KR20200097698A - Copper foil with insulating resin layer formed - Google Patents

Abstract

It is an object of the present invention to provide a copper foil with an insulating resin layer that can be preferably used for a thin printed wiring board on which high-density fine wiring is formed and a substrate for mounting a semiconductor element. The copper foil on which the insulating resin layer of the present invention is formed includes a copper foil and an insulating resin layer laminated on the copper foil, and the arithmetic mean roughness (Ra) of the surface of the copper foil in contact with the insulating resin layer is 0.05 to 2 μm, and the The insulating resin layer is made of a resin composition containing (A) a thermosetting resin, (B) a spherical filler, and (C) short glass fibers having an average fiber length of 10 to 300 µm.

Description

Copper foil with insulating resin layer formed

The present invention relates to a copper foil with an insulating resin layer formed thereon. Specifically, the present invention relates to a copper foil provided with an insulating resin layer useful as a build-up material for a printed wiring board or a substrate for mounting semiconductor elements.

[0002] The increase in functionality and miniaturization of semiconductor packages widely used in electronic devices, communication devices, personal computers, and the like has been accelerating in recent years. Along with this, there is a demand for thinner printed wiring boards and substrates for mounting semiconductor elements in semiconductor packages.

As a manufacturing method of a thin printed wiring board and a substrate for mounting a semiconductor element, for example, Patent Document 1 is made of copper that can be peeled off in a subsequent step on a thick support substrate (carrier substrate) with high rigidity such as stainless steel. On the layered laminate, a circuit pattern is formed by pattern plating, an insulating layer such as an epoxy resin coated fiber glass is laminated to heat and pressurize, and finally the support substrate is peeled off and removed to form a thin printed wiring board. Disclosed is a method of manufacturing. In this way, by laminating a circuit pattern and an insulating material on a high rigidity, thick support substrate, and finally peeling and removing the support substrate, it is possible to manufacture a thin printed wiring board and a semiconductor element mounting substrate even with an existing manufacturing apparatus. I can.

In addition, in the multilayer printed wiring board and the semiconductor element mounting board, miniaturization of conductor wiring is progressing in order to improve the mounting density of electronic components. In the conductor wiring, a conductor layer is usually formed by using electroless plating and electrolytic plating on the insulating resin layer. In Patent Document 2, there is a description of a resin composition that can be used for formation of an insulating resin layer of a printed wiring board.

Japanese Patent Publication No. 59-500341 Japanese Unexamined Patent Publication No. 2015-67626

However, in the case of manufacturing a printed wiring board and a substrate for mounting semiconductor elements without using a support substrate for the purpose of thinning, if an existing manufacturing apparatus is used, the printed wiring board and the substrate for mounting semiconductor elements may be broken or printed. Problems such as the wiring board and the substrate for mounting semiconductor elements being wound on a conveyor occur. Therefore, it is difficult to manufacture a printed wiring board and a substrate for mounting semiconductor elements for the purpose of reducing the thickness using an existing manufacturing apparatus.

In addition, what is specifically disclosed in Patent Document 2 is an adhesive film formed by forming a layer composed of a resin composition on a film of polyethylene terephthalate (hereinafter, sometimes referred to as "PET") as a support. In Patent Document 2, the PET film is peeled from this adhesive film, and thereafter, the resin composition is cured to form an insulating resin layer (insulating layer), and this insulating resin layer is used for a printed wiring board.

However, since the surface roughness of the insulating resin layer after curing is low, the adhesion with the conductor layer formed using electroless plating and/or electrolytic plating is low. Therefore, in order to obtain adhesiveness, roughening treatment such as desmear treatment is usually performed on the insulating resin layer before electroless plating or electrolytic plating. On the surface of the insulating resin layer subjected to the roughening treatment, inorganic substances such as glass fibers in the resin composition are exposed (protruded), and the surface is rough. In addition, there is also a problem that large depressions are formed in the insulating resin layer by the inorganic material falling out of the insulating resin layer. In addition, since inorganic substances such as glass fibers are exposed from the surface of the hole, when forming a multilayer printed wiring board (hereinafter, sometimes referred to as ``BVH'') using a laser processing machine, abnormal precipitation of plating or BVH There is also a problem that connection reliability deteriorates. It is difficult to form high-density fine wiring on the surface of such an insulating resin layer, and it is difficult to manufacture a printed wiring board with high-density fine wiring and a substrate for mounting a semiconductor element from the adhesive film in Patent Document 2.

The present invention has been made in view of such a problem, and is made of copper foil with an insulating resin layer that can be preferably used in the manufacture of a thin printed wiring board with high-density fine wiring and good through holes and a substrate for mounting semiconductor elements. It is for the purpose of providing.

The present inventors, as a result of repeated intensive studies in order to solve the above problems, resulted in a laminated insulating resin layer having high rigidity and excellent adhesion to the insulating resin layer on a copper foil having high adhesion to the copper foil and high toughness. By using the copper foil on which the formation layer was formed, it was found that high-density fine wiring was formed and a thin printed wiring board and a semiconductor element mounting substrate with good through holes formed could be obtained, and the present invention was completed.

That is, the present invention is as follows.

(1) A copper foil and an insulating resin layer laminated on the copper foil, the arithmetic mean roughness (Ra) of the surface of the copper foil in contact with the insulating resin layer is 0.05 to 2 µm, and the insulating resin layer is (A) A copper foil with an insulating resin layer formed of a resin composition containing a thermosetting resin, (B) a spherical filler, and (C) short glass fibers having an average fiber length of 10 to 300 µm.

[2] The copper foil according to [1], wherein the insulating resin layer has a thickness of 3 to 50 µm.

[3] The copper foil according to [1] or [2], wherein the thickness of the copper foil is 1 to 18 µm.

[4] The copper foil according to any one of [1] to [3], wherein the fiber diameter of the short glass fibers is 1 to 15 µm.

[5] The copper foil according to any one of [1] to [4], wherein the content of the short glass fibers is 5 to 450 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition.

[6] The copper foil according to any one of [1] to [5], wherein the short glass fibers are milled fibers.

[7] The copper foil according to any one of [1] to [6], wherein the content of the spherical filler is 50 to 500 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition.

(8) The thermosetting resin is an epoxy resin, a cyanate ester compound, a maleimide compound, a phenol resin, a thermosetting modified polyphenylene ether resin, a benzoxazine compound, an organic group-modified silicone compound, and a compound having a polymerizable unsaturated group. The copper foil according to any one of [1] to [7], containing at least one selected from the group consisting of.

[9] The copper foil according to any one of [1] to [8], for use as a build-up material for a printed wiring board or a substrate for mounting semiconductor elements.

According to the present invention, a copper foil having an insulating resin layer in which an insulating resin layer having high adhesion strength between a copper foil and an insulating resin layer is high, and an insulating resin layer having high toughness is laminated on the copper foil can be preferably obtained. By using the copper foil with the insulating resin layer of the present invention, it is possible to obtain a thin printed wiring board and a semiconductor element mounting substrate in which high-density fine wiring is formed and good conductive holes are formed.

