WO2014156734A1 - Laminate, method for producing laminate and multilayer substrate - Google Patents

Abstract

Provided is a laminate wherein the bonding strength between a cured product and a metal layer is increased. A laminate (1) according to the present invention is provided with: a cured product (2) that is obtained by curing an epoxy resin material which contains an epoxy resin, a curing agent and an inorganic filler; and a metal layer (3) that is laminated on the surface of the cured product (2). Parts of the metal layer (3) are embedded in the cured product (2) in a plurality of positions, and the maximum depth among all the depths of the plurality of metal layer parts (3a-3d) embedded in the cured product (2) is 0.5 μm or more, while the maximum interval among all the intervals of the plurality of metal layer parts (3a-3d) embedded in the cured product (2) is 0.5 μm or more.

Description

LAMINATE, METHOD FOR PRODUCING LAMINATE, AND MULTILAYER SUBSTRATE

The present invention relates to a laminate comprising a cured product and a metal layer laminated on the surface of the cured product, and a method for producing the laminate. The present invention also relates to a multilayer substrate using the above laminate.

Conventionally, various resin compositions have been used to obtain electronic parts such as laminates and printed wiring boards. For example, in a multilayer printed wiring board, a resin composition is used in order to form an insulating layer for insulating inner layers or to form an insulating layer located in a surface layer portion. In the multilayer printed wiring board, metal wiring is often formed on the surface of the insulating layer.

As an example of the resin composition, the following Patent Document 1 discloses a resin composition containing a cyanate ester resin and a naphthylene ether type epoxy resin. This resin composition may contain an inorganic filler. In Patent Document 1, in the wet roughening step, the roughness of the surface of the insulating layer can be reduced, a plated conductor layer having sufficient peel strength can be formed on the insulating layer, and the dielectric of the insulating layer can be formed. It is described that the resin composition which can make a characteristic and a coefficient of thermal expansion favorable can be provided.

JP 2011-144361 A

In a multilayer printed wiring board, it is strongly demanded that peeling between an insulating layer and a metal wiring laminated on the insulating layer hardly occurs. For this reason, it is desired that the adhesive strength between the insulating layer and the metal wiring is high. In order to sufficiently hold the metal wiring, the adhesive strength is preferably 4 N / cm or more. Moreover, in the said insulating layer, it is desired that a dimension does not change a lot with heat. That is, it is desirable that the insulating layer has a low coefficient of linear expansion.

However, if only a conventional resin composition as described in Patent Document 1 is used, it is difficult to sufficiently increase the adhesive strength between the cured product obtained by curing the resin composition and the metal wiring. Furthermore, the dimensional change due to heat of the cured product may not be sufficiently reduced, and the linear expansion coefficient of the insulating layer may be relatively high.

An object of the present invention is to provide a laminate capable of increasing the adhesive strength between a cured product and a metal layer, a method for producing the laminate, and a multilayer substrate using the laminate.

A limited object of the present invention is to provide a laminate and a method for producing the laminate that can reduce the dimensional change due to heat of the cured product, and to provide a multilayer substrate using the laminate. .

According to a wide aspect of the present invention, there is provided a cured product obtained by curing an epoxy resin material containing an epoxy resin, a curing agent, and an inorganic filler, and a metal layer laminated on the surface of the cured product, Some are embedded in the cured product at a plurality of locations, the maximum depth of the plurality of metal layer portions embedded in the cured product is 0.5 μm or more, and the curing There is provided a laminate in which the maximum distance between the plurality of metal layer portions embedded in the object is 0.5 μm or more.

In a specific aspect of the laminate according to the present invention, an average of two depths of two adjacent metal layer portions among the plurality of metal layer portions embedded in the cured product is D μm, When the interval between the two metal layer portions is S μm, the minimum of S / D is 0.15 or more in the whole of the plurality of metal layer portions embedded in the cured product, and S / D The maximum is 5.0 or less.

In a specific aspect of the laminate according to the present invention, a plurality of the metal layer portions embedded in the cured product are separated into the cured product by removing the inorganic filler by a roughening treatment. A gap is formed, and a part of the metal layer is embedded in the plurality of gaps.

On the specific situation with the laminated body which concerns on this invention, the said roughening process is a wet roughening process.

In a specific aspect of the laminate according to the present invention, the content of the inorganic filler is 60% by weight or more and 80% by weight or less in the solid content of 100% by weight in the epoxy resin material.

In a specific aspect of the laminate according to the present invention, the average particle diameter of the inorganic filler contained in the epoxy resin material is 0.1 μm or more and 5 μm or less.

According to a wide aspect of the present invention, by using a cured product obtained by curing an epoxy resin material including an epoxy resin, a curing agent, and an inorganic filler, the inorganic filler is desorbed by a roughening treatment, whereby the cured product is obtained. A step of forming a plurality of voids, and a step of forming a metal layer so as to be laminated on the surface of the cured product and partially embedding in the plurality of voids to obtain a laminate, As the laminate, a part of the metal layer is embedded in the cured product at a plurality of locations, and the maximum depth of the plurality of metal layer portions embedded in the cured product is 0. There is provided a method for producing a laminate, which is 5 μm or more and obtains a laminate having a maximum interval of 0.5 μm or more in the whole of the plurality of metal layer portions embedded in the cured product.

In a specific aspect of the method for manufacturing a laminate according to the present invention, the roughening treatment is a wet roughening treatment.

According to a wide aspect of the present invention, there is provided a multilayer board comprising a circuit board and the above-described laminated body, wherein the laminated body is disposed on the surface of the circuit board from the cured product side.

The laminate according to the present invention includes a cured product obtained by curing an epoxy resin material containing an epoxy resin, a curing agent, and an inorganic filler, and a metal layer laminated on the surface of the cured product, and the metal layer Are embedded in the cured product at a plurality of locations, and the maximum depth of the plurality of metal layer portions embedded in the cured product is 0.5 μm or more, and Since the maximum distance between the plurality of metal layer portions embedded in the cured product is 0.5 μm or more, the adhesive strength between the cured product and the metal layer can be increased.

FIG. 1 is a cross-sectional view schematically showing a laminate according to an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing a multilayer substrate using the laminate according to one embodiment of the present invention. FIG. 3 is a schematic cross-sectional view for explaining the depth and interval of the metal layer portion in the laminated body according to one embodiment of the present invention.

Hereinafter, the details of the present invention will be described.

(Laminate)
The laminated body which concerns on this invention is equipped with the hardened | cured material which hardened the epoxy resin material containing an epoxy resin, a hardening | curing agent, and an inorganic filler, and the metal layer laminated | stacked on the surface of the said hardened | cured material. In the laminate according to the present invention, a part of the metal layer is embedded in the cured product at a plurality of locations, and 1) the depth of the entire plurality of the metal layer portions embedded in the cured product. 2), and 2) the maximum interval between the plurality of metal layer portions embedded in the cured product is 0.5 μm or more.

