JP7427455B2 - Adhesive films, printed wiring boards and semiconductor devices - Google Patents

Description

The present invention relates to a method for manufacturing a printed wiring board, a printed wiring board, and a semiconductor device.

In recent years, in printed wiring boards, build-up layers have become multilayered, and there is a demand for finer wiring and higher density wiring. The build-up layer is formed by a build-up method in which insulating layers and conductor layers are stacked alternately. In the build-up manufacturing method, the insulating layer is generally formed by thermosetting a resin composition. It is.
In printed wiring boards, it is also required to reduce electrical signal loss, and the insulating layer is required to have a low dielectric loss tangent. Therefore, for example, Patent Document 1 discloses a method for manufacturing a printed wiring board in which an insulating layer has a low dielectric loss tangent.

JP 2014-7403 Publication

A possible method for lowering the dielectric loss tangent of the insulating layer is to add a compound such as an active ester that exhibits a low dielectric loss tangent to the insulating layer. However, when a compound with a low dielectric loss tangent is added, hydrophobicity increases, resulting in high desmear resistance and too low roughness, resulting in poor dry film adhesion during wiring formation, which may have a negative impact on fine wiring formation. there were.
The problem to be solved by the present invention is to provide a method for manufacturing a printed wiring board that can improve the adhesion of a dry film even though the dielectric loss tangent is low.

As a result of intensive studies on the above-mentioned problems, the present inventors found that by forming irregularities on the surface of an insulating layer with a dielectric loss tangent of 0.005 or less using a support with a surface arithmetic mean roughness Ra ₁ of 200 nm or more. They found that the arithmetic mean roughness Ra ₂ of the surface of the insulating layer after roughening treatment becomes an appropriate value, and completed the present invention. The present invention is based on this new finding.

That is, the present invention includes the following contents.
[1] (A) A step of laminating a resin composition layer of an adhesive film comprising a support and a resin composition layer so as to be bonded to one surface or both surfaces of an inner layer substrate, and (B) a resin composition layer. (C) peeling off the support; (D) roughening the surface of the insulating layer; The arithmetic mean roughness Ra ₁ of the surface in contact with the resin composition layer is 200 nm or more, the dielectric loss tangent of the insulating layer formed in step (B) is 0.005 or less, and the surface after step (D) is 200 nm or more. A method for manufacturing a printed wiring board, wherein the arithmetic mean roughness Ra ₂ of the surface of the insulating layer is 200 nm to 800 nm.
[2] The method for manufacturing a printed wiring board according to [1], further comprising the step of (E) forming a wiring pattern of 20 μm or less.
[3] The difference between the arithmetic mean roughness Ra ₁ of the side of the support in contact with the resin composition layer and the arithmetic mean roughness Ra ₂ of the surface of the insulating layer after step (D) is 100 nm or less , [1] or [2].
[4] A printed wiring board comprising an insulating layer having a dielectric loss tangent of 0.005 or less and a surface arithmetic mean roughness Ra ₂ of 200 nm to 800 nm.
[5] A semiconductor device comprising a printed wiring board obtained by the method for manufacturing a printed wiring board according to any one of [1] to [3] or the printed wiring board according to [4].

According to the present invention, it is possible to provide a method for manufacturing a printed wiring board that can improve the adhesion of a dry film despite having a low dielectric loss tangent.

Before explaining in detail the method for manufacturing a printed wiring board of the present invention, the resin composition contained in the resin composition layer of the adhesive film comprising a support and a resin composition layer used for manufacturing the printed wiring board will be explained. explain.

(Resin composition)
The resin composition forming the resin composition layer in the adhesive film is not particularly limited, as long as its cured product has sufficient hardness and insulation properties. Examples of the resin composition include a composition containing a curable resin and a curing agent thereof. As the curable resin, conventionally known curable resins used for forming insulating layers of printed wiring boards can be used, and epoxy resins are particularly preferred. Thus, in one embodiment, the resin composition includes (a) an epoxy resin, (b) a curing agent, and (c) an inorganic filler. The resin composition may further contain additives such as a thermoplastic resin, a curing accelerator, a flame retardant, and rubber particles, if necessary.

Hereinafter, epoxy resins, curing agents, inorganic fillers, and additives that can be used as materials for the resin composition will be explained.

(a) Epoxy resin Examples of epoxy resins include bisphenol epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, and bisphenol AF epoxy resin, dicyclopentadiene epoxy resin, and trisphenol epoxy resin. Phenol 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, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin with butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring-containing epoxy resin, cyclohexanedimethanol type Examples include epoxy resin, naphthylene ether type epoxy resin, trimethylol type epoxy resin, tetraphenylethane type epoxy resin, and the like. Epoxy resins may be used alone or in combination of two or more.

Epoxy resins include bisphenol type epoxy resins, fluorine type epoxy resins (e.g. bisphenol AF type epoxy resins), dicyclopentadiene type epoxy resins, naphthalene type epoxy resins, biphenyl type epoxy resins, and mixtures of these epoxy resins. It is preferable to use one or more selected epoxy resins.

The epoxy resin preferably contains an epoxy resin having two or more epoxy groups in one molecule. When the nonvolatile component of the epoxy resin is 100% by mass, at least 50% by mass is preferably an epoxy resin having two or more epoxy groups in one molecule. Among them, epoxy resins that have two or more epoxy groups in one molecule and are liquid at a temperature of 20°C (hereinafter referred to as "liquid epoxy resins"), and three or more epoxy groups in one molecule, It is preferable to include an epoxy resin that is solid at a temperature of 20° C. (hereinafter referred to as "solid epoxy resin"). By using a liquid epoxy resin and a solid epoxy resin together as the epoxy resin, a resin composition having excellent flexibility can be obtained. Moreover, the breaking strength of the cured product of the resin composition is also improved.

From the viewpoint of lowering melt viscosity, liquid epoxy resins are preferred. Liquid epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, phenol novolak type epoxy resin, and alicyclic epoxy resin having an ester skeleton. , and epoxy resins having a butadiene structure are preferred, and bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol AF epoxy resins and naphthalene epoxy resins are more preferred. In particular, aromatic skeleton-containing epoxy resins are also preferred for lowering the average linear thermal expansion coefficient. Specific examples of liquid epoxy resins include "HP4032", "HP4032D", "HP4032SS" (naphthalene type epoxy resin) manufactured by DIC Corporation, "828US" and "jER828EL" (bisphenol A) manufactured by Mitsubishi Chemical Corporation. type epoxy resin), "jER807" (bisphenol F type epoxy resin), "jER152" (phenol novolac type epoxy resin), "YL7760" (bisphenol AF type epoxy resin), "ZX1059" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin), “EX-721” (glycidyl ester type epoxy resin) manufactured by Nagase ChemteX Co., Ltd., and “Celoxide 2021P” manufactured by Daicel Corporation (ester skeleton ``PB-3600'' (an epoxy resin with a butadiene structure). These may be used alone or in combination of two or more.

