TW201610067A - Adhesive film - Google Patents

Abstract

The present invention relates to an adhesive film capable of improving magnetic permeability, reducing a loss of magnetic forces, and forming an insulation layer with excellent reliability on an insulating property. The adhesive film has a supporter and a resin composition layer installed on the supporter. The resin composition layer contains components of (A) a thermosetting resin, (B) a magnetic filler, and (C) an inorganic filler. A content of the component (B) is 10 volume% or more, based on 100 volume% of a nonvolatile component in a resin composition forming the resin composition layer. Moreover, a value obtained by dividing the content of the component (C) by the content of the component (B) is 0.3-3.0.

Description

Next film

The present invention relates to a method of manufacturing a film, a wiring board, and a wiring board.

A power inductor, a high-band region inductor, and an inductor element called a common mode choke coil are often mounted on information terminals such as mobile phones and smart phones. At present, the inductor element of the high frequency band region in which the frequency of the operation signal is 1 GHz or more, particularly in the range of 1 GHz to 3 GHz, is known, for example, a winding structure in which a coil is wound around a core member, and a laminated structure in which a coil conductor is laminated on a core member. A wiring layer constituting one of the coils is formed on each of the plurality of layered insulators, and the insulating layers forming the wiring layer are laminated in such a manner that the wiring layers are electrically connected to each other to be squeezed into the thickness of the insulating portion. The film construction of the coil.

In the inductor element for a high-frequency band region, since the Q value is required to be high in characteristics, an air-core coil is generally used, that is, a structure in which the core portion is hollow or filled with a non-magnetic material. However, it is impossible for the high-frequency band region of such a configuration to increase the magnetic permeability of the non-magnetic core portion of the core (in comparison) Since the magnetic permeability is increased, the inductor element is further reduced in size, and the inductance (L value) is lowered when the high frequency band region is activated.

Patent Document 1 discloses that when a thermosetting magnetic slurry containing (A) an alicyclic olefin polymer having a carboxyl group, (B) a thermosetting agent, (C) a magnetic material, and (D) a solvent is used, (C) The magnetic material is excellent in dispersibility, and can contain various components at a high concentration, and can form an electrically insulating layer having excellent properties such as electrical insulating properties, high-frequency characteristics, and magnetic permeability.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2004/29153

In recent years, in order to reduce the size and size of information terminals, the inductor elements for high-band regions have also been required to be thinner and smaller.

In order to further reduce the thickness and size of the inductor element in the high-frequency band region, it is necessary to reduce the number of turns of the coil and to reduce the cross-sectional area of the wiring constituting the coil. In order to reduce the number of turns of the coil and to reduce the sectional area of the wiring constituting the coil, the inductor element of the high-frequency band region of the film structure is advantageous. However, in the inductor element of the high-frequency band region of the film structure, only the number of turns of the coil is simply reduced, and the cross-sectional area of the wiring constituting the coil is made small, and the inductor is lowered. Inductor components for high-band regions of thin film construction The magnetic permeability (μ') of the high insulating layer can increase the L value and the Q value of the inductor element for the high frequency band region. Therefore, it is required to further increase the magnetic permeability of the insulating layer and to reduce the magnetic loss of the material.

However, in the above-described Patent Document 1, when the thermosetting magnetic slurry is used to form an inductor element having a thin film structure, the magnetic loss (μ") particularly in the range of 1 GHz to 3 GHz is increased. The material disclosed in Document 1 is hardly referred to as a material which can be used as an insulating layer (insulating portion) of an inductor element for a high-frequency band region.

The inventors of the present invention have conducted a preliminary review on a resin composition containing a magnetic filler in accordance with the above-mentioned requirements, and have found that the resin composition contains a magnetic filler, and when the resin composition is used to form an insulating layer, there is a frequency of 1 GHz. In the range of up to 3 GHz, the magnetic loss is increased, and the Q value is lowered, and the reliability of insulation is lowered.

The present invention has been made in view of the above problems, and an object thereof is to provide a bonding film which can improve magnetic permeability in a frequency range of 1 GHz to 3 GHz, can reduce magnetic loss, and is excellent in reliability in forming insulation. A resin composition of an insulating layer, and a method of manufacturing a wiring board and a wiring board using the bonding film.

The present invention provides the following [1] to [20].

[1] An adhesive film comprising a support and a resin composition layer provided on the support, wherein the resin composition layer contains a component (A) a thermosetting resin, a component. (B) Magnetic filler and component (C) inorganic filler, and when the nonvolatile content in the resin composition constituting the resin composition layer is 100% by volume, the content of the component (B) is 10% by volume or more. And the content of the component (C) divided by the content of the component (B) is in the range of 0.3 to 3.0.

[2] The adhesive film according to [1], wherein the component (A) is an epoxy resin, and the resin composition further contains an epoxy resin curing agent selected from the group consisting of a phenolic curing agent and a naphthol-based curing agent.

[3] The adhesive film according to [2], wherein the epoxy resin hardener is selected from the group consisting of a cresol-based hardener containing a triazine skeleton and a phenolic hardener containing a triazine skeleton.

[4] The adhesive film according to any one of [1] to [3] wherein the resin composition further contains a thermoplastic resin.

[5] The adhesive film according to any one of [1] to [4] wherein the content of the component (B) in the resin composition is from 10% by volume to 40% by volume, and the content of the component (C) It is 10% by volume to 50% by volume.

[6] The adhesive film according to any one of [1], wherein the content of the component (B) and the component (C) in the resin composition is 20% by volume to 75% by volume in total.

[7] The adhesive film according to any one of [1] to [6] wherein the content of the component (B) in the resin composition is from 10% by volume to 25% by volume.

[8] The adhesive film according to any one of [1], wherein the content of the component (B) in the resin composition is 20% by volume to 25% by volume, and the content of the component (C) is 10% by volume to 25% by volume, and component (B) and component (C) The total content is 30% by volume to 50% by volume.

[9] The adhesive film according to any one of [1] to [8] wherein the component (B) has an average particle diameter of 0.3 μm to 10 μm in the resin composition.

[10] The adhesive film according to any one of [1] to [9] wherein the component (C) has an average particle diameter of from 0.01 μm to 5 μm.

[11] The adhesive film according to any one of [1] to [10] wherein the average particle diameter of the component (B) is larger than the average particle diameter of the component (C).

[12] The adhesive film according to any one of [1] to [11] wherein the component (C) is cerium oxide.

[13] The adhesive film according to any one of [1] to [12] wherein the component (C) is a cerium oxide treated with a surface treating agent.

[14] The adhesive film according to [13], wherein the surface treatment agent is an amino decane-based coupling agent.

[15] The adhesive film according to any one of [1] to [14] wherein, when the cured product is formed, the magnetic permeability is 1.1 or more at a frequency of 1 GHz to 3 GHz, and the frequency is 1 GHz to 3 GHz. The magnetic loss is 0.5 or less.

[16] The adhesive film according to any one of [1] to [15] wherein, when the cured product is formed, the magnetic permeability is 1.2 or more at a frequency of 1 GHz to 3 GHz, and the frequency is 1 GHz to 3 GHz. The magnetic loss is 0.3 or less.

[17] The adhesive film according to any one of [1] to [16], which is used for forming an insulating layer of a wiring board including an inductor element.

[18] A wiring board having the same as any one of [1] to [16] An insulating layer of a cured product of the resin composition layer of the film, and a coil-shaped conductive structure in which at least a portion of the insulating layer is embedded, and an inductor element including the coil-shaped conductive structure The insulating layer extends in the thickness direction and is composed of one of the insulating layers surrounded by the coil-shaped conductive structure.

[19] The wiring board according to [18], wherein the frequency at which the inductor element functions is 1 GHz or more.

[20] A method of manufacturing a wiring board, comprising: an insulating portion including a first insulating layer and a second insulating layer; and a coil-shaped conductive structure in which at least a portion is embedded in the insulating portion, and including An inductor element comprising a coil-shaped conductive structure and a part of the insulating portion, the manufacturing method comprising the steps of: preparing the adhesive film according to any one of [1] to [16], and providing the first a step of forming a core substrate of the wiring layer, a step of laminating the resin composition layer of the adhesive film on the core substrate, and thermally curing the resin composition layer to form a first insulating layer, in the first step a step of forming a via hole in the insulating layer, and performing a roughening treatment on the first insulating layer on which the via hole is formed, forming a second wiring layer on the first insulating layer, and forming the first wiring layer and a step of wiring the through holes in the second wiring layer electrically connected, Further, the adhesive film is laminated on the first insulating layer on which the second wiring layer and the via wiring are formed, and is thermally cured to form the second insulating layer, and the first wiring is formed to include the first wiring a coil-shaped conductive structure in which one of the layers and one of the second wiring layers and the wiring in the through-hole are formed, and a portion of the insulating portion that extends in the thickness direction of the insulating portion and is surrounded by the coil-shaped conductive structure The steps of the aforementioned inductor element.

When the adhesive film of the present invention is used, the magnetic permeability particularly in the range of 1 GHz to 3 GHz can be improved, the magnetic loss can be reduced, and the insulating layer excellent in insulation reliability can be provided, and the simple steps can be A wiring board in which an inductor element for a high-performance high-frequency band region including the insulating layer is extruded is provided.

10‧‧‧ wiring board

20‧‧‧ core substrate (inner circuit board)

20a‧‧‧1st main surface

20b‧‧‧2nd main surface

22‧‧‧through holes

22a‧‧‧Wiring in the through hole

24‧‧‧External terminals

30‧‧‧Insulation

32‧‧‧1st insulation layer

34‧‧‧2nd insulation layer

36‧‧‧through hole

36a‧‧‧Through wiring

40‧‧‧Circular conductive structure

42‧‧‧1st wiring layer

42a‧‧‧ solder pads

44‧‧‧2nd wiring layer

Fig. 1 is a schematic plan view of the wiring board viewed from one side in the thickness direction.

Fig. 2 is a view schematically showing a cut end face of a wiring board cut at a position indicated by a point chain of II-II.

3 is a schematic plan view for explaining a configuration of a first wiring layer in a wiring board.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Moreover, each drawing is a schematic view showing the shape, size, and arrangement of the constituent elements based on the extent to which the invention can be understood. The present invention is not limited by the following description, and various constituent elements can be appropriately modified without departing from the scope of the invention. In the following description, the same components are denoted by the same reference numerals, and the description thereof will not be repeated. Further, the embodiment of the present invention is not limited to the configuration and is manufactured and used in accordance with the configuration of the example.

First, the resin composition used for the film of the present embodiment will be described.

The resin composition contains the resin composition of the component (A) thermosetting resin, the component (B) magnetic filler, and the component (C) inorganic filler, and when the nonvolatile content in the resin composition is 100% by volume, The content of the component (B) is 10% by volume or more, and the content of the component (C) divided by the content of the component (B) is in the range of 0.3 to 3.0.

Hereinafter, the components which can be contained in the resin composition will be specifically described.

(ingredient (A))

The resin composition contains a thermosetting resin as the component (A). Examples of thermosetting resins are exemplified as epoxy resins.

