JP2014210936A - Resin composition, resin cured product, wiring board, and method for manufacturing wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulating resin, a wiring board and a method for manufacturing the wiring board which can easily exhibit high adhesive strength to a wiring conductor even when an uneven shape on the surface of an insulating resin layer is small.SOLUTION: A resin composition contains (A) an epoxy resin having two or more epoxy groups in one molecule, (B) an ultraviolet active type ester group-containing compound, (C) isocyanate silane, and (D) an epoxy resin curing accelerator.

Description

  The present invention relates to a resin composition, a cured resin, a wiring board, and a method for manufacturing a wiring board. More specifically, the present invention relates to an insulating resin, a wiring board, and a method for manufacturing a wiring board that can exhibit a high adhesive force to a wiring conductor even when the uneven shape on the surface of the insulating resin layer is small.

  As electronic devices are further reduced in size, weight, and functionality, LSIs and chip components have been highly integrated, and their forms are rapidly changing to multiple pins and downsizing. For this reason, in order to improve the mounting density of electronic components, development of a wiring board that can cope with miniaturization is underway. As such a wiring board, there is a build-up type wiring board that uses insulating resin that does not contain glass cloth instead of prepreg, and forms a wiring layer while connecting only necessary parts with via holes, making it lighter and smaller It is becoming mainstream as a method suitable for miniaturization.

In this build-up type wiring board, first, an insulating resin layer is formed on a substrate having a circuit. And after hardening an insulating resin layer, in order to ensure the adhesive force with a wiring conductor, the insulating resin layer surface is immersed in an oxidizing process liquid, and a roughening process is performed. Next, electroless plating is performed by pre-plating treatment. Furthermore, after forming a resist pattern on the electroless plating layer and thickening by electroplating, the resist pattern is peeled off and the electroless plating layer is removed to obtain a wiring board.
However, with the miniaturization of the wiring, the unevenness on the surface of the insulating resin layer formed by roughening the surface of the insulating resin layer causes a decrease in the yield of wiring formation. This is because the electroless metal plating layer bites into the irregularities on the surface of the insulating resin layer, making it difficult to remove and causing wiring shorts, and the resist pattern formation accuracy decreases due to the irregularities on the surface of the insulating resin layer. It is to do.

  Therefore, reducing the unevenness on the surface of the insulating resin layer is important for realizing fine wiring. However, if the unevenness is reduced, the adhesive force between the insulating resin layer and the electroless metal plating layer is reduced. It is necessary to improve. Further, as the oxidizing roughening liquid used for forming irregularities on the surface of the insulating resin layer, a strong alkaline liquid of sodium permanganate and sodium hydroxide is generally used. Sodium permanganate dissolves the resin under strong alkali. However, since 7-valent manganese is consumed in the oxidation treatment, it is necessary to regenerate manganese with an electrolytic regeneration device. In order to ensure insulation reliability and heat resistance of ordinary insulating resins, management of manganese is important because it is designed with increased resistance to the roughening solution. However, since the dissolved resin floats in the treatment liquid, the electrolytic regeneration of manganese is not in time, and the liquid needs to be frequently bathed. These add costs such as water washing treatment and waste liquid treatment, resulting in a cost increase.

As described above, the insulating resin layer used in the build-up type wiring board is required to have an adhesive force even if the unevenness is small.
Further, it is desirable that the adhesive strength between the insulating resin layer and the electroless metal plating layer is maintained as it is even when exposed to a high temperature for a long time, but the adhesive strength may be reduced due to copper oxidation or the like. On the other hand, the adhesive strength must be maintained, for example, by preventing oxidation of copper.

Various proposals have been made for these requirements. For example, in Patent Document 1, an insulating resin layer using a polyphenylene ether resin is irradiated with ultraviolet rays in the presence of oxygen to provide a conductor layer, and then heat-treated to form a circuit in the conductor layer or to form a circuit. A method of performing heat treatment later has been proposed (see Patent Document 1 and Claim 1). The technique discloses that the surface roughness of the insulating layer can be kept small, and the adhesion between the insulating layer and the conductor layer can be improved (see Patent Document 1, paragraph 0006).
Patent Document 2 discloses a technique for treating an insulating resin layer with an ultraviolet ray under an ozone solution. According to this technique, it is possible to suppress the plating catalyst from being excessively applied to the surface of the insulating layer while ensuring the adhesion between the wiring and the insulating layer, and to suppress the deterioration of the insulation resistance between the wirings. It is disclosed that it can be done (see Patent Document 2, Claim 1, Paragraph 0006).

JP 2004-214597 A JP 2005-5319 A

According to the technique disclosed in Patent Document 1 described above, the surface roughness of the insulating layer can be suppressed and the adhesion between the insulating layer and the conductor layer can be improved. There is no specific disclosure about the strength of the force, and the extent of the effect is unknown. In addition, the polyphenylene ether resin used as an insulating resin in Patent Document 1 is a xenon excimer lamp having a wavelength of 300 nm or less, which is different from an ultraviolet lamp generally used for post-exposure of a solder resist, or a low-pressure mercury lamp. There is a problem in manufacturing that must be used.
Further, in the technique disclosed in Patent Document 2, since no mention is made of the insulating resin composition, the degree of the effect is unknown. Moreover, the process of immersing in the ozone solution whose ozone concentration is 100 ppm or more is essential, and there exists a problem that operation is complicated.

  The present invention has been made under such circumstances. Even when the surface of the insulating resin layer has a small uneven shape, the present invention has a high adhesion to the wiring conductor and can be insulated even if left at a high temperature for a long time. A resin composition in which a resin layer maintains high adhesion to a wiring conductor, a cured resin obtained by curing the resin composition, a wiring board using the cured resin, and a method for manufacturing the wiring board The purpose is to provide.

