JP2013023666A - Epoxy resin material, cured product, and plasma-roughened cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin material that can enhance wettability of a rough surface subjected to plasma roughening treatment of a plasma-roughened cured product.SOLUTION: In the epoxy resin material, a resin composition or a B-stage film obtained by molding the resin composition into a film state. The resin composition contains an epoxy resin, a curing agent and inorganic filler. When the surface of a cured product obtained by curing the epoxy resin material is subjected to plasma roughening treatment to obtain a first plasma-roughened cured product having a first rough surface having arithmetic average roughness Ra of 30 nm, the surface free energy of the first rough surface is 50 mJ/mor more. When the surface of the cured product is subjected to plasma roughening treatment to obtain a second plasma-roughened cured product having a second rough surface having arithmetic average roughness Ra of 300 nm, the surface free energy of the second rough surface is 75 mJ/mor less.

Description

  The present invention relates to an epoxy resin material that is, for example, a resin composition or a B-stage film in which the resin composition is formed into a film, and more specifically, the resin composition includes an epoxy resin, a curing agent, and an inorganic filler. And a cured product using the epoxy resin material and a plasma roughened cured product.

  In recent years, notebook personal computers, mobile phones, personal digital assistants, video or music playback devices, electronic devices for game machines, and the like have become widespread, and the electronic devices are becoming smaller and higher performance. Along with this, miniaturization of wiring of circuit boards used in the electronic devices is progressing. In addition, the insulating layer provided on the circuit board is required to have excellent insulating properties, heat resistance, electrical characteristics, dimensional stability, and the like.

  Moreover, in order to satisfy | fill the above-mentioned required quality, the resin composition containing a thermosetting resin is widely used.

  As an example of the resin composition containing the thermosetting resin, Patent Document 1 below discloses a resin composition containing a cyanate ester resin, an anthracene epoxy resin, and a thermoplastic resin such as a phenoxy resin. Yes. Here, it is described that the thermal expansion coefficient of the resin composition is low and that an insulating layer in which smear can be easily removed can be formed.

  In addition, as electronic devices are reduced in size and thickness, an underfill material is interposed between the insulating layer and the electronic component to increase the strength after the electronic component is laminated on the insulating layer provided on the circuit board. To obtain a connection structure. For example, Patent Document 2 below discloses a technique for increasing the affinity between a titanium oxide film and an underfill material by forming a titanium oxide film on an insulating layer and providing the titanium oxide film.

JP 2003-096296 A WO2009 / 048097A1

  When the said insulating layer is formed using the conventional resin composition as described in patent document 1, the wettability of the surface of an insulating layer may be low. For this reason, the underfill material is not sufficiently filled, and voids may occur. In particular, when a fine wiring is provided on the circuit board or a fine wiring is provided on the lower surface of the electronic component laminated on the insulating layer, the gap between the insulating layer and the electronic component is In addition, there is a problem that voids are easily generated in the gaps between the fine wirings.

  On the other hand, in Patent Document 2, in order to provide a titanium oxide film on an insulating layer, extra steps such as a titanium oxide film formation step and an exposure step must be performed. Therefore, there is a problem that the manufacturing efficiency of the connection structure filled with the underfill material is low and the cost is high.

  An object of the present invention is to provide an epoxy resin material capable of enhancing the wettability of the roughened plasma-roughened surface of the plasma-roughened cured product, and a cured product and a plasma-roughened cured product using the epoxy resin material. Is to provide.

According to a broad aspect of the present invention, there is provided an epoxy resin material that is a resin composition containing an epoxy resin or a B-stage film in which the resin composition is formed into a film, and the resin composition comprises an epoxy resin, A curing agent and an inorganic filler are included, and the epoxy resin material is cured at 190 ° C. for 60 minutes to obtain a cured product, and then the surface of the cured product is subjected to plasma roughening treatment so that the arithmetic average roughness Ra is 30 nm. When the first plasma roughened cured product having a certain first rough surface was obtained, the surface free energy of the first rough surface was 50 mJ / m ² or more, and the epoxy resin material was heated at 190 ° C. at 60 ° C. Curing is performed for a minute to obtain a cured product, and then the surface of the cured product is subjected to plasma roughening treatment to obtain a second plasma roughened cured product having a second rough surface having an arithmetic average roughness Ra of 300 nm. When obtained, the second coarse An epoxy resin material having a surface free energy of 75 mJ / m ² or less is provided.

  On the specific situation with the epoxy resin material which concerns on this invention, the average particle diameter of the said inorganic filler is 1.0 micrometer or less.

  In another specific aspect of the epoxy resin material according to the present invention, the content of the inorganic filler is 40% by weight or more and 85% by weight or less in 100% by weight of the total solid content in the resin composition.

  In still another specific aspect of the epoxy resin material according to the present invention, the inorganic filler is silica.

  In another specific aspect of the epoxy resin material according to the present invention, the silica is surface-treated with a coupling agent.

  In still another specific aspect of the epoxy resin material according to the present invention, the resin composition is a B-stage film formed into a film.

  The cured product according to the present invention is obtained by curing the above-described epoxy resin material. The cured product according to the present invention is preferably a substrate or a solder resist.

The plasma roughening cured product according to the present invention is obtained by subjecting a cured product obtained by curing the above-described epoxy resin material to a plasma roughening treatment so as to have a rough surface with an arithmetic average roughness Ra of 30 nm to 300 nm. obtained, the surface free energy of the rough surface 50 mJ / ^{m 2} or more and 75 mJ / ^{m 2} or less. The plasma roughening cured product according to the present invention is preferably a substrate or a solder resist.

In the epoxy resin material according to the present invention, the resin composition includes an epoxy resin, a curing agent, and an inorganic filler, and a first plasma roughened cured product having a first rough surface with an arithmetic average roughness Ra of 30 nm. The second rough surface of the second plasma roughening-cured material having the second rough surface having a surface free energy of 50 mJ / m ² or more and an arithmetic average roughness Ra of 300 nm. Since the surface free energy of the material is 75 mJ / m ² or less, the wettability of the roughened surface of the plasma roughened treatment obtained by the plasma roughening treatment to the underfill material can be improved. .

