JP6291714B2 - Insulating resin sheet - Google Patents

Description

  The present invention relates to an insulating resin sheet useful for forming an insulating layer of a multilayer printed wiring board, a multilayer printed wiring board using the insulating resin sheet, and a semiconductor device.

  As a manufacturing technique of a multilayer printed wiring board, a manufacturing method by a built-up method in which insulating layers and conductor layers are alternately stacked on a core substrate is known. Insulating layer formation uses an insulating resin sheet in which a thermosetting resin composition layer is exclusively formed on a plastic film. The insulating resin sheet is laminated on the inner circuit board, the plastic film is peeled off, and then the thermosetting is performed. An insulating layer is formed by thermosetting the resin. On the other hand, multilayer printed wiring boards tend to be made thinner and thinner due to the recent needs for miniaturization of electronic devices and electronic components. In order to maintain the mechanical strength of the multilayer printed wiring board amid this reduction in thickness, Patent Document 1 proposes to apply a prepreg to an insulating resin sheet for built-up. On the other hand, since the prepreg includes a glass cloth, a new problem arises in that it is inferior in workability such as via hole formation when applied to an interlayer insulating layer.

  As another method for maintaining the mechanical strength of the multilayer printed wiring board accompanying thinning, Patent Document 2 discloses a method using an adhesive film having a heat-resistant resin layer between thermosetting resin composition layers. .

International Publication No. 2009/119621 Pamphlet International Publication No. 2001/097582 Pamphlet

According to the study by the present inventors, when an interlayer insulating layer of a multilayer printed wiring board is formed with an insulating resin sheet having such a heat-resistant film layer, a via hole is subsequently formed in the insulating layer, and when performing a desmear treatment, It has been found that there is a problem that a via step is formed between the heat-resistant film layer and the thermosetting resin composition layer, resulting in a distorted via shape. In addition, it has been found that this problem becomes apparent in small-diameter via holes as the diameter of via holes is reduced along with the downsizing of electronic equipment.

As a result of intensive studies in view of the above problems, the present inventors have determined that the insulating ratio of the heat-resistant film layer and the thermosetting resin composition layer by controlling the etching ratio of the cured product within a certain range. The inventors have found that the problem of the via shape of the insulating layer formed of the resin sheet can be solved, and have completed the present invention.

That is, the present invention includes the following contents.
[1] An insulating resin sheet having a heat-resistant film and a thermosetting resin composition layer formed on both surfaces of the heat-resistant film, the etching amount per unit area of the heat-resistant film (E1) and the thermosetting property The insulating resin sheet whose etching amount per unit area (E2) of the hardened | cured material of a resin composition layer is E1 / E2 = 0.5-3.
[2] The etching amount per unit area of the heat-resistant film (E1) and the etching amount per unit area of the cured product of the thermosetting resin composition layer (E2) are E1 / E2 = 0.5-2 The insulating resin sheet according to [1].
[3] The etching amount (E1) per unit area of the heat-resistant film and the etching amount (E2) per unit area of the cured product of the thermosetting resin composition layer are E1 / E2 = 0.5 to 1. 5. The insulating resin sheet according to [1], which is 5.
[4] The etching amount per unit area of the heat-resistant film (E1) and the etching amount per unit area of the cured product of the thermosetting resin composition layer (E2) are E1 / E2 = 0.7 to 1. 3. The insulating resin sheet according to [1], which is 3.
[5] Etching amount per unit area of the heat-resistant film (E1), the thermosetting resin composition, a linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film, and the thermosetting resin composition layer The insulating resin sheet according to any one of [1] to [4], wherein an absolute value of a difference in linear thermal expansion coefficient (C2) at 25 to 150 ° C of the cured product is 30 ppm / ° C or less.
[6] Etching amount per unit area of the heat-resistant film (E1), the thermosetting resin composition, a linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film, and the thermosetting resin composition layer The insulating resin sheet according to any one of [1] to [4], wherein an absolute value of a difference in linear thermal expansion coefficient (C2) at 25 to 150 ° C of the cured product is 25 ppm / ° C or less.
[7] Etching amount per unit area of the heat-resistant film (E1) and the thermosetting resin composition 25 to 150 ° C. linear thermal expansion coefficient (C1) of the heat-resistant film and the thermosetting resin composition layer The insulating resin sheet according to any one of [1] to [4], wherein the absolute value of the difference in linear thermal expansion coefficient (C2) at 25 to 150 ° C of the cured product is 20 ppm / ° C or less.
[8] Etching amount per unit area of the heat-resistant film (E1), the thermosetting resin composition, a linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film, and the thermosetting resin composition layer The insulating resin sheet according to any one of [1] to [4], wherein the absolute value of the difference in linear thermal expansion coefficient (C2) at 25 to 150 ° C of the cured product is 15 ppm / ° C or less.
[9] The insulating resin sheet according to any one of [1] to [8], wherein the heat-resistant film has a linear thermal expansion coefficient (C1) of 25 to 150 ° C of 30 ppm / ° C or less.
[10] The heat-resistant film is selected from the group consisting of a polyethylene naphthalate film, a polyphenylene sulfide film, a polyether ether ketone film, a polyimide film, a polyetherimide film, an aramid film, a polyamideimide film, and a liquid crystal polymer film. ] The insulating resin sheet according to any one of [9] to [9].
[11] The insulating resin sheet according to any one of [1] to [10], wherein the heat-resistant film has a thickness of 2 μm to 30 μm.
[12] The insulating resin sheet according to any one of [1] to [11], wherein the thermosetting resin composition layer contains an epoxy resin, a curing agent, and an inorganic filler.
[13] The insulating resin sheet according to [12], wherein the epoxy resin is at least one selected from a naphthol type epoxy resin, a naphthalene type epoxy resin, a biphenyl type epoxy resin, and a naphthylene ether type epoxy resin.
[14] The insulating resin sheet according to [12], wherein the content of the inorganic filler in the thermosetting resin composition layer is 30% by weight or more and 90% by weight or less.
[15] The insulating resin sheet according to [12], wherein the content of the inorganic filler in the thermosetting resin composition layer is 40% by weight or more and 80% by weight or less.
[16] The insulating resin sheet according to any one of [1] to [15], wherein the linear thermal expansion coefficient after curing of the thermosetting resin composition layer is 50 ppm / ° C. or less.
[17] The insulating resin sheet according to any one of [1] to [15], wherein the linear thermal expansion coefficient after curing of the thermosetting resin composition layer is 40 ppm / ° C. or less.
[18] The insulating resin sheet according to any one of [1] to [15], wherein the linear thermal expansion coefficient after curing of the thermosetting resin composition layer is 30 ppm / ° C. or less.
[19] The insulating resin sheet according to any one of [1] to [18], which is for a buildup layer of a multilayer printed wiring board.
[20] One of the thermosetting resin composition layers formed on both surfaces of the heat-resistant film is a thermosetting resin composition layer for forming a conductor layer, and the other is a thermosetting resin composition for laminating an inner circuit board. Wherein the thickness of the thermosetting resin composition layer for forming the conductor layer is 2 μm or more and 18 μm or less, and the thickness of the thermosetting resin composition layer for the inner circuit board laminate is 5 μm or more and 120 μm or less. 19] The insulating resin sheet.
[21] The insulating resin sheet according to [20], wherein the thermosetting resin composition layer for laminating the inner layer circuit board has a minimum melt viscosity of 100 poise or more and 5000 poise or less.
[22] The insulating resin sheet according to any one of [19] to [21], which has a protective film on at least the outer surface of the thermosetting resin composition layer for forming a conductor layer.
[23] A method for producing a multilayer printed wiring board comprising the following steps (A) to (F):
(A) A step of laminating the insulating resin sheet according to claim 22 on one side or both sides of the inner layer circuit board, with the thermosetting resin composition layer for laminating the inner layer circuit board facing the inner layer circuit board,
(B) a step of thermosetting the thermosetting resin composition layer of the insulating resin sheet to form an insulating layer;
(C) a step of peeling off the protective film layer,
(D) forming a via hole by drilling the insulating layer;
(E) A step of roughening the surface of the insulating layer (thermosetting resin composition layer for forming a conductor layer),
(F) A step of plating the surface of the insulating layer after the roughening treatment to form a conductor layer.
[24] A multilayer printed wiring board having an insulating layer formed of the insulating resin sheet according to any one of [1] to [22].
[25] The multilayer printed wiring board according to [24], wherein the via hole has an opening diameter of 100 μm or less.
[26] The multilayer printed wiring board according to [24], wherein the via hole has an opening diameter of 75 μm or less.
[27] The multilayer printed wiring board according to [24], wherein the opening diameter of the via hole is 50 μm or less.
[28] A semiconductor device including the multilayer printed wiring board according to any one of [24] to [28].

Since the insulating resin sheet of the present invention includes a heat-resistant film layer, the mechanical strength can be improved when the insulating layer is formed, and the workability in forming via holes and the like is superior to that when glass cloth is used. In addition, even in a small-diameter via hole, distortion of the via shape is suppressed, and a favorable via hole can be formed.

  The present invention is described in detail below.

  The insulating resin sheet of the present invention has a heat resistant film and a thermosetting resin composition layer formed on both surfaces of the heat resistant film.