The manufacturing method of the laminated body which concerns on this invention uses the hardened | cured material which hardened | cured the epoxy resin material containing an epoxy resin, a hardening | curing agent, and an inorganic filler, and desorbed the said inorganic filler by a roughening process, and the said hardening Forming a plurality of voids in a product, and forming a laminate by forming a metal layer so as to be stacked on the surface of the cured product and partially embedding in the plurality of voids. Prepare. In the method for manufacturing a laminate according to the present invention, as the laminate, a part of the metal layer is embedded in the cured product at a plurality of locations, and the plurality of metal layers are embedded in the cured product. A laminate having a maximum depth of 0.5 μm or more in the entire portion and a maximum distance of 0.5 μm or more in the entirety of the plurality of metal layer portions embedded in the cured product is obtained. .

By adopting the above-described configuration in the laminate according to the present invention and the method for producing the laminate according to the present invention, the adhesive strength between the cured product and the metal layer can be increased. Furthermore, in the laminate according to the present invention, the dimensional change due to heat of the cured product can be made sufficiently small, and the linear expansion coefficient of the cured product can be made sufficiently low.

1) the maximum depth of the whole of the plurality of metal layer portions embedded in the cured product, and 2) the maximum distance of the plurality of the metal layer portions embedded in the cured product. Can be determined by evaluating the metal layer portion embedded in the cured layer in cross-sectional observation in the thickness direction of the cured product (see FIG. 1).

With respect to each depth of the plurality of metal layer portions embedded in the cured product in order to obtain the maximum depth of 1), the metal layer portion embedded in one of the cured products The depth from the interface between the cured product and the metal layer (excluding the portion where the metal layer is embedded in the cured product) to the deepest embedded portion is defined as the depth.

In order to obtain the maximum of the interval of 2) above, the metal layer portions embedded in the two adjacent cured products with respect to the intervals of the plurality of metal layer portions embedded in the cured product. , The distance from one embedding center portion to the embedding center portion adjacent to the embedding center portion is defined as the interval between the plurality of metal layer portions embedded in the cured product. In addition, the said center part is a center part of the said metal layer part in the interface of the said hardened | cured material and the said metal layer. When determining the central portion, the internal metal layer portion that does not appear at the interface between the cured product and the metal layer is not considered. Each space | interval of the said several metal layer part is each space | interval of two adjacent metal layer parts among the said several metal layer parts embedded in the said hardened | cured material.

1) As a method for controlling the maximum depth of the whole of the plurality of metal layer portions embedded in the cured product within the above-described range, a method for optimizing the type and content of the inorganic filler, and Examples thereof include a method for optimizing the production conditions (crimping and curing conditions) of the laminate.

Regarding the inorganic filler, the depth and interval of the embedded metal layer can be controlled within the above range by setting the average particle size to 0.5 to 1.0 μm and the content to 60 to 80%. Further, by adjusting the pressure bonding conditions, it is possible to prevent the inorganic filler from flowing out, to control the amount of the inorganic filler on the surface layer, and to set the depth and interval of the embedded metal layer within the above range. As for the curing conditions, if the curing is excessive, the roughening cannot be performed. If the curing is not progressing, the depth and interval of the metal layer cannot be controlled within the above range due to the damage due to the roughening treatment. By adjusting the degree of curing, the depth and interval of the buried metal layer can be controlled within the above range. These methods include: 2) a method for controlling the maximum of the interval between the plurality of metal layer portions embedded in the cured product within the above-mentioned range; and 3) the minimum and maximum of S / D. Is also considered as a method of controlling the value within the above-mentioned range.

2) Methods for optimizing the type and content of the inorganic filler, as well as lamination, as a method for controlling the maximum interval between the plurality of metal layer portions embedded in the cured product within the above-mentioned range For example, a method for optimizing the production conditions (crimping and curing conditions) of the body may be used.

From the viewpoint of further increasing the adhesive strength between the cured product and the metal layer, 1) the maximum depth of the plurality of metal layer portions embedded in the cured product is preferably 0.8 μm or more. is there. 1) The maximum upper limit of the depth in the whole of the plurality of metal layer portions embedded in the cured product is not particularly limited. The maximum depth is preferably 5.0 μm or less. When the maximum depth is not more than the above upper limit, the flash etching property is further improved.

From the viewpoint of further increasing the adhesive strength between the cured product and the metal layer, 2) the maximum interval between the plurality of metal layer portions embedded in the cured product is preferably 0.7 μm or more. . 2) There is no particular limitation on the maximum distance between the plurality of metal layer portions embedded in the cured product. The maximum distance is preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 5.0 μm or less. When the maximum of the interval is equal to or less than the upper limit, it is possible to cope with miniaturization of the wiring.

Among the plurality of metal layer portions embedded in the cured product, an average of two depths of two adjacent metal layer portions is D μm, and an interval between the two metal layer portions is S μm. 3) In the whole of the plurality of metal layer portions embedded in the cured product, the minimum S / D is preferably 0.15 or more, and the maximum S / D is preferably 5.0 or less. It is.

3) The minimum and maximum S / D of the plurality of metal layer portions embedded in the cured product is the metal embedded in the cured layer in cross-sectional observation in the thickness direction of the cured product. It can be determined by evaluating the layer portion.

3) In order to obtain the minimum and maximum of S / D, among the plurality of metal layer portions embedded in the cured product, two in the average of the two depths of two adjacent metal layer portions Regarding each depth, in the metal layer portion embedded in one of the cured products, the interface between the cured product and the metal layer (however, the portion where the metal layer is embedded in the cured product is excluded). ) To the deepest embedded portion.

3) In order to obtain the minimum and maximum S / D, among the plurality of metal layer portions embedded in the cured product, each adjacent two metal layer portions are spaced from each other by two adjacent ones. In the metal layer portion embedded in the cured product, the distance from a certain embedding center portion to the embedding center portion adjacent to the embedding center portion is the distance between the metal layer portions embedded in the cured product. And

3) As a method for controlling the minimum and maximum S / D within the above-mentioned range, the method for optimizing the type and content of the inorganic filler and the production conditions (crimping and curing conditions) of the laminate are optimized. And the like.

From the viewpoint of further increasing the adhesive strength between the cured product and the metal layer, 3) The minimum S / D is preferably 0.2 or more. From the viewpoint of further increasing the adhesive strength between the cured product and the metal layer, 3) the maximum S / D is preferably 2.0 or less.

Next, 1) the maximum depth of the whole of the plurality of metal layer portions embedded in the cured product, and 2) the interval between the plurality of the metal layer portions embedded in the cured product. 3) The minimum and maximum S / D will be described with reference to the drawings.

FIG. 1 is a cross-sectional view schematically showing a laminate according to an embodiment of the present invention.

FIG. 1 shows a cross section in the stacking direction of the stacked body 1. The laminate 1 includes a cured product 2 and a metal layer 3 laminated on the surface of the cured product 2. In FIG. 1, the cross section by the thickness direction of hardened | cured material is shown. A part of the metal layer 3 is embedded in the cured product 2 at a plurality of locations A to D. The cured product 2 has a resin portion 2A and an inorganic filler portion 2B. The metal layer 3 has metal layer portions 3a to 3d embedded in the cured product 2 at a plurality of locations A to D.