From the viewpoint of lowering the average linear thermal expansion coefficient, solid epoxy resins are preferred. Solid epoxy resins include naphthalene-type tetrafunctional epoxy resins, cresol novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol-type epoxy resins, biphenyl-type epoxy resins, naphthylene ether-type epoxy resins, Anthracene-type epoxy resins, bisphenol A-type epoxy resins, and tetraphenylethane-type epoxy resins are preferred, and naphthalene-type tetrafunctional epoxy resins, naphthol-type epoxy resins, and biphenyl-type epoxy resins are more preferred. In particular, polyfunctional epoxy resins are preferable because they have many crosslinking points and reduce the average linear thermal expansion coefficient. Specific examples of solid epoxy resins include "HP4032H" (naphthalene type epoxy resin), "HP-4700", "HP-4710" (naphthalene type tetrafunctional epoxy resin), and "N-690" manufactured by DIC Corporation. ” (cresol novolac type epoxy resin), “N-695” (cresol novolac type epoxy resin), “HP-7200” (dicyclopentadiene type epoxy resin), “HP-7200H”, “EXA7311”, “EXA7311-G3 ”, “EXA7311-G4”, “EXA7311-G4S”, “HP6000” (naphthylene ether type epoxy resin), “EPPN-502H” (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd., “NC7000L” (naphthol novolac type epoxy resin), "NC3000H", "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin), "ESN475V" (naphthol type epoxy resin) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., "ESN485" ” (naphthol novolac type epoxy resin), Mitsubishi Chemical Corporation's “YX4000H”, “YL6121” (biphenyl type epoxy resin), “YX4000HK” (bixylenol type epoxy resin), “YX8800” (anthracene type epoxy resin) , "PG-100" and "CG-500" manufactured by Osaka Gas Chemical Co., Ltd., "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Chemical Corporation, "jER1010" (solid state) manufactured by Mitsubishi Chemical Corporation bisphenol A type epoxy resin), "jER1031S" (tetraphenylethane type epoxy resin), and the like.

When the epoxy resin includes a solid epoxy resin and a liquid epoxy resin, the ratio of the mass M _S of the solid epoxy resin to the mass M _L of the liquid epoxy resin (M _S /M _L ) is in the range of 0.5 to 10. is preferred. By setting M _S /M _L within such a range, i) appropriate adhesion is provided when used in the form of a resin sheet, and ii) sufficient flexibility is provided when used in the form of a resin sheet. is obtained, the handleability is improved, and iii) a cured product having sufficient breaking strength can be obtained.

The content of the epoxy resin (a) in the resin composition is preferably 0.1% by mass or more, more preferably 5% by mass or more, and Preferably it is 10% by mass or more. The upper limit of the content of the epoxy resin is not particularly limited as long as the effects of the present invention can be achieved, but it is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 42% by mass or less.
Therefore, the content of the epoxy resin (a) in the resin composition is preferably 0.1 to 50% by mass, more preferably 10 to 45% by mass, and even more preferably 20 to 42% by mass. In the present invention, the content of each component in the resin composition is a value based on 100% by mass of nonvolatile components in the resin composition, unless otherwise specified.

The epoxy equivalent of the epoxy resin is preferably 50 to 5,000, more preferably 50 to 3,000, even more preferably 80 to 2,000, even more preferably 110 to 1,000. By falling within this range, the crosslinking density of the cured product will be sufficient and an insulating layer with small surface roughness can be provided. Note that the epoxy equivalent can be measured according to JIS K7236, and is the mass of the resin containing 1 equivalent of epoxy group.

The weight average molecular weight of the epoxy resin is preferably 100 to 5,000, more preferably 250 to 3,000, even more preferably 400 to 1,500. Here, the weight average molecular weight of the epoxy resin is the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC) method.

(b) Curing agent (b) Curing agent is not particularly limited as long as it has the function of curing the epoxy resin, but examples include phenolic curing agents, naphthol curing agents, active ester curing agents, and benzoxazine curing agents. , cyanate ester curing agents and carbodiimide curing agents, and active ester curing agents and cyanate ester curing agents are preferred from the viewpoint of setting the electrostatic tangent to 0.005 or less. One type of curing agent may be used alone, or two or more types may be used in combination.

As the phenol curing agent and the naphthol curing agent, from the viewpoint of heat resistance and water resistance, a phenol curing agent having a novolak structure or a naphthol curing agent having a novolak structure is preferable. Further, from the viewpoint of adhesion to the conductor layer (circuit wiring), a nitrogen-containing phenolic curing agent is preferred, and a triazine structure-containing phenol resin and a triazine structure-containing alkylphenol resin are more preferred. Among these, it is preferable to use a triazine structure-containing phenolic curing agent from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion (peel strength) with the conductor layer.

Specific examples of phenolic curing agents and naphthol curing agents include "MEH-7700", "MEH-7810", and "MEH-7851" manufactured by Meiwa Kasei Co., Ltd., and "MEH-7851" manufactured by Nippon Kayaku Co., Ltd. "NHN", "CBN", "GPH", "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN375", "SN395" manufactured by Toto Kasei Co., Ltd. , "LA7052", "LA7054", and "LA3018" manufactured by DIC Corporation.

The active ester curing agent is not particularly limited, but generally contains ester groups with high reactivity such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds in one molecule. A compound having two or more is preferably used. The active ester curing agent is preferably one 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. Particularly from the viewpoint of improving heat resistance, active ester curing agents obtained from a carboxylic acid compound and a hydroxy compound are preferred, and active ester curing agents obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound are more preferred. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenolic compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m- Cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, Examples include benzenetriol, dicyclopentadienyl diphenol, and phenol novolak.

Specifically, active ester compounds containing a dicyclopentadienyl diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing an acetylated product of phenol novolak, and active ester compounds containing a benzoylated product of phenol novolak are preferable. Among these, active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadienyl diphenol structure are more preferable.

