JP2022071490A - Method for manufacturing printed wiring board - Google Patents

Abstract

To provide a method for manufacturing a printed wiring board which enables formation of a small-diameter via hole, is excellent in smear removal property and suppresses occurrence of a haloing phenomenon.SOLUTION: A method for manufacturing a printed wiring board includes a step (A) of forming an opening in an insulating layer containing a cured product of a resin composition by laser, and a step (B) of subjecting the opening to sandblast treatment using abrasive grains, and forming a via hole, in this order.SELECTED DRAWING: Figure 3

Description

The present invention relates to a method for manufacturing a printed wiring board.

In recent years, in printed wiring boards, build-up layers have been made into multiple layers, and there is a demand for finer wiring and higher densities. The build-up layer is formed by a build-up method in which an insulating layer and a conductor layer are alternately stacked, and in a manufacturing method by the build-up method, the insulating layer is generally formed by thermosetting a resin composition. Is.

Many proposals for resin compositions suitable for forming an insulating layer of an inner layer circuit board have been made, including, for example, the resin composition described in Patent Document 1.

Japanese Unexamined Patent Publication No. 2017-59779

By the way, in manufacturing a printed wiring board, via holes may be formed in the insulating layer. The "via hole" usually refers to a hole that penetrates the insulating layer. As a method of forming a via hole, a method using a laser can be considered.

When a via hole is formed by a laser, a resin residue called smear may be formed in the via hole. In order to remove this smear, it is usual to perform a desmear treatment for removing the smear using a chemical solution after the formation of the via hole by the laser. The present inventor has found that heat is generated when a laser is irradiated, and this heat is transferred to the base metal of the insulating layer and the inner layer circuit board to cause a haloing phenomenon. The haloing phenomenon means that peeling occurs between the insulating layer and the inner layer circuit board around the via hole. Such a haloing phenomenon usually occurs when the resin around the via hole is deteriorated by heat and the deteriorated portion is eroded by a chemical solution such as a roughening solution. The deteriorated portion is usually observed as a discolored portion.

Further, although a method of suppressing the haloing phenomenon by using sandblasting is conceivable, it is difficult to form a via hole having a small diameter by sandblasting, and the processing speed of the via hole may be slow.

The present invention has been made in view of the above circumstances, and by providing a method for manufacturing a printed wiring board capable of forming a via hole having a small diameter, having excellent smear removal property, and suppressing the occurrence of a haloing phenomenon. be.

As a result of diligent studies to solve the above-mentioned problems, the present inventor has found that by forming an opening by a laser and then forming a via hole by sandblasting, the smear removal property is excellent and the haloing phenomenon can be suppressed. , The present invention has been completed.

That is, the present invention includes the following contents.
[1] (A) a step of forming an opening in an insulating layer containing a cured product of a resin composition by a laser, and (B) a step of sandblasting the opening with abrasive grains to form a via hole. A method of manufacturing a printed wiring board, including in this order.
[2] The method for manufacturing a printed wiring board according to [1], wherein the average particle size of the abrasive grains is 10 μm or less.
[3] The method for manufacturing a printed wiring board according to [1] or [2], wherein the depth of the opening is 50% or more and 95% or less of the thickness of the insulating layer.
[4] The step (B) is a step of forming a via hole by colliding the abrasive grains with the bottom surface of the opening through the mask.
The printed wiring according to any one of [1] to [3], wherein the ratio (total value / opening diameter) of the total value of the thickness of the mask and the depth of the opening to the opening diameter of the via hole is 3 or less. How to make a board.
[5] The method for manufacturing a printed wiring board according to any one of [1] to [4], wherein the elastic modulus of the insulating layer at 23 ° C. is 0.1 GPa or more.
[6] The method for producing a printed wiring board according to any one of [1] to [5], wherein the resin composition contains an inorganic filler.
[7] The method for manufacturing a printed wiring board according to [6], wherein the content of the inorganic filler is 20% by mass or more when the non-volatile component in the resin composition is 100% by mass.
[8] The method for producing a printed wiring board according to any one of [1] to [7], wherein the resin composition contains a curable resin.
[9] The method for manufacturing a printed wiring board according to [8], wherein the content of the curable resin is 10% by mass or more when the non-volatile component in the resin composition is 100% by mass.
[10] The method for producing a printed wiring board according to [8] or [9], wherein the curable resin contains an epoxy resin and a curing agent.
[11] The method for producing a printed wiring board according to [10], wherein the curing agent is at least one selected from a phenol-based resin, an active ester-based resin, and a cyanate ester-based resin.
[12] The method for manufacturing a printed wiring board according to any one of [1] to [11], wherein the laser is a CO ₂ laser or a UV-YAG laser.

According to the present invention, it is possible to provide a method for manufacturing a printed wiring board capable of forming a via hole having a small diameter, having excellent smear removal property, and suppressing the occurrence of a haloing phenomenon.

FIG. 1 is a schematic cross-sectional view showing an example of a state in which an insulating layer and a support are formed on the main surface of an inner layer circuit board. FIG. 2 is a schematic cross-sectional view showing an example of the state after performing the step (A). FIG. 3 is a schematic cross-sectional view showing an example of the state after performing the step (B). FIG. 4 is a plan view schematically showing an insulating layer immediately before forming a conductor layer of a printed wiring board in which a via hole is formed by conventional laser processing. FIG. 5 is a cross-sectional view schematically showing an insulating layer immediately before forming a conductor layer of a printed wiring board in which a via hole is formed by conventional laser processing. FIG. 6 is a schematic cross-sectional view showing an example of a state in which an insulating layer and a metal foil are formed on the main surface of an inner layer circuit board. FIG. 7 is a schematic cross-sectional view showing an example of a state after the metal foil is subjected to the pattern etching process. FIG. 8 is a schematic cross-sectional view showing an example of the state after performing the step (A). FIG. 9 is a schematic cross-sectional view showing an example of the state after performing the step (B). FIG. 10 is a schematic cross-sectional view showing an example of the state after forming the filled via. FIG. 11 is a schematic cross-sectional view showing an example of a state in which an insulating layer, a metal foil, and a dry film are formed on the main surface of an inner layer circuit board. FIG. 12 is a schematic cross-sectional view showing an example of the state after exposure and development. FIG. 13 is a schematic cross-sectional view showing an example of the state after performing the step (A). FIG. 14 is a schematic cross-sectional view showing an example of the state after performing the step (B). FIG. 15 is a schematic cross-sectional view showing an example of the state after forming the filled via. FIG. 16 is a schematic cross-sectional view showing an example of the state after removing the dry film. FIG. 17 is a schematic cross-sectional view showing an example of a state in which an insulating layer and a dry film are formed on the main surface of an inner layer circuit board. FIG. 18 is a schematic cross-sectional view showing an example of the state after exposure and development. FIG. 19 is a schematic cross-sectional view showing an example of the state after performing the step (A). FIG. 20 is a schematic cross-sectional view showing an example of the state after performing the step (B). FIG. 21 is a schematic cross-sectional view showing an example of the state after forming the filled via.

Hereinafter, the present invention will be described in detail with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples listed below, and may be arbitrarily modified and implemented without departing from the scope of claims of the present invention and the equivalent scope thereof.

Before explaining the manufacturing method of the printed wiring board of the present invention in detail, the "resin composition" and the "resin sheet with a support" used in the manufacturing method of the printed wiring board of the present invention will be described.

[Resin composition]
The resin composition used for forming the cured product may have an insulating layer, which is the cured product, having sufficient hardness and insulating properties. In one embodiment, the resin composition comprises (a) an inorganic filler. The resin composition further contains (b) a curable resin, (c) a curing accelerator, (d) a thermoplastic resin, (e) an elastomer, and (f) other additives, if necessary. May be good. Hereinafter, each component contained in the resin composition will be described in detail.

<(A) Inorganic filler>
The resin composition contains (a) an inorganic filler. An inorganic compound is used as the material of the inorganic filler. Examples of materials for inorganic fillers are silica, alumina, aluminosilicate, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, water. Aluminum oxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide , Zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, zirconium tungstate phosphate and the like. Among these, calcium carbonate and silica are preferable, and silica is particularly preferable. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica and the like. Further, as silica, spherical silica is preferable. (A) The inorganic filler may be used alone or in combination of two or more.

Examples of commercially available components (a) include "UFP-30" and "ASFP-20" manufactured by Denka Co., Ltd .; "SP60-05", "SP507-05" and "SPH516" manufactured by Nittetsu Chemical & Materials Co., Ltd. -05 ";" YC100C "," YA050C "," YA050C-MJE "," YA010C "manufactured by Admatex;" Silfil NSS-3N "," Silfil NSS-4N "," Silfil NSS-5N "manufactured by Tokuyama Corporation. "SC2500SQ", "SO-C4", "SO-C2", "SO-C1"; etc. manufactured by Admatex.

The specific surface area of the component (a) is preferably 1 m ² / g or more, more preferably 2 m ² / g or more, and particularly preferably 3 m ² / g or more. The upper limit is not particularly limited, but is preferably 60 m ² / g or less, 50 m ² / g or less, or 40 m ² / g or less. The specific surface area is obtained by adsorbing nitrogen gas on the sample surface using a specific surface area measuring device (Macsorb HM-1210 manufactured by Mountech) according to the BET method and calculating the specific surface area using the BET multipoint method. ..

The average particle size of the component (a) is preferably 0.01 μm or more, more preferably 0.05 μm or more, still more preferably 0.1 μm or more, and preferably 0.1 μm or more, from the viewpoint of remarkably obtaining the desired effect of the present invention. It is 5 μm or less, more preferably 2 μm or less, still more preferably 1 μm or less.

(A) The average particle size of the component can be measured by a laser diffraction / scattering method based on the Mie scattering theory. Specifically, it can be measured by creating a particle size distribution of the inorganic filler on a volume basis by a laser diffraction / scattering type particle size distribution measuring device and using the median diameter as the average particle size. As the measurement sample, 100 mg of an inorganic filler and 10 g of methyl ethyl ketone can be weighed in a vial and dispersed by ultrasonic waves for 10 minutes. The measurement sample was measured using a laser diffraction type particle size distribution measuring device, the light source wavelengths used were blue and red, and the volume-based particle size distribution of component (a) was measured by the flow cell method, and the obtained particle size distribution was obtained. The average particle size can be calculated as the median diameter from. Examples of the laser diffraction type particle size distribution measuring device include "LA-960" manufactured by HORIBA, Ltd.

The component (a) is preferably treated with a surface treatment agent from the viewpoint of enhancing moisture resistance and dispersibility. Examples of the surface treatment agent include vinylsilane-based coupling agents, (meth) acrylic-based coupling agents, fluorine-containing silane coupling agents, aminosilane-based coupling agents, epoxysilane-based coupling agents, and mercaptosilane-based coupling agents. Examples thereof include a silane-based coupling agent, an alkoxysilane, an organosilazane compound, and a titanate-based coupling agent. Of these, vinylsilane-based coupling agents, (meth) acrylic-based coupling agents, and aminosilane-based coupling agents are preferable, and aminosilane-based coupling agents are more preferable, from the viewpoint of remarkably obtaining the effects of the present invention. In addition, one type of surface treatment agent may be used alone, or two or more types may be used in any combination.

Examples of commercially available surface treatment agents include "KBM1003" (vinyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM503" (3-methacryloxypropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., and Shin-Etsu Chemical Co., Ltd. "KBM403" (3-glycidoxypropyltrimethoxysilane), "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., "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM103" (phenyl) manufactured by Shin-Etsu Chemical Co., Ltd. Trimethoxysilane), "KBM-4803" manufactured by Shin-Etsu Chemical Co., Ltd. (long-chain epoxy type silane coupling agent), "KBM-7103" manufactured by Shin-Etsu Chemical Co., Ltd. (3,3,3-trifluoropropyltrimethoxysilane) And so on.

The degree of surface treatment with the surface treatment agent is preferably within a predetermined range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 100 parts by mass of the inorganic filler is preferably surface-treated with 0.2 parts by mass to 5 parts by mass of a surface treatment agent, and is surface-treated with 0.2 parts by mass to 3 parts by mass. It is preferable that the surface is treated with 0.3 parts by mass to 2 parts by mass.

The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. The amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg / m ² or more, more preferably 0.1 mg / m ^{2 or more, and 0.2 mg / m 2 from} the viewpoint of improving the dispersibility of the inorganic filler. The above is more preferable. On the other hand, from the viewpoint of suppressing an increase in the melt viscosity of the resin varnish and the melt viscosity in the sheet form, 1 mg / m ² or less is preferable, 0.8 mg / m ² or less is more preferable, and 0.5 mg / m ² or less is further preferable. preferable.

The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (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 ultrasonic cleaning is performed at 25 ° C. for 5 minutes. After removing the supernatant and drying the solid content, 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, Ltd. or the like can be used.

The content (% by mass) of the component (a) is preferably 20% by mass or more, more preferably 30 when the non-volatile component in the resin composition is 100% by mass from the viewpoint of remarkably obtaining the effect of the present invention. It is mass% or more, more preferably 40% by mass or more, 50% by mass or more, preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less, 80% by mass or less. In the present invention, the content of each component in the resin composition is a value when the non-volatile component in the resin composition is 100% by mass, unless otherwise specified.

The content (% by volume) of the component (a) is preferably 10% by volume or more, more preferably 10% by volume, when the non-volatile component in the resin composition is 100% by volume from the viewpoint of remarkably obtaining the effect of the present invention. Is 30% by volume or more, more preferably 50% by volume or more, preferably 90% by volume or less, more preferably 85% by volume or less, still more preferably 80% by volume or less.

<(B) Curable resin>
The resin composition may contain (b) a curable resin. (B) As the curable resin, a curable resin that can be used when forming an insulating layer of a printed wiring board can be used, and a thermosetting resin is preferable.

Examples of the thermosetting resin include epoxy resin, phenol resin, naphthol resin, benzoxazine resin, active ester resin, cyanate ester resin, carbodiimide resin, amine resin, acid anhydride resin and the like. Can be mentioned. As the component (b), one type may be used alone, or two or more types may be used in combination at any ratio. Hereinafter, the resin composition reacts with an epoxy resin such as a phenol-based resin, a naphthol-based resin, a benzoxazine-based resin, an active ester-based resin, a cyanate ester-based resin, a carbodiimide-based resin, an amine-based resin, and an acid anhydride-based resin. Resins that can cure objects are sometimes collectively referred to as "hardeners". The resin composition preferably contains an epoxy resin and a curing agent as the component (b) from the viewpoint of lowering the dielectric loss tangent.