As a result of intensive studies to achieve the above object, the present inventors use a resin composition containing an epoxy resin, a UV-active ester group-containing compound, an isocyanate silane, and an epoxy resin curing accelerator. It has been found that the above object can be achieved.
Further, an uncured resin layer is provided on a substrate having a circuit by using the resin composition, and the uncured resin layer is thermally cured and then subjected to a treatment of irradiating with ultraviolet rays on the cured resin layer. It has been found that a desired wiring board can be efficiently obtained by forming a wiring by a plating method.
The present invention has been completed based on such findings.

That is, the present invention
(1) (A) an epoxy resin having two or more epoxy groups in one molecule, (B) a UV-active ester group-containing compound, (C) an isocyanate silane, and (D) an epoxy resin curing accelerator Composition,
(2) A cured resin product obtained by thermally curing the resin composition according to (1) above and irradiating with ultraviolet rays;
(3) A wiring board in which a cured resin layer made of the resin cured product described in (2) above is disposed on a substrate having a circuit of a wiring conductor, and wiring is formed on the cured resin layer by plating, And (4) (a) a step of forming an uncured resin layer using the resin composition according to (1) above on a substrate having a circuit of a wiring conductor, and (b) thermosetting the uncured resin layer. The present invention provides a method for manufacturing a wiring board, comprising: a step of forming a cured resin layer by treatment with ultraviolet rays, and a step of (c) subjecting the cured resin layer to electroless plating.
In addition, since the cured resin layer in this invention has insulation, it may be called the "insulating resin layer" below.

  According to the present invention, even in a state where the uneven shape on the surface of the insulating resin layer is small, a high adhesive force is exerted on the wiring conductor, and a roughening liquid such as sodium permanganate is used to remove smear on the bottom of the via hole. Even if it processes, the roughening uneven | corrugated shape of the insulating resin layer surface is small, and the manufacturing method of the resin composition which can maintain the high adhesive force with respect to a wiring conductor, a wiring board, and a wiring board can be provided.

  The resin composition of the present invention comprises (A) an epoxy resin having two or more epoxy groups in one molecule, (B) an ultraviolet active ester group-containing compound, (C) an isocyanate silane, and (D) an epoxy resin cured. Contains an accelerator.

[Resin composition]
((A) Epoxy resin)
In the resin composition of the present invention, the epoxy resin used as the component (A) is not particularly limited as long as it has two or more epoxy groups in one molecule. For example, a cresol novolac type epoxy resin, Phenol novolac type epoxy resin, naphthol novolak type epoxy resin, biphenyl novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol T type epoxy resin, bisphenol Z type epoxy resin, tetrabromo Bisphenol A type epoxy resin, biphenyl type epoxy resin, tetramethyl biphenyl type epoxy resin, triphenyl type epoxy resin, tetraphenyl type epoxy resin, naphthol aralkyl type epoxy resin, naphthalene All aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, fluorene epoxy resin, an epoxy resin having a dicyclopentadiene skeleton, epoxy resins having an ethylenically unsaturated group in the backbone, and alicyclic epoxy resins. Moreover, you may use 2 or more types in combination from a viewpoint of insulation reliability or heat resistance.

((B) UV-active ester group-containing compound)
In the resin composition of the present invention, the UV-active ester group-containing compound as the component (B) is a compound containing an ester group that is activated by irradiation with UV light, and the epoxy resin as the component (A) is cured. It is a component that can also be used as an agent. More specifically, one or more ester groups are contained in one molecule, and the epoxy resin can be cured without containing a hydroxyl group. For example, aliphatic or aromatic carboxylic acid and aliphatic or aromatic And ester compounds obtained from group hydroxy compounds. Among these, an ester compound composed of an aliphatic carboxylic acid, an aliphatic hydroxy compound, or the like can increase the solubility in an organic solvent and the compatibility with an epoxy resin by including an aliphatic chain. On the other hand, an ester compound composed of an aromatic carboxylic acid or an aromatic hydroxy compound can improve the heat resistance of the resin composition by having an aromatic ring.

Preferred examples of the ultraviolet active ester group-containing compound include benzene, naphthalene, biphenyl, diphenylpropane, diphenylmethane, diphenyl ether, diphenylsulfone, benzophenone, etc., substituted by 2 to 4 hydrogen atoms of an aromatic ring with a carboxy group An aromatic carboxylic acid component selected from: a monohydric phenol compound in which one of the hydrogen atoms of the aromatic ring is substituted with a hydroxyl group, and a polyhydric phenol type in which 2 to 4 hydrogen atoms of the aromatic ring are substituted with a hydroxyl group An aromatic ester obtained by a condensation reaction of an aromatic carboxylic acid and a phenolic hydroxyl group can be mentioned using a mixture with a compound as a raw material.
Examples of monohydric phenol compounds include phenol, various cresols, α-naphthol, β-naphthol, and the like. Examples of polyhydric phenol compounds include hydroquinone, resorcin, catechol, 4,4′-biphenol, 4, 4'-dihydroxydiphenyl ether, bisphenol A, bisphenol F, bisphenol S, bisphenol Z, brominated bisphenol A, brominated bisphenol F, brominated bisphenol S, methylated bisphenol S, various dihydroxynaphthalenes, various dihydroxybenzophenones, various trihydroxybenzophenones And various tetrahydroxybenzophenones and phloroglycines.
On the other hand, examples of the aromatic carboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, and benzenetricarboxylic acid.
The ultraviolet-active ester group-containing compound may be a resin having one or more ester groups in one molecule, and is also commercially available. Examples include “EXB-9460”, “EXB-9460S”, “EXB-9470”, “EXB-9480”, “EXB-9420” manufactured by DIC Corporation, “BPN80” manufactured by Mitsui Chemicals, Inc. .
These ultraviolet active ester group-containing compounds may be used alone or in combination of two or more.

  In the resin composition of the present invention, the UV-active ester group-containing compound of the component (B) is contained in an amount of 0.95 to 1.25 equivalents relative to 1 equivalent of the epoxy of the (A) epoxy resin. It is preferable. If it is within this range, sufficient curability and heat resistance can be obtained.