The depth D1 at the location A, the depth D2 at the location B, the depth D3 at the location C, and the depth D4 at the location D are shown in FIG. Further, the distance S1 of the metal layer portion between the locations A and B, the spacing S2 of the metal layer portion between the locations B and C, and the spacing S3 of the metal layer portion between the locations C and D are given. It was shown in FIG. The depths D1 to D4 are the interfaces between the cured product 2 and the metal layer 3 in the metal layer portions 3a to 3d embedded in the cured product 2 (however, the metal layer 3 is embedded in the cured product 2). This is the depth from the thick line portion L1) in FIG. The intervals S1 to S3 indicate that in the metal layer portions 3a to 3d embedded in the two adjacent cured products 2 from the embedded central portion (thick line portion L2 in FIG. 3) to the embedded central portion adjacent to the embedded central portion. It is the distance to. The intervals between the plurality of metal layer portions 3a to 3d (3a and 3b, 3b and 3c, 3c and 3d) are equal to the two adjacent metal layer portions 3a to 3d embedded in the cured product 2. This is the distance between the metal layer portions 3a to 3d (3a and 3b, 3b and 3c, 3c and 3d). The central portion is the central portion of the metal layer portions 3a to 3d at the interface between the cured product 2 and the metal layer 3. When determining the central portion, the lower portion of the internal metal layer portion 3a that does not appear at the interface between the cured product 2 and the metal layer 3 is not considered (X in FIG. 3).

3) The minimum and maximum S / D can also be obtained from the above-described depths D1 to D4 and the above-described intervals S1 to S3.

When the conventional epoxy resin material contains a large amount of inorganic filler, particularly when the conventional epoxy resin material contains 60 wt% or more of the inorganic filler as a solid content, the dimensional change due to heat of the cured product is reduced. Thus, there is a problem that the adhesive strength between the cured product and the metal layer is lowered.

In contrast, 1) the maximum depth of the whole of the plurality of metal layer portions embedded in the cured product, and 2) the whole of the plurality of metal layer portions embedded in the cured product. In order to reduce the dimensional change due to heat of the cured product by controlling the maximum of the interval in the above, even if the content of the inorganic filler is increased, the solid content of the inorganic filler is 60% by weight or more. Even if it is contained, the adhesive strength between the cured product and the metal layer can be increased. Further, by controlling the 3) S / D minimum and maximum as described above, the adhesive strength between the cured product and the metal layer can be more effectively increased.

When the content of the inorganic filler in 100% by weight of solid content (hereinafter sometimes referred to as solid content A) contained in the epoxy resin material is 60% by weight or more, the heat of the cured product The dimensional change due to is considerably reduced.

Further, a pattern forming method represented by a semi-active method (SAP) is known. In SAP, a circuit pattern (such as Cu plating) is formed in a convex shape on the surface of an insulating layer. Next, another insulating layer is laminated on the insulating layer and the circuit pattern. In SAP, when the content of the inorganic filler in the conventional epoxy resin material is increased, the content of the resin component is relatively decreased, the contact area between the resin component and the circuit is decreased, and the cured product and the circuit There exists a tendency for the adhesive strength of to become low.

In contrast, 1) the maximum depth of the whole of the plurality of metal layer portions embedded in the cured product, and 2) the whole of the plurality of metal layer portions embedded in the cured product. By controlling the maximum interval in the above as described above, even when the insulating layer and the circuit pattern (metal layer) are formed by SAP, the content of the inorganic filler contained in the epoxy resin material used for SAP Even if it increases, the adhesive strength of hardened | cured material and a metal layer can be raised. Further, by controlling the 3) S / D minimum and maximum as described above, the adhesive strength between the cured product and the metal layer can be more effectively increased.

The average linear expansion coefficient of the cured product is preferably 30 ppm / ° C. or less, more preferably 20 ppm / ° C. or less. When the average linear expansion coefficient is equal to or lower than the upper limit, the average thermal linear expansion coefficient of the circuit board is reduced, so that the warpage of the circuit board itself is suppressed and the adhesive strength between the cured product and the metal layer is further improved.

The glass transition temperature of the cured product is preferably 150 ° C. or higher, more preferably 180 ° C. or higher, preferably 250 ° C. or lower, more preferably 200 ° C. or lower. When the glass transition temperature is not less than the above lower limit and not more than the above upper limit, the impact resistance is further improved.

The minimum melt viscosity at 50 to 150 ° C. of the epoxy resin material is preferably 5 Pa · s or more, more preferably 10 Pa · s or more, preferably 300 Pa · s or less, more preferably 250 Pa · s or less, and further preferably 100 Pa. -S or less. When the minimum melt viscosity is not less than the above lower limit and not more than the above upper limit, the handleability of the B stage film is further improved. Moreover, when the minimum melt viscosity is not less than the above lower limit and not more than the above upper limit, for example, when swelling treatment is performed under the swelling treatment conditions described later, or roughening treatment is performed under the roughening treatment conditions described later, 1) 2) It becomes even easier to obtain a cured product in which the maximum depth and the maximum distance of the plurality of metal layer portions embedded in the cured product are each 0.5 μm or more, and 3) It becomes even easier to obtain a cured product having a minimum S / D of 0.15 or more and a maximum of 5.0 or less, and the presence state of the inorganic filler portion near the interface between the resin portion and the metal layer is further increased. As a result, it is easy to make the adhesive strength between the cured product and the metal layer 4 N / cm or more.

The melt viscosity is measured in a temperature range of 50 to 150 ° C. of the epoxy resin material using a Rheometer device. Examples of the Rheometer device include “AR-2000” manufactured by TA Instruments.

The epoxy resin material may be in the form of a paste or a film. The epoxy resin material may be a resin composition or a B-stage film in which the resin composition is formed into a film.

Hereinafter, details of each component such as an epoxy resin, a curing agent and an inorganic filler contained in the epoxy resin material will be described.

[Epoxy resin]
The epoxy resin contained in the epoxy resin material 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.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, biphenyl type epoxy resin, biphenyl novolac type epoxy resin, biphenol type epoxy resin, and naphthalene type epoxy resin. Fluorene type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, anthracene type epoxy resin, epoxy resin having adamantane skeleton, epoxy resin having tricyclodecane skeleton, and triazine nucleus Examples thereof include an epoxy resin having a skeleton.

The epoxy resin preferably has a biphenyl skeleton, and is preferably a biphenyl type epoxy resin. When the said epoxy resin has biphenyl frame | skeleton, the adhesive strength of hardened | cured material and a metal layer becomes still higher.

From the viewpoint of further reducing the surface roughness of the roughened cured product and further increasing the adhesive strength between the cured product and the metal layer, the epoxy equivalent of the epoxy resin is preferably 90 or more, more preferably 100 or more, preferably 1000 or less, more preferably 800 or less.

The molecular weight of the epoxy resin is preferably 1000 or less. In this case, even if the content of the inorganic filler in the epoxy resin material is 60% by weight or more, an epoxy resin material that is a resin composition having high fluidity can be obtained. For this reason, when a B stage film is laminated on a board | substrate, an inorganic filler can be made to exist uniformly.