Moreover, even if plating treatment is performed after etching the copper foil at the time of manufacturing a printed wiring board or a substrate for mounting a semiconductor element, since the surface of the copper foil is transferred to the insulating resin layer, the adhesion between the insulating resin layer and the plating is improved.

1 is a schematic diagram showing a surface state of a through hole when a hole is drilled in a printed wiring board using laser processing.
2 is an SEM image of the surface of the opening after laser processing (Example 1).
3 is an SEM image of the surface of the opening after laser processing (Comparative Example 3).

Hereinafter, an embodiment for carrying out the present invention (hereinafter, simply referred to as "the present embodiment") will be described in detail, but the present invention is not limited to the following present embodiment. The present invention can be variously modified without departing from the gist of the present invention. In the present specification, in the laminate, each layer is adhered to each other, but the respective layers may be peelable from each other as necessary.

In this embodiment, the term "resin solid content" or "resin solid content in the resin composition" refers to a component excluding a solvent and a filler in the resin composition, unless otherwise specified, and "resin solid content 100 parts by mass" refers to resin It means that the total of the components excluding the solvent and the filler in the composition is 100 parts by mass.

[Copper foil with insulating resin layer formed]

The copper foil on which the insulating resin layer of the present embodiment was formed is obtained by laminating an insulating resin layer made of a resin composition on the copper foil. In the copper foil of this embodiment, the arithmetic mean roughness Ra of the copper foil surface in contact with the insulating resin layer is 0.05 to 2 µm. The resin composition of the present embodiment contains (A) a thermosetting resin, (B) a spherical filler, and (C) short glass fibers having an average fiber length of 10 to 300 µm.

In this embodiment, since an insulating resin layer having high adhesion to copper foil and high toughness is laminated on a copper foil having high rigidity and excellent adhesion to the insulating resin layer, the copper foil provided with the insulating resin layer of this embodiment is used. Even if the printed wiring board is manufactured by doing so, in the manufacturing process, the thin insulating resin layer is not destroyed, and the copper foil and the insulating resin layer are not peeled off. Further, it is possible to form a conductive hole of a good shape.

The copper foil provided with the insulating resin layer of the present embodiment can be used for manufacturing electronic devices, communication devices, personal computers, and the like, and is useful as a build-up material for a printed wiring board or a substrate for mounting semiconductor elements. When the copper foil with the insulating resin layer of the present embodiment is used as the build-up material for the printed wiring board and the semiconductor element mounting substrate, the copper foil can be laminated on the outermost surface of the printed wiring board and the semiconductor element mounting substrate. With respect to copper foil, an integrated circuit pattern can be formed. Moreover, even if plating treatment is performed after etching the copper foil at the time of manufacturing a printed wiring board or a substrate for mounting a semiconductor element, since the surface of the copper foil is transferred to the insulating resin layer, the adhesion between the insulating resin layer and the plating is improved. Therefore, by using the copper foil on which the insulating resin layer of the present embodiment is formed, a thin printed wiring board and a semiconductor element mounting substrate with high-density fine wiring can be obtained.

〔Copper foil〕

The copper foil of the present embodiment is not particularly limited as long as it is a copper foil or a copper film used for an ordinary printed wiring board, and the arithmetic mean roughness (Ra) of the copper foil surface in contact with the insulating resin layer is 0.05 to 2 µm. As a specific example of a copper foil, an electrolytic copper foil, a rolled copper foil, and a copper alloy film are mentioned. The copper foil or copper film may be subjected to known surface treatments such as mat treatment, corona treatment, nickel treatment, and cobalt treatment, for example.

The arithmetic average roughness (Ra) of the copper foil surface is usually in the range of 0.05 to 2 µm, and 0.08 from the viewpoint of improving the adhesion strength between the copper foil and the insulating resin layer and preventing peeling of the layer in long-term use. It is preferable that it is in the range of -1.7 micrometers, and it is more preferable that it is the range of 0.2-1.6 micrometers from the point which can obtain more excellent adhesiveness between a copper foil and an insulating resin layer. In the present embodiment, the copper foil with an insulating resin layer comprising copper foil having an arithmetic average roughness in the above range can be preferably used for manufacturing a printed wiring board with high-density fine wiring and a substrate for mounting semiconductor elements. In addition, if the arithmetic mean roughness is less than 0.05 µm, there is a fear that adhesion strength between the copper foil and the resin may not be obtained, and if it exceeds 2 µm, lower residues are likely to occur during wiring formation, and fine wiring cannot be formed. There is concern. In addition, the arithmetic mean roughness can be measured using a commercially available shape measuring microscope (laser microscope, for example, VK-X210 (brand name) manufactured by Keyence Corporation). The specific measurement method is as described in Examples.

The thickness of the copper foil is not particularly limited as long as the effect of the present embodiment is exhibited, but the range of 1 to 18 µm is preferable, and a thin printed wiring board and a semiconductor element mounting substrate can be preferably obtained. It is more preferable that it is a range of -15 micrometers. When the thickness of the copper foil is less than 1 µm, roughening treatment on the surface of the copper foil becomes difficult, and when it exceeds 18 µm, the cost or hole workability becomes disadvantageous.

As a copper foil, for example, JX Metal Co., Ltd. GHY5 (brand name, 12 µm-thick copper foil), Mitsui Metal Mining Co., Ltd. 3EC-VLP (brand name, 12 µm-thick copper foil), 3EC-III (brand name , 12 μm thick copper foil) and 3EC-M2S-VLP (brand name, 12 μm thick copper foil), copper foil GTS-MP (brand name, 12 μm thick copper foil) manufactured by Furukawa Electric Heung-up Co., Ltd. and JXUT manufactured by JX Metals Inc. A commercial item of -I (brand name, 1.5 µm-thick copper foil) can be used.

[Resin composition]

(A) thermosetting resin

The resin composition of this embodiment contains a thermosetting resin in terms of heat resistance, insulation, and plating adhesion. The thermosetting resin is not particularly limited as long as it is a resin used for an insulating layer of a printed wiring board.

Specific examples of the thermosetting resin include an epoxy resin, a cyanate ester compound, a maleimide compound, a phenol resin, a thermosetting modified polyphenylene ether resin, a benzoxazine compound, an organic group-modified silicone compound, and a compound having a polymerizable unsaturated group. Can be lifted.

These thermosetting resins can be used alone or in combination of two or more as appropriate.

Among these thermosetting resins, from the viewpoint of obtaining an insulating resin layer having excellent peel strength, the resin composition preferably contains an epoxy resin and a cyanate ester compound, and together with an epoxy resin and a cyanate ester compound, a bismaleimide compound It is more preferable to further contain.

The epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule, and any conventionally known epoxy resin can be used.

The epoxy equivalent of the epoxy resin is preferably 250 to 850 g/eq, and more preferably 250 to 450 g/eq, from the viewpoint of making adhesiveness and flexibility more favorable. The epoxy equivalent can be measured by a conventional method.

