B), the sheet material 10 of this disclosure is placed on one or both sides of a circuit board 20. Specifically, for example, after placing the sheet material 10 of this disclosure on the circuit board 20, it can be laminated onto the circuit board 20 by laminating it to the circuit board 20 while applying pressure and heating with a vacuum laminator. Examples of circuit boards 20 used in printed circuit boards include those with a patterned conductive layer (circuit) formed on one or both sides of a glass, glass epoxy, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, thermosetting polyphenylene ether substrate, etc. In Figure 1, as shown in Figure 1(A), a circuit board 20 with a conductive layer 22 formed thereon is used. From the viewpoint of adhesion, the surface of the conductive layer 22 of the circuit board 20 may be roughened in advance by blackening treatment or the like.

[0105] Next, as shown in Figure 1(C), the support 12 of the sheet-like material 10 is peeled off as needed, and then the sheet-like material 10 is heat-cured to form an insulating layer 14. The heating temperature during heat curing is not particularly limited, but is preferably 100°C to 300°C, more preferably 120°C to 280°C, and even more preferably 150°C to 250°C. The heating time during heat curing is not particularly limited, but is preferably 2 minutes to 300 minutes, more preferably 5 minutes to 200 minutes, and even more preferably 10 minutes to 150 minutes.

[0106] After forming the insulating layer 14 by the method described above, drilling may be performed as necessary, as shown in Figure 1(D). Drilling is a process of creating via holes, through holes, etc., in the circuit board 20 and the formed insulating layer 14 by methods such as drilling, laser, plasma, or a combination thereof. Lasers used for drilling include carbon dioxide lasers, YAG lasers, UV lasers, and excimer lasers.

[0107] Next, the surface of the insulating layer 14 may be roughened with an oxidizing agent. If via holes, through holes, etc. are formed in the insulating layer 14 and the circuit board 20, the so-called "smear" that occurs when these are formed may be removed with an oxidizing agent. The roughening treatment and smear removal may be performed together. The roughening treatment can form uneven anchors on the surface of the insulating layer 14. Examples of oxidizing agents include permanganates such as potassium permanganate and sodium permanganate; dichromate, ozone, hydrogen peroxide, sulfuric acid, and nitric acid. Among these, it is preferable to use aqueous sodium hydroxide solution of potassium permanganate and aqueous sodium hydroxide solution of sodium permanganate, which are commonly used as oxidizing agents in the manufacture of printed circuit boards by the build-up method.

[0108] The surface roughness of the insulating layer 14 after roughening treatment is preferably 300 nm or less, more preferably 200 nm or less, even more preferably 150 nm or less, particularly preferably 100 nm or less, and most preferably 60 nm or less, in terms of arithmetic mean roughness (Ra). When the arithmetic mean roughness (Ra) is within the above range, excellent fine wiring properties tend to be obtained. The lower limit of the arithmetic mean roughness (Ra) may be, for example, 10 nm or more, or 20 nm or more, from the viewpoint of adhesion with the conductor layer.

[0109] Next, as shown in Figure 1(E), a conductive layer 30 is formed on the surface of the roughened insulating layer 14. The conductive layer 30 can be formed, for example, by plating. Examples of plating methods include electroless plating and electrolytic plating. Examples of metals for plating include copper, gold, silver, nickel, platinum, molybdenum, ruthenium, aluminum, tungsten, iron, titanium, chromium, and alloys containing at least one of these metal elements. Among these, copper and nickel are preferred, and copper is more preferred. Alternatively, a method can be adopted in which a plating resist with a pattern in the reverse of the wiring pattern is formed first, and then the wiring pattern is formed by electroless plating only. Furthermore, annealing treatment may be performed after the conductive layer 30 is formed. By performing annealing treatment, the adhesive strength between the insulating layer 14 and the conductive layer 30 tends to be further improved and stabilized.

[0110] Known methods such as the subtractive method, the fully additive method, the semi-additive method (SAP: Semi-Additive Process), and the modified semi-additive method (m-SAP: modified Semi-Additive Process) can be used to pattern the conductive layer and form a circuit.

