KR20150098217A - Resin sheet with support - Google Patents

Abstract

The present invention provides a technique capable of forming an insulating layer showing an excellent peel strength for a conductive layer after a roughness treatment while maintaining characteristics of a bulk, known to have a high content of an inorganic filler. A resin sheet attached with a support comprises: a support; and a resin composition layer containing an inorganic filler having 50 wt% or more and being in contact with the support. In a cross-section of the resin composition layer in the perpendicular direction of the surface of the support, the resin sheet attached with a support satisfies a relationship of A0-1/A1-2 > 1.1 wherein a resin area A0-1 is for an area having a distance of 0 to 1 μm from a boundary of the support and the resin composition layer and wherein a resin area A1-2 is for an area having a distance of 1 to 2 μm from the boundary.

Description

RESIN SHEET WITH SUPPORT [0002]

The present invention relates to a resin sheet with a support.

As a manufacturing technique of a printed wiring board, a manufacturing method by a build-up method in which an insulating layer and a conductor layer are alternately laminated is known. In the build-up method, generally, the insulating layer is formed by thermally curing the resin composition. For example, in Patent Document 1, a resin composition layer is laminated on an inner layer substrate using a resin sheet with a support including a support and a resin composition layer containing silica particles provided on the support, And curing the resulting cured product to roughen the resulting cured product to form an insulating layer.

There is a tendency that the number of stacked layers due to the buildup of the printed wiring board tends to increase while the number of stacked layers increases. However, cracks due to the difference in thermal expansion between the insulating layer and the conductor layer, This becomes a problem. As a technique for suppressing the problem of such cracks and circuit deformation, for example, Patent Document 2 discloses a technique of suppressing the thermal expansion rate of the insulating layer formed to be low by increasing the content of inorganic fillers such as silica particles in the resin composition .

International Publication No. 2010/35451 Japanese Patent Application Laid-Open No. 2010-202865

In the technique described in Patent Document 1, the silica particles on the surface of the cured body are removed in the roughening treatment, thereby realizing an insulating layer exhibiting sufficient peel strength with respect to the conductor layer. However, if a resin composition having a high content of an inorganic filler such as silica particles is used to form an insulating layer having a low thermal expansion rate, even in such a case, if the deterioration of the peeling strength between the insulating layer and the conductor layer to be formed can not be avoided .

An object of the present invention is to provide a technique capable of forming an insulating layer exhibiting excellent peel strength with respect to a conductor layer after a roughening treatment while retaining the bulk property that the content of the inorganic filler is high.

As a result of intensive studies on the above problems, the inventors of the present invention have found that when a gradient (an amount of inorganic filler / resin component) in the ratio of the inorganic filler to the resin component (inorganic filler / resin component) in the region near the surface of the support And a resin composition layer containing a resin composition layer having a positive gradient of at least a predetermined value toward the thickness direction). The present invention has been accomplished based on these findings.

That is, the present invention includes the following contents.

[1] A resin sheet with a support comprising a support and a resin composition layer bonded to the support and having an inorganic filler content of 50 mass% or more,

In the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area A _0-1 in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 1 탆, The resin area A _1-2 in the region of from 1 탆 to 2 탆 satisfies the relationship of A _0-1 / A _1-2 > 1.1.

[2] A resin sheet with a support comprising a support and a resin composition layer bonded to the support and having an inorganic filler content of 50 mass% or more,

In the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area A _0-0.5 in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 0.5 탆, Is in the range of 0.5 占 퐉 to 1 占 퐉, the resin area A _0.5-1 satisfies the relation of A _0-0.5 / A _0.5-1 > 1.1.

[3] The resin composition according to any one of [1] to [2], wherein in the cross section of the resin composition layer in the direction perpendicular to the surface of the support, resin a _0.5-d area and the area a _{d -0.5D} resin in a region where the distance from the boundary to from _{d㎛ 0.5D㎛, 0.9 ≤ kA 0 .5} -d / a d -0.5D ≤ 1.1 D is a number satisfying 0.5 &lt; d < 0.5D, and D is a thickness of the resin composition layer), the relationship of k is a relation satisfying k = | d-0.5D | /0.5-d | Of the resin sheet.

[4] A method for manufacturing a semiconductor device, comprising the steps of: providing a first layer made of a first resin composition having a thickness of less than 2 탆 and a second layer made of a second resin composition to be bonded to each other to form an integrated resin composition layer;

The content of the inorganic filler in the resin composition layer is 50% by mass or more,

The surface of the side of the resin composition layer originated from the first layer is bonded to the support,

In the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area A _0-1 in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 1 탆, Wherein the resin area A _1-2 in the region of from 1 占 퐉 to 2 占 퐉 satisfies the relationship of A _0-1 / A _1-2 > 1.1.

[5] The method according to [4], wherein the step of forming the resin composition layer comprises:

(A1) a step of preparing a temporary resin sheet with a support comprising a support and a first layer having a thickness of less than 2 mu m made of a first resin composition bonded to the support, and

(B1) applying a second resin composition onto the first layer, and drying the coated film to provide a second layer, thereby forming an integrated resin composition layer.

[6] The method according to [4] or [5], wherein the thickness of the first layer is less than 1 탆.

[7] The method according to any one of [4] to [6], wherein the first resin composition comprises an inorganic filler having an average particle diameter of 500 nm or less.

[8] The method according to any one of [4] to [7], wherein the content of the inorganic filler in the first resin composition is 40% by mass or less.

[9] The method according to any one of [4] to [8], wherein the content of the inorganic filler in the second resin composition is higher than 50 mass%.

[10] A printed wiring board comprising an insulating layer formed using the resin sheet with a support according to any one of [1] to [3].

[11] A semiconductor device comprising a printed wiring board according to [10].

According to the resin sheet with a support of the present invention, it is possible to form an insulating layer exhibiting excellent peel strength with respect to the conductor layer after the roughening treatment while retaining bulk characteristics that the content of the inorganic filler is high.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic diagram for explaining a method of calculating a resin area ratio (kA _{d1 - d2} / A _{d2 - d3} ratio).

Before describing in detail the resin sheet with the support of the present invention, the "first resin composition" and the "second resin composition" used in forming the resin composition layer contained in the resin sheet with the support of the present invention do.

&Lt; First Resin Composition >

The first resin composition is used to form a region in the resin composition layer near the bonding surface with the support.

The first resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, and the cured product of the first resin composition may have sufficient hardness and insulating properties. Examples of such a resin composition include a composition containing a curable resin and a curing agent thereof. As the curable resin, conventionally known curable resins used for forming an insulating layer of a printed wiring board can be used, and among them, an epoxy resin is preferable. Thus, in one embodiment, the first resin composition comprises (a) an epoxy resin and (b) a curing agent. The first resin composition may further contain additives such as (c) an inorganic filler, (d) a thermoplastic resin, (e) a curing accelerator, (f) a flame retardant and (g) rubber particles.

Hereinafter, an epoxy resin, a curing agent, and an additive which can be used as the material of the first resin composition will be described.

- (a) Epoxy resin-

Examples of the epoxy resin include epoxy resins such as 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, 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 novolak type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spirocyclic epoxy resins, cyclohexanedimethanol type epoxy resins, A tylene ether type epoxy resin and a trimethylol type epoxy resin. The epoxy resin may be used singly or in combination of two or more kinds.

The epoxy resin preferably contains an epoxy resin having two or more epoxy groups in one molecule. When the nonvolatile component of the epoxy resin is 100% by mass, it is preferable that at least 50% by mass or more of the epoxy resin is an epoxy resin having two or more epoxy groups in one molecule. Among them, an epoxy resin (hereinafter referred to as &quot; liquid epoxy resin &quot;) having two or more epoxy groups in one molecule at a temperature of 20 ° C and an epoxy resin having three or more epoxy groups in one molecule, (Hereinafter referred to as &quot; solid epoxy resin &quot;). By using a liquid epoxy resin and a solid epoxy resin as an epoxy resin in combination, a resin composition having excellent flexibility can be obtained. Further, the fracture strength of the insulating layer formed by curing the resin composition is also improved.

As the liquid epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin and naphthalene type epoxy resin are preferable, and bisphenol A type epoxy resin, bisphenol F type epoxy resin and naphthalene type epoxy resin More preferably a bisphenol A type epoxy resin or a bisphenol F type epoxy resin. Specific examples of the liquid epoxy resin include "HP4032", "HP4032D", "HP4032SS" (naphthalene type epoxy resin), "jER828EL" (bisphenol A type epoxy resin) manufactured by Mitsubishi Kagaku Co., "JER807" (bisphenol F type epoxy resin), "jER152" (phenol novolak type epoxy resin), "ZX1059" (manufactured by Shinnitetsu Sumikin Kagaku Co., EX-721 &quot; (glycidyl ester type epoxy resin) manufactured by Nagase Chemical Industries, Ltd., and the like. These may be used singly or in combination of two or more.

Examples of the solid epoxy resin include naphthalene type tetrafunctional epoxy resin, cresol novolak type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol novolak type epoxy resin, biphenyl type epoxy resin, or naphthylene ether Type epoxy resin, a naphthalene-type tetra-functional epoxy resin, a biphenyl-type epoxy resin, and a naphthylene ether-type epoxy resin are more preferable, and a naphthalene type tetra-functional epoxy resin and a biphenyl-type epoxy resin are more preferable. Specific examples of the solid epoxy resin include "HP-4700", "HP-4710" (naphthalene type tetrafunctional epoxy resin), "N-690" (cresol novolak type epoxy resin) EXA7311-G3 "," EXA7311-G4 "," EXA7311-G4S "," HP6000 "(dicyclopentadiene type epoxy resin) (Naphthylene ether type epoxy resin), "EPPN-502H" (trisphenol type epoxy resin), "NC7000L" (naphthol novolac epoxy resin), "NC3000H", "NC3000" "ESN475" (naphthol novolak type epoxy resin), "ESN485V" (naphthol novolak type epoxy resin), "NC3000L", "NC3100" (biphenyl type epoxy resin), "Shinnit Tetsu Sumikin Kagaku" "YX4000H", "YL6121" (biphenyl type epoxy resin), "YX4000HK" (biquileneol type epoxy resin) manufactured by Mitsubishi Chemical Corporation, Karu, Ltd., and the like, "PG-100", "CG-500", manufactured by Mitsubishi Kagaku, "YL7800" manufactured by the manufacturing or wrong (fluorene-type epoxy resin) of the preparation.

When a liquid epoxy resin and a solid epoxy resin are used in combination as the epoxy resin, the proportion thereof (liquid epoxy resin: solid epoxy resin) is preferably in the range of 1: 0.1 to 1: 5 by mass ratio. By setting the proportions of the liquid epoxy resin and the solid epoxy resin in this range, it is possible to obtain appropriate adhesiveness when i) used in the form of a resin sheet, and ii) to obtain sufficient flexibility when used in the form of a resin sheet And (iii) an insulating layer having sufficient breaking strength can be obtained. The ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) in the mass ratio is more preferably in the range of 1: 0.3 to 1: 4.5, more preferably in the range of 1: : 0.6 to 1: 4, and particularly preferably 1: 0.8 to 1: 4.

The content of the epoxy resin in the first resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, or 30% by mass or more. The upper limit of the content of the epoxy resin is not particularly limited, but preferably 99 mass% or less, more preferably 95 mass% or less, still more preferably 90 mass% or less, 85 mass% or less, 80 mass% or less, 75 Or less or 70 mass% or less.