- epoxy resin -

The epoxy resin is exemplified by, for example, bisphenol A type epoxy resin and bisphenol F type. Epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol epoxy resin, naphthol novolac epoxy resin, phenol novolac type epoxy Resin, t-butyl catechol epoxy resin, naphthalene epoxy resin, naphthol epoxy resin, fluorene epoxy resin, glycidylamine epoxy resin, glycidyl ester epoxy resin, Phenolic novolak type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin having butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, and spiro ring Epoxy resin, cyclohexane dimethanol type epoxy resin, naphthalene ether type epoxy resin and trimethylol type epoxy resin. Epoxy resins may be used alone or in combination of two or more.

The epoxy resin preferably contains an epoxy resin having two or more epoxy groups in one molecule. When the non-volatile component of the epoxy resin is 100% by mass, it is preferably at least 50% by mass or more of an epoxy resin having two or more epoxy groups in one molecule. In particular, an epoxy resin having two or more epoxy groups in one molecule and a liquid at a temperature of 20 ° C (hereinafter referred to as "liquid epoxy resin") is preferably contained, and three or more molecules are contained in one molecule. An epoxy group or an epoxy resin which is solid at a temperature of 20 ° C (hereinafter referred to as "solid epoxy resin"). Excellent flexibility can be obtained by using a liquid epoxy resin together with a solid epoxy resin as an epoxy resin.

The liquid epoxy resin is exemplified by, for example, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a phenol novolak type epoxy resin, a bifunctional aliphatic epoxy resin, or a naphthalene type epoxy resin, preferably Bisphenol A type epoxy resin, bisphenol F type epoxy resin, or naphthalene type epoxy resin. Specific examples of the liquid epoxy resin are "HP4032" manufactured by DIC Co., Ltd. "HP4032D", "HP4032SS" (naphthalene epoxy resin), "jER828EL" manufactured by Mitsubishi Chemical Corporation, "jER1007" (bisphenol A epoxy resin), "jER807" (bisphenol F epoxy resin) ), "jER152" (phenol novolak type epoxy resin), "ZX1059" manufactured by Nippon Steel Chemical Co., Ltd. (a mixture of bisphenol A epoxy resin and bisphenol F epoxy resin), "YL7410" (2-functional aliphatic epoxy resin) and the like. These may be used alone or in combination of two or more.

The solid epoxy resin is exemplified by, for example, a crystalline bifunctional epoxy resin, a tetrafunctional naphthalene epoxy resin, a cresol novolac epoxy resin, a dicyclopentadiene epoxy resin, a trisphenol epoxy resin, and naphthalene. Phenolic novolak type epoxy resin, biphenyl type epoxy resin, naphthalene ether type epoxy resin. Specific examples of the solid epoxy resin are "HP-4700", "HP-4710" (4-functional naphthalene type epoxy resin), and "N-690" ("phenol novolac type epoxy" manufactured by DIC Co., Ltd. Resin), "N-695" (cresol novolac type epoxy resin), "HP-7200" (dicyclopentadiene type epoxy resin), "EXA7311", "EXA7311-G3", "HP-6000" "(Nexene ether type epoxy resin), "EPPN-502H" (trisphenol epoxy resin) made by Nippon Kayaku Co., Ltd., "NC7000L" (naphthol novolac resin), "NC3000", "NC3000H", "NC3000L", "NC3100" (biphenyl type epoxy resin), "ESN475" (naphthol novolac type epoxy resin) manufactured by Nippon Steel Chemical Co., Ltd., "ESN485" (naphthol novolac type epoxy) "YX4000H" (Lyrene-based epoxy resin) made of Mitsubishi Chemical Co., Ltd., "YL6121" (biphenyl type epoxy resin), and crystalline 2-functional epoxy resin (YX4000HK) Wait.

When the liquid epoxy resin and the solid epoxy resin are used as the epoxy resin, the ratio (liquid epoxy resin: solid epoxy resin) is preferably 1:0.1 to 1: by mass ratio. 4 range. When the ratio of the amount of the liquid epoxy resin to the solid epoxy resin is within this range, an effect of obtaining a cured product having sufficient fracture strength or the like can be obtained. From the viewpoint of the effect, the ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) is preferably in the range of 1:0.3 to 1:3.5 by mass ratio. It is preferably in the range of 1:0.6 to 1:3, and more preferably in the range of 1:0.8 to 1:2.5.

The content of the non-volatile component of the epoxy resin in the resin composition is preferably from 20% by volume to 60% by volume, more preferably from 22% by volume to 55% by volume, still more preferably from 24% by volume to 53% by volume, It is preferably from 26% by volume to 49% by volume.

The epoxy equivalent of the epoxy resin is preferably in the range of 50 to 3,000, more preferably in the range of 80 to 2,000, and more preferably in the range of 110 to 1,000. By setting it as this range, the cured material with sufficient bridge|crosslinking density can be obtained. Further, the epoxy equivalent can be measured by a method standardized by JIS K7236. Here, the epoxy equivalent is the mass of the epoxy resin containing 1 equivalent of an epoxy group.

(ingredient (B)) -Magnetic filler -

The resin composition contains a magnetic filler as the component (B). Available magnetic The material of the filler is not particularly limited, and examples thereof include pure iron powder, Fe-Si alloy powder, Fe-Si-Al alloy powder, Fe-Ni alloy powder, Fe-Ni-Mo alloy powder, Fe-. Ni-Mo-Cu alloy powder, Fe-Co alloy powder, Fe-Ni-Co alloy powder, Fe-Cr alloy powder, Fe-Cr-Si alloy powder, Fe-Ni-Cr alloy powder, Or Fe alloys such as Fe-Cr-Al alloy powders, amorphous alloys such as Fe-based amorphous and Co-based amorphous, Mg-Zn ferrite, Mn-Zn ferrite, and Mn-Mg fertilizer. Grain iron, Cu-Zn ferrite, Mg-Mn-Sr ferrite, Ni-Zn ferrite, and other spinel ferrites, Ba-Zn ferrite, Ba-Mg Ferritic iron, Ba-Ni ferrite, Ba-Co ferrite, Ba-Ni-Co ferrite, etc., hexagonal crystal ferrite, Y ferrite, iron, etc. class.

As the magnetic filler, a commercially available magnetic filler can be used. Specific examples of commercially available magnetic fillers that can be used are "PST-S" manufactured by Sanyo Special Steel Co., Ltd., "AW2-08PF20F" manufactured by EPSOM ATMIX, "AW2-08PF10F", and "AW2-08PF3F". "Fe-3.5Si-4.5CrPF20F", "Fe-50NiPF20F", "Fe-80Ni-4MoPF20F", "LD-M", "LD-MH", "KNI-106" made by JFE Chemical Co., Ltd. "KNI-106GSM", "KNI-106GS", "KNI-109", "KNI-109GSM", "KNI-109GS", "KNS-415" and "BSF-547" made by Toda Industrial Co., Ltd. BSF-029, BSN-125, BSN-714, BSN-828, S-1281, S-1641, S-1651, S-1470, S -1511", "S-2430", "JR09P2" made by Japan Heavy Chemical Industry Co., Ltd., CIK "Nanotek" manufactured by Nanotek Co., Ltd., "JEMK-S" manufactured by KINSEI MATEC Co., Ltd., "JEMK-H", and "Yttrium iron oxide" manufactured by ALDRICH. The magnetic filler may be used singly or in combination of two or more.

The average particle diameter of the magnetic filler is from 0.3 μm to 10 μm, preferably from 0.3 μm to 7 μm, more preferably from 0.5 μm to 5 μm.

When the nonvolatile content in the resin composition is 100% by volume, the content of the magnetic filler is 10% by volume or more, preferably 10% by volume to 40% by volume, more preferably 10% by volume to 35% by volume, and still more It is preferably from 15% by volume to 30% by volume, preferably from 15% by volume to 25% by volume.

(ingredient (C)) -Inorganic filler -

The resin composition contains an inorganic filler as the component (C). The inorganic filler is usually used to suppress abnormality such as cracks and circuit deformation due to a difference in thermal expansion rate due to a decrease in thermal expansion coefficient when the resin composition is cured, and to suppress excessive decrease in melt viscosity. Further, when a magnetic filler is used, an inorganic filler is not usually coexisted based on the viewpoint of improving characteristics such as magnetic permeability. However, it is aimed at preventing the resin composition in the resin composition or by agglomerating the magnetic filler in the cured product (insulating layer) formed by curing the resin composition, thereby improving the reliability of the insulating property of the resin composition when it is used as a cured product. Inorganic filler materials can be used.

The inorganic filler is exemplified by, for example, cerium oxide, aluminum oxide, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, carbon. Calcium acid, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, barium titanate, calcium titanate, magnesium titanate, barium titanate, titanium oxide, barium zirconate, and calcium zirconate. Among these, cerium oxide such as amorphous cerium oxide, molten cerium oxide, crystalline cerium oxide, synthetic cerium oxide, and hollow cerium oxide is preferred. Further, the cerium oxide is preferably spherical cerium oxide. The inorganic filler may be used singly or in combination of two or more. Commercially available spherical (melted) cerium oxide is exemplified by "SO-C1", "SO-C2", "SO-C4", "SO-C5", and "SO-C6" manufactured by ADMATECHS Co., Ltd., for example.

When the average particle diameter of the inorganic filler is 6 μm or more, the fluidity and the moldability of the resin composition are deteriorated, the magnetic permeability and the magnetic loss at a high frequency when the cured product is formed, and the initial resistance value are deteriorated. The viewpoint of improving the fluidity of the resin composition is preferably in the range of 0.01 μm to 5 μm, more preferably 0.05 μm to 5 μm, still more preferably in the range of 0.05 μm to 2.5 μm, and even more preferably in the range of 0.1 μm to 1.5 μm. The range is preferably in the range of 0.3 μm to 1.0 μm.

The average particle size of the inorganic filler can be determined by the laser diffraction ‧ scattering method based on the Mie scattering theory. Specifically, the laser diffraction scattering type particle size distribution measuring apparatus can be used to prepare the particle size distribution of the inorganic filler on a volume basis, and the median diameter is measured as the average particle diameter. In this case, a measurement sample obtained by dispersing an inorganic filler in water by ultrasonic waves is preferably used. For the laser diffraction scattering type particle size distribution measuring apparatus, "LA-500" manufactured by Horiba, Ltd., etc. can be used.

The inorganic filler is preferably an amine decane coupling agent, an epoxy decane coupling agent, or a sulfhydryl group, from the viewpoint of improving moisture resistance and dispersibility. One or more kinds of surface treatment agents such as a decane coupling agent, a decane coupling agent, an organic decane compound, and a titanate coupling agent are used. The commercially available product of the surface treatment agent is, for example, "KBM403" (3-glycidoxypropyltrimethoxydecane) manufactured by Shin-Etsu Chemical Co., Ltd., and "KBM803" manufactured by Shin-Etsu Chemical Co., Ltd. (3) "Methyl propyl trimethoxy decane", "KBE903" (3-aminopropyltriethoxy decane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573" (N-Benzene) manufactured by Shin-Etsu Chemical Co., Ltd. "Zy-3-aminopropyltrimethoxydecane", "SZ-31" (hexamethyldioxane) manufactured by Shin-Etsu Chemical Co., Ltd., etc.