FIG. 1 is a partially cutaway front sectional view schematically showing a connection structure in which an epoxy resin material according to an embodiment of the present invention is used and an underfill material is filled.

  Details of the present invention will be described below.

(Epoxy resin material)
The epoxy resin material according to the present invention is a resin composition or a B-stage film in which the resin composition is formed into a film.

  The resin composition includes an epoxy resin, a curing agent, and an inorganic filler. In general, a resin composition is required to be capable of forming an insulating layer having excellent insulating properties, heat resistance, electrical characteristics, dimensional stability, and the like. By using an epoxy resin which is a thermosetting resin, required quality required for an insulating layer such as insulation, heat resistance, electrical characteristics and dimensional stability can be enhanced. In particular, the use of an inorganic filler can increase the dimensional stability of the insulating layer.

  In the present specification, the epoxy resin material according to the present invention is cured at 190 ° C. for 60 minutes to obtain a cured product, and then the arithmetic average roughness Ra obtained by plasma-roughening the surface of the cured product is 30 nm. A cured product having a certain first rough surface is referred to as a first plasma roughened cured product.

  Moreover, in this specification, the epoxy resin material according to the present invention is cured at 190 ° C. for 60 minutes to obtain a cured product, and then the arithmetic average roughness Ra obtained by plasma roughening the surface of the cured product is A cured product having a second rough surface of 300 nm is referred to as a second plasma roughened cured product.

In this invention, the surface free energy of the said 1st rough surface in said 1st plasma roughening process hardened | cured material is 50 mJ / m < ² > or more. Furthermore, in this invention, the surface free energy of the said 2nd rough surface in said 2nd plasma roughening process hardened | cured material is 75 mJ / m < ² > or less. By satisfying the relationship between the arithmetic average roughness Ra and the surface free energy, the wettability of the roughened surface of the plasma roughened cured product to the underfill material can be enhanced. Moreover, good wettability with respect to the underfill material can be obtained by any of the first and second plasma roughening treatment cured products in which the plasma roughening treatment conditions are changed. For this reason, when the resin layer is formed using the epoxy resin material according to the present invention, the electronic component is laminated on the resin layer, and the underfill material is filled in the gap between the resin layer and the electronic component. In addition, the filling property of the underfill material can be improved. Furthermore, when the filling property of the underfill material is high, voids are less likely to occur in the space between the insulating layer filled with the underfill material and the electronic component and between the fine wirings. .

  The epoxy resin material according to the present invention is used for forming a resin layer, for laminating an electronic component on the resin layer, and filling an underfill material in a gap between the resin layer and the electronic component. It is preferable that it is the epoxy resin material used for. The resin layer is preferably a cured product obtained by curing an epoxy resin material, and more preferably a plasma roughened cured product obtained by plasma-roughening the cured product. The “plasma roughening process” is a kind of roughening process. The plasma roughening treatment is preferably a plasma desmear treatment. The plasma roughening treatment can be performed under dry conditions without using a roughening solution. The plasma roughening treatment is preferably a plasma dry treatment. In this specification, the term “roughening treatment” means not only general roughening treatment but also desmearing treatment. However, in this specification, the term “desmear treatment” may be used to distinguish from general roughening treatment.

  Hereinafter, details, such as an epoxy resin, a hardening | curing agent, and an inorganic filler contained in the said resin composition, are demonstrated.

[Epoxy resin]
The epoxy resin contained in the resin composition is not particularly limited. A conventionally well-known epoxy resin can be used as this epoxy resin. The epoxy resin refers to an organic compound having at least one epoxy group. As for an epoxy resin, only 1 type may be used and 2 or more types may be used together.

  The resin composition preferably includes a polyfunctional epoxy resin having three or more epoxy groups. More preferably, the resin composition contains two or more types of epoxy resins. It is preferable that at least one of the two or more types of epoxy resins is a polyfunctional epoxy resin having three or more epoxy groups. By using a polyfunctional epoxy resin, the crosslink density of the cured product is further increased, the surface roughness of the plasma roughened cured product is further reduced, and finer wiring is formed on the surface of the cured product. be able to.

  The compounding quantity of the said polyfunctional epoxy resin is not specifically limited. In 100% by weight of the epoxy resin, the content of the polyfunctional epoxy resin is preferably 5% by weight or more, more preferably 10% by weight or more, preferably 80% by weight or less, more preferably 50% by weight or less.

  The polyfunctional epoxy resin includes bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, biphenol type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, phenol aralkyl type. Examples include epoxy resins, naphthol aralkyl epoxy resins, dicyclopentadiene epoxy resins, anthracene epoxy resins, epoxy resins having an adamantane skeleton, epoxy resins having a tricyclodecane skeleton, and epoxy resins having a triazine nucleus as a skeleton. .

  From the viewpoint of further reducing the dimensional change due to heat of the cured product, the polyfunctional epoxy resin is more preferably a naphthalene type epoxy resin, an anthracene type epoxy resin, and an epoxy resin having a triazine nucleus as a skeleton.

  The polyfunctional epoxy resin is more preferably an epoxy resin having a triazine nucleus in the skeleton. By using an epoxy resin having a triazine nucleus in the skeleton, the linear expansion coefficient of the cured product can be considerably lowered. Moreover, the surface free energy can be further increased by using an epoxy resin having a triazine nucleus in the skeleton.

  As an epoxy resin other than the polyfunctional epoxy resin, an epoxy resin containing one or two epoxy groups can be used.

  Other epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenol type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type. Examples thereof include an epoxy resin, a dicyclopentadiene type epoxy resin, an anthracene type epoxy resin, an epoxy resin having an adamantane skeleton, an epoxy resin having a tricyclodecane skeleton, and an epoxy resin having a triazine nucleus in the skeleton.