The molecular weight of the epoxy resin and the molecular weight of the curing agent described below can be calculated from the structural formula when the epoxy resin or the curing agent is not a polymer and when the structural formula of the epoxy resin or the curing agent can be specified. Means. Moreover, when the said epoxy resin or a hardening | curing agent is a polymer, a weight average molecular weight is meant. The said weight average molecular weight shows the weight average molecular weight in polystyrene conversion calculated | required by a gel permeation chromatography (GPC) measurement.

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

As the curing agent, cyanate ester compound (cyanate ester curing agent), phenol compound (phenol curing agent), amine compound (amine curing agent), thiol compound (thiol curing agent), imidazole compound, phosphine compound, acid anhydride, Examples include 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 a cyanate ester compound or a phenol compound. The curing agent is preferably a cyanate ester compound, 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.

From the viewpoints of further reducing the surface roughness of the roughened cured product, further increasing the adhesive strength between the cured product and the metal layer, and forming finer wiring on the surface of the cured product, the above-mentioned curing is performed. The agent is preferably a cyanate ester compound, a phenol compound or an active ester compound.

The use of the cyanate ester compound further increases the glass transition temperature of the cured product of the B stage film having a large content of inorganic filler. The cyanate ester compound is not particularly limited. A conventionally known cyanate ester compound can be used as the cyanate ester compound. As for the said cyanate ester compound, only 1 type may be used and 2 or more types may be used together.

Examples of the cyanate ester compounds include novolak type cyanate ester resins, bisphenol type cyanate ester resins, and prepolymers in which these are partly trimerized. As said novolak-type cyanate ester resin, a phenol novolak-type cyanate ester resin, an alkylphenol-type cyanate ester resin, etc. are mentioned. Examples of the bisphenol type cyanate ester resin include bisphenol A type cyanate ester resin, bisphenol E type cyanate ester resin, and tetramethylbisphenol F type cyanate ester resin.

Commercially available products of the above-mentioned cyanate ester compounds include phenol novolac type cyanate ester resins (Lonza Japan “PT-30” and “PT-60”), and prepolymers (Lonza Japan) in which bisphenol type cyanate ester resins are trimmed. "BA-230S", "BA-3000S", "BTP-1000S" and "BTP-6020S") manufactured by the company.

The use of the above phenol compound further increases the adhesive strength between the cured product and the metal layer. Further, by using the phenol compound, for example, when the surface of copper provided on the surface of the cured product of the resin composition is blackened or Cz-treated, the adhesive strength between the cured product and copper is further increased. Become.

The phenol compound is not particularly limited. A conventionally well-known phenol compound can be used as this phenol compound. As for the said phenol compound, only 1 type may be used and 2 or more types may be used together.

Examples of the phenol compound include novolak type phenol, biphenol type phenol, naphthalene type phenol, dicyclopentadiene type phenol, aralkyl type phenol, and dicyclopentadiene type phenol.

Examples of commercially available phenol compounds include novolak-type phenols (“TD-2091” manufactured by DIC), biphenyl novolac-type phenols (“MEH-7851” manufactured by Meiwa Kasei Co., Ltd.), and aralkyl-type phenol compounds (“MEH manufactured by Meiwa Kasei Co., Ltd.). -7800 "), and phenols having an aminotriazine skeleton (" LA1356 "and" LA3018-50P "manufactured by DIC).

From the viewpoint of further reducing the surface roughness of the surface of the roughened cured product, further increasing the adhesive strength between the cured product and the metal layer, and forming finer wiring on the surface of the cured product, the above phenol is used. The compound is preferably a biphenyl novolac type phenol compound or an aralkyl type phenol compound.

The use of the active ester compound reduces the dielectric loss tangent of a cured product having a relatively large inorganic filler content, thereby improving the transmission loss of the circuit board. The active ester compound is not particularly limited. A conventionally known active ester compound can be used as the active ester compound. As for the said active ester compound, only 1 type may be used and 2 or more types may be used together.

Examples of commercially available active ester compounds include “HPC-8000” manufactured by DIC.

The surface roughness of the roughened cured product is further reduced, the adhesive strength between the cured product and the metal layer is further increased, finer wiring is formed on the surface of the cured product, and good by the curing agent. From the viewpoint of imparting excellent insulation reliability, the curing agent preferably contains a curing agent having an equivalent weight of 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 compound, a phenolic hydroxyl group equivalent when the curing agent is a phenol compound, and the curing agent is an active ester compound. Is the active ester group equivalent.

The molecular weight of the curing agent is preferably 1000 or less. In this case, even if the content of the inorganic filler in the epoxy resin material is 60% by weight or more, an epoxy resin material that is a resin composition having high fluidity can be obtained. For this reason, when a B stage film is laminated on a board | substrate, an inorganic filler can be made to exist uniformly.

The total content of the epoxy resin and the curing agent is preferably 100% by weight of solid content excluding the inorganic filler contained in the epoxy resin material (hereinafter sometimes referred to as solid content B). Is 75% by weight or more, more preferably 80% by weight or more, preferably 99% by weight or less, more preferably 97% by weight or less.

When the total content of the epoxy resin and the curing agent is not less than the above lower limit and not more than the above upper limit, an even better cured product can be obtained and the melt viscosity can be adjusted, so that the dispersibility of the inorganic filler And the B stage film can be prevented from spreading in an unintended region during the curing process. Furthermore, the dimensional change by the heat | fever of hardened | cured material can be suppressed further. In addition, when the total content of the epoxy resin and the curing agent is equal to or more than the lower limit, the melt viscosity does not become too low, and the epoxy resin material tends not to wet excessively in unintended areas during the curing process. There is. Moreover, when the total content of the epoxy resin and the curing agent is not more than the above upper limit, embedding into holes or irregularities in the circuit board is facilitated, and the inorganic filler tends not to exist unevenly. . “Solid content B” refers to the sum of the epoxy resin, the curing agent, and other solid components blended as necessary. The solid content B does not contain an inorganic filler. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

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 epoxy resin material is not particularly limited. Conventional inorganic fillers 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, and boron nitride. The surface roughness of the roughened cured product is reduced, the adhesive strength between the cured product and the metal layer is further increased, finer wiring is formed on the surface of the cured product, and better insulation is achieved by the cured product. From the viewpoint of imparting reliability, the inorganic filler is preferably silica or alumina, more preferably silica, and still more preferably fused silica. By using silica, the linear expansion coefficient of the cured product is further reduced, the surface roughness of the surface of the roughened cured product is effectively reduced, and the adhesive strength between the cured product and the metal layer is effectively increased. . The shape of silica is preferably substantially spherical.