The inorganic filler surface-treated with the surface treatment agent can be washed by a solvent (for example, methyl ethyl ketone (MEK)), and the amount of carbon per unit surface area of the inorganic filler is measured. Specifically, a sufficient amount of MEK as a solvent was added to the inorganic filler surface-treated with the surface treatment agent, and ultrasonic cleaning was performed at 25 ° C for 5 minutes. Next, the supernatant liquid was removed, and the nonvolatile matter (solid content) was dried, and then the amount of carbon per unit surface area of the inorganic filler was measured using a carbon analyzer. For the carbon analyzer, "EMIA-320V" manufactured by Horiba Ltd. can be used.

The amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg/m ² or more, more preferably 0.1 mg/m ² or more, still more preferably 0.2 mg/m ² , from the viewpoint of improving the dispersibility of the inorganic filler. the above. On the other hand, the amount of carbon per unit surface area of the inorganic filler is preferably 1 mg/m ² or less, more preferably 0.8 mg/m ² or less, still more preferably 0.5 mg/m ² , from the viewpoint of suppressing an increase in melt viscosity. the following.

In the resin composition, the component (B) of the magnetic filler and the inorganic filler The content of the component (C) of the filler is the value of the content of the inorganic filler divided by the content of the magnetic filler (hereinafter referred to as "inorganic filler (component (C)) / magnetic filler (component (B))") Set to a range of 0.3 to 3.0. The inorganic filler/magnetic filler is preferably in the range of 0.4 to 2.7, more preferably in the range of 0.5 to 2.5.

In the resin composition, the content of the component (B) of the magnetic filler and the component (C) of the inorganic filler is preferably from 20% by volume to 75% by volume, more preferably from 20% by volume to 65% by volume, more preferably 22% by volume to 60% by volume, more preferably 24% by volume to 57% by volume.

In the resin composition, the content of the component (B) is preferably from 20% by volume to 25% by volume based on the viewpoint that the magnetic permeability and the magnetic loss when the cured product are formed are in a good range, and the content of the component (C) is 10% by volume to 25% by volume, and the total content of the component (B) and the component (C) is 30% by volume to 50% by volume.

The average particle diameter of the magnetic filler is preferably larger than the average particle diameter of the inorganic filler.

When the content ratio of the magnetic filler and the inorganic filler is as described above, and the average particle diameter of the magnetic filler is larger than the average particle diameter of the inorganic filler, the inorganic filler can be efficiently disposed so as to surround the periphery of the magnetic filler particles. Thereby, the magnetic filler particles can be prevented from aggregating and contacting each other, and the magnetic filler particles can be separated from each other, so that the magnetic filler can be used to increase the magnetic permeability and achieve good insulation.

As a result, when the resin composition of the present embodiment is used as a cured product, the magnetic permeability at a frequency of 1 GHz to 3 GHz can be 1.1 or more, further 1.2 or more, and the frequency can be 1 GHz to 3 GHz. The magnetic loss at this time is 0.5 or less, and further 0.3 or less.

(other ingredients)

The resin composition contains a curing agent for curing the resin composition as another component, and may further contain a component for adjusting the properties of the resin composition or the cured product thereof as needed. Other components are, for example, thermoplastic resins, curing accelerators, flame retardants, and organic fillers, and are exemplified by organometallic compounds such as organic copper compounds, organozinc compounds, and organic cobalt compounds, and tackifiers, defoamers, and modulating agents. A resin additive such as a flat agent, a tackifier, or a coloring agent. Hereinafter, the curing agent, the thermoplastic resin, the curing accelerator, the flame retardant, and the organic filler in the above will be described.

-hardener-

The curing agent is not particularly limited as long as it has a function of curing the component (A) of the thermosetting resin. When the component (A) is an epoxy resin, the hardener is an epoxy resin hardener. The epoxy resin hardener is exemplified by, for example, a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent, a benzoxazine-based curing agent, and a cyanate-based curing agent. The epoxy resin hardener may be used singly or in combination of two or more. The curing agent is preferably a phenol-based curing agent or a naphthol-based curing agent, and more preferably a phenol-based curing agent, from the viewpoint of reliability of insulation and heat resistance.

The phenolic curing agent and the naphthol-based curing agent are, for example, a phenolic curing agent having a novolak structure, a naphthol-based curing agent having a novolak structure, a nitrogen-containing phenol-based curing agent, and a cresol-based curing containing a triazine skeleton. A phenolic hardener containing a triazine skeleton. The phenolic curing agent and the naphthol-based curing agent are preferably a cresol-based curing agent containing a triazine skeleton and a phenol-based curing agent containing a triazine skeleton, and more preferably contain a triazine, from the viewpoint of flame retardancy and reactivity. A phenolic hardener for the skeleton.

Specific examples of the phenolic curing agent and the naphthol-based curing agent are, for example, "MEH-7700", "MEH-7810", "MEH-7851", and "Nippon Chemical Co., Ltd." manufactured by Mingwa Kasei Co., Ltd. "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN375", "SN395", "NHN", "CBN", "GPH", and Dongdu Chemicals Co., Ltd. "LA7052", "LA7054", "LA3018", etc. of DIC (share) system.

The active ester-based curing agent is not particularly limited, and it is generally preferred to use two or more reactive substances such as phenol esters, thiophene esters, N-hydroxylamine esters, and esters of heterocyclic hydroxy compounds. Ester-based compound. The active ester-based curing agent is preferably a curing agent obtained by a condensation reaction of a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxy compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, the active ester-based curing agent obtained from the carboxylic acid compound and the hydroxy compound is more preferably an active ester-based curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound. The carboxylic acid compound is exemplified by, for example, benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid or the like. Phenolic compounds or naphthol compounds are exemplified by, for example, hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methyl Chemical Bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene , 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, benzenetriol, dicyclopentadiene diphenol compound, phenol Novolac and the like.

The active ester-based hardener is specifically exemplified by an active ester compound containing a dicyclopentadiene-type diphenol condensation structure, an active ester compound containing a naphthalene structure, an active ester compound of a phenolic novolac-containing acetal, and a phenol-containing phenol varnish. An active ester compound of benzamidine.

A commercially available product of an active ester-based curing agent is, for example, "EXB9451", "EXB9460", "EXB9460S", "HPC-" manufactured by DIC Co., Ltd. as an active ester compound containing a dicyclopentadiene-type diphenol condensation structure. 8000-65T", the active ester compound containing a naphthalene structure is exemplified by "EXB9416-70BK" manufactured by DIC Co., Ltd., and the active ester compound of acetal containing phenol novolac is exemplified by "DC808" manufactured by Mitsubishi Chemical Corporation. The active ester compound of the phenformin containing phenol novolac is exemplified by "YLH1026" manufactured by Mitsubishi Chemical Corporation.

Specific examples of the benzoxazine-based curing agent are, for example, "HFB2006M" manufactured by Showa Polymer Co., Ltd., and "P-d" and "F-a" manufactured by Shikoku Chemical Industries Co., Ltd.

Cyanate-based hardeners are exemplified by, for example, bisphenol A diisocyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene), 4,4'-methylene Bis(2,6-dimethylphenyl cyanate), 4,4'-ethylene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4- Cyanate ester Alkane, 1,1-bis(4-cyanate phenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanate benzene) 2-functional cyanate resin such as keto-1-(methylethylidene) benzene, bis(4-cyanate phenyl) sulfide, and bis(4-cyanate phenyl) ether, from phenol A polyfunctional cyanate resin derived from a novolac and a cresol novolak, or a prepolymer which is a triazine-formed part of the cyanate resin. Specific examples of the cyanate-based curing agent are "PT30" and "PT60" (all phenol novolac type polyfunctional cyanate resins) manufactured by LONZA Co., Ltd., and "BA230" (bisphenol A diisocyanate). Part or all of the prepolymer of the triazineated terpolymer) and the like.

The ratio of the epoxy resin to the epoxy resin hardener is preferably 1:0.2 as the ratio of [the total number of epoxy groups of the epoxy resin]: [the total number of reactive groups of the epoxy resin hardener]. The range of 1:2 is preferably in the range of 1:0.3 to 1:1.5, and more preferably in the range of 1:0.4 to 1:1. Here, the reactive group of the epoxy resin curing agent is an active hydroxyl group, an active ester group, or the like, and varies depending on the type of the curing agent. Further, the total number of epoxy groups of the epoxy resin is a total of values obtained by dividing the mass of the nonvolatile component of each epoxy resin by the equivalent of the epoxy equivalent for all the epoxy resins, and the so-called epoxy resin hardener The total number of reactive groups is a total value obtained by dividing the mass of the nonvolatile component of each epoxy resin hardener by the equivalent of the reactive base for all the epoxy resin hardeners. When the ratio of the epoxy resin to the epoxy resin hardener is within this range, the heat resistance at the time of becoming a cured product can be further improved.

Regarding the content of the epoxy resin hardener, the ratio of the total number of epoxy groups of the epoxy resin to the total number of reactive groups of the epoxy resin hardener, It is preferably in the range of 1:0.2 to 1:2, more preferably in the range of 1:0.3 to 1:1.5, and more preferably in the range of 1:0.4 to 1:1.

The resin composition preferably contains a mixture of a liquid epoxy resin as an epoxy resin and a solid epoxy resin (liquid epoxy resin: solid epoxy resin mass ratio, preferably 1:0.1 to 1: The range of 4 is preferably in the range of 1:0.3 to 1:3.5, and more preferably in the range of 1:0.6 to 1:3, preferably in the range of 1:0.8 to 1:2.5), which is hardened as an epoxy resin. One or more selected from the group consisting of a phenolic curing agent, a naphthol-based curing agent, an active ester-based curing agent, and a dicyanate-based curing agent (preferably, a phenolic curing agent or a naphthol-based curing agent) One or more selected from the group consisting of a phenol novolac resin containing a triazine skeleton and a naphthol-based curing agent, and more preferably one or more containing a triazine skeleton. Epoxy resin hardener for phenol novolac resin).

- Thermoplastic Resin -

The thermoplastic resin is exemplified by, for example, a phenoxy resin, an acrylic resin, a polyvinyl acetal resin, a polyimide resin, a polyamidoximine resin, a polyether oxime resin, and a polyfluorene resin. The thermoplastic resin may be used singly or in combination of two or more.

The weight average molecular weight of the thermoplastic resin in terms of polystyrene is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and more preferably in the range of 20,000 to 60,000. The polystyrene-equivalent weight average molecular weight of the thermoplastic resin is measured by a gel permeation chromatography (GPC) method. Specifically, the polystyrene-converted weight of the thermoplastic resin is flat. "Shodex K-800P/K-804L/K-804L" manufactured by Showa Denko Co., Ltd. is used as a pipe column, and "LC-9A/RID-6A" manufactured by Shimadzu Corporation is used as a measuring device. Using chloroform or the like as a mobile phase, the column temperature was measured at 40 ° C, and it was calculated using a calibration line of standard polystyrene.