The component (C) in the resin composition of the present invention is isocyanate silane. By using isocyanate silane in an insulating resin layer in a wiring board to be described later, high adhesiveness with copper can be secured when a wiring conductor is formed on the resin layer. Although the mechanism is not necessarily clear, in the process where the surface of copper wiring is oxidized by oxygen in the air, it is suppressed that copper is oxidized to copper oxide (CuO) by (C) isocyanate silane. It is presumed that many states of cuprous oxide (Cu ₂ O) are produced.
In addition, it is considered that the active ester group of the ultraviolet ray active ester group-containing compound (B) is decomposed to generate an OH group by the ultraviolet irradiation treatment described in detail later, but the OH group and isocyanate of isocyanate silane are combined. And it seems that the high adhesiveness of an insulating resin layer and copper is acquired because the terminal silane couple | bonds with Pd which is a plating catalyst.

  As the isocyanate silane used in the present invention, various types can be used. For example, isocyanate methyltrimethoxysilane, 2-isocyanatoethyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, 4-isocyanatobutyltrimethoxysilane, 5-isocyanatepentyltrimethoxysilane, isocyanatemethyltriethoxysilane, 2-isocyanateethyltriethoxysilane, 3-isocyanatepropyltriethoxysilane, 4-isocyanatobutyltriethoxysilane, 5-isocyanatepentyltriethoxysilane, isocyanatemethylmethyldimethoxy Sisilane, 2-isocyanatoethylethyldimethoxysilane, 3-isocyanatopropyltrimethoxysilane, 2- E sulfonyl imidazole or 3- isocyanatepropyltriethoxysilane, and the like. Of these, 3-isocyanatopropyltriethoxysilane or 2-phenylimidazole is particularly preferable from the viewpoint of suppressing oxidation of copper wiring and improving adhesive strength.

  The said isocyanate silane can be used individually by 1 type or in combination of 2 or more types, Moreover, isocyanate silane is 3 to 100 mass parts of ultraviolet active ester group containing compounds which are (B) components. It is preferable to contain in 20 mass parts. When the amount is 3 parts by mass or more, the above-described effects, in particular, the effect of suppressing the oxidation of the copper wiring can be sufficiently exhibited. On the other hand, the content of 20 parts by mass or less is preferable in that the resin and the isocyanate silane are sufficiently compatible. From the above viewpoint, the isocyanate silane is more preferably in the range of 3 to 15 parts by mass, and particularly preferably in the range of 3 to 10 parts by mass.

((D) Epoxy resin curing accelerator)
In the resin composition of this invention, there is no restriction | limiting in particular as an epoxy resin hardening accelerator of (D) component, The general hardening accelerator used for hardening of an epoxy resin can be used.
Specific examples of the curing accelerator include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 2-undecylimidazole, 1-cyanoethyl-2. -Imidazole compounds such as phenylimidazolium trimellitate; Organic phosphite compounds such as triphenylphosphine and tributylphosphine; Organic phosphite compounds such as trimethylphosphite and triethylphosphite; Ethyltriphenylphosphonium bromide and tetraphenylphosphonium Phosphonium salt compounds such as tetraphenylborate; Trialkylamines such as triethylamine and tributylamine; 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6- Amine compounds such as lis (dimethylaminomethyl) phenol, 1,8-diazabicyclo (5.4.0) -undecene-7 (hereinafter abbreviated as DBU), DBU and terephthalic acid, 2,6-naphthalenedicarboxylic acid, etc. And quaternary ammonium salt compounds such as tetraethylammonium chloride, tetrapropylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrahexylammonium bromide, and benzyltrimethylammonium chloride. These may be used individually by 1 type, and may be used in combination of 2 or more types.
Moreover, it is preferable that content of the said hardening accelerator in the resin composition of this invention is 0.02-3.0 mass parts with respect to 100 mass parts of (A) component epoxy resins. If it is 0.02 parts by mass or more, the epoxy resin is sufficiently cured and heat resistance can be maintained. On the other hand, if it is 3.0 parts by mass or less, the storage stability of the resin composition and the B stage can be maintained. The handleability of the resin composition is improved. From the above viewpoint, the content of the (D) curing accelerator is more preferably in the range of 0.1 to 2.0 parts by mass, and particularly preferably in the range of 0.3 to 1.5 parts by mass.

The resin composition of the present invention containing the components (A) to (D) described above can be thermally cured and irradiated with ultraviolet rays to form a cured resin, which can be developed for various uses. it can. Specifically, for example, as will be described in detail later, a cured resin layer made of the cured resin is disposed on a substrate having a circuit of a wiring conductor to form an insulating resin layer, and wiring is formed on the resin layer. A wiring board can be obtained by forming by plating.
The insulating resin layer obtained as described above exhibits a high adhesive force to the wiring conductor as described above, even though the uneven shape on the surface of the insulating resin layer is small.

The thermosetting conditions will be described later. Further, as the ultraviolet irradiation conditions, using a UV lamp emitting in the range of the maximum wavelength 300 to 450 nm, under atmospheric pressure, the amount of light is 1000~5000mJ / cm ² or so, so that preferably becomes 3000~4000mJ / cm ² In addition, it is desirable to irradiate ultraviolet rays.
The light quantity (mJ / cm ² ) is represented by “illuminance (mW / cm ² ) × irradiation time (seconds)”.

As described above, the insulating resin layer is not subjected to an uneven shape using a conventional roughening liquid such as sodium permanganate by performing ultraviolet irradiation treatment after the thermosetting treatment of the insulating resin layer. In addition, since high adhesive strength can be expressed with respect to the wiring conductor, it is possible to suppress a decrease in the yield of wiring formation, and it is possible to eliminate water washing processing and waste liquid processing by using a roughening liquid, which is advantageous in terms of cost. It is.
In addition, even if it is treated with a roughening solution such as sodium permanganate to remove smear at the bottom of the via hole, the roughened uneven shape is small and high adhesion to the wiring conductor can be secured. .
In addition, the temperature of the insulating resin layer at the time of ultraviolet irradiation is preferably about 50 to 80 ° C, and more preferably 60 to 70 ° C.