Commercially available active ester curing agents include "EXB9451," "EXB9460," "EXB9460S," and "HPC-8000-65T" (manufactured by DIC Corporation) as active ester compounds containing a dicyclopentadienyl diphenol structure. ), "EXB9416-70BK" (manufactured by DIC Corporation) as an active ester compound containing a naphthalene structure, "DC808" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing an acetylated product of phenol novolac, Examples of active ester compounds containing benzoylated compounds include "YLH1026" (manufactured by Mitsubishi Chemical Corporation).

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

Examples of cyanate ester curing agents include bisphenol A dicyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene cyanate)), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4, 4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate) phenylpropane, 1,1-bis(4-cyanate phenylmethane), bis(4-cyanate-3,5- difunctional cyanate resins such as dimethylphenyl)methane, 1,3-bis(4-cyanatophenyl-1-(methylethylidene))benzene, bis(4-cyanatophenyl)thioether, and bis(4-cyanatophenyl)ether; Examples include polyfunctional cyanate resins derived from phenol novolacs and cresol novolaks, and prepolymers in which these cyanate resins are partially triazine-formed. Specific examples of cyanate ester curing agents include "PT30", "PT30S" and "PT60" (all phenol novolac type polyfunctional cyanate ester resins), "BA230" (bisphenol A dicyanate) manufactured by Lonza Japan Co., Ltd. Examples include prepolymers that are partially or entirely triazinated to form trimers.

Specific examples of carbodiimide curing agents include "V-03" and "V-07" manufactured by Nisshinbo Chemical Co., Ltd.

In the present invention, the curing agent (b) preferably contains one or more selected from phenolic curing agents, cyanate ester curing agents, and active ester curing agents, including triazine structure-containing phenolic resins, triazine structure-containing phenolic resins, and triazine structure-containing phenolic resins. It is more preferable that the composition contains one or more selected from alkylphenol resin, cyanate ester curing agent, and active ester curing agent.

The content of the curing agent (b) in the resin composition is not particularly limited, but from the viewpoint of obtaining an insulating layer with high peel strength and low dielectric loss tangent, it is preferably 0.1% by mass or more, more preferably 1% by mass or more. It is. (b) The upper limit of the content of the curing agent is not particularly limited as long as the effects of the present invention can be achieved, but it is preferably 30% by mass or less, more preferably 25% by mass or less.
Therefore, the content of the curing agent (b) in the resin composition is preferably 0.1 to 30% by mass, more preferably 1 to 25% by mass.

The quantitative ratio of (a) epoxy resin and (b) curing agent is [total number of epoxy groups in (a) epoxy resin]:[total number of reactive groups in (b) curing agent], and is 1: The range is preferably from 0.2 to 1:2, more preferably from 1:0.3 to 1:1.5, even more preferably from 1:0.4 to 1:1. Here, the reactive group of the curing agent is an active hydroxyl group, an active ester group, etc., and differs depending on the type of curing agent. The total number of epoxy groups in an epoxy resin is the sum of the solid mass of each epoxy resin divided by the epoxy equivalent, and the total number of reactive groups in a curing agent is the sum of the solid mass of each epoxy resin divided by the epoxy equivalent. This is the sum of the solid mass of the curing agent divided by the reactive group equivalent for all curing agents. By setting the ratio of the epoxy resin to the curing agent within this range, the heat resistance of the cured product of the resin composition is further improved.

(c) Inorganic filler The material of the inorganic filler is not particularly limited, but examples include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrocarbon Talcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, Examples include bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silica is particularly suitable. Moreover, as the silica, spherical silica is preferable. One type of inorganic filler may be used alone, or two or more types may be used in combination. Examples of commercially available inorganic fillers include "SO-C2", "SO-C1", and "SO-C4" manufactured by Admatex Co., Ltd.

The average particle size of the inorganic filler is not particularly limited, but from the viewpoint of obtaining an insulating layer with small surface roughness and improving the ability to form fine wiring, it is preferably 5 μm or less, more preferably 4 μm or less, and even more preferably 3 μm or less. Even more preferred is 1 μm or less, 0.7 μm or less, 0.5 μm or less, or 0.3 μm or less. On the other hand, when forming a resin varnish using a resin composition, from the viewpoint of obtaining a resin varnish that has an appropriate viscosity and good handling properties, and from the viewpoint of preventing an increase in the melt viscosity of the resin sheet, inorganic fillers are used. The average particle diameter is preferably 0.01 μm or more, more preferably 0.03 μm or more, and even more preferably 0.05 μm or more, 0.07 μm or more, or 0.1 μm or more. Therefore, the average particle size of the inorganic filler (c) in the resin composition is preferably 0.5 μm or less, or 0.3 μm or less.

The average particle size of the inorganic filler can be measured by a laser diffraction/scattering method based on Mie scattering theory. Specifically, it can be measured by creating the particle size distribution of the inorganic filler on a volume basis using a laser diffraction scattering particle size distribution measuring device, and using the median diameter as the average particle size. As the measurement sample, one in which an inorganic filler is dispersed in water using ultrasonic waves can be preferably used. As the laser diffraction scattering particle size distribution measuring device, "LA-500" manufactured by Horiba, Ltd., etc. can be used.

Inorganic fillers include aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, organosilazane compounds, and titanate coupling agents from the viewpoint of improving moisture resistance and dispersibility. It is preferable that the surface be treated with one or more surface treating agents such as. Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. and "KBM803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. Silane), Shin-Etsu Chemical Co., Ltd.'s "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM103" (phenyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM-4803" manufactured by Shin-Etsu Chemical Co., Ltd. (long-chain epoxy type) silane coupling agents), etc.

The degree of surface treatment by the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. The amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg/m ² or more, more preferably 0.1 mg/m ² or more, and 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 preventing an increase in the melt viscosity of the resin varnish or the melt viscosity in sheet form, it is preferably 1 mg/m ² or less, more preferably 0.8 mg/m ² or less, and even more preferably 0.5 mg/m ² or less. preferable.

The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (for example, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler whose surface has been treated with a surface treatment agent, and the mixture is subjected to ultrasonic cleaning at 25° C. for 5 minutes. After removing the supernatant liquid 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., etc. can be used.

The content of the inorganic filler (c) in the resin composition is preferably 80% by mass or less, more preferably 70% by mass or less, from the viewpoint of obtaining an insulating layer on which fine wiring can be formed. The lower limit of the content of the inorganic filler (c) in the resin composition is not particularly limited, and may be 5% by mass or more, 10% by mass or more, 20% by mass or more, etc.