 In the present invention, the content of each component constituting the resin composition is a value obtained when the total amount of the non-volatile components in the resin composition is 100% by mass.

The epoxy equivalent of the epoxy resin is preferably 50 to 3000, more preferably 80 to 2000, still more preferably 110 to 1000. With this range, the crosslinking density of the cured product becomes sufficient, and an insulating layer with a low surface roughness can be formed. The epoxy equivalent can be measured in accordance with JIS K7236, and is the mass of the resin containing one equivalent of an epoxy group.

The weight average molecular weight of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and still more preferably 400 to 1500. Here, the weight average molecular weight of the epoxy resin is a weight average molecular weight in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

- (b) Hardener -

The curing agent is not particularly limited as far as it has a function of curing an epoxy resin, and examples thereof include phenol-based curing agents, naphthol-based curing agents, active ester-based curing agents, benzoxazine based curing agents and cyanate ester-based curing agents. The curing agent may be used singly or in combination of two or more kinds.

As the phenol-based curing agent and naphthol-based curing agent, a phenol-based curing agent having a novolak structure or a naphthol-based curing agent having a novolak structure is preferable from the viewpoints of heat resistance and water resistance. From the viewpoint of adhesion with the conductor layer, a nitrogen-containing phenol-based curing agent is preferable, and a phenazine-based curing agent containing a triazine skeleton is more preferable. Among them, a phenazine novolac resin containing a triazine skeleton is preferable from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion (peel strength) with a conductor layer.

Specific examples of the phenol-based curing agent and naphthol-based curing agent include "MEH-7700", "MEH-7810", "MEH-7851" manufactured by Meiwa Kasei Co., SN175 "," SN190 "," SN475 "," SN485 "," SN495 "," SN375 "," SN395 ", and" SN395 "manufactured by Tohto Kasei Co., LA7052 &quot;, &quot; LA7054 &quot;, and &quot; LA3018 &quot; manufactured by DIC Corporation.

From the viewpoint of obtaining an insulating layer having a small surface roughness after the roughening treatment, an active ester-based curing agent is also preferable. The active ester-based curing agent is not particularly limited, but generally includes ester groups having high reactivity, such as esters of phenol esters, thiophenol esters, N-hydroxyamine esters, and heterocyclic hydroxy compounds, Are preferably used. It is preferable that the active ester-based curing agent is obtained by a condensation reaction of a carboxylic acid compound and / or a thiocarboxylic acid compound with a hydroxy compound and / or a thiol compound. From the viewpoint of heat resistance improvement, an active ester type curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester type curing agent obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound is more preferable. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid and pyromellitic acid. Examples of the phenol compound or naphthol compound include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o- Cresol, catechol, alpha -naphthol, beta -naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, Trihydroxybenzophenone, tetrahydroxybenzophenone, fluoroglucine, benzene triol, dicyclopentadiene type diphenol compounds, phenol novolak, and the like. Here, the "dicyclopentadiene type diphenol compound" refers to a diphenol compound obtained by condensing two molecules of phenol in one dicyclopentadiene molecule.

Specifically, there can be mentioned 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 phenol novolac, a benzoyl compound of phenol novolac Active ester compounds are preferable, and among them, active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadiene type diphenol structure are more preferable. The "dicyclopentadiene type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentaleene-phenyl.

EXB9451 "," EXB9460 "," EXB9460S "," HPC-8000-65T "(manufactured by DIC Corporation) as the active ester compound containing a dicyclopentadiene type diphenol structure as a commercially available product of the active ester type curing agent, , EXB9416-70BK (manufactured by DIC Corporation) as an active ester compound containing a naphthalene structure, DC808 (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing an acetylated product of phenol novolak, phenol And YLH1026 (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing a benzoylated novolak.

Specific examples of the benzoxazine type curing agent include "HFB2006M" manufactured by Showa Kobunshi Co., Ltd., "P-d" and "F-a" manufactured by Shikoku Seiko Kogyo Co.,

Examples of the cyanate ester curing agent include bisphenol A dicyanate, polyphenol cyanate, oligo (3-methylene-1,5-phenylene cyanate), 4,4'- Dimethylphenyl cyanate), 4,4'-ethylidenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1- Cyanate phenylmethane), bis (4-cyanate-3,5-dimethylphenyl) methane, 1,3-bis Bifunctional cyanate resins derived from phenolic novolacs and cresol novolacs such as bis (4-cyanophenyl) thioether and bis (4-cyanate phenyl) ether, and polyfunctional cyanate resins derived from these cyanate resins, And prepolymers. Specific examples of the cyanate ester-based curing agent include "PT30" and "PT60" (both phenol novolak-type multifunctional cyanate ester resins) manufactured by RONJANJANPAN CO., LTD., "BA230" (part or all of bisphenol A dicyanate And a prepolymer obtained by trimerization to give a trimer).

The ratio of the epoxy resin to the curing agent is preferably in the range of 1: 0.2 to 1: 2, more preferably in the range of 1: 0.3 to 1: 1.5, in the ratio of [the total number of epoxy groups of the epoxy resin] , More preferably from 1: 0.4 to 1: 1.2. 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 kind of the curing agent. The total number of epoxy groups in the epoxy resin refers to a value obtained by dividing the solid component mass of each epoxy resin by the epoxy equivalent in terms of the total epoxy resin and the total number of reactors in the curing agent means that the solid mass of each curing agent is equivalent to the reactor Divided by the total amount of the curing agent. By setting the ratio of 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 the epoxy resin (a) and the curing agent (b) described above. The first resin composition preferably comprises (a) a mixture of a liquid epoxy resin and a solid epoxy resin (the mass ratio of the liquid epoxy resin to the solid epoxy resin is preferably from 1: 0.1 to 1: 5, more preferably from 1: 0.3 to 1 : 4.5, more preferably in the range of 1: 0.6 to 1: 4, and still more preferably in the range of 1: 0.8 to 1: 4), (b) a phenolic curing agent as a curing agent, (Preferably at least one selected from the group consisting of a phenol-based curing agent, a naphthol-based curing agent and an active ester-based curing agent) selected from the group consisting of a curing agent, an active ester curing agent and a cyanate ester- Respectively.

- (c) inorganic filler -

The first resin composition may further contain an inorganic filler. Examples of inorganic fillers include inorganic fillers such as silica, alumina, glass, cordierite, silicon oxide, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, Boron, aluminum nitride, manganese nitride, aluminum borate, strontium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate, zirconium phosphate and zirconium tungstate . Of these, silica such as amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica and the like is particularly suitable. As the silica, spherical silica is preferable. The inorganic fillers may be used singly or in combination of two or more kinds.

The average particle diameter of the inorganic filler used in the first resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 500 nm or less, more preferably 300 nm or less More preferably not more than 150 nm, not more than 100 nm, not more than 90 nm, not more than 80 nm, not more than 70 nm, not more than 60 nm, or not more than 50 nm. The lower limit of the average particle diameter is not particularly limited, but is usually 5 nm or more. Examples of commercially available inorganic fillers having such an average particle diameter include "YC100C", "YA050C", "YA050C-MJE", "YA010C" manufactured by Adomex Corporation, "YA010C" manufactured by Denki Kagakukogyo Co., UF30 "manufactured by Tokuyama," NF-3N "," NF-4N "and" NF-5N ". The average particle diameter of the inorganic filler can be measured by a laser diffraction / scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be measured by using a laser diffraction scattering particle size distribution measuring apparatus, and the median diameter of the inorganic filler is determined as the average particle diameter. The measurement sample can be preferably those in which an inorganic filler is dispersed in water by ultrasonic waves. As the laser diffraction scattering type particle size distribution measuring apparatus, LA-500 manufactured by Horiba Seisakusho Co., Ltd. and the like can be used.

From the viewpoint of improving moisture resistance and dispersibility, the inorganic filler is preferably selected from the group consisting of an amino silane coupling agent, an epoxy silane coupling agent, a mercapto silane coupling agent, a silane coupling agent, an organosilazane compound, a titanate coupling agent, Of at least one surface treating agent. As commercially available products of surface treatment agents, for example, "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-mercapto KBE903 "(3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd.," KBM573 "(manufactured by Shin-Etsu Chemical Co., Methoxysilane), "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd., and the like.

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 at least 0.02 mg / m 2, more preferably at least 0.1 mg / m 2, and most preferably at least 0.2 mg / m 2 from the viewpoint of improving the dispersibility of the inorganic filler. On the other hand, it is preferably 1 mg / m 2 or less, more preferably 0.8 mg / m 2 or less, still more preferably 0.5 mg / m 2 or less from the viewpoint of preventing the melt viscosity of the resin varnish and the increase of the melt viscosity in the sheet form .

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 (for example, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler surface-treated with a surface treatment agent and ultrasonically cleaned at 25 占 폚 for 5 minutes. After the supernatant is removed and the solid content is dried, the amount of carbon per unit surface area of the inorganic filler can be measured using a carbon analyzer. As the carbon analyzer, "EMIA-320V" manufactured by Horiba Seisakusho Co., Ltd. and the like can be used.

The content of the inorganic filler in the first resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 40 mass% or less, more preferably 30 mass% or less, , Preferably not more than 25 mass%, more preferably not more than 20 mass%, not more than 18 mass%, not more than 16 mass%, not more than 14 mass%, not more than 12 mass%, not more than 10 mass%, not more than 8 mass%, not more than 6 mass% , 4 mass% or less, or 2 mass% or less. The lower limit of the content of the inorganic filler in the first resin composition is not particularly limited and may be 0% by mass.

- (d) Thermoplastic resin -

The first resin composition may further include a thermoplastic resin. Examples of the thermoplastic resin include thermoplastic resins such as phenoxy resin, polyvinyl acetal resin, acrylic resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyether sulfone resin, polyphenylene ether resin and polysulfone resin And the like. The thermoplastic resin may be used singly or in combination of two or more.

The weight average molecular weight of the thermoplastic resin in terms of polystyrene is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and still more preferably in the range of 20,000 to 60,000. The weight average molecular weight of the thermoplastic resin in terms of polystyrene is measured by gel permeation chromatography (GPC). Specifically, the weight average molecular weight of the thermoplastic resin in terms of polystyrene was measured using LC-9A / RID-6A manufactured by Shimadzu Corporation, Shodex K-800P / K- 804L / K-804L can be measured using a calibration curve of standard polystyrene at a column temperature of 40 ° C using chloroform as the mobile phase.

Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, novolak skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, A phenoxy resin having at least one skeleton selected from the group consisting of a skeleton, an anthracene skeleton, an adamantane skeleton, a terpene skeleton, and a trimethyl cyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. The phenoxy resin may be used singly or in combination of two or more. Specific examples of the phenoxy resin include "1256" and "4250" (both phenol resins containing a bisphenol A skeleton), "YX8100" (phenoxy resin containing a bisphenol S skeleton), and "YX6954" (Phenoxy resin containing bisphenol acetophenone skeleton), "FX280" and "FX293" manufactured by Toto Kasei Co., Ltd., "YX7553", "YL6794", "YL7213" manufactured by Mitsubishi Chemical Corporation , &Quot; YL7290 &quot;, and &quot; YL7482 &quot;.

The acrylic resin is preferably a functional group-containing acrylic resin, more preferably an epoxy group-containing acrylic resin, and more preferably an epoxy group-containing acrylic ester copolymer resin. When a functional group-containing acrylic resin is used as the acrylic resin, the functional group equivalent thereof is preferably 1000 to 50000, and more preferably 2500 to 30000.