  In the resin composition of the present invention, an inorganic filler and various additive components, for example, a leveling agent, an antioxidant, a flame retardant, a thixotropic agent, a thickening agent, as necessary, as long as the object of the present invention is not impaired. An agent, a solvent, etc. can be contained.

[Inorganic filler]
Inorganic fillers are included for the purpose of suppressing the coefficient of thermal expansion and increasing the coating strength. For example, silica, fused silica, talc, alumina, aluminum hydroxide, barium sulfate, calcium hydroxide, aerosil, calcium carbonate. What is chosen from these can be used, and these may be used individually by 1 type and may be used in combination of 2 or more type. In addition, it is preferable to use silica from the viewpoint of dielectric properties and low thermal expansion, and the content thereof is preferably 5-35 vol% in the solid content of the resin composition excluding the solvent, and is preferably 10-30 vol%. More preferred. If it is 5 vol% or more, an increase in the thermal expansion coefficient and dielectric loss can be suppressed. On the other hand, if it is 35 vol% or less, the necessary flow for forming the insulating resin in the inner layer circuit is sufficient, and unfilled portions are hardly generated. Become.
These inorganic fillers may be treated with a coupling agent for the purpose of enhancing dispersibility, or may be uniformly dispersed in the resin composition by known kneading such as a kneader, a ball mill, a bead mill, or a three roll.

(Coupling agent)
For the purpose of enhancing the dispersibility of the inorganic filler, a silane coupling agent is preferred as the coupling agent used for the surface treatment of the inorganic filler. For example, N-phenyl-γ-aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-amino Ethyl) aminopropyltriethoxysilane, γ-anilinopropyltrimethoxysilane, γ-anilinopropyltriethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane and N-β -Aminosilane compounds such as (N-vinylbenzylaminoethyl) -γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane and β- (3,4-epoxy) (Cyclohexyl) ethyltrimethoxy As other epoxy silane compounds such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylvinylethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ- Examples include ureidopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane.

[solvent]
The resin composition of the present invention can be used after diluted in a solvent. Examples of the solvent include methyl ethyl ketone, xylene, toluene, acetone, ethylene glycol monoethyl ether, cyclohexanone, ethyl ethoxypropionate, N, N-dimethylformamide, N, N-dimethylacetamide, propylene glycol monomethyl ether and the like. it can. These may be used individually by 1 type, and 2 or more types may be mixed and used for them. The ratio of the solvent used with respect to the resin composition may be a conventionally used ratio, and the amount used can be adjusted in accordance with the facility for forming the coating film of the target insulating resin.

[Preparation of resin composition]
There is no restriction | limiting in particular in the preparation method of the resin composition of this invention, A conventionally well-known preparation method can be used.
For example, the above-mentioned epoxy resin of component (A), UV-active ester group-containing compound of component (B), isocyanate silane of component (C) and epoxy resin curing accelerator of component (D) are added to the solvent. In addition, after adding inorganic filler and various additive components used as necessary, ultrasonic dispersion method, high-pressure collision dispersion method, high-speed rotation dispersion method, bead mill method, high-speed shear dispersion method, rotation and revolution dispersion method, etc. It can be prepared as a varnish by mixing and stirring using various mixers.
The solid content concentration excluding the solvent in the varnish is preferably 40 to 70% by mass from the viewpoint of coating property and the like.

[Wiring board]
The wiring board of the present invention is a cured resin layer (insulating) obtained by forming an uncured resin layer on a substrate having a circuit of a wiring conductor with the above-described resin composition, thermally curing it, and then irradiating with ultraviolet rays. A wiring is formed on the (resin layer) by plating.
(Preparation of carrier film with insulating resin layer)
In the wiring board of the present invention, in order to form an insulating resin layer on a substrate having a circuit of a wiring conductor, first, the resin composition (varnish) of the present invention is applied to a carrier film, and then about 80 to 180 ° C. The carrier film with an insulating resin layer is produced by drying for about 5 to 10 minutes at a temperature of 5 ° C. When the temperature of the drying treatment is 80 ° C. or more and the time is 5 minutes or more, it is preferable because drying proceeds sufficiently and generation of voids in the insulating resin layer can be suppressed. On the other hand, when the temperature of the drying treatment is 180 ° C. or lower and the time is 10 minutes or shorter, it is preferable because drying progresses excessively and the resin flow amount can be suppressed from decreasing. Here, the solvent in the varnish is volatilized by drying, and is a so-called uncured insulating resin layer in an uncured state where no curing treatment is performed.
The thickness of the insulating resin layer (thickness after drying) is preferably at least the minimum film thickness that can ensure the minimum insulation distance from the viewpoint of insulation, and this minimum insulation distance varies depending on the composition of the insulating resin. However, in general, the thickness is preferably 5 μm or more. Although increasing the thickness of the insulating resin layer is advantageous in terms of insulation, it is usually preferably about 40 μm or less from the viewpoint of economy.
Although there is no restriction | limiting in particular as thickness of the said carrier film, About 10-200 micrometers is preferable and 20-100 micrometers is more preferable. Further, as the carrier film, a polyethylene terephthalate (PET) film is often used, and a PET film whose surface is treated with a release agent may be used.

(Board with wiring circuit)
The substrate having the circuit of the wiring conductor used for the wiring board of the present invention (hereinafter sometimes referred to as an insulating substrate with circuit) is not particularly limited as long as it is an insulating substrate having a circuit on at least one surface. Instead, the circuit may be formed on both sides of the insulating substrate, such as a circuit formed only on one side or a double-sided copper-clad laminate. As this insulating substrate with circuit, a known laminated board used in a normal wiring board, for example, glass cloth-epoxy resin, paper-phenol resin, paper-epoxy resin, glass cloth / glass paper-epoxy resin, etc. is used. can do. The circuit may be formed by any known method, using a copper-clad laminate in which a copper foil and the insulating substrate are bonded together, using a subtractive method for etching away unnecessary portions of the copper foil, A known method for manufacturing a wiring board such as an additive method for forming a circuit by electroless plating at a necessary location can be used.
Moreover, you may perform the circuit surface treatment for improving adhesiveness to this circuit surface. This treatment method is also not particularly limited. For example, a copper oxide needle crystal is formed on the circuit surface with an alkaline aqueous solution of sodium hypochlorite, and the formed copper oxide needle crystal is converted into a dimethylamine borane aqueous solution. It is possible to employ a known method such as dipping in a reducing solution.