[0111] <Semiconductor Device> The semiconductor device of this disclosure has a printed circuit board of this disclosure. Examples of semiconductor devices include CPUs, GPUs, etc.

[0112] The embodiment will be described in detail below with reference to examples. However, this embodiment is not limited to the following examples.

[0113] [Examples 1-8, Comparative Examples 1-3] (Preparation of Resin Compositions) Each component listed in Table 1 was blended with toluene according to the blending amounts listed in Table 1, and then stirred and mixed at 25°C to prepare a resin composition with a solid content of approximately 50% by mass. In Table 1, the unit of the blending amount of each component is parts by mass, and in the case of a solution, it means parts by mass in terms of solid content. The blending amounts are shown to one decimal place, but the total may not equal 100 parts due to rounding. Details of each component are as follows.

[0114] (A1-1) Epoxy-modified double-bond-containing hydrocarbon polymer: Epoxy-modified polybutadiene with the following structure, in formula (1), m = 4 to 7, m + n = 16 to 25, number average molecular weight 1300, glass transition temperature -16°C, epoxy equivalent 205 g / eq) (A1-2) Epoxy-modified double-bond-containing hydrocarbon polymer: Epoxy-modified polybutadiene with the following structure, in formula (1), m = 8 to 11, m + n = 35 to 43, number average molecular weight 2200, glass transition temperature -7°C, epoxy equivalent 220 g / eq)

[0115] (A2): Epoxy resin A2-1: Cresol novolac type epoxy resin (epoxy equivalent 210 g / eq) A2-2: Bisphenol A type epoxy resin (epoxy equivalent 185 g / eq) A2-3: Biphenyl skeleton-containing epoxy resin (epoxy equivalent 288 g / eq)

[0116] (B) Thermoplastic elastomers B-1: Styrene-ethylene-butylene-styrene block copolymer (SEBS) (styrene content 30% by mass, MFR at 230°C and 2.16 kgf load: 25 g / 10 min) B-2: Hydrogenated styrene-based thermoplastic elastomer (SEBS, styrene / ethylene-butylene ratio (by mass): 20 / 80, MFR at 230°C and 2.16 kgf load: 13.0 g / 10 min) B-3: Maleic acid-modified styrene-based thermoplastic elastomer (SEBS, styrene / ethylene-butylene ratio (by mass): 30 / 70, MFR at 230°C and 2.16 kgf load: 5 g / 10 min, acid value: 10 mg CH3ONa / g)

[0117] (C) Inorganic filler C-1: Silica inorganic filler, average particle size 1 μm C-2: Silica inorganic filler, average particle size 0.5 μm

[0118] (D) Curing agent D-1: Methyl-3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride D-2: Maleic acid-modified polybutadiene (number average molecular weight 2900, acid value 74 mg KOH / g) D-3: Phenoxy resin (weight average molecular weight 30000, weight average molecular weight 30000) D-4: Activated ester resin (active ester group equivalent 223 g / eq) D-5: Novolac-type phenolic resin curing agent (hydroxyl group equivalent 125 g / eq)

[0119] (E) Maleimide compounds E-1: 1,6-bismaleimide-(2,2,4-trimethyl)hexane E-2: Bismaleimide compound containing an indane skeleton (corresponding to formula A1-3-1)

[0120] (F) Reactive liquid compounds F-1: Tricyclodecanedimethanol dimethacrylate F-2: Polybutadiene: Liquid polybutadiene (number average molecular weight 1200, 1,2-vinyl group content 85%) F-3: Liquid styrene-butadiene-styrene block polymer, styrene content 20%, number average molecular weight 4500, 1,2-vinyl group content 80% or more)

[0121] (G) Curing accelerators G-1: 4-dimethylaminopyridine G-2: 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole

