JP7176556B2 - Resin sheet with support - Google Patents

Description

TECHNICAL FIELD The present invention relates to a support-attached resin sheet. Furthermore, the present invention relates to a printed wiring board manufacturing method, a printed wiring board, and a semiconductor device.

As a method for manufacturing printed wiring boards (hereinafter also referred to as “wiring boards”), a build-up method is widely used in which conductive layers and insulating layers on which circuits are formed are alternately stacked. It is known to be formed by curing a resin composition layer composed of two layers, one on the side that contacts the layer and the other on the side that is plated (see, for example, Patent Document 1).

JP 2014-17301 A

2. Description of the Related Art In recent years, due to an increase in the amount of information communication, finer wiring is desired in the manufacture of printed wiring boards.

In order to achieve fine wiring, the surface of the insulating layer has a low roughness, and of the two resin composition layers, the resin composition layer on the side to be plated (the side in contact with the conductor layer) is filled with inorganic filler. It is desirable to reduce the material content. On the other hand, from the viewpoint of lowering the coefficient of thermal expansion, it is desirable to increase the content of the inorganic filler in the resin composition layer on the other side (the side in contact with the substrate).

The present inventors attempted to form via holes in an insulating layer formed by curing such two resin composition layers. As a result, it was found that a constricted portion was formed in the extending direction of the interfaces of the cured resin composition layers on the sidewall of the via hole (see FIG. 1). If such a gouged portion occurs, a void may be generated during plating, which may hinder fine wiring.

An object of the present invention is to provide a support-attached resin sheet, a method for producing a printed wiring board, a printed wiring board, and a semiconductor device, in which the generation of constricted portions in the extending direction of the interfaces of each cured resin composition layer is suppressed. The task is to provide

As a result of intensive studies on the above problem, the present inventors have found that by reducing the difference in thermal conductivity of the thermosets of the first and second resin composition layers, the interface between the cured resin composition layers can be improved. It was found that the length of the constricted portion generated in the extending direction can be reduced. As a result of further intensive studies by the present inventors, the content of the inorganic filler in the first resin composition layer on the plating side is less than the content of the inorganic filler in the second resin composition layer. By doing so, the difference in thermal conductivity can be reduced, and the present invention has been completed.

That is, the present invention includes the following contents.
[1] A support-attached resin sheet comprising a support and a resin sheet provided on the support,
The resin sheet includes a first resin composition layer formed of a first resin composition and provided on the support side;
a second resin composition layer formed of a second resin composition provided on the side opposite to the support side,
The first resin composition contains (a) an inorganic filler, and the content of component (a) is 30% by mass or less when the non-volatile component in the first resin composition is 100% by mass. ,
The second resin composition contains (a) an inorganic filler, and the content of component (a) is 60% by mass or more when the non-volatile component in the second resin composition is 100% by mass. ,
The thermal conductivity of the first thermoset obtained by thermally curing the first resin composition at 100 ° C. for 30 minutes and further at 190 ° C. for 90 minutes, and the second resin composition at 100 ° C. for 30 minutes, A resin sheet with a support having a thermal conductivity difference of 0.4 W/mK or less from that of a second thermoset obtained by further thermosetting at 190° C. for 90 minutes.
[2] The resin sheet with a support according to [1], wherein the resin sheet has a thickness of 40 μm or less.
[3] The resin sheet with a support according to [1] or [2], wherein the resin sheet has a thickness of 25 μm or less.
[4] When the average particle size of component (a) in the first resin composition is R1 (μm) and the average particle size of component (a) in the second resin composition is R2 (μm), The support-attached resin sheet according to any one of [1] to [3], wherein the ratio of R1 to R2 (R2/R1) is 1-15.
[5] The resin sheet with a support according to any one of [1] to [4], wherein the first resin composition contains (b) an epoxy resin, and the component (b) has a mesogenic skeleton.
[6] Component (b) is at least one selected from bixylenol-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, biphenyl-type epoxy resins, and naphthalene-type epoxy resins. The resin sheet with a support according to .
[7] The support-attached resin sheet according to any one of [1] to [6], which is for forming an insulating layer of a printed wiring board.
[8] (I) Step of laminating the second resin composition layer of the resin sheet with support according to any one of [1] to [7] on the inner layer substrate so as to be bonded to the inner layer substrate (II) ) A method of manufacturing a printed wiring board, comprising the steps of:) thermosetting a resin sheet with a support to form an insulating layer; and (III) forming via holes in the insulating layer and removing the support.
[9] The method for producing a printed wiring board according to [8], wherein in the step (III), via holes are formed in the insulating layer with a laser.
[10] The method for producing a printed wiring board according to [8] or [9], wherein the via hole has an opening diameter of 40 μm or less.
[11] A printed wiring board comprising an insulating layer formed of the support-attached resin sheet according to any one of [1] to [7].
[12] A semiconductor device comprising the printed wiring board according to [11].

According to the present invention, a support-attached resin sheet, a method for producing a printed wiring board, a printed wiring board, and a semiconductor device are provided in which the generation of constricted portions in the extending direction of the interfaces of each cured resin composition layer is suppressed. have been able to provide.

FIG. 1 is a cross-sectional photograph of an insulating layer having a gouged portion. FIG. 2 is a schematic diagram showing one embodiment of the support-attached resin sheet of the present invention. FIG. 3 is a cross-sectional photograph for explaining the length of the gouged portion.

Hereinafter, the resin sheet with a support, the method for producing a printed wiring board, the printed wiring board, and the semiconductor device of the present invention will be described in detail.

Before describing the resin sheet with support of the present invention in detail, in the resin sheet with support of the present invention, when forming the first resin composition layer and the second resin composition layer contained in the resin sheet, The first resin composition and the second resin composition used for the above will be described.

(First resin composition)
The first resin composition forming the first resin composition layer contains (a) an inorganic filler, and the content of the component (a) is 100% by mass of the non-volatile components in the first resin composition. , it is not particularly limited as long as it is 30% by mass or less, and the cured product may have sufficient plating peelability and insulating properties. Examples of the first resin composition include a composition containing a curable resin and its curing agent in addition to an inorganic filler. As the curable resin, conventionally known curable resins used for forming insulating layers of printed wiring boards can be used, and among them, epoxy resins are preferable. Accordingly, in one embodiment, the first resin composition comprises (b) an epoxy resin and (c) a curing agent. The first resin composition may further contain a thermoplastic resin, a curing accelerator, a flame retardant and an organic filler, if necessary.

Each component that can be used as the material of the first resin composition will be described in detail below.

-(a) Inorganic filler-
The material of the inorganic filler is not particularly limited, but examples include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, and water. Aluminum oxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide , zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, zirconium phosphate tungstate, silicon carbide, and the like. Among these, silicon carbide and silica are preferred, and silica is particularly preferred. As silica, spherical silica is preferable. An inorganic filler may be used individually by 1 type, and may be used in combination of 2 or more type.

Although the average particle size of the inorganic filler is not particularly limited, it is preferably 2 μm or less, more preferably 1.5 μm or less, and still more preferably 1 μm from the viewpoint of obtaining an insulating layer with a small surface roughness and improving the fine wiring formability. It is below. Although the lower limit of the average particle diameter is not particularly limited, it is preferably 0.01 μm or more, more preferably 0.1 μm or more, and still more preferably 0.3 μm or more. Examples of commercially available inorganic fillers having such an average particle size include "UFP-30" manufactured by Denki Kagaku Kogyo Co., Ltd., "SPH516-05" manufactured by Nippon Steel & Sumikin Materials Co., Ltd., and Shinano Electric Refining. Co., Ltd. "SER-A06" and the like.

The average particle size of the inorganic filler can be measured by a laser diffraction/scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler is prepared on a volume basis using a laser diffraction/scattering particle size distribution analyzer, and the median diameter thereof can be used as the average particle size for measurement. As a measurement sample, one obtained by dispersing an inorganic filler in methyl ethyl ketone by ultrasonic waves can be preferably used. As a laser diffraction scattering type particle size distribution analyzer, "SALD-2200" manufactured by Shimadzu Corporation can be used.

The inorganic filler is preferably surface-treated with at least one surface treatment agent selected from silane coupling agents, alkoxysilane compounds, and organosilazane compounds from the viewpoint of enhancing moisture resistance and dispersibility. These may be oligomers. Examples of surface treatment agents include aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, organosilazane compounds, and titanate coupling agents. Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. silane), Shin-Etsu Chemical Co., Ltd. "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd. "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "SZ-31" (hexamethyldisilazane), Shin-Etsu Chemical Co., Ltd. "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "KBM-4803" (long chain epoxy type silane coupling agents) and the like. One type of surface treatment agent may be used alone, or two or more types may be used in combination.

The degree of surface treatment by the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. 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, and more preferably 0.2 mg/m ² from the viewpoint of improving the dispersibility of the inorganic filler. The above is more preferable. On the other hand, from the viewpoint of suppressing the melt viscosity of the resin varnish and the melt viscosity in the sheet form, it is preferably 1 mg/m ² or less, more preferably 0.8 mg/m ² or less, and further preferably 0.5 mg/m ² or less. preferable.

The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (eg, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler surface-treated with the surface treatment agent, and ultrasonic cleaning is performed at 25° C. for 5 minutes. After removing the supernatant liquid and drying the solid content, a carbon analyzer can be used to measure the amount of carbon per unit surface area of the inorganic filler. As a carbon analyzer, "EMIA-320V" manufactured by Horiba Ltd. can be used.

The content of the inorganic filler in the first resin composition is 30% by mass or less when the non-volatile component in the first resin composition is 100% by mass from the viewpoint of improving the peelability of plating, It is preferably 25% by mass or less, more preferably 20% by mass or less. The lower limit of the content of component (c) in the first resin composition is not particularly limited.

-(b) epoxy resin-
Examples of epoxy resins include bixylenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, Naphthol novolak type epoxy resin, phenol novolak type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin having a butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring-containing epoxy resin, cyclohexanedimethanol type epoxy resin, naphthylene Ether-type epoxy resins, trimethylol-type epoxy resins, tetraphenylethane-type epoxy resins, and the like are included. An epoxy resin may be used individually by 1 type, and may be used in combination of 2 or more types. In terms of increasing thermal conductivity, the component (b) is preferably an epoxy resin having a mesogenic skeleton, such as bixylenol epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, biphenyl epoxy resin, and naphthalene type epoxy resin. The mesogenic skeleton is a generic term for groups that are rod-like or plate-like and include rigid groups (aromatic rings) that exhibit liquid crystallinity.