Examples of the epoxy resin as the component (b) include bixilenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, and dicyclopentadiene type epoxy resin. Trisphenol type epoxy resin, naphthol novolac type epoxy resin, phenol novolac 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, glycidylcyclohexane type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin having a butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring containing Examples thereof include an epoxy resin, a cyclohexane type epoxy resin, a cyclohexanedimethanol type epoxy resin, a naphthylene ether type epoxy resin, a trimethylol type epoxy resin, a tetraphenylethane type epoxy resin, and a phenolphthalimidine type epoxy resin. One type of epoxy resin may be used alone, or two or more types may be used in combination.

The resin composition preferably contains an epoxy resin having two or more epoxy groups in one molecule as the component (b). From the viewpoint of remarkably obtaining the desired effect of the present invention, the ratio of the epoxy resin having two or more epoxy groups in one molecule is preferably 50% by mass with respect to 100% by mass of the non-volatile component of the component (b). As mentioned above, it is more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

The epoxy resin may be a liquid epoxy resin at a temperature of 20 ° C. (hereinafter sometimes referred to as “liquid epoxy resin”) or a solid epoxy resin at a temperature of 20 ° C. (hereinafter referred to as “solid epoxy resin”). ). The resin composition may contain only the liquid epoxy resin as the component (b), may contain only the solid epoxy resin, or may contain a combination of the liquid epoxy resin and the solid epoxy resin. good.

As the liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferable.

Examples of the liquid epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenol novolac type epoxy resin, and ester skeleton. An alicyclic epoxy resin, a cyclohexane type epoxy resin, a cyclohexanedimethanol type epoxy resin, a glycidylamine type epoxy resin, and an epoxy resin having a butadiene structure, a glycidylcyclohexane type epoxy resin, and a phenolphthalimidine type epoxy resin are preferable. A type epoxy resin, glycidylcyclohexane type epoxy resin, and phenolphthalimidine type epoxy resin are more preferable.

Specific examples of the liquid epoxy resin include "HP4032", "HP4032D", and "HP4032SS" (naphthalene type epoxy resin) manufactured by DIC; "828US", "jER828EL", "825", and "Epicoat" manufactured by Mitsubishi Chemical Co., Ltd. 828EL "(bisphenol A type epoxy resin);" jER807 "," 1750 "(bisphenol F type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd .;" jER152 "(phenol novolak type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "630", "630LSD" (glycidylamine type epoxy resin); "ZX1059" manufactured by Nittetsu Chemical & Materials Co., Ltd. (mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin); manufactured by Nagase ChemteX. "EX-721" (glycidyl ester type epoxy resin); "Selokiside 2021P" (epoxy resin having an ester skeleton) manufactured by Daicel Co., Ltd .; "PB-3600" (epoxy resin having a butadiene structure) manufactured by Daicel Co., Ltd. Examples thereof include "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin) manufactured by Nittetsu Chemical & Materials Co., Ltd. These may be used individually by 1 type, or may be used in combination of 2 or more types.

As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in one molecule is preferable, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is more preferable.

Examples of the solid epoxy resin include bixilenol type epoxy resin, naphthalene type epoxy resin, naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, and biphenyl. Type epoxy resin, naphthylene ether type epoxy resin, anthracene type epoxy resin, bisphenol A type epoxy resin, bisphenol AF type epoxy resin, tetraphenylethane type epoxy resin are preferable, and biphenyl type epoxy resin, bixilenol type epoxy resin, tetraphenyl Etan type epoxy resin, naphthalene type epoxy resin, and naphthylene ether type epoxy resin are more preferable.

Examples of the solid epoxy resin include naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, and naphthylene ether type epoxy resin. Anthracene type epoxy resin, bisphenol A type epoxy resin, and tetraphenylethane type epoxy resin are preferable, and naphthalene type tetrafunctional epoxy resin, naphthol type epoxy resin, and biphenyl type epoxy resin are more preferable. Specific examples of the solid epoxy resin include "HP4032H" (naphthalene type epoxy resin), "HP-4700", "HP-4710" (naphthalen type tetrafunctional epoxy resin), and "N-690" manufactured by DIC. Cresol novolak type epoxy resin), "N-695" (cresol novolak type epoxy resin), "HP-7200", "HP-7200HH", "HP-7200H" (dicyclopentadiene type epoxy resin), "EXA-7311" , "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (naphthylene ether type epoxy resin); "EPPN-502H" manufactured by Nippon Kayaku Co., Ltd. ( Trisphenol type epoxy resin), "NC7000L" (naphthol novolac type epoxy resin), "NC3000H", "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin); "ESN475V" manufactured by Nittetsu Chemical & Materials Co., Ltd. (Naphthalene type epoxy resin), "ESN485" (naphthol novolac type epoxy resin); "YX4000H", "YL6121" (biphenyl type epoxy resin), "YX4000HK" (bixilenol type epoxy resin), " "YX8800" (anthracene type epoxy resin); "PG-100" and "CG-500" manufactured by Osaka Gas Chemical Co., Ltd., "YL7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd., "YL7800" (fluorene type epoxy resin) Resin), "jER1010" (solid bisphenol A type epoxy resin), "jER1031S" (tetraphenylethane type epoxy resin); "WHR-991S" (phenolphthalimidine type epoxy resin) manufactured by Nippon Kayaku Co., Ltd. Can be mentioned. These may be used alone or in combination of two or more.

(B) When a liquid epoxy resin and a solid epoxy resin are used in combination as a component, the amount ratio (liquid epoxy resin: solid epoxy resin) thereof is a mass ratio, preferably 1: 0.1 to 1: 1. 20, more preferably 1: 0.3 to 1:10, and particularly preferably 1: 0.5 to 1: 5. When the quantitative ratio of the liquid epoxy resin and the solid epoxy resin is in such a range, the desired effect of the present invention can be remarkably obtained. Further, usually, when used in the form of a resin sheet with a support, moderate adhesiveness is provided. Further, when used in the form of a resin sheet with a support, sufficient flexibility is usually obtained and handleability is improved. Further, usually, a cured product having sufficient breaking strength can be obtained.

(B) The epoxy equivalent of the epoxy resin as a component is preferably 50 g / eq. ~ 5000g / eq. , More preferably 50 g / eq. ~ 3000 g / eq. , More preferably 80 g / eq. ~ 2000g / eq. , Even more preferably 110 g / eq. ~ 1000 g / eq. Is. Within this range, a sufficiently cured product can be obtained with a sufficient cross-linking density of the cured product of the resin composition. Epoxy equivalent is the mass of an epoxy resin containing 1 equivalent of an epoxy group. This epoxy equivalent can be measured according to JIS K7236.

(B) The weight average molecular weight (Mw) of the epoxy resin as a component is preferably 100 to 5000, more preferably 250 to 3000, still more preferably 400 to 1500, from the viewpoint of remarkably obtaining the desired effect of the present invention. be. The weight average molecular weight of the epoxy resin is a polystyrene-equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

The content of the epoxy resin as the component (b) is preferably 1% by mass when the non-volatile component in the resin composition is 100% by mass from the viewpoint of obtaining a cured product showing good mechanical strength and insulation reliability. As mentioned above, it is more preferably 3% by mass or more, still more preferably 5% by mass or more. The upper limit of the content of the epoxy resin is preferably 50% by mass or less, more preferably 45% by mass or less, and particularly preferably 40% by mass or less, from the viewpoint of remarkably obtaining the desired effect of the present invention.

As the active ester resin as the component (b), a resin having one or more active ester groups in one molecule can be used. Among them, the active ester-based resin has two or more ester groups with high reaction activity such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds in one molecule. Resin is preferred. The active ester-based resin 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-based resin obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester-based resin 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, pyromellitic acid and the like.

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, dihydroxybenzophenol, trihydroxybenzophenone, tetrahydroxybenzophenone, fluoroglucin, Examples thereof include benzenetriol, dicyclopentadiene-type diphenol compound, and phenol novolac. Here, the "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing two phenol molecules with one dicyclopentadiene molecule.

Preferred specific examples of the active ester-based resin include an active ester-based resin containing a dicyclopentadiene-type diphenol structure, an active ester-based resin containing a naphthalene structure, an active ester-based resin containing an acetylated product of phenol novolac, and a benzoyl of phenol novolac. Examples thereof include active ester-based resins containing compounds. Of these, an active ester resin containing a naphthalene structure and an active ester resin containing a dicyclopentadiene type diphenol structure are more preferable. The "dicyclopentadiene-type diphenol structure" represents a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

Commercially available products of the active ester resin include "EXB9451", "EXB9460", "EXB9460S", "HPC-8000-65T", and "HPC-8000H-" as active ester resins containing a dicyclopentadiene type diphenol structure. "65TM", "EXB-8000L-65TM" (manufactured by DIC); "EXB9416-70BK", "EXB-8150-65T" (manufactured by DIC) as an active ester resin containing a naphthalene structure; "DC808" (manufactured by Mitsubishi Chemical Co., Ltd.) as an active ester-based resin containing; "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.) as an active ester-based resin containing a benzoylated product of phenol novolac; "DC808" (manufactured by Mitsubishi Chemical Co., Ltd.); "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.), "YLH1030" (manufactured by Mitsubishi Chemical Co., Ltd.), "YLH1048" (manufactured by Mitsubishi Chemical Co., Ltd.) as active ester-based resins that are benzoylates of phenol novolac. ); Etc. can be mentioned.

As the phenolic resin and the naphthol resin as the component (b), those having a novolak structure are preferable from the viewpoint of heat resistance and water resistance. Further, from the viewpoint of adhesion to the conductor layer, a nitrogen-containing phenol-based curing agent is preferable, and a triazine skeleton-containing phenol-based resin is more preferable.

Specific examples of the phenolic resin and the naphthol resin include, for example, "MEH-7700", "MEH-7810", "MEH-7851" manufactured by Meiwa Kasei Co., Ltd., "NHN" and "CBN" manufactured by Nippon Kayaku Co., Ltd. , "GPH", "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN-495V", "SN375", "SN395" manufactured by Nittetsu Chemical & Materials Co., Ltd. , DIC Corporation "TD-2090", "LA-7052", "LA-7054", "LA-1356", "LA-3018-50P", "EXB-9500" and the like.

Specific examples of the benzoxazine-based resin (b) as a component include "JBZ-OD100" (benzoxazine ring equivalent 218), "JBZ-OP100D" (benzoxazine ring equivalent 218), and "ODA-" manufactured by JFE Chemical Co., Ltd. "BOZ" (benzoxazine ring equivalent 218); "Pd" (benzoxazine ring equivalent 217) manufactured by Shikoku Kasei Kogyo Co., Ltd .; "FA" (benzoxazine ring equivalent 217); "HFB2006M" manufactured by Showa Polymer Co., Ltd. (Benzoxazine ring equivalent 432) and the like.

Examples of the cyanate ester-based resin as the component (b) include bisphenol A dicyanate, polyphenol cyanate, oligo (3-methylene-1,5-phenylene cyanate), and 4,4'-methylenebis (2,6-dimethylphenylcyanate). ), 4,4'-Etilidenediphenyldisianate, Hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanatephenylmethane), bis (4-cyanate-) 3,5-Dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether, etc. Bifunctional cyanate resin; polyfunctional cyanate resin derived from phenol novolac, cresol novolak and the like; prepolymer in which these cyanate resins are partially triazined; and the like. Specific examples of the cyanate ester resin include "PT30", "PT30S" and "PT60" (phenol novolac type polyfunctional cyanate ester resin), "ULL-950S" (polyfunctional cyanate ester resin) manufactured by Ronza Japan. Examples thereof include "BA230", "BA230S75" (a prepolymer in which a part or all of bisphenol A dicyanate is triazined to form a trimer), "BADBy" (bisphenol A dicyanate) and the like.

Specific examples of the carbodiimide-based resin as the component (b) include carbodilite (registered trademark) V-03 (carbodiimide group equivalent: 216, V-05 (carbodiimide group equivalent: 216)) and V-07 (registered trademark) manufactured by Nisshinbo Chemical Co., Ltd. Carbodiimide group equivalent: 200); V-09 (carbodiimide group equivalent: 200); Stavaxol® P (carbodiimide group equivalent: 302) manufactured by Rheinchemy.

Examples of the amine-based resin as the component (b) include resins having one or more amino groups in one molecule, for example, aliphatic amines, polyether amines, alicyclic amines, and aromatics. Examples thereof include amines, and among them, aromatic amines are preferable from the viewpoint of exhibiting the desired effect of the present invention. As the amine-based resin, a primary amine or a secondary amine is preferable, and a primary amine is more preferable. Specific examples of the amine-based curing agent include 4,4'-methylenebis (2,6-dimethylaniline), diphenyldiaminosulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'. -Diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl- 4,4'-Diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis (3-amino-4-hydroxyphenyl) propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane Diamine, 2,2-bis (4-aminophenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 1,3-bis (3-aminophenoxy) benzene, 1,3- Bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, bis (4- (4-aminophenoxy) phenyl) sulfone, Examples thereof include bis (4- (3-aminophenoxy) phenyl) sulfone. Commercially available products may be used as the amine resin, for example, "KAYABOND C-200S", "KAYABOND C-100", "Kayahard A-A", "Kayahard AB", "Kayahard" manufactured by Nippon Kayaku Co., Ltd. Examples include "AS" and "Epicure W" manufactured by Mitsubishi Chemical Corporation.

Examples of the acid anhydride-based resin as the component (b) include a resin having one or more acid anhydride groups in one molecule. Specific examples of the acid anhydride-based resin include phthalic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrohydride phthalic acid, methylnadic acid anhydride, and hydride methylnadic acid anhydride. Trialkyltetrahydrohydride phthalic acid, dodecenyl anhydride succinic acid, 5- (2,5-dioxotetrahydro-3-franyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, trimellith anhydrous Acid, pyromellitic anhydride, benzophenone tetracarboxylic acid dianhydride, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 3,3'-4,4'-diphenyl Sulphontetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-franyl) -naphtho [1,2-C] furan-1, Examples thereof include 3-dione, ethylene glycol bis (anhydrotrimethylate), and polymer-type acid anhydrides such as styrene / maleic acid resin in which styrene and maleic acid are copolymerized.