In addition to the above (a), (b), and (c), the resin composition may also contain a thermoplastic resin, a curing accelerator, a flame retardant, and an organic filler such as rubber particles.

-Thermoplastic resin-
Examples of thermoplastic resins include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyether sulfone resin, polyphenylene ether resin, polycarbonate resin, and polyether. Examples include thermoplastic resins such as ether ketone resins and polyester resins, and among these, phenoxy resins are preferred. The thermoplastic resins may be used alone or in combination of two or more.

The weight average molecular weight of the thermoplastic resin in terms of polystyrene is preferably in the range of 5,000 to 100,000, more preferably in the range of 10,000 to 60,000, even more preferably in the range of 20,000 to 60,000. The weight average molecular weight of the thermoplastic resin in terms of polystyrene is measured by gel permeation chromatography (GPC). Specifically, the weight average molecular weight of the thermoplastic resin in terms of polystyrene was measured using an LC-9A/RID-6A manufactured by Shimadzu Corporation as a measuring device and a Shodex K-800P/K- manufactured by Showa Denko Co., Ltd. as a column. It can be calculated by measuring 804L/K-804L at a column temperature of 40° C. using chloroform or the like as a mobile phase, and using a standard polystyrene calibration curve.

Examples of phenoxy resins include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, and terpene. Examples include phenoxy resins having one or more types of skeletons selected from the group consisting of a skeleton and a trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. One type of phenoxy resin may be used alone, or two or more types may be used in combination. Specific examples of phenoxy resins include "1256" and "4250" (both phenoxy resins containing bisphenol A skeleton), "YX8100" (phenoxy resin containing bisphenol S skeleton), and "YX6954" (both manufactured by Mitsubishi Chemical Corporation). Bisphenolacetophenone skeleton-containing phenoxy resin), and in addition, "FX280" and "FX293" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., "YL6954BH30", "YL7553", "YL7769BH30" manufactured by Mitsubishi Chemical Corporation, Examples include "YL6794," "YL7213," "YL7290," and "YL7482."

Examples of the polyvinyl acetal resin include polyvinyl formal resin and polyvinyl butyral resin, with polyvinyl butyral resin being preferred. Specific examples of polyvinyl acetal resins include Denka Butyral 4000-2, Denka Butyral 5000-A, Denka Butyral 6000-C, and Denka Butyral 6000-EP manufactured by Denki Kagaku Kogyo Co., Ltd. , S-LEC BH series, BX series, KS series, BL series, BM series, etc. manufactured by Sekisui Chemical Co., Ltd.

Specific examples of polyimide resins include "Ricacoat SN20" and "Ricacoat PN20" manufactured by Shin Nippon Chemical Co., Ltd. Specific examples of polyimide resins include linear polyimides obtained by reacting bifunctional hydroxyl group-terminated polybutadiene, diisocyanate compounds, and tetrabasic acid anhydrides (polyimide described in JP-A No. 2006-37083), polysiloxane skeletons, etc. Examples include modified polyimides such as polyimides containing polyimides (polyimides described in JP-A-2002-12667 and JP-A-2000-319386, etc.).

Specific examples of the polyamide-imide resin include "Viromax HR11NN" and "Viromax 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 Co., Ltd.

A specific example of the polyether sulfone resin includes "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

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

Among these, phenoxy resin and polyvinyl acetal resin are preferred as the thermoplastic resin from the viewpoint of obtaining an insulating layer with lower surface roughness and better adhesion to the conductor layer in combination with other components. Therefore, in one preferred embodiment, the thermoplastic resin component includes one or more selected from the group consisting of phenoxy resin and polyvinyl acetal resin.

From the viewpoint of appropriately adjusting the melt viscosity of the resin composition, the content of the thermoplastic resin in the resin composition is preferably 0% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, More preferably, it is 1% by mass to 8% by mass.

-Curing accelerator-
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, etc. Curing accelerators and imidazole-based curing accelerators are preferred, and amine-based curing accelerators and imidazole-based curing accelerators are more preferred. The curing accelerator may be used alone or in combination of two or more.

Examples of the phosphorus curing accelerator include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate. , tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate and the like, with triphenylphosphine and tetrabutylphosphonium decanoate being preferred.

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

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

As the imidazole curing accelerator, commercially available products may be used, such as "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, trimethylguanidine, Tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0] Dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1 -allylbiguanide, 1-phenylbiguanide, 1-(o-tolyl)biguanide, etc., and dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene are preferred.

Examples of the metal hardening accelerator include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. Examples thereof include organic zinc complexes such as , organic iron 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, and zinc stearate.

The content of the curing accelerator in the resin composition is not particularly limited, but it is preferably used in a range of 0.02% by mass to 3% by mass.

-Flame retardants-
The resin composition may also contain a flame retardant. Examples of the flame retardant include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, and metal hydroxides. One type of flame retardant may be used alone, or two or more types may be used in combination.

As the flame retardant, commercially available products may be used, such as "HCA-HQ" manufactured by Sanko Co., Ltd., and the like.

The content of the flame retardant in the resin composition is not particularly limited, but is preferably 0.5% to 20% by mass, more preferably 1% to 15% by mass, and even more preferably 1.5% to 10% by mass. % is more preferable.

-Organic filler-
The resin composition may further contain an organic filler. As the organic filler, any organic filler that can be used when forming an insulating layer of a printed wiring board may be used, and examples thereof include rubber particles, polyamide fine particles, silicone particles, and the like, with rubber particles being preferred.

As the rubber particles, commercially available products may be used, such as "AC3816N" manufactured by Aica Kogyo Co., Ltd., and the like.

The content of the organic filler in the resin composition is preferably 1% by mass to 20% by mass, more preferably 2% by mass to 10% by mass.

The resin composition may further contain a flame retardant and other additives other than the organic filler, if necessary. Examples of such other additives include an organic copper compound, an organic zinc compound, and an organic filler. Examples include organic metal compounds such as organic cobalt compounds, and resin additives such as organic fillers, thickeners, antifoaming agents, leveling agents, adhesion agents, and colorants.

<Manufacturing method of printed wiring board>
The method for producing a printed wiring board of the present invention includes the steps of: (A) laminating the resin composition layer of an adhesive film comprising a support and a resin composition layer so as to be bonded to one surface or both surfaces of an inner layer substrate; , (B) a step of thermosetting the resin composition layer to form an insulating layer, (C) a step of peeling off the support, and (D) a step of roughening the surface of the insulating layer.