(Formation of an insulating resin layer on the circuit of an insulating substrate with circuit)
Next, as a method of forming the insulating resin layer on the circuit of the above-described insulating substrate with circuit, the insulating resin layer can be formed by a laminate method or a press method using the carrier film with an insulating resin layer described above.
In the laminating method, a cast film with an insulating resin layer is brought into contact with a circuit of an insulating substrate with a circuit so that the insulating resin layer faces, and the insulating resin layer is laminated using, for example, a vacuum pressure laminator laminator. Thereafter, the carrier film is peeled off.
When using a vacuum pressurizing laminator laminator, the temperature is preferably about 50 to 170 ° C. and the pressure is 0.2 MPa or more. The preferred pressure value also varies depending on the thickness of the substrate, the remaining copper ratio, etc., as with the heating temperature. However, if the pressure is too high, the substrate may be deformed, so it is preferably 1.0 MPa or less. Further, when the degree of vacuum is 15 hPa or less, the embedding property to the inner layer circuit board is good. If the degree of vacuum is low, it is preferable to be low. However, in consideration of the influence of the capability of the apparatus, the waiting time until reaching a predetermined value, and the like on the productivity, it is preferable to carry out in the range of 5 to 10 hPa. The thermocompression bonding time is preferably about 10 to 90 seconds. If it is 10 seconds or more, the time required for the resin to flow to the inner layer circuit is sufficient, and if it is 90 seconds or less, the productivity is good. A more preferable thermocompression bonding time is 20 to 60 seconds.

  On the other hand, in the case of the press method, as described above, the cast film with the insulating resin layer is brought into contact with the circuit of the insulating substrate with circuit so that the insulating resin layer faces, and appropriate conditions are matched to the insulating resin layer to be used. For example, at a rate of temperature increase of about 3 ° C./min, the temperature is increased from 35 ° C. to about 190 ° C. for about 50 minutes, and the pressure is about 2.0 to 3.0 MPa at that temperature. The insulating resin layer can be formed on the circuit of the insulating substrate with circuit by using a method of cooling for about 30 minutes to room temperature after holding for about 60 to 90 minutes.

(Thermosetting treatment of insulating resin layer)
In the wiring board of the present invention, the insulating resin layer formed on the circuit of the insulating substrate with circuit as described above is first heat-cured.
This thermosetting treatment is desirably performed at a temperature and time taking into account subsequent plating treatment or annealing treatment of the wiring conductor. If the curing is advanced too much, the adhesion to the wiring conductor may be reduced during the subsequent plating process. On the contrary, if the curing is insufficient, it may be eroded by the alkaline treatment liquid during the plating process and dissolved in the plating solution. Because there is. In consideration of these matters, it is preferable to cure by applying a heat treatment at 150 to 190 ° C. for about 30 to 90 minutes, for example.

(UV irradiation treatment)
In the wiring board of the present invention, the insulating resin layer that has been heat-cured as described above is subjected to ultraviolet irradiation treatment. The purpose of the ultraviolet irradiation treatment is as described in the above-described resin composition of the present invention.
With respect to the conditions of the ultraviolet irradiation treatment, ultraviolet rays are irradiated so that the amount of light is in the range of 1000 to 5000 mJ / cm ² under an atmospheric pressure atmosphere using an ultraviolet lamp having a maximum wavelength in the range of 300 to 450 nm. It is preferable. A method of irradiating the insulating resin layer with ultraviolet rays under an atmospheric pressure atmosphere is not particularly limited because it differs depending on the ultraviolet device, but a conveyor type ultraviolet irradiation method is preferable in consideration of productivity. As the ultraviolet lamp, a lamp having a maximum wavelength in the range of 300 to 450 nm may be a mercury short arc lamp, a high pressure mercury lamp, a capillary type ultra high pressure lamp, a high pressure lamp, a metal halide lamp, or the like. Among these lamps, metal halide lamps having a wide ultraviolet wavelength over the entire region are preferable.

The purpose of using an ultraviolet lamp having a maximum ultraviolet wavelength in the range of 300 to 450 nm relates to versatility and the wavelength range of ultraviolet rays. That is, an ultraviolet lamp having a maximum wavelength of 300 to 450 nm is generally used as a conveyor type ultraviolet irradiation device, for example, a solder resist post-exposure device. Furthermore, the metal halide conveyor irradiation device has a wide ultraviolet wavelength region, and the effects of the present invention can be exhibited by substituting these devices without requiring a special device. Quantity of ultraviolet light is, adhesive force between the even plating conductor without processing the insulating resin layer between at 1000 mJ / cm ² or more oxidizing roughening solution becomes sufficient, whereas, the adhesive When it is 5000 mJ / cm ² or less The force is well expressed and economically advantageous. A more preferable light amount is in the range of 3000 to 4000 mJ / cm ² .
In this way, by performing the ultraviolet irradiation treatment on the insulating resin layer after the thermosetting treatment, a high adhesive force can be exerted on the wiring conductor even when the uneven shape on the surface of the insulating resin layer is small.