Moreover, 150 degreeC or more is preferable, as for the glass transition temperature of a heat-resistant film, 170 degreeC or more is more preferable, 200 degreeC or more is more preferable, and 250 degreeC or more is more preferable. The upper limit is not particularly limited, but generally it is often 500 ° C. or lower. It can be measured according to the method described in “Glass transition temperature”, JIS K 7179, specifically, thermal mechanical analysis (TMA), dynamic mechanical analysis (DMA), and the like. Examples of thermomechanical analysis (TMA) include TMA-SS6100 (manufactured by Seiko Instruments Inc.), TMA-8310 (manufactured by Rigaku Corporation), and the like. Examples of dynamic mechanical analysis (DMA) include: And DMS-6100 (manufactured by Seiko Instruments Inc.). Further, when the glass transition temperature is higher than the decomposition temperature and the glass transition temperature is not actually observed, the decomposition temperature can be used as a reference instead of the glass transition temperature. The decomposition temperature here is defined as a temperature at which the mass reduction rate when measured according to the method described in JIS K 7120 is 5%.

The coefficient of linear thermal expansion of the heat resistant film is preferably 30 ppm / ° C. or less, more preferably 20 ppm / ° C. or less, more preferably 15 ppm / ° C. or less, more preferably 10 ppm / ° C. or less, more preferably 5 ppm. Those having a temperature of / ° C. or lower are more preferable. The lower limit is preferably −20 ppm / ° C. or higher, more preferably −15 ppm / ° C. or higher, and more preferably −10 ppm / ° C. or higher from a practical viewpoint.

  Examples of the heat resistant film include those in the form of a heat resistant resin such as polyimide, liquid crystal polymer, polyphenylene sulfide, polyethylene naphthalate, polyether ether ketone, polybenzimidazole, aramid, polyamide imide, and polyether imide. Specifically, “Upilex-S” manufactured by Ube Industries, Ltd., “Kapton” manufactured by Toray DuPont Co., Ltd., “Pomilan” manufactured by Arakawa Chemical Industries, Ltd., “APICAL” manufactured by Kaneka Corporation. "Aramid film", "Mikutron" manufactured by Toray Industries, Inc., "Aramika" manufactured by Asahi Kasei Kogyo Co., Ltd., and liquid crystal polymer film, "Bexstar" manufactured by Kuraray Co., Ltd., "Biac" manufactured by Japan Gore-Tex Corporation, Examples of the polyether ether ketone include “Sumilite FS-1100C”.

The heat-resistant film may be subjected to surface treatment such as mud treatment or corona treatment. The release treatment may be performed with a release agent such as a silicone resin release agent, an alkyd resin release agent, or a fluororesin release agent.

  The thickness of the heat resistant film is preferably 2 μm or more and 30 μm or less. If the thickness is less than 2 μm, the mechanical strength of the insulating layer or the multilayer printed wiring board may not be sufficient. If the thickness exceeds 30 μm, the mechanical strength may not be suitable for manufacturing a thin multilayer printed wiring board.

The insulating resin sheet of the present invention has a thermosetting resin composition layer on both surfaces of the heat-resistant film. As a thermosetting resin composition, what contains an epoxy resin, a hardening | curing agent, and an inorganic filler is preferable.

Although it does not specifically limit as an epoxy resin used for this invention, It is preferable to contain the epoxy resin which has a 2 or more epoxy group in 1 molecule. Specifically, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthol type epoxy resin, naphthalene Type epoxy resin, naphthylene ether type epoxy resin, glycidyl amine type epoxy resin, glycidyl ester type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, anthracene type epoxy resin, linear aliphatic epoxy resin, butadiene structure Epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring-containing epoxy resin, cyclohexanedimethanol type epoxy resin, trimethylol type epoxy resin, halo Emissions epoxy resins. These may be used alone or in combination of two or more.

Among these, bisphenol A type epoxy resin, bisphenol F type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, naphthylene ether from the viewpoint of improving heat resistance, insulation reliability and fluidity Type epoxy resins, glycidyl ester type epoxy resins, anthracene type epoxy resins, and epoxy resins having a butadiene structure are preferred. In particular, it is more preferable that the epoxy resin contains one or more selected from naphthol type epoxy resins, naphthalene type epoxy resins, biphenyl type epoxy resins and naphthylene ether type epoxy resins. Specifically, for example, bisphenol A type epoxy resin (“Epicoat 828EL”, “YL980” manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resin (“jER806H”, “YL983U” manufactured by Mitsubishi Chemical Corporation), Naphthalene type bifunctional epoxy resin (“HP4032”, “HP4032D”, “HP4032SS”, “EXA4032SS” manufactured by DIC Corporation), naphthalene type tetrafunctional epoxy resin (“HP4700”, “HP4710” manufactured by DIC Corporation), Naphthol type epoxy resin (“ESN-475V” manufactured by Nippon Steel Chemical Co., Ltd.), epoxy resin having butadiene structure (“PB-3600” manufactured by Daicel Chemical Industries, Ltd.), epoxy resin having biphenyl structure (Nipponization) “NC3000H”, “NC3000L”, “NC31” manufactured by Yakuhin Co., Ltd. "00", "YX4000", "YX4000H", "YX4000HK", "YL6121") manufactured by Mitsubishi Chemical Corporation, anthracene type epoxy resin ("YX8800" manufactured by Mitsubishi Chemical Corporation), naphthylene ether type epoxy resin (DIC) “EXA-7310”, “EXA-7311”, “EXA-7311L”, “EXA7311-G3”), glycidyl ester type epoxy resin (“EX711”, “EX721” manufactured by Nagase ChemteX Corp.) ("R540" manufactured by Printec Co., Ltd.).

The epoxy resin can improve the embedding property of the inner layer circuit board of the thermosetting resin composition layer by including a liquid epoxy resin. Furthermore, it is preferable to use a liquid epoxy resin and a solid epoxy resin in combination. The liquid epoxy resin is preferably an aromatic epoxy resin having two or more epoxy groups in one molecule and a liquid at a temperature of 20 ° C. The solid epoxy resin has three or more epoxy groups in one molecule. And an aromatic epoxy resin that is solid at a temperature of 20 ° C. is preferable. In addition, the aromatic epoxy resin as used in the field of this invention means the epoxy resin which has an aromatic ring structure in the molecule | numerator. When using a liquid epoxy resin and a solid epoxy resin together as an epoxy resin, the blending ratio (liquid epoxy resin: solid epoxy resin) is a mass ratio in terms of providing a balance of the cured physical properties of the thermosetting resin composition. The range of 1: 0.1 to 1: 2 is preferable, the range of 1: 0.3 to 1: 1.8 is more preferable, and the range of 1: 0.6 to 1: 1.5 is more preferable.

The liquid epoxy resin is preferably bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, glycidyl ester type epoxy resin, naphthalene type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, naphthalene. A type epoxy resin is more preferable. You may use these 1 type or in combination of 2 or more types. Solid epoxy resins include tetrafunctional naphthalene type epoxy resins, cresol novolac type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol epoxy resins, naphthol type epoxy resins, anthracene type epoxy resins, biphenyl type epoxy resins, and naphthylene ethers. Type epoxy resin is preferable, and naphthol type epoxy resin and biphenyl type epoxy resin are more preferable. You may use these 1 type or in combination of 2 or more types.

  In the thermosetting resin composition of the present invention, from the viewpoint of improving the insulation reliability of the cured product of the thermosetting resin composition, when the nonvolatile component in the thermosetting resin composition is 100% by mass, epoxy is used. The resin content is preferably 3 to 40% by mass, more preferably 5 to 35% by mass, and still more preferably 10 to 30% by mass. In particular, in the thermosetting resin composition layer for embedding the inner layer circuit board, when the resin component in the thermosetting resin composition layer is 100% by mass in terms of improving embedding properties, the liquid epoxy resin The content is preferably 1 to 35% by mass, more preferably 3 to 30% by mass, and even more preferably 6 to 25% by mass.

The curing agent used in the present invention is not particularly limited, and examples thereof include phenolic curing agents, active ester curing agents, cyanate ester curing agents, benzoxazine curing agents, acid anhydride curing agents, and the like. It is preferable to use at least one selected from a system curing agent, an active ester curing agent and a cyanate ester curing agent. These may be used alone or in combination of two or more.

  Although it does not restrict | limit especially as a phenol type hardening | curing agent, A biphenyl type hardening | curing agent, a naphthalene type hardening | curing agent, a phenol novolak type hardening | curing agent, a naphthylene ether type hardening | curing agent, and a triazine skeleton containing phenol type hardening | curing agent are preferable. Specifically, biphenyl type curing agents MEH-7700, MEH-7810, MEH-7785 (Maywa Kasei Co., Ltd.), naphthalene type curing agents NHN, CBN, GPH (Nippon Kayaku Co., Ltd.), SN170, SN180, SN190, SN475, SN485, SN495, SN375, SN395 (manufactured by Nippon Steel Chemical Co., Ltd.), EXB9500 (manufactured by DIC Corporation), phenol novolac type curing agent TD2090 (manufactured by DIC Corporation), Examples include naphthylene ether type curing agent EXB-6000 (manufactured by DIC Corporation). Specific examples of the triazine skeleton-containing phenolic curing agent include LA3018, LA7052, LA7054, LA1356 (manufactured by DIC Corporation) and the like. In particular, naphthalene type curing agents and triazine skeleton-containing phenolic curing agents are more suitable.