  The epoxy resin may be liquid at normal temperature (23 ° C.) or may be solid. The epoxy resin is preferably a liquid epoxy resin that is liquid at room temperature. By using the liquid epoxy resin, the handling property of the B stage film can be enhanced. Further, by using a liquid epoxy resin, the surface roughness of the plasma roughened cured product can be further reduced, and finer wiring can be formed on the surface of the cured product.

  The content of the liquid epoxy resin in 100% by weight of the epoxy resin is preferably 10% by weight or more, more preferably 15% by weight or more, still more preferably 30% by weight or more, and particularly preferably 50% by weight or more. The total amount of the epoxy resin may be a liquid epoxy resin.

  Examples of the liquid epoxy resin include bisphenol F type epoxy resins having an epoxy equivalent of 160 to 190 (such as “jER806” and “jER807” manufactured by Mitsubishi Chemical Corporation).

  From the viewpoint of increasing the adhesive strength between the cured product and the metal layer or further reducing the surface roughness of the plasma roughened cured product, the epoxy equivalent of the epoxy resin is within the range of 90 to 1000. It is preferable that The epoxy equivalent is preferably 100 or more, preferably 800 or less, more preferably 400 or less.

[Curing agent]
The curing agent contained in the resin composition is not particularly limited. As the curing agent, a conventionally known curing agent can be used. As for a hardening | curing agent, only 1 type may be used and 2 or more types may be used together.

  Examples of the curing agent include cyanate ester resins (cyanate ester curing agents), phenol compounds (phenol curing agents), amine compounds, thiol compounds (thiol curing agents), acid anhydrides, active ester compounds, and dicyandiamide. Especially, from a viewpoint of obtaining the hardened | cured material in which the dimensional change by a heat | fever is still smaller, it is preferable that the said hardening | curing agent is cyanate ester resin or a phenol compound. The curing agent is preferably a cyanate ester resin, and is preferably a phenol compound. The curing agent preferably has a functional group capable of reacting with the epoxy group of the epoxy resin.

  By using the phenolic curing agent, the handling property of the B stage film having a high silica content can be improved, and the glass transition temperature of the cured product can be further increased. The said phenol type hardening | curing agent is not specifically limited. A conventionally known phenolic curing agent can be used as the phenolic curing agent. As for the said phenol type hardening | curing agent, only 1 type may be used and 2 or more types may be used together.

  As said phenol type hardening | curing agent, a phenyl type phenol type hardening | curing agent or a naphthol type hardening | curing agent etc. are mentioned.

  Commercially available phenolic curing agents include biphenyl phenolic curing agents (“KAYAHARDGPH-103” manufactured by Nippon Kayaku Co., Ltd. and “MEH7851” manufactured by Meiwa Kasei Co., Ltd.), and naphthol curing agents (“SN485 manufactured by Tohto Kasei Co., Ltd.). And “KAYAHARDNHN” manufactured by Nippon Kayaku Co., Ltd.).

  From the viewpoint of increasing the curability of the epoxy resin material and further reducing the surface roughness of the plasma roughened cured product, the phenolic curing agent preferably has two or more hydroxyl groups.

  Moreover, the use of the phenolic curing agent can increase the strength and heat resistance of the cured product, and can further enhance the adhesion between the cured product and the metal layer. Moreover, the smoothness of the surface of hardened | cured material can be improved by use of the said phenol type hardening | curing agent.

  The weight average molecular weight of the curing agent is preferably 100 or more, more preferably 500 or more, preferably 50,000 or less, more preferably 20,000 or less. A B stage film can be easily obtained as the weight average molecular weight of the said phenol type hardening | curing agent is more than the said minimum, and a B stage film does not become weak easily. When the weight average molecular weight of the phenolic curing agent is not more than the above upper limit, the glass transition temperature of the cured product is further increased, and the heat resistance of the cured product is further enhanced.

  The “weight average molecular weight” indicates a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  From the viewpoint of further reducing the surface roughness of the surface of the plasma roughened cured product and forming finer wiring on the surface of the cured product, the equivalent of the curing agent is preferably 250 or less. It is preferable that the said hardening | curing agent contains the hardening | curing agent whose equivalent is 250 or less. The equivalent of the curing agent is, for example, a cyanate ester group equivalent when the curing agent is a cyanate ester resin, a phenolic hydroxyl group equivalent when the curing agent is a phenol compound, and the curing agent is an acid anhydride. Is the acid anhydride group equivalent.

  The content of the curing agent having an equivalent weight of 250 or less in 100% by weight of the curing agent is preferably 30% by weight or more, more preferably 50% by weight or more. The total amount of the curing agent may be a curing agent having an equivalent weight of 250 or less. When the content of the curing agent having an equivalent weight of 250 or less is at least the above lower limit, the surface roughness of the surface of the plasma roughened cured product can be further reduced, and finer wiring can be formed on the surface of the cured product. Can be formed. Furthermore, the glass transition temperature of hardened | cured material can be made still higher that content of the hardening | curing agent whose equivalent is 250 or less is more than the said minimum.

  The compounding ratio of the epoxy resin and the curing agent is not particularly limited. The compounding ratio of the epoxy resin and the curing agent is appropriately determined depending on the types of the epoxy resin and the curing agent.

[Inorganic filler]
The inorganic filler contained in the resin composition is not particularly limited. A conventionally known inorganic filler can be used as the inorganic filler. As for the said inorganic filler, only 1 type may be used and 2 or more types may be used together.

  Examples of the inorganic filler include silica, talc, clay, mica, hydrotalcite, alumina, magnesium oxide, aluminum hydroxide, aluminum nitride, boron nitride, and titanate. Of these, silica is preferable, and fused silica is more preferable. By using silica, the surface roughness of the surface of the plasma roughened cured product can be effectively reduced. The shape of silica is preferably substantially spherical.

  The average particle diameter of the inorganic filler is preferably in the range of 0.1 to 20 μm. The average particle diameter is more preferably 0.2 μm or more, more preferably 2 μm or less, and still more preferably 1 μm or less. A median diameter (d50) value of 50% is employed as the average particle diameter of the filler. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring apparatus.