Specific examples of the epoxy resin include, for example, polyoxynaphthylene type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene tetrafunctional type epoxy resin, xylene type epoxy resin, naphthol aralkyl type epoxy resin, bisphenol A type Epoxy resin, bisphenol F type epoxy resin, bisphenol A novolak type epoxy resin, trifunctional phenol type epoxy resin, tetrafunctional phenol type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, aralkyl novolak type epoxy resin, Reaction of alicyclic epoxy resin, polyol type epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, compound obtained by epoxidation of double bonds such as butadiene, hydroxyl group-containing silicone resins and epichlorohydrin The compound obtained by is mentioned. Among these, polyoxynaphthylene-type epoxy resin, biphenylaralkyl-type epoxy resin, naphthalene tetrafunctional epoxy resin, xylene-type epoxy resin, and naphthol aralkyl-type epoxy resin are preferred from the viewpoints of plating copper adhesion and flame retardancy. Do. These epoxy resins can be used alone or in combination of two or more as appropriate.

In the present embodiment, the content of the epoxy resin is not particularly limited, but from the viewpoint of heat resistance and curability, the range of 10 to 80 parts by mass is preferable, and 30 to 70 parts by mass per 100 parts by mass of the resin solid content in the resin composition. The range is particularly preferred.

Since the cyanate ester compound has excellent properties such as chemical resistance and adhesiveness, and can form a uniform roughened surface due to its excellent chemical resistance, it can be preferably used as a component of the resin composition of the present embodiment. have.

As a specific example of a cyanate ester compound, for example, an α-naphthol aralkyl type cyanate ester compound represented by formula (1), a novolac type cyanate ester compound represented by formula (2), and formula (3) The biphenylaralkyl type cyanate ester compound shown, 1,3-dicyanatobenzene, 1,4-dicyanatobenzene, 1,3,5-tricyanatobenzene, bis(3,5-dimethyl 4-cyanato) Phenyl)methane, 1,3-dicyanatonaphthalene, 1,4-dicyanatonaphthalene, 1,6-dicyanatonaphthalene, 1,8-dicianatonaphthalene, 2,6-dicyanatonaphthalene, 2 ,7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4'-dicyanatobiphenyl, bis(4-cyanatophenyl)methane, bis(4-cyanatophenyl)propane, bis( 4-cyanatophenyl)ether, bis(4-cyanatophenyl)thioether, bis(4-cyanatophenyl)sulfone, 2,2'-bis(4-cyanatophenyl)propane, bis(3,5- Dimethyl-4-cyanatophenyl)methane. These cyanate ester compounds can be used alone or in combination of two or more as appropriate.

Among these, α-naphthol aralkyl type cyanate ester compound represented by formula (1), novolak type cyanate ester compound represented by formula (2), and biphenylaralkyl type cyanate ester compound represented by formula (3) It is preferable from the viewpoint of excellent flame retardancy, high curability, and low thermal expansion coefficient of the cured product.

[Formula 1]

(In formula (1), R ¹ represents a hydrogen atom or a methyl group, and n ¹ represents an integer of 1 or more. It is preferable that n ¹ is an integer of 1 to 50.)

[Formula 2]

(In formula (2), R ² represents a hydrogen atom or a methyl group, and n ² represents an integer of 1 or more. It is preferable that n ² is an integer of 1 to 50.)

[Chemical Formula 3]

(In formula (3), R ³ represents a hydrogen atom or a methyl group, and n ³ represents an integer of 1 or more. It is preferable that n ³ is an integer of 1 to 50.)

In the present embodiment, the content of the cyanate ester compound is not particularly limited, but from the viewpoint of heat resistance and adhesion with copper foil, the range of 15 to 85 parts by mass is preferable with respect to 100 parts by mass of the resin solid content in the resin composition, The range of 25 to 65 parts by mass is more preferable.

Since the maleimide compound can improve the moisture absorption and heat resistance of the insulating resin layer, it can be preferably used as a component of the resin composition of the present embodiment.

The maleimide compound is not particularly limited as long as it has two or more maleimide groups in one molecule, and any conventionally known maleimide compound can be used.

As a specific example of a maleimide compound, for example, bis(4-maleimidephenyl)methane, 2,2-bis{4-(4-maleimidephenoxy)-phenyl}propane, bis(3,5- Bismaleimide compounds such as dimethyl-4-maleimidephenyl)methane, bis(3-ethyl-5-methyl-4-maleimidephenyl)methane, and bis(3,5-diethyl-4-maleimidephenyl)methane ; Polyphenylmethane maleimide is mentioned. Further, it may be blended in the form of a prepolymer of these maleimide compounds or a prepolymer of a maleimide compound and an amine compound. These maleimide compounds can be used alone or in combination of two or more as appropriate.

Among these, from the viewpoint of heat resistance, a bismaleimide compound is preferred, and bis(3-ethyl-5-methyl-4-maleimidephenyl)methane is more preferred.

In the present embodiment, the content of the maleimide compound is not particularly limited, but from the viewpoint of heat resistance and adhesion to copper foil, the range of 5 to 75 parts by mass is preferable with respect to 100 parts by mass of the resin solid content in the resin composition. The range of -45 parts by mass is more preferable.

The phenol resin is not particularly limited as long as it is a resin having two or more phenolic hydroxyl groups in one molecule, and any conventionally known phenol resin can be used.

Specific examples of the phenol resin include, for example, phenol novolak resin, alkylphenol novolak resin, bisphenol A novolac resin, dicyclopentadiene type phenol resin, xylok type phenol resin, terpene-modified phenol resin. , Polyvinylphenols, aralkyl-type phenol resins, and the like, in which a hydrogen atom bonded to an aromatic ring in one molecule is substituted with two or more hydroxyl groups. These phenolic resins can be used alone or in combination of two or more as appropriate.

The thermosetting modified polyphenylene ether resin is a resin obtained by mixing a thermoplastic polyphenylene ether resin and an epoxy resin, dissolving it in a solvent such as toluene, and adding 2-ethyl-4-methylimidazole as a catalyst to crosslink.

The benzoxazine compound is not particularly limited as long as it has an oxazine ring as a basic skeleton. Moreover, in this embodiment, the compound which has a polycyclic oxazine skeleton, such as a naphthooxazine compound, is also contained in a benzoxazine compound.

The organic group-modified silicone compound is not particularly limited, and specific examples include di(methylamino)polydimethylsiloxane, di(ethylamino)polydimethylsiloxane, di(propylamino)polydimethylsiloxane, and di(epoxypropyl) Polydimethylsiloxane and di(epoxybutyl)polydimethylsiloxane. These organic group-modified silicone compounds can be used alone or in combination of two or more as appropriate.

The compound having a polymerizable unsaturated group is not particularly limited, and vinyl compounds such as ethylene, propylene, styrene, divinylbenzene, and divinylbiphenyl; Methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropanedi (meth) acrylate, trimethyl (Meth)acrylates of monohydric or polyhydric alcohols such as allpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; Epoxy (meth)acrylates, such as bisphenol A type epoxy (meth)acrylate and bisphenol F type epoxy (meth)acrylate; Benzocyclobutene resin, etc. are mentioned. These compounds having a polymerizable unsaturated group can be used by appropriately mixing one or two or more.