Specific examples of the acrylic resin include "SG-80H" and "SG-P3" (epoxy group-containing acrylic ester copolymer resin) manufactured by Nagase ChemteX Corporation.

As specific examples of the polyvinyl acetal resin, there may be mentioned telephotical 4000-2, 5000-A, 6000-C, 6000-EP manufactured by Denki Kagaku Kogyo Co., Ltd., Sreek BH series (manufactured by Sekisui Chemical Co., , BX series, KS series, BL series, BM series and the like.

Specific examples of the polyimide resin include "Rika coat SN20" and "Rika coat PN20" manufactured by Shin-Epson Lion Corporation. Specific examples of the polyimide resin include linear polyimide obtained by reacting a bifunctional hydroxyl-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (JP-A-2006-37083), a polysiloxane skeleton- (Japanese Unexamined Patent Application Publication No. 2002-12667 and Japanese Unexamined Patent Publication No. 2000-319386, etc.).

Specific examples of the polyamide-imide resin include "Bioromax HR11NN" and "Bioromax HR16NN" manufactured by Toyoboseki KK. Specific examples of the polyamideimide resin include modified polyamideimides such as polyamideimide containing polysiloxane skeleton "KS9100" and "KS9300" manufactured by Hitachi Chemical Co., Ltd.

Specific examples of the polyethersulfone resin include "PES 5003P" manufactured by Tsumito Tomokagaku Co., Ltd. and the like.

Specific examples of the polysulfone resin include polysulfone &quot; P1700 &quot; and &quot; P3500 &quot; manufactured by Spherical Silica Advanosporimemas.

The content of the thermoplastic resin in the first resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 0.1% by mass or more, more preferably 1% by mass or more, Is not less than 3 mass%, not less than 5 mass%, or not less than 7 mass%. The upper limit of the content of the thermoplastic resin is not particularly limited, but is preferably 50 mass% or less, more preferably 40 mass% or less, further preferably 30 mass% or less.

- (e) Curing accelerator -

The first resin composition may further include a curing accelerator. Examples of the curing accelerator include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, and guanidine-based curing accelerators. Phosphorus hardening accelerators, amine hardening accelerators and imidazole hardening accelerators are preferable , An amine-based curing accelerator, and an imidazole-based curing accelerator are more preferable. The curing accelerator may be used singly or in combination of two or more kinds.

Examples of phosphorus hardening accelerators include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl) triphenyl Phosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and the like, and triphenylphosphine and tetrabutylphosphonium decanoate are preferable.

Examples of the amine-based curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) -Diazabicyclo (5,4,0) undecene, and 4-dimethylaminopyridine and 1,8-diazabicyclo (5,4,0) -undecene are preferred.

Examples of the imidazole-based curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, Imidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl- Benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl- 4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl- Trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')] -ethyl-s-triazine, 2,4- diamino-6- [ Imidazolyl- (1 ')] - ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- Triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')] - ethyl- Water, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, 2-phenylimidazoline, And imidazole compounds such as imidazole compounds and epoxy resins. Preferred are 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole.

Examples of the guanidine curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1- (o-tolyl) guanidine, dimethylguanidine, , Trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo [4.4.0] deca-5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, 1- (o-tolyl) biguanide, and the like, and dicyandiamide, 1,5,7-triazabicyclo [4.4.0] deca-5-ene are preferred.

The content of the curing accelerator in the first resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained. When the total amount of the non-volatile components in the epoxy resin and the curing agent is 100 mass% By mass to 3% by mass.

- (f) Flame retardant -

The first resin composition may further contain a flame retardant. Examples of the flame retardant include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicon-based flame retardants, metal hydroxides and the like. The flame retardant may be used alone, or two or more flame retardants may be used in combination. The content of the flame retardant in the first resin composition layer is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but it is preferably 0.5% by mass to 20% by mass, more preferably 1% by mass to 15% And more preferably 1.5% by mass to 10% by mass.

- (g) Rubber particles -

The first resin composition may further comprise rubber particles. As the rubber particles, those which do not dissolve in an organic solvent used for preparing a resin varnish described below and which are not compatible with the above-mentioned epoxy resin, curing agent, thermoplastic resin and the like are used. Generally, such rubber particles are prepared by increasing the molecular weight of the rubber component to a level that does not dissolve in an organic solvent or resin so as to have a particle shape.

Examples of the rubber particles include core-shell type rubber particles, crosslinked acrylonitrile-butadiene rubber particles, crosslinked styrene-butadiene rubber particles, acrylic rubber particles and the like. The core-shell-type rubber particle is a rubber particle having a core layer and a shell layer, for example, a two-layer structure in which the shell layer of the outer layer is composed of a glassy polymer and the core layer of the inner layer is composed of a rubber- A three-layer structure composed of a glassy polymer, an intermediate layer made of a rubbery polymer and a core layer made of a glassy polymer, and the like. The glassy polymer layer is composed of, for example, a methyl methacrylate polymer or the like, and the rubbery polymer layer is composed of, for example, a butyl acrylate polymer (butyl rubber). The rubber particles may be used singly or in combination of two or more kinds.

The average particle diameter of the rubber particles is preferably in the range of 0.005 탆 to 1 탆, and more preferably in the range of 0.2 탆 to 0.6 탆. The average particle diameter of the rubber particles can be measured using a dynamic light scattering method. For example, rubber particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves or the like, and the particle size distribution of the rubber particles is prepared on the basis of mass by using a dense particle size analyzer (FPAR-1000, manufactured by Otsuka Denshi Co., Ltd.) , And measuring the median diameter thereof as the average particle diameter. The content of the rubber particles in the first resin composition is preferably 1% by mass to 20% by mass, more preferably 2% by mass to 10% by mass, and still more preferably 2% by mass to 5% by mass.

- Other ingredients -

The first resin composition may contain other additives as needed. Examples of the other additives include organic metal compounds such as organic copper compounds, organic zinc compounds and organic cobalt compounds, organic fillers such as organic fillers, thickeners, Defoaming agents, leveling agents, adhesion-imparting agents, and resin additives such as coloring agents.

&Lt; Second Resin Composition >

The second resin composition is used to form a remaining region (bulk portion) of the resin composition layer excluding a region near the bonding surface with the support.

The second resin composition determines the bulk characteristics of the resin composition layer, and furthermore, the bulk characteristics of the insulating layer. The second resin composition contains a high content of an inorganic filler from the viewpoints of lowering the coefficient of thermal expansion of the obtained insulating layer and preventing occurrence of cracks and circuit deformation due to a difference in thermal expansion between the insulating layer and the conductor layer.

The content of the inorganic filler in the second resin composition is preferably 50% by mass or more, more preferably 52% by mass or more, still more preferably 54% by mass or more, and still more preferably 50% by mass or more, from the viewpoint of lowering the thermal expansion coefficient of the obtained insulating layer At least 56 mass%, more preferably at least 58 mass%, at least 60 mass%, at least 62 mass%, at least 64 mass%, at least 66 mass%, at least 68 mass%, or at least 70 mass%. The upper limit of the content of the inorganic filler in the second resin composition is preferably 96% by mass or less, more preferably 95% by mass or less, further preferably 90% by mass or less from the viewpoint of the mechanical strength of the obtained insulating layer, 85% by mass or less.

Examples of the inorganic filler include inorganic fillers described for the first resin composition, among which silica is preferable, and spherical silica is more preferable. The average particle diameter of the inorganic filler contained in the second resin composition is preferably in the range of 0.01 탆 to 5 탆, more preferably in the range of 0.05 탆 to 2 탆 from the viewpoint of realizing sufficient circuit filling property by increasing the fluidity of the resin composition layer More preferably in the range of 0.1 탆 to 1 탆, and even more preferably in the range of 0.2 탆 to 0.8 탆. Examples of commercially available inorganic fillers having such an average particle diameter include "SOC2" and "SOC1" manufactured by Adomex Corporation.

The inorganic filler contained in the second resin composition is preferably treated with a surface treating agent. The kind of the surface treating agent and the degree of the surface treatment are the same as described in the <first resin composition>.

Examples of other materials included in the second resin composition include (a) a curable resin including an epoxy resin, and (b) a curing agent described in the <first resin composition>. Thus, in one embodiment, the second resin composition comprises (a) an epoxy resin, (b) a curing agent, and (c) an inorganic filler. A suitable example of each component is as described in &quot; First Resin Composition &quot;, but among them, the second resin composition is a mixture of (a) a mixture of a liquid epoxy resin and a solid epoxy resin as an epoxy resin (liquid epoxy resin: The mass ratio is preferably in the range of 1: 0.1 to 1: 5, more preferably in the range of 1: 0.3 to 1: 4.5, further preferably in the range of 1: 0.6 to 1: 4, (B) at least one kind selected from the group consisting of a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent and a cyanate ester-based curing agent as the curing agent (preferably a phenolic curing agent, A curing agent, and an active ester curing agent), and (c) silica as an inorganic filler.

The content of the epoxy resin (a) in the second resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 3% by mass to 50% by mass, more preferably 5% % To 45% by mass, more preferably 5% by mass to 40% by mass, still more preferably 7% by mass to 35% by mass.

The amount ratio of the epoxy resin (a) and the curing agent (b) in the second resin composition may be the same as that described in the <first resin composition>.

The second resin composition may further comprise at least one component selected from the group consisting of (d) a thermoplastic resin, (e) a curing accelerator, (f) a flame retardant and (g) rubber particles. Suitable examples of the components (d) to (g) are as described in &quot; First Resin Composition &quot;. The content of the thermoplastic resin (d) in the second resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 0.1% by mass to 20% by mass, more preferably 0.5% To 10% by mass. The content of the curing accelerator (e) in the second resin composition is preferably 0.05% by mass to 3% by mass based on 100% by mass of the total amount of the nonvolatile component of the epoxy resin (a) and the curing agent (b). The content of the flame retardant (f) in the second resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 0.5% by mass to 10% by mass, more preferably 1% To 9% by mass, and more preferably from 1.5% by mass to 8% by mass. The content of the rubber particles (g) in the second resin composition is not particularly limited as long as a resin composition layer having a desired composition gradient can be obtained, but is preferably 1% by mass to 10% by mass, more preferably 2% % To 5% by mass.

The second resin composition may contain other additives as required. Examples of such other additives include organic metal compounds such as organic copper compounds, organic zinc compounds and organic cobalt compounds, organic fillers such as organic fillers, thickeners, Defoaming agents, leveling agents, adhesion-imparting agents, and resin additives such as coloring agents.

Hereinafter, the present invention will be described in detail based on its preferred embodiments.

[Resin sheet with support]

A resin sheet with a support according to the present invention comprises a support and a resin composition layer bonded to the support, wherein the resin composition layer has an inorganic filler content of 50 mass% or more, wherein the resin composition layer contains, in a region near the surface of the support, (That is, a gradient of an amount of a positive value or more toward the thickness direction from the bonding surface with the support) to the ratio of the amount of the resin component (inorganic filler / resin component).