The average particle diameter of the inorganic filler is preferably 0.1 μm or more, preferably 10 μm or less, more preferably 5 μm or less. The average particle size of the inorganic filler is particularly preferably 0.1 μm or more and 5 μm or less. When the average particle diameter is not less than the above lower limit, the embedding property of the epoxy resin material can be improved. When the average particle size is not more than the above upper limit, the surface smoothness of the epoxy resin material which is a B stage film can be improved. Further, when the average particle size is not less than the above lower limit and not more than the above upper limit, for example, when swelling treatment is performed under the swelling treatment conditions described later, or roughening treatment is performed under the roughening treatment conditions described later, 1) 2) It becomes even easier to obtain a cured product in which the maximum depth and the maximum distance of the plurality of metal layer portions embedded in the cured product are each 0.5 μm or more, and 3) It becomes even easier to obtain a cured product having a minimum S / D of 0.15 or more and a maximum of 5.0 or less. As a result, the adhesive strength between the cured product and the metal layer is 4 N / cm or more. Is easy. The inorganic filler may have an average particle size of 0.5 μm or more.

The median diameter (d50) value of 50% is adopted as the average particle diameter of the inorganic filler. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring apparatus.

The inorganic filler is preferably surface-treated, and more preferably surface-treated with a coupling agent. Thereby, the surface roughness of the surface of the roughened cured product is further reduced, the adhesive strength between the cured product and the metal layer is further increased, and finer wiring is formed on the surface of the cured product, and more Better inter-wiring insulation reliability and interlayer insulation reliability can be imparted to the cured product.

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

In the solid content A of 100% by weight contained in the epoxy resin material, the content of the inorganic filler is preferably 50% by weight or more, more preferably 60% by weight or more, preferably 85% by weight or less, more preferably 80% by weight. % Or less. When the content of the inorganic filler is equal to or more than the lower limit, the dimensional change due to heat of the cured product is considerably reduced. Further, when the content of the inorganic filler is not less than the above lower limit and not more than the above upper limit, the surface roughness of the surface of the roughened cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further increased. In addition, finer wiring can be formed on the surface of the cured product, and at the same time, the amount of the inorganic filler can reduce the linear expansion coefficient of the cured product as well as metal copper. “Solid content A” refers to the sum 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.

[Details of other components and epoxy resin materials]
The said epoxy resin material may contain the hardening accelerator as needed. By using a curing accelerator, the curing rate of the epoxy resin material is further increased. By rapidly curing the epoxy resin material, the crosslinked structure of the cured product becomes uniform, the number of unreacted functional groups decreases, and as a result, the crosslinking density increases. 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 ' -Mechi Imidazolyl- (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, 2-phenyl-4-methyl-5-dihydroxymethylimidazole, etc. Can be mentioned.

Examples of the phosphorus compound include triphenylphosphine.

Examples of the amine compound include diethylamine, triethylamine, diethylenetetramine, triethylenetetramine and 4,4-dimethylaminopyridine.

Examples of the organometallic compound include zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), and trisacetylacetonate cobalt (III).

From the viewpoint of increasing the insulation reliability of the cured product, the curing accelerator is particularly preferably an imidazole 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 in the solid content B of 100% by weight is preferably 0.01% by weight or more, more preferably 0.5% by weight or more, preferably It is 3% by weight or less, more preferably 2% by weight or less.

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

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

Examples of the other resins include phenoxy resin, polyvinyl acetal resin, polyphenylene ether resin, divinyl benzyl ether resin, polyarylate resin, diallyl phthalate resin, polyimide resin, amideimide resin, benzoxazine resin, benzoxazole resin, bismaleimide resin, and acrylate. Examples thereof include resins.

(Epoxy resin material that is a B-stage film)
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. And a casting molding method in which a resin composition containing a solvent is cast to form a film, and other conventionally known film molding methods. Especially, since it can respond to thickness reduction, the extrusion molding method or the casting molding method is preferable. The film includes a sheet.

A B-stage film can be obtained by forming the resin composition into a film and drying it by heating at 90 to 200 ° C. for 1 to 180 minutes, for example, to such an extent that curing by heat does not proceed excessively.

The film-like resin composition that can be obtained by the drying process as described above is 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 B-stage film is preferably not a prepreg. When the B stage film is not a prepreg, migration does not occur along a glass cloth or the like. Moreover, when laminating or pre-curing the B stage film, the surface does not have irregularities due to the glass cloth. Moreover, by using the epoxy resin material as a B-stage film that does not contain a prepreg, the dimensional change due to heat of the cured product is reduced, the shape retention is increased, and the semi-additive process suitability is increased.

The above resin composition can be suitably used for forming a laminated film including a base material and a B stage film laminated on one surface of the 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.

(Printed wiring board)
The said epoxy resin material is used suitably in order to form an insulating layer in a printed wiring board.

The printed wiring board can be obtained, for example, by heat-pressing the B stage film using a B stage film formed of the resin composition.

A metal foil can be laminated on one side or both sides of the B-stage film. The method for laminating the B-stage film and the metal foil is not particularly limited, and a known method can be used. For example, the B-stage 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.

(Copper-clad laminate and multilayer board)
The said epoxy resin material is used suitably in order to obtain a copper clad laminated board. 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 B-stage film of this copper-clad laminate is formed from the above epoxy resin material.

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 which hardened | cured epoxy resin material, 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.

The epoxy resin material is preferably used for obtaining a multilayer substrate. As an example of the multilayer substrate, a multilayer substrate including a circuit board and a laminated body laminated on the surface of the circuit board can be given. The laminate in the multilayer substrate includes a cured product and a metal layer laminated on the surface of the cured product. The laminate is disposed on the surface of the circuit board from the cured product side. The cured product is formed by curing the epoxy resin material. It is preferable that the said hardened | cured material is laminated | stacked on the surface provided with the circuit of the circuit board. Part of the cured product is preferably embedded between the circuits. The cured product can be obtained by heating at 100 to 200 ° C. for 1 to 180 minutes, more preferably at 100 to 200 ° C. for 30 to 100 minutes, so that curing by heat does not proceed excessively. When cured under the above preferred heating conditions, for example, when swelling treatment is performed under the swelling treatment conditions described later, or when roughening treatment is performed under the roughening treatment conditions described later, 1) and 2) embedded in the cured product. It is even easier to obtain a cured product having a maximum depth and a maximum distance of 0.5 μm or more in the whole of the plurality of metal layer portions, and 3) the minimum S / D is 0. It becomes even easier to obtain a cured product having 2 or more and a maximum of 5.0 or less, and the presence of the inorganic filler portion in the vicinity of the interface between the resin portion and the metal layer is further improved, resulting in curing. It is easy to set the adhesive strength between the object and the metal layer to 4 N / cm or more.

In the multilayer substrate, it is preferable that the surface of the cured product opposite to the surface on which the circuit substrate is laminated is roughened.

FIG. 2 schematically shows a multilayer substrate using a laminate according to an embodiment of the present invention in a partially cutaway front sectional view.

In the multilayer substrate 11 shown in FIG. 2, multiple layers of cured products 13 to 16 are laminated on the upper surface 12a of the circuit board 12. The cured products 13 to 16 are insulating layers. A metal layer 17 is formed in a partial region of the upper surface 12 a of the circuit board 12. In the cured products 13 to 15 other than the cured product 16 located on the outer surface opposite to the circuit board 12 side among the multiple layers of the cured products 13 to 16, a metal layer 17 is formed in a partial region of the upper surface. Has been. The metal layer 17 is a circuit. Metal layers 17 are respectively arranged between the circuit board 12 and the cured product 13 and between the laminated cured products 13 to 16. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of via hole connection and through hole connection (not shown).