(B) spherical filler

The resin composition of this embodiment contains a spherical filler in terms of low thermal expansion coefficient, moldability, filling property, and rigidity. The spherical filler is not particularly limited as long as it is a spherical filler used for the insulating layer of a printed wiring board.

The spherical filler is not particularly limited, but the average particle diameter (D50) is preferably in the range of 0.01 to 5 µm. In addition, D50 means a median diameter, and when the particle size distribution of the measured powder is divided into two, the larger one and the smaller one are equivalent diameters. The D50 value of the spherical filler is generally measured by a wet laser diffraction/scattering method.

Examples of the spherical filler include silicas such as magnesium hydroxide, magnesium oxide, natural silica, fused silica, amorphous silica, and hollow silica; Molybdenum compounds such as molybdenum disulfide, molybdenum oxide, and zinc molybdate; Alumina; Aluminum nitride; Glass ; Titanium oxide; Zirconium oxide and the like. These spherical fillers can be used alone or in combination of two or more as appropriate.

As the spherical filler, spherical fused silica is preferable from the viewpoint of low thermal expansion. As commercially available spherical fused silica, SC2050-MB, SC2500-SQ, SC4500-SQ, SO-C2, SO-C1 manufactured by Admatex Co., Ltd., SFP-130MC manufactured by Denki Chemical Industries, etc. Can be lifted.

The average particle diameter of the spherical silica is not particularly limited, but the range of 0.01 µm to 5 µm is preferable, the range of 0.05 µm to 3 µm is more preferable, the range of 0.1 µm to 2 µm is more preferable, and 0.3 µm to 1.5 µm is even more preferable. The average particle diameter of the spherical silica can be measured by a laser diffraction/scattering method based on the Mie scattering theory. Specifically, it can be measured by creating a particle size distribution of spherical silica on a volume basis with a laser diffraction scattering type particle size distribution measuring device, and setting the median diameter to an average particle diameter. The measurement sample can be preferably used in which spherical silica is dispersed in water by ultrasonic waves. As a laser diffraction scattering type particle size distribution measuring device, LA-500 manufactured by Horiba Co., Ltd. can be used.

In this embodiment, the content of the spherical filler is not particularly limited, but from the viewpoint of moldability, the range of 50 to 500 parts by mass is preferable, and the range of 100 to 400 parts by mass per 100 parts by mass of the resin solid content in the resin composition is It is particularly preferred.

Moreover, the spherical filler of this embodiment may be surface-treated with a silane coupling agent or the like. As the silane coupling agent, a silane coupling agent described later can be used.

(C) short glass fibers having an average fiber length of 10 to 300 µm

The resin composition of the present embodiment contains short glass fibers having an average fiber length of 10 to 300 µm in order to obtain a resin composition having excellent adhesion to copper foil, imparting toughness to the resin composition, and a low coefficient of thermal expansion. The short glass fibers of the present embodiment are particularly limited if they mainly contain SiO ₂ , Al ₂ O ₃ , CaO, MgO, B ₂ O ₃ , Na ₂ O and K ₂ O, and the average fiber length is 10 to 300 μm. It doesn't work.

The average fiber length of the short glass fibers is preferably 20 µm or more, and more preferably 30 µm or more, from the viewpoint of lowering the coefficient of thermal expansion. Moreover, from the viewpoint of improving the dispersibility of the short glass fibers, it is preferably 250 µm or less, more preferably 200 µm or less, and even more preferably 150 µm or less.

The fiber diameter of the short glass fibers is not particularly limited, but it is preferably 1 µm or more, more preferably 3 µm or more, and even more preferably 4 µm or more, since the coefficient of thermal expansion can be lowered. From the viewpoint of smoothness, it is preferably 15 µm or less, more preferably 13 µm or less, and even more preferably 11 µm or less.

The average fiber length and fiber diameter of short glass fibers can be measured using an optical microscope or an electron microscope.

Specific examples of the short glass fibers include milled fibers (also referred to as milled fibers in this embodiment), glass wool, and microrods, but when blended into an insulating resin layer, excellent adhesion to copper foil can be obtained. In terms of being inexpensive, milled fibers are preferred. These short glass fibers can be used alone or in combination of two or more as appropriate.

In the present embodiment, the content of the short glass fibers is not particularly limited, but from the viewpoint of the thermal expansion coefficient, the provision of toughness, and the moldability, the range of 5 to 450 parts by mass is preferable with respect to 100 parts by mass of the resin solid content in the resin composition. And the range of 10 to 400 parts by mass is particularly preferred.

In this embodiment, the mixing ratio of (B) spherical filler and (C) short glass fiber is not particularly limited, but from the viewpoint of moldability, the mass ratio of (B) spherical filler: (C) short glass fiber is 1:20 -100:1 is preferable, 1:10-150:1 are more preferable, and 1:2-10:1 are still more preferable.

(Other ingredients)

In addition to (A) thermosetting resin, (B) spherical filler, and (C) short glass fiber, the resin composition of this embodiment may contain other 1 or 2 or more types of components.

As other components, the resin composition of the present embodiment may contain, for example, a silane coupling agent for the purpose of improving the moisture absorption and heat resistance of the insulating resin layer according to the present embodiment. The silane coupling agent is not particularly limited as long as it is a silane coupling agent generally used for surface treatment of inorganic substances. As a specific example, an aminosilane-based silane coupling agent (eg, γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane), an epoxysilane-based silane coupling agent (E.g., γ-glycidoxypropyltrimethoxysilane), vinylsilane-based silane coupling agent (e.g., γ-methacryloxypropyltrimethoxysilane), cationic silane-based silane coupling agent (e.g. For example, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane hydrochloride), a phenylsilane-based silane coupling agent, and the like can be mentioned. These silane coupling agents can be used alone or in combination of two or more as appropriate.

In this embodiment, the content of the silane coupling agent is not particularly limited, but from the viewpoint of improving the moisture absorption and heat resistance, the range of 0.05 to 5 parts by mass is preferable, and the range of 0.1 to 3 parts by mass per 100 parts by mass of the spherical filler is More preferable. Moreover, when using two or more types of silane coupling agents together, it is preferable that these total amount satisfy the said range.

The resin composition of the present embodiment may contain a wetting and dispersing agent for the purpose of improving the manufacturability of the insulating resin layer. The wet dispersant is not particularly limited as long as it is a wet dispersant generally used for paints or the like. As a specific example, Disperbyk (registered trademark)-110, Dong-111, Dong-180, Dong-161, BYK (registered trademark)-W996, Dong-W9010, Dong-W903, etc. manufactured by Big Chemical Japan Co., Ltd. Can be mentioned. These wetting and dispersing agents can be used alone or in combination of two or more as appropriate.

In the present embodiment, the content of the wetting dispersant is not particularly limited, but from the viewpoint of improving the manufacturability of the insulating resin layer, the range of 0.1 to 5 parts by mass is preferable, and 0.5 to 3 parts by mass per 100 parts by mass of the spherical filler. A negative range is more preferable. In addition, when two or more types of wetting and dispersing agents are used in combination, it is preferable that the total amount thereof satisfies the above range.