The phenoxy resin is exemplified by, for example, having a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a bisphenol acetophenone skeleton, a novolac skeleton, a biphenyl skeleton, an anthracene skeleton, a dicyclopentadiene skeleton, and a norbornene. A phenoxy resin having one or more kinds of skeletons selected from the group consisting of an olefin skeleton, a naphthalene skeleton, an anthracene skeleton, an adamantane skeleton, a terpene skeleton, and a trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. The phenoxy resin may be used singly or in combination of two or more. Specific examples of the phenoxy resin are "1256" and "4250" (all are phenoxy resins containing a bisphenol A skeleton) and "YX8100" (a phenoxy resin containing a bisphenol S skeleton) manufactured by Mitsubishi Chemical Corporation. And "YX6954" (phenoxy resin containing bisphenol acetophenone skeleton), and "FX280" and "FX293" manufactured by Dongdu Chemical Co., Ltd., and "YL7553" manufactured by Mitsubishi Chemical Corporation. YL6794", "YL7213", "YL7290" and "YL7482".

The acrylic resin is preferably an acrylic resin containing a functional group, and more preferably an epoxy group-containing acrylic resin having a glass transition temperature of 25 ° C or less, from the viewpoint of further lowering the coefficient of thermal expansion and the modulus of elasticity.

The number average molecular weight (Mn) of the functional group-containing acrylic resin is preferably from 10,000 to 1,000,000, more preferably from 30,000 to 900,000.

The functional group equivalent of the functional group-containing acrylic resin is preferably from 1,000 to 50,000, more preferably from 2,500 to 30,000.

The epoxy group-containing acrylic resin having a glass transition temperature of 25 ° C or less is preferably an epoxy group-containing acrylate copolymer resin having a glass transition temperature of 25 ° C or less, and specific examples thereof are "SG" manufactured by Nagase Chemtex Co., Ltd. -80H" (epoxy group-containing acrylate copolymer resin (number average molecular weight Mn: 350,000 g/mol, epoxy price: 0.07 eq/kg, glass transition temperature: 11 ° C), and "SG-P3" manufactured by Nagase Chemtex Co., Ltd. (Epoxy group-containing acrylate copolymer resin (number average molecular weight Mn: 850,000 g/mol, epoxy price 0.21 eq/kg, glass transition temperature: 12 ° C)).

Specific examples of the polyethylene acetal resin are electrochemical butadiene "4000-2", "5000-A", "6000-C", "6000-EP", and Sekisui Chemical Industry Co., Ltd. S-LEC BH series, BX series, "KS-1" and other KS series, BL series, BM series, etc.

Specific examples of the polyimine resin are "RIKACOAT SN20" and "RIKACOAT PN20" manufactured by Nippon Chemical and Chemical Co., Ltd. Specific examples of the polyimine resin include a linear polyimine obtained by reacting a bifunctional hydroxyl-terminated polybutadiene, a diisocyanate compound, and a tetrabasic acid anhydride (Japanese Patent Laid-Open Publication No. Hei. No. 2006-37083). Poly-imine resin), a polyfluorene-containing polyamine (polyimide resin described in JP-A-2002-210667, JP-A-2000-319386, etc.) Yttrium.

Specific examples of polyamidoximine resins are listed as Dongyang Textile "VYLOMAX HR11NN" and "VYLOMAX HR16NN". Specific examples of the polyamidoximine resin include modified polyamidoquinone imines such as "KS9100" and "KS9300" manufactured by Hitachi Chemical Co., Ltd., which is a polyamine oxide skeleton containing a polyoxyalkylene skeleton. .

Specific examples of the polyether oxime resin are "PES5003P" manufactured by Sumitomo Chemical Co., Ltd., and the like.

Specific examples of the polybenzazole resin are "P1700" and "P3500" manufactured by SOLVAY ADVANCE POLYMERS Co., Ltd.

The content of the thermoplastic resin in the resin composition is preferably from 0.1% by mass to 20% by mass. When the content of the thermoplastic resin is within this range, the viscosity of the resin composition can be made moderate, and a resin composition layer having a uniform thickness or overall properties can be formed.

- hardening accelerator -

The hardening accelerator is exemplified by, for example, a phosphorus-based curing accelerator, an amine-based curing accelerator, an imidazole-based curing accelerator, and an oxime-based curing accelerator.

Phosphorus-based hardening accelerators are exemplified by, for example, triphenylphosphine, strontium borate compound, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonate, (4-methyl Phenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and the like.

The amine-based hardening accelerator is exemplified by a trialkylamine such as triethylamine or tributylamine, 4-dimethylaminopyridine (DMAP), benzyldimethylamine, 2,4,6-gin (dimethylamine). Methyl)phenol, 1,8-diazabicyclo(5,4,0)-edecyl Alkene and the like.

The imidazole-based hardening accelerator is exemplified by, for example, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole ( 2E4MZ), 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-1-phenylimidazole, 1-cyanoethyl-2 -methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-methyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole , 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-dicyano-6 -[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')] -ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2, 4-Diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazolium isocyanuric acid adduct, 2 -phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzene Imidazole, 1-dodecyl-2-methyl-3-benzylimidazolium Compound, 2-imidazoline, 2-phenyl imidazole compounds, and imidazoline adducts of an imidazole compound with an epoxy resin composition.

The lanthanide hardening accelerator is exemplified by, for example, dicyandiamide, 1-methyl hydrazine, 1-ethyl hydrazine, 1-cyclohexyl hydrazine, 1-phenyl fluorene, 1-(o-tolyl) fluorene, and dimethyl Base, diphenyl hydrazine, trimethyl hydrazine, tetramethyl hydrazine, pentamethyl hydrazine, 1,5,7-triazabicyclo[4.4.0]non-5-ene, 7-methyl-1 ,5,7-triazabicyclo[4.4.0]non-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1, 1-Dimethyl biguanide, 1,1-diethyl biguanide, 1-cyclohexyl biguanide, 1-allyl biguanide, 1-phenyl double 胍, 1-(o-tolyl)biguanide, and the like.

The curing accelerator may be used singly or in combination of two or more. When the total amount of the non-volatile components of the epoxy resin and the epoxy resin curing agent is 100% by mass, the content of the curing accelerator in the resin composition is preferably from 0.05% by mass to 3% by mass.

- Flame retardant -

The flame retardant is exemplified by, for example, an organic phosphorus-based flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a polyoxygenated flame retardant, a metal hydroxide, or the like. An example of a flame retardant that can be used is "HCA-HQ-HST" manufactured by Sanko Co., Ltd. The flame retardant may be used singly or in combination of two or more. The content of the flame retardant in the resin composition layer is not particularly limited, but is preferably in the range of 0.5% by mass to 10% by mass, more preferably in the range of 1% by mass to 9% by mass, and still more preferably 1.5% by mass. ~8 mass% range.

-Organic filler -

The resin composition preferably contains an organic filler based on the viewpoint of improving the adhesion to the layer formed by the plating step. Examples of organic fillers are exemplified by rubber particles. The rubber particles of the organic filler are, for example, rubber particles which are not dissolved in an organic solvent to be described later and which are incompatible with an epoxy resin, a curing agent, a thermoplastic resin or the like which will be described later. The rubber particles are generally prepared in a particulate form such that the molecular weight of the rubber particle component is so large that it is not dissolved in the organic solvent or the resin.

Rubber particles of organic fillers are listed, for example, as core-shell rubber Glue particles, crosslinked acrylonitrile butadiene rubber particles, crosslinked styrene butadiene rubber particles, acrylic rubber particles, and the like. The core-shell type rubber particles are rubber particles having a core layer and a shell layer, and are exemplified by a two-layer structure in which a shell layer of an outer layer is a glassy polymer, a core layer of an inner layer is a rubbery polymer, or a shell of an outer layer. The layer is composed of a glassy polymer, the intermediate layer is composed of a rubbery polymer, and the core layer of the inner layer is a rubber particle having a three-layer structure composed of a glassy polymer. The glassy polymer layer is composed of, for example, a methyl methacrylate polymer or the like, and the rubbery polymer layer is composed of, for example, a butyl acrylate polymer (butyl rubber) or the like. An example of the rubber particles that can be used is "STAFYROID AC3816N" manufactured by GANTZ Co., Ltd. The rubber particles may be used singly or in combination of two or more.

The average particle diameter of the rubber particles of the organic filler is preferably in the range of 0.005 μm to 1 μm, more preferably in the range of 0.2 μm to 0.6 μm. The average particle diameter of the rubber particles can be measured by dynamic light scattering. For example, the rubber particles can be uniformly dispersed in a suitable organic solvent by ultrasonic waves or the like, and a particle size distribution of rubber particles can be prepared on a mass basis using a thick particle size analyzer ("FPAR-1000" manufactured by Otsuka Electronics Co., Ltd.). The value diameter is measured as the average particle diameter.

The resin composition of the present embodiment is excellent in fluidity when the insulating layer is formed, and is excellent in the sealing property of the wiring layer when the insulating layer (cured material) is formed. Further, when the insulating layer is formed using the resin composition of the present invention, the magnetic permeability in the high frequency band (gigahertz band) having a frequency of 1 GHz or more, particularly in the range of 1 GHz to 3 GHz, can be improved, and the magnetic loss can be suppressed.

The insulating layer formed using the resin composition of the present embodiment has excellent reliability of insulation. The reliability of the insulating property can be evaluated by, for example, lowering the insulation resistance value after being left in an environment of 130 ° C and a relative humidity of 85% for 100 hours (after HAST 100 hours). Specifically, when the insulation resistance value of the insulating layer after 100 hours of HAST exceeded a value of 1.0 × 10 ⁶ Ω, it was evaluated that the reliability of insulation was excellent.

Therefore, the resin composition of the present embodiment can be used as a material for providing an insulating layer of a wiring board of an inductor element of a so-called thin film structure in which a coil is extruded in a thickness of an insulating layer (an insulating portion in which a plurality of insulating layers are laminated).

Next, a film for using the resin composition of the present embodiment and a manufacturing step thereof will be described.

(following the film)

Next, the film contains an organic support and a resin composition layer provided on one main surface of the organic support.

(organic support)

The material of the organic support is exemplified by polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), and polymethyl methacrylate (PMMA). Such as acrylic acid, cyclic polyolefin, triethyl fluorenyl cellulose (TAC), polyether thioether (PES), polyether ketone, polyimine, and the like.

The organic support preferably uses an organic support having a high glass transition temperature (Tg). The glass transition temperature of the organic support is preferably 100 ° C. on.

The material of the organic support having a glass transition temperature of 100 ° C or higher is exemplified by a polyester such as polyethylene naphthalate (PEN), a polycarbonate (PC), or a polymethyl methacrylate (PMMA). Polyolefin, triethyl fluorenyl cellulose (TAC), polyether thioether (PES), polyether ketone, polyether ether ketone, polyimine, and the like. Among them, polyethylene naphthalate and polyimide are preferred from the viewpoint of heat resistance.

In the organic support containing the above-mentioned material, the surface to be bonded to the resin composition layer described later may be subjected to matting treatment or corona treatment.

Further, the organic support may be attached to the side of the resin composition layer, that is, the organic support having the release layer on the side of the coating resin composition (hereinafter, the mold release layer is attached). The organic support of the layer is simply referred to as an organic support). The release agent used for forming the release layer of the organic support having the release layer is, for example, one or more selected from the group consisting of an alkyd resin, a polyolefin resin, a urethane resin, and a polyoxymethylene resin. Release agent. The release layer can be formed, for example, by applying a solution containing a release agent to the surface of the organic support and drying.