(Treatment with oxidizing roughening solution)
When it is necessary to remove the smear on the bottom of the via hole, it can be removed using an oxidizing roughening solution. As this oxidizing roughening liquid, a chromium / sulfuric acid roughening liquid, an alkaline permanganic acid roughening liquid, a sodium fluoride / chromium / sulfuric acid roughening liquid, a borofluoric acid roughening liquid, or the like can be used. Moreover, when processing with this oxidizing roughening liquid, after immersing in a solvent or alkali liquid, or a mixture liquid (generally swelling liquid or pre-dip liquid), you may process with an oxidizing roughening liquid. . As the solvent, alcohol solvents such as diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, isopropyl alcohol and the like can be used. Further, the alkaline solution is not particularly limited as long as it is a solution that exhibits alkalinity when dissolved in water, and a sodium hydroxide solution, a potassium hydroxide solution, or the like can be used. Furthermore, you may mix a solvent or an alkali liquid, for example, the thing of the composition of sodium hydroxide 3g / L and diethylene glycol monobutyl ether 300mL / L can be used.

(Plating treatment)
In the wiring board of the present invention, the surface of the insulating resin layer treated as described above is subjected to a plating treatment as shown below, for example.
First, the insulating resin layer is immersed in an aqueous hydrochloric acid solution of stannous chloride, neutralized, and further subjected to a plating catalyst application treatment for depositing palladium. The plating catalyst application treatment is performed by immersing in a palladium chloride plating catalyst solution. Next, an electroless plating layer having a thickness of about 0.3 to 1.5 μm is deposited on the plating catalyst by being immersed in an electroless plating solution. If necessary, further electroplating can be performed. As the electroless plating solution used for the electroless plating treatment, a known electroless plating solution can be used, and there is no particular limitation. Further, the electroplating treatment can be performed by a known method and is not particularly limited.
These methods can be repeated to produce a multilayer wiring board.

[Method of manufacturing a wiring board]
The present invention also provides a method for manufacturing a wiring board.
The method for producing a wiring board of the present invention comprises (a) a step of forming an uncured resin layer on a substrate having a circuit of a wiring conductor using the resin composition of the present invention, and (b) the uncured resin layer. It includes a step of heat-curing treatment and then forming a cured resin layer by ultraviolet irradiation treatment, and a step (c) performing an electroless plating treatment on the cured resin layer.
In the method for manufacturing a wiring board according to the present invention, the method may further include (d) a step of performing electroplating on the electroless plating, and between the steps (b) and (c). (C ′) A step of roughening the surface of the cured resin layer with an oxidizing roughening solution may be included.
Each of the above steps is as shown in the description of the wiring board of the present invention described above.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
(Evaluation method)
Each Example and Comparative Example were evaluated by the following methods.
(1) Adhesive strength with outer layer circuit (90 degree peeling, unit: kN / m)
A part of the outer circuit layer (third circuit layer) is formed with a portion of width 10mm and length 100mm, one end is peeled off and gripped with a gripper, and the load when stripped about 50mm vertically at room temperature Was measured.
(2) Roughness of insulating resin layer on the plated copper etching removal surface (surface average roughness, unit: μm)
A test piece from which copper is removed by etching the outer layer circuit is produced. This test piece was cut into about 2 mm square, and using a ultra deep shape measurement microscope “VK-8500 type” manufactured by Keyence Corporation, the measurement length was 149 μm and the magnification was 2000 times at three different points in the test piece. The measurement was performed under the condition of a resolution of 0.05 μm, and a value obtained by subtracting the minimum portion from the maximum portion of the roughness in the measurement length of 149 μm was defined as the surface roughness of the insulating resin layer, and the average value of the three locations was calculated.
(3) Solder heat resistance The multilayer wiring board was cut into 25 mm squares, and immediately after that, it floated in a solder bath adjusted to 288 ° C. ± 2 ° C., and the time until blistering was examined.
(4) Adhesive strength with outer layer circuit after holding at high temperature (90 degree peeling, unit: kN / m)
After holding at 180 ° C. for 100 hours in an explosion-proof dryer, a portion having a width of 10 mm and a length of 100 mm is formed on a part of the outer layer circuit layer (third circuit layer), this one end is peeled off and grasped with a grasping tool. In particular, the load when peeling about 50 mm in the vertical direction was measured.

Example 1
(1) Fabrication of circuit board Glass cloth base epoxy resin double-sided copper-clad laminate [copper foil thickness 18 μm, substrate thickness 0.8 mm, Hitachi Chemical Co., Ltd. E-67 "(trade name)] was etched to produce a circuit board having a circuit layer (hereinafter referred to as a first circuit layer) on one side.
(2) Preparation of Resin Composition (A) Component, tetraphenyl type epoxy resin, “JER-1031” (manufactured by JER Corporation, trade name, epoxy equivalent: 200, described as A1 in Table 1) 24 mass Part, (B) component, UV-active ester group-containing resin, “EXB-9470” (DIC Corporation, trade name, ester equivalent: 223) 13.38 parts by mass, (C) component, 3- Isocyanatopropyltriethoxysilane ("KBE-9007" manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass, and (D) component, 1-cyanoethyl-2-phenylimidazolium trimellitate (manufactured by Shikoku Kasei Kogyo Co., Ltd., 0.072 parts by mass of a trade name “2PZ-CNS”) is dissolved in 40 parts by mass of methyl ethyl ketone (hereinafter referred to as “MEK”) as a solvent, and the present invention. A resin composition (varnish) was obtained.

(3) Formation of insulating resin layer and thermosetting / ultraviolet irradiation treatment The resin composition (varnish) obtained in (2) above is applied onto a polyethylene terephthalate (PET) film (thickness 38 μm) as a carrier film. And a carrier film roll with an insulating resin layer having a film thickness of 50 ± 3 μm was produced by drying at 100 ° C. for 10 minutes.
Furthermore, the above-mentioned carrier film with an insulating resin layer is placed on one side of the circuit board obtained in the above (1) on the side where the insulating resin layer is in contact with the circuit layer, and the batch type vacuum pressure laminator “MVLP-500” (name (Trade name, manufactured by Kikai Co., Ltd.).
Next, after peeling off the carrier film, the insulating resin layer is heat-cured under a curing condition of 170 ° C. for 60 minutes, and then applied to a metal halide lamp (maximum wavelength 350 to 380 nm) using a conveyor type ultraviolet irradiation device. Then, ultraviolet rays were irradiated so that the amount of light was 3000 mJ / cm ² .