The resin composition of the present embodiment may contain a curing accelerator for the purpose of adjusting the curing rate or the like. The curing accelerator is not particularly limited as long as it is generally used, such as a curing accelerator used for an epoxy resin or a cyanate ester compound. As specific examples, organic metal salts containing metals such as copper, zinc, cobalt, nickel, manganese, etc. (e.g., zinc octylate, cobalt naphthenate, nickel octylate, manganese octylate), imidazoles, and the like Derivatives (e.g. 2-ethyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 2,4,5-triphenylimidazole), tertiary amines (e.g., Triethylamine, tributylamine) can be mentioned. These hardening accelerators can be used by mixing 1 type or 2 or more types suitably.

In this embodiment, the content of the curing accelerator is not particularly limited, but from the viewpoint of obtaining a high glass transition temperature, the range of 0.001 to 5 parts by mass is preferable, and 0.01 to 3 parts by mass per 100 parts by mass of the resin solid content in the resin composition. The range of parts by mass is more preferable. Moreover, when using two or more types of hardening accelerators together, it is preferable that these total amount satisfy the said range.

The resin composition of the present embodiment may contain various other high molecular compounds and/or flame retardant compounds. The polymer compound and the flame-retardant compound are not particularly limited as long as they are generally used.

Examples of the polymer compound include various thermosetting resins and thermoplastic resins, oligomers and elastomers thereof, in addition to the thermosetting resin (A). Specifically, polyimide, polyamideimide, polystyrene, polyolefin, styrene-butadiene rubber (SBR), isoprene rubber (IR), butadiene rubber (BR), acrylonitrile butadiene rubber (NBR), polyurethane, polypropylene, (Meth)acrylic oligomers, (meth)acrylic polymers, and silicone resins. From the viewpoint of compatibility, acrylonitrile butadiene rubber is preferred.

As a specific example of the flame retardant compound, as other than (B) spherical filler and (C) short glass fiber, a phosphorus-containing compound (for example, a phosphate ester, a melamine phosphate, a phosphorus-containing epoxy resin), a nitrogen-containing compound (for example, , Melamine, benzoguanamine), oxazine ring-containing compounds, and silicone compounds. These polymeric compounds and/or flame-retardant compounds may be used alone or in combination of two or more as appropriate.

The resin composition of this embodiment may contain various additives according to various purposes. Specific examples of the additives include ultraviolet absorbers, antioxidants, photopolymerization initiators, optical brighteners, photosensitizers, dyes, pigments, thickeners, lubricants, defoaming agents, dispersants, leveling agents and brightening agents. These additives can be used alone or in combination of two or more as appropriate.

(Resin composition and its manufacturing method)

The resin composition of the present embodiment is prepared by mixing (A) a thermosetting resin, (B) a spherical filler, (C) short glass fibers having an average fiber length of 10 to 300 µm, and other components as necessary. Moreover, the resin composition may be in the form of a solution in which these components are dissolved in an organic solvent, if necessary. The solution of such a resin composition can be preferably used as a varnish when manufacturing the copper foil with the insulating resin layer of the present embodiment described later. The organic solvent is not particularly limited as long as each component can be preferably dissolved or dispersed, and further exhibits the effect of the resin composition of the present embodiment. Specific examples of the organic solvent include alcohols (e.g., methanol, ethanol and propanol), ketones (e.g., acetone, methyl ethyl ketone and methyl isobutyl ketone), amides (e.g., dimethylacetamide And dimethylformamide) and aromatic hydrocarbons (eg, toluene and xylene). These organic solvents can be used alone or in combination of two or more as appropriate.

(Insulating resin layer made of resin composition)

The insulating resin layer of this embodiment is obtained from the resin composition of this embodiment. The thickness of the insulating resin layer is not particularly limited, but in terms of smoothness and orientation of the short glass fibers, the range of 3 to 50 µm is preferable, and from the viewpoint of further obtaining good moldability, it is more than 6 to 45 µm. It is preferable, and it is more preferable that it is 8-40 micrometers from the point which the adhesiveness of favorable copper foil and an insulating resin layer is obtained further.

(Method of manufacturing copper foil with insulating resin layer formed)

In this embodiment, the method of manufacturing the copper foil in which the insulating resin layer of this embodiment was formed by laminating an insulating resin layer made of a resin composition on copper foil is not specifically limited. As a manufacturing method, for example, a solution (varnish) in which a resin composition is dissolved or dispersed in an organic solvent is applied to the surface of copper foil, dried under heating and/or reduced pressure, and the solvent is removed to solidify the resin composition, The method of forming an insulating resin layer is mentioned.

The drying conditions are not particularly limited, but drying is performed so that the content ratio of the organic solvent to the insulating resin layer is usually 10 parts by mass or less, preferably 5 parts by mass or less, based on 100 parts by mass of the insulating resin layer. The conditions for achieving drying are also different depending on the amount of organic solvent in the varnish. For example, in the case of a varnish containing 30 to 60 parts by mass of an organic solvent with respect to 100 parts by mass of the varnish, heating conditions of 50 to 160°C You just need to dry it for 3 to 10 minutes.

[Printed wiring board]

The printed wiring board of this embodiment can be obtained by using the copper foil with the insulating resin layer of this embodiment as a build-up material with respect to the metal foil-clad laminated board in which the insulating resin layer called the core base material is completely cured. In this embodiment, a copper foil having a thin insulating resin layer in which an insulating resin layer having high adhesion and high toughness is laminated on a copper foil having high rigidity and excellent adhesion to the insulating resin layer is used, so that thick support A thin printed wiring board can be manufactured without using a substrate (carrier substrate). The printed wiring board obtained by using the copper foil with the insulating resin layer of the present embodiment is thin, has high-density fine wiring, and has few appearance defects.

On the surface of the metal foil-clad laminated plate, a conductor circuit is formed by a conductor layer obtained by plating after peeling off the metal foil and/or metal foil of a commonly used metal foil-clad laminate. In addition, the base material of the metal foil-clad laminate is not particularly limited, but is mainly a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, and a thermosetting polyphenylene ether substrate.

In the present embodiment, the build-up is to laminate the insulating resin layer in the copper foil on which the insulating resin layer of the present embodiment is formed with respect to the metal foil and/or the conductor layer on the surface of the metal foil-clad laminate.

Usually, when an insulating resin layer (resin composition layer) is laminated on a metal foil-clad laminate using an adhesive film or the like as a build-up material, an insulating resin layer is provided on one side or both sides of the resulting printed wiring board. A conductor layer is formed with respect to this insulating resin layer, but since the surface roughness of the insulating resin layer after curing is low, irregularities are formed by roughening treatment including a desmear treatment, and then, electroless plating and/or Alternatively, a conductor layer is formed using electrolytic plating. However, on the surface of the insulating resin layer subjected to the roughening treatment, inorganic substances such as glass fibers in the resin composition are exposed (protruded), and the surface is rough. In addition, there is also a problem that large depressions are formed in the insulating resin layer by the inorganic material falling out of the insulating resin layer. Therefore, it is difficult to form high-density fine wiring on the surface of such an insulating resin layer. Further, when forming through holes such as via holes and/or through holes, inorganic substances such as glass fibers are liable to remain, and there is also a problem of adversely affecting reliability.