In the resin composition layer included in the resin sheet with a support of the present invention, a resin component is present in a rich phase on the bonding surface with the support, but at a certain distance from the bonding surface to the support in the thickness direction, . Here, the &quot; thickness direction &quot; refers to the thickness direction of the resin composition layer and indicates the direction perpendicular to the surface of the resin composition layer. The proportion of the inorganic filler in the resin composition layer is preferably from 0.05 to 2 mu m, more preferably from 0.05 to 1.5 mu m, further preferably from 0.05 to 1.5 mu m in the thickness direction from the bonding surface with the support Particularly at a distance of 0.05 占 퐉 to 1 占 퐉, particularly preferably at a distance of 0.05 占 퐉 to 0.5 占 퐉.

Further, if it goes further in the thickness direction, there is no gradient in the ratio between the inorganic filler and the resin component, resulting in an image having a uniform composition. According to the resin sheet with a support of the present invention comprising a resin composition layer having an abrupt gradient in composition only in a limited region near the surface of the support side, since the homogeneous composition is maintained as a bulk property, the resin sheet has excellent strength and heat resistance, After the roughening treatment, the insulating layer exhibiting excellent peel strength against the conductor layer can be formed. As will be described later in detail, it has been confirmed that the insulating layer formed by using the resin sheet with the support of the present invention exhibits excellent peel strength with respect to the conductor layer even though the surface roughness after the roughening treatment is small. The adhered resin sheet significantly contributes to the fine wiring of the printed wiring board.

In the present invention, when the ratio of the inorganic filler to the resin component in the vicinity of the surface of the resin composition layer in the vicinity of the surface of the support composition is expressed, the ratio of the ratio of the inorganic filler to the resin component in the cross section of the resin composition layer in the direction perpendicular to the surface of the support A predetermined distance d3 (占 퐉) from the resin area A _{d1 - d2} of the region from the boundary of the layer from the predetermined distance d1 (占 퐉) to the predetermined distance d2 (占 퐉) a resin area _d2 of the area to _the ratio of _d3 and the (kA _{d1 - - d2} / _{d3 d2} a) is assumed to be used. Here, d1, d2 and d3 are numbers satisfying 0? D1 <d2 <d3, and k is a coefficient satisfying k = | d2-d3 | / | d1-d2 |.

The resin area ratio was observed by SEM on the cross section of the resin composition layer 20 in a direction perpendicular to the surface of the support 10 (Z direction in Fig. 1) as schematically shown in Fig. 1, ( _{D1 - d2} ) of the region 21a where the distance from the boundary (the position of Z = 0 in Fig. 1) between the resin composition layer 10 and the resin composition layer 20 is from d1 (mu m) to d2 The resin area A _{d2 - d3} of the region 21b whose distance from the boundary is from d2 (mu m) to d3 (mu m) can be measured and calculated from the obtained A _{d1 - d2} value and A _{d2 - d3} value . In measuring the values of A _{d1 - d2} and A _{d2 - d3} , the width of the measurement region (measurement distance in the direction parallel to the surface of the support) is set to be the same.

In the present invention, the &quot; resin area &quot; refers to the area occupied by the resin component. The term &quot; resin component &quot; as to the resin area means a component excluding the inorganic filler among components constituting the resin composition.

In the resin sheet with the support of the present invention, the resin composition layer has a sharp gradient in the ratio of the inorganic filler to the resin component in the region near the surface on the support side, and the ratio kAd1 _-d2 / _Ad2-d3 is d1, d2 And the value of d3.

That is, in the resin sheet with a support of the present invention, in the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 1 탆 A _0-1 and a resin area A _1-2 in a region where the distance from the boundary is from 1 탆 to 2 탆 satisfy the relationship of A _0-1 / A _1-2 > 1.1. From the viewpoint of obtaining an insulating layer exhibiting excellent peel strength with respect to the conductor layer after the roughening treatment while maintaining the bulk characteristic that the content of the inorganic filler is high, the resin sheet with the support of the present invention preferably has A _0-1 / A _1-2 ? 1.15, more preferably A _0-1 / A _1-2 ? 1.2.

The upper limit of the A _0-1 / A _{1- 2} ratio is not particularly limited, but is usually 20 or less, preferably 15 or less, more preferably 10 or less, further preferably 5 or less.

In this case, the (resin area) / (total area) ratio in a region where the distance from the boundary between the support and the resin composition layer is 0 mu m to 1 mu m in the cross section of the resin composition layer in the direction perpendicular to the surface of the support Preferably 0.3 or more, more preferably 0.4 or more, still more preferably 0.5 or more, still more preferably 0.6 or more, 0.7 or more, 0.8 or more or 0.9 or more. The upper limit of the ratio of (resin area) / (total area) is not particularly limited and may be 1.

The uniform composition and the high content of the inorganic filler in the resin sheet with the support of the present invention are such that the insulating layer exhibiting excellent peel strength against the conductor layer after the roughening treatment while maintaining the bulk characteristics The resin area A _0-0.5 in the region where the distance from the boundary between the support and the resin composition layer is from 0 탆 to 0.5 탆 and the distance from the boundary is 0.5 탆 to 1 Mu m or less, the resin area A _0.5-1 in the region where the ratio of A to B is in the range of A _0-0.5 / A _0.5-1 > 1.1 is preferably satisfied. From the viewpoint of realizing an insulating layer exhibiting a higher peel strength with respect to the conductor layer after the roughening treatment, the resin sheet with a support of the present invention more preferably has an A _0-0.5 / A _0.5-1 ? 1.2, A _0-0.5 / A _0.5-1 ? 1.22, still more preferably A _0-0.5 / A _0.5-1 ? 1.24, particularly preferably A _0-0.5 / A _0.5-1 ? 1.26, A _0-0.5 / A _0.5-1 ? 1.28, A _0-0.5 / A _0.5-1 ? 1.3, or A _0-0.5 / A _0.5-1 ? 1.32.

The upper limit of the A _0-0.5 / A _0.5-1 ratio is not particularly limited, but is usually 20 or less, preferably 15 or less, more preferably 10 or less, further preferably 5 or less.

In this case, the (resin area) / (total area) ratio in a region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 0.5 탆 in the cross section of the resin composition layer in the direction perpendicular to the surface of the support Preferably at least 0.5, more preferably at least 0.6, even more preferably at least 0.7, even more preferably at least 0.8 or at least 0.9. The upper limit of the ratio of (resin area) / (total area) is not particularly limited and may be 1.

As described above, in the resin sheet with a support according to the present invention, the resin composition layer has a composition gradient only in a limited region near the surface on the side of the support, and maintains a uniform composition in bulk characteristics.

In a preferred embodiment, the resin sheet with a support according to the present invention has a region in which the distance from the boundary between the support and the resin composition layer is from 2 탆 to d 탆 in the cross section of the resin composition layer in the direction perpendicular to the surface of the support And the resin area A _{d -0.5D} in the region where the distance from the boundary is from _d占 퐉 to 0.5 占 퐉 is 0.9? KA2 _-d / Ad _-0.5D ? 1.1 (Where k is a coefficient satisfying k = d-0.5D / 2-d, d is a number satisfying 2 <d <0.5D, and D is a thickness of the resin composition layer) Is satisfied. This indicates that the resin composition layer contained in the resin sheet with the support of the present invention has a uniform composition in a region where the distance from the surface of the support is 2 mu m or more.

In a more preferred embodiment, the resin sheet with a support of the present invention has a cross section of the resin composition layer in the direction perpendicular to the surface of the support, wherein the distance from the boundary between the support and the resin composition layer is from 1.5 m to d resin, the area of the area _{a-1.5 d} and, in the area of resin-in area, the distance from the boundary to from d㎛ 0.5D㎛ a _d is _{-0.5D, 0.9 ≤ kA 1 .5-d} / a d -0.5 _D ? 1.1 where k is a coefficient satisfying k = d-0.5D / 1.5-d, d is a number satisfying 1.5 <d <0.5D, and D is a thickness of the resin composition layer ). &Lt; / RTI &gt; This indicates that the resin composition layer included in the resin sheet with a support of the present invention has a uniform composition in a region where the distance from the surface of the support is 1.5 mu m or more.

In a more preferred embodiment, the resin sheet with a support according to the present invention is such that the distance from the boundary between the support and the resin composition layer in the cross section of the resin composition layer in the direction perpendicular to the surface of the support is from 1 mu m to d mu m and a resin area a _1-d in the region, the distance from the boundary area a _{d -0.5D} resin in the area from d㎛ to 0.5D㎛, ≤ 0.9 kA _{l -d} / a ≤ _{d -0.5D} 1.1 wherein k is a coefficient satisfying k = d-0.5D / 1-d, d is a number satisfying 1 <d <0.5D, and D is a thickness of the resin composition layer The relationship is satisfied. This indicates that the resin composition layer included in the resin sheet with a support of the present invention has a uniform composition in a region having a distance of 1 mu m or more from the surface of the support.

In a particularly preferred embodiment, the resin sheet with a support of the present invention has a cross section of the resin composition layer in a direction perpendicular to the surface of the support, wherein the distance from the boundary between the support and the resin composition layer is from 0.5 m to d resin, the area of the area _{a-0.5 d} and, in the area of resin-in area, the distance from the boundary to from d㎛ 0.5D㎛ a _d is _{-0.5D, 0.9 ≤ kA 0 .5-d} / a d -0.5 _D ? 1.1 where k is a coefficient satisfying k = d-0.5D /0.5-d, d is a number satisfying 0.5 <d <0.5D, and D is a thickness of the resin composition layer ). &Lt; / RTI &gt; This indicates that the resin composition layer included in the resin sheet with a support of the present invention has a uniform composition in a region where the distance from the surface of the support is 0.5 mu m or more. In the above resin area ratio, and the denominator A is not necessarily _{d -0.5D,} A may be a _{-D d} (i.e., the distance from the boundary area of the resin in the region to D㎛ from d㎛). Even when the denominator is set to A _{d -D} instead of A _{d -0.5 D} , the value is corrected by the coefficient k, so that a suitable range of the resin area ratio is the same as described above.

In the resin sheet with a support of the present invention, the content of the inorganic filler in the resin composition layer is 50 mass% or more. The content of the inorganic filler in the resin composition layer is preferably 55% by mass or more, more preferably 60% by mass or more, still more preferably 65% by mass or more from the viewpoint of sufficiently lowering the coefficient of thermal expansion of the resulting insulating layer .

In the present invention, the content of each component in the resin composition layer is a value obtained when the total amount of the non-volatile component in the resin composition layer is 100 mass%. For example, the content of the inorganic filler in the resin composition layer may be set so that the content of the inorganic filler in the first resin composition and the content of the inorganic filler in the second resin composition described above, And the amount of the second resin composition.

In the resin sheet with the support of the present invention, in which the ratio (A _0-1 / A _1-2 ) of the resin area A _0-1 to the resin area A _1-2 is in the above specific range, the deterioration The content of the inorganic filler in the resin composition layer can be further increased. For example, the content of the inorganic filler in the resin composition layer may range from 66 mass% or more, 68 mass% or more, 70 mass% or more, 72 mass% or more, 74 mass% or more, 76 mass% or more, or 78 mass% or more You can raise it.

The upper limit of the content of the inorganic filler in the resin composition layer is preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less, from the viewpoint of the mechanical strength of the obtained insulating layer.

Details of each component of the resin composition layer including the inorganic filler are as described in <First Resin Composition> and <Second Resin Composition>. In one embodiment, the resin composition layer included in the resin sheet with a support of the present invention includes an inorganic filler, a curable resin, and a curing agent. The resin composition layer may further contain at least one additive selected from the group consisting of a thermoplastic resin, a curing accelerator, a flame retardant and a rubber particle, and may further contain at least one additive selected from the group consisting of an organic metal compound, an organic filler, a thickener, a defoaming agent, a leveling agent, And other resin additives such as colorants.