(4) Electroless plating treatment and electrolytic plating treatment As a pretreatment for electroless plating, the conditioner liquid “CLC-601” (manufactured by Hitachi Chemical Co., Ltd., trade name) is provided with the insulating resin layer obtained in (3) above. The substrate was immersed at 60 ° C. for 5 minutes, then washed with water, and immersed in a pre-dip solution “PD-201” (trade name, manufactured by Hitachi Chemical Co., Ltd.) for 2 minutes at room temperature. Next is an electroless plating catalyst containing PdCl ₂ "HS-202B" (manufactured by Hitachi Chemical Co., Ltd., trade name), the glass substrate was immersed for 10 minutes at room temperature, washed with water, is an electroless copper plating solution It was immersed in a “CUST-201 plating solution” (trade name, manufactured by Hitachi Chemical Co., Ltd.) for 15 minutes at room temperature, and further subjected to copper sulfate electrolytic plating. Thereafter, annealing treatment was performed at 170 ° C. for 30 minutes to form a conductor layer having a thickness of 20 μm on the surface of the insulating resin layer.

(5) Circuit formation To remove unnecessary portions of the plated conductor layer by etching, the oxide film on the copper surface is removed by buffing # 600, and then an etching resist film is formed and etched, and then for etching. The resist film was removed, and a second circuit including a via hole connected to the first circuit was formed. Furthermore, after the second circuit conductor surface was immersed in an aqueous solution of sodium chlorite: 50 g / L, NaOH: 20 g / L, and trisodium phosphate: 10 g / L at 85 ° C. for 20 minutes for multilayering. This was washed with water and dried at 80 ° C. for 20 minutes to form copper oxide irregularities on the surface of the second circuit conductor.
(6) Production of multilayer wiring board The steps (3) to (5) were repeated to produce a three-layer multilayer wiring board. The outermost circuit layer is referred to as a third circuit layer (or outer circuit layer).
The results of evaluating the multilayer wiring board by the above method are shown in Table 1.

Example 2
In Example 1, as component (A), an epoxy resin (described as A2 in Table 1) having skeleton of hexanediol prepared by the following method was used, and the blending amount was changed as shown in Table 1. Except for the above, various multilayer wiring boards were produced in the same manner as in Example 1. The results evaluated in the same manner as in Example 1 are shown in Table 1.
(Preparation of epoxy resin having hexanediol as skeleton)
A flask equipped with a thermometer and a stirrer was charged with 228 g (1.00 mol) of bisphenol A and 92 g (0.85 mol) of 1,6-hexanediol divinyl ether and heated to 120 ° C. for 1 hour. Further, the mixture was reacted at 120 ° C. for 6 hours to obtain 400 g of a transparent semi-solid modified polyphenol.
Next, 400 g of the modified polyphenols, 925 g (10 mol) of epichlorohydrin, and 185 g of n-butanol were charged and dissolved in a flask equipped with a thermometer, a dropping funnel, a condenser, and a stirrer. Thereafter, the temperature was raised to 65 ° C. while purging with nitrogen gas, and then the pressure was reduced to an azeotropic pressure, and 122 g (1.5 mol) of a 49% aqueous sodium hydroxide solution was added dropwise over 5 hours. Stirring was then continued under these conditions for 0.5 hour. During this time, the distillate distilled azeotropically was separated with a Dean-Stark trap, the aqueous layer was removed, and the reaction was conducted while returning the organic layer to the reaction system. Thereafter, unreacted epichlorohydrin was distilled off under reduced pressure. To the resulting crude epoxy resin, 1000 g of methyl isobutyl ketone and 100 g of n-butanol were added and dissolved. Further, 20 g of a 10% sodium hydroxide aqueous solution was added to this solution and reacted at 80 ° C. for 2 hours. Then, washing with 300 g of water was repeated three times until the pH of the washing solution became neutral. Next, the system was dehydrated by azeotropic distillation, and after passing through microfiltration, the solvent was distilled off under reduced pressure to obtain 457 g of a transparent liquid epoxy resin. The epoxy equivalent was 403.

Examples 3-5 and 7
In Example 1, except that the composition of the resin composition was changed as shown in Table 1, the same operation as in Example 1 was performed to prepare various multilayer wiring boards. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Example 6
Using the same resin composition as in Example 4, the insulating resin layer was formed and thermally cured in the same manner as described in Example 1. Next, a via hole for the insulating resin layer with the substrate in the interlayer connection by Hitachi Via Mechanics, Ltd. CO ₂ laser processing machine "LCO-1B21 Model", beam diameter 80 [mu] m, frequency 500 Hz, pulse width 5 .mu.sec, shot number 7 conditions It was manufactured by processing. Thereafter, the substrate with the insulating resin layer was irradiated with ultraviolet rays so that the amount of light became 3000 mJ / cm ² using a conveyor type ultraviolet irradiation device (maximum wavelength 350 to 380 nm) in which the lamp was a metal halide lamp.
Next, in order to chemically roughen the insulating resin layer, an aqueous solution of diethylene glycol monobutyl ether: 200 mL / L, NaOH: 5 g / L was heated to 80 ° C. as a swelling liquid, and immersed in this for 5 minutes. Next, as a roughening solution, an aqueous solution of KMnO ₄ : 60 g / L, NaOH: 40 g / L was heated to 80 ° C. and immersed for 10 minutes. Subsequently, the mixture was neutralized by immersing in an aqueous solution of a neutralizing solution (SnCl ₂ : 30 g / L, H ₂ SO _{4 having} a concentration of 98% by mass: 300 mL / L) at room temperature for 5 minutes. Thereafter, the same operation as in Example 4 was performed to produce a multilayer wiring board. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Example 8
In Example 2, as shown in Table 1, a resin composition to which spherical silica having an average particle size of 0.5 μm and “SO-25R” (manufactured by Admatechs Co., Ltd., trade name) was added as an inorganic filler. Except for the above, the same operation as in Example 2 was performed to produce a multilayer wiring board. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Example 9
A multilayer wiring board was produced in the same manner as in Example 1 except that the ultraviolet irradiation lamp was changed to a high pressure mercury lamp conveyor type ultraviolet irradiation device (maximum wavelength 310 to 370 nm). The ultraviolet irradiation was performed so that the light amount was 3000 mJ / cm ² as in Example 1.