[0122] (H) Polymerization initiator: α,α'-di(t-butylperoxy)diisopropylbenzene (I) Coupling agent I-1: 3-methacryloxypropyltrimethoxysilane I-2: vinyltrimethoxysilane

[0123] (Manufacturing of resin film) The resin composition obtained in each example was applied to the release surface of a 25 μm thick PET film (manufactured by Teijin Film Solutions Limited, product name "Purex A70") to a thickness that would result in a 100 μm thick resin layer after drying. Then, it was heated and dried at 105°C for 15 minutes, and a 25 μm thick PET film (manufactured by Toyobo Co., Ltd., product name "Purex A3100") was laminated to the resin layer as a protective film to produce a double-sided PET film-coated resin film (1) (resin film thickness of 100 μm).

[0124] (Preparation of cured resin composition) Two pieces of the double-sided PET film-attached resin film (1) (resin film thickness 100 μm) obtained in each example were cut to a size of 100 mm x 50 mm, and the protective film was peeled off each. The resin films were bonded together using a rubber hand roller (roller size Φ45 x 100 mm) while ensuring that no air bubbles were introduced, and then the rubber hand roller was rolled on a hot plate at 60°C to obtain a double-sided PET film-attached resin film (2) (resin film thickness 200 μm) with a thickness of 200 μm. This resin film (2) was heated in a 180°C oven for 1 hour with the PET film still attached (pre-curing). Next, the PET films on both sides were peeled off, and it was heated in a 200°C oven for 2 hours (post-curing). The following storage modulus, linear thermal expansion coefficient, dielectric constant, and dielectric loss tangent were measured using this cured product.

[0125] (Measurement of Storage Modulus) The cured material obtained in each example (thickness 200 μm) was cut to a size of 30 mm x 5 mm, and the width and thickness were measured using a micrometer to prepare the test specimens. A dynamic viscoelasticity measuring device (Rheogel-E4000, manufactured by UPM Co., Ltd.) was used, and the test specimens were fixed to the tensile measuring jig with a chuck distance of 20 mm. The test conditions were tensile mode, sine wave, frequency 10 Hz, strain control 5 μm automatic control, starting temperature 40 °C, step temperature 2 °C, ending temperature 310 °C, and heating rate 5 °C / min. The width and thickness measured earlier were given as the sample dimensions, and measurements were taken. From the measured viscoelasticity curve, E' at 40 °C was read and taken as the storage modulus.

[0126] (Measurement of Linear Thermal Expansion Coefficient (CTE)) In each example, the hardened material (thickness 200 μm) was cut to a size of 25 mm x 4 mm, and the test piece was clamped at both ends in the long side direction with upper and lower grips, with a gap of 10 mm between the grips. Next, the dimensional change was measured twice consecutively using a thermomechanical measuring device (TMA) (EXSTAR6000, manufactured by Seiko Instruments Inc.) in tensile mode, temperature range 20°C to 260°C, heating rate 10°C / min, and load 49 mN. During the second heating process, the average value of the dimensional change per unit temperature in the ranges of 25°C to 150°C and 150°C to 240°C was defined as CTE1 (25°C to 150°C) and CTE2 (150°C to 240°C).

[0127] (Measurement of Dielectric Constant and Dielectric Loss Tangent) The cured material obtained in each example (thickness 200 μm) was cut to a size of 30 mm x 50 mm, and its thickness was measured with a micrometer to create test specimens. A 10 GHz split-post dielectric resonator (SPDR) was connected to a microwave network analyzer (Keysight Technologies, "N5227B"), and measurements were taken both with and without the test specimen inserted. The calculated Er was defined as the dielectric constant (Dk) at 10 GHz, and the Loss tangent was defined as the dielectric loss tangent (Df). The measurements were performed in an environment of 25°C and 50% humidity.

[0128] The evaluation results for Examples 1 to 8 and Comparative Examples 1 to 3 are shown in Table 2.