(B) The curing agent as a component is any of a phenol-based resin, a naphthol-based resin, a benzoxazine-based resin, an active ester-based resin, a cyanate ester-based resin, a carbodiimide-based resin, an amine-based resin, and an acid anhydride-based resin. It is preferable that any one of an active ester resin, a phenol resin, a carbodiimide resin, and a naphthol resin is preferable, and one or more selected from a phenol resin, an active ester resin, and a cyanate ester resin. Is more preferable.

(B) When the epoxy resin and the curing agent are contained as the components, the amount ratio of the epoxy resin to all the curing agents is [total number of epoxy groups of the epoxy resin]: [total number of reactive groups of the curing agent]. The ratio is preferably in the range of 1: 0.01 to 1: 5, more preferably 1: 0.1 to 1: 3, and even more preferably 1: 0.3 to 1: 2. Here, the "number of epoxy groups in the epoxy resin" is a value obtained by summing up all the values obtained by dividing the mass of the non-volatile component of the epoxy resin present in the resin composition by the epoxy equivalent. The "number of active groups of the curing agent" is a total value obtained by dividing the mass of the non-volatile component of the curing agent present in the resin composition by the active group equivalent. By setting the amount ratio of the epoxy resin and the curing agent within such a range as the component (b), a cured product having excellent flexibility can be obtained.

(B) The content of the curing agent as a component is preferably 1% by mass or more, more preferably 3% by mass, based on 100% by mass of the non-volatile component in the resin composition from the viewpoint of obtaining a cured product having excellent flexibility. % Or more, more preferably 5% by mass or more, preferably 40% by mass or less, more preferably 30% by mass or less, still more preferably 20% by mass or less.

The content of the component (b) is preferably 10% by mass or more, more preferably 13% by mass or more, and further, with respect to 100% by mass of the non-volatile component in the resin composition, from the viewpoint of remarkably obtaining the effect of the present invention. It is preferably 15% by mass or more, preferably 50% by mass or less, more preferably 45% by mass or less, and further preferably 40% by mass or less.

<(C) Curing accelerator>
The resin composition may contain (c) a curing accelerator as an arbitrary component. Examples of the curing accelerator include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, metal-based curing accelerators, and the like, as well as amine-based curing accelerators and imidazole-based curing agents. A curing accelerator is preferable, and an amine-based curing accelerator is more preferable. The curing accelerator may be used alone or in combination of two or more.

Examples of the phosphorus-based curing accelerator include triphenylphosphine, phosphonium borate compound, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, and (4-methylphenyl) triphenylphosphonium 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) phenol, and 1,8-diazabicyclo. (5,4,0) -Undecene and the like are mentioned, and 4-dimethylaminopyridine and 1,8-diazabicyclo (5,4,0) -Undecene are preferable.

Examples of the imidazole-based curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, and the like. 2-Ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-Cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl- 2-Phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecyl Imidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4- Diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2- Phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline Examples thereof include imidazole compounds such as 2-phenylimidazolin and adducts of the imidazole compound and an epoxy resin, and 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole are preferable.

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

Examples of the guanidine-based curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1- (o-tolyl) guanidine, dimethylguanidine, diphenylguanidine, and trimethylguanidine. Tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo [4.4.0] deca-5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] Deca-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylviguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1 -Allylbiguanide, 1-phenylbiguanide, 1- (o-tolyl) biguanide and the like can be mentioned, with dicyandiamide and 1,5,7-triazabicyclo [4.4.0] deca-5-ene being preferred.

Examples of the metal-based curing accelerator include organic metal complexes or organic metal salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organic metal complex include an organic cobalt complex such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, an organic copper complex such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. Examples thereof include organic zinc complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, zinc stearate and the like.

(C) The content of the curing accelerator is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and particularly preferably 0.% by mass, when the non-volatile component in the resin composition is 100% by mass. It is 03% by mass or more, preferably 3% by mass or less, more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less.

When the curing agent as the component (b) is not contained, the content of the curing accelerator (c) is preferably 0.01% by mass or more when the non-volatile component in the resin composition is 100% by mass. It is more preferably 0.02% by mass or more, particularly preferably 0.03% by mass or more, preferably 3% by mass or less, more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less.

<(D) Thermoplastic resin>
The resin composition may contain (d) a thermoplastic resin as an arbitrary component. (D) Examples of the thermoplastic resin include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, and polyetheretherketone resin. , Polyester resin and the like, and phenoxy resin is preferable. The thermoplastic resin may be used alone or in combination of two or more.

(D) The polystyrene-equivalent weight average molecular weight of the thermoplastic resin is preferably 10,000 or more, more preferably 15,000 or more, and further preferably 20,000 or more. The upper limit is preferably 100,000 or less, more preferably 70,000 or less, still more preferably 60,000 or less. (D) The polystyrene-equivalent weight average molecular weight of the thermoplastic resin is measured by a gel permeation chromatography (GPC) method. Specifically, (d) the polystyrene-equivalent weight average molecular weight of the thermoplastic resin was determined by using LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device and Shodex K-800P / K-804L manufactured by Showa Denko Co., Ltd. as a column. / K-804L can be calculated by measuring the column temperature at 40 ° C. using chloroform or the like as a mobile phase and using a standard polystyrene calibration curve.

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, anthracene skeleton, adamantan skeleton, and terpene. Examples thereof include phenoxy resins having one or more skeletons selected from the group consisting of skeletons and trimethylcyclohexane skeletons. 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 alone or in combination of two or more. 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" (bisphenol acetophenone) manufactured by Mitsubishi Chemical Corporation. (Skeletal-containing phenoxy resin), and also "FX280" and "FX293" manufactured by Nittetsu Chemical & Materials Co., Ltd., "YL7500BH30", "YX6954BH30", "YX7553", "YX7553BH30" manufactured by Mitsubishi Chemical Co., Ltd., Examples thereof include "YL7553BH30", "YL7769BH30", "YL6794", "YL7213", "YL7282" and "YL7482".

Examples of the polyvinyl acetal resin include polyvinyl formal resin and polyvinyl butyral resin, and polyvinyl butyral resin is preferable. Specific examples of the polyvinyl acetal resin include, for example, "Electrified Butyral 4000-2", "Electrified Butyral 5000-A", "Electrified Butyral 6000-C", "Electrified Butyral 6000-EP", Sekisui Chemical Co., Ltd. Examples thereof include Eslek BH series, BX series (for example, BX-5Z), KS series (for example, KS-1), BL series, and BM series manufactured by Chemical Industry Co., Ltd.

Specific examples of the polyimide resin include "Ricacoat SN20" and "Ricacoat PN20" manufactured by NEW JAPAN CHEMICAL CO., LTD. Specific examples of the polyimide resin include a linear polyimide obtained by reacting a bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (polyimide described in JP-A-2006-37083), and a polysiloxane skeleton. Examples thereof include modified polyimides such as contained polyimides (polyimides described in JP-A-2002-12667 and JP-A-2000-31386).

Specific examples of the polyamide-imide resin include "Vilomax HR11NN" and "Vilomax HR16NN" manufactured by Toyobo Co., Ltd. Specific examples of the polyamide-imide resin include modified polyamide-imides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamide-imide) manufactured by Hitachi Chemical Industries, Ltd.

Specific examples of the polyether sulfone resin include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd. Specific examples of the polyphenylene ether resin include oligophenylene ether / styrene resin “OPE-2St 1200” manufactured by Mitsubishi Gas Chemical Company, Inc. Specific examples of the polyetheretherketone resin include "Sumiproi K" manufactured by Sumitomo Chemical Co., Ltd. Specific examples of the polyetherimide resin include "Ultem" manufactured by GE.

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

Examples of the polyolefin resin include ethylene-based copolymers such as low-density polyethylene, ultra-low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer. Resin: Polyethylene, polyethylene-propylene block copolymers and the like, polyolefin-based elastomers and the like can be mentioned.

Examples of the polyester resin include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene terephthalate resin, polybutylene naphthalate resin, polytrimethylene terephthalate resin, polytrimethylene naphthalate resin, polycyclohexanedimethylterephthalate resin and the like.

Among them, as the (d) thermoplastic resin, a phenoxy resin and a polyvinyl acetal resin are preferable. Thus, in one preferred embodiment, the thermoplastic resin comprises one or more selected from the group consisting of phenoxy resins and polyvinyl acetal resins. Among them, as the thermoplastic resin, a phenoxy resin is preferable, and a phenoxy resin having a weight average molecular weight of 10,000 or more is particularly preferable.

(D) The content of the thermoplastic resin is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, still more preferably 0.%, When the non-volatile component in the resin composition is 100% by mass. It is 5% by mass or more. The upper limit is preferably 5% by mass or less, more preferably 4% by mass or less, and further preferably 3% by mass or less.

<(E) Elastomer>
In the resin composition, (e) an elastomer may be used as an arbitrary component in addition to the above-mentioned components. The component (e) may be used alone or in combination of two or more.

The component (e) is selected from a polybutadiene structure, a polysiloxane structure, a poly (meth) acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, a polyester structure, and a polycarbonate structure in the molecule. It is preferable that the resin has one or more structures, and the resin is selected from a polybutadiene structure, a poly (meth) acrylate structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyester structure, or a polycarbonate structure in the molecule. A resin having a seed or two or more kinds of structures is more preferable, and a resin having any one of a polybutadiene structure, a polyester structure, and a polycarbonate structure in the molecule is more preferable. The term "(meth) acrylate" is a term that includes methacrylate, acrylate, and a combination thereof. These structures may be contained in the main chain or the side chain of the elastomer molecule.

The component (e) is preferably in a high molecular weight from the viewpoint of remarkably obtaining the effect of the present invention. The number average molecular weight (Mn) of the component (e) is preferably 1,000 or more, more preferably 1500 or more, and further preferably 3000 or more and 5000 or more. The upper limit is preferably 1,000,000 or less, more preferably 900,000 or less. The number average molecular weight (Mn) is a polystyrene-equivalent number average molecular weight measured using GPC (gel permeation chromatography).

The component (e) preferably has a low glass transition temperature (Tg) from the viewpoint of remarkably obtaining the effect of the present invention. The glass transition temperature (Tg) of the component (e) is preferably 30 ° C. or lower, more preferably 20 ° C. or lower, still more preferably 10 ° C. or lower. It is preferably −60 ° C. or higher, more preferably −50 ° C. or higher, and even more preferably −45 ° C. or higher.

The component (e) has a functional group capable of reacting with the epoxy resin as the component (b) from the viewpoint of reacting with the epoxy resin as the component (b) to cure the resin composition and increasing the peel strength. Is preferable. The functional groups that can react with the epoxy resin include functional groups that appear by heating.

In one preferred embodiment, the functional group capable of reacting with the epoxy resin as the component (b) consists of a group consisting of a hydroxy group, a carboxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group and a urethane group. One or more functional groups to be selected. Among them, as the functional group, a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group and a urethane group are preferable, and a hydroxy group, an acid anhydride group, a phenolic hydroxyl group and an epoxy group are more preferable, and phenol. Phenol is particularly preferred. However, when an epoxy group is contained as the functional group, the weight average molecular weight (Mw) of the component (e) is preferably 5,000 or more.

A preferred embodiment of the component (e) is a resin containing a polybutadiene structure, and the polybutadiene structure may be contained in the main chain or the side chain. The polybutadiene structure may be partially or completely hydrogenated. A resin containing a polybutadiene structure is called a polybutadiene resin.

Specific examples of the polybutadiene resin include "Ricon 130MA8", "Ricon 130MA13", "Ricon 130MA20", "Ricon 131MA5", "Ricon 131MA10", "Ricon 131MA17", "Ricon 131MA20", and "Ricon" manufactured by Clay Valley. 184MA6 "(polybutadiene containing acid anhydride group)," GQ-1000 "(hydroxyl-terminated, carboxyl group-introduced polybutadiene)," G-1000 "," G-2000 "," G-3000 "(both ends) Hydroxyl-terminated polybutadiene), "GI-1000", "GI-2000", "GI-3000" (hydroxyl-terminated polybutadiene with both ends), "FCA-061L" (hydrogenated polybutadiene skeleton epoxy resin) manufactured by Nagase ChemteX, etc. Can be mentioned. As one embodiment, a linear polyimide using hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride as raw materials (polyimide described in JP-A-2006-37083, International Publication No. 2008/153208), a phenolic hydroxyl group. Examples include contained butadiene. The content of the butadiene structure of the polyimide resin is preferably 60% by mass to 95% by mass, more preferably 75% by mass to 85% by mass. For the details of the polyimide resin, the description of JP-A-2006-37083 and International Publication No. 2008/153208 can be referred to, and the contents thereof are incorporated in the present specification.

A preferred embodiment of the component (e) is a resin containing a poly (meth) acrylate structure. A resin containing a poly (meth) acrylate structure is called a poly (meth) acrylic resin. As poly (meth) acrylic resin, Teisan resin manufactured by Nagase ChemteX, "ME-2000", "W-116.3", "W-197C", "KG-25", "KG-25" manufactured by Negami Kogyo Co., Ltd. KG-3000 ”and the like.

A preferred embodiment of the component (e) is a resin containing a polycarbonate structure. A resin containing a polycarbonate structure is called a polycarbonate resin. Examples of the polycarbonate resin include "T6002" and "T6001" (polycarbonate diol) manufactured by Asahi Kasei Chemicals, "C-1090", "C-2090" and "C-3090" (polycarbonate diol) manufactured by Kuraray. Be done. Further, a linear polyimide made from a hydroxyl group-terminated polycarbonate, a diisocyanate compound and a tetrabasic acid anhydride can also be used. The content of the carbonate structure of the polyimide resin is preferably 60% by mass to 95% by mass, more preferably 75% by mass to 85% by mass. The details of the polyimide resin can be referred to in International Publication No. 2016/129541, which is incorporated herein by reference.

Another embodiment of the component (e) is a resin containing a polysiloxane structure. A resin containing a polysiloxane structure is called a siloxane resin. Examples of the siloxane resin include "SMP-2006", "SMP-2003PGMEA", "SMP-5005PGMEA" manufactured by Shinetsu Silicone Co., Ltd., amine group-terminated polysiloxane, and linear polyimides made from tetrabasic acid anhydride (international). Publication No. 2010/053185, JP-A-2002-12667, JP-A-2000-31386, etc.) and the like can be mentioned.