The "SK-1" manufactured by LINTEC Co., Ltd., which is a PET film having a release layer containing an alkyd-based release agent as a main component, may be used as the organic support having the release layer. "AL-5", "AL-7", etc.

The thickness of the organic support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, more preferably in the range of 10 μm to 60 μm, and still more preferably in the range of 12.5 μm to 55 μm. Also, use the organic support with the release layer In the case of the body, the thickness of the entire organic support having the release layer is preferably within the above range.

(resin composition layer)

The thickness of the resin composition layer is not particularly limited. The thickness of the resin composition layer is preferably from 0.5 μm to 80 μm, more preferably from 10 μm to 60 μm.

(following the film formation step)

The resin composition used for the resin composition layer can be appropriately mixed with the aforementioned components, and if necessary, by kneading means (3-axis roll, ball mill, bead mill, sand mill, etc.) or stirring means (super kneading machine) , planetary mixers, etc.) are mixed or mixed to prepare.

The method for producing the adhesive film having the resin composition layer is not particularly limited, and the resin paint can be prepared by dissolving the resin composition in an organic solvent, for example, and applying the resin paint to the resin paint using a die coater or the like. The coating film of the applied resin varnish is dried and produced on the organic support.

The organic solvent used in the preparation of the resin paint may, for example, be a ketone such as acetone, methyl ethyl ketone or cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate. Acetates such as esters and carbitol acetates, carbitols such as cellosolve and butyl carbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamidine A guanamine-based solvent such as an amine or N-methylpyrrolidone. The organic solvent may be used singly or in combination of two or more.

The drying treatment of the coating film formed of the resin paint in the formation of the resin composition layer can be carried out by any appropriate drying method known in the art such as heating or blowing hot air. By this drying treatment, the coating film becomes a resin composition layer.

The drying conditions of the drying treatment may be any suitable conditions in consideration of the boiling point of the organic solvent contained in the resin composition or the resin paint. The drying conditions may be, for example, about 3 minutes to 15 minutes at 80 ° C to 150 ° C.

Next, the step of forming the film is preferably carried out by using a strip-shaped support of the organic support in the form of a roll-to-roll method, or in a batch manner.

The film forming step in the roll-to-roll mode can be specifically carried out by: continuously conveying the elongated strip-shaped organic support between at least two rolls including the take-up roll and the take-up roll, and winding the roll A resin film is applied to one main surface of the support body exposed between the winding rolls to form a coating film, and the obtained coating film is continuously dried to form a resin composition layer.

According to this, an adhesive film provided with a resin composition layer on the organic support can be prepared.

When the film is temporarily stored, it is preferable to provide a protective film which is bonded to the exposed surface of the resin composition layer which is not bonded to the organic support (that is, the surface opposite to the organic support). This protective film contributes to prevention of adhesion or scratches of dirt or the like of the resin composition layer. As the protective film, for example, a polypropylene film, a polyethylene film, or the like can be used. And can be used A film made of the same material as the material of the organic support. The thickness of the protective film is not particularly limited and is, for example, 1 μm to 40 μm. The thickness of the protective film is preferably thinner than the thickness of the organic support.

The bonding of the protective film to the adhesive film can be carried out using a conventional laminating apparatus.

The wiring board and the method of manufacturing the same according to the embodiment manufactured using the above-described adhesive film will be described.

[wiring board]

A configuration example of the wiring board will be described with reference to Figs. 1, 2, and 3. Fig. 1 is a schematic plan view as seen from one side in the thickness direction of the wiring board. Fig. 2 is a view showing a cut end face of a wiring board cut at a position indicated by a point chain of II-II. 3 is a schematic plan view for explaining a configuration of a first wiring layer in a wiring board.

The wiring board includes an insulating layer having a cured product of a resin composition (resin composition layer), and a coil-shaped conductive structure in which at least a part of the insulating layer is embedded, and the coil-shaped conductive structure and the insulating layer are An inductor element composed of a portion of the insulating layer extending in the thickness direction and surrounded by the coil-shaped conductive structure.

The frequency at which the inductor element included in the wiring board of the present embodiment can function is estimated to be 1 GHz or more. The frequency at which the inductor element can function is preferably from 1 GHz to 3 GHz.

As shown in FIGS. 1 and 2, the wiring board 10 is a so-called build-up wiring board having a build-up insulating layer. The wiring board 10 is provided with a core substrate 20. core The base material 20 has a first main surface 20a and a second main surface 20b that face each other. The core substrate 20 is an insulating substrate. The core substrate 20 may be a so-called inner layer circuit substrate in which wiring or the like is extruded in the thickness thereof.

Examples of the material of the core substrate 20 are an insulating substrate such as a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, or a thermosetting polyphenylene ether substrate.

The core substrate 20 has a first wiring layer 42 provided on the first main surface 20a and an external terminal 24 provided on the second main surface 20b. The first wiring layer 42 and the second wiring layer 44 include a plurality of wirings. The example of the figure shows only the wiring of the coil-shaped conductive structure 40 constituting the inductor element. The external terminal 24 is a terminal for electrically connecting to an external device or the like (not shown). The external terminal 24 can be configured as a portion of the wiring layer provided on the second main surface 20b.

The conductor material which can form the first wiring layer 42, the second wiring layer 44, the external terminal 24, and other wirings is, for example, gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten. One or more metals selected from the group consisting of iron, tin, and indium. The first wiring layer 42, the second wiring layer 44, the external terminal 24, and other wirings may be made of a single metal or may be made of an alloy, and the alloy may be an alloy of two or more kinds of metals selected from the above group (for example, a nickel-chromium alloy). , copper-nickel alloy and copper-titanium alloy). Among them, based on the viewpoints of versatility, cost, ease of patterning, etc., it is preferred to use chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or nickel-chromium alloy, copper-nickel alloy, copper-titanium. Alloys, better use of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or nickel-chromium alloys, and better use of copper.

The first wiring layer 42 , the second wiring layer 44 , the external terminal 24 , and other wirings may have a single layer structure, or may be formed by laminating two or more single metal layers or alloy layers made of different types of metals or alloys. The layered structure. When the first wiring layer 42, the second wiring layer 44, the external terminal 24, and other wirings have a multi-layer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc or titanium, or an alloy layer of a nickel-chromium alloy. .

The thickness of the first wiring layer 42, the second wiring layer 44, the external terminal 24, and other wirings depends on the design of the desired multilayer printed wiring board, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

The thickness of the first wiring layer 42 and the external terminal 24 included in the core substrate 20 is not particularly limited. The thickness of the first interconnect layer 42 and the external terminal 24 is preferably 70 μm or less, more preferably 60 μm or less, still more preferably 50 μm or less, still more preferably 40 μm or less, and most preferably 30 μm or less and 20 μm from the viewpoint of thinning. Hereinafter, it is 15 μm or less or 10 μm or less. The lower limit of the thickness of the external terminal 24 is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, and still more preferably 5 μm or more.

The ratio of the line (L)/interval (S) of the first interconnect layer 42 and the external terminal 24 is not particularly limited. However, from the viewpoint of reducing the surface unevenness and obtaining an insulating layer having excellent smoothness, it is usually 900/900 μm or less, preferably It is 700/700 μm or less, more preferably 500/500 μm or less, still more preferably 300/300 μm or less, and even more preferably 200/200 μm or less. The lower limit of the line/space ratio is not particularly limited, but is preferably 1/1 μm or more from the viewpoint that the resin composition is excellent in the embedding of the interval.

The core substrate 20 is exemplified by, for example, a glass cloth substrate epoxy tree. "R1515A" manufactured by Panasonic Co., Ltd., which is a double-sided copper-clad laminate, is formed into a wiring layer of a wiring layer by patterning a copper layer.

The core base material 20 has a plurality of through holes 22 that penetrate the core base material 20 from the first main surface 20a to the second main surface 20b. A through-hole inner wiring 22a is provided in the through hole 22. The through-hole wiring 22a electrically connects the first wiring layer 42 and the external terminal 24.

As shown in FIG. 3, the first interconnect layer 42 includes a spiral-shaped wiring portion for forming the coil-shaped conductive structure 40, and a rectangular pad 42a electrically connected to the through-hole wiring 22a. In the illustrated example, the spiral-shaped wiring portion includes a linear portion and a bent portion bent at a right angle and a bypass portion around the bonding pad 42a. In the example of the first wiring layer 42, the outline of the spiral wiring portion of the first wiring layer 42 has a substantially rectangular shape, and has a shape that is wound counterclockwise from the center side toward the outer side.

The first main surface 20a side of the core substrate 20 on which the first wiring layer 42 is provided is provided with the first insulating layer 32 so as to cover the first wiring layer 42 and the first main surface 20a exposed from the first wiring layer 42.

Since the first insulating layer 32 is a layer of the film which is described by the source itself, the first wiring layer 42 is excellent in sealing property. Further, since the first insulating layer 32 is formed using the above-described adhesive film, the magnetic permeability in the high frequency band (gigahertz band) having a frequency of 1 GHz or more, particularly in the range of 1 GHz to 3 GHz, is improved, and magnetic loss is suppressed.

The first insulating layer 32 is provided with a through hole 36 through which the first insulating layer 32 penetrates in the thickness direction.

The second wiring layer 44 is provided on the first insulating layer 32. 2nd match The wire layer 44 includes a spiral-shaped wiring portion for constituting the coil-shaped conductive structural body 40. In the illustrated example, the spiral-shaped wiring portion includes a linear portion and a curved portion bent at right angles. In the example of the present invention, the outline of the spiral wiring portion of the second interconnect layer 44 has a substantially rectangular shape and has a shape that is wound counterclockwise from the center side toward the outer side.

A through-hole inner wiring 36a is provided in the through hole 36. One end of the center side of the spiral wiring portion of the second interconnect layer 44 is electrically connected to one end of the center side of the spiral wiring portion of the first wiring layer 42 by the through-hole wiring 36a. The other end of the spiral side wiring portion of the second interconnect layer 44 is electrically connected to the pad 42a of the first interconnect layer 42 via the via inner wiring 36a. Therefore, the other end of the spiral-shaped wiring portion of the second interconnect layer 44 is electrically connected to the external terminal 24 via the via inner wiring 36a, the pad 42a, and the through-hole wiring 22a.

The coil-shaped conductive structure 40 is a spiral-shaped wiring portion of a portion of the first wiring layer 42 and a spiral-shaped wiring portion of a portion of the second wiring layer 44, and a spiral shape of the first wiring layer 42. The wiring portion is formed by the through-hole wiring 36a electrically connected to the spiral wiring portion of the second wiring layer 44.

The second insulating layer 34 is provided in the first insulating layer 32 in which the second interconnect layer 44 is provided so as to cover the second interconnect layer 44 and the first insulating layer 32 exposed from the second interconnect layer 44.

Similarly to the first insulating layer 32, the second insulating layer 34 is a layer of the film which is described by the source itself. Then, the resin composition layer of the film is excellent in fluidity when the insulating layer is formed, so that the sealing property of the second wiring layer 44 is excellent. different. Further, since the second insulating layer 34 is formed using the above-described adhesive film, the magnetic permeability in the high frequency band of 1 GHz or higher, particularly in the range of 1 GHz to 3 GHz, is improved, and the magnetic loss is suppressed.