In the multilayer substrate 11, the cured products 13 to 16 are formed by curing the epoxy resin material. In the present embodiment, since the surfaces of the cured products 13 to 16 are roughened, fine holes (not shown) are formed on the surfaces of the cured products 13 to 16. Further, the metal layer 17 reaches the inside of the fine hole. Moreover, in the multilayer substrate 11, the width direction dimension (L) of the metal layer 17 and the width direction dimension (S) of the part in which the metal layer 17 is not formed can be made small. In the multilayer substrate 11, good insulation reliability is imparted between an upper metal layer and a lower metal layer that are not connected by via-hole connection and through-hole connection (not shown).

(Roughening treatment and swelling treatment)
The epoxy resin material is preferably used for obtaining a cured product to be roughened. The cured product includes a precured product that can be further cured.

In order to form fine irregularities on the surface of the precured material obtained by precuring the epoxy resin material, the precured material is preferably roughened. Prior to the roughening treatment, the precured product is preferably subjected to a swelling treatment. The cured product is preferably subjected to a swelling treatment after preliminary curing and before the roughening treatment, and is further cured after the roughening treatment. However, the pre-cured product may not necessarily be subjected to the swelling treatment.

From the viewpoint of further effectively increasing the adhesive strength between the cured product and the metal layer, the roughening treatment is preferably a wet roughening treatment.

As the swelling treatment method, for example, a precured product is treated with an aqueous solution or an organic solvent dispersion of a compound mainly composed of ethylene glycol or the like. The swelling liquid used for the swelling treatment generally contains an alkali as a pH adjuster or the like. The swelling liquid preferably contains sodium hydroxide. Specifically, for example, the swelling treatment is carried out by treating the precured material with a 40 wt% ethylene glycol aqueous solution at a treatment temperature of 30 to 85 ° C. for 1 to 30 minutes. The swelling treatment temperature is preferably in the range of 50 to 85 ° C. When the temperature of the swelling treatment is too low, it takes a long time for the swelling treatment, and the adhesive strength between the cured product and the metal layer tends to be low.

For the roughening treatment, for example, a chemical oxidant such as a manganese compound, a chromium compound, or a persulfate compound is used. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The roughening liquid used for the roughening treatment generally contains an alkali as a pH adjuster or the like. The roughening solution preferably contains sodium hydroxide.

Examples of the manganese compound include potassium permanganate and sodium permanganate. Examples of the chromium compound include potassium dichromate and anhydrous potassium chromate. Examples of the persulfate compound include sodium persulfate, potassium persulfate, and ammonium persulfate.

The method for the roughening treatment is not particularly limited. As the roughening treatment method, for example, 30 to 90 g / L permanganic acid or permanganate solution and 30 to 90 g / L sodium hydroxide solution are used, and the treatment temperature is 30 to 85 ° C. and 1 to 30 minutes. A method of treating a precured material under conditions is preferable. The roughening treatment is preferably performed once or twice. The temperature of the roughening treatment is preferably in the range of 50 to 85 ° C.

By performing the roughening treatment under the above conditions, the resin surface is easily scraped in the range of 0.3 μm or more and 1.5 μm or less in the direction perpendicular to the surface. If the roughening treatment is performed in the above range, 1) and 2) a cured product in which the maximum depth and the maximum interval of the plurality of metal layer portions embedded in the cured product are each 0.5 μm or more is obtained. 3) and it becomes much easier to obtain a cured product having a minimum S / D of 0.2 or more and a maximum of 5.0 or less. As a result, the cured product and metal It is easy to make the adhesive strength with the layer 4 N / cm or more.

When the swelling treatment is performed using the swelling liquid and then the roughening treatment is performed using the roughening liquid, the arithmetic average roughness Ra of the surface of the roughened cured product is preferably 20 nm or more and 350 nm or less. In this case, the adhesive strength between the cured product and the metal layer or wiring is increased, and further finer wiring can be formed on the surface of the cured product.

The adhesive strength between the cured product and the metal layer is preferably 4 N / cm or more. When the adhesive strength is 4 N / cm or more, a metal layer such as a metal wiring can be favorably held on the surface of the cured product.

(Desmear treatment)
Moreover, a through-hole may be formed in the precured material or hardened | cured material obtained by precuring the said epoxy resin material. In the multilayer substrate or the like, a via or a through hole is formed as a through hole. For example, the via can be formed by irradiation with a laser such as a CO ₂ laser. The diameter of the via is not particularly limited, but is about 60 to 80 μm. Due to the formation of the through hole, a smear, which is a resin residue derived from the resin component contained in the cured product, is often formed at the bottom of the via.

In order to remove the smear, the surface of the cured product is preferably desmeared. The desmear process may also serve as a roughening process.

In the desmear treatment, for example, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound is used in the same manner as the roughening treatment. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The desmear treatment liquid used for the desmear treatment generally contains an alkali. The desmear treatment liquid preferably contains sodium hydroxide.

The above desmear treatment method is not particularly limited. As the desmear treatment method, for example, using a 30 to 90 g / L permanganate or permanganate solution and a 30 to 90 g / L sodium hydroxide solution, a treatment temperature of 30 to 85 ° C. and a condition of 1 to 30 minutes A method of treating a precured product or a cured product once or twice is preferable. The temperature of the desmear treatment is preferably in the range of 50 to 85 ° C.

The use of the epoxy resin material sufficiently reduces the surface roughness of the desmeared cured product.

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 components were used.

(Epoxy resin)
Bisphenol A type epoxy resin (“RE-410S” manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 178)
Biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. “NC-3000H”, epoxy equivalent 288)
Dicyclopentadiene type epoxy resin (“XD-1000” manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 254)

(Curing agent)
Active ester compound-containing liquid (“HPC8000-65T” manufactured by DIC, including 65 wt% solids and 35 wt% toluene)
Phenol compound-containing liquid (phenol curing agent having aminotriazine skeleton, “LA3018-50P” manufactured by DIC, hydroxyl group equivalent 151, weight average molecular weight 1000 or less, solid content 50 wt% and propylene glycol monomethyl ether 50 wt%)
Cyanate ester resin-containing liquid (cyanate ester curing agent, prepolymer obtained by triazine conversion of bisphenol A dicyanate, Lonza Japan "BA230S-75", cyanate group equivalent 230, weight average molecular weight 1000 or less, solid 75% by weight and 25% by weight methyl ethyl ketone)

(Inorganic filler)
Silica-containing slurry 1 ("Advertex" SC2050, containing fused silica with an average particle size of 0.5 µm, solid content 70 wt% and cyclohexanone 30 wt%)
Silica-containing slurry 2 ("Advertex Corporation SC4050", containing fused silica with an average particle size of 1.0 µm, solid content 70 wt% and cyclohexanone 30 wt%)
Silica-containing slurry 3 (“SC1050” manufactured by Admatechs, including fused silica with an average particle size of 0.1 μm, containing 70 wt% solids and 30 wt% cyclohexanone)

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

(Other ingredients)

Phenoxy resin-containing liquid ("YX6954-BH30" manufactured by Mitsubishi Chemical Corporation, including weight average molecular weight 39000 in terms of polystyrene, solid content 30% by weight, methyl ethyl ketone 35% by weight and cyclohexanone 35% by weight)

Amidoimide skeleton resin (“SOXR-C” manufactured by Nippon Kogyo Paper Industries Co., Ltd.)