Another embodiment of the component (e) is a resin containing a polyalkylene structure and a polyalkylene oxy structure. A resin containing a polyalkylene structure is referred to as a polyalkylene resin, and a resin containing a polyalkylene oxy structure is referred to as a polyalkylene oxy resin. As the polyalkylene oxy structure, a polyalkylene oxy structure having 2 to 15 carbon atoms is preferable, a polyalkylene oxy structure having 3 to 10 carbon atoms is more preferable, and a polyalkylene oxy structure having 5 to 6 carbon atoms is further preferable. Specific examples of the polyalkylene resin and the polyalkylene oxy resin include "PTXG-1000" and "PTXG-1800" manufactured by Asahi Kasei Fibers Corporation.

Another embodiment of the component (e) is a resin containing a polyisoprene structure. A resin containing a polyisoprene structure is called a polyisoprene resin. Specific examples of the polyisoprene resin include "KL-610" and "KL613" manufactured by Kuraray.

Another embodiment of the component (e) is a resin containing a polyisobutylene structure. A resin containing a polyisobutylene structure is called a polyisobutylene resin. Specific examples of the polyisobutylene resin include "SIBSTAR-073T" (styrene-isobutylene-styrene triblock copolymer) and "SIBSTAR-042D" (styrene-isobutylene block copolymer) manufactured by Kaneka. ..

A preferred embodiment of the component (e) is a resin containing a polyester structure. A resin containing a polyester structure is called a polyester resin. As polyester resins, Toyobo's "Byron 600", "Byron 560", "Byron 230", "Byron GK-360", "Byron BX-1001", Mitsubishi Chemical's "LP-035", " "LP-011", "TP-220", "TP-249", "SP-185" and the like can be mentioned.

(E) The content of the elastomer is preferably 5% by mass or more, more preferably 10% by mass or more, when the non-volatile component in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the effect of the present invention. More preferably, it is 15% by mass or more. The upper limit is preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 40% by mass or less.

<(F) Other additives>
In addition to the above-mentioned components, the resin composition may further contain other additives as arbitrary components. Examples of such additives include flame retardants; organic fillers; organic metal compounds such as organic copper compounds, organic zinc compounds and organic cobalt compounds; thickeners; defoaming agents; leveling agents; adhesion imparting agents; Examples thereof include resin additives such as colorants. One of these additives may be used alone, or two or more of these additives may be used in combination at any ratio.

Examples of the flame retardant include phosphazene compounds, organic phosphorus-based flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone-based flame retardants, metal hydroxides and the like, and phosphazene compounds are preferable. The flame retardant may be used alone or in combination of two or more.

The phosphazene compound is not particularly limited as long as it is a cyclic compound containing nitrogen and phosphorus as constituent elements, but the phosphazene compound is preferably a phosphazene compound having a phenolic hydroxyl group.

Specific examples of the phosphazene compound include, for example, "SPH-100", "SPS-100", "SPB-100" and "SPE-100" manufactured by Otsuka Chemical Co., Ltd., and "FP-100" manufactured by Fushimi Pharmaceutical Co., Ltd. Examples thereof include "FP-110", "FP-300", "FP-400", and "SPH-100" manufactured by Otsuka Chemical Co., Ltd. is preferable.

As the flame retardant other than the phosphazene compound, a commercially available product may be used, and examples thereof include "HCA-HQ" manufactured by Sanko Co., Ltd. and "PX-200" manufactured by Daihachi Chemical Industry Co., Ltd. As the flame retardant, one that is hard to hydrolyze is preferable, and for example, 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide and the like are preferable.

The content of the flame retardant is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, still more preferably 0.3% by mass or more when the non-volatile component in the resin composition is 100% by mass. Is. The upper limit is preferably 15% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less.

As the organic filler, any organic filler that can be used for forming the insulating layer of the printed wiring board may be used, and examples thereof include rubber particles, polyamide fine particles, and silicone particles. As the rubber particles, commercially available products may be used, and examples thereof include "EXL2655" manufactured by Dow Chemical Japan Co., Ltd., "AC3401N" and "AC3816N" manufactured by Aica Kogyo Co., Ltd. The organic filler may be used alone or in combination of two or more.

The content of the organic filler is preferably 0.1% by mass or more, more preferably 0.15% by mass or more, still more preferably 0.2% by mass, when the non-volatile component in the resin composition is 100% by mass. That is all. The upper limit is preferably 10% by mass or less, more preferably 5% by mass or less, and further preferably 3% by mass or less.

The method for preparing the resin composition is not particularly limited, and examples thereof include a method of mixing and dispersing the compounding components together with a solvent and the like using a rotary mixer or the like.

[Resin sheet with support]
The resin sheet with a support includes a support and a resin composition layer provided on the support and formed of the resin composition. The resin composition is as described in the [Resin composition] column.

The thickness of the resin composition layer is preferably 150 μm or less, more preferably, from the viewpoint of reducing the thickness of the printed wiring board and providing a cured product having excellent insulating properties even if the cured product of the resin composition is a thin film. Is 100 μm or less, more preferably 50 μm or less. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be usually 1 μm or more, 5 μm or more, or the like.

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

When a film made of a plastic material is used as a support, the plastic material may be, for example, polyethylene terephthalate (hereinafter abbreviated as "PET") or polyethylene naphthalate (hereinafter abbreviated as "PEN"). ) And other polyesters, polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylics such as polymethylmethacrylate (PMMA), cyclic polyolefins, triacetylcellulose (TAC), polyethersulfide (PES), polyethers. Examples thereof include ketones and polyimides. Of these, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is particularly preferable.

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

The support may be matted, corona-treated, or antistatic-treated on the surface to be joined to the resin composition layer.

Further, as the support, a support with a release layer having a release layer on the surface to be joined to the resin composition layer may be used. Examples of the release agent used for the release layer of the support with the release layer include one or more release agents selected from the group consisting of alkyd resin, polyolefin resin, urethane resin, and silicone resin. .. As the support with a release layer, a commercially available product may be used, for example, "SK-1", "AL-5", "AL-7" manufactured by Lintec Corporation, "Lumirror T60" manufactured by Toray Industries, Inc., Teijin Corporation. PET film having a mold release layer containing an alkyd resin-based mold release agent as a main component, such as "Purex" manufactured by Unitika Ltd. and "Unipeel" manufactured by Unitika Ltd .; "U2-NR1" manufactured by DuPont Film Co., Ltd., etc. Will be.

The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, and more preferably in the range of 10 μm to 60 μm. When a support with a release layer is used, the thickness of the entire support with a release layer is preferably in the above range.

In one embodiment, the resin sheet with a support may further include other layers, if necessary. Examples of such other layers include a protective film similar to the support provided on the surface of the resin composition layer that is not bonded to the support (that is, the surface opposite to the support). Be done. The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to suppress the adhesion and scratches of dust and the like on the surface of the resin composition layer.

For the resin sheet with a support, for example, a resin varnish in which a resin composition is dissolved in an organic solvent is prepared, the resin varnish is applied onto the support using a die coater or the like, and the resin composition layer is further dried. Can be manufactured by forming.

Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone (MEK) and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate; cellosolve and butyl carbitol and the like. Carbitols; aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone. The organic solvent may be used alone or in combination of two or more.

Drying may be carried out by a known method such as heating or blowing hot air. The drying conditions are not particularly limited, but the resin composition layer is dried so that the content of the organic solvent is 10% by mass or less, preferably 5% by mass or less. Although it depends on the boiling point of the organic solvent in the resin varnish, for example, when a resin varnish containing 30% by mass to 60% by mass of an organic solvent is used, the resin composition is obtained by drying at 50 ° C. to 150 ° C. for 3 to 10 minutes. A layer can be formed.

The resin sheet with a support can be rolled up and stored. When the resin sheet with a support has a protective film, it can be used by peeling off the protective film.

[Manufacturing method of printed wiring board]
The method for manufacturing a printed wiring board of the present invention is as follows.
(A) A step of forming an opening in the insulating layer containing the cured product of the resin composition by a laser, and (B) a step of sandblasting the opening with abrasive grains to form a via hole, in this order. Including in.

As described above, a method using a laser can be considered as a method for forming a via hole in the insulating layer. When a via hole is formed using only a laser, a haloing phenomenon may occur due to the heat generated by irradiating the laser. In addition to the method of forming a via hole using a laser, there is a method of forming a via hole by sandblasting. If the via hole is formed only by the sandblasting treatment, the occurrence of the haloing phenomenon can be suppressed, but it is difficult to form the via hole having a small diameter, and the processing speed of the via hole may be slow.

In the present invention, an opening is first formed in the insulating layer by a laser, and then a via hole is formed by colliding abrasive grains with the bottom surface of the opening by sandblasting, whereby a via hole having a small diameter can be formed, and smear removal property is possible. It is possible to suppress the occurrence of the haloing phenomenon. Further, since the opening is formed as a part of the via hole by the laser and the entire via hole is not formed, the number of shots of the laser can be reduced. Further, since the via hole is formed in the opening formed by the laser by sandblasting, the deterioration of the resin around the bottom of the via hole can be suppressed, so that the occurrence of the haloing phenomenon can be suppressed and the processing time can be shortened. It is also possible (via workability).

Before performing the step (A), the method of manufacturing the printed wiring board is as follows.
It may include (1) a step of preparing an inner layer circuit board and (3) a step of forming an insulating layer on the main surface of the inner layer circuit board. Further, in order to use it for forming the insulating layer in the step (3), the method for manufacturing the printed wiring board is as follows.
(2) A step of preparing a resin sheet with a support, which comprises a support and a resin composition layer formed of the resin composition provided on the support.
May further be included. Hereinafter, each step of the method for manufacturing a printed wiring board will be described.

<Process (1)>
The step (1) is a step of preparing an inner layer circuit board. The inner layer circuit board usually includes a support board and a metal layer provided on the surface of the support board. The metal layer is exposed on the main surface of the inner layer circuit board, and via holes are formed in the area where the metal layer is located. Therefore, the area where the via hole is formed on the main surface of the inner layer circuit board is formed of the metal layer.

Examples of the material of the support substrate include a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, and the like. Examples of the material of the metal layer include a copper foil, a copper foil with a carrier, a material of a conductor layer described later, and the like, and a copper foil is preferable.

The arithmetic mean roughness (Ra) of the main surface of the inner layer circuit board is preferably 500 nm or less, more preferably 450 nm or less, still more preferably 400 nm or less, and 350 nm or less. By setting the arithmetic average roughness (Ra) of the main surface of the inner layer circuit board to 500 nm or less, it is possible to prevent the insulating layer formed on the main surface from penetrating deep into the inner layer circuit board, improving the workability of via holes. Can be made to. The lower limit is not particularly limited, but is preferably 10 nm or more, more preferably 50 nm or more, and further preferably 100 nm or more. The arithmetic mean roughness (Ra) of the main surface is a value measured according to ISO 25178 and can be measured using a non-contact type surface roughness meter. The main surface of the inner layer circuit board represents the surface of the inner layer circuit board provided with the insulating layer.

Further, when the arithmetic mean roughness (Ra) is not constant on the main surface, the arithmetic average roughness (Ra) of the main surface in the area where the metal layer is formed may be within the above range, and via holes are formed. It is preferable that the arithmetic mean roughness (Ra) of the main surface in the area is in the above range.

The ten-point average roughness (Rz) of the main surface of the inner layer circuit board is preferably 5000 nm or less, more preferably 4500 nm or less, and further preferably 4000 nm or less. By setting the ten-point average roughness (Rz) of the main surface of the inner layer circuit board to 5000 nm or less, it is possible to prevent the insulating layer formed on the main surface from penetrating deep into the inner layer circuit board, improving insulation reliability. Can be made to. The lower limit is not particularly limited, but is preferably 50 nm or more, more preferably 100 nm or more, and further preferably 1000 nm or more. The ten-point average roughness (Rz) of the main surface is a value measured according to ISO 25178, and can be measured using a non-contact type surface roughness meter.

Further, when the ten-point average roughness (Rz) is not constant on the main surface, it is preferable that the ten-point average roughness (Rz) of the main surface in the area where the metal layer is formed is in the above range. It is more preferable that the ten-point average roughness (Rz) of the main surface in the area where the via hole is formed is in the above range.

The arithmetic average roughness (Ra) and the ten-point average roughness (Rz) of the main surface of the inner layer circuit board can be adjusted within the above ranges by, for example, etching treatment and polishing.

<Process (2)>
Step (2) is a step of preparing a resin sheet with a support, which includes a support and a resin composition layer formed of the resin composition provided on the support. The resin sheet with a support is as described above.

<Process (3)>
The step (3) is a step of forming an insulating layer on the main surface of the inner layer circuit board. In the step (3), for example, a resin composition layer of a resin sheet with a support is laminated on the main surface of an inner circuit board, and the resin composition layer is thermally cured to form an insulating layer.

As an example shown in FIG. 1, the inner layer circuit board 10 includes a support substrate 11 and a metal layer 12 provided on the surface of the support substrate 11. In the step (3), a resin sheet with a support (not shown) is laminated on the main surface 10a of the inner layer circuit board 10 and the resin composition layer is thermally cured to form the insulating layer 22. Normally, since the insulating layer 22 is provided on the surface of the metal layer 12, the surface of the metal layer 12 opposite to the surface of the support substrate 11 is the main surface 10a. Although the metal layer 12 is provided on one surface of the support substrate 11 in FIG. 1, it may be provided on both surfaces of the support substrate 11.

The stacking of the inner layer circuit board and the resin sheet with the support can be performed, for example, by heat-pressing the resin sheet with the support from the support side to the inner layer circuit board. As a member for heat-crimping a resin sheet with a support to an inner layer circuit board (hereinafter, also referred to as “heat-crimping member”), for example, a heated metal plate (SUS end plate or the like) or a metal roll (SUS roll) or the like is used. Can be mentioned. Instead of pressing the heat-bonded member directly onto the resin sheet with support, press it through an elastic material such as heat-resistant rubber so that the resin sheet with support sufficiently follows the surface irregularities of the inner layer circuit board. Is preferable.

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

Lamination can be performed by a commercially available vacuum laminator. Examples of the commercially available vacuum laminator include a vacuum pressurizing laminator manufactured by Meiki Co., Ltd., a vacuum applicator manufactured by Nikko Materials, and a batch type vacuum pressurizing laminator.