The first insulating layer 32 and the second insulating layer 34 constitute an insulating portion 30 which can be regarded as an integral insulating layer. Therefore, the coil-shaped conductive structure 40 is provided so that at least a part of the coiled conductive structure 40 is buried in the insulating portion 30. In the wiring board 10 of the present embodiment, the inductor element is formed of the coil-shaped conductive structure 40 and the insulating portion 30 which is extended in the thickness direction of the insulating portion 30 and surrounded by the coil-shaped conductive structure 40. A part of the core is formed.

In the present embodiment, the coil-shaped conductive structure 40 includes two wiring layers of the first wiring layer 42 and the second wiring layer 44. However, three or more wiring layers (and three or more layers of insulating layers) may be used. The layer) constitutes a coil-shaped conductive structure 40. In this case, the spiral wiring portion of the wiring layer (not shown) disposed between the wiring layer of the uppermost layer and the wiring layer of the lowermost layer is vortexed at one end and the wiring layer disposed closest to the uppermost layer side. Either end portion of the rolled wiring portion is electrically connected, and the other end is electrically connected to either end portion of the spiral wiring portion of the wiring layer disposed closest to the lowermost layer side.

According to the circuit board of the present embodiment, since the insulating layer is formed by the adhesive film, the magnetic permeability of the formed insulating layer can be improved, and as a result, the L value and the Q value of the inductor element extruded into the circuit board can be improved.

[Manufacturing method of wiring board]

Hereinafter, a method of manufacturing the wiring board according to the embodiment will be described. 2 to explain.

The method for manufacturing a wiring board according to the present embodiment includes an insulating portion including a first insulating layer and a second insulating layer, and a coil-shaped conductive structure in which at least a portion is embedded in the insulating portion, and includes a coil-shaped conductive body. In the method of manufacturing a wiring board of an inductor element comprising one of a structural structure and an insulating portion, the present embodiment includes the steps of: preparing a subsequent film and a core substrate provided with the first wiring layer; a step of laminating the resin composition layer on the core substrate, thermally curing the resin composition layer to form the first insulating layer, forming a through hole in the first insulating layer, and forming a through hole a step of roughening the insulating layer, forming a second wiring layer on the first insulating layer, and forming a wiring in the via hole electrically connecting the first wiring layer and the second wiring layer, and further implementing the embodiment The adhesive film is laminated on the first insulating layer on which the second wiring layer and the via wiring are formed, and is thermally cured to form a second insulating layer, and includes a portion including the first wiring layer and the second portion. One part of the wiring layer The through-hole of the coiled conductive wire structure, and a step of extending a portion of the inductor element surrounds the insulating portion of a coil-shaped conductive structure in the thickness direction of the insulating portion.

First, as described above, the first wiring layer 42 provided on the first main surface 20a, the external terminal 24 provided on the second main surface 20b, the through hole 22, and the through-hole wiring 22a are prepared. Core substrate (inner layer circuit substrate) 20 and subsequent film.

(Step of forming the first insulating layer)

Next, the first insulating layer 32 is formed. First, a lamination step of laminating the resin composition layer of the film in contact with the first wiring layer 42 of the core substrate is performed.

The conditions of the laminating step are not particularly limited, and conventional conditions used in forming an insulating layer (addition insulating layer) using a film may be employed. For example, it can be carried out by pressing a metal plate such as a heated stainless steel mirror panel from the side of the organic support of the film. In this case, in order to prevent the unevenness of the surface of the core base material 20 so as not to directly press the metal plate, it is preferable to press the elastic member made of a heat-resistant rubber or the like. The pressing temperature is preferably in the range of 70 ° C to 140 ° C, and the pressing pressure is preferably in the range of 1 kgf / cm ² to 11 kgf / cm ² (0.098 MPa to 1.079 MPa), and the pressing time is preferably 5 seconds to 3 minutes. The scope.

Further, the laminating step is preferably carried out under reduced pressure of 20 mmHg (26.7 hPa) or less. The lamination step can be carried out using a commercially available vacuum laminator. Commercially available vacuum laminating machines are, for example, vacuum press laminators manufactured by Nippon Seisakusho Co., Ltd., vacuum coaters manufactured by NICHIGO MORTON Co., Ltd., and the like.

After the lamination step is completed, a smoothing step of heating and pressurizing the film which is laminated on the core substrate 20 may be carried out.

The smoothing step is generally carried out by a heated metal sheet or a metal roll under normal pressure (atmospheric pressure) by heat and pressure treatment of a film which is laminated on the core substrate 20. The conditions of the heating and pressurization treatment may be the same as those of the above-mentioned lamination step.

The same vacuum layer can also be used for the lamination step and the smoothing step The machine is continuously operated.

Further, the step of peeling off the organic support derived from the film is carried out at any point after the lamination step or the smoothing step. The step of peeling off the organic support can be carried out mechanically using, for example, a commercially available automatic peeling device.

Next, a thermal hardening step of thermally curing the resin composition layer laminated on the core substrate 20 to form an insulating layer (addition insulating layer) is carried out.

The conditions of the heat hardening step are not particularly limited, and the conditions generally employed in forming the insulating layer of the multilayer printed wiring board can be used.

The conditions of the heat hardening step can be set to any preferable conditions depending on the composition of the resin composition used for the resin composition layer and the like. The curing step may be, for example, a curing temperature of 120 ° C to 240 ° C (preferably in the range of 150 ° C to 210 ° C, more preferably in the range of 170 ° C to 190 ° C), and a hardening time of 5 The range of minutes to 90 minutes (preferably 10 minutes to 75 minutes, preferably 15 minutes to 60 minutes).

The step of preheating the resin composition layer at a temperature lower than the curing temperature may be carried out before the thermal hardening step. Before the thermal hardening step, the resin composition layer may be preheated for, for example, 50 ° C or more and less than 120 ° C (preferably 60 ° C or more and 110 ° C or less, more preferably 70 ° C or more and 100 ° C or less) for 5 minutes or more (preferably 5 minutes to 150 minutes, preferably 15 minutes to 120 minutes). The preheating is preferably carried out under atmospheric pressure (at normal pressure).

The first insulating layer 32 provided on the core substrate 20 can be formed by the above steps. Moreover, the lamination step, the thermal curing step, and the wiring described later are repeated one or more times on the core substrate 20 on which the insulating layer is formed. In the layer forming step, the insulating portion 30 including the insulating layer which is further laminated on the second insulating layer 34 provided on the first insulating layer 32 can be formed.

Further, the step of forming the first insulating layer 32 on the core substrate 20 can also be carried out using a general vacuum hot press. For example, it can be carried out by pressing a metal plate such as a heated SUS plate from the side of the organic support. The pressing condition is usually such that the degree of pressure reduction is 1 × 10 ^-2 MPa or less, preferably 1 × 10 ^-3 MPa or less. The heating and pressurization may be carried out in one step. However, from the viewpoint of controlling the bleeding of the resin, it is preferred to carry out the steps of two or more stages and change the respective pressing conditions. For example, in the first stage, the pressing conditions are 70°C to 150°C, the pressure is in the range of 1kgf/cm ² to 15kgf/cm ² , and the pressing condition in the second stage is 150°C to 200°. At °C, the pressure is preferably in the range of 1 kgf/cm ² to 40 kgf/cm ² . The time of each stage is preferably 30 minutes to 120 minutes. The commercially available vacuum presses are exemplified by "MNPC-V-750-5-200" manufactured by Nippon Seiki Co., Ltd., and "VH1-1603" manufactured by Kitagawa Seiki Co., Ltd., and the like.

(Step of forming a through hole)

A through hole 36 is formed in the formed first insulating layer 32. The via hole 36 serves as a path for electrically connecting the first wiring layer 42 and the second wiring layer 44. The through hole 36 is formed by a conventional method such as a drill, a laser, or a plasma, in consideration of the characteristics of the first insulating layer 32. For example, when the protective film is left at this time, the first insulating layer 32 is irradiated with the laser light through the protective film, and the through hole 36 can be formed.

The laser light source that can be used to form the through hole 36 is exemplified by, for example. Carbon dioxide laser, YAG laser, excimer laser, etc. Among them, based on processing speed and cost, it is preferable to use carbon dioxide laser.

The formation of the through holes 36 can be performed using a commercially available laser device. The commercially available carbon dioxide laser device is exemplified by "LC-2E21B/1C" manufactured by HITACHI VIA MECHANICS Co., Ltd., "ML605GTWII" manufactured by Mitsubishi Electric Corporation, and Panasonic splicing system (shared) substrate perforated laser processing. machine.

(roughening step)

Next, a roughening step of roughening the first insulating layer 32 forming the via hole 36 is performed. The order and conditions of the roughening step are not particularly limited, and conventional procedures and conditions which are generally used in the production method of a multilayer printed wiring board can be employed. In the roughening step, the first insulating layer 32 can be roughened by, for example, a swelling treatment by a swelling liquid, a roughening treatment of an oxidizing agent, and a neutralization treatment.

The swelling liquid which can be used in the roughening step is not particularly limited, and examples thereof include an alkali solution, a surfactant solution and the like, and an alkali solution is preferred. The alkali solution of the swelling liquid is preferably a sodium hydroxide solution or a potassium hydroxide solution. Commercially available swelling liquids are, for example, "Swelling Dip Securiganth P" manufactured by ATOTECH Co., Ltd., "Swelling Dip Securiganth SBU", and the like.

The swelling treatment of the swelling liquid is not particularly limited. For example, the core substrate 20 provided with the first insulating layer 32 may be immersed in a swelling liquid at 30 ° C to 90 ° C for 1 minute to 20 minutes. It is preferable to use the first insulating layer from the viewpoint of suppressing the swelling of the resin constituting the first insulating layer 32 to an appropriate degree. 32 is immersed in a swelling solution at 40 ° C ~ 80 ° C for 5 minutes ~ 15 minutes.

The oxidizing agent which can be used in the roughening treatment of the oxidizing agent is not particularly limited, and examples thereof include an alkaline permanganic acid solution obtained by dissolving potassium permanganate or sodium permanganate in an aqueous sodium hydroxide solution. The first insulating layer 32 is preferably immersed in an oxidizing agent solution heated to 60 ° C to 80 ° C for 10 minutes to 30 minutes by roughening treatment with an oxidizing agent such as an alkaline permanganic acid solution. Further, the permanganate concentration in the alkaline permanganic acid solution is preferably from 5% by mass to 10% by mass. The oxidizing agent which is commercially available is, for example, an alkaline permanganic acid solution such as "Concentrate‧Compact P" and "Dosing Solution Securiganth P" manufactured by ATOTECH Co., Ltd., Japan.

The neutralizing liquid which can be used for the neutralization treatment is preferably an acidic aqueous solution, and the commercially available product is, for example, "Reduction Solution Securiganth P" manufactured by ATOTECH Co., Ltd., Japan. The neutralizing treatment by the neutralization liquid can be carried out by immersing the treated surface subjected to the roughening treatment with the oxidizing agent solution in 30 ° C to 80 ° C and in the liquid for 5 minutes to 30 minutes. From the viewpoint of workability and the like, the first insulating layer 32 which has been subjected to the roughening treatment with the oxidizing agent solution is preferably immersed in a liquid at 40 ° C to 70 ° C for 5 minutes to 20 minutes.