Comparative Example 1
In Example 1, as shown in Table 1, the composition of the resin composition was the same as in Example 1 except that the ultraviolet-active ester group-containing compound was not used, and a multilayer wiring board was produced. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Comparative Example 2
In the resin composition of Example 1, as shown in Table 1, instead of the UV-active ester group-containing compound, a cresol novolac-type phenol resin (“KA-1165”, trade name, manufactured by DIC Corporation, hydroxyl equivalent: Except for using 119), the same operation as in Example 1 was performed to produce a multilayer wiring board. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Comparative Example 3
As shown in Table 1, in the resin composition of Example 2, the same operation as in Example 2 was performed except that the component (C) was not used, and a multilayer wiring board was produced. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Comparative Example 4
In the resin composition of Example 2, as shown in Table 1, in place of 3-isocyanatopropyltriethoxysilane (C1 component), 2 parts by mass of aminopropyltrimethoxysilane (C2 component) was used. The same operation as in Example 2 was performed to produce a multilayer wiring board. The results evaluated in the same manner as in Example 1 are shown in Table 1.

A1: Tetraphenyl type epoxy resin, “JER-1031” (manufactured by JER Corporation, trade name, epoxy equivalent: 200)
A2: Epoxy resin having hexanediol in the skeleton (epoxy equivalent: 403)
A3: Naphthalene type epoxy resin, “HP-4700” (manufactured by DIC Corporation, trade name, epoxy equivalent: 168)
A4: phenol novolac type epoxy resin, “N-770” (manufactured by DIC Corporation, trade name, epoxy equivalent: 190)
B1: UV-active ester group-containing compound, “EXB-9470” (DIC Corporation, trade name, ester equivalent: 223)
C1: 3-isocyanatopropyltriethoxysilane, “KBE-9007” (trade name, manufactured by Shin-Etsu Silicone)
C2: Aminopropyltrimethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.)
D1: Curing accelerator, imidazole derivative compound, 1-cyanoethyl-2-phenylimidazolium trimellitate (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name “2PZ-CNS”)
E1: Methyl ethyl ketone F1: Inorganic filler, spherical silica with an average particle size of 0.5 μm, “SO-25R” (trade name, manufactured by Admatechs Co., Ltd.)
G1: Cresol novolac type phenol resin, “KA-1165” (trade name, hydroxyl equivalent: 119 manufactured by DIC Corporation)

  From Table 1, the wiring board having the insulating resin layer obtained by thermally curing the resin composition of the present invention and irradiating the resin composition with ultraviolet rays has a small surface roughness of the insulating resin layer as shown in the examples. It can be seen that the adhesive strength with the outer layer copper is good and is suitable for fine wiring. Moreover, it is understood that the solder heat resistance at 288 ° C. is also excellent, and the lead-free solder mounting is also excellent.

According to the present invention, in order to remove smear at the bottom of the via hole, in addition to being able to express a high adhesive force to the wiring conductor even in a state where the uneven shape on the surface of the insulating resin layer is small, a sodium permanganate type or the like Even if it processes with a roughening liquid, the roughening uneven | corrugated shape on the surface of an insulating resin layer is small, and high adhesive force can be ensured with respect to a wiring conductor.
The wiring board produced using the resin composition of the present invention has good adhesive strength with a circuit and is excellent in solder heat resistance.

Claims (10)

  (A) A resin composition comprising an epoxy resin having two or more epoxy groups in one molecule, (B) an ultraviolet active ester group-containing compound, (C) an isocyanate silane, and (D) an epoxy resin curing accelerator.   The resin composition according to claim 1, wherein an ester equivalent of the (B) ultraviolet-active ester group-containing compound is 0.95 to 1.25 equivalents relative to 1 equivalent of epoxy of the (A) epoxy resin.   The resin composition according to claim 1 or 2, wherein the (B) ultraviolet-active ester group-containing compound is a resin having one or more ester groups in one molecule.   A cured resin product obtained by thermally curing the resin composition according to claim 1 and irradiating with ultraviolet rays.   A wiring board obtained by arranging a cured resin layer made of the cured resin according to claim 4 on a substrate having a circuit of a wiring conductor, and forming wiring on the cured resin layer by plating. 6. The wiring board according to claim 5, wherein the ultraviolet ray irradiation is performed using an ultraviolet lamp that radiates in an atmospheric pressure atmosphere in a range of a maximum wavelength of 300 to 450 nm so that the light amount is 1000 to 5000 mJ / cm ² .   (A) a step of forming an uncured resin layer on the substrate having a circuit of a wiring conductor using the resin composition according to any one of claims 1 to 3, and (b) the uncured resin layer. A method of manufacturing a wiring board, comprising: a step of heat-curing treatment, followed by ultraviolet irradiation treatment to form a cured resin layer; and (c) applying an electroless plating treatment to the cured resin layer.   Furthermore, the manufacturing method of the wiring board of Claim 7 including the process of performing an electroplating process on (d) electroless plating.   The production of a wiring board according to claim 7 or 8, further comprising a step of roughening the surface of the cured resin layer with an oxidizing roughening solution between the step (b) and the step (c). Method. 10. The ultraviolet irradiation is performed so that the amount of light is 1000 to 5000 mJ / cm ² using an ultraviolet lamp that emits in a range of a maximum wavelength of 300 to 450 nm in an atmospheric pressure atmosphere in the ultraviolet irradiation process. The manufacturing method of the wiring board in any one.