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

After laminating the resin sheet with a support on the inner layer circuit board, the resin composition layer is thermally cured to form an insulating layer. The thermosetting conditions of the resin composition layer are not particularly limited, and the conditions usually adopted when forming the insulating layer of the printed wiring board may be used.

For example, the thermosetting conditions of the resin composition layer differ depending on the type of the resin composition and the like, but the curing temperature is preferably 120 ° C to 240 ° C, more preferably 150 ° C to 220 ° C, still more preferably 170 ° C to 210. ℃. The curing time can be preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, and even more preferably 15 minutes to 100 minutes.

Before the resin composition layer is thermally cured, the resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermosetting the resin composition layer, the resin composition layer is heated at a temperature of 50 ° C. or higher and lower than 120 ° C. (preferably 60 ° C. or higher and 115 ° C. or lower, more preferably 70 ° C. or higher and 110 ° C. or lower). Preheating may be performed for 5 minutes or longer (preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes, still more preferably 15 minutes to 100 minutes).

The thickness of the insulating layer is 25 μm or less, preferably 20 μm or less, more preferably 15 μm or less, still more preferably 10 μm or less, from the viewpoint of forming a via hole having a small diameter. The lower limit of the thickness of the insulating layer is not particularly limited, but may be usually 1 μm or more, 5 μm or more, or the like.

In step (3), instead of the method using a resin sheet, the resin composition may be applied directly on the main surface of the inner layer circuit board to form an insulating layer. The conditions for forming the insulating layer at that time are the same as the conditions for forming the insulating layer using the resin sheet with a support.

The elastic modulus of the insulating layer obtained by curing the resin composition layer at 200 ° C. for 90 minutes at 23 ° C. is preferably 0.1 GPa or more, more preferably 1 GPa or more, and more preferably 3 GPa or more from the viewpoint of improving via workability. It is preferably 30 GPa or less, more preferably 25 GPa or less, and further preferably 20 GPa or less. The elastic modulus can be measured by the method described in Examples described later.

The support may be removed after laminating the resin sheet with the support and before the thermosetting, or may be removed after the end of the step (A), or the resin sheet with the support may be removed after the laminating and the thermosetting. Alternatively, it may be removed after being used as a mask in the sandblasting treatment of the step (B).

<Process (A)>
The step (A) is a step of forming an opening in the insulating layer containing the cured product of the resin composition by a laser. As an embodiment of the step (A), as shown by an example in FIG. 2, the insulating layer 22 formed on the main surface 10a of the inner layer circuit board 10 is irradiated with a laser to form an opening 30.

It is preferable to irradiate the laser with a mask for sandblasting installed on the insulating layer 22. Therefore, the step (A) may include a step of forming a mask on the insulating layer 22 before the irradiation of the laser. Examples of the mask include a dry film, a metal foil, and a combination thereof. These masks can be provided on the insulating layer 22, for example, by laminating either a dry film or a metal leaf onto the insulating layer after the support has been peeled off.

As the dry film, a pattern dry film that can be obtained by exposure and development is preferable, and a film that is resistant to sandblasting in the step (B) described later is more preferable. Further, as the dry film, a photosensitive dry film made of a photoresist composition can be used. As such a dry film, for example, a dry film formed of a resin such as a novolak resin or an acrylic resin can be used.

Examples of the metal foil include copper foil, aluminum foil and the like, and copper foil is preferable. As the copper foil, a foil made of a single metal of copper may be used, and a foil made of an alloy of copper and another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used. You may use it.

The thickness of the mask of the dry film is preferably 10 μm or more, more preferably 15 μm or more, still more preferably 20 μm or more, preferably 100 μm or less, more preferably 70 μm or less, and further, from the viewpoint of improving the processability of the via hole. It is preferably 50 μm or less.

The thickness of the mask such as a metal foil is preferably 1 μm or more, more preferably 2 μm or more, still more preferably 3 μm or more, preferably 40 μm or less, more preferably 20 μm or less, from the viewpoint of improving the workability of the via hole. More preferably, it is 15 μm or less.

Further, the support 21 may be used as the mask. When the support 21 is used as a mask, the step of providing a mask different from the support 21 can be omitted, so that the manufacturing method can be simplified. In this embodiment, as shown in FIG. 2, an example in which the support 21 is used as a mask will be described.

The depth a of the opening is preferably 50% or more, more preferably 60% or more, still more preferably 70% or more, from the viewpoint of obtaining the effect of the present invention remarkably. The upper limit is preferably 95% or less, more preferably 90% or less, still more preferably 85% or less of the thickness of the insulating layer. The depth of the opening means the distance from the surface of the insulating layer in contact with the mask (support 21 in FIG. 2) to the bottom of the opening. The depth of the opening can be obtained by observing the difference between the unprocessed portion and the deepest portion of the insulating layer in cross section.

The opening diameter b of the opening can be the opening diameter (via diameter) of the via hole. The opening diameter b is preferably 100 μm or less, more preferably 75 μm or less, still more preferably 55 μm or less, preferably 5 μm or more, more preferably 10 μm or more, still more preferably 15 μm, from the viewpoint of forming a via hole having a small diameter. That is all. The opening diameter b represents the diameter at the upper end of the insulating layer 22 as shown in FIG.

The ratio of the depth a of the opening to the opening diameter b of the opening (depth a of the opening / opening diameter b of the opening) is preferably 0.1 from the viewpoint of significantly obtaining the effect of the present invention. The above is more preferably 0.3 or more, still more preferably 0.5 or more, preferably 3 or less, more preferably 1 or less, still more preferably 0.7 or less.

Examples of the laser light source that can be used for forming the opening include a CO ₂ laser (carbon dioxide gas laser), a UV-YAG laser, a UV laser, a YAG laser, an excima laser, and the like. Of these, a CO ₂ laser or a UV-YAG laser is preferable from the viewpoint of processing speed and cost.

When irradiating a CO ₂ laser, the number of shots is preferably 2 or less, more preferably 1 from the viewpoint of improving via workability. In order to keep the number of shots within the above range, it is preferable to set the energy and pulse width of the CO ₂ laser to a certain value or more. The energy of the CO ₂ laser is preferably 0.3 W or more, more preferably 0.5 W or more, still more preferably 1.0 W or more, preferably 30 W or less, more preferably 20 W or less, still more preferably 15 W or less. .. The pulse width of the CO ₂ laser is preferably 3 μsec or more, more preferably 5 μsec or more, still more preferably 8 μsec or more, preferably 40 μsec or less, more preferably 30 μsec or less, still more preferably 20 μsec or less.

When irradiating with a UV-YAG laser, the number of shots is preferably 20 or less, more preferably 15 from the viewpoint of improving via workability. In order to keep the number of shots within the above range, it is preferable to set the energy and pulse width of the UV-YAG laser to a certain value or more. The energy of the UV-YAG laser is preferably 0.05 W or more, more preferably 0.10 W or more, still more preferably 0.15 W or more, preferably 20 W or less, more preferably 10 W or less, still more preferably 5 W or less. be.

The formation of via holes can be carried out using a commercially available laser device. Examples of commercially available carbon dioxide laser devices include "LC-2E21B / 1C" manufactured by Hitachi Via Mechanics, "ML605GTWII" manufactured by Mitsubishi Electric, and a substrate drilling laser machine manufactured by Matsushita Welding System. Moreover, as a UV-YAG laser apparatus, for example, "LU-2L212 / M50L" manufactured by Via Mechanics, etc. can be mentioned.

In the step (A), as described above, it is preferable to irradiate the insulating layer 22 on which the mask such as the support 21 is installed with a laser to form the opening 30. Therefore, preferably, the opening 30 is formed so as to communicate with the mask as well as the insulating layer 22. Therefore, when the support 21 is used as a mask as in the example shown in FIG. 2, the opening 30 can be continuously formed in the insulating layer 22 and the support 21. In this case, the ratio of the total value c of the thickness of the mask (thickness of the support 21 in FIG. 2) and the depth a of the opening to the opening diameter of the via hole formed by the step (B) (total value c / open). The diameter) is preferably 3 or less, more preferably 2.5 or less, still more preferably 2 or less, preferably 0.1 or more, and more preferably 0.3 or more, from the viewpoint of remarkably obtaining the effect of the present invention. , More preferably 0.5 or more. Here, the thickness of the mask means the thickness of the mask before the step (B) is performed.

Further, the ratio (total value c / opening diameter b) of the total value c of the thickness of the mask and the depth a of the opening to the opening diameter b of the opening 30 before the step (B) is the effect of the present invention. Is preferably 3 or less, more preferably 2.5 or less, still more preferably 2 or less, preferably 0.1 or more, more preferably 0.3 or more, still more preferably 0.5 or more. Is.

The total value c of the thickness of the mask and the depth of the opening is preferably 50% or more, more preferably 60% or more of the total thickness of the mask and the insulating layer from the viewpoint of remarkably obtaining the effect of the present invention. % Or more, more preferably 70% or more. The upper limit is preferably 95% or less, more preferably 90% or less, still more preferably 80% or less of the total thickness of the mask and the insulating layer.

<Process (B)>
The step (B) is a step of performing sandblasting treatment using abrasive grains on the opening to form a via hole. As a detailed embodiment of the step (B), a via hole is formed by colliding the abrasive grains with the bottom surface of the opening through the mask. The mask is preferably at least one of a support, a dry film and a metal leaf opened by the step (A), and a support is more preferable.

As shown in FIG. 3, in the step (B), sandblasting is performed and the abrasive grains are made to collide with the bottom surface of the opening 30 to form the via hole 40. Here, the sandblasting treatment is to inject abrasive grains or a slurry solution of abrasive grains from a nozzle onto the surface of a portion not covered with a mask such as a support, a dry film, or a metal foil by air jetted at a predetermined pressure. This is a process of forming via holes by causing the abrasive grains to collide with the insulating layer. The sandblasting treatment in the step (B) may be either a drive last treatment for spraying abrasive grains or a wet blasting treatment for spraying a slurry solution of abrasive grains, but from the viewpoint of forming a via hole having a small diameter, the wet blasting treatment is used. It is preferable to have.

The modified Mohs hardness of the abrasive grains used in the sandblasting treatment is preferably 1 or more, more preferably 5 or more, still more preferably 6 or more, or 7 or more from the viewpoint of forming a via hole having a small diameter by the sandblasting treatment. The upper limit can usually be 15 or less. The modified Mohs hardness of the abrasive grains can be measured using, for example, a Mohs hardness meter.

The abrasive grains include inorganic compounds such as silica and glass; metal compounds such as steel, stainless steel, zinc and copper; ceramics such as garnet, zirconia, silicon carbide, alumina and boron carbide; particles mainly composed of dry ice and the like. And so on. Among them, inorganic compounds and ceramics are preferable, and any one of alumina, silicon carbide, and silica is preferable, from the viewpoint of remarkably obtaining the desired effect of the present invention. As the silica, crystalline silica is preferable.

Commercially available products can be used as the abrasive grains. Examples of commercially available products include "DAW-03" manufactured by Denka Co., Ltd., "AY2-75" manufactured by Nittetsu Chemical & Materials Co., Ltd. (alumina); "GP # 4000" manufactured by Shinano Electric Smelting Co., Ltd., and "SER-A06" (carbide). Silicon); "IMSIL A-8" (crystalline silica) manufactured by Ryumori Co., Ltd .; "Fuji Random WA" (molten alumina) manufactured by Fuji Seisakusho.

The average particle size of the abrasive grains is 0.5 μm or more, preferably 1 μm or more, and more preferably 2 μm or more. By setting the lower limit of the average particle size of the abrasive grains within such a range, the via workability can be improved. In addition, it is possible to suppress the blowback of the abrasive grains in the sandblasting process, and it is possible to suppress the grinding of the mask. Blow-back of abrasive grains is a phenomenon in which the abrasive grains sprayed on the opening reduce the collision speed due to the action of the airflow that enters the opening and returns, and is particularly remarkable for abrasive grains with a small average particle size. be. The upper limit of the average particle size of the abrasive grains is 20 μm or less, preferably 15 μm or less, and more preferably 10 μm or less. By setting the upper limit of the average particle size of the abrasive grains within such a range, the workability of a small diameter via hole can be improved. The average particle size of the abrasive grains can be measured, for example, by observation with a scanning electron microscope, and the details can be measured by the method described in JP-A-2008-41932.

The pressure (machining pressure) for injecting the abrasive grains is preferably 0.05 MPa or more, more preferably 0.1 MPa or more, still more preferably 0.15 MPa or more, preferably 1 MPa or less, and more preferably 0.8 MPa or less. , More preferably 0.5 MPa or less. By keeping the processing pressure within such a range, the processing time can be shortened. The processing pressure here is a value on the surface of the insulating layer.

The distance between the nozzle and the mask is preferably 200 mm or less, more preferably 190 mm or less, further preferably 180 mm or less, preferably 10 mm or more, more preferably 15 mm or more, still more preferably 20 mm or more. By keeping the above distance within such a range, via holes can be efficiently formed.

By using the manufacturing method of the present invention, even if the top diameter of the via hole is usually a small diameter, the processing time of the sandblasting process can be shortened. The processing time is preferably less than 10 minutes, more preferably 8 minutes or less, still more preferably 5 minutes or less and less than 5 minutes. The lower limit is not particularly limited, but may be 0.1 minutes or more.

Although FIG. 3 shows an example in which the support 21 is used as a mask, either a metal foil or a dry film may be used as a mask instead of the support 21.

<Other processes>
In manufacturing the printed wiring board, after the step (B) is completed, (C) a step of roughening the insulating layer and (D) a step of forming the conductor layer may be further carried out. These steps (C) and (D) may be carried out according to various methods known to those skilled in the art used for manufacturing a printed wiring board. Further, if necessary, the formation of the insulating layer and the conductor layer in the steps (A) to (D) may be repeated to form a multilayer wiring board. Further, the method for manufacturing a printed wiring board may include a step of removing the mask at an appropriate timing. Usually, the mask is removed after step (B) and before step (C).