(A) Process The (A) process is a lamination process in which an adhesive film is laminated on one or both surfaces of the inner layer substrate. The adhesive film includes a support and a resin composition layer containing a resin composition formed on the support. The resin composition contained in the resin composition layer is as described above.

(Resin composition layer)
The thickness of the resin composition layer is preferably 100 μm or less, more preferably 80 μm or less, still more preferably 50 μm or less, or 40 μm or less, from the viewpoint of making the insulating layer thinner. The lower limit of the thickness of the resin composition layer is not particularly limited, but can usually be 1 μm or more, 3 μm or more, 5 μm or more, 10 μm or more, etc. Therefore, the thickness of the resin composition layer is preferably 1 to 100 μm, more preferably 3 to 80 μm, and even more preferably 5 to 50 μm.

The minimum melt viscosity of the resin composition layer is preferably 5000 poise (500 Pa s) or less, more preferably 4000 poise (400 Pa s) or less, 3000 poise (300 Pa s) or less, 2000 poise or less, from the viewpoint of obtaining good circuit embedding property. (200 Pa·s) or less, or more preferably 1500 poise (150 Pa·s) or less. The lower limit of the minimum melt viscosity is preferably 600 poise (60 Pa·s) or more, more preferably 800 poise (80 Pa·s) or more, and even more preferably 900 poise (90 Pa·s) or more.

The lowest melt viscosity of the resin composition layer refers to the lowest viscosity that the resin composition layer exhibits when the resin of the resin composition layer is melted. In detail, when the resin composition layer is heated at a constant temperature increase rate to melt the resin, the melt viscosity decreases as the temperature rises in the initial stage, and then, after a certain point, the melt viscosity increases as the temperature rises. do. The minimum melt viscosity refers to the melt viscosity at such a minimum point. The minimum melt viscosity of the resin composition layer can be measured by a dynamic viscoelasticity method.

(Support)
Examples of the support include a film made of a plastic material, a metal foil, and a release paper, and a film made of a plastic material and a metal foil are preferred.

When using a film made of a plastic material as a support, examples of the plastic material include polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN"). ), polyesters such as polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylics such as polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether Examples include ketones and polyimides. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred, and inexpensive polyethylene terephthalate is particularly preferred.

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

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

Further, as the support, a support with a release layer having a release layer on the surface to be bonded to the resin composition layer may be used. Examples of the release agent used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. . A commercially available product may be used as the support with a release layer.

The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, more preferably in the range of 10 μm to 60 μm. In addition, when using the support body with a mold release layer, it is preferable that the thickness of the whole support body with a mold release layer is in the said range.

In the present invention, a support whose surface in contact with the resin composition layer has an arithmetic mean roughness Ra ₁ of 200 nm or more is used. By forming irregularities on the surface of the insulating layer with a dielectric loss tangent of 0.005 or less, which will be described later, using a support whose surface arithmetic mean roughness Ra ₁ is 200 nm or more, the arithmetic mean of the surface of the insulating layer after roughening treatment is The roughness _Ra2 becomes an appropriate value. The arithmetic mean roughness (Ra ₁ ) of the support surface can be measured using a non-contact surface roughness meter. A specific example of a non-contact surface roughness meter is "WYKO NT3300" manufactured by Beco Instruments.

The arithmetic mean roughness Ra ₁ of the surface of the support in contact with the resin composition layer is preferably 250 nm or more, more preferably 300 nm or more. The upper limit of the arithmetic mean roughness Ra ₁ of the surface of the support in contact with the resin composition layer is not particularly limited, but is preferably 1000 nm or less, more preferably 800 nm or less. Note that the support may have an arithmetic mean roughness of 200 nm or more on both sides. As the support having a surface arithmetic mean roughness Ra ₁ of 200 nm or more, commercially available products may be used, such as Teijin, which is a PET film having a release layer containing a non-silicone resin release agent as a main component. Examples include "U2-NR1" and "U4-NR1" manufactured by DuPont Film Co., Ltd., and "#26-X42" manufactured by Toray Industries, Inc.

For the adhesive film, for example, a resin varnish is prepared by dissolving the above-mentioned resin composition in an organic solvent, and this resin varnish is applied onto a support using a die coater or the like, and further dried to form a resin composition layer. It can be manufactured by forming.

Examples of organic solvents 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. Examples include carbitols, aromatic hydrocarbons such as toluene and xylene, amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone. One type of organic solvent may be used alone, or two or more types may be used in combination.

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

In the adhesive film, a protective film similar to the support can be further laminated on the surface of the resin composition layer that is not bonded to the support (ie, the surface opposite to the support). 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 prevent dust and the like from adhering to the surface of the resin composition layer and from scratching it. The adhesive film can be wound up into a roll and stored. If the adhesive film has a protective film, it can be used by peeling off the protective film.

Furthermore, in the present invention, for example, after forming a resin composition layer on a protective film, a support may be laminated on the resin composition layer to produce an adhesive film.

[Inner layer board]
(A) The interior substrate used in the process is mainly a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, etc., or a pattern is processed on one or both sides of the substrate. A circuit board on which a conductive layer (circuit) is formed. Further, when manufacturing a printed wiring board, an inner layer circuit board, which is an intermediate product on which an insulating layer and/or a conductive layer is to be further formed, is also included in the "inner layer substrate" as referred to in the present invention. If the printed wiring board is a circuit board with built-in components, an inner layer board with built-in components may be used.

The inner layer substrate and the adhesive film can be laminated, for example, by heat-pressing the adhesive film onto the inner layer substrate from the support side. When the adhesive film is provided with a protective film, the member for heat-pressing the adhesive film to the inner substrate (hereinafter also referred to as "heat-pressing member") may be, for example, a heated metal plate (SUS mirror plate, etc.) or Examples include metal rolls (SUS rolls). It should be noted that, rather than pressing the thermocompression bonding member directly onto the adhesive film, it is preferable to press it through an elastic material such as heat-resistant rubber so that the adhesive film sufficiently follows the surface irregularities of the inner layer substrate.

The inner layer substrate and the adhesive film may be laminated by a vacuum lamination method. In the vacuum lamination method, the heat-pressing temperature is preferably in the range of 60°C to 160°C, more preferably 80°C to 140°C, and the heat-pressing pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably 0. The pressure is in the range of .29 MPa to 1.47 MPa, and the heat-pressing 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 of 26.7 hPa or less.