The content of the other components in the resin composition layer is not particularly limited as long as the content of the inorganic filler is within the above specific range, and may be a range usually used when forming the insulating layer of the printed wiring board. In the present invention, the resin composition layer is formed by using the first and second resin compositions described above. The bulk portion of the resin composition layer is formed substantially from the second resin composition, 1 The contribution rate of the resin composition is limited. Therefore, in the resin sheet with the support of the present invention, the appropriate content of the components other than the inorganic filler in the resin composition layer may be the same as the appropriate content of each component mentioned in the &quot; second resin composition &quot;

In the resin sheet with a support of the present invention, the thickness of the resin composition layer is preferably 3 占 퐉 or more, more preferably 5 占 퐉 or more, further preferably 7 占 퐉 or more, 8 占 퐉 or more, to be. The upper limit of the thickness of the resin composition layer is preferably 100 占 퐉 or less, more preferably 80 占 퐉 or less, further preferably 60 占 퐉 or less, 50 占 퐉 or less, 40 占 퐉 or less, 30 占 퐉 or less or 20 占 퐉 or less.

In the resin sheet with a support of the present invention, examples of the support include a film made of a plastic material, a metal foil and a release paper, and a film or a metal foil made of a plastic material is preferable.

When a film made of a plastic material is used as the support, examples of the plastic material include polyethylene terephthalate (hereinafter may be abbreviated as "PET"), polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN" (TAC), polyether sulfide (PES), polyether sulfide (PES), polyether sulfone (PES), polyether sulfone Polyether ketone, polyimide, and the like. Among them, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is particularly preferable.

In the case of using a metal foil as a support, examples of the metal foil include copper foil and aluminum foil, and copper foil is preferable. As the copper foil, a foil made of a single metal of copper may be used, or a foil made of an alloy of copper and another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) .

The surface of the support to be bonded to the resin composition layer may be subjected to a mat treatment or a corona treatment.

As the support, a support having a release layer having a release layer on the surface to be bonded to the resin composition layer may be used. As the release agent used for the release layer of the release layer-adhered support, for example, one or more release agents selected from the group consisting of an alkyd resin, a polyolefin resin, a urethane resin, and a silicone resin can be mentioned. SK-1, &quot; &quot; AL-5, &quot; and &quot; AL-5, &quot; manufactured by Lintec Corporation, which are PET films having a release layer composed mainly of an alkyd resin-based releasing agent as a main component, -7 &quot; and the like.

The thickness of the support is not particularly limited, but is preferably in the range of 5 탆 to 75 탆, more preferably in the range of 10 탆 to 60 탆. When a release layer-adhered support is used, it is preferable that the thickness of the entirety of the release layer-adhered support is in the above range.

The resin sheet with a support of the present invention may further include a protective film on the surface of the resin composition layer not bonded to the support (i.e., the surface opposite to the support). The protective film contributes to prevention of adhesion and scratches of dust on the surface of the resin composition layer. As the material of the protective film, the same material as described for the support may be used. The thickness of the protective film is not particularly limited, but is, for example, 1 m to 40 m. The resin sheet with a support can be used by peeling the protective film when producing a printed wiring board.

The resin sheet with a support of the present invention can be used for forming an insulating layer of a printed wiring board (for an insulating layer of a printed wiring board) to form an insulating layer of a metal-clad laminate (for an insulating layer of a metal laminate). In particular, in the production of a printed wiring board by a build-up method, it can be suitably used (for a build-up insulating layer of a printed wiring board) to form an insulating layer. In order to form a conductor layer by plating For a build-up insulating layer of a printed wiring board forming a layer).

[Production method of resin sheet with support]

The method for producing a resin sheet with a support according to the present invention is characterized in that a first layer of a first resin composition having a thickness of less than 2 탆 and a second layer of a second resin composition are bonded to each other, Wherein the inorganic filler content in the resin composition layer is 50% by mass or more, ii) the surface of the side of the resin composition layer originating in the first layer is bonded to the support, and iii) in a cross section of the resin composition layer in a direction perpendicular to the surface, and the resin in the area a _0-1-in area, the distance from the boundary between the substrate and the resin composition layer to from 0㎛ 1㎛, the distance from the boundary The resin area A _1-2 in the region of from 1 탆 to 2 탆 satisfies the relationship of A _0-1 / A _1-2 > 1.1.

The first resin composition and the second resin composition are as described above. In the present invention, it is preferable that a first layer of less than 2 占 퐉 thickness made of the first resin composition and a second layer of the second resin composition are bonded to each other so as to satisfy the conditions of i) to iii) A resin composition layer (also simply referred to as &quot; resin composition layer &quot;) is formed. Regarding the condition of i), the preferable range of the content of the inorganic filler in the resin composition layer is as described in the column of [resin sheet with support]. The condition of ii) above indicates that a resin-rich phase derived from the first resin composition is bonded to the support. The support is as described in the section [resin sheet with support]. In addition, the ⅲ), suitable resins area ratio with respect to the conditions of (A _0-1 / A _{1- 2} ratio, _0-0.5 A / A _{0.5- 1} ratio, kA _{2 -d} / A _{d -0.5D,} etc.) conditions Is as described in the column of [resin sheet with support].

The thickness of the first layer made of the first resin composition is preferably less than 2 mu m, preferably not more than 1.5 mu m, more preferably not more than 1 mu m, further preferably less than 1.0 mu m, from the viewpoint of achieving a desired resin area ratio, 0.8 탆 or less, 0.6 탆 or less, or 0.5 탆 or less. The lower limit of the thickness of the first layer is not particularly limited, but from the viewpoints of obtaining an insulating layer exhibiting excellent peel strength to the conductor layer after the roughening treatment and easy production of the resin sheet with a support, Or more.

The thickness of the second layer made of the second resin composition is not particularly limited, and the thickness of the obtained resin composition layer may be determined in a desired range while taking the thickness of the first layer into consideration. Since the second layer is a layer constituting the bulk portion of the resin composition layer, it is preferable that the second layer is sufficiently thick as compared with the first layer. Specifically, the thickness of the second layer is preferably at least 2 times, more preferably at least 4 times, more preferably at least 6 times, more preferably at least 8 times, at least 10 times, at least 12 times the thickness of the first layer Or more, 14 times or more, 16 times or more, 18 times or more, or 20 times or more. The thickness of the second layer may be usually 2000 times or less, 1000 times or less, or 500 times or less the thickness of the first layer. In one embodiment, the thickness of the second layer is preferably at least 3 mu m, more preferably at least 5 mu m, further preferably at least 7 mu m, at least 8 mu m, at least 9 mu m, or at least 10 mu m. The upper limit of the thickness of the second layer is preferably 100 占 퐉 or less, more preferably 80 占 퐉 or less, further preferably 60 占 퐉 or less, 50 占 퐉 or less, 40 占 퐉 or less, 30 占 퐉 or less or 20 占 퐉 or less.

The method of providing the first layer and the second layer to be bonded to each other is not particularly limited as long as it can be carried out so as to satisfy the conditions of i) to iii), and for example, 1) 2) applying the resin composition and drying the coated film to provide the second layer; 2) applying the first resin composition on the second layer and drying the coated film to provide the first layer; 3) And a method of laminating the first layer and the second layer so as to be bonded to each other.

In a preferred embodiment, the step of forming the integrated resin composition layer comprises:

(A1) a step of preparing a temporary resin sheet with a support comprising a support and a first layer having a thickness of less than 2 mu m made of a first resin composition bonded to the support, and

(B1) a step of applying a second resin composition on the first layer, and drying the coated film to provide a second layer, thereby forming an integrated resin composition layer (this embodiment will be referred to as &quot; first embodiment Quot;).

In the step (A1), a temporary resin sheet with a support comprising a support and a first layer of a first resin composition bonded to the support and having a thickness of less than 2 mu m is prepared.

The temporary resin sheet with a support can be produced, for example, by applying a first resin composition on a support and drying the coating to provide a first layer. Specifically, it can be produced by preparing a resin varnish obtained by dissolving a first resin composition in an organic solvent, applying the resin varnish on a support using a die coater or the like, and drying the coated film.

Examples of the organic solvent 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, Carbitol such as butyl carbitol, aromatic hydrocarbons such as toluene and xylene, and amide solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone. The organic solvent may be used singly or in combination of two or more kinds.

The coating film may be dried by a known drying method such as heating or hot air blowing. For example, 30 to 60 mass% of the organic solvent is used, the resin varnish is dried at 50 to 150 DEG C for 3 to 10 minutes, A first layer of the first resin composition may be formed on a support.

The temporary resin sheet with a support may further include a protective film on the surface not bonded to the support of the first layer (that is, the surface opposite to the support). Details of the protective film are as described above. When the temporary resin sheet with a support is used in the step (B1), it can be used by peeling the protective film.

In the step (B1), the second resin composition is coated on the first layer, and the coated film is dried to provide a second layer, thereby forming an integrated resin composition layer.

The application of the second resin composition and the drying of the coated film may be carried out in the same manner as the application of the first resin composition and drying of the coated film in the step (A1). The drying condition in the step (B1) may be the same as or different from the drying condition of the coated film in the step (A1). The drying temperature T _A1 (° C) in the step (A1) and the drying temperature T _B1 (° C) in the step (B1) _satisfy the relation of T _A1 <T _B1 in view of increasing the precision of the thickness of the obtained resin composition layer , More preferably satisfies the relationship of T _A1 +10? T _B1 , more preferably satisfies the relationship of T _A1 +20? T _B1 .

In another preferred embodiment, the step of forming the integrated resin composition layer includes:

(A2) preparing a temporary resin sheet with a protective film comprising a protective film and a second layer composed of a second resin composition bonded to the protective film, and

(B2) a step of applying the first resin composition on the second layer and drying the coating film to provide a first layer having a thickness of less than 2 탆, thereby forming an integrated resin composition layer (hereinafter, this embodiment Second embodiment &quot;).

The protective film used in the step (A2) is as described above. The temporary resin sheet with a protective film can be produced, for example, by applying a second resin composition onto a protective film and drying the applied film to provide a second layer. The application of the second resin composition and the drying of the coated film may be carried out in the same manner as the application of the first resin composition and the drying of the coated film in the step (A1).

The temporary resin sheet with a protective film may further include a second protective film on the surface not bonded to the protective film of the second layer (i.e., the surface opposite to the protective film). In such a case, the provisional resin sheet with the protective film may be provided to the step (B2) after the second protective film is peeled off.

In the step (B2), the application of the first resin composition and the drying of the coating film may be carried out in the same manner as the application of the first resin composition in the step (A1) and the drying of the coating film. The drying conditions in the step (B2) may be the same as or different from the conditions for drying the coated film in the step (A2). The drying temperature T _A2 (占 폚) in the step (A2) and the drying temperature T _B2 (?) In the step (B2) are preferably from the viewpoint of increasing the precision of the thickness of the obtained resin composition layer and the flexibility of the obtained resin composition layer. ° C) preferably satisfies the relationship of T _A2 > T _B2 , more preferably satisfies the relationship of T _A2 ≥T _B2 + 10, and more preferably satisfies the relationship of T _A2 ≥T _B2 + 20.