  From the viewpoint of further enhancing the filling properties of the underfill material and further reducing the occurrence of voids, the average particle size of the inorganic filler is preferably 1 μm or less.

  The inorganic filler is preferably surface-treated, and more preferably surface-treated with a coupling agent. Thereby, the dispersibility of the inorganic filler in the epoxy resin material and the affinity between the inorganic filler and other components are increased. By using the inorganic filler surface-treated with the coupling agent, particularly by using the silica surface-treated with the coupling agent, the arithmetic average roughness Ra of the rough surface can be further reduced.

  Examples of the coupling agent include silane coupling agents, titanate coupling agents, and aluminum coupling agents. The coupling agent used for the surface treatment is epoxy silane, amino silane, vinyl silane, aminophenyl silane, styryl silane, methacryloxy silane, acryloxy silane, mercapto silane, sulfur silane, (meth) acrylic acid silane, isocyanate silane or ureido silane. It is preferable that

  The content of the inorganic filler is preferably 40% by weight or more, more preferably 50% by weight in 100% by weight of the total solid content (hereinafter sometimes abbreviated as total solid content B) contained in the resin composition. % Or more, preferably 85% by weight or less, more preferably 80% by weight or less. When the content of the inorganic filler is not less than the above lower limit, the dimensional change due to heat of the cured product can be further reduced, and the surface free energy of the surface of the plasma roughened cured product can be appropriately increased. . When the content of the inorganic filler is not more than the above upper limit, the surface roughness of the surface of the plasma roughened cured product can be further reduced, and the surface shape can be improved. “Total solid content B” refers to the total of the epoxy resin, the curing agent, the inorganic filler, and the solid content blended as necessary. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

  In the total solid content B of 100% by weight, the total content of the epoxy resin and the curing agent is preferably 60% by weight or less, more preferably 50% by weight or less, preferably 15% by weight or more, more preferably 20%. % By weight or more.

  From the viewpoint of increasing the surface free energy, the coupling agent for surface-treating the inorganic filler is preferably epoxy silane, vinyl silane or aminophenyl silane.

  Regarding the use of the silane coupling agent, vinyl silane or aminophenyl silane is more preferable when the total content of the epoxy resin and the curing agent is 44% by weight or less in the total solid content B of 100% by weight. By using such a silane coupling agent, aggregation of the inorganic filler present in the resin can be suppressed.

[Phenoxy resin]
The resin composition may contain a phenoxy resin. By using the phenoxy resin, the followability of the epoxy resin material to the unevenness of the circuit can be improved, the surface roughness of the surface of the plasma roughening treatment can be further reduced, and the roughness is uniform. Can be.

  The phenoxy resin is not particularly limited. As the phenoxy resin, a conventionally known phenoxy resin can be used. As for the said phenoxy resin, only 1 type may be used and 2 or more types may be used together.

  Examples of the phenoxy resin include phenoxy resins having a skeleton such as a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a biphenyl skeleton, a novolac skeleton, and a naphthalene skeleton. The phenoxy resin preferably has a weight average molecular weight in the range of 5,000 to 100,000. Specific examples of the phenoxy resin include, for example, “YP50”, “YP55” and “YP70” manufactured by Toto Kasei Co., Ltd., and “1256B40”, “4250”, “4256H40”, “4275” manufactured by Mitsubishi Chemical Corporation, “YX6954BH30”, “YX8100BH30”, “YL7600DMAcH25”, “YL7213BH30”, and the like.

  Since the adhesive strength between the cured product and the metal layer can be increased when the surface of the cured product is subjected to a plasma roughening treatment and then plated to form a metal layer, the phenoxy resin has a biphenyl skeleton or a biphenol. It preferably has a skeleton, and more preferably has a biphenol skeleton.

  The content of the phenoxy resin is not particularly limited. The content of the phenoxy resin is in the range of 0 to 40% by weight in 100% by weight of the total solid content excluding the inorganic filler contained in the resin composition (hereinafter sometimes abbreviated as the above-mentioned total solid content A). It is preferable that In the total solid content A of 100% by weight, the content of the phenoxy resin is more preferably 20% by weight or less. The phenoxy resin may not be used. When the content of the phenoxy resin is not more than the above upper limit, the surface roughness of the plasma roughened cured product can be made more uniform. “Total solid content A” refers to the total of the epoxy resin, the curing agent, and other solid contents blended as necessary. The total solid content A does not contain an inorganic filler. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

[Details of other components and epoxy resin materials]
The said resin composition may contain the hardening accelerator as needed. The curing accelerator is not particularly limited, and a conventionally known curing accelerator can be used. As for the said hardening accelerator, only 1 type may be used and 2 or more types may be used together.

  Examples of the curing accelerator include imidazole compounds, phosphorus compounds, amine compounds, and organometallic compounds.

  Examples of the imidazole compound include 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl- 2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-un Decylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2 ′ -Methyl Midazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl- (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-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-dihydroxymethylimidazole Can be mentioned.

  Examples of the phosphorus compound include triphenylphosphine.

  Examples of the organic metal salt include zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), and trisacetylacetonate cobalt (III).

  Examples of the amine compound include secondary amines such as piperidine and dimethylaminopyridine, and tertiary amines such as N, N-dimethylpiperazine triethylenediamine.

  From the viewpoint of enhancing the electrical insulation of the cured product, the curing accelerator is particularly preferably an imidazole compound. From the viewpoint of enhancing the electrical insulation of the cured product, the curing accelerator preferably does not contain an organometallic compound.

  The content of the curing accelerator is not particularly limited. From the viewpoint of efficiently curing the epoxy resin material, the content of the curing accelerator is preferably in the range of 0.01 to 3% by weight in 100% by weight of the total solid content A.

  For the purpose of improving impact resistance, heat resistance, resin compatibility, workability, etc., the resin composition includes coupling agents, colorants, antioxidants, UV degradation inhibitors, antifoaming agents, thickeners. A thixotropic agent and other resins other than those mentioned above may be added.