Active ester-based curing agents generally include compounds having two or more ester groups with high reaction activity in one molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and heterocyclic hydroxy compounds. Is preferably used. The active ester curing agent is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester 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, phenolphthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol , Dicyclopentadienyl diphenol, phenol novolac and the like. 1 type (s) or 2 or more types can be used for an active ester type hardening | curing agent. Specifically, an active ester curing agent having a dicyclopentadienyl diphenol structure, an active ester curing agent having a naphthalene structure, an active ester curing agent that is an acetylated product of phenol novolac, and a benzoylated phenol novolac A certain active ester-based curing agent or the like is preferable, and in particular, an active ester containing a dicyclopentadienyl diphenol structure in that the melt viscosity of the thermosetting resin composition layer can be lowered and the embedding property can be improved. A system hardening agent is more preferable. Examples of commercially available products include EXB9451, EXB9460, EXB9460S-65T, HPC8000-65T (manufactured by DIC Corporation, active group equivalent of about 223), and an activity that is an acetylated product of phenol novolak. DC808 (produced by Mitsubishi Chemical Corporation, active group equivalent of about 149) as an ester-based curing agent, YLH1026 (produced by Mitsubishi Chemical Corporation, active group equivalent of about 200) as an active ester-based curing agent that is a benzoylated phenol novolak, YLH1030 (Mitsubishi Chemical Corporation, active group equivalent of about 201), YLH1048 (Mitsubishi Chemical Corporation, active group equivalent of about 245) and the like can be mentioned.

Although there is no restriction | limiting in particular as cyanate ester type hardening | curing agent, Novolac type (phenol novolak type, alkylphenol novolak type, etc.) cyanate ester type hardening agent, dicyclopentadiene type cyanate ester type hardening agent, bisphenol type (bisphenol A type, bisphenol) Fate, bisphenol S type, etc.) cyanate ester curing agents, and prepolymers in which these are partially triazines. Although the weight average molecular weight of a cyanate ester hardening | curing agent is not specifically limited, 500-4500 are preferable and 600-3000 are more preferable. Specific examples of the cyanate ester curing agent include, for example, bisphenol A dicyanate, polyphenol cyanate (oligo (3-methylene-1,5-phenylene cyanate), 4,4′-methylenebis (2,6-dimethylphenyl cyanate), 4,4′-ethylidenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanatephenylmethane), bis (4-cyanate-3, Bifunctional cyanate resins such as 5-dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether , Phenol novolac, Examples thereof include polyfunctional cyanate resins derived from resole novolac, dicyclopentadiene structure-containing phenol resins, prepolymers in which these cyanate resins are partially triazines, and these may be used alone or in combination of two or more. Examples of commercially available cyanate ester resins include phenol novolac polyfunctional cyanate ester resins (manufactured by Lonza Japan Co., Ltd., PT30, cyanate equivalent 124), and some or all of bisphenol A dicyanate are triazines and trimers. The prepolymer (Lonza Japan Co., Ltd. product, BA230, cyanate equivalent 232), dicyclopentadiene structure containing cyanate ester resin (Lonza Japan Co., Ltd. product, DT-4000, DT-7000) etc. are mentioned.

The mixing ratio of the epoxy resin and the curing agent is preferably a ratio in which the number of reactive groups of the curing agent is in the range of 0.3 to 2.0 when the number of epoxy groups of the epoxy resin is 1, preferably 0.4 to 1.1. The ratio which becomes a range is more preferable. The number of epoxy groups of the epoxy resin present in the thermosetting resin composition is a value obtained by dividing the solid content mass of each epoxy resin by the epoxy equivalent for all epoxy resins, and the number of reactive groups of the curing agent. Is a value obtained by adding the values obtained by dividing the solid mass of each curing agent by the reactive group equivalent for all curing agents.

Examples of the inorganic filler used in the present invention include silica, alumina, mica, mica, silicate, barium sulfate, magnesium hydroxide, titanium oxide, and the like. Silica and alumina are preferable, particularly amorphous silica, molten Silica such as silica, crystalline silica, synthetic silica, hollow silica and spherical silica is preferred, and spherical silica and fused silica are more preferred. These can use 1 type (s) or 2 or more types. From the viewpoint of improving the filling property to the thermosetting resin composition, spherical fused silica is more preferable. Examples of commercially available spherical fused silica include “SOC2” and “SOC1” manufactured by Admatechs.

The average particle size of the inorganic filler is preferably 2 μm or less, more preferably 1 μm or less, still more preferably 0.8 μm or less, and even more preferably 0.6 μm or less, from the viewpoint of improving insulation reliability and surface smoothness. On the other hand, the average particle size of the inorganic filler is preferably 0.01 μm or more, more preferably 0.05 μm or more, and further preferably 0.1 μm or more from the viewpoint of improving the dispersibility of the inorganic filler. The average particle diameter of the inorganic filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be prepared on a volume basis by a laser diffraction / scattering particle size distribution measuring apparatus, and the median diameter can be measured as the average particle diameter. As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As a laser diffraction scattering type particle size distribution measuring apparatus, LA-950 manufactured by Horiba, Ltd. or the like can be used.

  The content of the inorganic filler is 100% by mass of the non-volatile component in the thermosetting resin composition from the viewpoint of preventing the flexibility of the sheet form from decreasing and reducing the linear thermal expansion coefficient. In the case, 30 to 90% by mass is preferable, and 40 to 80% by mass is more preferable. Since the thermosetting resin composition layer for forming a conductor layer may be disadvantageous for forming a conductor layer by plating if the content of the inorganic filler is too high, it is more preferably 30 to 80% by weight, more preferably It can be 30 to 75% by weight, more preferably 30 to 70% by weight. Although the thermosetting resin composition layer for embedding the inner layer circuit board tends to decrease in fluidity when the amount of the inorganic filler is increased, it is preferable that the content is high from the viewpoint of decreasing the linear thermal expansion coefficient. It is desirable to ensure fluidity by blending a resin component having high fluidity. In the thermosetting resin composition layer for embedding the inner circuit board, the blending amount of the inorganic filler is preferably 40 to 90% by mass, more preferably 50 to 90% by mass, more preferably 60 to 90% by mass. Can do.

The inorganic filler is surface-treated with a surface treatment agent such as an epoxy silane coupling agent, an amino silane coupling agent, a mercapto silane coupling agent, a silane coupling agent, an organosilazane compound, or a titanate coupling agent. What improved the moisture resistance is preferable. You may use these 1 type or in combination of 2 or more types. Of these, aminosilane coupling agents are preferred because of their excellent moisture resistance, dispersibility, and properties of cured products. The surface treatment of the inorganic filler may be performed directly on the thermosetting resin composition before mixing, or the inorganic filler and the surface treatment agent are added to the thermosetting resin composition by the integral blend method. May be. Commercially available surface treatment agents include “KBM403” (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. and “KBM803” (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. "KBE903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., Shin-Etsu Chemical Co., Ltd. ) “KBM103” (phenyltrimethoxysilane), “SZ-31” (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd., and the like.

The thermosetting resin composition in the present invention can be directly blended with a coupling agent such as a silane coupling agent in the thermosetting resin composition for the purpose of improving the adhesion to the heat-resistant film. . Preferable silane coupling agents include those similar to those used for the surface treatment of the above-mentioned inorganic filler. When the surface treatment of the inorganic filler is performed by the integral blend method, the amount of the coupling agent to be blended can be adjusted as appropriate to set conditions suitable for the adhesion between the thermosetting resin composition and the heat-resistant film. .

The blending amount of the silane coupling agent is preferably 0.01% by weight or more and 5% by weight or less, and more preferably 0.1% by weight or more and 3% by weight or less with respect to the idle filler. If the amount of the silane coupling agent is less than this range, the adhesion to the heat-resistant film tends to decrease, and if it is large, the viscosity of the varnish when forming the thermosetting resin composition layer tends to increase too much. is there.

  The thermosetting resin composition in the present invention may contain a thermoplastic resin for the purpose of treating the surface with an oxidizing agent after curing to form an appropriate rough surface, or imparting film formability. Examples of the thermoplastic resin include phenoxy resin, polyvinyl acetal resin, polyimide resin, polyamideimide resin, polyethersulfone resin, and polysulfone resin, and phenoxy resin and polyvinyl acetal resin are preferable. A thermoplastic resin may be used individually by 1 type, or may use 2 or more types together.

  The polystyrene-reduced weight average molecular weight of the thermoplastic resin is preferably in the range of 8000 to 70000, more preferably in the range of 10,000 to 60000, and still more preferably in the range of 20000 to 60000. The weight average molecular weight in terms of polystyrene of the thermoplastic resin is measured by a gel permeation chromatography (GPC) method. Specifically, the polystyrene-reduced weight average molecular weight of the thermoplastic resin is LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P / K- manufactured by Showa Denko KK as a column. 804L / K-804L can be measured at a column temperature of 40 ° C. using chloroform or the like as a mobile phase, and can be calculated using a standard polystyrene calibration curve.

  Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene Examples thereof include phenoxy resins having a skeleton and one or more skeletons selected from the group consisting of a trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. A phenoxy resin may be used individually by 1 type, or may use 2 or more types together. Specific examples of the phenoxy resin include “1256” and “4250” (both bisphenol A skeleton-containing phenoxy resin), “YX8100” (bisphenol S skeleton-containing phenoxy resin), and “YX6954” (manufactured by Mitsubishi Chemical Corporation). In addition, “FX280” and “FX293” manufactured by Toto Kasei Co., Ltd., “YL7553”, “YL6794”, “YL7213” manufactured by Mitsubishi Chemical Corporation, YL7290 "," YL7482 ", etc. are mentioned.

  Specific examples of the polyvinyl acetal resin include: Electric Butyral 4000-2, 5000-A, 6000-C, 6000-EP manufactured by Denki Kagaku Kogyo Co., Ltd., S-Lec BH Series, BX Series manufactured by Sekisui Chemical Co., Ltd. KS series, BL series, BM series, etc. are mentioned.

  The content of the thermoplastic resin is preferably 0.5 to 60% by mass, more preferably 3 to 50% by mass, and 5 to 40% by mass with respect to 100% by mass of the non-volatile component in the thermosetting resin composition. Further preferred.

The thermosetting resin composition in the present invention may contain a curing accelerator for the purpose of improving curability. Examples of the curing accelerator include organic phosphine compounds, imidazole compounds, amine adduct compounds, and tertiary amine compounds. The content of the curing accelerator is preferably used in the range of 0.01 to 3% by mass when the total of the nonvolatile components of the epoxy resin and the curing agent is 100% by mass. A hardening accelerator may be used individually by 1 type, or may use 2 or more types together.

The thermosetting resin composition in the present invention may contain rubber particles for the purpose of treating the surface with an oxidizing agent after curing to form an appropriate rough surface. In particular, it is preferably contained in a thermosetting resin composition layer for forming a conductor layer. For example, the rubber particles are not dissolved in an organic solvent used when preparing the varnish of the thermosetting resin composition, and are not compatible with an essential component such as a cyanate ester resin or an epoxy resin. Accordingly, the rubber particles exist in a dispersed state in the varnish of the thermosetting resin composition of the present invention. Such rubber particles are generally prepared by increasing the molecular weight of the rubber component to a level at which it does not dissolve in an organic solvent or resin and making it into particles.

Preferable examples of rubber particles that can be used in the thermosetting thermosetting resin composition include core-shell type rubber particles, cross-linked acrylonitrile butadiene rubber particles, cross-linked styrene butadiene rubber particles, and acrylic rubber particles. The core-shell type rubber particles are rubber particles having a core layer and a shell layer. For example, a two-layer structure in which an outer shell layer is made of a glassy polymer and an inner core layer is made of a rubbery polymer, or Examples include a three-layer structure in which the outer shell layer is made of a glassy polymer, the intermediate layer is made of a rubbery polymer, and the core layer is made of a glassy polymer. The glassy polymer layer is made of, for example, a polymer of methyl methacrylate, and the rubbery polymer layer is made of, for example, a butyl acrylate polymer (butyl rubber). Two or more rubber particles may be used in combination. Specific examples of the core-shell type rubber particles include Staphyloid AC3832, AC3816N, IM-401 modified 1, IM-401 modified 7-17 (trade name, manufactured by Ganz Kasei Co., Ltd.), Metabrene KW-4426 (trade name, Mitsubishi) Rayon Co., Ltd.). Specific examples of the crosslinked acrylonitrile butadiene rubber (NBR) particles include XER-91 (average particle size: 0.5 μm, manufactured by JSR Corporation). Specific examples of the crosslinked styrene butadiene rubber (SBR) particles include XSK-500 (average particle size 0.5 μm, manufactured by JSR Corporation). Specific examples of the acrylic rubber particles include Methbrene W300A (average particle size 0.1 μm) and W450A (average particle size 0.2 μm) (manufactured by Mitsubishi Rayon Co., Ltd.).

The average particle diameter of the rubber particles to be blended is preferably in the range of 0.005 to 1 μm, more preferably in the range of 0.2 to 0.6 μm. The average particle diameter of the rubber particles used in the present invention can be measured using a dynamic light scattering method. For example, rubber particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves, etc., and a particle size distribution of rubber particles is created on a mass basis using a concentrated particle size analyzer (FPAR-1000; manufactured by Otsuka Electronics Co., Ltd.). And it can measure by making the median diameter into an average particle diameter.

The content of the rubber particles is preferably 1 to 10% by mass and more preferably 2 to 5% by mass with respect to 100% by mass of the nonvolatile content in the thermosetting resin composition.

Since the thermosetting resin composition in the present invention is improved in flame retardancy, it may contain a flame retardant. Examples of the flame retardant include an organic phosphorus flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a silicone flame retardant, and a metal hydroxide. Examples of organic phosphorus flame retardants include phenanthrene-type phosphorus compounds such as HCA, HCA-HQ, and HCA-NQ manufactured by Sanko Co., Ltd., phosphorus-containing benzoxazine compounds such as HFB-2006M manufactured by Showa Polymer Co., Ltd., and Ajinomoto Reefos 30, 50, 65, 90, 110, Fine Techno Co., TPP, RPD, BAPP, CPD, TCP, TXP, TBP, TOP, KP140, TIBP, TPPO, PPQ, manufactured by Hokuko Chemical Co., Ltd. Phosphoric ester compounds such as OP930 manufactured by Clariant Co., Ltd., PX200 manufactured by Daihachi Chemical Co., Ltd., and organic nitrogen-containing phosphorus compounds include phosphoric ester amides such as SP670 and SP703 manufactured by Shikoku Kasei Kogyo Co., Ltd. Compounds such as SPB100, SPE100 manufactured by Otsuka Chemical Co., Ltd., FP-series manufactured by Fushimi Pharmaceutical Co., Ltd. Sufazen compounds. As the metal hydroxide, magnesium hydroxide such as UD65, UD650, UD653 manufactured by Ube Materials Co., Ltd., B-30, B-325, B-315, B-308 manufactured by Sakai Kogyo Co., Ltd. Examples thereof include aluminum hydroxide such as B-303 and UFH-20.

In the thermosetting resin composition in the present invention, other components can be blended as necessary within a range not inhibiting the effects of the present invention. Other components include vinyl benzyl compounds, acrylic compounds, maleimide compounds, thermosetting resins such as blocked isocyanate compounds, organic fillers such as silicon powder, nylon powder and fluorine powder, thickeners such as Orben and Benton, Silicone-based, fluorine-based, polymer-based antifoaming or leveling agents, imidazole-based, thiazole-based, triazole-based, silane-based coupling agents, etc., phthalocyanine blue, phthalocyanine green, iodin green, Examples thereof include colorants such as disazo yellow and carbon black.

The thermosetting resin composition of the present invention is appropriately mixed with the above components, and if necessary, by kneading means such as a triple roll, ball mill, bead mill, sand mill, or stirring means such as a super mixer or planetary mixer. It can be produced as a resin varnish by kneading or mixing.

When the insulating resin sheet of the present invention is used for forming an interlayer insulating layer of a multilayer printed wiring board, etc., one of the thermosetting resin composition layers formed on both surfaces of the heat-resistant film is a thermosetting resin composition for forming a conductor layer. The other is a thermosetting resin composition layer for laminating an inner circuit board. In this case, the thickness of the thermosetting resin composition layer for forming the conductor layer is preferably 2 μm or more and 18 μm or less from the viewpoint of making the multilayer printed wiring board thinner, surface smoothness, plating formation and insulation. The lower limit is more preferably 3 μm or more, and further preferably 4 μm or more. The upper limit is preferably 16 μm or less, more preferably 14 μm or less, still more preferably 12 μm or less, still more preferably 10 μm or less, and even more preferably 8 μm or less. The thickness of the thermosetting resin composition layer for laminating the inner circuit board is preferably 10 μm or more and 120 μm or less from the viewpoint of making the multilayer printed wiring board thinner, surface smoothness, circuit embedding property, and insulation. The lower limit is more preferably 15 μm or more. The upper limit is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 25 μm or less.

The minimum melt viscosity of the thermosetting resin composition layer for inner layer circuit board lamination is preferably controlled to be 100 to 19500 poise from the viewpoints of circuit embedding property and surface smoothness of the insulating layer. From the viewpoint of preventing air entrainment at the time of embedding, it is preferably 18000 poise or less, more preferably 15000 poise or less, still more preferably 10,000 poise or less, still more preferably 8000 poise or less, and even more preferably 5000 poise or less. From the viewpoint of preventing bleeding at the time of embedding, it is preferably 200 poise or more, more preferably 400 poise or more, still more preferably 600 poise or more, and even more preferably 800 or more.

Various methods can be used as a method for manufacturing the insulating resin sheet. For example, a thermosetting resin composition containing an organic solvent can be prepared, the thermosetting resin composition can be applied on a heat-resistant film, and a thermosetting resin composition layer can be formed by drying. Drying conditions are preferably 80 to 120 ° C. and 3 to 15 minutes.
Further, for example, a resin sheet having a thermosetting resin composition layer for forming a conductor layer by forming a thermosetting resin composition layer on a film that becomes a support different from the heat-resistant film, and an inner layer circuit The insulating resin sheet of the present invention can also be produced by laminating a resin sheet having a thermosetting resin composition layer for embedding a substrate individually or simultaneously on the surface of the heat-resistant film. In this case, the film used as the support can also function as a protective film as it is. When a thermosetting resin composition is formed on a heat-resistant film by lamination, the conditions are preferably a lamination temperature of 70 to 110 ° C., a lamination time of 5 to 30 seconds, and a lamination pressure of 1 to 10 kgf / cm ² .