The roughening step as described above may also be a so-called desmear step for removing the slag of the through holes 36 formed in the first insulating layer 32.

Further, the through-hole 36 may be subjected to a desmear step in addition to the aforementioned roughening step. Moreover, the desmear step may be a wet desmear step or a dry desmear step.

The specific steps of the desmear step are not particularly limited, and for example, conventional steps and conditions which are generally used when forming an insulating layer of a multilayer printed wiring board can be employed. Examples of the dry type of desmear are exemplified by plasma treatment, and the wet type of desmear is exemplified by, for example, swell treatment of the same swelling solution as the roughening step, treatment of an oxidizing agent, and treatment of a neutralizing liquid. The method.

(Formation of the second wiring layer)

Next, the second wiring layer 44 is formed on the first insulating layer 32 where the roughening step (and the desmear step) is performed.

The second wiring layer 44 can be formed by plating. The second wiring layer 44 can be formed by, for example, a conventionally known technique including an electroless plating step, a mask pattern forming step, an electrolytic plating step, a rapid etching step, a full addition method, or the like, and can be formed to include The wiring layer of the desired wiring pattern. Further, in the step of forming the second interconnect layer 44, the via-hole wiring 36a is collectively formed in the via hole 36.

When the first insulating layer 32 is a build-up insulating layer and the second interconnect layer 44 is a build-up layer of the build-up wiring layer, when the wiring layer of the present embodiment further requires one or more layers, it is necessary to repeat the above-mentioned one or more times. One of the series of steps from the step of forming the first insulating layer 32 to the step of forming the second wiring layer 44 may be described.

(Formation of the second insulating layer)

Next, in the second wiring layer 44 and the formation of the via inner wiring 36a A second insulating layer 34 is formed on the insulating layer 32. The second insulating layer 34 may be formed in the same step by using the same material as the step of forming the first insulating layer 32 including the laminating step, the smoothing step, and the thermal curing step of the bonding film.

By the above steps, the coil-shaped conductive structure 40 having at least a part of the buried insulating portion 30 can be manufactured, and includes a portion including the first wiring layer 42 and a portion of the second wiring layer 44 and the via wiring 36a. The coil-shaped conductive structure 40 and the wiring board 10 of the inductor element which is one of the insulating portions 30 which are extended in the thickness direction of the insulating portion 30 and surrounded by the coil-shaped conductive structure 40.

When the adhesive film of the present invention is used, the magnetic permeability in the range of 1 GHz to 3 GHz can be particularly improved, the magnetic loss can be reduced, and an insulating layer excellent in insulation reliability can be formed, so that it can be provided in an easier step. A wiring board formed of a part of an insulating layer which is not a hollow core structure is used to fabricate a wiring board in which an inductor element for a high-frequency band region of higher performance is extruded.

[Use pattern of wiring board]

As the wiring board of the present embodiment, a wiring board for mounting an electronic component such as a semiconductor wafer can be used. And the wiring board can be used to manufacture various types of semiconductor devices. The semiconductor device including the wiring board can be used for electrical products (for example, computers, mobile phones, digital cameras, televisions, etc.) and vehicles (for example, locomotives, automobiles, electric cars, ships, airplanes, etc.).

[Examples]

Hereinafter, the present invention will be more specifically described based on examples and comparative examples, but the present invention is not limited to the following examples. In addition, the "parts" in the following description means "parts by mass".

<Example 1>

20 parts of liquid bisphenol A type epoxy resin (epoxy equivalent 190, specific gravity 1.2 g/cm ³ , "jER828EL" manufactured by Mitsubishi Chemical Corporation), biphenyl type epoxy resin (epoxy equivalent 291, specific gravity) 1.2g/cm ³ , "NC3000H" manufactured by Nippon Kayaku Co., Ltd., 65 parts, phenoxy resin (weight average molecular weight 38000, specific gravity 1.2g/cm ³ , "YX6954" manufactured by Mitsubishi Chemical Corporation), non-volatile 30 parts by weight of 30% by mass of methyl ethyl ketone (hereinafter referred to as "MEK") and cyclohexanone in a 1:1 solution), while dissolving 30 parts of MEK in 22.5 parts and 22.5 parts of cyclohexanone, the mixture was heated and dissolved. Next, a 60% MEK solution, a phenolic hydroxyl equivalent of 124, and a specific gravity of 1.2, which are nonvolatile components of "LA-7054" (a phenolic hardener containing a triazine skeleton) manufactured by DIC Co., Ltd., are mixed. g/cm ³ ) 40 parts, hardening accelerator ("2E4MZ" manufactured by Shikoku Chemicals Co., Ltd., specific gravity 1.1g/cm ³ ) 0.1 parts, inorganic filler (average particle size 0.5 μm, specific gravity 2.2 g/cm) ³ , an amine-based decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) is used to process 50 parts of SOD-made "SO-C2" cerium oxide), magnetic filler (EPSON ATMIX ( "AW2-08PF3F", Fe-Cr-Si alloy (amorphous), 440 parts of average particle size 3.0 μm, specific gravity 7.0 g/cm ³ ), uniformly dispersed by a high-speed rotary kneading machine to prepare resin paint material. Next, the resin paint was applied to the support of polyethylene terephthalate (hereinafter referred to as "PET" by a die coater so that the thickness of the dried resin composition layer was 50 μm. The film (thickness: 38 μm) was dried for 7 minutes at 75 ° C to 120 ° C (average 100 ° C) so that the amount of residual solvent in the resin composition layer was about 0.4% by mass. Then, a polypropylene film having a thickness of 15 μm was bonded to the surface of the resin composition layer, and rolled into a roll shape to form a roll-shaped film. The sheet-like adhesive film having a side length of 507 mm × 336 mm was obtained by cutting the length of the obtained roll-shaped succeeding film in the longitudinal direction to 507 mm.

<Example 2>

In the first embodiment, an inorganic filler (having an average particle diameter of 0.5 μm and a specific gravity of 2.2 g/cm ³ , an amine decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used to process ADOMTECH. The amount of "SO-C2" is set to 160 parts, and the magnetic filler ("AW2-08PF3F" made by EPSON ATMIX) has an average particle diameter of 3.0 μm and a specific gravity of 7.0 g/cm ³ . The film was obtained in the same manner as in Example 1 except that the amount was changed to 350 parts.

<Example 3>

In the first embodiment, an inorganic filler (having an average particle diameter of 0.5 μm and a specific gravity of 2.2 g/cm ³ , an amine decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used to process ADOMTECH. The amount of "SO-C2" is set to 90 parts, and the magnetic filler ("AW2-08PF3F" made by EPSON ATMIX) has an average particle diameter of 3.0 μm and a specific gravity of 7.0 g/cm ³ . The film was obtained in the same manner as in Example 1 except that the amount was 290 parts.

<Example 4>

In Example 1, except that the inorganic filler (average particle diameter of 0.5 m, specific gravity of 2.2g / cm ^3, to amine Silane coupling agent (Shin-Etsu Chemical (shares) made of "KBM573") process ADOMTECH (shares) manufactured The amount of "SO-C2" is set to 40 parts, and the magnetic filler ("AW2-08PF3F" made by EPSON ATMIX) has an average particle diameter of 3.0 μm and a specific gravity of 7.0 g/cm ³ . The film was obtained in the same manner as in Example 1 except that the amount was changed to 240 parts.

<Example 5>

In the first embodiment, an inorganic filler (having an average particle diameter of 0.5 μm and a specific gravity of 2.2 g/cm ³ , an amine decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used to process ADOMTECH. The amount of "SO-C2" is set to 140 parts, and the magnetic filler ("AW2-08PF3F" made by EPSON ATMIX) has an average particle diameter of 3.0 μm and a specific gravity of 7.0 g/cm ³ . A film was obtained in the same manner as in Example 1 except that the amount was 150 parts.

<Example 6>

In the first embodiment, an inorganic filler (having an average particle diameter of 0.5 μm and a specific gravity of 2.2 g/cm ³ , an amine decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used to process ADOMTECH. The amount of "SO-C2" is set to 80 parts, and the magnetic filler ("AW2-08PF3F" made by EPSON ATMIX) has an average particle diameter of 3.0 μm and a specific gravity of 7.0 g/cm ³ . A film was obtained in the same manner as in Example 1 except that the amount was 130 parts.

<Example 7>

In the first embodiment, an inorganic filler (having an average particle diameter of 0.5 μm and a specific gravity of 2.2 g/cm ³ , an amine decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used to process ADOMTECH. The amount of "SO-C2" is set to 35 parts, and the magnetic filler ("AW2-08PF3F" made by EPSON ATMIX) has an average particle diameter of 3.0 μm and a specific gravity of 7.0 g/cm ³ . The adhesive film was obtained in the same manner as in Example 1 except that the amount was changed to 110 parts.

<Example 8>

So that a liquid bisphenol A epoxy resin (epoxy equivalent 190, specific gravity of 1.2g / cm ^3, manufactured by Mitsubishi Chemical (shares) of the manufactured 'jER828EL ") 14 parts biphenyl type epoxy resin (epoxy equivalent of 291, a specific gravity 1.2 g/cm ³ , "NC3000H" manufactured by Nippon Kayaku Co., Ltd., 14 parts, phenoxy resin (weight average molecular weight 38000, specific gravity 1.2g/cm ³ , "YX6954" manufactured by Mitsubishi Chemical Corporation), non-volatile 40 parts by weight of a 1:1 solution of MEK and cyclohexanone in a component of 30% by mass, and dissolved in 5 parts of MEK and 5 parts of cyclohexanone while stirring. Next, a 60% MEK solution, a phenolic hydroxyl equivalent of 124, and a specific gravity of 1.2, which are nonvolatile components of "LA-7054" (a phenolic hardener containing a triazine skeleton) made by DIC Co., Ltd., are mixed. g/cm ³ ) 30 parts, hardening accelerator ("2E4MZ" manufactured by Shikoku Chemicals Co., Ltd., specific gravity 1.1g/cm ³ ) 0.1 parts, inorganic filler (average particle size 0.5 μm, specific gravity 2.2 g/cm) ³ , an amine-based decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) is used to process 150 parts of "SO-C2" ruthenium dioxide produced by ADOMTECH Co., Ltd., and magnetic filler (EPSON ATMIX ( "AW2-08PF3F", Fe-Cr-Si alloy (amorphous), average particle size 3.0μm, specific gravity 7.0g/cm ³ ) 360 parts, uniformly dispersed by high-speed rotary kneading machine to prepare resin paint A film of the adhesive film was obtained in the same manner as in Example 1.

<Example 9>

In the eighth embodiment, the inorganic filler was set to have an average particle diameter of 1 μm and a specific gravity of 2.2 g/cm ³ , and an amino decane-based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used to process ADOMTECH. A film was obtained in the same manner as in Example 8 except that 150 parts of "SO-C4" was added as the cerium oxide.

<Example 10>

In Example 8, except that the average particle diameter of the inorganic filler is set to 2 m, a specific gravity 2.2g / cm ^3, to amine Silane coupling agent (Shin-Etsu Chemical (shares) made of "KBM573") process ADOMTECH (shares) manufactured A film was obtained in the same manner as in Example 8 except that 150 parts of "SO-C6" was added as the cerium oxide.