[0129]

[0130] Comparative Examples 1 and 2 are conventional resin compositions using epoxy resin combined with an activated ester resin as a curing agent. The resin compositions of Comparative Examples 1 and 2 are prepared based on a method of lowering dielectric properties by using an activated ester resin. Comparing Examples 1 to 8 with Comparative Examples 1 to 2, Examples 1 to 8 have lower dielectric constants and are suitable for use in low-loss printed circuit boards compared to Comparative Examples 1 to 2. Furthermore, Examples 1 to 8 maintain a lower storage modulus despite having a lower linear thermal expansion coefficient (CTE2) at high temperatures compared to Comparative Examples 1 to 2. This allows for stress relief, making it easier to prevent cracking of the glass, for example, when a glass plate is used as the core material.

[0131] Comparative Example 3 is an example in which an un-epoxy modified polyolefin (polybutadiene F-2) is used instead of the specific epoxy-modified polymer in Example 5. Comparing Example 5 with Comparative Example 3, it can be seen that Example 5 has a lower coefficient of linear thermal expansion than Comparative Example 3.

[0132] Furthermore, comparing Examples 2-4 with Example 5, it can be seen that the dielectric loss tangent is reduced in Examples 2-4 by using acid anhydride as a curing agent. In addition, it can be seen that the linear thermal expansion coefficient is lower in Examples 2-4 compared to Example 5.

[0133] Example 6 uses an acid anhydride as a curing agent, but because it does not contain a reactive liquid compound, the amounts of the specific epoxy-modified polymer and acid anhydride are relatively high, resulting in a higher dielectric loss tangent compared to Examples 2-4. However, it is possible to lower the dielectric loss tangent in Example 6 by adjusting the amounts of the specific epoxy-modified polymer and acid anhydride.

[0134] [Comparative Example 4] The components listed in Table 3 were blended in the same manner as in the previous example, and a resin film was manufactured. For comparison with Comparative Example 4, the resin film of Example 3 was prepared.

[0135] [Measurement of Copper Foil Adhesion] The obtained resin film was cut to a size of 40 mm x 40 mm, and after peeling off the protective film, it was attached to a 0.5 mm thick glass plate cut to a size of 50 mm x 50 mm using the rubber hand roller. This was then sandwiched between 50 μm thick PET films and passed through a desktop roll laminator (Lamy Corporation, "Leon 13DX", set temperature 70°C, set speed 6) to press the resin layer to the glass plate. Next, the other PET film was peeled off, and a copper foil cut to 50 mm x 5 mm was placed so that the glossy side was in contact with the resin layer, and another PET film (Purex A70, 25 μm thick) was attached using a hand roller. This was then sandwiched between 50 μm thick PET films and passed through the desktop roll laminator to press the copper foil to the resin layer. This laminate, with the PET film in contact with the resin layer still attached, was heated in a 130°C oven for 30 minutes and then in a 180°C oven for 1 hour. After cooling to room temperature (25°C), the PET film was peeled off. The laminate was then heated again in a 200°C oven for 2 hours to obtain a sample for evaluating the copper foil adhesion strength. Using a Shimadzu Ez Test compact benchtop tester, a 500N load cell, a Φ118 lower disc, and an upper grip were combined to pull the copper foil at a 90-degree angle and a pulling speed of 50 mm / min. The 90-degree peel strength was measured and defined as the copper foil adhesion strength.

[0136] (Evaluation of chemical resistance) The resin film was cut to a size of 40 mm x 40 mm, and after peeling off the protective film, it was attached to a 0.5 mm thick glass plate cut to 50 mm x 50 mm using the rubber hand roller. This was then sandwiched between 50 μm thick PET films and passed through a desktop roll laminator (Lamy Corporation Leon 13DX, set temperature 70°C, set speed 6) to press the resin layer onto the glass plate. This laminate, with the PET film still attached to the resin layer, was heated in a 180°C oven for 1 hour, cooled to room temperature, and then the PET film was peeled off to obtain a sample for chemical resistance evaluation.