  Examples of organic solvents used in preparing a resin varnish for a thermosetting resin composition include ketones such as acetone, methyl ethyl ketone, cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, carbitol Acetates such as acetate, cellosolves such as cellosolve and butylcellosolve, carbitols such as carbitol and butylcarbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. Amides, etc. can be mentioned. Two or more of these organic solvents can be used in combination.

  In the insulating resin sheet of the present invention, at least the outer surface of the thermosetting resin composition layer for forming the conductor layer is protected with a protective film from the viewpoint of preventing adhesion of dust and the like, and handling when used in the production of multilayer printed wiring boards. It is preferable. Preferably, both outer surfaces of the thermosetting resin composition layer are protected by protective films.

Examples of the protective film of the present invention include plastic films and metal foils. Specifically, as the plastic film, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyester such as polyethylene naphthalate, polycarbonate, acrylic, cyclic polyolefin, triacetyl cellulose, polyether sulfide, polyether ketone And polyimide. Among these, a polyethylene terephthalate film and a polyethylene naphthalate film are preferable, and an inexpensive polyethylene terephthalate film is particularly preferable. Examples of the metal foil include copper foil and aluminum foil. From the viewpoint of versatility, a plastic film is preferable, and when a plastic film is used, it is preferable to use a support body on which the surface of the resin layer is release-treated in order to improve the peelability. The release agent used for the release treatment is not particularly limited as long as the resin layer can be peeled off from the support. For example, silicone release agent, alkyd resin release agent, polyolefin resin, urethane resin, fluorine Examples thereof include resins. In addition, you may use the plastic film with a release layer marketed as a preferable thing, For example, SK-1, AL which is a PET film which has a release layer which has an alkyd resin type release agent as a main component, for example -5, AL-7 (manufactured by Lintec Corporation) and the like. Further, the plastic film may be subjected to mat treatment or corona treatment, and a release layer may be formed on the treated surface. On the other hand, the metal foil can be removed by an etching solution, but the metal foil may be used as a conductor layer without being removed. Although the thickness of a protective film is not specifically limited, The range of 3-150 micrometers is preferable and the range of 3-50 micrometers is more preferable.

In the insulating resin film of the present invention, the etching amount per unit area (E1) of the heat-resistant film and the etching amount per unit area of the thermosetting resin composition layer (E2) are E1 / E2 = 0.5-3. Adjust to the range. Preferably E1 / E2 = 0.5-2, more preferably E1 / E2 = 0.5-1.5, more preferably E1 / E2 = 0.7-1.3, more preferably E1 / E2 = 0 .8 to 1.2, more preferably 0.9 to 1.1. In the present invention, the etching amount of the thermosetting resin composition layer means the etching amount of the cured product after thermosetting the thermosetting resin composition layer.

  By adjusting the etching amount of each layer in this way, when an interlayer insulating layer of a multilayer printed wiring board is formed by an insulating resin sheet having a heat-resistant film layer, a via hole is formed in the insulating layer after that, and when desmear treatment is performed, It is possible to avoid a problem that a via step is generated between the heat-resistant film layer and the thermosetting resin composition layer, the via shape is distorted, and the conduction reliability of the via hole is lowered. In particular, in the case of small-diameter via holes, the effect of via-shaped distortion becomes more obvious, so by using the configuration of the present invention, it is possible to produce a thin multilayer printed wiring board that has excellent mechanical strength and excellent via shape. It becomes possible. In the thermosetting resin composition layer formed on both sides of the heat-resistant film layer, the thermosetting resin composition layer for forming the conductor layer is different from the thermosetting resin composition layer for laminating the inner circuit board. When comprised from a composition, it is desirable to adjust the value of E1 and E2 in this range in each thermosetting resin composition layer.

  The means for adjusting the etching amount per unit area of each layer is not particularly limited. For example, the following method can be used. First, the etching amount of the heat resistant film layer is measured. Next, the amount of etching of the cured product layer obtained by curing the thermosetting resin composition layer is adjusted appropriately by adjusting the amount of the roughening component in the thermosetting resin composition, the type of epoxy resin, the type and blending amount of the curing agent. Thus, the relationship between the etching amounts of the respective layers is adjusted to fall within the above range. For example, the amount of etching generally tends to increase if the blending amount of a thermoplastic resin, rubber particles, or the like as a roughening component is increased. Moreover, if the compounding quantity of a liquid epoxy resin is increased as an epoxy resin, the etching amount generally tends to increase. If a phenol resin is used as a curing agent, the etching amount tends to increase, and if an active ester is used, it tends to decrease.

The measurement of the etching amount of the cured product of the thermosetting resin composition layer will be described. The curing conditions for actually producing a multilayer printed wiring board can be adopted as the curing conditions for obtaining a cured product by thermosetting the thermosetting resin composition layer. For example, it is preferably selected in the range of 150 to 220 ° C. for 20 to 180 minutes, more preferably 160 to 210 ° C. for 30 to 120 minutes. The cured product is cut into a certain area (for example, 10 cm × 10 cm) to obtain a test piece. For example, the test piece is dried at 130 ° C. for 15 minutes, and the mass immediately after drying (initial mass M1) is measured. Next, the test piece is subjected to desmear treatment, washed with water, dried under the same impression conditions (for example, at 130 ° C. for 15 minutes), and the mass immediately after drying (post-desmear mass M2) is measured. The etching amount per unit area of the cured product of the resin composition layer is measured by the following calculation formula. The etching amount per unit area of the heat-resistant film can also be measured in the same manner for the thermosetting resin composition layer except that there is no step of thermosetting.

Etching amount per unit area (g / m ² ) = (M1−M2) / surface area of cured product.

As the desmear condition for measuring the etching amount, the desmear condition for actually manufacturing a multilayer printed wiring board can be adopted. For example, the test piece is dipped in swelling dip / seculigand P containing diethylene glycol monobutyl ether of Atotech Japan Co., Ltd., which is a swelling liquid, at 60 ° C. for 5 minutes, and then the outlet of Atotech Japan Co., Ltd. as a roughening solution. Immerse in rate compact P (KMnO4: 60 g / L, NaOH: 40 g / L aqueous solution) at 80 ° C. for 20 minutes, and after washing with water, finally use as a neutralization solution, reduction reduction solution of Atotech Japan Co., Ltd. Immerse in securigant P at 40 ° C. for 5 minutes.

In the insulating resin film of the present invention, the difference between the linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film and the linear thermal expansion coefficient (C2) of 25 to 150 ° C. of the cured product of the thermosetting resin composition layer. The absolute value of is preferably 30 ppm / ° C. or less. 25 ppm / ° C. or less is more preferred, 20 ppm / ° C. or less is more preferred, and 15 ppm / ° C. or less is particularly preferred. If the absolute value of the difference in coefficient of linear thermal expansion exceeds 30 ppm / ° C., the step on the via sidewall tends to increase due to thermal history during via formation. The absolute value of the difference in linear thermal expansion coefficient can be adjusted by adjusting the linear thermal expansion coefficient of the thermosetting resin composition layer. For example, in order to lower the linear thermal expansion coefficient of the cured product of the thermosetting resin composition layer, the epoxy resin is rigid such as naphthol type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin and naphthylene ether type epoxy resin. Adopting an epoxy resin with a simple structure, increasing the compounding amount of inorganic fillers such as silica, and the amount of components that tend to increase the coefficient of linear thermal expansion, such as liquid epoxy resins, thermoplastic resins, rubber particles, etc. It can be adjusted by appropriately combining blending components such as setting it low.

Hereinafter, an example of the manufacturing method of the multilayer printed wiring board using the insulating resin sheet of this invention is explained in full detail.

In the method for producing a multilayer printed wiring board according to the present invention, (A) the insulating resin sheet has the thermosetting resin composition layer for laminating the inner layer circuit board as the inner layer circuit board side, and one or both sides of the inner layer circuit board. (B) Step of thermosetting the thermosetting resin composition layer of the insulating resin sheet to form an insulating layer, (C) Step of peeling the protective film, (D) Drilling into the insulating layer A step of forming via holes, (E) a step of roughening the surface of the insulating layer (thermosetting resin composition layer for forming a conductor layer), (F) a conductor by plating the surface of the insulating layer after the roughening treatment Forming a layer, and the like.

(A) In the step of laminating the insulating resin sheet on one side or both sides of the inner layer circuit board (step (A)), the thermosetting resin composition layer for laminating the inner layer circuit board of the insulating resin sheet is set to the inner layer circuit board side. And laminated on one or both sides of the inner circuit board. As used herein, the inner layer circuit board refers to a conductive layer patterned (circuit formed) on one or both sides of a glass epoxy board, a metal board, a polyester board, a polyimide board, a BT resin board, or a thermosetting polyphenylene ether board. And an intermediate product in which an insulating layer and a conductor layer are to be formed when a multilayer printed wiring board is manufactured. In addition, it is preferable from the viewpoint of improving the adhesion between the insulating layer and the inner circuit board that the surface of the conductor layer has been previously roughened by blackening or the like.