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 mass %, at least 50 mass % or more of the epoxy resin preferably has two or more epoxy groups in one molecule. Among them, an epoxy resin that has two or more epoxy groups in one molecule and is liquid at a temperature of 20 ° C. (hereinafter referred to as "liquid epoxy resin"), and three or more epoxy groups in one molecule, It preferably contains an epoxy resin that is solid at a temperature of 20° C. (hereinafter referred to as “solid epoxy resin”). By using both a liquid epoxy resin and a solid epoxy resin as epoxy resins, a resin composition having excellent flexibility can be obtained. Moreover, the breaking strength of the cured product of the resin composition is also improved.

Examples of liquid epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, phenol novolak type epoxy resin, ester skeleton. An alicyclic epoxy resin having a type epoxy resins and naphthalene type epoxy resins are more preferred. Specific examples of liquid epoxy resins include "HP4032", "HP4032D" and "HP4032SS" (naphthalene type epoxy resins) manufactured by DIC Corporation, "828US", "jER828EL" and "825" manufactured by Mitsubishi Chemical Corporation. " (bisphenol A type epoxy resin), "jER807", "1750" (bisphenol F type epoxy resin), "jER152" (phenol novolac type epoxy resin), "630", "630LSD" (glycidylamine type epoxy resin), Nippon Steel & Sumikin Chemical Co., Ltd. "ZX1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin), Nagase ChemteX Corporation "EX-721" (glycidyl ester type epoxy resin), ( Daicel Co., Ltd. "Celoxide 2021P" (alicyclic epoxy resin having an ester skeleton), "PB-3600" (epoxy resin having a butadiene structure), Nippon Steel Chemical Co., Ltd. "ZX1658", "ZX1658GS" (liquid 1,4-glycidylcyclohexane), Mitsubishi Chemical Corporation "630LSD" (glycidylamine type epoxy resin), and the like. These may be used individually by 1 type, and may be used in combination of 2 or more type.

Solid epoxy resins include naphthalene type tetrafunctional epoxy resin, cresol novolak type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, Anthracene type epoxy resin, bisphenol A type epoxy resin and tetraphenylethane type epoxy resin are preferred, and naphthalene type tetrafunctional epoxy resin, naphthol type epoxy resin and biphenyl type epoxy resin are more preferred. Specific examples of solid epoxy resins include "HP4032H" (naphthalene-type epoxy resin), "HP-4700", "HP-4710" (naphthalene-type tetrafunctional epoxy resin), and "N-690" manufactured by DIC Corporation. ” (cresol novolac type epoxy resin), “N-695” (cresol novolak type epoxy resin), “HP-7200” (dicyclopentadiene type epoxy resin), “HP-7200HH”, “HP-7200H”, “EXA -7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (naphthylene ether type epoxy resin), "EPPN" manufactured by Nippon Kayaku Co., Ltd. -502H” (trisphenol type epoxy resin), “NC7000L” (naphthol novolac type epoxy resin), “NC3000H”, “NC3000”, “NC3000L”, “NC3100” (biphenyl type epoxy resin), Nippon Steel & Sumikin Chemical Co., Ltd. "ESN475V" (naphthalene type epoxy resin), "ESN485" (naphthol novolak type epoxy resin) manufactured by Mitsubishi Chemical Corporation, "YX4000H", "YL6121" (biphenyl type epoxy resin), "YX4000HK" (bixylenol type epoxy resin), "YX8800" (anthracene type epoxy resin), "PG-100" and "CG-500" manufactured by Osaka Gas Chemicals Co., Ltd., "YL7760" manufactured by Mitsubishi Chemical Corporation (Bisphenol AF type epoxy resin), "YL7800" (fluorene type epoxy resin), "jER1010" (solid bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Corporation, "jER1031S" (tetraphenylethane type epoxy resin), and the like. These may be used individually by 1 type, and may be used in combination of 2 or more type.

When a liquid epoxy resin and a solid epoxy resin are used together as the epoxy resin, the ratio by mass (liquid epoxy resin: solid epoxy resin) is in the range of 0:0.1 to 1:15. preferable. By setting the amount ratio of the liquid epoxy resin to the solid epoxy resin in such a range, i) when used in the form of a resin sheet, moderate adhesiveness is provided, and ii) when used in the form of a resin sheet. iii) a cured product having sufficient breaking strength can be obtained. From the viewpoint of the above effects i) to iii), the ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) is in the range of 0:0.3 to 1:10 by mass. is more preferred, and a range of 0:0.6 to 1:8 is even more preferred.

From the viewpoint of obtaining an insulating layer exhibiting good mechanical strength and insulation reliability, the content of the epoxy resin in the first resin composition is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably It is 3 mass % or more. The upper limit of the epoxy resin content is not particularly limited as long as the effect of the present invention is exhibited, but is preferably 80% by mass or less, more preferably 70% by mass or less, and still more preferably 60% by mass or less.

In the present invention, the content of each component in the resin composition is a value when the non-volatile component in the resin composition is 100% by mass, unless otherwise specified.

The epoxy equivalent of the epoxy resin is preferably 50-5000, more preferably 50-3000, even more preferably 80-2000, still more preferably 110-1000. Within this range, the crosslink density of the cured product is sufficient, and an insulating layer with a small surface roughness can be obtained. The epoxy equivalent can be measured according to JIS K7236, and is the mass of a resin containing one equivalent of epoxy groups.

The weight average molecular weight of the epoxy resin is preferably 100-5000, more preferably 250-3000, still more preferably 400-1500. Here, the weight average molecular weight of the epoxy resin is the polystyrene equivalent weight average molecular weight measured by gel permeation chromatography (GPC).

-(c) curing agent-
The curing agent is not particularly limited as long as it has the function of curing the epoxy resin. Examples include carbodiimide curing agents. A single curing agent may be used alone, or two or more curing agents may be used in combination. Component (c) is preferably one or more selected from phenol-based curing agents, naphthol-based curing agents, active ester-based curing agents, carbodiimide-based curing agents, and cyanate ester-based curing agents.

As the phenolic curing agent and the naphtholic curing agent, a phenolic curing agent having a novolac structure or a naphtholic curing agent having a novolac structure is preferable from the viewpoint of heat resistance and water resistance. From the viewpoint of adhesion to the conductor layer, a nitrogen-containing phenolic curing agent is preferable, and a triazine skeleton-containing phenolic curing agent is more preferable. Among them, a triazine skeleton-containing phenol novolac curing agent is preferable from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion to the conductor layer.

Specific examples of phenol-based curing agents and naphthol-based curing agents include, for example, “MEH-7700”, “MEH-7810”, “MEH-7851”, “MEH-7851H” manufactured by Meiwa Kasei Co., Ltd., Nippon Kasei Co., Ltd. "NHN", "CBN", "GPH" manufactured by Yaku Co., Ltd., "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN495" manufactured by Nippon Steel & Sumikin Co., Ltd. SN375”, “SN395”, DIC Corporation “TD-2090”, “LA-7052”, “LA-7054”, “LA-1356”, “LA-3018-50P”, “EXB-9500” etc.

From the viewpoint of obtaining an insulating layer having excellent adhesion to the conductor layer, an active ester curing agent is also preferred. The active ester curing agent is not particularly limited, but in general, one molecule of an ester group with high reaction activity such as phenol esters, thiophenol esters, N-hydroxyamine esters, esters of heterocyclic hydroxy compounds, etc. A compound having two or more in it is preferably used. The active ester curing agent is preferably obtained by a condensation reaction between a carboxylic acid compound and/or a thiocarboxylic acid compound and a hydroxy compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferred, and an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methylated 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, phloroglucine, Benzenetriol, dicyclopentadiene-type diphenol compound, phenol novolak, and the like. Here, the term "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing one molecule of dicyclopentadiene with two molecules of phenol.

Specifically, an active ester compound containing a dicyclopentadiene type diphenol structure, an active ester compound containing a naphthalene structure, an active ester compound containing an acetylated product of phenol novolac, and an active ester compound containing a benzoylated product of phenol novolak are preferred. Among them, an active ester compound containing a naphthalene structure and an active ester compound containing a dicyclopentadiene-type diphenol structure are more preferable. "Dicyclopentadiene-type diphenol structure" represents a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

Commercially available active ester curing agents include, as active ester compounds containing a dicyclopentadiene type diphenol structure, "EXB9451", "EXB9460", "EXB9460S", "HPC-8000-65T", and "HPC-8000H- 65TM", "EXB-8000L-65TM" (manufactured by DIC Corporation), "EXB9416-70BK" (manufactured by DIC Corporation) as an active ester compound containing a naphthalene structure, as an active ester compound containing an acetylated phenol novolac "DC808" (manufactured by Mitsubishi Chemical Corporation), "YLH1026" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing a benzoylated phenol novolac, and "DC808" as an active ester curing agent that is an acetylated phenol novolak. ” (Mitsubishi Chemical Co., Ltd.), and “YLH1026” (Mitsubishi Chemical Co., Ltd.), “YLH1030” (Mitsubishi Chemical Co., Ltd.), and “YLH1048” as active ester curing agents that are benzoyl compounds of phenol novolak. (manufactured by Mitsubishi Chemical Corporation) and the like.

Specific examples of benzoxazine-based curing agents include "HFB2006M" manufactured by Showa High Polymer Co., Ltd., and "Pd" and "Fa" manufactured by Shikoku Kasei Kogyo Co., Ltd.

Examples of cyanate ester curing agents include bisphenol A dicyanate, polyphenolcyanate, oligo(3-methylene-1,5-phenylenecyanate), 4,4′-methylenebis(2,6-dimethylphenylcyanate), 4,4 '-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatophenylmethane), bis(4-cyanate-3,5-dimethyl Bifunctional cyanate resins such as phenyl)methane, 1,3-bis(4-cyanatophenyl-1-(methylethylidene))benzene, bis(4-cyanatophenyl)thioether, and bis(4-cyanatophenyl)ether, phenol Polyfunctional cyanate resins derived from novolacs, cresol novolaks, etc., and prepolymers obtained by partially triazine-forming these cyanate resins. Specific examples of cyanate ester curing agents include "PT30" and "PT60" (both phenol novolac type polyfunctional cyanate ester resins), "BA230" and "BA230S75" (bisphenol A dicyanate) manufactured by Lonza Japan Co., Ltd. a prepolymer that is partially or wholly triazined to form a trimer), and the like.