(Example 1)

[Preparation of epoxy resin material]

62.47 parts by weight (solid content 43.73 parts by weight) of the above silica-containing slurry 2 (manufactured by Admatechs, Inc., “SC4050”), and 16.27 parts by weight of an active ester compound-containing liquid (“HPC8000-65T”, manufactured by DIC) (10.58 parts by weight in solids), 2.68 parts by weight (1.34 parts by weight in solids) of phenol compound-containing liquid (“LA3018-50P” manufactured by DIC), and bisphenol A type epoxy resin (Japan) 6.65 parts by weight of “RE-410S” manufactured by Kayaku Co., Ltd., 8.42 parts by weight of biphenyl type epoxy resin (“NC-3000H” manufactured by Nippon Kayaku Co., Ltd.), and an imidazole compound (“2P4MZ manufactured by Shikoku Kasei Kogyo Co., Ltd.) ] 0.50 part by weight and 3.01 part by weight (0.90 part by weight in solid content) of a phenoxy resin-containing liquid (Mitsubishi Chemical "YX6954-BH30") And stirred at room temperature until a uniform liquid, to obtain a resin composition varnish.

[Preparation of Uncured Resin Sheet (B Stage Film) and Precured Material A]

A release-treated transparent polyethylene terephthalate (PET) film (“PET5011 550” manufactured by Lintec Corporation, thickness 50 μm) was prepared. The obtained resin composition varnish was applied onto the PET film using an applicator so that the thickness after drying was 40 μm. Next, it was dried in a gear oven at 100 ° C. for 2 minutes to produce a laminated film of an uncured resin sheet (B stage film) having a thickness of 40 μm and an area of 200 mm × 200 mm and a polyethylene terephthalate film.

Next, the polyethylene terephthalate film was peeled off from the laminated film, and the uncured product of the resin sheet was heated in a gear oven at 180 ° C. for 80 minutes to prepare a precured product A (epoxy resin material) of the resin sheet.

[Preparation of cured product A]

Precured material A of the obtained resin sheet was heated at 190 ° C. for 90 minutes and further cured to obtain cured product A.

(Preparation of precured product B)

The resulting uncured sheet-shaped resin composition was vacuum laminated on a glass epoxy substrate (FR-4, “CS-3665” manufactured by Risho Kogyo Co., Ltd.) and reacted at 150 ° C. for 60 minutes. In this way, a reaction product was formed on the glass epoxy substrate, and a laminated sample of the glass epoxy substrate and the reaction product was obtained. Then, after the following swelling treatment, the following roughening treatment (permanganate treatment) was performed.

Swelling treatment:

The laminated sample was put in a swelling liquid at 80 ° C. (“Swelling Dip Securigant P” manufactured by Atotech Japan Co., Ltd.) and rocked for 10 minutes at a swelling temperature of 80 ° C. Thereafter, it was washed with pure water.

Roughening treatment (permanganate treatment):

The above laminated sample subjected to the swelling treatment was placed in a roughening aqueous solution of potassium permanganate (“Concentrate Compact CP” manufactured by Atotech Japan Co., Ltd.) at 80 ° C. and rocked for 30 minutes at a roughening temperature of 80 ° C. Then, after washing | cleaning for 2 minutes with the washing | cleaning liquid (Atotech Japan Co., Ltd. "Reduction Securigant P"), it wash | cleaned further with the pure water. Thus, the roughened preliminary-cured material B was formed on the glass epoxy substrate.

[Production of Laminate A]

After the roughening treatment, the following copper plating treatment was performed.

Copper plating treatment:

The precured material B formed on the glass epoxy substrate was subjected to electroless copper plating and electrolytic copper plating in the following procedure.

The surface of the roughened preliminary-cured material B was treated with a 60 ° C. alkali cleaner (“Cleaner Securigant 902” manufactured by Atotech Japan) for 5 minutes, and degreased and washed. After washing, the precured product B was treated with a 25 ° C. predip solution (“Predip Neogant B” manufactured by Atotech Japan) for 2 minutes. Thereafter, the precured product B was treated with an activator solution (“Activator Neo Gantt 834” manufactured by Atotech Japan) at 40 ° C. for 5 minutes, and a palladium catalyst was attached. Next, the preliminary-cured product B was treated for 5 minutes with a reducing solution at 30 ° C. (“Reducer Neogant WA” manufactured by Atotech Japan).

Next, the precured product B is placed in a chemical copper solution (“Basic Print Gantt MSK-DK” manufactured by Atotech Japan, “Kappa Print Gantt MSK” manufactured by Atotech Japan, “Stabilizer Print Gantt MSK” manufactured by Atotech Japan). Electroless plating was performed until the plating thickness reached about 0.5 μm. After the electroless plating, annealing was performed at a temperature of 120 ° C. for 30 minutes in order to remove the remaining hydrogen gas. All the processes up to the electroless plating process were performed while the preliminarily cured product B was swung with a processing solution of 1 L on a beaker scale.

Next, electroplating was performed on the precured material B subjected to the electroless plating treatment until the plating thickness became 25 μm. An electric current of 0.6 A / cm ² was passed using copper sulfate (reducer Cu) as the electrolytic copper plating. After the copper plating treatment, the pre-cured product B was heated at 180 ° C. for 1 hour to further cure the pre-cured product B. Thus, the laminated body A in which the copper plating layer was formed on the hardened | cured material was obtained.

(Examples 2 to 8 and Comparative Examples 1 to 3)

The epoxy resin material (preliminarily cured product A), cured product A, and preliminary were prepared in the same manner as in Example 1 except that the types and blending amounts of the components used and the roughening time were set as shown in Table 1 below. A cured product B and a laminate A were produced.

(Evaluation)

(1) In laminate A, the maximum depth of the entire plurality of metal layer portions embedded in the cured product, and the entire plurality of metal layer portions embedded in the cured product in laminate A By observing the cross section of the laminate A with “JSM-6700F” (M × 3000) manufactured by JEOL, a reflected electron image having a size of 40 μm × 30 μm was obtained. This observation was performed in a total area of 5 fields of 1 visual field near the center and 1 visual field each near the 4 edges in the area of the surface of the laminate A of 5 mm × 5 mm. The obtained reflected electron image is an electron image in the direction shown in FIG. In the laminate A, a 40 μm length portion of the interface between the cured product and the metal layer in the obtained reflected electron image was evaluated by measurement on an image with five fields of view. As a result, the maximum depth of the plurality of metal layer portions embedded in the cured product and the maximum distance of the plurality of metal layer portions embedded in the laminate were obtained. . In addition, the maximum depth of the whole of the plurality of metal layer portions embedded in the cured product in the obtained laminate A, and the whole of the plurality of metal layer portions embedded in the laminate. The maximum distance was present in the obtained reflected electron image of 5 fields.