   In step (A), when the insulating resin sheet has a protective film, after removing the protective film, the insulating resin sheet and the inner circuit board are preheated as necessary, and the insulating resin sheet is pressurized and Crimp to the inner circuit board while heating. In the insulating resin sheet of the present invention, a method of laminating on a circuit board under reduced pressure by a vacuum laminating method is suitably used. Lamination conditions are not particularly limited. For example, the pressure bonding temperature (laminating temperature) is preferably 70 to 140 ° C., and the pressure bonding pressure (laminating pressure) is preferably 1 to 11 kgf / cm 2 (9.8 × 104). ˜107.9 × 10 4 N / m 2), the pressure bonding time (laminating time) is preferably 5 to 180 seconds, and the lamination is preferably performed under reduced pressure with an air pressure of 20 mmHg (26.7 hPa) or less. The laminating method may be a batch method or a continuous method using a roll. The vacuum lamination can be performed using a commercially available vacuum laminator. Commercially available vacuum laminators include, for example, a vacuum applicator manufactured by Nichigo-Morton Co., Ltd., a vacuum pressurizing laminator manufactured by Meiki Seisakusho Co., Ltd., a roll dry coater manufactured by Hitachi Industries, Ltd., and Hitachi AIC Co., Ltd. ) Made vacuum laminator and the like.

(B) In the step of thermosetting the insulating resin sheet to form the insulating layer (step (B)), the insulating resin sheet is laminated on the inner layer circuit board, and then the thermosetting resin composition layer is thermoset. An insulating layer (cured product) can be formed on the inner layer circuit board. The thermosetting conditions may be appropriately selected according to the type and content of the resin component in the resin composition, but preferably 150 ° C. to 220 ° C. for 20 minutes to 180 minutes, more preferably 160 ° C. to 210 ° C. It is selected in the range of 30 to 120 minutes at ° C. Further, by thermosetting without peeling off the support, it is possible to prevent adhesion of foreign matters such as dust and dust during thermosetting.

(C) In the step of peeling the protective film (step (C)), the protective film is peeled off. When the substrate is a plastic film, the substrate can be peeled by mechanical removal with a manual or automatic peeling device. When the substrate is a metal foil, the metal foil can be peeled and removed by dissolving the metal foil with an etching solution or the like.

(D) In the step of forming a via hole by drilling the insulating layer (step (D)), the via hole is formed by drilling the insulating layer. The drilling can be performed by a known method such as drilling, laser, or plasma, or a combination of these methods if necessary. However, drilling by a laser such as a carbon dioxide laser or YAG laser is preferable and versatile. In view of the above, a carbon dioxide laser is more preferable. In addition, (D) process may be performed before (C) process, and may be performed after (C) process.

When forming a via hole with a carbon dioxide laser, the number of shots is usually selected from 1 to 5 shots, although it depends on the depth and hole diameter of the via hole to be formed. In order to increase the processing speed of the via hole and improve the productivity of the multilayer printed wiring board, it is better that the number of shots is small, and the number of shots is preferably 1 to 3. In addition, when processing with multiple shots, the burst mode, which is a continuous shot, is a multi-shot with a time interval because the processing heat is trapped in the hole and the via shape tends to be distorted. Is preferred.

The pulse width of the carbon dioxide laser is not particularly limited, and can be selected in a wide range from a middle range of 28 μsec to a short pulse of 4 μsec. However, in the case of high energy, the short pulse is superior in the via processing shape.

When drilling with a carbon dioxide laser, in the insulating resin sheet of the present invention, the laser energy is adjusted to 1 to 6 mJ from the viewpoint of suppressing the step between the first layer and the second layer and improving the via shape. It is preferable to adjust to 2 to 5 mJ.

The opening diameter of the via hole is preferably 100 μm or less, more preferably 75 μm or less, and even more preferably 50 μm or less from the viewpoint of reducing the size of electronic devices. When the opening diameter of the via hole is reduced, generally the influence of the via hole shape distortion on the via conduction reliability becomes remarkable, but in the present invention, the via shape can be kept good even in the via hole having a small opening diameter. .

(E) In the step of roughening the surface of the insulating layer (step (E)), the surface of the insulating layer is roughened after the protective film is peeled off. In the case of dry-type roughening treatment, plasma treatment and the like can be mentioned, and in the case of wet-type roughening treatment, a swelling treatment with a swelling liquid, a roughening treatment with an oxidizing agent, and a neutralization treatment with a neutralizing liquid are performed in this order. It is done. The wet roughening treatment is preferable in that smear in the via hole can be removed while forming an uneven anchor on the surface of the insulating layer.

The swelling treatment with the swelling liquid is performed by immersing the insulating layer in the swelling liquid at 50 to 80 ° C. for 5 to 20 minutes (preferably at 55 to 70 ° C. for 8 to 15 minutes). Examples of the swelling liquid include an alkaline solution and a surfactant solution, and an alkaline solution is preferable. Examples of the alkaline solution include a sodium hydroxide solution and a potassium hydroxide solution. Examples of the commercially available swelling liquid include Swelling Dip Securiganth P (Swelling Dip Securiganth P) and Swelling Dip Securiganth SBU (ABUTEC Japan). be able to. Moreover, the via | veer shape can be maintained more favorable by performing a swelling process, performing a washing process after that, and performing the roughening process by an oxidizing agent after that.

The roughening treatment with an oxidizing agent is performed by immersing the insulating layer in an oxidizing agent solution at 60 to 80 ° C. for 10 to 30 minutes (preferably at 70 to 80 ° C. for 15 to 25 minutes). Examples of the oxidizing agent include alkaline permanganate solution in which potassium permanganate and sodium permanganate are dissolved in an aqueous solution of sodium hydroxide, dichromate, ozone, hydrogen peroxide / sulfuric acid, nitric acid and the like. it can. The concentration of permanganate in the alkaline permanganate solution is preferably 5 to 10% by weight. Examples of commercially available oxidizing agents include alkaline permanganic acid solutions such as Concentrate Compact CP and Dosing Solution Securigans P manufactured by Atotech Japan.

The neutralization treatment with the neutralizing solution is performed by immersing in a neutralizing solution at 30 to 50 ° C. for 3 to 10 minutes (preferably at 35 to 45 ° C. for 3 to 8 minutes). As the neutralizing solution, an acidic aqueous solution is preferable, and as a commercially available product, Reduction Solution / Secligant P manufactured by Atotech Japan Co., Ltd. may be mentioned.

(F) In the step of plating the surface of the insulating layer after the roughening treatment to form a conductor layer ((F step)), the conductor layer can be formed on the surface of the insulating layer. As a method for forming the plating, a conductor layer may be formed on the insulating layer by dry plating or wet plating. As the dry plating, a known method such as vapor deposition, sputtering, or ion plating can be used. As wet plating, a method of forming a conductor layer by combining electroless plating and electrolytic plating after the roughening treatment, a method of forming a plating resist having a pattern opposite to that of the conductor layer, and forming the conductor layer only by electroless plating , Etc. As a subsequent pattern formation method, for example, a subtractive method or a semi-additive method known to those skilled in the art can be used.

By repeating the above-described series of steps a plurality of times, a multilayer printed wiring board in which build-up layers are laminated in multiple stages is obtained. In the present invention, since the conduction reliability between layers can be ensured by improving the via shape, it can be suitably used as an insulating resin sheet for a buildup layer of a multilayer printed wiring board.

A semiconductor device can be manufactured by using the multilayer printed wiring board manufactured by the method of the present invention. A semiconductor device can be manufactured by mounting a semiconductor chip in a conductive portion of the multilayer printed wiring board of the present invention. The “conduction location” is a “location where an electrical signal is transmitted in a multilayer printed wiring board”, and the location may be a surface or an embedded location. The semiconductor chip is not particularly limited as long as it is an electric circuit element made of a semiconductor.

The semiconductor chip mounting method for manufacturing the semiconductor device of the present invention is not particularly limited as long as the semiconductor chip functions effectively, but specifically, a wire bonding mounting method, a flip chip mounting method, and no bumps. Examples include a mounting method using a build-up layer (BBUL), a mounting method using an anisotropic conductive film (ACF), and a mounting method using a non-conductive film (NCF).

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example. In the following description, “part” means “part by mass”.

First, measurement methods and evaluation methods in the physical property evaluation in this specification will be described.