Specific examples of carbodiimide-based curing agents include “V-03” and “V-07” manufactured by Nisshinbo Chemical Co., Ltd., and the like.

The ratio of the epoxy resin to the curing agent is [total number of epoxy groups in the epoxy resin]:[total number of reactive groups in the curing agent], and is preferably in the range of 1:0.01 to 1:2. 1:0.015 to 1:1.5 is more preferred, and 1:0.02 to 1:1 is even more preferred. Here, the reactive group of the curing agent is an active hydroxyl group, an active ester group, or the like, and varies depending on the type of curing agent. Further, the total number of epoxy groups in the epoxy resin is the sum of the values obtained by dividing the solid mass of each epoxy resin by the epoxy equivalent for all epoxy resins, and the total number of reactive groups in the curing agent is It is a value obtained by dividing the solid content mass of each curing agent by the reactive group equivalent and totaling all the curing agents. By setting the ratio between the epoxy resin and the curing agent within this range, the heat resistance of the cured product of the resin composition is further improved.

In one embodiment, the first resin composition comprises (b) an epoxy resin and (c) a curing agent as described above. In the resin composition, (b) an epoxy resin is a mixture of a liquid epoxy resin and a solid epoxy resin (the mass ratio of liquid epoxy resin:solid epoxy resin is preferably 0:0.1 to 1:15, more preferably 0:0.3 to 1:12, more preferably 0:0.6 to 1:10), and (c) a phenolic curing agent, naphthol curing agent, active ester curing agent, carbodiimide curing agent and cyanate ester-based curing agents.

The content of the curing agent in the first resin composition is not particularly limited, but is preferably 45% by mass or less, more preferably 43% by mass or less, and even more preferably 40% by mass or less. The lower limit is not particularly limited, but is preferably 10% by mass or more, more preferably 15% by mass or more.

-(d) thermoplastic resin-
The first resin composition may contain (d) a thermoplastic resin in addition to the components (a) to (c).

Examples of thermoplastic resins include phenoxy resins, polyvinyl acetal resins, polyolefin resins, polybutadiene resins, polyimide resins, polyamideimide resins, polyetherimide resins, polysulfone resins, polyethersulfone resins, polyphenylene ether resins, polycarbonate resins, polyether resins. Examples include ether ketone resins and polyester resins, and phenoxy resins are preferred. The thermoplastic resin may be used singly or in combination of two or more.

The polystyrene equivalent weight average molecular weight of the thermoplastic resin is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and even 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 weight average molecular weight of the thermoplastic resin in terms of polystyrene is measured by LC-9A/RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P/K- manufactured by Showa Denko Co., Ltd. as a column. 804L/K-804L can be calculated by using chloroform or the like as a mobile phase, measuring the column temperature at 40° C., and using a standard polystyrene calibration curve.

Examples of phenoxy resins include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, and terpene. and a phenoxy resin having one or more skeletons selected from the group consisting of a trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. A phenoxy resin may be used individually by 1 type, and may be used in combination of 2 or more type. Specific examples of phenoxy resins include "1256" and "4250" manufactured by Mitsubishi Chemical Corporation (both phenoxy resins containing bisphenol A skeleton), "YX8100" (phenoxy resin containing bisphenol S skeleton), and "YX6954" ( bisphenolacetophenone skeleton-containing phenoxy resins), and in addition, "FX280" and "FX293" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.; "YL7769BH30", "YL6794", "YL7213", "YL7290", "YL7891BH30" and "YL7482".

Examples of polyvinyl acetal resins include polyvinyl formal resins and polyvinyl butyral resins, and polyvinyl butyral resins are preferred. Specific examples of polyvinyl acetal resins include Denka Butyral 4000-2, Denka Butyral 5000-A, Denka Butyral 6000-C, and Denka Butyral 6000-EP manufactured by Denka Kogyo Co., Ltd. , S-lec BH series manufactured by Sekisui Chemical Co., Ltd., BX series (eg BX-5Z), KS series (eg KS-1), BL series, BM series and the like.

Specific examples of the polyimide resin include "Ricacoat SN20" and "Ricacoat PN20" manufactured by Shin Nippon Rika Co., Ltd. Specific examples of polyimide resins also include linear polyimides obtained by reacting bifunctional hydroxyl group-terminated polybutadiene, diisocyanate compounds and tetrabasic acid anhydrides (polyimides described in JP-A-2006-37083), and polysiloxane skeletons. Examples include modified polyimides such as polyimide containing (polyimides described in JP-A-2002-12667 and JP-A-2000-319386).

Specific examples of polyamide-imide resins include "VYLOMAX HR11NN" and "VYLOMAX HR16NN" manufactured by Toyobo Co., Ltd. Specific examples of polyamideimide resins include modified polyamideimides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamideimides) manufactured by Hitachi Chemical Co., Ltd.

Specific examples of the polyethersulfone resin include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd., and the like.

Specific examples of the polysulfone resin include polysulfone "P1700" and "P3500" manufactured by Solvay Advanced Polymers.

Specific examples of the polyphenylene ether resin include oligophenylene ether/styrene resin "OPE-2St1200" manufactured by Mitsubishi Gas Chemical Co., Ltd., and the like.

Among them, phenoxy resin and polyvinyl acetal resin are preferable as the thermoplastic resin. Accordingly, in one preferred embodiment, the thermoplastic resin comprises one or more selected from the group consisting of phenoxy resins and polyvinyl acetal resins.

When the first resin composition contains a thermoplastic resin, the content of the thermoplastic resin is preferably 0.5% by mass to 15% by mass, more preferably 0.6% by mass to 12% by mass, and still more preferably is 0.7% by mass to 10% by mass.

-(e) curing accelerator-
The first resin composition may contain (e) a curing accelerator in addition to the components (a) to (c).

Examples of curing accelerators include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, and metal-based curing accelerators. Curing accelerators, imidazole-based curing accelerators, and metallic curing accelerators are preferred, and amine-based curing accelerators, imidazole-based curing accelerators, and metallic curing accelerators are more preferred. A hardening accelerator may be used individually by 1 type, and may be used in combination of 2 or more type.

Phosphorus curing accelerators include, for example, triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate. , tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate, and triphenylphosphine and tetrabutylphosphonium decanoate are preferred.

Examples of amine curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo (5,4,0)-undecene and the like, with 4-dimethylaminopyridine and 1,8-diazabicyclo(5,4,0)-undecene being preferred.

Examples of imidazole curing accelerators include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl- 2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecyl imidazolyl-(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 isocyanurate, 2-phenylimidazole isocyanurate, 2-phenyl-4,5-dihydroxymethylimidazole, 2- Phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline , 2-phenylimidazoline and the like, and adducts of imidazole compounds and epoxy resins, with 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole being preferred.

As the imidazole-based curing accelerator, a commercially available product may be used, such as "P200-H50" manufactured by Mitsubishi Chemical Corporation.

Guanidine curing accelerators include, for example, dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, Tetramethylguanidine, Pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0] Dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1 -allylbiguanide, 1-phenylbiguanide, 1-(o-tolyl)biguanide and the like, with dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene being preferred.

Metal-based curing accelerators include, for example, organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organocobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organocopper complexes such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. organic zinc complexes such as iron (III) acetylacetonate; organic nickel complexes such as nickel (II) acetylacetonate; organic manganese complexes such as manganese (II) acetylacetonate; Examples of organic metal salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

The content of the curing accelerator in the first resin composition is not particularly limited, but is preferably 0.01% by mass to 3% by mass when the non-volatile components of the epoxy resin and curing agent are taken as 100% by mass.

-(f) flame retardant-
The first resin composition may contain (f) a flame retardant. Examples of flame retardants include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, and metal hydroxides. A flame retardant may be used individually by 1 type, or may use 2 or more types together.

As the flame retardant, a commercially available product may be used, and examples thereof include “HCA-HQ” manufactured by Sanko Co., Ltd. and “PX-200” manufactured by Daihachi Chemical Industry Co., Ltd.

When the first resin composition contains a flame retardant, the content of the flame retardant is not particularly limited, but is preferably 0.5% by mass to 20% by mass, more preferably 0.5% by mass to 15% by mass, More preferably 0.5% by mass to 10% by mass.

-(g) organic filler-
From the viewpoint of improving elongation, the resin composition may contain (g) an organic filler. Any organic filler that can be used in forming the insulating layer of a printed wiring board may be used as the organic filler, and examples thereof include rubber particles, polyamide fine particles, silicone particles, and the like.

As the rubber particles, commercially available products may be used, such as "EXL2655" manufactured by Dow Chemical Japan Co., Ltd., "AC3816N" manufactured by Ganz Kasei Co., Ltd., and the like.

When the first resin composition contains an organic filler, the content of the organic filler is preferably 0.1% by mass to 20% by mass, more preferably 0.2% by mass to 10% by mass, and still more preferably is 0.3% to 5% by weight, or 0.5% to 3% by weight.

-(h) optional additives-
The first resin composition may further contain other additives as necessary, and examples of such other additives include organic copper compounds, organic zinc compounds, organic cobalt compounds, and the like. Resin additives such as metal compounds, thickeners, antifoaming agents, leveling agents, adhesion-imparting agents, and coloring agents are included.

(Second resin composition)
The second resin composition forming the second resin composition layer contains (a) an inorganic filler, and the content of the component (a) is 100% by mass of the non-volatile components in the second resin composition. , it is not particularly limited as long as it is 60% by mass or more, that is, if the composition is different from the first resin composition, but the second resin composition contains an inorganic filler, an epoxy resin, and a curing agent. preferably containing.

Examples of the inorganic filler in the second resin composition include those similar to the inorganic filler described in the section (First resin composition).