[0137] After sequentially treating the samples with the following chemicals under the conditions described, they were rinsed with running water and then heated in a 120°C oven for 30 minutes, and the condition was visually observed. If delamination occurred from the glass substrate, it was considered unresistant; if there was no delamination and no change in appearance, it was considered resistant.

[0138] Swelling treatment: Mixture of 1200 mL of pure water, 6 g of sodium hydroxide, and 1000 mL of Swelling Dip Securigand P (manufactured by Atotec Japan Co., Ltd.). 70°C, 5 minutes. Washing treatment: 1000 mL of pure water. 25°C, 2 minutes. Roughening treatment: Mixture of 720 mL of pure water, 80 g of sodium hydroxide, and 1280 mL of Concentrate Compact CP (manufactured by Atotec Japan Co., Ltd.). 70°C, 15 minutes. Washing treatment: 2000 mL of pure water. 50°C, 2 minutes. Reduction treatment: Mixture of 1700 mL of pure water, 100 mL of concentrated sulfuric acid, and 200 mL of Reduction Solution Securigand P500 (manufactured by Atotec Japan Co., Ltd.). 40°C, 5 minutes.

[0139] (Measurement of Linear Thermal Expansion Coefficient (CTE)) The resin film was cured in the same manner as in the previous example, and the linear thermal expansion coefficient (CTE) was measured in the same manner.

[0140]

[0141] Comparative Example 4 does not use the specific epoxy-modified polymer (A1), but instead uses 1,9-nonanediol dimethacrylate (F-4). As shown in Table 3, Example 3 has a lower linear thermal expansion coefficient CTE2 at high temperatures compared to Comparative Example 4, so it can reduce warping when used as an insulating layer for printed circuit boards. In addition, Example 3 has better resistance in chemical resistance tests with roughening treatment compared to Comparative Example 4, and also has superior adhesion to copper foil. Generally, hole drilling of glass cores is performed by etching using chemicals, so the resin composition of this example is suitable for use in printed circuit boards with glass cores.

[0142] 10 Sheet material 12 Support 14 Insulating layer 20 Circuit board 22 Conductor layer 30 Conductor layer

Claims

1. A resin composition containing an epoxy-modified double-bond-containing hydrocarbon polymer, a thermoplastic elastomer, and an inorganic filler.

2. The resin composition according to claim 1, further comprising a curing agent.

3. The resin composition according to claim 2, wherein the curing agent comprises at least one selected from the group consisting of acid anhydrides and active ester compounds.

4. The resin composition according to claim 3, wherein the acid anhydride comprises at least one selected from the group consisting of a liquid acid anhydride at 25°C, an acid anhydride-modified polybutadiene, and an acid anhydride-modified styrene-ethylene-butylene-styrene block copolymer (SEBS).

5. The resin composition according to claim 1 or claim 2, wherein the thermoplastic elastomer comprises a thermoplastic elastomer having structural units derived from styrene.

6. The resin composition according to claim 1 or claim 2, wherein the thermoplastic elastomer comprises a hydrogenated styrene-based thermoplastic elastomer.

7. The resin composition according to claim 1 or claim 2, wherein the epoxy-modified double-bond-containing hydrocarbon polymer comprises at least one selected from the group consisting of epoxy-modified polybutadiene and epoxy-modified polyisoprene.

8. The resin composition according to claim 1 or claim 2, further comprising a maleimide compound.

9. The resin composition according to claim 8, wherein the maleimide compound comprises at least one selected from the group consisting of a maleimide resin having one or more N-substituted maleimide groups, a maleimide resin containing a condensed ring, and an aliphatic bismaleimide compound.

10. The resin composition according to claim 1 or claim 2, wherein the inorganic filler comprises silica particles.

11. The resin composition according to claim 1 or claim 2, wherein the inorganic filler comprises silica particles having an average particle size of 0.01 μm to 20 μm.

12. A sheet-like material comprising the resin composition according to claim 1 or claim 2.

13. A printed circuit board having a cured product of the resin composition according to claim 1 or claim 2.

14. A semiconductor device having a printed circuit board as described in claim 13.

Images