In the second embodiment, after the step (B2), a support body is provided on the surface of the resin composition layer which is not bonded to the protective film of the integrated resin composition layer. The details of the support are as described above.

In another embodiment, the step of forming the integrated resin composition layer includes:

(A3a) a step of preparing a temporary resin sheet with a support comprising a support and a first layer having a thickness of less than 2 mu m made of a first resin composition bonded to the support,

(A3b) preparing a temporary resin sheet with a protective film comprising a protective film and a second layer composed of a second resin composition bonded to the protective film, and

(B3) a step of laminating a temporary resin sheet with a support and a temporary resin sheet with a protective film so that the first layer and the second layer are bonded to each other (hereinafter, these embodiments are also referred to as &quot; third embodiment &quot;).

In the third embodiment, the step (A3a) and the step (A3b) may be carried out in the same manner as the step (A1) in the first embodiment and the step (A2) in the second embodiment, respectively.

In the step (B3), the temporary resin sheet with the support and the temporary resin sheet with the protective film are laminated so that the first layer and the second layer are bonded to each other.

Lamination of the temporary resin sheet with the support and the temporary resin sheet with the protective film is preferable because the workability is good and a uniform contact state is easily obtained. Therefore, it is preferable that the both sheets are laminated by roll pressing, press bonding or the like. Among them, a vacuum lamination method in which lamination under a reduced pressure is more preferable. The method of lamination may be batch or continuous.

The lamination treatment is generally carried out by setting the pressing pressure in the range of 1 kgf / cm 2 to 11 kgf / cm 2 (9.8 × 10 ⁴ N / m 2 to 107.9 × 10 ⁴ N / m 2) , And the compression time is set in the range of 5 seconds to 180 seconds and the air pressure is reduced under 20 mmHg (26.7 hPa) or less.

The lamination treatment can be carried out using a commercially available vacuum laminator. As a commercially available vacuum laminator, for example, vacuum press type laminator manufactured by Meikishesakusho Co., Ltd., and baked applicator manufactured by Nichigo Moton Co., Ltd., and the like can be given.

From the viewpoint of easily obtaining a resin composition layer having a desired resin area ratio over the entire resin sheet, the above-described first embodiment or second embodiment is preferable as the step of forming the integrated resin composition layer, Is more preferable.

[Printed circuit board]

The printed wiring board of the present invention comprises an insulating layer formed using the resin sheet with the support of the present invention.

In one embodiment, the printed wiring board of the present invention can be produced by a method including the following steps (I) and (II) using the resin sheet with the support of the present invention.

(I) The step of laminating the resin sheet with the support of the present invention on the inner layer substrate so that the resin composition layer is bonded to the inner layer substrate.

(II) A step of thermally curing the resin composition layer to form an insulating layer.

In the step (I), the resin sheet with the support of the present invention is laminated on the inner layer substrate so that the resin composition layer is bonded to the inner layer substrate.

The term "inner layer substrate" used in the step (I) means a substrate mainly composed of a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, Or circuit boards (circuits) patterned on both sides are formed. Further, when manufacturing a printed wiring board, an inner layer circuit board of an intermediate product in which an insulating layer and / or a conductor layer is to be formed is also included in the &quot; inner layer board &quot;

The lamination of the resin sheet with the support and the inner layer substrate in the step (I) may be carried out by any conventionally known method, but it is preferable that the resin composition layer is laminated so as to be bonded to the inner layer substrate by roll pressing or press bonding Do. The conditions for the lamination treatment can be the same as those described for the third embodiment of the [resin sheet with a support]. It is also preferable to laminate with an elastic material such as heat-resistant rubber so that the resin sheet with the support sufficiently follows the surface unevenness of the inner layer substrate (for example, the unevenness of the surface circuit of the inner layer circuit board).

In the step (I), the resin sheet with the support may be laminated on one side of the inner layer substrate or on both sides of the inner layer substrate.

After the step (I), the resin sheet having the support laminated on the inner layer substrate may be subjected to a treatment for heating and pressing and smoothing. The smoothing treatment is generally carried out by heating and pressing the resin sheet with the support under a normal pressure (atmospheric pressure) with a heated metal plate or a metal roll. The conditions for heating and pressing may be the same as those for the lamination treatment. The lamination treatment and the smoothing treatment may be carried out continuously using a commercially available vacuum laminator.

The support may be removed between step (I) and step (II), or may be removed after step (II).

In the step (II), the resin composition layer is thermally cured to form an insulating layer.

The conditions of thermal curing are not particularly limited, and conditions that are usually adopted when forming the insulating layer of the printed wiring board may be used.

For example, the thermosetting condition of the resin composition layer varies depending on the composition of the resin composition constituting the resin composition layer, but the curing temperature is in the range of 120 to 240 캜 (preferably in the range of 150 to 210 캜 , More preferably 170 占 폚 to 190 占 폚), and the curing time may be in the range of 5 minutes to 90 minutes (preferably 10 minutes to 75 minutes, more preferably 15 minutes to 60 minutes).

The resin composition layer may be preheated to a temperature lower than the curing temperature before thermosetting the resin composition layer. For example, before the resin composition layer is thermally cured, the resin composition layer is heated to a temperature of 50 ° C or more and less than 120 ° C (preferably 60 ° C or more and 110 ° C or less, more preferably 70 ° C or more and 100 ° C or less) (Preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes).

The insulating layer formed using the resin sheet with a support of the present invention exhibits a low coefficient of thermal expansion because it retains the bulk property that the content of the inorganic filler is high. In one embodiment, the insulating layer formed using the resin sheet with a support of the present invention preferably has an insulating layer of 30 ppm / ° C or less, more preferably 25 ppm / ° C or less, still more preferably 22 ppm / Can exhibit a coefficient of linear thermal expansion of 20 ppm / ° C or lower, 19 ppm / ° C or lower, 18 ppm / ° C or lower, 17 ppm / ° C or lower, 16 ppm / ° C or lower, 15 ppm / The lower limit of the linear thermal expansion coefficient of the insulating layer is not particularly limited, but is usually 1 ppm / DEG C or more.

The coefficient of linear thermal expansion of the insulating layer can be measured by a known method such as thermomechanical analysis. As a thermomechanical analyzer, for example, "Thermo Plus TMA8310" manufactured by Rigaku Corporation can be mentioned. In the present invention, the coefficient of linear thermal expansion of the insulating layer is a coefficient of linear thermal expansion in the plane direction of 25 占 폚 to 150 占 폚 when thermomechanical analysis is performed by a tensile weighting method.

Since the insulating layer formed using the resin sheet with a support of the present invention maintains a uniform composition as a bulk characteristic, it is possible to favorably exhibit desired characteristics as an insulating layer of a printed wiring board.

In one embodiment, the insulating layer formed using the resin sheet with a support of the present invention preferably has an insulating layer of 120 占 폚 or higher, more preferably 140 占 폚 or higher, more preferably 150 占 폚 or higher, even more preferably 155 占 폚 Or a glass transition temperature (Tg) of 160 DEG C or more, and exhibits sufficient strength. The upper limit of the Tg is not particularly limited, but is usually 250 DEG C or less. The Tg of the insulating layer can be measured by a known method such as thermomechanical analysis. As a thermomechanical analyzer, for example, "Thermo Plus TMA8310" manufactured by Rigaku Corporation can be mentioned.

In one embodiment, the insulating layer formed using the resin sheet with a support of the present invention preferably has an insulating layer of 0.05 or less, more preferably 0.04 or less, further preferably 0.03 or less, still more preferably 0.02 or less, or 0.01 Or less, contributing to prevention of heat generation at a high frequency, signal delay, and reduction of signal noise. The lower limit of the dielectric loss tangent is not particularly limited, but is usually 0.001 or more. The dielectric loss tangent of the insulating layer can be measured by a known method such as cavity resonator perturbation method. For example, "HP8362B" manufactured by Agilent Technologies Co., Ltd. may be mentioned as a dielectric resonance measurement apparatus of the cavity resonance method. In the present invention, the dielectric loss tangent of the insulating layer is a dielectric loss tangent measured by a cavity resonator perturbation method at a frequency of 5.8 GHz and a measurement temperature of 23 deg.

In the production of the printed wiring board, the step of (III) piercing the insulating layer, (IV) the step of roughening the insulating layer, and (V) the step of forming the conductor layer on the surface of the insulating layer. These processes (III) to (V) may be carried out according to various methods known to those skilled in the art, which are used in the production of printed wiring boards. When the support is removed after the step (II), the removal of the support is carried out between the step (II) and the step (III), between the step (III) and the step (IV) (V).

Step (III) is a step of perforating the insulating layer, whereby holes such as via holes and through holes can be formed in the insulating layer. For example, a hole can be formed in the insulating layer using a drill, a laser (carbon dioxide gas laser, YAG laser, etc.), plasma, or the like.

Step (IV) is a step of roughening the insulating layer. The order and condition of the harmonization treatment are not particularly limited, and a well-known sequence and conditions commonly used in forming the insulating layer of the printed wiring board can be adopted. For example, the swelling treatment by the swelling liquid, the coarsening treatment by the oxidizing agent, and the neutralization treatment by the neutralizing liquid can be carried out in this order to coarsen the insulating layer. The swelling liquid is not particularly limited, but an alkaline solution, a surfactant solution and the like can be mentioned, and an alkaline solution is preferable, and a sodium hydroxide solution and a potassium hydroxide solution are more preferable as the alkaline solution. Examples of swelling solutions that are commercially available include Swelling · Dip · Securigans P, Swelling · Dip · Securigans SBU manufactured by Atotech Japan Co., Ltd. and the like. The swelling treatment by the swelling liquid is not particularly limited, but can be carried out, for example, by immersing the swelling liquid at 30 to 90 DEG C for 1 minute to 20 minutes. The oxidizing agent is not particularly limited, and for example, an alkaline permanganic acid solution obtained by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide can be mentioned. The roughening treatment with an oxidizing agent such as an alkaline permanganic acid solution is preferably carried out by immersing in an oxidizing agent solution heated at 60 캜 to 80 캜 for 10 minutes to 30 minutes. The concentration of the permanganate in the alkaline permanganic acid solution is preferably 5% by mass to 10% by mass. Commercially available oxidizing agents include, for example, alkaline permanganic acid solutions such as Concentrate / Compact CP manufactured by Atotech Japan Co., Ltd., and Dozing Solution / Securigans P and the like. The neutralization solution is preferably an acidic aqueous solution, and as a commercial product, for example, Reduction Solution ㆍ Securigans P manufactured by Atotech Japan Co., Ltd. may be mentioned. The treatment with the neutralizing liquid can be carried out by immersing the treated surface subjected to the roughening treatment with the oxidizing agent solution in a neutralizing solution at 30 ° C to 80 ° C for 5 minutes to 30 minutes.

In the prior art including Patent Document 1, the inorganic filler existing on the surface of the insulating layer is removed in the roughening treatment, and irregularities are formed on the surface. It is believed that such irregularities exhibit an anchor effect with respect to the conductor layer, contributing to improvement in peel strength between the insulating layer and the conductor layer. However, if the content of the inorganic filler in the insulating layer is increased, deterioration of the peel strength between the insulating layer and the conductor layer can not be avoided even if such an anchor effect is caused by such unevenness. Further, The surface roughness sometimes becomes excessively high.