Although the average particle diameter of the inorganic filler in the second resin composition is not particularly limited, it is preferably 2.5 μm or less, more preferably 2.0 μm or less, and still more preferably 1 μm or less from the viewpoint of via sidewall shape uniformity. .5 μm or less. Although the lower limit of the average particle diameter is not particularly limited, it is preferably 0.8 μm or more, more preferably 0.9 μm or more, and still more preferably 1.0 μm or more. Examples of commercially available inorganic fillers having such an average particle size include "SP60-05" and "SP507-05" manufactured by Nippon Steel & Sumikin Materials Co., Ltd., "YC100C" manufactured by Admatechs Co., Ltd., " YA050C", "YA050C-MJE", "YA010C", "UFP-30" manufactured by Denki Kagaku Kogyo Co., Ltd., "Silfil NSS-3N" manufactured by Tokuyama Co., Ltd. "Silfil NSS-4N", "Silfil NSS-5N" ”, “SC2500SQ”, “SO-C4”, “SO-C2”, “SO-C1” manufactured by Admatechs Co., Ltd., and the like.

When the average particle size of the inorganic filler in the first resin composition is R1 (μm) and the average particle size of the inorganic filler in the second resin composition is R2 (μm), the relationship of R1≦R2 is preferably satisfied. Also, the ratio of R1 to R2 (R2/R1) is preferably 1 or more, more preferably 1.1 or more, still more preferably 1.5 or more, or 2 or more. Although the upper limit of R2/R1 is not particularly limited, it is preferably 15 or less, more preferably 10 or less, and even more preferably 8 or less. For example, when a plurality of inorganic fillers are contained in the first resin composition, the average value of the average particle diameters of the plurality of inorganic fillers is defined as R1 (the same applies to the second resin composition. ).

As the second resin composition, from the viewpoint of suppressing warpage, the content of the inorganic filler is 60% by mass or more when the non-volatile component in the second resin composition is 100% by mass. % or more, more preferably 67 mass % or more. The upper limit of the content of the inorganic filler in the second resin composition is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 80% by mass or less.

When the content of the inorganic filler in the first resin composition is A1 (% by mass) and the content of the inorganic filler in the second resin composition is A2 (% by mass), the relationship of A1<A2 is preferably satisfied. Also, the difference between A1 and A2 (A2-A1) is preferably 30% by mass or more, more preferably 40% by mass or more, and still more preferably 50% by mass or more. Although the upper limit of the difference (A2-A1) is not particularly limited, it can usually be 90% by mass or less, 80% by mass or less, or the like.

In one embodiment, the second resin composition includes an epoxy resin and a curing agent along with an inorganic filler. The second resin composition may further contain additives such as thermoplastic resins, curing accelerators, flame retardants and organic fillers, if necessary.

The epoxy resin, curing agent, and additives contained in the second resin composition are the same as (b) the epoxy resin, (c) curing agent, and additives described in the <First resin composition> section. is mentioned.

The content of the epoxy resin in the second resin composition is preferably 0.1% by mass or more, more preferably 5% by mass or more, from the viewpoint of obtaining an insulating layer exhibiting good mechanical strength and insulation reliability. Preferably, it is 10% by mass or more. The upper limit of the epoxy resin content is not particularly limited as long as the effects of the present invention are exhibited, but is preferably 30% by mass or less, more preferably 25% by mass or less, and still more preferably 22% by mass or less. Therefore, the content of (b) the epoxy resin in the second resin composition is preferably 0.1 to 30% by mass, more preferably 5 to 25% by mass, still more preferably 8 to 22% by mass.

When the content of the epoxy resin in the first resin composition is B1 (% by mass) and the content of the epoxy resin in the second resin composition is B2 (% by mass), the relationship B1>B2 is satisfied. is preferred. Also, the difference (B1-B2) between B1 and B2 is preferably 5% by mass or more, more preferably 8% by mass or more, and still more preferably 10% by mass or more. Although the upper limit of the difference (B1-B2) is not particularly limited, it can usually be 60% by mass or less, 50% by mass or less, or the like.

When a liquid epoxy resin and a solid epoxy resin are used together as the epoxy resin, the ratio by mass (liquid epoxy resin: solid epoxy resin) is in the range of 0:0.1 to 1:15. preferable. By setting the amount ratio of the liquid epoxy resin to the solid epoxy resin in such a range, i) when used in the form of a resin sheet, moderate adhesiveness is provided, and ii) when used in the form of a resin sheet. iii) a cured product having sufficient breaking strength can be obtained. From the viewpoint of the above effects i) to iii), the ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) is in the range of 0:0.3 to 1:10 by mass. is more preferred, and a range of 0:0.6 to 1:8 is even more preferred.

The suitable range of the epoxy equivalent weight of the epoxy resin and the weight average molecular weight of the epoxy resin in the second resin composition are the same as those of the epoxy resin contained in the first resin composition.

The content of the curing agent in the second resin composition is not particularly limited, but from the viewpoint of obtaining an insulating layer with a low dielectric loss tangent, it is preferably 0.1% by mass or more, more preferably 1% by mass or more, and still more preferably It is 5% by mass or more. The upper limit of the content of the curing agent is not particularly limited as long as the effects of the present invention are exhibited, but is preferably 20% by mass or less, more preferably 15% by mass or less, and still more preferably 12% by mass or less. Therefore, the content of the curing agent in the second resin composition is preferably 0.1 to 20 mass %, more preferably 1 to 15 mass %, still more preferably 5 to 12 mass %.

The ratio of the epoxy resin to the curing agent in the second resin composition is [total number of epoxy groups in the epoxy resin]:[total number of reactive groups in the curing agent], which is 1:0.2. ~1:2 is preferred, 1:0.3 to 1:1.5 is more preferred, and 1:0.4 to 1:1 is even more preferred. By setting the ratio between the epoxy resin and the curing agent within this range, the heat resistance of the cured product of the second resin composition is further improved.

The content of the thermoplastic resin in the second resin composition is not particularly limited, but is preferably 0% by mass to 10% by mass, more preferably 0.2% by mass to 8% by mass, and still more preferably 0.5% by mass. % to 5% by mass.

Although the content of the curing accelerator in the second resin composition is not particularly limited, it is preferably used in the range of 0.001% by mass to 3% by mass.

The content of the flame retardant in the second resin composition is not particularly limited, but is preferably 0.2% by mass to 20% by mass, more preferably 0.5% by mass to 15% by mass, and still more preferably 0.8% by mass. % to 10% by mass is more preferred.

The content of the organic filler in the second resin composition is preferably 0.1% by mass to 20% by mass, more preferably 0.2% by mass to 10% by mass.

In the same manner as the first resin composition, the second resin composition contains optional additives such as organometallic compounds such as organocopper compounds, organozinc compounds and organocobalt compounds, and organic fillers, if necessary. Resin additives such as thickeners, antifoaming agents, leveling agents, adhesion imparting agents, and coloring agents may also be included.

[Resin sheet with support]
A support-attached resin sheet of the present invention is a support-attached resin sheet comprising a support and a resin sheet provided on the support, wherein the resin sheet is provided on the support side and provided on the first Having a first resin composition layer formed of a resin composition and a second resin composition layer formed of a second resin composition provided on the side opposite to the support, The first resin composition contains (a) an inorganic filler, and the content of component (a) is 30% by mass or less when the non-volatile component in the first resin composition is 100% by mass. , the second resin composition contains (a) an inorganic filler, and the content of component (a) is 60% by mass or more when the non-volatile component in the second resin composition is 100% by mass. The thermal conductivity of the first thermoset obtained by thermally curing the first resin composition at 100 ° C. for 30 minutes and further at 190 ° C. for 90 minutes, and the thermal conductivity of the second resin composition at 100 ° C. for 30 minutes The difference from the thermal conductivity of the second thermoset obtained by heat curing at 190° C. for 90 minutes is 0.4 W/mK or less.

An example of the support-attached resin sheet of the present invention is shown in FIG. In FIG. 2 , the support-attached resin sheet 10 includes a support 11 and a resin sheet 12 provided on the support 11 . In FIG. 2, the resin sheet 12 comprises a first resin composition layer 13 provided on the side of the support and a second resin composition layer 14 provided on the side opposite to the support.

The support and the resin sheet of the resin sheet with support of the present invention are described in detail below.

<Support>
Examples of the support include a film made of a plastic material, a metal foil, and a release paper, and a film made of a plastic material and a metal foil are preferable.

When a film made of a plastic material is used as the support, examples of the plastic material include polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN"). ), polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylic such as polymethyl methacrylate (PMMA), cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketones, polyimides, and the like. Among them, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is particularly preferable.

When a metal foil is used as the support, examples of the metal foil include copper foil and aluminum foil, with copper foil being preferred. As the copper foil, a foil made of a single metal of copper may be used, and a foil made of an alloy of copper and other metals (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used. may be used.

The support may be subjected to matte treatment or corona treatment on the surface to be bonded to the first resin composition layer.

As the support, a support with a release layer having a release layer on the surface to be bonded to the first resin composition layer may be used. The release agent used in the release layer of the release layer-attached support includes, for example, one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. . As the support with a release layer, a commercially available product may be used, for example, "SK-1" manufactured by Lintec Corporation, which is a PET film having a release layer containing an alkyd resin release agent as a main component. , “AL-5”, “AL-7” and the like.

The thickness of the 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. When a release layer-attached support is used, the thickness of the release layer-attached support as a whole is preferably within the above range.

<Resin sheet>
The resin sheet has a composition different from that of the first resin composition layer provided on the support side and the first resin composition layer provided on the side opposite to the support and forming the first resin composition layer. and a second resin composition layer formed of the second resin composition of

In the resin sheet with support of the present invention, the thickness of the resin sheet is preferably 3 μm or more, more preferably 5 μm or more. The upper limit of the thickness of the resin sheet is preferably 40 μm or less, more preferably 35 μm or less, still more preferably 30 μm or less, or 25 μm or less, from the viewpoint of setting the thickness of the resin layer on the conductor.

The thickness of the first resin composition layer made of the first resin composition is preferably 10 µm or less, more preferably 7 µm or less, and even more preferably 8 µm or less. The lower limit of the thickness of the first resin composition layer is not particularly limited, but from the viewpoint of obtaining an insulating layer exhibiting excellent peel strength with respect to the conductor layer after roughening treatment, and from the viewpoint of ease of production of the support-attached resin sheet. , typically 0.05 μm or more, 0.1 μm or more, and the like. The presence of the first resin composition layer can improve plating peelability.