  Examples of the coupling agent include silane coupling agents, titanate coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include vinyl silane, amino silane, imidazole silane, and epoxy silane.

  The content of the coupling agent is not particularly limited. In the total solid content A of 100% by weight, the content of the coupling agent is preferably in the range of 0.01 to 3% by weight.

  Examples of the other resins include polyphenylene ether resin, polyacetal resin, polybutyral resin, divinyl benzyl ether resin, polyarylate resin, diallyl phthalate resin, polyimide resin, benzoxazine resin, benzoxazole resin, bismaleimide resin, and acrylate resin. Can be mentioned.

  In order to obtain the resin composition, a solvent may be used. The resin composition may contain a solvent. The solvent is not particularly limited, and a solvent exhibiting good solubility for the components contained in the resin composition is appropriately selected and used. Examples of the solvent include acetone, methanol, ethanol, butanol, 2-propanol, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, 2-acetoxy-1-methoxypropane, toluene, xylene, and methyl ethyl ketone. N, N-dimethylformamide, methyl isobutyl ketone, N-methylpyrrolidone, n-hexane, cyclohexane, cyclohexanone, and naphtha as a mixture. As for the said solvent, only 1 type may be used and 2 or more types may be used together.

  The resin composition is preferably used by volatilizing most of the solvent. In order to volatilize the solvent, heat drying may be performed to such an extent that curing by heat does not proceed excessively. By drying the resin composition containing a solvent, for example, at 90 to 200 ° C. for 10 to 180 minutes, a B-stage film having good handling properties can be obtained.

  As a method for forming the resin composition into a film, for example, an extrusion molding method is used in which the resin composition is melt-kneaded using an extruder, extruded, and then formed into a film using a T-die or a circular die. Examples thereof include a casting molding method in which the resin composition is dissolved or dispersed in a solvent such as an organic solvent and then cast into a film, and other conventionally known film molding methods. Of these, the extrusion molding method or the casting molding method is preferable because the thickness can be reduced. The film includes a sheet.

  A B-stage film can be obtained by forming the resin composition into a film.

  A film-like resin composition having good handling properties that can be obtained by the drying process as described above is referred to as a B-stage film. Furthermore, in order to further improve the handleability, a film-like resin composition that is in a semi-cured state within a range that does not lead to complete curing is also referred to as a B-stage film.

  The B-stage film is a semi-cured product in a semi-cured state. The semi-cured product is not completely cured and curing can proceed further.

  The content of the solvent is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, preferably 6 parts by weight or less, more preferably 100 parts by weight of the solid content of the B-stage film. 3 parts by weight or less. When the content of the solvent is not less than the above lower limit and not more than the above upper limit, the adhesiveness of the surface of the B stage film does not become too high, and handling properties can be improved. Furthermore, when the B stage film is laminated on another member, the surface flatness can be improved.

  The said resin composition can be used suitably in order to form a laminated film provided with a base material and the B stage film laminated | stacked on one surface of this base material. A B-stage film of a laminated film is formed from the resin composition.

  Examples of the base material of the laminated film include polyester resin films such as polyethylene terephthalate film and polybutylene terephthalate film, olefin resin films such as polyethylene film and polypropylene film, polyimide resin film, metal foil such as copper foil and aluminum foil, and the like. Can be mentioned. The surface of the base material may be subjected to a release treatment as necessary.

  When the epoxy resin material is used as an insulating layer of a circuit, the thickness of the layer formed of the epoxy resin material is preferably equal to or greater than the thickness of the conductor layer that forms the circuit. The thickness of the layer formed of the epoxy resin material is preferably 5 μm or more, and preferably 200 μm or less.

  The epoxy resin material may be impregnated into a base material to form a prepreg. The prepreg includes a base material and the epoxy resin material impregnated in the base material.

  Examples of the base material include a woven fabric or a non-woven fabric formed of metal, glass, carbon, aramid, polyester, or aromatic polyester, and a porous film formed of a fluorine-based resin or a polyester-based resin. .

(Printed wiring board)
Next, the printed wiring board will be described.

  The printed wiring board can be obtained, for example, by using a film formed of the epoxy resin material according to the present invention and heat-pressing the film.

  A metal foil can be laminated on one side or both sides of the film. The method for laminating the film and the metal foil is not particularly limited, and a known method can be used. For example, the film can be laminated on the metal foil using an apparatus such as a parallel plate press or a roll laminator while applying pressure while heating or without heating. The heating temperature and the pressurizing pressure can be appropriately changed and are not particularly limited. The heating temperature is preferably 60 ° C. or higher, more preferably 80 ° C. or higher, preferably 220 ° C. or lower, more preferably 180 ° C. or lower. The pressure of the pressurization is preferably 0.5 MPa or more, more preferably 1 MPa or more, preferably 10 MPa or less, more preferably 6 MPa or less.

(B stage film and laminated film)
A B-stage film can be obtained by forming the resin composition into a film.

  A film-like resin composition having good handling properties that can be obtained by the drying process as described above is referred to as a B-stage film. Furthermore, in order to further improve the handleability, a film-like resin composition that is in a semi-cured state within a range that does not lead to complete curing is also referred to as a B-stage film.

  The B-stage film is a semi-cured product in a semi-cured state. The semi-cured product is not completely cured and curing can proceed further.

  The content of the solvent is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, preferably 6 parts by weight or less with respect to 100 parts by weight of the non-volatile solid content of the B-stage film. More preferably, it is 3 parts by weight or less. When the content of the solvent is not less than the above lower limit and not more than the above upper limit, the adhesiveness of the surface of the B stage film does not become too high, and handling properties can be improved. Furthermore, when the B stage film is laminated on another member, the surface flatness can be improved.

  The epoxy resin material which concerns on this invention can be used suitably in order to form a laminated film provided with a base material and the B stage film laminated | stacked on one surface of this base material. The B stage film of the laminated film is formed from the epoxy resin material according to the present invention.