Lamination can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminators include a vacuum pressure laminator manufactured by Meiki Seisakusho Co., Ltd. and a vacuum applicator manufactured by Nichigo Morton Co., Ltd.

After lamination, the laminated adhesive films may be smoothed under normal pressure (atmospheric pressure), for example, by pressing a thermocompression bonding member from the support side. The pressing conditions for the smoothing treatment can be the same as the conditions for the heat-pressing of the lamination described above. The smoothing process can be performed using a commercially available laminator. Note that the lamination and smoothing treatment may be performed continuously using the above-mentioned commercially available vacuum laminator.

(B) Process The (B) process is a process of thermally curing the adhesive film laminated on the inner layer substrate in the (A) process to form an insulating layer.

The thermosetting conditions for the resin composition layer are not particularly limited, and conditions that are normally employed when forming an insulating layer of a printed wiring board may be used.

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

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

The dielectric loss tangent of the insulating layer formed by thermosetting the resin composition layer (resin composition) is 0.005 or less. The dielectric loss tangent of the insulating layer is preferably 0.0045 or less from the viewpoint of reducing loss of electrical signals. The lower limit of the dielectric loss tangent of the insulating layer is not particularly limited, but may be 0.001 or more, 0.003 or more, etc.

(C) Process (C) Process is a peeling process of peeling off the support. In the present invention, after the resin composition layer is thermally cured to form the insulating layer, the step (C) of peeling off the support is performed, so that the surface roughness of the insulating layer becomes appropriate.

After performing the step (C) and before performing the step (D) described later, a step [(C') step] of drilling a hole in the insulating layer may be performed. Holes such as via holes and through holes can be formed in the insulating layer by the step of drilling the insulating layer [(C') step]. The step (C') may be carried out using, for example, a drill, laser, plasma, etc., depending on the composition of the resin composition used to form the insulating layer. The size and shape of the hole may be determined as appropriate depending on the design of the printed wiring board.

(D) Process The (D) process is a roughening process of roughening the surface of the insulating layer. In the present invention, step (D) is performed such that the arithmetic mean roughness Ra ₂ of the surface of the insulating layer after performing step (D) is 200 nm to 800 nm.

In the step (D), the roughening treatment procedure and conditions are not particularly limited, and known procedures and conditions commonly used in forming an insulating layer of a printed wiring board can be adopted. For example, the insulating layer can be roughened by performing a swelling treatment using a swelling liquid, a roughening treatment using an oxidizing agent, and a neutralization treatment using a neutralizing liquid in this order. The swelling liquid is not particularly limited, but includes alkaline solutions, surfactant solutions, etc., preferably alkaline solutions, and more preferably sodium hydroxide solutions and potassium hydroxide solutions. Examples of commercially available swelling liquids include "Swelling Dip Securigance P" and "Swelling Dip Securigance SBU" manufactured by Atotech Japan Co., Ltd. Swelling treatment with a swelling liquid is not particularly limited, but can be carried out, for example, by immersing the insulating layer in a 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 cured product in a swelling liquid at 40° C. to 80° C. for 5 minutes to 15 minutes. The oxidizing agent is not particularly limited, but includes, for example, 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 permanganic acid solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60° C. to 80° C. for 10 minutes to 30 minutes. Further, the concentration of permanganate in the alkaline permanganic acid 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 "Dosing Solution Securigance P" manufactured by Atotech Japan Co., Ltd. Further, as the neutralizing liquid, an acidic aqueous solution is preferable, and a commercially available product includes, for example, "Reduction Solution Securigant P" manufactured by Atotech Japan Co., Ltd. The treatment with the neutralizing liquid can be carried out by immersing the treated surface, which has been roughened with an oxidizing agent, in the neutralizing liquid at 30° C. to 80° C. for 5 minutes to 30 minutes. From the viewpoint of workability, it is preferable to immerse the object that has been roughened with an oxidizing agent in a neutralizing solution at 40° C. to 70° C. for 5 minutes to 20 minutes.

In the present invention, the arithmetic mean roughness Ra ₂ of the surface of the insulating layer after step (D) is 200 nm to 800 nm. The arithmetic mean roughness Ra ₂ of the surface of the insulating layer after the step (D) is preferably from 200 nm to 700 nm, more preferably from 250 to 650 nm, from the viewpoint of improving the adhesion of the dry film. The arithmetic mean roughness (Ra) of the surface of the insulating layer can be measured using a non-contact surface roughness meter. A specific example of a non-contact surface roughness meter is "WYKO NT3300" manufactured by Beaco Instruments.

The difference between the arithmetic mean roughness Ra ₁ of the surface of the support in contact with the resin composition layer and the arithmetic mean roughness Ra ₂ of the surface of the insulating layer after step (D) is preferably 100 nm or less. , more preferably 800 nm or less.

(E) Process The method for manufacturing a printed wiring board of the present invention may include the step (E) of forming a conductor layer having a wiring pattern (pitch) of 20 μm or less [(E) process].

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

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

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

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

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

In the step (E), the wiring pattern is preferably 20 μm or less, more preferably 18 μm or less, even more preferably 16 μm or less, and even more preferably 15 μm or less.

In the present invention, dry film resist adhesion after roughening treatment is excellent. In one embodiment, even if the wiring is as fine as L (line)/S (space) = 6/10, the resist does not peel off after exposure and development. Note that in this case, the pitch is 16 μm.

[Printed wiring board]
The printed wiring board of the present invention includes an insulating layer having a dielectric loss tangent of 0.005 or less and a surface arithmetic mean roughness Ra ₂ of 200 nm or more. The printed wiring board of the present invention can be manufactured, for example, by the method for manufacturing a printed wiring board of the present invention described above.

[Semiconductor device]
The semiconductor device of the present invention is characterized in that it includes a printed wiring board manufactured by the method for manufacturing a printed wiring board of the invention described above or a printed wiring board of the invention described above. The semiconductor device of the present invention can be manufactured using the printed wiring board obtained by the manufacturing method of the present invention or the printed wiring board of the present invention.