The thickness of the second resin composition layer made of the second resin composition is preferably 2.5 μm or more, more preferably 5 μm or more, and still more preferably 7 μm or more, 8 μm or more, 9 μm or more, or 10 μm or more. The upper limit of the thickness of the second resin composition layer is preferably 30 μm or less, more preferably 25 μm or less, still more preferably 20 μm or less. Warpage can be suppressed by the presence of the second resin composition layer.

The support-attached resin sheet 10 of the present invention may further include a protective film on the surface of the resin sheet 12 that is not bonded to the support 11 (that is, the surface opposite to the support). The protective film contributes to preventing the surface of the resin sheet 12 from being dusted or scratched. As the material of the protective film, the same materials as those described for the support 11 may be used. Although the thickness of the protective film is not particularly limited, it is, for example, 1 μm to 40 μm. The support-attached resin sheet 10 can be used by peeling off the protective film when manufacturing a printed wiring board.

The thermal conductivity of the first thermoset obtained by thermally curing the first resin composition at 100° C. for 30 minutes and further at 190° C. for 90 minutes is preferably 1 W/mK or less, more preferably 0.7 W. /mK or less, more preferably 0.5 W/mK or less. Although the lower limit is not particularly limited, it can be 0.01 W/mK or more. The thermal conductivity can be measured according to the procedure of [Measurement of thermal conductivity of cured product] described later.

The thermal conductivity of the second thermoset obtained by thermally curing the second resin composition at 100° C. for 30 minutes and further at 190° C. for 90 minutes is preferably 1.5 W/mK or less, more preferably 1 0 W/mK or less, more preferably 0.7 W/mK or less. Although the lower limit is not particularly limited, it can be 0.01 W/mK or more. The thermal conductivity can be measured according to the procedure of [Measurement of thermal conductivity of cured product] described later.

In the present invention, the difference in thermal conductivity between the first and second thermosets is 0.4 W/mK or less. As described above, by setting the difference in thermal conductivity between the first and second thermosets to 0.4 W / mK or less, the length of the constricted portion generated in the extending direction of the interface of each hardened thermoset can be made smaller. This mechanism is considered to be due to uniform thermal decomposability of the first and second thermosets by laser due to a small difference in thermal conductivity between the first and second thermosets.

In the present invention, the difference in thermal conductivity between the first and second thermosets is 0.4 W/mK or less, preferably 0.35 W/mK or less, more preferably 0.3 W/mK or less. be. Although the lower limit is not particularly limited, it can be 0.01 W/mK or more.

The length of the gouged portion in the extending direction of the interface is defined as follows. When the vertical cross section of the via hole is observed, a straight line extrapolated to the side wall of the via hole is drawn, and the distance from the straight line to the interface between the first resin composition layer and the second resin composition layer is the length of the gouged portion. d. Specifically, the length of the gouged portion is determined by drawing a straight line such as an example shown in FIG. That's what I mean.

The length of the gouged portion is preferably 2.0 μm or less, more preferably 1.8 μm or less, even more preferably 1.5 μm or less, or 1.4 μm or less, from the viewpoint of suppressing the generation of voids during plating. . Although the lower limit is not particularly limited, it is 0.01 μm or more. The length of the gouged portion can be measured according to the procedure of "Confirmation of shape of via hole (evaluation of length of gouged portion and laser processability)" described later.

The support-attached resin sheet of the present invention can reduce the length of constricted portions that occur in the extending direction of the interfaces of each cured resin composition layer, so that the opening diameter (top diameter) is 40 μm or less. It also exhibits the property of being excellent in laser workability. This makes it possible to achieve finer wiring on the printed wiring board.

[Method for producing resin sheet with support]
An example of the method for producing the resin sheet with a support of the present invention will be described below.

First, a first resin composition layer made of a first resin composition and a second resin composition layer made of a second resin composition are formed on a support.

As a method of forming the first resin composition layer and the second resin composition layer, for example, there is a method of laminating the first resin composition layer and the second resin composition layer so as to bond them to each other. mentioned. As a method for laminating the first resin composition layer and the second resin composition layer so as to be bonded to each other, for example, the first resin composition is applied to the support, the coating film is dried, and the second resin composition layer is dried. After forming one resin composition layer, a second resin composition is applied onto the first resin composition layer, and the coating film is dried to provide a second resin composition layer.

In this method, for the first resin composition layer, a resin varnish is prepared by dissolving the first resin composition in an organic solvent, and this resin varnish is applied onto a support using a die coater or the like, and the resin is It can be made by drying the varnish.

Examples of organic solvents include ketones such as acetone, methyl ethyl ketone and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate; and carbitols such as cellosolve and butyl carbitol. aromatic hydrocarbons such as toluene and xylene; and amide solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone. An organic solvent may be used individually by 1 type, or may use 2 or more types together.

Drying of the resin varnish may be carried out by a known drying method such as heating or blowing hot air. Although it varies depending on the boiling point of the organic solvent in the resin varnish, for example, when using a resin varnish containing 30% by mass to 60% by mass of the organic solvent, drying at 50° C. to 150° C. for 1 minute to 10 minutes gives the support. A first resin composition layer can be formed thereon.

In the above method, the second resin composition layer is prepared by dissolving the second resin composition in an organic solvent to prepare a resin varnish, and using a die coater or the like to form this resin varnish on the support. can be prepared by coating on the resin composition layer of and drying the resin varnish.

As the organic solvent used for preparing the resin varnish in which the second resin composition is dissolved, the same organic solvent as used in preparing the resin varnish in which the first resin composition is dissolved can be used. The resin varnish in which the composition is dissolved can be dried by a method similar to the drying method for the resin varnish in which the first resin composition is dissolved.

In addition to the coating method described above, the resin sheet may be formed by a tandem coating method in which two types of resin varnishes are sequentially coated on one coating line. Moreover, the resin sheet can be prepared by a method of applying the first resin composition on the second resin composition layer and drying the coating film to form the first resin composition layer, and a separately prepared first resin composition layer. It can also be formed by a method of laminating the resin composition layer and the second resin composition layer so as to be bonded to each other.

Furthermore, in the present invention, for example, after forming the second resin composition layer and the first resin composition layer in order on the protective film, a support is laminated on the first resin composition layer to provide support. A body-attached resin sheet may be produced.

[Printed wiring board and method for manufacturing the printed wiring board]
The printed wiring board of the present invention includes an insulating layer formed from a cured resin sheet in the resin sheet with support of the present invention. Further, the method for manufacturing a printed wiring board of the present invention includes:
(I) Step of laminating the second resin composition layer of the resin sheet with the support of the present invention on the inner layer substrate so as to be bonded to the inner layer substrate (II) Thermosetting the resin sheet with the support to form an insulating layer and (III) forming via holes in the insulating layer and removing the support.

The "inner layer substrate" used in step (I) mainly means a substrate such as a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, or a substrate having A circuit board on which a patterned conductor layer (circuit) is formed. The term "inner layer substrate" as used in the present invention also includes an inner layer circuit board that is an intermediate product on which an insulating layer and/or a conductor layer are to be further formed when manufacturing a printed wiring board. When the printed wiring board is a component-embedded circuit board, an inner-layer substrate containing components may be used (a conductor layer is also called a wiring layer).

Lamination of the inner layer substrate and the support-attached resin sheet can be performed, for example, by heat-pressing the support-attached resin sheet to the inner layer substrate from the support side. Examples of the member for thermocompression bonding the support-attached resin sheet to the inner layer substrate (hereinafter also referred to as "thermocompression bonding member") include heated metal plates (such as SUS end plates) and metal rolls (SUS rolls). be done. It should be noted that instead of pressing the thermocompression member directly onto the resin sheet with the support, it is preferable to press through an elastic material such as heat-resistant rubber so that the resin sheet with the support can sufficiently follow the uneven surface of the inner layer substrate. preferable.

Lamination of the inner layer substrate and the resin sheet with support may be carried out by a vacuum lamination method. In the vacuum lamination method, the thermocompression temperature is preferably in the range of 60° C. to 160° C., more preferably 80° C. to 140° C., and the thermocompression pressure is preferably 0.098 MPa to 1.77 MPa, more preferably 0. .29 MPa to 1.47 MPa, and the heat pressing time is preferably 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. Lamination is preferably carried out under reduced pressure conditions of 26.7 hPa or less.

Lamination can be done with a commercially available vacuum laminator. Commercially available vacuum laminators include, for example, a vacuum pressurized laminator manufactured by Meiki Seisakusho Co., Ltd., a vacuum applicator manufactured by Nikko Materials Co., Ltd., and the like.

After lamination, the laminated resin sheets may be smoothed under normal pressure (atmospheric pressure), for example, by pressing a thermocompression member from the support side. The pressing conditions for the smoothing treatment may be the same as the thermocompression bonding conditions for the lamination described above. Smoothing treatment can be performed with a commercially available laminator. Lamination and smoothing may be performed continuously using the above-mentioned commercially available vacuum laminator.

In step (II), the resin sheet of the support-attached resin sheet is thermoset to form an insulating layer.

The thermosetting conditions for the resin sheets (first and second resin composition layers) are not particularly limited, and conditions commonly used for forming insulating layers of printed wiring boards may be used.

For example, the thermosetting conditions for the resin sheet differ depending on the types of the first and second resin compositions, etc., but the curing temperature is in the range of 120° C. to 240° C. (preferably 150° C. to 220° C., more preferably is in the range of 170° C. to 200° C.), and the curing time can be in the range of 5 minutes to 120 minutes (preferably 10 minutes to 100 minutes, more preferably 15 minutes to 90 minutes).

Before thermosetting the resin sheet, the resin sheet may be preheated at a temperature lower than the curing temperature. For example, prior to thermosetting the resin sheet, the resin sheet is heated for 5 minutes or more ( (preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes) may be preheated.

In step (III), via holes are formed in the insulating layer and the support is removed. Formation of the via hole is not particularly limited, and examples thereof include laser irradiation, etching, mechanical drilling, etc. Laser irradiation is preferable. From the viewpoint of further suppressing the generation of gouges, the support is preferably peeled off after the via hole is formed in the insulating layer. Specifically, the support is peeled off after the via hole is formed in the insulating layer with a laser. preferable.

This laser irradiation can be performed using any suitable laser processing machine using a carbon dioxide gas laser, a YAG laser, an excimer laser, or the like as a light source. Laser processing machines that can be used include, for example, CO ₂ laser processing machine "LC-2k212/2C" manufactured by Via Mechanics Co., Ltd., 605GTWIII (-P) manufactured by Mitsubishi Electric Corporation, and manufactured by Matsushita Welding Systems Co., Ltd. laser processing machine.