  Examples of the base material of the laminated film include polyester resin films such as polyethylene terephthalate film and polybutylene terephthalate film, olefin resin films such as polyethylene film and polypropylene film, polyimide resin film, metal foil such as copper foil and aluminum foil, and the like. Can be mentioned. The surface of the base material may be subjected to a release treatment as necessary.

(Hardened product and plasma roughened cured product)
The cured product according to the present invention is obtained by curing the above-described epoxy resin material. The cured product according to the present invention is preferably a substrate or a solder resist.

The plasma roughened cured product according to the present invention is obtained by subjecting a cured product obtained by curing the above-described epoxy resin material to plasma roughening. The plasma roughened cured product according to the present invention is preferably obtained by performing plasma roughening so that the arithmetic average roughness Ra has a rough surface of 30 nm or more and 300 nm or less, and the surface free energy of the rough surface is obtained. is 50 mJ / ^{m 2} or more, is preferably 75 mJ / ^{m 2} or less. The plasma roughening cured product according to the present invention is preferably a substrate or a solder resist.

  For the plasma roughening treatment, for example, a microwave plasma apparatus M100-ST (manufactured by Nissin Co.) can be used.

(Copper-clad laminate and circuit board)
The epoxy resin material according to the present invention is suitably used for obtaining a copper-clad laminate. An example of the copper-clad laminate is a copper-clad laminate comprising a copper foil and a B stage film laminated on one surface of the copper foil. The copper-clad laminate B-stage film is formed of the epoxy resin material according to the present invention.

  The thickness of the copper foil of the copper-clad laminate is not particularly limited. The thickness of the copper foil is preferably in the range of 1 to 50 μm. Moreover, in order to raise the adhesive strength of the hardened | cured material layer which hardened B stage film, and copper foil, it is preferable that the said copper foil has a fine unevenness | corrugation on the surface. The method for forming the unevenness is not particularly limited. Examples of the method for forming the unevenness include a formation method by treatment using a known chemical solution.

  Moreover, the epoxy resin material according to the present invention is suitably used for obtaining a multilayer substrate. As an example of the multilayer substrate, there is a multilayer substrate including a circuit board and a cured product layer laminated on the surface of the circuit board. The cured product layer is a resin layer. The cured product layer of the multilayer substrate is formed by curing the resin composition or a B-stage film in which the resin composition is formed into a film. It is preferable that the said hardened | cured material layer is laminated | stacked on the surface in which the circuit of the circuit board was provided. Part of the cured product layer is preferably embedded between the circuits. It is preferable that the said hardened | cured material layer is a plasma roughening process hardened | cured material layer by which the plasma roughening process was carried out.

  In the multilayer substrate, it is more preferable that the surface of the cured product layer opposite to the surface on which the circuit substrate is laminated is subjected to plasma roughening treatment.

  The multilayer substrate may further include a copper plating layer laminated on the surface of the cured product layer subjected to the plasma roughening treatment.

  An electronic component such as a semiconductor chip may be stacked on a substrate such as the multilayer substrate. Moreover, an electronic component may be laminated | stacked on the hardened | cured material layer (resin layer) on a board | substrate. Furthermore, an underfill material may be filled between the cured product layer and the electronic component.

  In FIG. 1, the connection structure 1 using the epoxy resin material which concerns on one Embodiment of this invention is shown with a partial notch front sectional drawing.

  In the connection structure 1 shown in FIG. 1, a metal layer 3 (wiring) is provided on a substrate 2. A resin layer 4 is formed between the metal layers 3 on the substrate 2. The resin layer 4 is a cured product layer and is formed by curing an epoxy resin material. On the metal layer 3 and the resin layer 4, an electronic component 5 having an electrode 6 provided on the lower surface is laminated. The metal layer 3 and the electrode 6 are connected. An underfill material 7 is filled in a gap between the resin layer 4 and the electronic component 5.

  By forming the resin layer 4 using the epoxy resin material, the wettability of the resin layer 4 is increased, the underfill material 7 can be efficiently filled on the resin layer 4, and voids are hardly generated. can do. For example, even if the width and height of the gap is 4 μm or less, the underfill material 7 can be efficiently filled into the gap between the resin layer 4 and the electronic component 5, and voids are less likely to occur. be able to.

  Hereinafter, the present invention will be specifically described by giving examples and comparative examples. The present invention is not limited to the following examples.

    In the examples and comparative examples, the following materials were used.

(Epoxy resin)
Liquid bisphenol A epoxy resin ("RE-410S" manufactured by Nippon Kayaku Co., Ltd.)
Epoxy resin having a triazine ring (“TEPIC” manufactured by Nissan Chemical Industries, epoxy equivalent 105)

(Curing agent)
Phenol curing agent (“MEH7851” manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent 241 and weight average molecular weight 8000)
Cyanate curing agent ("PT-60" manufactured by Lonza Japan)
Active ester curing agent (“HPC-8000” manufactured by DIC)

(Curing accelerator)
Imidazole compound (2-phenyl-4-methylimidazole, “2P4MZ” manufactured by Shikoku Chemicals)
Dimethylaminopyridine (DMAP)

(Inorganic filler)
Slurry A containing silica treated with epoxy silane (“Advertex Corporation SC2050-MTF”, fused silica having an average particle size of 0.5 μm, 100 parts by weight of silica is an epoxy silane coupling agent (3-glycidoxypropyltrimethoxysilane, “KBM-403” manufactured by Shin-Etsu Chemical Co., Ltd.) surface-treated with 1.5 parts by weight, including 70% solids and 30% methyl ethyl ketone)

(High molecular weight component)
High molecular weight component (modified biphenol skeleton-containing phenoxy resin solution, manufactured by Mitsubishi Chemical Corporation, trade name “YX6954BH30”, solid content 30% by weight, solvent is a mixed solvent of MEK (methyl ethyl ketone) and cyclohexanone)

(Pigment)
Pigment (“MHI Blue” manufactured by Mikuni Dye Co.)