As described above, the resin composition layer included in the resin sheet with a support of the present invention has an abrupt composition gradient in the region near the bonding surface with the support. Such a composition gradient is formed by using the resin sheet with the support of the present invention And is also maintained in the insulating layer. Therefore, the insulating layer formed by using the resin sheet with the support of the present invention has a low proportion of the inorganic filler in the region near the surface, while retaining the bulk characteristic that the content of the inorganic filler is high. Thus, in the insulating layer formed using the resin sheet with the support of the present invention, the separation of the inorganic filler by the roughening treatment is less likely to occur than the insulating layer in the prior art. The insulating layer formed by using the resin sheet with a support of the present invention exhibits excellent peel strength with respect to the conductor layer after the roughening treatment but this is because in the balance between the content of the inorganic filler and the desorption of the inorganic filler, It is presumed that the surface contributing to the strength is reproduced.

In one embodiment, the arithmetic average roughness Ra of the surface of the insulating layer after the roughening treatment is preferably 180 nm or less, more preferably 150 nm or less, further preferably 120 nm or less, and even more preferably 110 nm or less. The insulating layer formed using the resin sheet with a support of the present invention exhibits excellent peel strength against the conductor layer even when Ra is 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less or 50 nm or less. The lower limit of the Ra value is not particularly limited, but is preferably 0.5 nm or more, more preferably 1 nm or more.

The arithmetic average roughness Ra of the surface of the insulating layer can be measured using a non-contact surface roughness meter. As a specific example of the non-contact surface roughness meter, &quot; WYKO NT3300 &quot; manufactured by Vico Instruments Co., Ltd. can be mentioned.

Step (V) is a step of forming a conductor layer on the surface of the insulating layer.

The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer comprises one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium do. The conductor layer may be a single metal layer or an alloy layer, and examples of the alloy layer include alloys of two or more metals selected from the above-mentioned group (for example, nickel-chromium alloy, copper-nickel alloy and copper- Alloy). Among them, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper or a nickel-chromium alloy, copper-nickel alloy or the like may be used from the viewpoints of general versatility, cost, Alloy or a copper-titanium alloy layer is preferable and a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper or an alloy layer of nickel-chromium alloy is more preferable, A metal layer is more preferable.

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 metals or alloys are stacked. 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 a nickel-chromium alloy.

The thickness of the conductor layer is generally 3 mu m to 35 mu m, preferably 5 mu m to 30 mu m, although depending on the design of the desired printed wiring board.

The conductor layer may be formed by plating. For example, the conductor 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-custom method or a pull-to-body method. Hereinafter, an example in which the conductor layer is formed by the semi-

First, a plating seed layer is formed on the surface of the insulating layer by electroless plating. Subsequently, a mask pattern is formed on the formed plating seed layer to expose a part of the plating seed layer corresponding to the desired wiring pattern. A metal layer is formed on the exposed plating seed layer by electrolytic plating, and then the mask pattern is removed. Thereafter, an unnecessary plating seed layer is removed by an etching process or the like, and a conductor layer having a desired wiring pattern can be formed.

In one embodiment, the peel strength between the insulating layer and the conductor layer after the roughening treatment is preferably 0.5 kgf / cm or more, more preferably 0.55 kgf / cm or more, still more preferably 0.60 kgf / cm or more, particularly preferably 0.0 &gt; kg / cm. &Lt; / RTI &gt; On the other hand, the upper limit value of the peel strength is not particularly limited, but is 1.2 kgf / cm or less, 0.9 kgf / cm or less, and the like. In the present invention, although the surface roughness Ra of the insulating layer after the roughening treatment is small, the insulating layer exhibiting such high peel strength can be formed. Therefore, the present invention significantly contributes to the micro-wiring of the printed wiring board.

In the present invention, the peeling strength between the insulating layer and the conductor layer refers to the peeling strength (peel strength at 90 degrees) when the conductor layer is peeled off in the direction perpendicular to the insulating layer (in the direction of 90 degrees) And the peel strength when the layer is peeled off in the direction perpendicular to the insulating layer (in the direction of 90 degrees) is measured by a tensile tester. As the tensile tester, for example, "AC-50C-SL" manufactured by TSE Co., Ltd. and the like can be mentioned.

[Semiconductor device]

A semiconductor device can be manufactured using the above printed wiring board.

Examples of such a semiconductor device include various semiconductor devices provided in an electric product (e.g., a computer, a mobile phone, a digital camera and a television) and a vehicle (e.g., a motorcycle, a car, a train, .

[ Example ]

Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited to these Examples. In the following description, &quot; part &quot; and &quot;% &quot; mean &quot; part by mass &quot; and &quot;% by mass &quot;, respectively, unless otherwise specified.

First, various measurement methods and evaluation methods will be described.

[Preparation of samples for measurement and evaluation]

(1) ground treatment of inner layer circuit board

Both surfaces of a glass cloth substrate epoxy resin double-sided copper clad laminate (thickness of copper foil of 18 mu m, substrate thickness of 0.3 mm, "R5715ES" manufactured by Panasonic DENKO CO., LTD.) On which an inner layer circuit was formed was etched by 1 mu m with "CZ8100" And the roughening treatment of the copper surface was carried out.

(2) Lamination of Resin Sheet with Support

The resin sheet with the support prepared in the examples and the comparative example was laminated by using a batch type vacuum press laminator (&quot; MVLP-500 &quot;, manufactured by Meikishesakusho Co., Ltd.) Both sides of the inner layer circuit board were laminated. The lamination treatment was carried out by reducing the pressure for 30 seconds to bring the air pressure to 13 hPa or less, followed by pressing at 100 DEG C and a pressure of 0.74 MPa for 30 seconds.

(3) Thermal curing of the resin composition layer

After laminating the resin sheet with the support, the resin composition layer was thermally cured under the conditions of 170 占 폚 for 30 minutes to form an insulating layer. Then, the support was peeled off.

(4) Harmonization processing

The inner-layer circuit board provided with the insulating layers on both sides was immersed in a swelling solution ("Swellling Dip-Sucrygan's P" manufactured by Atotech Japan Co., Ltd., sodium hydroxide aqueous solution containing diethylene glycol monobutyl ether) at 60 ° C for 5 minutes , Followed by immersion in an oxidizing agent ("Concentrate Compact CP" manufactured by Atotech Japan Co., Ltd .; an aqueous solution having a potassium permanganate concentration of about 6 mass% and a sodium hydroxide concentration of about 4 mass%) at 80 ° C for 20 minutes, (Reduction Solution · Securigans P, manufactured by Atotech Japan Co., Ltd., aqueous solution of sulfuric acid hydroxylamine) at 40 ° C for 5 minutes. Thereafter, it was dried at 80 DEG C for 30 minutes. The resulting substrate is referred to as &quot; evaluation substrate A &quot;.

(5) Formation of conductor layer

A conductor layer was formed on the surface of the insulating layer according to the semi-specific method.

That is, the evaluation substrate A was immersed in a solution for electroless plating containing PdCl ₂ at 40 ° C for 5 minutes and then immersed in an electroless copper plating solution at 25 ° C for 20 minutes to form a plating seed layer on the surface of the insulating layer . After annealing at 150 캜 for 30 minutes, an etching resist was provided on the plating seed layer, and the plating seed layer was patterned by etching. Subsequently, copper sulfate electroplating was performed to form a conductor layer having a thickness of 30 mu m, followed by annealing at 190 DEG C for 60 minutes. The obtained substrate is referred to as &quot; evaluation substrate B &quot;.

&Lt; Measurement of resin area ratio &

The cross section of the resin composition layer in the direction perpendicular to the surface of the support was observed by SEM and the distance from the boundary between the support and the resin composition layer was changed from d1 (mu m) to d2 , and _d2 is the distance from the boundary area a resin _d2 d3 to the region (㎛) from _{d2 (㎛) - - (㎛} ) in area a resin area _d1 to _d3 was measured. Then, the obtained A _{d1 - d2} Value and A _{d2 - d3} And the resin area ratio (kA _d1-d2 / A _d2-d3 ) was calculated from the values.

More specifically, the resin area is preserved as an image in the SEM observation image, and the resin portion is blackened and the inorganic filler portion other than the resin is made white so as to be converted into monochrome binarization (value conversion) The number of bits was defined as the area of the resin portion. SEM observation of the cross section of the resin composition layer was performed using a focused ion beam / scanning ion microscope (SMI3050SE, manufactured by SII Co., Ltd.), and the width of the measurement region was set to 7.5 mu m.

&Lt; Measurement of arithmetic average roughness (Ra value) >

The arithmetic average roughness (Ra value) of the surface of the insulating layer after the roughening treatment was measured according to the following procedure. The evaluation substrate A was measured using a non-contact surface roughness meter ("WYKO NT3300" manufactured by Vico Instruments Inc.) with a measurement range of 121 μm × 92 μm by a VSI contact mode and a 50 × lens, The Ra value was obtained from the numerical values. An average value of 10 points randomly selected for each evaluation substrate was obtained.

<Measurement of Peel Strength>

The peel strength between the insulating layer and the conductor layer was measured according to the following procedure. A sheath having a width of 10 mm and a length of 100 mm was put on the conductor layer of the evaluation board B and one end of the sheath was peeled and held by a holding tool and the load (kgf (mm)) when 35 mm was removed in the vertical direction at a rate of 50 mm / / cm) was measured. A tensile tester (AC-50C-SL, manufactured by TSE, Ltd.) was used for the measurement.

&Lt; Measurement of coefficient of linear thermal expansion and glass transition temperature (Tg)

The resin sheet with a support prepared in Examples and Comparative Examples was heated at 190 캜 for 90 minutes to thermally cure the resin composition layer. Then, the support was peeled off to obtain a sheet-like cured product. The obtained sheet-like cured product was cut into test pieces each having a width of about 5 mm and a length of about 15 mm and subjected to thermomechanical analysis by the tensile weighting method using a thermomechanical analyzer ("Thermo Plus TMA8310" manufactured by Rigaku Corporation) Respectively. Specifically, after the test piece was mounted on the thermomechanical analyzer, the test piece was continuously measured twice under the measurement conditions of a load of 1 g and a temperature raising rate of 5 캜 / minute. In the second measurement, the coefficient of linear thermal expansion (ppm / DEG C) and the glass transition temperature (Tg) in the range of 25 DEG C to 150 DEG C were calculated.

&Lt; Measurement and evaluation of dielectric loss tangent &

The resin sheet with a support prepared in Examples and Comparative Examples was heated at 190 캜 for 90 minutes to thermally cure the resin composition layer. Then, the support was peeled off to obtain a sheet-like cured product. The obtained sheet-like cured product was cut with a test piece having a width of 2 mm and a length of 80 mm and measured at a measurement frequency of 5.8 GHz using a coaxial resonance perturbation permittivity measurement device ("HP8362B" manufactured by Ajin Tec Technology Co., Ltd.) Lt; 0 &gt; C. The two test pieces were measured and the average value was calculated.

The varnishes of the resin compositions 1 to 6 used in Examples and Comparative Examples were prepared as follows.