The conditions for laser irradiation are not particularly limited, and laser irradiation can be carried out by any suitable process according to conventional methods according to the means selected.

The shape of the via hole, that is, the shape of the contour of the opening when viewed in the extending direction is not particularly limited, but is generally circular (substantially circular). Hereinafter, the "diameter" of the via hole means the diameter of the contour of the opening when viewed in the extending direction. In this specification, the opening diameter (top diameter) refers to the diameter of the contour of the via hole on the insulating layer (cured product of the first resin composition layer) side, and the bottom diameter r2 refers to the contour of the via hole on the wiring layer side. Say the diameter.

The opening diameter r1 of the via hole is preferably 40 μm or less, more preferably 35 μm or less, still more preferably 30 μm or less, or preferably 25 μm or less.

The via hole may be formed so that the opening diameter r1 is larger than the bottom diameter r2, or the via hole may be formed so that the opening diameter r1 and the bottom diameter r2 of the via hole are the same. In this way, the embedding property of the via hole is improved, and the generation of voids can be suppressed.

When manufacturing a printed wiring board, (IV) the step of roughening the insulating layer and (V) the step of forming the conductor layer may be further carried out. These steps (IV) to (V) may be carried out according to various methods known to those skilled in the art for use in manufacturing printed wiring boards.

Step (IV) is a step of roughening the insulating layer. The procedure and conditions of the roughening treatment are not particularly limited, and known procedures and conditions that are commonly used in forming insulating layers of printed wiring boards can be employed. For example, the insulating layer can be roughened by performing a swelling treatment with a swelling liquid, a roughening treatment with an oxidizing agent, and a neutralizing treatment with a neutralizing liquid in this order. The swelling liquid is not particularly limited, but may be an alkaline solution, a surfactant solution, or the like, preferably an alkaline solution, and more preferably a sodium hydroxide solution or a potassium hydroxide solution. Examples of commercially available swelling liquids include "Swelling Dip Securigans P" and "Swelling Dip Securigans SBU" manufactured by Atotech Japan. The swelling treatment with the swelling liquid is not particularly limited, but can be performed, for example, by immersing the insulating layer in the swelling liquid at 30.degree. C. to 90.degree. C. for 1 to 20 minutes. From the viewpoint of suppressing swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the cured product in a swelling liquid at 40° C. to 80° C. for 5 minutes to 15 minutes. The oxidizing agent (roughening liquid) is not particularly limited, but examples thereof include an alkaline permanganate solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. The roughening treatment with an oxidizing agent such as an alkaline permanganate solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60° C. to 80° C. for 10 to 30 minutes. Further, the permanganate concentration in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as "Concentrate Compact CP", "Concentrate Compact P", and "Dosing Solution Security P" manufactured by Atotech Japan Co., Ltd. mentioned. Moreover, as a neutralization liquid, an acidic aqueous solution is preferable, and as a commercial product, for example, "Reduction Solution Securigant P" manufactured by Atotech Japan Co., Ltd. can be mentioned. The treatment with the neutralizing solution can be carried out by immersing the treated surface roughened with the oxidizing agent in the neutralizing solution at 30° C. to 80° C. for 5 to 30 minutes. From the viewpoint of workability, etc., a method of immersing an object roughened with an oxidizing agent in a neutralizing solution at 40° C. to 70° C. for 5 to 20 minutes is preferable.

Step (V) is a step of forming a conductor layer.

The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer contains one or more selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. Contains metal. The conductor layer may be a single metal layer or an alloy layer, and the alloy layer may be, for example, an alloy of two or more metals selected from the above group (for example, a nickel-chromium alloy, a copper- nickel alloys and copper-titanium alloys). Among them, from the viewpoint of versatility of conductor layer formation, cost, ease of patterning, etc., single metal layers of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, nickel-chromium alloys, copper- Nickel alloys and copper/titanium alloy alloy layers are preferred, and single metal layers of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or nickel/chromium alloy alloy layers are more preferred, and copper single metal layers are preferred. A metal layer is more preferred.

The conductor layer may have a single layer structure or a multi-layer structure in which two or more single metal layers or alloy layers made of different kinds of metals or alloys are laminated. When the conductor layer has a multilayer 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 nickel-chromium alloy.

The thickness of the conductor layer is generally between 3 μm and 35 μm, preferably between 5 μm and 30 μm, depending on the desired printed wiring board design.

In one embodiment, the conductor layer may be formed by plating. For example, a conductive layer having a desired wiring pattern can be formed by plating the surface of the insulating layer by a conventionally known technique such as a semi-additive method or a full-additive method. An example of forming a conductor layer by a semi-additive method is shown below.

First, a plating seed layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern is formed on the formed plating seed layer to expose a portion of the plating seed layer corresponding to a desired wiring pattern. After forming a metal layer on the exposed plating seed layer by electroplating, the mask pattern is removed. After that, the unnecessary plating seed layer is removed by etching or the like, and a conductor layer having a desired wiring pattern can be formed.

[Semiconductor device]
A semiconductor device of the present invention includes the printed wiring board of the present invention. The semiconductor device of the present invention can be manufactured using the printed wiring board of the present invention.

Examples of semiconductor devices include various semiconductor devices used in electrical appliances (eg, computers, mobile phones, digital cameras, televisions, etc.) and vehicles (eg, motorcycles, automobiles, trains, ships, aircraft, etc.).

The semiconductor device of the present invention can be manufactured by mounting a component (semiconductor chip) on a conductive portion of a printed wiring board. A "conducting part" is a "part where an electric signal is transmitted on a printed wiring board", and the place may be a surface or an embedded part. Also, the semiconductor chip is not particularly limited as long as it is an electric circuit element made of a semiconductor.

The method of mounting the semiconductor chip when manufacturing the semiconductor device of the present invention is not particularly limited as long as the semiconductor chip functions effectively. Examples include a mounting method using a buildup layer (BBUL), a mounting method using an anisotropic conductive film (ACF), and a mounting method using a non-conductive film (NCF). Here, "a mounting method using a build-up layer without bumps (BBUL)" means "a mounting method in which a semiconductor chip is directly embedded in a concave portion of a printed wiring board and the semiconductor chip and wiring on the printed wiring board are connected." is.

EXAMPLES The present invention will be specifically described below by way of examples, but the present invention is not limited to these examples. In the following description, "parts" and "%" mean "mass parts" and "mass%", respectively, unless otherwise specified.

[Preparation of resin sheet with support]
Using a resin varnish (resin composition) prepared by the following procedure, resin sheets with supports of Examples and Comparative Examples were produced.

(Preparation of resin varnish 1)
Bixylenol type epoxy resin (Mitsubishi Chemical Co., Ltd. "YX4000HK", epoxy equivalent about 185) 10 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC3000L", epoxy equivalent 288) 25 parts, and phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of cyclohexanone with a solid content of 30% by mass: methyl ethyl ketone (MEK)) is heated and dissolved in a mixed solvent of 5 parts of solvent naphtha and 5 parts of cyclohexanone while stirring. let me After cooling to room temperature, 10 parts of a triazine skeleton-containing phenol novolac curing agent (hydroxyl equivalent 125, "LA-7054" manufactured by DIC Corporation, MEK solution with a solid content of 60%) and a biphenyl novolac curing agent are added thereto. (Hydroxyl equivalent 218, Meiwa Kasei Co., Ltd. "MEH-7851H", solid content 60% MEK solution) 15 parts, polyvinyl butyral resin (glass transition temperature 105 ° C., Sekisui Chemical Co., Ltd. "KS-1" 1:1 mixed solution of ethanol and toluene with a solid content of 15%) 10 parts of an amine curing accelerator (4-dimethylaminopyridine (DMAP), a MEK solution with a solid content of 5% by mass) 1 part, imidazole curing Accelerator (“P200-H50” manufactured by Mitsubishi Chemical Co., Ltd., propylene glycol monomethyl ether solution with a solid content of 50% by mass) 2 parts, surface treatment with aminosilane coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) 22 parts of spherical silica ("SPH516-05" manufactured by Nippon Steel & Sumikin Materials Co., Ltd., average particle size 0.2 μm, carbon amount per unit surface area 0.43 mg/m ² ) was mixed and mixed uniformly with a high-speed rotating mixer. and then filtered through a cartridge filter ("SHP020" manufactured by ROKITECHNO) to prepare resin varnish 1.

(Preparation of resin varnish 2)
Bisphenol F type epoxy resin (Mitsubishi Chemical Co., Ltd. "1750", epoxy equivalent about 159) 5 parts, bixylenol type epoxy resin (Mitsubishi Chemical Co., Ltd. "YX4000HK", epoxy equivalent about 185) 10 parts, biphenyl type Epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 288) 20 parts, naphthalene type epoxy resin (DIC Corporation "HP-4710", epoxy equivalent about 170) 3 parts, and phenoxy resin (Mitsubishi 5 parts of "YX7553BH30" manufactured by Kagaku Co., Ltd., a 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) having a solid content of 30% by mass) was heated and dissolved in a mixed solvent of 20 parts of solvent naphtha and 5 parts of cyclohexanone while stirring. . After cooling to room temperature, 5 parts of a triazine skeleton-containing phenol novolac curing agent (hydroxyl equivalent 125, "LA-7054" manufactured by DIC Corporation, MEK solution with a solid content of 60%), and a triazine skeleton-containing cresol novolak are added thereto. System curing agent (hydroxyl equivalent 151, DIC Corporation "LA-3018-50P", solid content 50% 2-methoxypropanol solution) 10 parts, naphthol curing agent (Nippon Steel & Sumikin Chemical Co., Ltd. "SN485" , hydroxyl equivalent 215, solid content 60% MEK solution) 10 parts, amine curing accelerator (4-dimethylaminopyridine (DMAP), solid content 5% by weight MEK solution) 1 part, flame retardant (Sanko Co., Ltd. "HCA-HQ", 10-(2,5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide, average particle size 1.5 μm) 3 parts, aminosilane system Spherical silica surface-treated with a coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) ("SP60-05" manufactured by Nippon Steel & Sumikin Materials Co., Ltd., average particle size 1.3 μm, amount of carbon per unit surface area 0.30 mg/m ² ) were mixed, and after uniformly dispersing with a high-speed rotating mixer, the mixture was filtered with a cartridge filter ("SHP050" manufactured by ROKITECHNO) to prepare resin varnish 2.