<Comparative Example 1>

In Example 1, except that a magnetic filler ("AW2-08PF3F" manufactured by EPSON ATMIX Co., Ltd., an average particle diameter of 3.0 μm, a specific gravity of 7.0 g/cm ³ ) was used, and an inorganic filler (average particle diameter of 0.5 μm, The specific gravity is 2.2 g/cm ³ , and the amount of the "SO-C2" (manufactured by Shin-Etsu Chemical Co., Ltd. "KBM573") is treated with "SO-C2". A film was obtained in the same manner as in Example 1 except for 70 parts.

<Comparative Example 2>

In the first embodiment, the same amount as in the first embodiment except that the amount of the magnetic filler (average particle diameter: 3.0 μm, "AW2-08PF3F" manufactured by EPSON ATMIX Co., Ltd., specific gravity: 7.0 g/cm ³ ) was 700 parts. A follow-up film was obtained.

<Comparative Example 3>

In the first embodiment, the amount of the magnetic filler (average particle diameter: 3.0 μm, "AW2-08PF3F" manufactured by EPSON ATMIX, specific gravity: 7.0 g/cm ³ ) was 210 parts, except that the inorganic filler was not used. The adhesive film was obtained in the same manner as in Example 1.

<Comparative Example 4>

In Example 1, except that the inorganic filler (average particle diameter of 0.5 m, specific gravity of 2.2g / cm ^3, to amine Silane coupling agent (Shin-Etsu Chemical (shares) made of "KBM573") process ADOMTECH (shares) manufactured The amount of "SO-C2" is set to 600 parts, and the magnetic filler (average particle diameter: 3.0 μm, "AW2-08PF3F" manufactured by EPSON ATMIX Co., Ltd., specific gravity: 7.0 g/cm ³ ) The film was obtained in the same manner as in Example 1 except that the amount was 290 parts.

The composition of the resin paint in terms of the nonvolatile content in each of Examples 1 to 7 and Comparative Examples 1 to 4 is shown in Table 1 below. The composition of the resin paint in terms of the nonvolatile content in each of Examples 8 to 10 is shown in Table 2 below.

<Method for Measuring Magnetic Permeability>

In each of Examples 1 to 8 and Comparative Examples 1 to 4, a PET film ("FLUOROJU RL50KSE" manufactured by Mitsubishi Resin Co., Ltd.) treated with a fluororesin-based release agent (ETFE) was used as a support. In the same manner, a film having the same resin composition layer as each of the examples and the comparative examples was obtained. The resin composition layer was thermally hardened by heating the obtained adhesive film at 180 ° C for 90 minutes, and the support was peeled off to obtain a flaky cured product. The obtained cured product was cut into test pieces having a width of 5 mm and a length of 18 mm to prepare an evaluation sample. Using Agilent Technologies "HP8362B" (trade name), the measurement frequency was set to the range of 100 MHz to 10 GHz by a short-circuit strip method, and the magnetic permeability (μ') and magnetic permeability loss of the evaluation sample at room temperature of 23 ° C were measured ( μ"). The magnetic permeability at a measurement frequency of 1 GHz and 3 GHz and the magnetic permeability loss at a measurement frequency of 1 GHz and 3 GHz are shown in Tables 3 and 4 below.

<Evaluation of insulation>

A batch vacuum lamination machine "MVLP-500" (trade name) manufactured by Nippon Seisakusho Co., Ltd. was used, and the respective films obtained in Examples 1 to 8 and Comparative Examples 1 to 4 were laminated to form a film. The wiring pattern of the polyimide film with a thickness of 38 μm and a thickness of 8 μm in the width of the wire and the interval is set to L (line) / S (interval) = 15 μm / 15 μm, and the circuit (wiring pattern) is 8 μm thick. side. The PET film was peeled off from the film formed by the lamination, and heat-hardened at 180 ° C for 90 minutes to form an insulating layer. The obtained laminated structure was used as a sample for evaluation.

First, a voltage of 3.3 V was applied to the obtained sample for evaluation, and the initial resistance value was measured. Further, while applying a voltage of 3.3 V to the sample for evaluation, it was placed in an environment of 130 ° C and a relative humidity of 85% for 100 hours. After standing for 100 hours (after HAST 100 hours), no decrease in the insulation resistance value was observed and the sample was usable. Calculate the test piece usability. When the test piece can be used, the insulation resistance of the insulating layer exceeds 1.0 × 10 ⁶ Ω after being placed for 100 hours, and it is evaluated as "usable". After 100 hours, the insulation resistance of the insulating layer is 1.0 × 10 ⁶ Ω. The evaluation below is "cannot be used". The results are shown in Tables 3 and 4 below. Further, in Comparative Example 4, the adhesive film could not be tested for the useability of the test piece due to a problem in moldability, and the initial resistance value of the test of Comparative Example 4 could not be tested.

<Evaluation of lamination property>

A batch vacuum lamination machine "MVLP-500" (trade name) manufactured by Nihon Seiki Co., Ltd. was used, and the adhesive films obtained in Examples 1 to 8 and Comparative Examples 1 to 4 were laminated on both sides of the wiring board. . The laminating system was pressed at a pressure of 13 hPa or less for 30 seconds, and then pressed at a pressure of 0.74 MPa at 100 ° C for 30 seconds. The evaluation was carried out by examining the appearance of the obtained laminated structure based on the following evaluation criteria. The results are shown in Tables 3 and 4 below.

Evaluation basis

○: The circuit portion of the wiring board has no holes, and the resin composition from the film is sufficiently flowed.

X: Holes were formed in the circuit portion of the wiring board, and the flow of the resin composition derived from the film after lamination was insufficient.

In the examples of the present invention, the resin composition having the above-described composition is excellent in fluidity when the insulating layer is formed, and is excellent in the sealing property of the wiring layer when the insulating layer (cured material) is formed. It is also known that the insulating layer formed using the adhesive film having the resin composition layer containing the resin composition has a magnetic permeability in a high frequency band region (gigahertz band) having a frequency of 1 GHz or more, particularly in the range of 1 GHz to 3 GHz. And inhibit magnetic loss. Further, as a result of the use rate of the test piece, it is understood that the insulating layer formed of the resin composition having the above composition is excellent in insulation reliability. Therefore, if the adhesive film of the present invention is used, a wiring board for squeezing a higher performance high-frequency band inductor element can be provided in a simple step.

20‧‧‧ core substrate (inner circuit board)

20a‧‧‧1st main surface

20b‧‧‧2nd main surface

22‧‧‧through holes

22a‧‧‧Wiring in the through hole

24‧‧‧External terminals

30‧‧‧Insulation

32‧‧‧1st insulation layer

34‧‧‧2nd insulation layer

36‧‧‧through hole

36a‧‧‧Through wiring

40‧‧‧Circular conductive structure

42‧‧‧1st wiring layer

42a‧‧‧ solder pads

44‧‧‧2nd wiring layer

Claims (20)

The adhesive film is a film having a support and a resin composition layer provided on the support, wherein the resin composition layer contains a component (A) a thermosetting resin, a component (B) a magnetic filler, and a component. (C) Inorganic filler, when the nonvolatile content in the resin composition constituting the resin composition layer is 100% by volume, the content of the component (B) is 10% by volume or more, and the content of the component (C) Divided by the content of the component (B), the value is in the range of 0.3 to 3.0. The film according to claim 1, wherein the component (A) is an epoxy resin, and the resin composition further contains an epoxy resin hardener selected from the group consisting of a phenolic curing agent and a naphthol curing agent. The adhesive film according to claim 2, wherein the epoxy resin hardener is selected from the group consisting of a cresy-based hardener containing a triazine skeleton and a phenolic hardener containing a triazine skeleton. The film according to claim 1, wherein the resin composition further contains a thermoplastic resin. The film according to claim 1, wherein the content of the component (B) in the resin composition is from 10% by volume to 40% by volume, and the content of the component (C) is from 10% by volume to 50% by volume. The film according to claim 1, wherein the content of the component (B) and the component (C) in the resin composition is 20% by volume to 75% by volume in total. An adhesive film according to claim 1, wherein the foregoing resin composition The content of the component (B) is from 10% by volume to 25% by volume. The film according to claim 1, wherein the content of the component (B) in the resin composition is 20% by volume to 25% by volume, and the content of the component (C) is 10% by volume to 25% by volume, and the component (B) The total content of the component (C) is from 30% by volume to 50% by volume. The film according to claim 1, wherein the component (B) has an average particle diameter of 0.3 μm to 10 μm in the resin composition. The film according to claim 1, wherein the component (C) has an average particle diameter of from 0.01 μm to 5 μm. The film according to claim 1, wherein the average particle diameter of the component (B) is larger than the average particle diameter of the component (C). An adhesive film according to claim 1, wherein component (C) is cerium oxide. The film according to claim 1, wherein the component (C) is a cerium oxide treated with a surface treating agent. An adhesive film according to claim 13, wherein the surface treating agent is an amino decane-based coupling agent. The film according to claim 1, wherein when the cured product is formed, the magnetic permeability at a frequency of 1 GHz to 3 GHz is 1.1 or more, and the magnetic loss at a frequency of 1 GHz to 3 GHz is 0.5 or less. The film according to claim 1, wherein when the cured product is formed, the magnetic permeability at a frequency of 1 GHz to 3 GHz is 1.2 or more, and the magnetic loss at a frequency of 1 GHz to 3 GHz is 0.3 or less. Such as the film of claim 1, which is used to form an inductor The insulating layer of the wiring board of the device. A wiring board having an insulating layer of a cured material of a resin composition layer of a film according to any one of claims 1 to 16, and a coil-shaped conductive structure in which at least a part of the insulating layer is embedded, and comprising The inductor element is composed of one of the coil-shaped conductive structures and the insulating layer extending in the thickness direction of the insulating layer and surrounded by the coil-shaped conductive structure. The wiring board of claim 18, wherein the frequency at which the inductor element functions is 1 GHz or more. A method of manufacturing a wiring board comprising: an insulating portion including a first insulating layer and a second insulating layer; and a coil-shaped conductive structure in which at least a portion is embedded in the insulating portion, and including the coil-shaped conductive body An inductor element comprising a structural part and a part of the insulating portion, the manufacturing method comprising the steps of: preparing a bonding film according to any one of claims 1 to 16, and a core substrate provided with the first wiring layer a step of laminating the resin composition layer of the adhesive film on the core substrate, thermally curing the resin composition layer to form a first insulating layer, and forming a through hole in the first insulating layer a step of roughening the first insulating layer on which the via hole is formed, forming a second wiring layer on the first insulating layer, and forming the a step of wiring the through hole in the first wiring layer and the second wiring layer, and further bonding the bonding film to the first insulating layer on which the second wiring layer and the via wiring are formed. a step of forming the second insulating layer by thermosetting, and forming a coil-shaped conductive structure including a portion of the first wiring layer and a portion of the second wiring layer and the wiring in the via hole, and insulating the insulating layer a step of extending the thickness direction of the inductor element in a portion of the insulating portion surrounded by the coil-shaped conductive structure.