However, when the copper foil on which the insulating resin layer of the present embodiment is formed is laminated on a metal foil-clad laminate as a build-up material, copper foil is provided on one or both surfaces of the resulting printed wiring board. Since the circuit pattern can be directly formed on the copper foil without performing the plating treatment, a high-density fine wiring can be formed. Moreover, even if plating treatment is performed after etching the copper foil at the time of manufacturing a printed wiring board or a substrate for mounting a semiconductor element, since the surface of the copper foil is transferred to the insulating resin layer, the adhesion between the insulating resin layer and the plating is improved.

In the manufacture of a printed wiring board, if necessary, hole processing, such as a via hole and/or a through hole, is performed in order to electrically connect each conductor layer. When this hole processing is performed, after that, a roughening treatment including a desmear treatment is performed. In this embodiment, since the surface of the printed wiring board is protected with copper foil having excellent adhesion to the insulating resin layer, the roughening treatment Even if is carried out, the surface of the printed wiring board does not become rough.

Hole processing is usually performed using a mechanical drill, a carbon dioxide laser, a UV laser, a YAG laser, or the like. In this embodiment, since the surface of the printed wiring board is protected with copper foil, the energy of these drills or lasers can be increased. Therefore, according to the present embodiment, as shown in the schematic diagram of FIG. 1, in the hole processing, inorganic substances such as glass fibers exposed from the surface of the hole can be preferably removed.

In addition, the roughening treatment is usually composed of a swelling step, a surface roughening and smear dissolution step, and a neutralization step.

The swelling process is performed by swelling the surface of the insulating resin layer using a swelling agent. The swelling agent is not particularly limited as long as it can swell the surface of the insulating resin layer to such an extent that the wettability of the surface of the insulating resin layer is improved and oxidative decomposition is promoted in the following surface roughening and smear dissolution step. As an example, an alkali solution, a surfactant solution, etc. are mentioned.

The surface roughening and smear dissolution process are performed using an oxidizing agent. Examples of the oxidizing agent include an alkaline permanganate solution and the like, and preferable specific examples include an aqueous potassium permanganate solution, an aqueous sodium permanganate solution, and the like. Such oxidizing agent treatment is called wet desmear.In addition to the wet desmear, it may be performed by appropriately combining other known roughening treatments such as plasma treatment or UV treatment dry desmear, mechanical polishing by buffing, and sand blasting. do.

The neutralization step is to neutralize the oxidizing agent used in the previous step with a reducing agent. Examples of the reducing agent include an amine reducing agent, and preferable specific examples include an acidic aqueous solution such as an aqueous hydroxylamine sulfate solution, an aqueous ethylenediamine tetraacetic acid solution, and an aqueous nitrilotriacetic acid solution.

In this embodiment, after forming the via hole and/or through hole, or after desmearing the inside of the via hole and/or through hole, it is preferable to perform metal plating treatment to electrically connect each conductor layer. In the present embodiment, even if the metal plating treatment is performed, the adhesion between the insulating resin layer and the metal plating is improved because the copper foil surface is transferred to the insulating resin layer.

The method of metal plating treatment is not particularly limited, and a method of metal plating treatment in the production of a conventional multilayer printed wiring board can be appropriately used. The method of the metal plating treatment and the kind of the chemical liquid used for plating are not particularly limited, and a metal plating treatment method and a chemical liquid in the production of a conventional multilayer printed wiring board can be appropriately used. The chemical liquid used in the metal plating treatment may be a commercial product.

The metal plating treatment method is not particularly limited, and for example, treatment with a degreasing liquid, treatment with a soft etching liquid, acid washing, treatment with a pre-dip liquid, treatment with a catalytic liquid, a treatment with an accelerator liquid, Treatment with a chemical copper liquid, acid washing, and treatment in which an electric current is passed by immersing in a copper sulfate liquid are mentioned.

In addition, in the case of build-up using a copper foil with an insulating resin layer in a semi-cured state, a printed wiring board can be obtained by generally performing heat treatment or the like on the insulating resin layer in a semi-cured state to completely cure. In this embodiment, on the obtained printed wiring board, the copper foil with the insulating resin layer of the other embodiment may be further laminated.

The lamination method in the build-up method is not particularly limited, but a vacuum pressurized laminator can be preferably used. In this case, the copper foil on which the insulating resin layer of the present embodiment is formed may be laminated through an elastic body such as rubber. The lamination condition is not particularly limited as long as it is a condition used for lamination of a conventional printed wiring board. For example, a temperature of 70 to 140°C, a contact pressure in the range of 1 to 11 kgf/cm 2, and a contact pressure of 20 hPa or less It is carried out under reduced pressure of the atmosphere. After the lamination process, the laminated adhesive film may be smoothed by hot pressing with a metal plate. The lamination process and the smoothing process can be continuously performed by a commercially available vacuum pressurized laminator. After the lamination process or after the smoothing process, you may have a thermosetting process. By using the thermosetting process, the insulating resin layer can be completely cured. The thermosetting conditions differ depending on the kind of components contained in the resin composition, and the like, but usually the curing temperature is 170 to 190°C and the curing time is 15 to 60 minutes.

As a method of forming a circuit pattern with respect to the copper foil on one side or both sides of the printed wiring board of the present embodiment, a semi-additive method, a full additive method, a subtractive method, and the like may be mentioned. Among them, the semi-additive method is preferable in terms of forming a fine wiring pattern.

As an example of a method of forming a circuit pattern by a semi-additive method, electrolytic plating is selectively performed using a plating resist (pattern plating), then the plating resist is peeled off, and an appropriate amount of the entire is etched to form a wiring pattern. There is a technique. In the circuit pattern formation by the semi-additive method, electroless plating and electrolytic plating are combined and performed. In that case, drying is preferably performed after electroless plating and after electrolytic plating, respectively. Drying after electroless is not particularly limited, for example, it is preferably carried out at 80 to 180°C for 10 to 120 minutes, and drying after electrolytic plating is not particularly limited, but, for example, at 130 to 220°C It is preferable to carry out for 10 to 120 minutes. As plating, copper plating is preferable.

As an example of a method of forming a circuit pattern by a subtractive method, a method of forming a wiring pattern by selectively removing a conductor layer using an etching resist is exemplified. Specifically, it can be implemented as follows, for example. A dry film resist (RD-1225 (trade name) manufactured by Hitachi Chemical Co., Ltd.) is laminated (laminated) on the entire surface of the copper foil at a temperature of 110 ± 10°C and a pressure of 0.50 ± 0.02 MPa. Then, it exposes along the circuit pattern and performs masking. Thereafter, the dry film resist is developed with a 1% sodium carbonate aqueous solution, and finally the dry film resist is peeled off with an amine-based resist stripper. Thereby, circuit patterning can be formed on the copper foil.