(2) In laminate A, the minimum and maximum of S / D in the whole of the plurality of metal layer portions embedded in the cured product (Evaluation of S / D) The five obtained in the evaluation of (1) above For the electronic image, the average D μm of the two depths and the interval S μm were evaluated to obtain S / D. The obtained S / D was determined according to the following criteria. In addition, in the whole of the plurality of metal layer portions embedded in the cured product in the obtained laminate A, the minimum and maximum S / D are present in the obtained reflected electron image of five fields of view. It was.

[Minimum and Maximum S / D Criteria] A: 0.15 ≦ S / D ≦ 5.0 is satisfied B: 0.15 ≦ S / D ≦ 5.0 is not satisfied

(3) Average linear expansion coefficient of hardened | cured material The obtained hardened | cured material A was cut | judged to the magnitude | size of 3 mm x 25 mm. Using a linear expansion coefficient meter (“TMA / SS120C” manufactured by Seiko Instruments Inc.), the cured product A cut from 0 to 0 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 50 ° C. was measured.

(4) Breaking strength and elongation at break of the cured product The obtained cured product A was cut into a size of 10 mm × 80 mm. Two pieces of the cured product A were laminated to obtain a test sample having a thickness of 80 μm. Using a tensile tester ("Tensilon" manufactured by Orientic Co., Ltd.), a tensile test was performed under the conditions of a distance between chucks of 60 mm and a crosshead speed of 5 mm / min, and the test sample's breaking strength (MPa) and elongation at break (%) ) Was measured.

(5) Glass transition temperature of cured product The obtained cured product A was cut into a size of 10 mm x 80 mm. Using a DMA (dynamic mechanical analysis) apparatus (manufactured by SII Nanotechnology) “EXSTAR6000”, the glass transition temperature of the obtained cured product A was measured under the conditions of a heating rate of 5 ° C./min and a frequency of 10 Hz.

(6) Minimum melt viscosity of epoxy resin material Uncured resin sheet obtained using a Rheometer device ("AR-2000" manufactured by TA Instruments) under the conditions of 21.6% strain and 1 Hz frequency The viscosity of the (B stage film) in the temperature range of 50 to 150 ° C. was measured, and the value at which the viscosity was lowest was taken as the minimum melt viscosity.

(7) Surface roughness (arithmetic average roughness Ra and ten-point average roughness Rz)
Using the non-contact three-dimensional surface shape measuring device (product number “WYKO NT1100”, manufactured by Veeco), the surface of the obtained preliminary-cured product B was subjected to arithmetic average roughness Ra and ten-point average in a measurement area of 94 μm × 123 μm. Roughness Rz was measured.

(8) Plating adhesive strength A 10 mm wide cutout was made on the surface of the copper plating layer of the obtained laminate A. Thereafter, using a tensile tester (“Autograph” manufactured by Shimadzu Corporation), the adhesive strength between the cured product and the copper plating layer was measured under the condition of a crosshead speed of 5 mm / min. The obtained measured value was defined as plating adhesive strength.

(9) Flash etching evaluation Flash etching treatment was performed on the precured material B on which electroless copper plating was applied. As the etchant, “SAC” manufactured by Ebara Eugene Corporation was used. Processing temperature 30 ° C., SAC formulation (35 wt% -H ₂ O: 5 vol%, 98 wt% —H ₂ SO ₄ : 5 vol%, Cu: 20 g / L), processing at intervals of 1 minute up to 1 to 3 minutes. went.

Thereafter, the electroless copper plating removability was evaluated by cross-sectional observation of the precured material B with FE-SEM (“JSM-6700F” manufactured by JEOL, M × 3000), and the flash etching property was determined according to the following criteria. .

[Judgment criteria for flash etching properties]
○: Electroless copper plating is removed within 1 minute. △: Electroless copper plating is removed within 3 minutes to 3 minutes. ×: Electroless copper plating is not removed even after 3 minutes.

Composition and results are shown in Table 1 below.

1 ... Laminate

2. Hardened product

2A ... resin part

2B ... Inorganic filler part

3 ... Metal layer

3a to 3d ... Metal layer part

11 ... Multilayer substrate

12 ... Circuit board

12a ... Upper surface

13 to 16 ... Cured product

17 ... Metal layer (wiring)

Claims (9)

1. 
   A cured product obtained by curing an epoxy resin material containing an epoxy resin, a curing agent and an inorganic filler;
   
   A metal layer laminated on the surface of the cured product,
   
   A portion of the metal layer is embedded in the cured product at a plurality of locations;
   
   The maximum depth in the whole of the plurality of metal layer portions embedded in the cured product is 0.5 μm or more, and in the whole of the plurality of metal layer portions embedded in the cured product. A laminate having a maximum interval of 0.5 μm or more.
   
2. 
   Among the plurality of metal layer portions embedded in the cured product, when the average of two depths of two adjacent metal layer portions is D μm and the interval between the two metal layer portions is S μm ,
   
   In the whole of the plurality of metal layer portions embedded in the cured product, the minimum S / D is 0.15 or more, and the maximum S / D is 5.0 or less. The laminated body of description.
3. 
   The plurality of metal layer portions embedded in the cured product are formed by removing the inorganic filler by a roughening process, thereby forming a plurality of voids in the cured product, and the metal layer in the plurality of voids. The laminate according to claim 1, wherein the laminate is formed by embedding a part thereof.
4. 
   The laminate according to claim 3, wherein the roughening treatment is a wet roughening treatment.
5. The laminate according to any one of claims 1 to 4, wherein a content of the inorganic filler is 60% by weight or more and 80% by weight or less in a solid content of 100% by weight in the epoxy resin material.
6. The laminate according to any one of claims 1 to 5, wherein the inorganic filler contained in the epoxy resin material has an average particle size of 0.1 µm or more and 5 µm or less.
7. Using a cured product obtained by curing an epoxy resin material containing an epoxy resin, a curing agent, and an inorganic filler, and removing the inorganic filler by a roughening treatment to form a plurality of voids in the cured product;
   Forming a metal layer so as to be laminated on the surface of the cured product and embedding a part in the plurality of voids, and obtaining a laminate,
   As the laminate, a part of the metal layer is embedded in the cured product at a plurality of locations, and the maximum depth of the plurality of metal layer portions embedded in the cured product is 0. The manufacturing method of a laminated body which obtains the laminated body which is 5 micrometers or more and the maximum of the space | interval in the whole of the said several metal layer part embedded in the said hardened | cured material is 0.5 micrometers or more.
8. The manufacturing method of the laminated body of Claim 7 whose said roughening process is a wet roughening process.
   
9. 
   A circuit board;
   
   A laminate according to any one of claims 1 to 6,
   
   The multilayer board | substrate with which the said laminated body is arrange | positioned on the surface of the said circuit board from the said hardened | cured material side.

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