<Evaluation of via shape>
(1) Substrate treatment glass cloth substrate epoxy resin double-sided copper-clad laminate [copper foil thickness 18 μm, substrate thickness 0.3 mm, Matsushita Electric Works Ltd. R5715ES] on both sides of MEC CZ8100 The copper surface was roughened by dipping.
(2) Lamination of insulating resin sheets The insulating resin sheets prepared in the examples and comparative examples were made using a batch type vacuum pressure laminator MVLP-500 (trade name, manufactured by Meiki Co., Ltd.), and the second layer was copper-clad. Lamination was performed so as to contact both sides of the laminate. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressure bonding for 30 seconds at 100 ° C. and a pressure of 0.74 MPa.
(3) After the resin composition was cured and laminated, the resin composition was cured at 100 ° C. for 30 minutes and then at 180 ° C. for 30 minutes to form an insulating layer.
(4) After forming and curing the via hole, the support was peeled off, and a via hole was formed on the first layer using a laser processing machine (a carbon dioxide laser device manufactured by Mitsubishi Electric Corporation: ML605GTWII-P). The conditions of laser irradiation were as follows: pulse width 13 μs, energy 3 mJ, number of shots 1 shot, mask diameter 1.1 mm.
(5) After forming the desmear treatment and roughening treatment via-hole, it is immersed for 5 minutes at 60 ° C. in a swelling dip seculigand P containing diethylene glycol monobutyl ether of Atotech Japan Co., Ltd. (swelling condition 1) or 10 Immerse in water for 2 minutes (swelling condition 2), then as a roughening solution, immerse in concentrate compact P (KMnO4: 60 g / L, NaOH: 40 g / L aqueous solution) of Atotech Japan for 10 minutes at 80 ° C ( Immersion condition 1) or 20 minutes immersion (immersion condition 2), and after washing with water, finally, as a neutralizing solution, immersion was carried out at 40 ° C. for 5 minutes in the reduction solution securigant P of Atotech Japan Co., Ltd. Then, it dried at 130 degreeC for 15 minutes. As a result, the surface of the insulating layer was roughened and the smear in the via hole was removed.
(6) Conductive layer formation by semi-additive method In order to form a conductive layer on the insulating layer surface and via hole, electroless copper plating (using an electroless copper plating process using Atotech Japan Co., Ltd. pharmaceutical solution) was performed. . The film thickness of the electroless copper plating was 1 μm. Thereafter, electrolytic copper plating was performed to form a conductor layer (copper layer) having a total thickness of 30 μm.

<Electroless copper plating process using Atotech Japan Co., Ltd. pharmaceutical solution>
1. Alkali cleaning (resin surface cleaning and charge adjustment)
Product Name: Cleaning cleaner Securiganth 902
Condition: 5 minutes at 60 ° C. Soft etching (via bottom, copper cleaning of conductor)
Sulfuric acid sodium peroxodisulfate aqueous solution
Condition: 1 minute at 30 ° C. Pre-dip (for the purpose of adjusting the surface charge for the next Pd application)
Product Name: Pre. Dip Neoganth B
Condition: 1 minute at room temperature Activator (addition of Pd to the resin surface)
Product Name: Activator Neoganth 834
Conditions: 5 minutes at 35 ° C. Reduction (reducing Pd attached to the resin)
Product Name: Reducer Neoganth WA
: Reducer Acceralator 810 mod. Mixed solution condition: 5 minutes at 30 ° C Electroless copper plating (Cu is deposited on the resin surface (Pd surface))
Product Name: Basic Solution Printganth MSK-DK
： Copper solution Printganth MSK
: Stabilizer Printganth MSK-DK
: Reducer Cu mixed solution condition: 20 minutes at 35 ° C

(7) Observation of via The cross section of the via was observed with an SEM. “○” if the wall surface step between the heat-resistant film and the resin composition layer (cured product) is less than 3 μm, “△” if the wall surface step is 3 μm or more and less than 5 μm, and “×” if the wall surface step is 5 μm or more. It was.

<Measurement of etching amount per unit area>
Adhesive film consisting of a thermosetting resin composition layer (upper layer) for forming a conductor layer and a thermosetting resin composition layer (lower layer) for laminating an inner circuit board (sandwich using hot rolls on both sides of a heat-resistant film) Before the adhesive film of the present invention is obtained, both sides of the glass cloth base epoxy resin double-sided copper-clad laminate [copper foil thickness 18 μm, substrate thickness 0.3 mm, Matsushita Electric Works R5715ES] Laminate on both sides of the substrate that was immersed in CZ8100 manufactured by Co., Ltd. and roughened the copper surface, then heat at 100 ° C for 30 minutes and then at 180 ° C for 30 minutes (same conditions as pre-cure before desmearing) Thus, a substrate having a cured product formed on both sides was obtained. Thereafter, it is cut into 10 cm squares, the support is peeled off, and dried at 130 ° C. for 15 minutes. The mass immediately after the drying (initial mass (X1)), and after the drying, further desmear treatment and water washing are performed at 15 ° C. for 15 minutes. The mass immediately after partial drying (mass after desmear (X2)) was measured, and the etching amount of each cured product was determined by the following formula. The “desmear process” here is the same process as the above-described desmear process.
Moreover, the etching amount of the heat resistant film alone was measured in the same way for the film alone.

Etching amount per unit area (g / m2) = (X1-X2) / surface area of cured product (or heat-resistant film)

<Measurement of minimum melt viscosity>
The melt viscosity of the thermosetting resin composition layer (lower layer) for inner layer circuit board lamination was measured. Using a model Rheosol-G3000 manufactured by UBM Co., Ltd., using a parallel plate having a resin amount of 1 g and a diameter of 18 mm, a starting temperature of 60 ° C. to 200 ° C., a heating rate of 5 ° C./min, The minimum melt viscosity (poise) was measured under the measurement conditions of a measurement temperature interval of 2.5 ° C., vibration of 1 Hz, and strain of 1 deg.

<Thickness measurement>
It measured using the resin composition layer (each upper layer and lower layer) of the insulating resin sheet used by the Example and the comparative example, and the contact-type layer thickness meter (Mitutoyo Co., Ltd. product, MCD-25MJ).

<Measurement of linear thermal expansion coefficient>
Each adhesive film and insulating resin sheet were cured at 180 ° C. for 90 minutes, and the cured product and each heat-resistant film peeled off from the release PET were cut into test pieces having a width of about 5 mm and a length of about 15 mm, and manufactured by Rigaku Corporation Thermomechanical analysis was performed in tensile mode using a mechanical analyzer Thermo plus TMA 8310. The measurement was performed twice at a load of 1 g and a heating rate of 5 ° C./min. The average linear expansion coefficient from 25 ° C. to 150 ° C. in the second measurement was defined as the thermal expansion coefficient.

<Manufacture example 1 of an adhesive film>
Bisphenol type epoxy resin (“ZX1059” manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent of about 169), 5 parts of crystalline bifunctional epoxy resin (Mitsubishi Chemical Corporation ) "YX4000HK", epoxy equivalent of about 185) 12 parts, dicyclopentadiene type epoxy resin (DIC Corporation "HP7200H", epoxy equivalent of about 275) 9 parts, phenoxy resin (Mitsubishi Chemical Corporation "YL7553BH30") 10 parts of MEK / cyclohexanone = 1/1 solution having a solid content of 30% by mass) was dissolved by heating in 30 parts of solvent naphtha with stirring. After cooling to room temperature, 40 parts of an active ester compound (“HPC8000-65T” manufactured by DIC Corporation, a toluene solution having a nonvolatile content of 65% by mass with an active group equivalent of about 223), a curing accelerator (4-dimethylamino) Spherical silica (average particle size 0.5 μm, surface treated with 3 parts of pyridine, 5 mass% MEK solution), phenylaminosilane coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) ) “SOC2” manufactured by Admatechs, 180 parts of carbon per unit surface area of 0.39 mg / m ² ) were mixed and dispersed uniformly with a high-speed rotating mixer to prepare a resin varnish.
Next, the resin composition layer after drying has a thickness of 15 μm (AL5) on the release surface of a polyethylene terephthalate film with a release treatment (“AL5” manufactured by Lintec Corporation, thickness 25 μm or 38 μm) (release PET). : 25 μm thickness) or 3 μm (AL5: 38 μm thickness), uniformly apply the resin varnish, and dry at 80 to 120 ° C. (average 100 ° C.) for 3 minutes (15 μm) and 2 minutes (3 μm) An adhesive film composed of the composition layer and release PET was prepared.

<Manufacture example 2 of an adhesive film>
Bisphenol type epoxy resin (“ZX1059” manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent of about 169), 8 parts, naphthalene type epoxy resin (manufactured by DIC Corporation “ "HP4032SS", epoxy equivalent of 144) 3 parts, crystalline bifunctional epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of approximately 185) 6 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC3000H") ”, 12 parts of an epoxy equivalent of about 288) and 10 parts of a phenoxy resin (“ E1256B40 ”manufactured by Mitsubishi Chemical Corporation, MEK solution having a solid content of 40 mass%) were dissolved in 15 parts of solvent naphtha with stirring. After cooling to room temperature, 12 parts of a triazine skeleton-containing phenolic curing agent (“LA-7054” manufactured by DIC Corporation, MEK solution having a solid content of 60% of hydroxyl group equivalent of 125), naphthalene type curing agent (Nippon Steel) Chemical "SN-485" hydroxyl equivalent 215 60% solid content MEK solution) 8 parts, curing accelerator (4-dimethylaminopyridine, solid content 5% by weight MEK solution) 0.5 parts, difficult Flame retardant (“HCA-HQ” manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphophenanthrene-10-oxide, average particle size 2 μm) 3 Part, spherical silica surface treated with a phenylaminosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM573”) (average particle size 0.5 μm, “SOC2” manufactured by Admatex Co., Ltd.), per unit surface area Carbon amount 0. 39 mg / m ² ) were mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish.
Next, in exactly the same manner as in Production Example 1, an adhesive film comprising a resin composition layer and release PET was produced.