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

The semiconductor device of the present invention can be manufactured by mounting components (semiconductor chips) on conductive parts of a printed wiring board. A "conducting location" is a "location on a printed wiring board that transmits electrical signals," and the location may be on the surface or embedded. 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 when manufacturing the semiconductor device of the present invention is not particularly limited as long as the semiconductor chip functions effectively, but specifically, wire bonding mounting method, flip chip mounting method, non-bump mounting method, etc. Examples include a mounting method using a build-up layer (BBUL), a mounting method using an anisotropic conductive film (ACF), and a mounting method using a non-conductive film (NCF). Here, "a mounting method using a bumpless buildup layer (BBUL)" refers to a "mounting method in which a semiconductor chip is directly embedded in a recess of a printed wiring board and the semiconductor chip and wiring on the printed wiring board are connected." It is.

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples. In the following description, "parts" and "%" mean "parts by mass" and "% by mass," respectively, unless otherwise specified.

[Preparation of adhesive film]
Adhesive films 1 to 4 used in Examples and Comparative Examples were produced by the following method.

<Production Example 1: Production of adhesive film 1 used in Example 1>
Bisphenol type epoxy resin (Nippon Steel Chemical Co., Ltd. "ZX1059", 1:1 mixture of bisphenol A and bisphenol F types, epoxy equivalent 169) 5 parts, biphenyl type epoxy resin (Nippon Kayaku Co., Ltd.) 15 parts of "NC3000L, epoxy equivalent: 280" and 20 parts of a dicyclopentadiene type epoxy resin ("HP7200H", manufactured by DIC Corporation, epoxy equivalent: 275) were dissolved in 15 parts of solvent naphtha with stirring while heating. After cooling to room temperature (25°C), 5 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation), active ester curing agent ("HPC8000-65T" manufactured by DIC Corporation), and 65 mass of non-volatile components were added thereto. % toluene solution), 5 parts of curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with solid content of 10% by mass), phenylaminosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573") ”) was mixed with 95 parts of spherical silica (average particle size: 0.5 μm, “SOC2” manufactured by Admatex Co., Ltd., carbon content per unit area: 0.39 mg/m ² ), and mixed with a high-speed rotating mixer. Resin varnish 1 was produced by uniformly dispersing it. Next, the resin composition after drying was applied onto the release surface of a polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm, arithmetic mean roughness Ra ₁ 250 nm). Resin varnish 1 was applied uniformly so that the thickness of the material layer was 30 μm, and dried at 80 to 120° C. (average 100° C.) for 4 minutes to prepare adhesive film 1.

<Production Example 2: Production of adhesive film 2 used in Example 2>
The polyethylene terephthalate film with release treatment used in Production Example 1 (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm) was replaced with the polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm). Adhesive film 2 was produced in the same manner as in Production Example 1, except that the adhesive film was changed to a releasable PET "U4-NR1" (manufactured by ), thickness 38 μm).

<Production Example 3: Production of adhesive film 3 used in Example 3>
Adhesive film 3 was produced in the same manner as in Production Example 1, except that Resin Varnish 2 produced by the following method was used in place of Resin Varnish 1 used in Production Example 1.

(Preparation of resin varnish 2)
5 parts of liquid naphthalene-type epoxy resin (epoxy equivalent: 144, "HP4032SS" manufactured by DIC Corporation), 25 parts of naphthol-type epoxy resin ("ESN475V", manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., epoxy equivalent: 331), and 30 parts of solvent naphtha. The mixture was heated and dissolved while stirring. After cooling to room temperature (25°C), 5 parts of phenoxy resin (“YX7553BH30” manufactured by Mitsubishi Chemical Corporation) and a prepolymer of bisphenol A dicyanate (“BA230S75” manufactured by Lonza Japan Co., Ltd.), cyanate equivalent: approx. 232, MEK solution with nonvolatile content of 75% by mass) 20 parts, phenol novolak type polyfunctional cyanate ester resin (“PT30S” manufactured by Lonza Japan Co., Ltd., cyanate equivalent: about 133, MEK solution with nonvolatile content of 85% by mass), 7 parts, 1 part of curing accelerator (4-dimethylaminopyridine, MEK solution with a solid content of 2.5% by mass), curing accelerator (manufactured by Tokyo Kasei Co., Ltd., cobalt (III) acetylacetonate (Co (III) acac), 3 parts of MEK solution with a solid content of 1% by mass), spherical silica surface-treated with a phenylaminosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573") (average particle size 0.5 μm, manufactured by Ad Co., Ltd.) Resin varnish 2 was prepared by mixing 110 parts of "SOC2" manufactured by Matex (carbon content per unit area: 0.39 mg/m ² ) and uniformly dispersing the mixture using a high-speed rotating mixer.

<Production Example 4: Production of adhesive film 4 used in Example 4>
The polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm) used in Production Example 3 was replaced with the polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm). Adhesive film 4 was produced in the same manner as in Production Example 3, except that the adhesive film was changed to a releasable PET "U4-NR1" (manufactured by ), 38 μm thick).

<Production Example 5: Production of adhesive film 5 used in Comparative Examples 1 and 2>
The polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm) used in Production Example 1 was replaced with the polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd.) Adhesive film 5 was produced in the same manner as in Production Example 1, except that the film was made of mold release PET "X3", the arithmetic mean roughness Ra ₁ was 20 μm, and the thickness was 31 μm).

<Production Example 6: Production of adhesive film 6 used in Comparative Examples 3 and 4>
The polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd., release PET "U2-NR1", thickness 38 μm) used in Production Example 3 was replaced with the polyethylene terephthalate film with release treatment (manufactured by Teijin DuPont Films Ltd.) Adhesive film 6 was produced in the same manner as in Production Example 3, except that the adhesive film 6 was made of mold release PET "X3" (thickness: 31 μm).

Table 1 shows the composition of the nonvolatile components of the resin varnish used to prepare the adhesive film.

[Evaluation test]
Using adhesive films 1 to 6 produced by the above method, printed wiring boards of Examples and Comparative Examples were produced by the following method and evaluated.

<Preparation of evaluation board A for arithmetic mean roughness (Ra _binary ) measurement and sample for dry film resist adhesion investigation>
(1) Surface treatment of inner layer substrate A glass cloth-based epoxy resin double-sided copper-clad laminate (copper foil thickness 18 μm, board thickness 0.4 mm, R1515A manufactured by Matsushita Electric Works Co., Ltd.) was used as the inner layer substrate. The copper surface was roughened by etching by 1 μm using CZ8101 manufactured by MEC Corporation.