(Preparation of resin varnish 3)
Naphthalene type epoxy resin (epoxy equivalent 144, DIC Corporation "HP4032SS") 5 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC3100", epoxy equivalent 258) 5 parts, naphthylene ether type epoxy resin ("EXA-7311" manufactured by DIC Corporation, epoxy equivalent 277) 20 parts, and phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, cyclohexanone having a solid content of 30% by mass: 1:1 solution of methyl ethyl ketone (MEK) ) was heated and dissolved in a mixed solvent of 5 parts of solvent naphtha and 5 parts of cyclohexanone with stirring. After cooling to room temperature, 5 parts of an active ester compound ("HPC-8000-65T" manufactured by DIC Corporation, a toluene solution with a weight average molecular weight of about 2700 and an active group equivalent of about 223 and a non-volatile content of 65% by mass), carbodiimide Resin ("V-03" manufactured by Nisshinbo Chemical Co., Ltd., a toluene solution of 50% by mass of non-volatile components) 5 parts, prepolymer of bisphenol A dicyanate ("BA230S75" manufactured by Lonza Japan Co., Ltd., cyanate equivalent about 232, non-volatile 75 wt% MEK solution) 30 parts, curing accelerator (4-dimethylaminopyridine (DMAP), solid content 5 wt% MEK solution) 1 part, imidazole curing accelerator (manufactured by Mitsubishi Chemical Corporation "P200- H50", propylene glycol monomethyl ether solution with a solid content of 50% by mass) 0.1 part, curing accelerator (manufactured by Tokyo Kasei Co., Ltd., cobalt (III) acetylacetonate [Co (III) Ac, solid content 1% by mass MEK solution] 3 parts, rubber particles (PARALOID EXL2655, manufactured by Dow Chemical Japan Co., Ltd.) 2 parts, spherical particles surface-treated with a phenylaminosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573") 12 parts of silica (“SPH516-05” manufactured by Nippon Steel & Sumikin Materials Co., Ltd., average particle size 0.2 μm, carbon amount per unit surface area 0.43 mg/m ² ) was mixed and uniformly dispersed with a high-speed rotating mixer. After that, it was filtered through a cartridge filter (“SHP020” manufactured by ROKITECHNO) to prepare a resin varnish 3.

(Preparation of resin varnish 4)
10 parts of bisphenol A type epoxy resin ("825" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 176), 20 parts of naphthylene ether type epoxy resin ("EXA-7311" manufactured by DIC Corporation, epoxy equivalent of 277), and While stirring 12 parts of a phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) with a solid content of 30% by mass) in a mixed solvent of 12 parts of solvent naphtha and 5 parts of cyclohexanone. Dissolved by heating. After cooling to room temperature, 30 parts of an active ester compound ("HPC-8000-65T" manufactured by DIC Corporation, a toluene solution with a weight average molecular weight of about 2700 and an active group equivalent of about 223 and a non-volatile content of 65% by mass) and cured. Accelerator (4-dimethylaminopyridine, MEK solution with a solid content of 5% by mass) 2 parts, imidazole-based curing accelerator (manufactured by Shikoku Kasei Co., Ltd. "1B2PZ" 1-benzyl-2-phenylimidazole, solid content 5% MEK solution) 0.5 parts, flame retardant ("HCA-HQ" manufactured by Sanko Co., Ltd., 10-(2,5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene- 10-oxide, average particle size 2 μm) 3 parts, spherical silica (“SP507-05” manufactured by Nippon Steel & Sumikin Materials Co., Ltd.) surface-treated with an aminosilane coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) , an average particle size of 1.0 μm, and a carbon amount per unit surface area of 0.35 mg/m ² ) were mixed, and after uniformly dispersing with a high-speed rotating mixer, filtered through a cartridge filter (“SHP050” manufactured by ROKITECHNO). , Resin Varnish 4 was prepared.

(Preparation of resin varnish 5)
Bisphenol F type epoxy resin (Mitsubishi Chemical Co., Ltd. "1750", epoxy equivalent about 159) 5 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC3000L", epoxy equivalent 288) 20 parts, biphenyl type epoxy Resin (Nippon Kayaku Co., Ltd. "NC3100", epoxy equivalent 258) 3 parts, and phenoxy resin (Mitsubishi Chemical Co., Ltd. "YX7553BH30", cyclohexanone with a solid content of 30% by mass: methyl ethyl ketone (MEK) 1: 1 Solution) was heated and dissolved in a mixed solvent of 5 parts of solvent naphtha and 5 parts of cyclohexanone while stirring. After cooling to room temperature, 5 parts of a triazine skeleton-containing cresol novolac curing agent (hydroxyl equivalent of 151, "LA-3018-50P" manufactured by DIC Corporation, 2-methoxypropanol solution with a solid content of 50%), Active ester compound (manufactured by DIC Corporation "HPC-8000-65T", weight average molecular weight of about 2700, active group equivalent weight of about 223, nonvolatile content of 65 wt% toluene solution) 15 parts, amine curing accelerator (4- Dimethylaminopyridine (DMAP), MEK solution with a solid content of 5% by mass) 2 parts, imidazole-based curing accelerator (manufactured by Shikoku Kasei Co., Ltd. "1B2PZ" 1-benzyl-2-phenylimidazole, MEK with a solid content of 5% solution) 2 parts, epoxysilane coupling agent (Shin-Etsu Chemical Co., Ltd. "KBM403") 0.1 part, fine powder silicon carbide (Shinano Electric Refining Co., Ltd. "SER-A06", average particle size 0 0.6 μm) was mixed, uniformly dispersed in a high-speed rotating mixer, and then filtered through a cartridge filter ("SHP030" manufactured by ROKITECHNO) to prepare a resin varnish 5.

(Preparation of resin varnish 6)
Bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd. "825", epoxy equivalent about 176) 10 parts, xylene type epoxy resin (Mitsubishi Chemical Co., Ltd. "YX7700", epoxy equivalent 270) 25 parts, and phenoxy resin ( 20 parts of "YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) having a solid content of 30% by mass) was heated and dissolved in a mixed solvent of 5 parts of solvent naphtha and 5 parts of cyclohexanone while stirring. rice field. After cooling to room temperature, 10 parts of a triazine skeleton-containing phenol novolac curing agent (hydroxyl equivalent 125, DIC Corporation "LA-7054", solid content 60% MEK solution), a naphthol curing agent (Nippon Steel & Sumikin Chemical Co., Ltd. "SN485", hydroxyl equivalent 215, solid content 60% MEK solution) 15 parts, polyvinyl butyral resin (glass transition temperature 105 ° C., Sekisui Chemical Co., Ltd. "KS-1") solid content 15 % ethanol and toluene 1:1 mixed solution) 10 parts of amine curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with solid content of 5% by mass) 1 part, imidazole curing accelerator (Mitsubishi Chemical Co., Ltd. “P200-H50”, propylene glycol monomethyl ether solution with a solid content of 50% by mass) 2 parts, spherical silica surface-treated with an aminosilane coupling agent (Shin-Etsu Chemical Co., Ltd. “KBM573”) 22 parts of ("SO-C1" manufactured by Admatechs Co., Ltd., average particle size 0.4 μm, carbon amount per unit surface area 0.35 mg/m ² ) were mixed and uniformly dispersed with a high-speed rotating mixer, and then the cartridge was mixed. A resin varnish 6 was prepared by filtering through a filter (“SHP030” manufactured by ROKITECHNO).

(Preparation of resin varnish 7)
Bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd. "825", epoxy equivalent about 176) 5 parts, bixylenol type epoxy resin (Mitsubishi Chemical Co., Ltd. "YX4000HK", epoxy equivalent about 185) 10 parts, biphenyl type Epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 288) 20 parts, naphthalene type epoxy resin (DIC Corporation "HP-4710", epoxy equivalent about 170) 3 parts, and phenoxy resin (Mitsubishi Chemical Co., Ltd. "YX7553BH30", 1:1 solution of cyclohexanone: methyl ethyl ketone (MEK) with a solid content of 30% by mass) was dissolved in a mixed solvent of 10 parts of solvent naphtha and 5 parts of cyclohexanone by heating while stirring. . After cooling to room temperature, 5 parts of a triazine skeleton-containing phenol novolac curing agent (hydroxyl equivalent 125, "LA-7054" manufactured by DIC Corporation, MEK solution with a solid content of 60%), and a triazine skeleton-containing cresol novolak are added thereto. system curing agent (hydroxyl equivalent 151, DIC Corporation "LA3018-50P", solid content 50% 2-methoxypropanol solution) 10 parts, naphthol curing agent (Nippon Steel & Sumikin Chemical Co., Ltd. "SN485", hydroxyl group equivalent weight 215, solid content 60% MEK solution) 10 parts, amine curing accelerator (4-dimethylaminopyridine (DMAP), solid content 5% by mass MEK solution) 1 part, flame retardant (manufactured by Sanko Co., Ltd. "HCA-HQ", 10-(2,5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide, average particle size 1.5 μm) 3 parts, aminosilane-based coupling Crushed silica (“IMSIL A-8” manufactured by Tatsumori Co., Ltd.) surface-treated with an agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.), average particle size 2 μm, carbon amount per unit surface area 0.21 mg / m ² ) After mixing 120 parts and dispersing them uniformly with a high-speed rotating mixer, they were filtered through a cartridge filter ("SHP050" manufactured by ROKITECHNO) to prepare resin varnish 7.

Table 1 shows the materials used in the production of each resin varnish and their compounding amounts (mass parts of non-volatile matter).

<Example 1: Production of resin sheet with support>
As a support, a PET film (“Lumirror R80” manufactured by Toray Industries, Inc., thickness 38 μm, softening point 130 ° C., “release type PET") was prepared.