<Manufacture example 3 of an adhesive film>
Bisphenol type epoxy resin (“ZX1059” manufactured by Nippon Steel Chemical Co., Ltd., 1: 1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent of about 169), 8 parts, naphthalene type epoxy resin (manufactured by DIC Corporation “ "HP4032SS", epoxy equivalent of 144) 3 parts, crystalline bifunctional epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of approximately 185) 6 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC3000H") ”, 12 parts of an epoxy equivalent of about 288) and 25 parts of phenoxy resin (“ E1256B40 ”manufactured by Mitsubishi Chemical Corporation, MEK solution having a solid content of 40% by mass) were dissolved in 15 parts of solvent naphtha with stirring. After cooling to room temperature, 12 parts of a triazine skeleton-containing phenolic curing agent (“LA-7054” manufactured by DIC Corporation, MEK solution having a solid content of 60% of hydroxyl group equivalent of 125), naphthalene type curing agent (Nippon Steel) Chemical "SN-485" hydroxyl equivalent 215 solid content 60% MEK solution) 8 parts, curing accelerator (4-dimethylaminopyridine, solid content 5% by mass MEK solution) 0.9 parts, difficult Flame retardant (“HCA-HQ” manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphophenanthrene-10-oxide, average particle size 2 μm) 3 Part, spherical silica surface treated with a phenylaminosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM573”) (average particle size 0.5 μm, “SOC2” manufactured by Admatex Co., Ltd.), per unit surface area Carbon amount 0. 39 parts of 39 mg / m ² ) were mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish.
Next, in exactly the same manner as in Production Example 1, an adhesive film comprising a resin composition layer and release PET was produced.

Using a hot roll, a support (38 μm release PET / resin composition 3 μm / heat-resistant film / resin composition 15 μm / support (25 μm release PET): heat-resistant film so that the structure is peeled off before lamination. An insulating resin sheet was manufactured by superimposing adhesive films from both sides of the film.The heat-resistant films include "BEXTER" (liquid crystal polymer film) manufactured by Kuraray Co., Ltd., "UPILEX-S" (polyimide) manufactured by Ube Industries, Ltd., “Pomilan T” manufactured by Arakawa Chemical Industries, Ltd. was used, and the evaluation results of each manufactured insulating resin sheet are shown in Table 1.

As shown in Comparative Examples 1 to 3 in Table 1, the insulating resin sheet having a ratio (E1 / E2) of the etching amount between the heat-resistant film layer and the resin composition layer of less than 0.5 or 3 or more is a via sidewall. The step is large. In Example 3, the etching amount ratio is an appropriate value, but the absolute value of the difference between the linear thermal expansion coefficients of the heat-resistant film layer and the resin composition layer exceeds 30, so that the step difference in the via sidewall increases. The phenomenon was seen.

In the present invention, when the insulating layer is formed, the mechanical strength can be improved, and the workability in forming the via hole is superior to that in the case of using the glass cloth, and the via shape distortion is also obtained in the small diameter via hole. Therefore, an insulating resin sheet capable of forming a favorable via hole can be provided. Furthermore, a multilayer printed wiring board and a semiconductor device using the same can be provided. Furthermore, electric products such as computers, mobile phones, digital cameras, and televisions, and vehicles such as motorcycles, automobiles, trains, ships, and airplanes equipped with these can be provided.

Claims (28)

  An insulating resin sheet having a heat resistant film and a thermosetting resin composition layer formed on both sides of the heat resistant film, the etching amount per unit area (E1) of the heat resistant film and the thermosetting resin composition The insulating resin sheet whose etching amount per unit area (E2) of the hardened | cured material of a layer is E1 / E2 = 0.5-3.   The etching amount (E1) per unit area of the heat-resistant film and the etching amount (E2) per unit area of the cured product of the thermosetting resin composition layer are E1 / E2 = 0.5-2. The insulating resin sheet according to 1.   The etching amount (E1) per unit area of the heat-resistant film and the etching amount (E2) per unit area of the cured product of the thermosetting resin composition layer are E1 / E2 = 0.5 to 1.5. The insulating resin sheet according to claim 1.   The etching amount per unit area of the heat-resistant film (E1) and the etching amount per unit area of the cured product of the thermosetting resin composition layer (E2) are E1 / E2 = 0.7 to 1.3. The insulating resin sheet according to claim 1.   The absolute value of the difference between the linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film and the linear thermal expansion coefficient (C2) of 25 to 150 ° C. of the cured product of the thermosetting resin composition layer is 30 ppm / The insulating resin sheet according to any one of claims 1 to 4, wherein the insulating resin sheet has a temperature not higher than ° C.   The absolute value of the difference between the linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film and the linear thermal expansion coefficient (C2) of 25 to 150 ° C. of the cured product of the thermosetting resin composition layer is 25 ppm / The insulating resin sheet according to any one of claims 1 to 4, wherein the insulating resin sheet has a temperature not higher than ° C.   The absolute value of the difference between the linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat resistant film and the linear thermal expansion coefficient (C2) of 25 to 150 ° C. of the cured product of the thermosetting resin composition layer is 20 ppm / The insulating resin sheet according to any one of claims 1 to 4, wherein the insulating resin sheet has a temperature not higher than ° C.   The absolute value of the difference between the linear thermal expansion coefficient (C1) of 25 to 150 ° C. of the heat-resistant film and the linear thermal expansion coefficient (C2) of 25 to 150 ° C. of the cured product of the thermosetting resin composition layer is 15 ppm / The insulating resin sheet according to any one of claims 1 to 4, wherein the insulating resin sheet has a temperature not higher than ° C.   The insulating resin sheet according to any one of claims 1 to 8, wherein the heat-resistant film has a coefficient of linear thermal expansion (C1) of 25 to 150 ° C of 30 ppm / ° C or less.   The heat-resistant film is selected from the group consisting of a polyethylene naphthalate film, a polyphenylene sulfide film, a polyetheretherketone film, a polyimide film, a polyetherimide film, an aramid film, a polyamideimide film, and a liquid crystal polymer film. The insulating resin sheet according to any one of the above items.   The insulating resin sheet according to claim 1, wherein the heat-resistant film has a thickness of 2 μm or more and 30 μm or less.   The insulating resin sheet according to any one of claims 1 to 11, wherein the thermosetting resin composition layer contains an epoxy resin, a curing agent, and an inorganic filler.   The insulating resin sheet according to claim 12, wherein the epoxy resin comprises at least one selected from a naphthol type epoxy resin, a naphthalene type epoxy resin, a biphenyl type epoxy resin, and a naphthylene ether type epoxy resin.   The insulating resin sheet according to claim 12, wherein the content of the inorganic filler in the thermosetting resin composition layer is 30% by weight or more and 90% by weight or less.   The insulating resin sheet according to claim 12, wherein the content of the inorganic filler in the thermosetting resin composition layer is 40% by weight or more and 80% by weight or less.   The insulating resin sheet according to any one of claims 1 to 15, wherein the cured product of the thermosetting resin composition layer has a coefficient of linear thermal expansion at 25 to 150 ° C of 50 ppm / ° C or less.   The insulating resin sheet according to any one of claims 1 to 15, wherein the cured product of the thermosetting resin composition layer has a coefficient of linear thermal expansion of 25 to 150 ° C of 40 ppm / ° C or less.   The insulating resin sheet according to any one of claims 1 to 15, wherein the cured product of the thermosetting resin composition layer has a coefficient of linear thermal expansion at 25 to 150 ° C of 30 ppm / ° C or less.   The insulating resin sheet according to claim 1, which is for a buildup layer of a multilayer printed wiring board.   One of the thermosetting resin composition layers formed on both surfaces of the heat-resistant film is a thermosetting resin composition layer for forming a conductor layer, and the other is a thermosetting resin composition layer for laminating an inner circuit board. The thickness of the thermosetting resin composition layer for forming the conductor layer is 2 μm or more and 18 μm or less, and the thickness of the thermosetting resin composition layer for the inner circuit board laminate is 5 μm or more and 120 μm or less. Insulating resin sheet.   The insulating resin sheet according to claim 20, wherein a minimum melt viscosity of the thermosetting resin composition layer for laminating the inner layer circuit board is 100 poise or more and 5000 poise or less.   The insulating resin sheet according to any one of claims 19 to 21, which has a protective film on at least the outer surface of the thermosetting resin composition layer for forming a conductor layer. A method for producing a multilayer printed wiring board comprising the following steps (A) to (F);
(A) A step of laminating the insulating resin sheet according to claim 22 on one side or both sides of the inner layer circuit board, with the thermosetting resin composition layer for laminating the inner layer circuit board facing the inner layer circuit board,
(B) a step of thermosetting the thermosetting resin composition layer of the insulating resin sheet to form an insulating layer;
(C) a step of peeling off the protective film layer,
(D) forming a via hole by drilling the insulating layer;
(E) A step of roughening the surface of the insulating layer (thermosetting resin composition layer for forming a conductor layer),
(F) A step of plating the surface of the insulating layer after the roughening treatment to form a conductor layer. Multilayer printed wiring board having an insulating layer formed by an insulating resin sheet according to claim 1-21, wherein.   The multilayer printed wiring board according to claim 24, wherein an opening diameter of the via hole is 100 µm or less.   The multilayer printed wiring board according to claim 24, wherein an opening diameter of the via hole is 75 µm or less.   The multilayer printed wiring board according to claim 24, wherein an opening diameter of the via hole is 50 µm or less. A semiconductor device comprising the multilayer printed wiring board according to any one of claims 24 to 27 .