(2) Adhesive film lamination (adhesive film lamination)
Each adhesive film was laminated on both sides of the roughened epoxy resin double-sided copper-clad laminate using a batch vacuum pressure laminator MVLP-500 (manufactured by Meiki Seisakusho Co., Ltd.). Lamination was carried out by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then press-bonding at 100° C. and a pressure of 0.74 MPa for 30 seconds.

(3) Formation of insulating layer and peeling of support For Examples 1 to 4 and Comparative Examples 1 and 3, the laminate on which the adhesive film was laminated was heated at 100°C for 30 minutes, and then heated at 180°C for 30 minutes. After the resin composition layer was cured under curing conditions to form an insulating layer, the release PET film (support) was peeled off.
For Comparative Examples 2 and 4, after peeling off the release PET film (support) from the adhesive film laminated to the laminate, the laminate was heated at 100°C for 30 minutes, and then cured at 180°C for 30 minutes. The resin composition layer was cured under the following conditions to form an insulating layer.

(4) Roughening treatment Each laminate with an insulating layer formed thereon was treated with a swelling liquid, Swelling Dip Securigant P (manufactured by Atotech Japan Co., Ltd.) containing diethylene glycol monobutyl ether (glycol ethers, sodium hydroxide). aqueous solution) for 5 minutes at 60°C. Next, Concentrate Compact P (KMnO ₄ : 60 g/L, NaOH: 40 g/L aqueous solution) manufactured by Atotech Japan Co., Ltd. was used as a roughening liquid, and each laminate was heated to 80°C in the roughening liquid. Soaked for 20 minutes. Next, Reduction Shoryushin Securigant P (sulfuric acid aqueous solution) manufactured by Atotech Japan Co., Ltd. was used as a neutralizing solution, and each laminate was immersed in the neutralizing solution at 40° C. for 5 minutes. Next, the laminate was dried at 80° C. for 30 minutes, and then the board was designated as evaluation board A.

(5) Plating by semi-additive method Evaluation board A was plated to form a conductor layer. Specifically, evaluation board A was immersed in an electroless plating solution containing PdCl ₂ at 40° C. for 5 minutes, and then in an electroless copper plating solution at 25° C. for 20 minutes. The sample that was annealed by heating at 150° C. for 30 minutes was used as a sample for investigating dry film resist adhesion.

<Evaluation test>
(1) Measurement of arithmetic mean roughness (Ra ₂ ) of the insulating layer after roughening treatment The arithmetic mean roughness Ra ₂ of the surface of the insulating layer of evaluation board A was measured using a non-contact surface roughness meter (manufactured by Beco Instruments). Ra ₂ was determined using a VSI contact mode using a 50x lens (WYKO NT3300) with a measurement range of 121 μm x 92 μm. It was measured by calculating the average value of each 10 points, and the results are shown in Table 2. Table 2 also shows the arithmetic mean roughness Ra ₁ of the resin composition layer side surface of each release PET film used as a support (in Table 2, the arithmetic mean roughness Ra ₁ of the surface of the support (described as (nm)). The arithmetic mean roughness Ra ₁ of the support was also measured under the same conditions as the arithmetic mean roughness Ra ₂ of the insulating layer.

(2) Measurement of dielectric loss tangent The sample for dielectric loss tangent measurement was cut into test pieces with a width of 2 mm and a length of 80 mm. The dielectric loss tangent (tan δ) was measured by the cavity resonance method using Network Analyzer E8362B manufactured by Co., Ltd. at a measurement frequency of 5.8 GHz. Measurements were performed on two test pieces, and the average value was calculated and shown in Table 2.

(3) Evaluation of dry film resist adhesion (DFR adhesion) Dry film resist RY5725 manufactured by Hitachi Chemical Co., Ltd. was laminated with a roll laminator on the dry film resist adhesion investigation sample, and L/S = 6/ The presence or absence of resist peeling after exposure and development was confirmed with an optical microscope for portions No. 10, and those in which no resist peeling was observed were evaluated as ○, and those in which resist peeling was observed were evaluated as ×, and the results are shown in Table 2. It was shown to.

Table 2 also lists the types of resin varnishes used in the Examples and Comparative Examples, the type of release PET film used as a support, and the conditions for curing the resin composition layer. Regarding the curing conditions, "yes" was written for those that were cured with the support attached, and "no" was written for those that were cured with the support removed.

Claims (6)

An adhesive film for printed wiring boards, comprising a support and a resin composition layer,
The arithmetic mean roughness Ra ₁ of the side of the support in contact with the resin composition layer is 200 nm or more,
The dielectric loss tangent of the insulating layer formed by thermosetting the resin composition layer is 0.005 or less,
The support is a film made of a plastic material or a film made of a plastic material with a release layer,
The resin composition layer is heated at 100°C for 30 minutes, then thermally cured at 180°C for 30 minutes to form an insulating layer, the support is peeled off, and the surface of the insulating layer is soaked in a swelling liquid at 60°C. The surface of the insulating layer was The arithmetic mean roughness Ra ₂ is 200 nm to 800 nm, and the swelling liquid is glycol ethers, an aqueous solution of sodium hydroxide (Swelling Dip Securigant P manufactured by Atotech Japan Co., Ltd.), and a roughening liquid. is an aqueous solution of KMnO ₄ : 60 g/L and NaOH: 40 g/L (Concentrate Compact P, manufactured by Atotech Japan Co., Ltd.), and the neutralizing liquid is an aqueous solution of sulfuric acid (Reduction Solution Securigant, manufactured by Atotech Japan Co., Ltd.). P) and
The minimum melt viscosity of the resin composition layer is 60 to 500 Pa·s,
adhesive film. The adhesive film according to claim 1, wherein the surface of the support in contact with the resin composition layer has an arithmetic mean roughness Ra ₁ of 250 nm or more. The adhesive film according to claim 1 or 2, wherein the surface of the support in contact with the resin composition layer has an arithmetic mean roughness Ra ₁ of 300 nm or more. The adhesive film according to any one of claims 1 to 3, wherein the resin composition forming the resin composition layer contains an epoxy resin, a curing agent, and an inorganic filler. 5. The adhesive film of claim 4, wherein the curing agent comprises an active ester curing agent. Any one of claims 1 to 5 , wherein the difference between the arithmetic mean roughness Ra ₂ of the surface of the insulating layer and the arithmetic mean roughness Ra ₁ of the surface of the support in contact with the resin composition layer is 100 nm or less. The adhesive film according to item 1.