In this embodiment, an insulating resin layer and/or a conductor layer may be further laminated on the printed wiring board to obtain a multilayer printed wiring board. You may have a circuit board in the inner layer of a multilayer printed wiring board. The insulating resin layer of the copper foil on which the insulating resin layer of the present embodiment is formed constitutes one of the insulating resin layer and the conductor layer of the multilayer printed wiring board.

The method of lamination is not particularly limited, and a method generally used for lamination molding of a conventional printed wiring board can be used. As a lamination method, a multistage press, a multistage vacuum press, a laminator, a vacuum laminator, an autoclave molding machine, etc. are mentioned, for example. The temperature at the time of lamination is not particularly limited, for example, 100 to 300° C., and the pressure is not particularly limited, but, for example, 0.1 to 100 kgf/cm 2 (about 9.8 kPa to about 9.8 MPa), heating Although time is not specifically limited, For example, it selects suitably in the range of 30 seconds-5 hours, and implements. Further, if necessary, for example, post-curing may be performed in a temperature range of 150 to 300°C to adjust the degree of curing.

[Substrate for mounting semiconductor devices]

The semiconductor element mounting substrate is manufactured by laminating a copper foil with an insulating resin layer of the present embodiment on a metal foil-clad laminate, for example, and masking and patterning the copper foil on the surface or one side of the obtained laminate. For masking and patterning, known masking and patterning performed in the manufacture of printed wiring boards can be used, and although not particularly limited, it is preferable to form a circuit pattern by the above-described subtractive method. The circuit pattern may be formed only on one side of the laminate or may be formed on both sides.

The substrate for mounting a semiconductor element obtained by using the copper foil with an insulating resin layer of the present embodiment is thin, has high-density fine wiring, and has few appearance defects.

Example

Examples of the present embodiment will be described, but the present embodiment is not limited by these examples at all.

[One. Evaluation of copper foil]

(1) arithmetic mean roughness

The copper foil surface was photographed with a shape measuring microscope (laser microscope, VK-X210 (trade name) manufactured by Keyence Corporation) at an objective lens magnification of 150 times (magnification on a 15 type monitor: 3000 times). Subsequently, the height distribution on a straight line having a length of 90 µm selected at random from among the captured images was obtained by image processing, and the arithmetic mean roughness Ra was calculated.

[2. Evaluation of metal foil clad laminate]

(1) Formability

The copper foil was removed by etching the metal foil-clad laminate to be described later. The surface of the obtained resin substrate (insulating resin layer) was visually checked, and when cracks or voids, remarkable unevenness or deflection of the resin were observed due to molding, it was set as "C", and otherwise, "A".

(2) Transferability test

The copper foil was removed by etching the metal foil-clad laminate to be described later. After making the obtained resin substrate (insulating resin layer) into a square shape of 100 mm x 50 mm, it was put into a peeling line (a peeling part of an eminent-type developing etching peeling line, a pressure of 0.1 MPa, manufactured by Tokyo Chemical Industry Co., Ltd.) , The presence or absence of damage to the resin substrate was confirmed by washing with water.

When the resin substrate was damaged and the missing portion was 1% or more of the mass before the injection, it was evaluated as "C", and when less than 1%, it was evaluated as "A".

In addition, in Comparative Examples 3 and 4, the polyethylene terephthalate film of the obtained adhesive film was peeled off, and a 12 µm-thick copper foil (3EC-III (brand name) manufactured by Mitsui Metal Mining Co., Ltd.) was placed on both sides. It arrange|positioned so that it may contact, and the metal foil-clad laminated board was obtained by performing molding for 120 minutes at a pressure of 30 kgf/cm<2> and a temperature of 220 degreeC. About the obtained metal foil clad laminated board, the said moldability and conveyance test were performed.

(3) Laser processing test

The thickness of the copper was changed from 12 µm to 5 µm by half etching treatment (Clean Etch (registered trademark) CPE-770 (trade name) manufactured by Mitsubishi Gas Chemical Co., Ltd.) to the metal foil-clad laminate to be described later, and then laser pretreatment (Atotech Japan Corporation BONDFilm (registered trademark) LDD101 (brand name)) was carried out. The pre-treated laminate was subjected to a hole drilling process with an opening diameter of φ60 µm using a carbon dioxide gas laser processing machine (ML605GTW3(H)-5200U (trade name) manufactured by Mitsubishi Electric Corporation, 1.1 mm mask) for a printed circuit board. I did. Thereafter, after the cross section of the opening was polished, the surface of the opening was observed using a SEM (scanning electron microscope, VE-7800S manufactured by Keyence Corporation (trade name)) at 500 times magnification. From the obtained SEM image, a glass fiber in which the glass fiber protrudes from the cross section of the opening was found, the distance between the base and the tip of the portion where the glass fiber protrudes was measured five times, and the average value was calculated. When the average value was 5 μm or less, it was evaluated as “A”, and when it was larger than 5 μm, it was evaluated as “C”.

In addition, in Comparative Examples 3 and 4, a carbon dioxide gas laser processing machine for printed circuit boards (ML605GTW3(H)-5200U (brand name) manufactured by Mitsubishi Electric Co., Ltd., 1.1 mm of mask) was used for the obtained laminate substrate (non-smear treatment). Then, a blind via hole (perforation) having an opening diameter of φ80 µm was performed. After that, in the same manner as in the laser processing test, the average value of the distance between the base and the tip of the portion where the glass fiber protrudes was calculated and evaluated.

(4) Appearance after desmear treatment

The laminate substrates described in Comparative Examples 3 and 4 were subjected to a desmear treatment. Desmear treatment was swelled by immersing in a swelling liquid for desmear (PTH-B103 (trade name) manufactured by Okuno Pharmaceutical Co., Ltd.) at 65°C for 5 minutes, and then swelling, and then desmear treatment liquid (PTH1200 (brand name) and PTH1200NA ( (Trade name), Okuno Pharmaceutical Co., Ltd.), immersed at 80°C for 8 minutes, and finally, immersed in a neutralizing solution for desmear (Okuno Pharmaceutical Co., Ltd. PTH-B303 (brand name)) at 45° C. for 5 minutes It was carried out. Thereafter, the surface condition of the laminate substrate after the desmear treatment is checked, and in the case of a uniform surface shape, it is indicated as ``A'', when an uneven surface shape, dropping of glass fibers are seen, or glass fibers are exposed on the surface. E was evaluated as "C".

(5) Peel strength measurement

The insulating resin layer applied to the copper foil with a bar coater and the copper foil according to the test method (5.7 peel strength) described in JIS C6481 using the test piece (30 mm × 150 mm × 0.8 mm thickness) of the metal foil-clad laminate described later The peeling strength (peel strength) of was measured three times, and the average value (kN/m) was calculated|required.

In the same way, using the laminate substrate subjected to the plating treatment described in Comparative Examples 3 and 4, the peel strength (peel strength) of the copper plating layer and the insulating resin layer was measured three times, and the average value (kN/m) was calculated. I did.

Peel strength was evaluated based on the following criteria by the obtained average value.