The step (C) is a step of roughening the insulating layer (also referred to as desmear treatment). Normally, in this step (C), the abrasive grains are also removed. The procedure and conditions for the roughening treatment are not particularly limited, and known procedures and conditions usually used for forming the insulating layer of the printed wiring board can be adopted. For example, the insulating layer can be roughened by performing a swelling treatment with a swelling liquid, a roughening treatment with an oxidizing agent, and a neutralization treatment with a neutralizing liquid in this order. The swelling solution used for the roughening treatment is not particularly limited, and examples thereof include an alkaline solution and a surfactant solution, preferably an alkaline solution, and the alkaline solution is more preferably a sodium hydroxide solution or a potassium hydroxide solution. preferable. Examples of commercially available swelling liquids include "Swelling Dip Security SBU" and "Swelling Dip Security P" manufactured by Atotech Japan. Be done. The swelling treatment with the swelling liquid is not particularly limited, but can be performed, for example, by immersing the insulating layer in the swelling liquid at 30 ° C. to 90 ° C. for 1 minute to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling liquid at 40 ° C to 80 ° C for 5 to 15 minutes. The oxidizing agent used for the roughening treatment is not particularly limited, and examples thereof include an alkaline permanganate solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. The roughening treatment with an oxidizing agent such as an alkaline permanganate solution is preferably performed by immersing the insulating layer in an oxidizing agent solution heated to 60 ° C to 100 ° C for 10 to 30 minutes. The concentration of permanganate in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as "Concentrate Compact CP" and "Dozing Solution Security P" manufactured by Atotech Japan. The neutralizing solution used for the roughening treatment is preferably an acidic aqueous solution, and examples of commercially available products include "Reduction Solution Security P" manufactured by Atotech Japan. The treatment with the neutralizing solution can be performed by immersing the treated surface that has been roughened with the oxidizing agent in the neutralizing solution at 30 ° C. to 80 ° C. for 1 minute to 30 minutes. From the viewpoint of workability and the like, a method of immersing the object roughened with an oxidizing agent in a neutralizing solution at 40 ° C to 70 ° C for 5 to 20 minutes is preferable.

In one embodiment, the arithmetic mean roughness (Ra) of the surface of the insulating layer after the roughening treatment is preferably 500 nm or less, more preferably 400 nm or less, still more preferably 300 nm or less. The lower limit is not particularly limited, but is preferably 30 nm or more, more preferably 40 nm or more, and further preferably 50 nm or more. The arithmetic mean roughness (Ra) of the insulating layer surface can be measured using a non-contact surface roughness meter.

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

The conductor layer may have a single-layer structure, a single metal layer made of different types of metals or alloys, or a multi-layer structure in which two or more alloy layers are laminated. When the conductor layer has a multi-layer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc or titanium, or an alloy layer of nickel-chromium alloy.

The thickness of the conductor layer depends on the design of the desired printed wiring board, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

In one embodiment, the conductor layer may be formed by plating. For example, a conductor layer having a desired wiring pattern can be formed by plating the surface of an insulating layer by a conventionally known technique such as a semi-additive method or a full additive method, and the semi-additive can be manufactured from the viewpoint of ease of manufacture. It is preferably formed by the method. Hereinafter, an example of forming the conductor layer by the semi-additive method will be shown.

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

Since the method for manufacturing a printed wiring board of the present invention performs the step (A) and the step (B), it exhibits a characteristic that a via hole having a small diameter can be formed. The top diameter (via diameter) of the via hole is preferably 100 μm or less, more preferably 75 μm or less, still more preferably 55 μm or less, preferably 5 μm or more, more preferably 10 μm or more, still more preferably 15 μm or more. Details of the via diameter measurement method and evaluation can be performed by the method described in Examples described later.

Since the method for manufacturing a printed wiring board of the present invention performs the step (A) and the step (B), it exhibits a characteristic of being excellent in smear removal property. Therefore, when the via hole is formed by the method of the present invention and then the desmear treatment is performed in which the swelling solution, the roughening solution, and the neutralizing solution are immersed in this order, no resin residue is found at the bottom of the via hole. The smear removal property can be evaluated by the method described in Examples described later.

The method for manufacturing a printed wiring board of the present invention exhibits a characteristic that the haloing phenomenon is suppressed. Specifically, even if the via hole diameter is within the above range and small, the haloing phenomenon can be suppressed. Hereinafter, the haloing phenomenon will be described with reference to the drawings.

FIG. 4 shows a surface 22U of a conventional printed wiring board in which a via hole is formed by a laser, which is an insulating layer 22 immediately before the conductor layer is formed and is opposite to a metal layer 12 (not shown in FIG. 4). Is a plan view schematically showing. FIG. 5 is a cross-sectional view schematically showing an insulating layer 22 immediately before a conductor layer is formed in a conventional printed wiring board in which a via hole is formed by a laser, together with a metal layer 12 of an inner circuit board. FIG. 5 shows a cross section of the insulating layer 22 cut through a plane passing through the center 220C of the via bottom 220 of the via hole 40 and parallel to the thickness direction of the insulating layer 22.

As shown in FIG. 5, when the via hole 40 is formed by the laser, the discolored portion 240 may occur due to the deterioration of the resin due to the heat of the laser. The discolored portion 240 may be eroded by a chemical during the roughening treatment, the insulating layer 22 may be peeled off from the metal layer 12, and a continuous gap portion 260 may be formed from the edge 250 of the via bottom 220 (haloing phenomenon). ..

In the present invention, since the sandblasting treatment that does not easily generate heat after forming the opening by the laser is adopted, the deterioration of the resin can be suppressed. Therefore, the peeling of the insulating layer 22 from the metal layer 12 can be suppressed, and the size of the gap 260 can be reduced.

The edge 250 of the via bottom (beer bottom (via bottom)) 220 corresponds to the inner peripheral edge of the gap 260. Therefore, the distance Wb from the edge 250 of the via bottom 220 to the end portion on the outer peripheral side of the gap portion 260 (that is, the end portion on the side far from the center 220C of the via bottom 220) 270 is the size of the gap portion 260 in the in-plane direction. Equivalent to. Here, the in-plane direction means a direction perpendicular to the thickness direction of the insulating layer 22. Further, in the following description, the distance Wb may be referred to as a haloing distance Wb from the edge 250 of the via bottom 220 of the via hole 40. The degree of suppression of the haloing phenomenon can be evaluated by the haloing distance Wb from the edge 250 of the via bottom 220. Specifically, it can be evaluated that the smaller the haloing distance Wb from the edge 250 of the via bottom 220, the more effectively the haloing phenomenon can be suppressed.

According to the production method of the present invention, even if a via hole having a top diameter of 50 μm or less is formed, the haloing distance Wb from the edge 250 of the via bottom 220 of the via hole 40 of the insulating layer 22 is preferably 5 μm or less, more preferably 5 μm or less. It can be 4 μm or less, more preferably 3 μm or less. The lower limit is not particularly limited, but may be 0 μm or more, 0.1 μm or more, and the like.

The manufacturing method of the present invention can manufacture a printed wiring board having a via hole and a trench, as shown by an example in FIGS. 6 to 10. For details, as shown in FIG. 6, an insulating layer 22 is formed on the inner layer circuit board 10 before the step (A) is performed, and the metal foil 60 is further laminated on the insulating layer 22. After laminating the metal foil 60, a pattern etching process is performed on the metal foil 60 as shown in FIG. 7 to remove a part of the metal foil 60 to form a hole 61. After that, as shown by an example in FIG. 8, a step (A) of irradiating a predetermined portion of the metal foil 60 with a laser is performed to form an opening 30. Next, as shown in FIG. 9, by performing step (B), a via hole 40 is formed from the opening 30, and a trench 50 is formed by colliding abrasive grains with the bottom of the hole 61 by sandblasting. Will be done. Then, as shown by an example in FIG. 10, the via hole 40 and the trench 50 are embedded by electrolytic plating to form a filled via 80. After forming the field via 80, the metal leaf 60 may be removed, if necessary.
Further, a metal foil is laminated on the resin composition layer of the resin sheet with the support to obtain a metal foil with the resin composition layer, the metal foil with the resin composition layer is laminated on the inner layer circuit board, and the insulating layer and the metal foil are formed on the inner layer. It may be formed on a circuit board.

Further, according to the manufacturing method of the present invention, as shown by an example in FIGS. 11 to 16, a printed wiring board having a pattern conductor layer can be manufactured. For details, as shown in FIG. 11, an insulating layer 22 is formed on the inner layer circuit board 10 before the step (A) is performed, and the metal foil 60 and the dry film 70 are further laminated on the insulating layer 22. After laminating the metal foil 60 and the dry film 70, as shown in FIG. 12, a part of the dry film 70 is exposed and developed to form a hole 71 in which a part of the dry film 70 is removed. Then, as shown in FIG. 13, a step (A) of irradiating a predetermined portion of the dry film 70 with a laser is performed to form an opening 30. Next, the via hole 40 is formed from the opening 30 by performing the step (B) as shown in FIG. 14 as an example. After the step (B) is completed, the via holes 40 and the holes 71 are embedded by electrolytic plating to form a filled via 80 as shown in FIG. 15, and the dry film (not shown) is removed as shown in FIG. 16 as an example. And form a patterned conductor layer. A metal foil 60 may be used as the plating seed layer for the electrolytic plating.
Before removing the dry film, the surface of the filled via 80 may be polished by buffing or the like in order to adjust the height of the filled via 80, if necessary.
Further, a metal foil is laminated on the resin composition layer of the resin sheet with the support to obtain a metal foil with the resin composition layer, the metal foil with the resin composition layer is laminated on the inner layer circuit board, and the insulating layer and the metal foil are formed on the inner layer. It may be formed on a circuit board.

The manufacturing method of the present invention can manufacture a printed wiring board having a via hole and a trench, as shown by an example in FIGS. 17 to 21. For details, as shown in FIG. 17, an insulating layer 22 is formed on the inner layer circuit board 10 before the step (A) is performed, and a dry film 70 is further laminated on the insulating layer 22. After laminating the dry fill 70, a hole 71 is formed by removing a part of the dry film 70 by exposing and developing a part of the dry film 70 as shown in FIG. 18 as an example. Then, as shown in FIG. 19, a step (A) of irradiating a predetermined portion of the dry film 70 with a laser is performed to form an opening 30. Next, as shown in FIG. 20, by performing step (B), a via hole 40 is formed from the opening 30, and a trench 50 is formed by colliding abrasive grains with the bottom of the hole 71 by sandblasting. To. After that, as shown by an example in FIG. 21, the via hole 40 and the trench 50 are embedded by electrolytic plating to form a filled via 80. After the formation of the field via 80, the dry film 70 may be removed, if necessary.
Before removing the dry film, the surface of the filled via 80 may be polished by buffing or the like in order to adjust the height of the filled via 80, if necessary.

[Semiconductor device]
The semiconductor device of the present invention includes a printed wiring board. The semiconductor device of the present invention can be manufactured by using the printed wiring board obtained by the manufacturing method of the present invention.

Examples of semiconductor devices include various semiconductor devices used in electric products (for example, computers, mobile phones, digital cameras, televisions, etc.) and vehicles (for example, motorcycles, automobiles, trains, ships, aircraft, etc.).

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

The mounting method of the semiconductor chip in manufacturing a semiconductor device 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 a bumpless build-up layer. Examples thereof include a mounting method using (BBUL), a mounting method using an anisotropic conductive film (ACF), and a mounting method using a non-conductive film (NCF). Here, the "mounting method using the bumpless build-up layer (BBUL)" means "a mounting method in which the semiconductor chip is directly embedded in the recess of the printed wiring board and the semiconductor chip is connected to the wiring on the printed wiring board". Is.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples. In the following description, "parts" and "%" representing quantities mean "parts by mass" and "% by mass", respectively, unless otherwise specified. The operations described below were performed in an environment of normal temperature and pressure unless otherwise specified.

<Synthesis Example 1: Elastomer Synthesis>
A bifunctional hydroxy group-terminated polybutadiene (“G-3000” manufactured by Nippon Soda Co., Ltd., number average molecular weight = 3000, hydroxy group equivalent = 1800 g / eq.) 69 g and an aromatic hydrocarbon mixed solvent (Idemitsu Petroleum) are placed in a reaction vessel. 40 g of "Ipsol 150" manufactured by Kagaku Co., Ltd.) and 0.005 g of dibutyltin laurate were added, mixed and uniformly dissolved. When the temperature became uniform, the temperature was raised to 60 ° C., and 8 g of isophorone diisocyanate (“IPDI” manufactured by Evonik Degussa Japan Co., Ltd., isocyanate group equivalent = 113 g / eq.) Was added with further stirring, and the reaction was carried out for about 3 hours.

Next, 23 g of cresol novolak resin (“KA-1160” manufactured by DIC, hydroxyl group equivalent = 117 g / eq.) And 60 g of ethyldiglycol acetate (manufactured by Daicel) were added to the reaction product, and the temperature reached 150 ° C. with stirring. The temperature was raised and the reaction was carried out for about 10 hours. The disappearance of the NCO peak of 2250 cm ^-1 was confirmed by FT-IR. Confirmation of the disappearance of the NCO peak was regarded as the end point of the reaction, and the temperature of the reaction product was lowered to room temperature. Then, the reaction product was filtered through a 100-mesh filter cloth to obtain an elastomer having a butadiene structure and a phenolic hydroxyl group (phenolic hydroxyl group-containing butadiene resin: 50% by mass of non-volatile component). The number average molecular weight of the elastomer was 5900, and the glass transition temperature was −7 ° C.

<Manufacturing of resin sheet 1 with support>
Biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC-3000-L", epoxy equivalent about 269 g / eq.) 10 parts, liquid 1,4-glycidylcyclohexane (Nittetsu Chemical & Materials Co., Ltd. "ZX1658", epoxy equivalent) Approximately 135 g / eq.) 10 parts, bixylenol type epoxy resin (Mitsubishi Chemical's "YX4000H", epoxy equivalent about 185 g / eq.) 10 parts, active ester compound (DIC's "HPC-8000-65T", active 50 parts of a basic equivalent of about 223 g / eq., A toluene solution containing 65% by mass of a non-volatile component, a triazine skeleton-containing phenolic curing agent (“LA-3018-50P” manufactured by DIC, a hydroxyl group equivalent of about 151 g / eq., Solid content 50). 2 parts of 2-methoxypropanol solution), 10 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Co., Ltd., 1: 1 solution of MEK and cyclohexanone with a solid content of 30% by mass), carbodiimide compound ("V-" manufactured by Nisshinbo Chemical Co., Ltd.) 03 ”, 10 parts of a toluene solution having an active group equivalent of about 216 g / eq. And a solid content of 50% by mass), and spherical silica surface-treated with an aminosilane-based coupling agent (“KBM573” manufactured by Shinetsu Chemical Industry Co., Ltd.) (average particle size). 0.5 μm, 220 parts of Admatex “SO-C2”), phosphorus-based flame retardant (“HCA-HQ-HS” manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9- Oxa-10-phosphaphenanthrene-10-oxide) 1 part, rubber particles (Aika Kogyo Co., Ltd., Staphyroid AC3816N) 1 part, curing accelerator (4-dimethylaminopyridine (DMAP), solid content 5% by mass) 5 parts of MEK solution), 25 parts of methyl ethyl ketone, and 15 parts of cyclohexanone were mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish 1.