The resin varnish 1 is uniformly applied on the release PET with a die coater so that the thickness of the first resin composition layer after drying is 5 μm, and dried at 80° C. to 160° C. for 5 minutes. A first resin composition layer was obtained on the release PET. Next, the resin varnish 2 is applied on the first resin composition layer so that the thickness combined with the first resin composition layer after drying is 20 μm, and is heated to 70° C. to 110° C. (average 90° C.). and dried for 3 minutes to form a two-layered resin composition layer (resin sheet). Next, a polypropylene film (Oji F-Tex Co., Ltd. ) manufactured by “Alphan MA-411”, thickness 15 μm) was laminated so as to be bonded to the second resin composition layer. As a result, a support-attached resin sheet 1 consisting of a support, a first resin composition layer (derived from resin varnish 1), a second resin composition layer (derived from resin varnish 2), and a protective film in this order was obtained. .

<Example 2: Production of resin sheet 2 with support>
In Example 1, 1) resin varnish 3 was used instead of resin varnish 1, and was applied so that the thickness of the first resin composition layer after drying was 3 μm, and 2) resin varnish 4 was used instead of resin varnish 2. A support-attached resin sheet 2 was obtained in the same manner as in Example 1, except that it was used.

<Example 3: Production of resin sheet 3 with support>
In Example 1, 1) resin varnish 5 was used instead of resin varnish 1, and was applied so that the thickness of the first resin composition layer after drying was 4 μm, and 2) resin varnish 4 was used instead of resin varnish 2. A support-attached resin sheet 3 was obtained in the same manner as in Example 1, except that it was used.

<Comparative Example 1: Production of resin sheet 4 with support>
Resin sheet with a support in the same manner as in Example 1, except that resin varnish 6 was used instead of resin varnish 1, and the thickness of the first resin composition layer after drying was 4 μm. Got 4.

<Comparative Example 2: Production of resin sheet 5 with support>
A support-attached resin sheet 5 was obtained in the same manner as in Example 1, except that resin varnish 7 was used instead of resin varnish 2 in Example 1.

(Preparation of cured product of each resin composition)
Each of the resin varnishes 1 to 7 was applied uniformly with a die coater on the same release PET film as in Examples and Comparative Examples so that the thickness of the resin composition layer after drying was 50 μm, and the temperature was 70° C. to 120° C. was dried for 5 minutes to obtain a resin film in which a resin composition layer was formed on a release PET film.

The untreated surface of the release PET film ("501010" manufactured by Lintec Co., Ltd., thickness 38 μm, 240 mm square) is a glass cloth-based epoxy resin double-sided copper clad laminate (manufactured by Matsushita Electric Works Co., Ltd. "R5715ES", thickness 0.7 mm, 255 mm square), and the four sides of the release film were fixed with a polyimide adhesive tape (width 10 mm).

Each resin film (167 × 107 mm square) having a resin composition layer thickness of 50 µm is coated with a batch type vacuum pressure laminator (2-stage build-up laminator CVP700 manufactured by Nikko Materials Co., Ltd.) to form a resin composition layer. was laminated in the center so that the was in contact with the release surface of the release PET film. The lamination process was carried out by pressure bonding for 30 seconds at 100° C. and pressure of 0.74 MPa after reducing the pressure to 13 hPa or less for 30 seconds.

Next, the support was peeled off, and a resin composition layer of the same resin film was further laminated on the resin composition layer under the same conditions to form a resin composition layer having a thickness of 50 μm×2=100 μm, and then the support was peeled off. In this state, the resin composition layer was thermally cured under curing conditions of 100° C. for 30 minutes and 190° C. for 90 minutes.

After thermal curing, the polyimide adhesive tape was peeled off, and the resin composition layer was removed from the glass cloth-based epoxy resin double-sided copper-clad laminate. Further, the release PET film was peeled off from the resin composition layer to obtain a sheet-like cured product having a thickness of about 100 μm. The sheet-like cured product is called a cured product for evaluation.

[Measurement of thermal conductivity of cured product]
(1) Measurement of thermal diffusivity α The thermal diffusivity α (m ² /s) in the thickness direction of the cured product for evaluation was measured by temperature wave analysis using “ai-Phase Mobile 1u” manufactured by ai-Phase. It was measured. The same sample was measured three times, and the average value was calculated.
(2) Measurement of specific heat capacity Cp Using a differential scanning calorimeter ("DSC7020" manufactured by SII Nano Technology Co., Ltd.), the temperature is increased from -40 ° C. to 80 ° C. at a rate of 10 ° C./min and measured to cure. The specific heat capacity Cp (J/kg·K) of the material sample at 20°C was calculated.
(3) Measurement of Density ρ The density (kg/m ³ ) of the cured product for evaluation was measured using an analytical balance XP105 (using a specific gravity measurement kit) manufactured by Mettler Toledo.
(4) Calculation of thermal conductivity λ Thermal diffusivity α (m ² /s), specific heat capacity Cp (J/kg K), and density ρ (kg/m ³ ) was substituted into the following formula (I) to calculate the thermal conductivity λ (W/m·K). The results are shown in the table below.
λ=α×Cp×ρ (I)

<Evaluation of gouge length and laser processability>
(Preparation of sample)
(1) Surface treatment of wiring substrate A glass cloth-based epoxy resin laminate (copper foil thickness 12 μm, substrate thickness 0.3 mm, size 510 mm × 340 mm, on both sides of a wiring board on which a conductor pattern (residual copper rate of about 70%) is formed using "R-1515A" manufactured by Panasonic Corporation), treatment (i) "CZ8101" manufactured by MEC Co., Ltd. was removed by etching to a thickness of about 0.8 .mu.m, and the surface of the conductor pattern was roughened.

(2) Resin sheet lamination process Each support-attached resin sheet (size 504 mm × 334 mm) having a two-layer resin composition prepared in Examples and Comparative Examples is peeled off and a batch type vacuum pressure laminator ( Nikko Materials Co., Ltd., 2-stage build-up laminator, CVP700), so that the second resin composition layer is in contact with the wiring board treated in (1) above, laminated on both sides of the wiring board. did. This lamination step was carried out by pressure bonding for 30 seconds at a temperature of 120° C. and a pressure of 0.74 MPa after reducing the pressure to 13 hPa or less for 30 seconds. Then, a hot press process was performed for 60 seconds under conditions of a temperature of 110° C. and a pressure of 0.5 MPa.

(3) Curing of Resin Composition Layer The wiring board on which the resin sheet with the support is laminated is heat-cured under the curing conditions of 100° C. for 30 minutes and then 175° C. for 30 minutes to cure the resin composition layer to form an insulating layer ( about 15 μm thick) on the conductor.

(4) Formation of Via Hole A laser was irradiated from above the support side to form a small diameter via hole in the insulating layer immediately above the inner circular conductor pattern with a diameter of 150 μm to obtain an evaluation substrate.

The via hole forming process was performed under the conditions shown below.
A via hole having a top diameter (diameter) of 30 μm was formed in the insulating layer by irradiating a laser from above the support side using a CO ₂ laser processing machine “605GTWIII(-P)” manufactured by Mitsubishi Electric Corporation. The laser irradiation conditions were a mask diameter of 1 mm, a pulse width of 16 μs, an energy of 0.20 mJ/shot, two shots, and burst mode (10 kHz).

(evaluation)
(5) Confirmation of via hole shape (evaluation of gouge length and laser processability)
The substrate for evaluation obtained in (4) above was peeled off from the support, cut to an appropriate size, and the sample including the via hole was embedded in a cold embedding resin. -22), and observed with a scanning electron microscope (S4800 manufactured by Hitachi High-Technologies Corporation). From the obtained image, the length (μm) of the gouged portion generated in the extending direction of the interface generated at the interface between the first resin composition layer and the second resin composition layer was measured. Specifically, a straight line extrapolated to the side wall of the via hole was drawn, and the distance d from the straight line to the interface between the first resin composition layer and the second resin composition layer was measured. Four via holes were measured, average values were obtained, and evaluation was made according to the following criteria.
○: The length of the gouged portion is 3 μm or less ×: The length of the gouged portion exceeds 3 μm

10 resin sheet with support 11 support 12 resin sheet 13 first resin composition layer 14 second resin composition layer

Claims (12)

A support-attached resin sheet comprising a support and a resin sheet provided on the support,
The resin sheet includes a first resin composition layer formed of a first resin composition and provided on the support side;
a second resin composition layer formed of a second resin composition provided on the side opposite to the support side,
The thickness of the first resin composition layer is 3 μm or more,
The first resin composition contains (a) an inorganic filler, and the content of component (a) is 30% by mass or less when the non-volatile component in the first resin composition is 100% by mass. ,
The second resin composition contains (a) an inorganic filler, and the content of component (a) is 60% by mass or more when the non-volatile component in the second resin composition is 100% by mass. ,
The thermal conductivity of the first thermoset obtained by thermally curing the first resin composition at 100 ° C. for 30 minutes and further at 190 ° C. for 90 minutes, and the second resin composition at 100 ° C. for 30 minutes, A resin sheet with a support having a thermal conductivity difference of 0.4 W/mK or less from that of a second thermoset obtained by further thermosetting at 190° C. for 90 minutes. 2. The resin sheet with a support according to claim 1, wherein the resin sheet has a thickness of 40 [mu]m or less. 3. The resin sheet with a support according to claim 1, wherein the resin sheet has a thickness of 25 [mu]m or less. When the average particle size of component (a) in the first resin composition is R1 (μm) and the average particle size of component (a) in the second resin composition is R2 (μm), R1 and R2 The resin sheet with a support according to any one of claims 1 to 3, wherein the ratio (R2/R1) is 1 to 15. The resin sheet with a support according to any one of claims 1 to 4, wherein the first resin composition contains (b) an epoxy resin, and the component (b) has a mesogenic skeleton. (b) component is one or more selected from bixylenol-type epoxy resin, bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, biphenyl-type epoxy resin, and naphthalene-type epoxy resin, according to claim 5. Resin sheet with support. 7. The support-attached resin sheet according to claim 1, which is used for forming an insulating layer of a printed wiring board. (I) A step of laminating the second resin composition layer of the resin sheet with the support according to any one of claims 1 to 7 on the inner layer substrate so as to be bonded to the inner layer substrate (II) Support and (III) forming via holes in the insulating layer and removing the support. 9. The method for manufacturing a printed wiring board according to claim 8, wherein in step (III), via holes are formed in the insulating layer by laser. 10. The method for producing a printed wiring board according to claim 8, wherein the via hole has an opening diameter of 40 [mu]m or less. A printed wiring board comprising an insulating layer formed of the support-attached resin sheet according to any one of claims 1 to 7. A semiconductor device comprising the printed wiring board according to claim 11 .

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