(solvent)
Methyl ethyl ketone

Example 1
56 parts by weight of slurry A containing epoxy silane-treated silica (“Advertex” SC2050-MTF ”) and 12 parts by weight of liquid bisphenol A type epoxy resin (“ RE-410S ”manufactured by Nippon Kayaku Co., Ltd.) 8 parts by weight of an epoxy resin having a triazine ring (“TEPIC” manufactured by Nissan Chemical Industries), 20 parts by weight of a phenol curing agent (“MEH7851” manufactured by Meiwa Kasei Co., Ltd.), and an imidazole compound (“2P4MZ” manufactured by Shikoku Kasei Co., Ltd.) 0 .3 parts by weight and 3 parts by weight of a high molecular weight component (“YX6954BH30”) as solids were added and stirred at 1000 rpm for 3 hours using a stirrer.

  Thereafter, 0.2 part by weight of a pigment (“MHI Blue” manufactured by Mikuni Dye Co., Ltd.) was added and stirred at 1000 rpm for 1 hour to obtain a resin composition.

  Using a coating machine, the resin composition was coated on the release treated surface of a PET film (“XG284” manufactured by Toray Industries, Inc., thickness 25 μm). It dried for 12 minutes in a 100 degreeC gear oven, and the solvent was volatilized. In this way, a B-stage film having a thickness of 25 μm and a residual solvent amount of 3% by weight was obtained on the PET film.

(Example 2)
A slurry A containing epoxy silane-treated silica (“SC2050-MTF” manufactured by Admatechs) is 65 parts by weight in solid content, and 9 parts by weight of liquid bisphenol A type epoxy resin (“RE-410S” manufactured by Nippon Kayaku Co., Ltd.) 5 parts by weight of an epoxy resin having a triazine ring (“TEPIC” manufactured by Nissan Chemical Industries), 17 parts by weight of a phenol curing agent (“MEH7851” manufactured by Meiwa Kasei Co., Ltd.), and an imidazole compound (“2P4MZ” manufactured by Shikoku Kasei Co., Ltd.) 0 .3 parts by weight and 3 parts by weight of a high molecular weight component (“YX6954BH30”) as solids were added and stirred at 1000 rpm for 3 hours using a stirrer.

  Thereafter, 0.2 part by weight of a pigment (“MHI Blue” manufactured by Mikuni Dye Co., Ltd.) was added and stirred at 1000 rpm for 1 hour to obtain a resin composition.

  Using the obtained resin composition, a B-stage film having a thickness of 25 μm and a residual solvent amount of 3% by weight on a PET film was obtained in the same manner as in Example 1.

(Example 3)
56 parts by weight of slurry A containing epoxy silane-treated silica (“Advertex” SC2050-MTF ”) and 12 parts by weight of liquid bisphenol A type epoxy resin (“ RE-410S ”manufactured by Nippon Kayaku Co., Ltd.) 8 parts by weight of an epoxy resin having a triazine ring (“TEPIC” manufactured by Nissan Chemical Industries), 20 parts by weight of a cyanate curing agent (“PT-60” manufactured by Lonza Japan), and an imidazole compound (“2P4MZ” manufactured by Shikoku Kasei Co., Ltd.) ) 0.3 parts by weight and 3 parts by weight of a high molecular weight component (“YX6954BH30”) as solids were added and stirred at 1000 rpm for 3 hours using a stirrer.

  Thereafter, 0.2 part by weight of a pigment (“MHI Blue” manufactured by Mikuni Dye Co., Ltd.) was added and stirred at 1000 rpm for 1 hour to obtain a resin composition.

  Using the obtained resin composition, a B-stage film having a thickness of 25 μm and a residual solvent amount of 3% by weight on a PET film was obtained in the same manner as in Example 1.

Example 4
56 parts by weight of slurry A containing epoxy silane-treated silica (“Advertex” SC2050-MTF ”) and 12 parts by weight of liquid bisphenol A type epoxy resin (“ RE-410S ”manufactured by Nippon Kayaku Co., Ltd.) , 8 parts by weight of an epoxy resin having a triazine ring (“TEPIC” manufactured by Nissan Chemical Industries), 20 parts by weight of an active ester curing agent (“HPC-8000” manufactured by DIC), 0.2% of dimethylaminopyridine (hereinafter referred to as DMAP) Part by weight and 3 parts by weight of a high molecular weight component (“YX6954BH30”) in solid content were added and stirred at 1000 rpm for 3 hours using a stirrer.

  Thereafter, 0.2 part by weight of a pigment (“MHI Blue” manufactured by Mikuni Dye Co., Ltd.) was added and stirred at 1000 rpm for 1 hour to obtain a resin composition.

  Using the obtained resin composition, a B-stage film having a thickness of 25 μm and a residual solvent amount of 3% by weight on a PET film was obtained in the same manner as in Example 1.

(Comparative Example 1)
29 parts by weight of a liquid bisphenol A type epoxy resin (“RE-410S” manufactured by Nippon Kayaku Co., Ltd.), 19 parts by weight of an epoxy resin having a triazine ring (“TEPIC” manufactured by Nissan Chemical Industries), and a phenol curing agent (Maywa Kasei Co., Ltd.) 48 parts by weight of “MEH7851”), 0.5 parts by weight of an imidazole compound (“2P4MZ” manufactured by Shikoku Kasei Co., Ltd.) and 3 parts by weight of a high molecular weight component (“YX6954BH30”) in solid content are added, and 40 parts by weight of methyl ethyl ketone The mixture was stirred at 1000 rpm for 3 hours using a stirrer while diluting at a portion.

  Thereafter, 0.2 part by weight of a pigment (“MHI Blue” manufactured by Mikuni Dye Co., Ltd.) was added and stirred at 1000 rpm for 1 hour to obtain a resin composition.

  Using the obtained resin composition, a B-stage film having a thickness of 25 μm and a residual solvent amount of 3% by weight on a PET film was obtained in the same manner as in Example 1.