Next, the resin varnish 1 was uniformly spread on the mold release surface of the support, a polyethylene terephthalate film with mold release treatment (“AL5” manufactured by Lintec Corporation, thickness 38 μm) so that the thickness of the resin composition layer was 40 μm. It was applied and dried at 80 to 120 ° C. (average 100 ° C.) for 6 minutes to prepare a resin sheet 1 with a support. Further, by changing the coating thickness of the resin varnish 1, the resin sheet 1 with a support having the thickness of the resin composition layer after drying of 20 μm and 15 μm was also produced.

<Manufacturing of resin sheet 2 with support>
30 parts of biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC-3000-L", epoxy equivalent about 269 g / eq.), Biphenyl type A epoxy resin (Mitsubishi Chemical Co., Ltd. "828EL", epoxy equivalent about 180 g / eq.). ) 20 parts, tetraphenylethane type epoxy resin (Mitsubishi Chemical "jER1031S", epoxy equivalent about 198 g / eq.), Triazine skeleton-containing phenol novolac-based curing agent (DIC "LA-7054", hydroxyl group equivalent about) 125 g / eq., 60% solid content MEK solution) 10 parts, phenol novolac-based curing agent (DIC's "TD2090", hydroxyl equivalent about 105 g / eq.) 6 parts, phenoxy resin (Mitsubishi Chemical's "YX7553BH30" , 8 parts of MEK with a solid content of 30% by mass and a 1: 1 solution of cyclohexanone), spherical silica surface-treated with an aminosilane-based coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Industry Co., Ltd.) (average particle size 0.5 μm, ad 140 parts of "SO-C2" manufactured by Matex Co., Ltd., phosphorus-based flame retardant ("HCA-HQ-HS" manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phos Mix 5 parts of faphenanthrene-10-oxide), 3 parts of curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with 5% by mass of solid content), 25 parts of methyl ethyl ketone, and 15 parts of cyclohexanone, and rotate at high speed. The resin varnish 2 was produced by uniformly dispersing it with a mixer.

In the production of the resin sheet 1 with a support, the resin varnish 1 was changed to the resin varnish 2. Except for the above items, the resin sheet 2 with a support was produced in the same manner as in the production of the resin sheet 1 with a support.

<Manufacturing of resin sheet 3 with support>
20 parts of bisphenol A type epoxy resin (Mitsubishi Chemical Corporation "828EL", epoxy equivalent about 180 g / eq.), Naftor type epoxy resin (Nittetsu Chemical & Materials Co., Ltd. "ESN-475V", epoxy equivalent about 332 g / eq.). ) 10 parts, bisphenol type epoxy resin (Mitsubishi Chemical Corporation "YX4000H", epoxy equivalent about 185 g / eq.), 10 parts, naphthylene ether type epoxy resin (DIC company "HP6000", epoxy equivalent about 260 g / eq.). ) 20 parts, cyanate ester-based curing agent (“BA230S75” manufactured by Ronza Japan, cyanate equivalent of about 235 g / eq., MEK solution of 75% by mass of non-volatile component), cyanate ester-based curing agent (“BADBy” manufactured by Ronza Japan). , Cyanate equivalent about 142 g / eq.), Active ester compound (DIC "HPC-8000-65T", active group equivalent about 223 g / eq., Toluene solution with 65% by mass of non-volatile component), phenoxy Spherical silica surface-treated with 8 parts of resin (Mitsubishi Chemical Corporation "YX7553BH30", solid content 30% by mass MEK and cyclohexanone 1: 1 solution), aminosilane coupling agent (Shinetsu Chemical Industry Co., Ltd. "KBM573") (Average particle size 0.5 μm, “SO-C2” manufactured by Admatex) 170 parts, curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution having a solid content of 5% by mass), 3 parts, cobalt (III) A resin varnish 3 was prepared by mixing 5 parts of a 1% by mass MEK solution of acetylacetonate (manufactured by Tokyo Kasei Co., Ltd.), 40 parts of methyl ethyl ketone, and 20 parts of cyclohexanone and uniformly dispersing them with a high-speed rotary mixer.

In the production of the resin sheet 1 with a support, the resin varnish 1 was changed to the resin varnish 3. Except for the above items, the resin sheet 3 with a support was produced in the same manner as in the production of the resin sheet 1 with a support.

<Manufacturing of resin sheet 4 with support>
Phenolic phthalimidine type epoxy resin ("WHR-991S" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent approx. 265 g / eq.) 5 parts, biphenyl type epoxy resin ("NC-3000-L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent) Approximately 269 g / eq.) 20 parts, 50 parts of the elastomer obtained in Synthesis Example 1, spherical silica surface-treated with a methacrylic silane coupling agent (“KBM503” manufactured by Shin-Etsu Chemical Industry Co., Ltd.) (average particle size 0.08 μm, Specific surface area 30.7m ² / g, Denka "UFP-30") 15 parts, phosphorus-based flame retardant (Sanko "HCA-HQ-HS", 10- (2,5-dihydroxyphenyl) -10- Hydro-9-oxa-10-phosphaphenanslen-10-oxide) 5 parts, hardening accelerator (1-benzyl-2-phenylimidazole (“1B2PZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.)) with a solid content of 10% by mass 2 parts of the methyl ethyl ketone solution) and 20 parts of the methyl ethyl ketone were mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish 4.

In the production of the resin sheet 1 with a support, the resin varnish 1 was changed to the resin varnish 4. Except for the above items, the resin sheet 4 with a support was produced in the same manner as in the production of the resin sheet 1 with a support.

<Manufacturing of resin sheet 5 with support>
In the production of the resin sheet 1 with a support
1) Aminosilane-based coupling of 220 parts of spherical silica (average particle size 0.5 μm, Admatex's “SO-C2”) surface-treated with an aminosilane-based coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.). Change to 270 parts of spherical alumina (average particle size 5.3 μm, Denka “DAW-0525”) surface-treated with an agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.).
2) Further, 50 parts of spherical alumina (average particle size 0.3 μm, “ASFP-20” manufactured by Denka Co., Ltd.) surface-treated with an aminosilane-based coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) was used.
Except for the above items, the resin sheet 5 with a support was produced in the same manner as the resin sheet 1 with a support.

The components used in the preparation of the resin varnishes 1 to 5 and their blending amounts (mass parts of non-volatile components) are shown in the table below. The content of the component (a) represents the content when the non-volatile component in the resin composition is 100% by mass.

<Evaluation of elastic modulus>
(1) Preparation of cured product for evaluation Glass cloth base material epoxy resin double-sided copper-clad laminate on the release agent-treated PET film (Lintec Corporation "501010", thickness 38 μm, 240 mm square) Plates (“R5715ES” manufactured by Panasonic Corporation, thickness 0.7 mm, 255 mm square) were stacked and the four sides were fixed with polyimide adhesive tape (width 10 mm) (hereinafter, may be referred to as “fixed PET film”).

The prepared resin sheets 1 to 5 with a support having a resin thickness of 40 μm are laminated on the release-treated surface of the above-mentioned “fixed PET film” using a batch type vacuum pressure laminator (MVLP-500 manufactured by Meiki Co., Ltd.). bottom. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.

Next, the support was peeled off, and the resin sheet with the support was heat-cured under the curing conditions of 90 minutes after being placed in an oven at 190 ° C.

After thermosetting, the polyimide adhesive tape is peeled off, the cured product is removed from the glass cloth base material epoxy resin double-sided copper-clad laminate, and the PET film (Lintec Corporation "501010") is also peeled off to obtain a sheet-shaped cured product. rice field. The obtained cured product is referred to as an "evaluation cured product".

(2) Evaluation of elastic modulus The obtained cured product for evaluation was subjected to a tensile test of the cured product using a Tensilon universal tester (manufactured by A & D Co., Ltd.) in accordance with Japanese Industrial Standards (JIS K7127). The elastic modulus at ° C was measured.

<Example 1>
(1) Laminating of Resin Sheet with Support The prepared resin sheet 1 with a support having a resin thickness of 40 μm is subjected to a microetching agent (Mech Co., Ltd.) using a batch type vacuum pressure laminator (MVLP-500 manufactured by Meiki Co., Ltd.). The resin composition layer was laminated so as to be in contact with both sides of the laminated plate whose copper surface was roughened by the above-mentioned “CZ8201”). Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.

(2) Curing of Resin Composition Layer The laminated resin sheet with a support was cured at 180 ° C. for 30 minutes to form an insulating layer.

(3) Formation of via hole (3-1) Formation of opening by laser An opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 50 μm, and the depth of the opening was 30 μm. The depth of the opening was obtained by calculating the difference between the unprocessed portion and the deepest portion of the insulating layer by observing the cross section.

(3-2) Sandblasting Next, using # 2000 alumina abrasive grain slurry (average particle size 6.7 μm) as the abrasive grains, sandblasting the openings using the support opened by the CO ₂ laser as a mask. This was performed to form a via hole (top diameter (diameter) is 50 μm). After sandblasting, the support was peeled off to obtain an evaluation substrate 1.

<Example 2>
In Example 1, the resin sheet 1 with a support was changed to the resin sheet 2 with a support. An evaluation substrate 2 was obtained in the same manner as in Example 1 except for the above items.

<Example 3>
In Example 1, the resin sheet 1 with a support was changed to the resin sheet 3 with a support. An evaluation substrate 3 was obtained in the same manner as in Example 1 except for the above items.

<Example 4>
In Example 1, the resin sheet 1 with a support was changed to the resin sheet 4 with a support. An evaluation substrate 4 was obtained in the same manner as in Example 1 except for the above items.

<Example 5>
In Example 1, the resin sheet 1 with a support was changed to the resin sheet 5 with a support. An evaluation substrate 5 was obtained in the same manner as in Example 1 except for the above items.

<Example 6>
(1) Preparation of Copper Foil with Resin Composition Layer Resin varnish on copper foil with carrier (Mitsui Metal Mining Co., Ltd., Microsin MTEx, copper foil thickness 3 μm) so that the thickness of the resin composition layer is 40 μm. 1 was uniformly applied and dried at 80 to 120 ° C. (average 100 ° C.) for 6 minutes to prepare a copper foil with a resin composition layer.

(2) Laminating of Copper Foil with Resin Composition Layer The obtained copper foil with resin composition layer was applied to both sides of a laminated plate whose copper surface was roughened with a micro-etching agent (“CZ8201” manufactured by MEC). A vacuum-pressurized laminator (MVLP-500, manufactured by Meiki Co., Ltd.) was used to laminate the resin composition layer so as to be in contact with the laminated plate. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.

(3) Curing of Resin Composition Layer The resin composition layer laminated with the copper foil with a carrier was cured under the curing conditions of 180 ° C. for 30 minutes to form an insulating layer.

(4) Formation of via hole (4-1) Formation of opening by laser After peeling off the carrier, an opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 50 μm, and the depth of the opening was 30 μm.

(4-2) Sandblasting Next, # 2000 alumina abrasive grain slurry (average particle size 6.7 μm) was used as the abrasive grains, and the opening was sandblasted using the copper foil opened by the CO ₂ laser as a mask. To form a via hole (top diameter (diameter) is 50 μm). After the sandblasting process, the copper foil was peeled off to obtain an evaluation substrate 6.

<Example 7>
(1) Laminating of Resin Sheet with Support The prepared resin sheet 1 with a support with a resin thickness of 40 μm is subjected to a copper foil with a carrier (Mitsui) using a batch type vacuum pressure laminator (MVLP-500 manufactured by Meiki Co., Ltd.). Laminated so that the resin composition layer was in contact with Microsin MTEx manufactured by Mitsui Mining & Smelting Co., Ltd. (thickness of copper foil 3 μm). The laminating was reduced in pressure for 30 seconds to a pressure of 13 hPa or less, and then pressed at 100 ° C. and a pressure of 0.74 MPa for 30 seconds to obtain a copper foil with a resin composition layer.

(2) Laminating of Copper Foil with Resin Composition Layer The obtained copper foil with resin composition layer was applied to both sides of a laminated plate whose copper surface was roughened with a micro-etching agent (“CZ8201” manufactured by MEC). A vacuum-pressurized laminator (MVLP-500, manufactured by Meiki Co., Ltd.) was used to laminate the resin composition layer so as to be in contact with the laminated plate. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.

(3) Curing of Resin Composition Layer The resin composition layer was cured under curing conditions of 180 ° C. for 30 minutes to form an insulating layer.

(4) Formation of Opening of Copper Foil By etching with the above-mentioned micro-etching agent, an opening for forming a trench was formed in a part of the copper foil with a carrier.

(5) Formation of via hole (5-1) Formation of opening by laser An opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 50 μm, and the depth of the opening was 30 μm.

(5-2) Sandblasting Next, # 2000 alumina abrasive grain slurry (average particle size 6.7 μm) was used as the abrasive grains, and the opening was sandblasted using the copper foil opened by the CO ₂ laser as a mask. To form a via hole (top diameter (diameter) is 50 μm). Further, by sandblasting, the insulating layer was dug even in the portion where the hole for forming the trench was formed, and the trench was formed. After the sandblasting process, the copper foil was peeled off to obtain an evaluation substrate 7.

<Example 8>
In Example 7, (3) the following operation was performed after the resin composition layer was cured, and (4) the opening of the copper foil was not formed. An evaluation substrate 8 was obtained in the same manner as in Example 7 except for the above items.

(4) Lamination of Dry Film A dry film (NCM325, 25 μm thick) manufactured by Nikko Materials Co., Ltd. was laminated on the surface of the copper foil. To laminate the dry film, use a batch type vacuum pressurizing laminator (“MVLP-500” manufactured by Meiki Co., Ltd.) to reduce the pressure for 30 seconds to reduce the atmospheric pressure to 13 hPa or less, and then set the pressure to 0.1 MPa and the temperature to 70 ° C. Then, pressurization was performed for 20 seconds. Then, a glass mask having a trench pattern was placed on a polyethylene terephthalate film which is a protective layer of a dry film, and UV irradiation was performed with an irradiation intensity of 20 mJ / cm ² by a UV lamp. After UV irradiation, a spray treatment was performed for 50 seconds at an injection pressure of 0.15 MPa using a 1% sodium carbonate aqueous solution at 25 ° C. Then, it was washed with water to form an opening for forming a trench pattern.