Preparation Example 1 Preparation of varnish of Resin Composition 1

10 parts of a bisphenol type epoxy resin ("ZX1059" manufactured by Shinnitetsu Sumikin Kagaku Co., Ltd., a 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent 169), a biphenyl type epoxy resin (Nippon Kayaku (NC3000H, epoxy equivalent: about 290) were dissolved in 700 parts of methyl ethyl ketone (MEK) while heating with stirring. After cooling to room temperature, 20 parts of a triazine skeleton-containing phenol novolac curing agent ("LA-7054" manufactured by DIC Corporation, a MEK solution of 60 mass% of a nonvolatile component, a phenolic hydroxyl group equivalent 124) 1 part of a curing accelerator (4-dimethylaminopyridine (DMAP), a 10% by mass solid solution of MEK), a polyvinyl butyral resin solution (KS-1 manufactured by Sekisui Chemical Co., Ltd.)占 폚, and a mixed solution of 15 mass% of a nonvolatile component having an ethanol: toluene mass ratio of 1: 1) were mixed to prepare a varnish of the resin composition 1.

Preparation Example 2 Preparation of Varnish of Resin Composition 2

, 10 parts of a bisphenol type epoxy resin ("ZX1059" manufactured by Shinnets Tetsu Sumikin Kagaku Co., Ltd., epoxy equivalent weight 169), 40 parts of a biphenyl type epoxy resin (NC3000H manufactured by Nippon Kayaku Co., , And 30 parts of phenoxy resin ("YL7553BH30" manufactured by Mitsubishi Chemical Corporation, solid content 30% by mass) was dissolved by heating in 900 parts of MEK while stirring. 60 parts of an active ester type curing agent ("HPC8000-65T" manufactured by DIC Corporation, an active equivalent weight of about 223, and a toluene solution of a nonvolatile component of 65% by mass), 60 parts of a phenazine novolac type curing agent containing a triazine skeleton , 15 parts of a phenolic hydroxyl group equivalent 124), 20 parts of N-phenyl-3-aminopropyltrimethoxysilane (manufactured by Shinetsu Kagakukogyo Co., Ltd., &quot; KBM -573 "), 3 parts of a curing accelerator (DMAP, 10% by mass of solid content) and 200 parts of cyclohexanone were mixed to prepare a varnish of Resin Composition 2.

&Lt; Preparation Example 3 > Preparation of varnish of resin composition 3

Instead of 20 parts of a polyvinyl butyral resin solution ("KS-1" manufactured by Sekisui Chemical Co., Ltd., a glass transition temperature of 105 ° C, a 15% by mass nonvolatile component of ethanol: toluene mass ratio of 1: 1) Except that 50 parts of an epoxy group-containing acrylic acid ester copolymer ("SG-80H" manufactured by Nagase ChemteX Corporation, MEK solution of 18 mass% of a nonvolatile component) was used in place of the epoxy resin Lt; / RTI &gt;

Preparation Example 4 Preparation of Varnish of Resin Composition 4

("HPC8000-65T" manufactured by DIC Corporation) was used in place of 60 parts of an active ester type curing agent ("HPC8000-65T" manufactured by DIC Corporation, active agent equivalent approximately 223, toluene solution having a nonvolatile component of 65% , 30 parts of an active agent equivalent of about 223 and a toluene solution of a nonvolatile component of 65% by mass) and 30 parts of a nanosilica filler slurry (YA050C-MJE manufactured by Adomex Co., Ltd., average particle diameter: 50 nm, 50 parts by mass of a MEK slurry) was used in place of 40 parts by mass of the resin composition.

Preparation Example 5 Preparation of varnish of Resin Composition 5

15 parts of a bisphenol-type epoxy resin ("ZX1059" manufactured by Shinnitetsu Sumikin Kagaku Co., Ltd., epoxy equivalent 169), 15 parts of a biphenyl-type epoxy resin (NC3000H manufactured by Nippon Kayaku Co., And 5 parts of a naphthalene type tetrafunctional epoxy resin (epoxy equivalent 162, "HP-4700" manufactured by DIC Corporation) were dissolved by heating in a mixed solvent of 20 parts of MEK and 10 parts of cyclohexanone with stirring. After cooling to room temperature, 30 parts of a triazine skeleton-containing phenol novolak type curing agent (phenolic hydroxyl group equivalent of about 124, "LA-7054" manufactured by DIC Corporation, 60% by mass of a nonvolatile component) , 1 part of a curing accelerator (DMAP, 10% by mass of a solid content MEK solution) and 1 part of a spherical silica surface-treated with an aminosilane coupling agent (KBM573 manufactured by Shinetsu Kagaku Co., , 125 parts of a polyvinyl butyral resin solution ("KS-1" manufactured by Sekisui Chemical Co., Ltd., glass transition temperature: 105 캜, a nonvolatile component 10 parts by mass of a 15: 1 mass% ethanol: toluene mass ratio of 1: 1) were mixed and uniformly dispersed with a high-speed rotary mixer to prepare a varnish of the resin composition 5.

&Lt; Preparation Example 6 > Preparation of varnish of resin composition 6

, 20 parts of a bisphenol type epoxy resin ("ZX1059" manufactured by Shinnets Tetsu Sumikin Kakaku Co., Ltd., epoxy equivalent 169), 40 parts of a biphenyl type epoxy resin (NC3000H manufactured by Nippon Kayaku Co., , 15 parts of phenoxy resin ("YL7553BH30" manufactured by Mitsubishi Chemical Corporation, 30% by mass of solid content) was dissolved by heating in 20 parts of solvent naphtha with stirring. 60 parts of an active ester type curing agent ("HPC8000-65T" manufactured by DIC Corporation, an active equivalent weight of about 223, and a toluene solution of a nonvolatile component of 65% by mass), 60 parts of a phenazine novolac type curing agent containing a triazine skeleton , 15 parts of an MEK solution of 60 mass% of a non-volatile component of &quot; LA-7054 &quot;, phenolic hydroxyl group equivalent 124), 3 parts of a curing accelerator (DMAP, 10 mass% of solid content solution), 3 parts of an amino silane coupling agent 375 parts of spherical silica ("SOC1" manufactured by Adomex Co., Ltd., average particle diameter 0.24 μm, carbon amount per unit surface area 0.36 mg / m 2) surface-treated with a high-speed rotary mixer And uniformly dispersed to prepare a varnish of Resin Composition 6.

Example 1 Production of Resin Sheet 1 with Support

A PET film (AL5 manufactured by LINTEC CO., LTD.) Having a thickness of 38 mu m was prepared as a support. The varnish of the resin composition 1 was uniformly coated on the support by a die coater and the coating film was dried at 80 DEG C for 3 minutes to form a first layer having a thickness of 0.5 mu m. Then, the varnish of the resin composition 5 was uniformly coated on the first layer with a die coater so that the total thickness of the resin composition layer after drying was 10 탆, and the coating film was dried at 80 to 120 캜 (average 100 캜) for 4 minutes To prepare a resin sheet 1 with a support.

Example 2 Production of Resin Sheet 2 with Support

A resin sheet 2 with a support was prepared in the same manner as in Example 1 except that the varnish of the resin composition 2 was used instead of the varnish of the resin composition 1 to form the first layer.

Example 3 Production of Resin Sheet 3 with Support

A resin sheet 3 with a support was prepared in the same manner as in Example 1 except that the varnish of the resin composition 5 was used instead of the varnish of the resin composition 6 to form the second layer.

Example 4 Production of Resin Sheet 4 with Support

Except that the first layer was formed using the varnish of the resin composition 2 instead of the varnish of the resin composition 1 and the second layer was formed using the varnish of the resin composition 6 instead of the varnish of the resin composition 5, In the same manner, a resin sheet 4 with a support was produced.

Example 5 Production of Resin Sheet 5 with Support

Except that the first layer was formed using the varnish of the resin composition 3 instead of the varnish of the resin composition 1 and the second layer was formed using the varnish of the resin composition 6 instead of the varnish of the resin composition 5, In the same manner, a resin sheet 5 with a support was obtained.

Example 6 Production of Resin Sheet 6 with Support

Resin sheet 6 with a support was obtained in the same manner as in &quot; (Production of resin sheet 1 with a support) &quot; except that resin varnish 4 was used in place of resin varnish 1 and resin varnish 6 was used in place of resin varnish 5.

&Lt; Comparative Example 1 > Production of resin sheet 7 with a support

A PET film (AL5 manufactured by LINTEC CO., LTD.) Having a thickness of 38 mu m was prepared as a support. Then, the varnish of the resin composition 5 was uniformly coated on the support by a die coater so that the thickness of the resin composition layer after drying was 10 탆, and the coating film was dried at 80 to 120 캜 (average 100 캜) for 4 minutes, Whereby an adhered resin sheet 7 was produced.

&Lt; Comparative Example 2 > Production of resin sheet 8 with a support

A resin sheet 8 with a support was produced in the same manner as in Comparative Example 1 except that the varnish of the resin composition 6 was used instead of the varnish of the resin composition 5.

The evaluation results are shown in Table 2.

Claims (11)

A resin sheet with a support comprising a support and a resin composition layer bonded to the support and having an inorganic filler content of 50 mass%
In the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area A _0-1 in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 1 탆, The resin area A _1-2 in the region of from 1 탆 to 2 탆 satisfies the relationship of A _0-1 / A _1-2 > 1.1. A resin sheet with a support comprising a support and a resin composition layer bonded to the support and having an inorganic filler content of 50 mass%
In the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area A _0-0.5 in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 0.5 탆, Is in the range of 0.5 占 퐉 to 1 占 퐉, the resin area A _0.5-1 satisfies the relation of A _0-0.5 / A _0.5-1 > 1.1. The resin composition according to claim 1, wherein a resin area A _0.5-d in a region where the distance from the boundary between the support and the resin composition layer is 0.5 탆 to d 탆 in a cross section of the resin composition layer in a direction perpendicular to the surface of the support , the distance from the boundary area a _{d -0.5D} resin in the area from d㎛ to _{0.5D㎛, 0.9 ≤ kA 0 .5-} d / a d -0.5D ≤ 1.1 ( where, k is k = D is a coefficient satisfying | d-0.5D | /0.5-d |, d is a number satisfying 0.5 <d <0.5D, and D is a thickness of the resin composition layer) Sheet. Providing a first layer of a first resin composition having a thickness of less than 2 占 퐉 and a second layer of a second resin composition to be bonded to each other to form an integrated resin composition layer,
The content of the inorganic filler in the resin composition layer is 50% by mass or more,
The surface of the side of the resin composition layer originated from the first layer is bonded to the support,
In the cross section of the resin composition layer in the direction perpendicular to the surface of the support, the resin area A _0-1 in the region where the distance from the boundary between the support and the resin composition layer is 0 탆 to 1 탆, Wherein the resin area A _1-2 in the region of from 1 占 퐉 to 2 占 퐉 satisfies the relationship of A _0-1 / A _1-2 > 1.1. The method according to claim 4, wherein the step of forming the resin composition layer comprises:
(A1) a step of preparing a temporary resin sheet with a support comprising a support and a first layer having a thickness of less than 2 mu m made of a first resin composition bonded to the support, and
(B1) applying a second resin composition onto the first layer, and drying the coated film to provide a second layer, thereby forming an integrated resin composition layer. 5. The method of claim 4, wherein the thickness of the first layer is less than 1 micron. 5. The method according to claim 4, wherein the first resin composition comprises an inorganic filler having an average particle diameter of 500 nm or less. The method according to claim 4, wherein the content of the inorganic filler in the first resin composition is 40 mass% or less. 9. The method according to any one of claims 4 to 8, wherein the content of the inorganic filler in the second resin composition is higher than 50 mass%. A printed wiring board comprising an insulating layer formed using the resin sheet with a support according to any one of claims 1 to 3.  A semiconductor device comprising the printed wiring board according to claim 10.

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