(Evaluation)
(1) Arithmetic average roughness Ra and ten-point average roughness Rz
On the obtained B stage film, the polypropylene film which is a protective film was bonded together and rolled up. Then, the protective film bonded to the B stage film on the PET film was peeled off, and the exposed B stage film was temporarily attached to both surfaces of the copper clad laminate. By using a vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd.), a B-stage film was laminated on both sides of the copper-clad laminate under the conditions of a temperature of 100 ° C. and a pressure of 1.0 MPa. Under the conditions, hot pressing with a SUS end plate was performed. Subsequently, the PET film was peeled off, and the B-stage film was thermally cured at 190 ° C. and 60 minutes to obtain a cured resin composition. Thereafter, a via hole is formed in the cured resin composition under the conditions of energy 2 mJ, pulse width 18 μs, and number of shots 2 with a carbon dioxide laser device (“LC-1K21” manufactured by Hitachi Engineering Co., Ltd.). Obtained. The surface of the obtained laminate A was subjected to plasma roughening treatment (desmear treatment) under the following first condition and second condition, and evaluated.

(First condition)
Using a microwave plasma apparatus M110-ST (manufactured by Nissin Co., Ltd.), plasma roughening treatment (desmear treatment) was performed for 15 seconds at an output of 5 kW, a gas species O ₂ / N ₂ = 80/20, and a flow rate of 5 L / min. Then, it wash | cleaned with the pure water and obtained 1st laminated body B1 containing 1st plasma roughening process hardened | cured material b1.

(Second condition)
Using a microwave plasma apparatus M110-ST (manufactured by Nissin Co., Ltd.), plasma roughening treatment (desmear treatment) was performed for 60 seconds at an output of 5 kW, a gas species O ₂ / N ₂ = 80/20, and a flow rate of 5 L / min. Then, it wash | cleaned with the pure water and obtained 2nd laminated body B2 containing 2nd plasma roughening process hardened | cured material b2.

(Measurement)
Arithmetic average roughness Ra of the surfaces (rough surfaces) of the first and second plasma roughening-treated cured products b1 and b2 using a non-contact type surface roughness meter (product name “WYKO” manufactured by Beco). The ten-point average roughness Rz was measured. The arithmetic average roughness Ra and the ten-point average roughness Rz were measured in accordance with JIS B 0601-1994.

(2) Water contact angle The first and second plasma roughening cured products b1 and b2 obtained by the evaluation of (1) above using a contact angle meter (“DM-501” manufactured by Kyowa Interface Science Co., Ltd.) The water contact angle of the surface (rough surface) was measured by the droplet method.

(3) Surface free energy Contact angle meter (by using “DM-501” manufactured by Kyowa Interface Science Co., Ltd.) of the first and second plasma roughened cured products b1 and b2 obtained by the evaluation in (1) above. The water contact angle of the surface (rough surface) and the contact angle of diiodomethane were measured by the droplet method, and the surface free energy was calculated by the Owens-Wendt method.

(4) Desmear property Using an electron microscope “SEM”, the via holes of the first and second laminates B1 and B2 obtained in the evaluation of (1) above were observed, and the amount of smear residue at the bottom of the via hole, via hole The shape of was evaluated.

(5) Average linear expansion coefficient The B stage film was thermally cured at 190 ° C. and 60 minutes to obtain a cured product obtained by curing the B stage film. The obtained cured product was cut into a size of 3 mm × 25 mm. Using a linear expansion coefficient meter (“TMA / SS120C” manufactured by Seiko Instruments Inc.), 25 to 150 of the cured product cut under conditions of a tensile load of 3.3 × 10 ⁻² N and a heating rate of 5 ° C./min. The average coefficient of linear expansion at 0 ° C. was measured. The case where the average linear expansion coefficient was 30 ppm / ° C. or less was judged as “X” when the average linear expansion coefficient exceeded 30 ppm / ° C.

  The results are shown in Table 1 below.

DESCRIPTION OF SYMBOLS 1 ... Connection structure 2 ... Board | substrate 3 ... Metal layer 4 ... Resin layer 5 ... Electronic component 6 ... Electrode 7 ... Underfill material

Claims (10)

An epoxy resin material that is a resin composition containing an epoxy resin or a B-stage film in which the resin composition is formed into a film,
The resin composition includes an epoxy resin, a curing agent, and an inorganic filler,
The epoxy resin material is cured at 190 ° C. for 60 minutes to obtain a cured product, and then the surface of the cured product is plasma-roughened to have a first rough surface having an arithmetic average roughness Ra of 30 nm. When the plasma roughened cured product is obtained, the surface free energy of the first rough surface is 50 mJ / m ² or more,
The epoxy resin material is cured at 190 ° C. for 60 minutes to obtain a cured product, and then the surface of the cured product is subjected to plasma roughening treatment to obtain a second rough surface having a second rough surface with an arithmetic average roughness Ra of 300 nm. An epoxy resin material having a surface free energy of 75 mJ / m ² or less when the plasma roughened cured product is obtained.   The epoxy resin material according to claim 1, wherein the inorganic filler has an average particle size of 1.0 μm or less.   The epoxy resin material according to claim 1 or 2, wherein the content of the inorganic filler is 40% by weight or more and 85% by weight or less in 100% by weight of the total solid content in the resin composition.   The epoxy resin material according to claim 1, wherein the inorganic filler is silica.   The epoxy resin material according to claim 4, wherein the silica is surface-treated with a coupling agent.   The epoxy resin material according to any one of claims 1 to 5, wherein the resin composition is a B-stage film formed into a film shape.   Hardened | cured material obtained by hardening the epoxy resin material of any one of Claims 1-6.   The hardened | cured material of Claim 7 which is a board | substrate or a soldering resist. By subjecting the cured product obtained by curing the epoxy resin material according to any one of claims 1 to 6 to a plasma roughening treatment so as to have a rough surface having an arithmetic average roughness Ra of 30 nm or more and 300 nm or less. Obtained,
The surface free energy of the rough surface 50 mJ / ^{m 2} or more and 75 mJ / ^{m 2} or less, plasma roughening treatment cured product.   The plasma roughening treatment cured product according to claim 9, which is a substrate or a solder resist.

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