<Example 9>
(1) Preparation of Copper Foil with Resin Composition Layer Resin varnish 1 is uniformly applied onto the copper foil (JX Metal Co., Ltd., JDLC, thickness 12 μm) so that the thickness of the resin composition layer is 40 μm, and 80 A copper foil with a resin composition layer was prepared by drying at ~ 120 ° C. (average 100 ° C.) for 6 minutes.
(2) Laminating of Copper Foil with Resin Composition Layer with Copper Foil The obtained copper foil with resin composition layer was roughened on the copper surface with a microetching agent (“CZ8201” manufactured by MEC). A vacuum pressure laminator (MVLP-500, manufactured by Meiki Co., Ltd.) was used on both sides of the laminated plate so that the copper resin composition layer was laminated so as to be in contact with the laminated plate. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.

(3) Curing of Resin Composition Layer The resin composition layer is cured by curing the laminated plate on which the copper foil with the resin composition layer is laminated at 180 ° C. for 30 minutes to form an insulating layer, and the copper foil and the cured layer are formed. A laminated board with plastic was obtained.

(4) Half-etching of copper foil Half-etching was performed to reduce the thickness of copper from 12 μm to 5 μm by immersing the copper foil and the laminated board with a hardened layer in an iron chloride solution, and the adhered iron chloride solution was washed away with pure water. ..

(5) Pretreatment for laser processing Subsequently, a pretreatment for laser processing was performed using a pretreatment liquid for laser processing (“MULTIBOND 100” manufactured by MacDermid Performance Solutions Japan Co., Ltd.).

(6) Formation of via hole (6-1) Formation of opening by laser An opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 50 μm, and the depth of the opening was 30 μm.

(6-2) Sandblasting Next, # 2000 alumina abrasive grain slurry (average particle size 6.7 μm) was used as the abrasive grains, and the opening was sandblasted using the copper foil opened by the CO ₂ laser as a mask. To form a via hole (top diameter (diameter) is 50 μm). After the sandblasting process, the copper foil was peeled off to obtain an evaluation substrate 9.

<Example 10>
In Example 9, (4) half etching of the copper foil was not performed. An evaluation substrate 10 was obtained in the same manner as in Example 9 except for the above items.

<Example 11>
In Example 1, the resin sheet 1 with a support having a resin thickness of 40 μm is changed to the resin sheet 1 with a support having a resin thickness of 20 μm.
The via hole was formed as follows. An evaluation substrate 11 was obtained in the same manner as in Example 1 except for the above items.

(1) Formation of via hole (1-1) Formation of opening by laser An opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 30 μm, and the depth of the opening was 15 μm.

(1-2) Sandblasting Next, using # 3000 alumina abrasive grain slurry (average particle size 4.0 μm) as the abrasive grains, sandblasting the openings using the support opened by the CO ₂ laser as a mask. To form a via hole (top diameter (diameter) is 30 μm). After sandblasting, the support was peeled off to obtain an evaluation substrate 11.

<Example 12>
In Example 7, the resin sheet 1 with a support having a resin thickness of 40 μm is changed to the resin sheet 1 with a support having a resin thickness of 15 μm.
The via hole was formed as follows. An evaluation substrate 12 was obtained in the same manner as in Example 7 except for the above items.

(1) Formation of via hole (1-1) Formation of opening by laser An opening was formed using a UV-YAG laser processing machine (“LU-2L212 / M50L” manufactured by Via Mechanics, Inc.). The top diameter (diameter) of the opening on the surface of the insulating layer was 20 μm, and the depth of the opening was 12 μm.

(1-2) Sandblasting Next, using # 3000 alumina abrasive grain slurry (average particle size 4.0 μm) as the abrasive grains, sandblasting the openings using the copper foil opened by the UV-YAG laser as a mask. It was processed to form a via hole (top diameter (diameter) is 20 μm). After the sandblasting process, the copper foil was peeled off to obtain an evaluation substrate 12.

<Example 13>
In Example 12, the copper foil with a carrier (Mitsui Mining & Smelting Co., Ltd., Microsin MTEx, copper foil thickness 3 μm) was changed to a dry film (Asahi Kasei Co., Ltd., trade name “ATP-10VTDS”, thickness 10 μm). Except for the above, an evaluation substrate 13 was obtained in the same manner as in Example 12.

<Example 14>
In Example 13, an opening for a trench pattern was formed in the dry film using a mask before the opening was formed by the UV-YAG laser. Except for the above items, an evaluation substrate 14 was obtained in the same manner as in Example 13.

<Example 15>
In Example 2, the resin sheet 2 with a support having a resin thickness of 40 μm was changed to the resin sheet 2 with a support having a resin thickness of 25 μm.
The via hole was formed as follows. An evaluation substrate 15 was obtained in the same manner as in Example 2 except for the above items.

(1) Formation of via hole (1-1) Formation of opening by laser An opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 30 μm, and the depth of the opening was 25 μm.

(1-2) Via processing by sandblasting Next, using # 3000 alumina abrasive grain slurry (average particle size 4.0 μm) as abrasive grains, using the support opened by the CO ₂ laser as a mask, the opening A via hole (top diameter (diameter) of 30 μm) was formed by sandblasting. After sandblasting, the support was peeled off to obtain an evaluation substrate 15.

<Comparative Example 1>
In Example 1, the via holes were formed as follows. An evaluation substrate 16 was obtained in the same manner as in Example 1 except for the above items.

(1) Formation of via holes After forming the insulating layer, the PET film as a support was peeled off. A UV-YAG laser processing machine (“LU-2L212 / M50L” manufactured by Via Mechanics) was used to form a via hole in the insulating layer from which the support was peeled off, and an evaluation substrate 16 was obtained. The top diameter (diameter) of the via hole on the surface of the insulating layer was 50 μm.

<Comparative Example 2>
In Example 1, the via holes were formed as follows. An evaluation substrate 17 was obtained in the same manner as in Example 1 except for the above items.

(1) Formation of Via Hole A via hole was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics) to obtain an evaluation substrate 17. The top diameter (diameter) of the via hole on the surface of the insulating layer was 50 μm.

<Comparative Example 3>
In Example 1, the via holes were formed as follows. An evaluation substrate 18 was obtained in the same manner as in Example 1 except for the above items.

(1) Formation of via hole (1-1) Formation of opening by laser An opening was formed using a CO ₂ laser machine (“LC-2E21B / 1C” manufactured by Hitachi Via Mechanics). The top diameter (diameter) of the opening on the surface of the insulating layer was 50 μm, and the depth of the opening was 35 μm. This is called a board.

(1-2) Desmia-treated The substrate is immersed in a swolling solution, a swirling dip seculigand P containing diethylene glycol monobutyl ether manufactured by Atotech Japan, at 60 ° C. for 5 minutes, and then as a roughening solution, Atotech Japan Co., Ltd. Immerse in Concentrate Compact P (KMnO ₄ : 60 g / L, NaOH: 40 g / L aqueous solution) at 80 ° C. for 30 minutes, and finally use Atotech Japan's Reduction Shorusin Security as a neutralizing solution. By immersing in Gant P at 40 ° C. for 5 minutes, the bottom of the opening was scraped to form a via hole.

<Comparative Example 4>
In Example 1, the via holes were formed as follows. An evaluation substrate 19 was obtained in the same manner as in Example 1 except for the above items.

(1) Formation of via holes (1-1) Formation of via pattern by resist for sandblasting Vias with a diameter of 50 μm are formed on the surface of the insulating layer using a resist for sandblasting (NCM250, thickness 50 μm) manufactured by Nikko Materials. Patterning was performed.

(1-2) Sandblasting Next, using # 2000 alumina abrasive grain slurry (average particle size 6.7 μm) as the abrasive grains, sandblasting the via portion using the sandblasting resist on which the via pattern is formed as a mask. This was done to obtain an evaluation substrate 19.

<Comparative Example 5>
In Comparative Example 4, (1) the formation of the via hole was performed as follows. An evaluation substrate 20 was obtained in the same manner as in Comparative Example 4 except for the above items.

(1) Formation of via holes (1-1) Formation of via pattern by resist for sandblasting Vias with a diameter of 150 μm are formed on the surface of the insulating layer using a resist for sandblasting (NCM250, thickness 50 μm) manufactured by Nikko Materials. Patterning was performed.

(1-2) Via processing by sandblasting Next, using # 1200 alumina abrasive grain slurry (average particle size 9.5 μm) as abrasive grains, sandblasting the via portion using a sandblasting resist on which a via pattern is formed as a mask. Processing was performed to obtain an evaluation substrate 20.

<Evaluation of via diameter>
〇: A via hole can be formed with an opening diameter of 100 μm or less.
X: A via hole cannot be formed with an opening diameter of 100 μm or less.

<Evaluation of smear removal>
The evaluation substrates 1 to 20 obtained in Examples and Comparative Examples were immersed in a swelling solution, a swirling dip seculant P containing diethylene glycol monobutyl ether manufactured by Atotech Japan, at 60 ° C. for 5 minutes, and then crude. As a chemical solution, it is immersed in Concentrate Compact P (KMnO ₄ : 60 g / L, NaOH: 40 g / L aqueous solution) manufactured by Atotech Japan at 80 ° C. for 15 minutes, and finally as a neutralizing solution, manufactured by Atotech Japan. Soaked in the reduction sholysin securigant P at 40 ° C. for 5 minutes. After that, the via hole was observed with an electron microscope and evaluated according to the following criteria.
〇: No resin residue can be seen at the bottom of the via hole.
X: Resin residue can be seen at the bottom of the via hole.

<Evaluation of haloing>
The evaluation substrate after the evaluation of the smear removal property was cross-sectionally observed using a FIB-SEM composite device (“SMI3050SE” manufactured by SII Nanotechnology Inc.). Specifically, using a FIB (focused ion beam), the insulating layer was carved so that a cross section parallel to the thickness direction of the insulating layer and passing through the center of the via bottom of the via hole appeared. This cross section was observed by SEM. In some of the observed images, gaps formed by peeling the insulating layer from the copper foil of the inner layer substrate were seen continuously from the edge of the via bottom. Therefore, the distance from the edge of the via bottom to the end on the outer peripheral side of the gap was measured as the haloing distance and evaluated according to the following criteria.
〇: The haloing distance is 5 μm or less.
X: The haloing distance exceeds 5 μm.

<Evaluation of via workability>
(1) Evaluation of via workability by CO ₂ laser The evaluation was made by the number of shots required for the depth of the opening to be a predetermined depth by CO ₂ laser processing, and was evaluated according to the following criteria.
⊚: The number of shots is 1.
〇: The number of shots is 2.
×: The number of shots is 3 or more.

(2) Evaluation of via workability by UV-YAG laser The evaluation was made by the number of shots required to make the depth of the opening a predetermined depth by UV-YAG laser processing, and evaluated by the following criteria.
〇: The number of shots is 20 or less.
X: The number of shots exceeds 20.

(3) Evaluation of via workability by sandblasting The insulation layer at the bottom of the opening was removed, and the sandblasting time required for the conductor layer of the laminated board to be exposed was evaluated, and the evaluation was made according to the following criteria.
⊚: Processing time is less than 5 minutes.
〇: Processing time is 5 minutes or more and less than 10 minutes.
X: Processing time is 10 minutes or more.

＊表中、「ＷＢ」はウェットブラスト処理を意味する。無機充填材の含有量は、樹脂組成物中の不揮発成分を１００質量％としたときの値である。

* In the table, "WB" means wet blasting. The content of the inorganic filler is a value when the non-volatile component in the resin composition is 100% by mass.

10 Inner layer circuit board 11 Support board 12 Metal layer 10a Main surface 21 Support 22 Insulation layer 30 Opening 40 Via hole 50 Trench 60 Metal leaf 61 Hole 70 Dry film 71 Hole 80 Field via 22U Surface of insulation layer on the opposite side of the metal layer 220 Via bottom 220C Center of via bottom 240 Discoloration part 250 Edge of via bottom of via hole 260 Gap 270 End of outer circumference of gap a Depth of opening b Opening diameter (via hole diameter)
c Total value of mask thickness and opening depth Wb Haloing distance from the edge of the via bottom

Claims (12)

(A) A step of forming an opening in an insulating layer containing a cured product of a resin composition by a laser, and (B) a step of sandblasting the opening with abrasive grains to form a via hole, in this order. Including, how to manufacture a printed wiring board. The method for manufacturing a printed wiring board according to claim 1, wherein the average particle size of the abrasive grains is 10 μm or less. The method for manufacturing a printed wiring board according to claim 1 or 2, wherein the depth of the opening is 50% or more and 95% or less of the thickness of the insulating layer. The step (B) is a step of forming a via hole by colliding the abrasive grains with the bottom surface of the opening through the mask.
The printed wiring according to any one of claims 1 to 3, wherein the ratio (total value / opening diameter) of the total value of the thickness of the mask and the depth of the opening to the opening diameter of the via hole is 3 or less. How to make a board. The method for manufacturing a printed wiring board according to any one of claims 1 to 4, wherein the elastic modulus of the insulating layer at 23 ° C. is 0.1 GPa or more. The method for manufacturing a printed wiring board according to any one of claims 1 to 5, wherein the resin composition contains an inorganic filler. The method for manufacturing a printed wiring board according to claim 6, wherein the content of the inorganic filler is 20% by mass or more when the non-volatile component in the resin composition is 100% by mass. The method for manufacturing a printed wiring board according to any one of claims 1 to 7, wherein the resin composition contains a curable resin. The method for manufacturing a printed wiring board according to claim 8, wherein the content of the curable resin is 10% by mass or more when the non-volatile component in the resin composition is 100% by mass. The method for manufacturing a printed wiring board according to claim 8 or 9, wherein the curable resin contains an epoxy resin and a curing agent. The method for producing a printed wiring board according to claim 10, wherein the curing agent is at least one selected from a phenol-based resin, an active ester-based resin, and a cyanate ester-based resin. The method for manufacturing a printed wiring board according to any one of claims 1 to 11, wherein the laser is a CO ₂ laser or a UV-YAG laser.

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