A: 0.6 kN/m or more

B: 0.4 kN/m or more and less than 0.6 kN/m

C: less than 0.4 kN/m

[3. Production of copper foil with resin composition and insulating resin layer formed]

(Synthesis of α-naphthol aralkyl type cyanate ester compound)

A reactor equipped with a thermometer, stirrer, dropping funnel and reflux condenser was previously cooled to 0 to 5°C with brine, and thereto, 7.47 g (0.122 mol) of cyanochloric acid, 9.75 g (0.0935 mol) of 35% hydrochloric acid, water 76 Ml and 44 ml of methylene chloride were injected. Subsequently, the temperature in this reactor is maintained at -5 to +5°C and the pH is 1 or less, and while stirring, α-naphthol aralkyl represented by the following formula (4) (SN485 (trade name) manufactured by Shinnittetsu Chemical Co., Ltd.), OH group equivalent: 214 g/eq.Softening point: 86°C) 20 g (0.0935 mol) and 14.16 g (0.14 mol) of triethylamine dissolved in 92 ml of methylene chloride were added to a dropping funnel for 1 hour. It was dripped over. After completion of the dropwise addition, 4.72 g (0.047 mol) of triethylamine was added dropwise over 15 minutes.

[Formula 4]

(In formula (4), n ⁴ was an average value and was in the range of 3-4.)

After completion of the dropwise addition, after stirring at the same temperature for 15 minutes, the reaction solution was separated and the organic layer was separated and collected. After washing the obtained organic layer twice with 100 ml of water, methylene chloride was distilled off under reduced pressure with an evaporator, and finally concentrated to dryness at 80° C. for 1 hour to obtain α-naphthol aralkyl represented by the following formula (5). 23.5 g of type cyanate ester compounds were obtained.

[Formula 5]

(In formula (5), n ⁵ was the range of 3-4 as an average value.)

[Example 1]

50 parts by mass of the α-naphthol aralkyl type cyanate ester compound represented by the above formula (5), bis(3-ethyl-5-methyl-4-maleimidephenyl)methane (KI Chemical Co., Ltd. BMI-70 ( Trade name)) 10 parts by mass and 40 parts by mass of a polyoxynaphthylene-type epoxy resin (EXA-7311 (trade name) manufactured by DIC Corporation, epoxy equivalent: 277 g/eq.) were mixed and dissolved in methyl ethyl ketone. Next, 3 parts by mass of a wetting dispersant (Disperbyk (registered trademark)-161 manufactured by Vicchemy Japan Co., Ltd.) was added to this solution, and spherical fused silica (average particle diameter: 0.4 to 0.6 µm, manufactured by Admatex Co., Ltd. SC2050-MB (brand name)) 250 parts by mass, zinc octylate 0.02 parts by mass, acrylonitrile butadiene rubber (N220S (brand name) manufactured by JSR Corporation) 5 parts by mass, milled fiber (Central Glass Fiber Co., Ltd.) ) Produced EFDE50-31 (trade name), average fiber length: 50 µm, fiber diameter: 6 µm) 21 parts by mass were mixed to prepare a varnish. The obtained varnish was diluted with methyl ethyl ketone, and a copper foil having a thickness of 350 mm × 250 mm × 12 μm by a bar coater (arithmetic mean roughness (Ra): 1.0 to 1.5 μm, 3EC-III manufactured by Mitsui Metal Mining Co., Ltd. It applied on the mat surface side of (trade name)), and heated and dried at 130°C for 5 minutes to obtain a copper foil with an insulating resin layer having an insulating resin layer having a thickness of 40 µm.

A 12 µm-thick copper foil (3EC-III (brand name) manufactured by Mitsui Metal Mining Co., Ltd.) was placed so that the mat surface was in contact with the surface side of the insulating resin layer of the obtained insulating resin layer-formed copper foil, and a pressure of 30 kgf/cm 2, A metal foil-clad laminate was obtained by performing molding at a temperature of 220°C for 120 minutes. It evaluated about the obtained metal foil-clad laminated board, and the result was shown in Table 1. Moreover, the SEM image of the surface of the opening part was shown in FIG.

[Example 2]

The same as in Example 1, except that the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 μm, fiber diameter: 6 μm) was changed from 21 parts by mass to 63 parts by mass. Thus, a copper foil with an insulating resin layer having a thickness of 40 µm in the insulating resin layer was obtained. Then, it carried out similarly to Example 1, and obtained the metal foil-clad laminated board. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Example 3]

The same as in Example 1, except that the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 μm, fiber diameter: 6 μm) was changed from 21 parts by mass to 100 parts by mass. Thus, a copper foil with an insulating resin layer having a thickness of 40 µm in the insulating resin layer was obtained. Then, it carried out similarly to Example 1, and obtained the metal foil-clad laminated board. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Example 4]

The same as in Example 1 except that the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 μm, fiber diameter: 6 μm) was changed from 21 parts by mass to 300 parts by mass. Thus, a copper foil with an insulating resin layer having a thickness of 40 µm in the insulating resin layer was obtained. Then, it carried out similarly to Example 1, and obtained the metal foil-clad laminated board. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Example 5]

In the same manner as in Example 1 except that the thickness of the insulating resin layer was changed from 40 µm to 15 µm, a copper foil with an insulating resin layer having a thickness of 15 µm was obtained. Then, it carried out similarly to Example 1, and obtained the metal foil-clad laminated board. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

Moreover, since the thickness of the insulating resin layer was thin and the metal foil-clad laminate could not be etched, the conveyance test was not performed.

[Example 6]

The varnish obtained in Example 1 was diluted with methyl ethyl ketone, and a copper foil having a thickness of 350 mm × 250 mm × 12 μm with a bar coater (arithmetic mean roughness (Ra): 0.5 μm, 3EC- manufactured by Mitsui Metal Mining Co., Ltd.) M2S-VLP (brand name)) was applied to the mat surface side and heated and dried at 130° C. for 5 minutes to obtain a copper foil with an insulating resin layer having a thickness of 40 μm. Thereafter, in the same manner as in Example 1, a metal foil-clad laminate was obtained using a 12 µm-thick copper foil (3EC-III (brand name) manufactured by Mitsui Metal Mining Co., Ltd.). The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Example 7]

In place of the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., the average fiber length: 50 μm, fiber diameter: 6 µm), EFH30-01 manufactured by Central Glass Fiber Co., Ltd. ), average fiber length: 30 µm, fiber diameter: 11 µm), in the same manner as in Example 1, to obtain a copper foil with an insulating resin layer having an insulating resin layer having a thickness of 40 µm. Then, it carried out similarly to Example 1, and obtained the metal foil-clad laminated board. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Example 8]

In place of the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., the average fiber length: 50 µm, fiber diameter: 6 µm), EFH150-31 manufactured by Central Glass Fiber Co., Ltd. ), average fiber length: 150 µm, fiber diameter: 11 µm), in the same manner as in Example 1, to obtain a copper foil with an insulating resin layer having an insulating resin layer having a thickness of 40 µm. Then, it carried out similarly to Example 1, and obtained the metal foil-clad laminated board. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Comparative Example 1]

In the same manner as in Example 1, except that the milled fiber (EFDE50-31 (brand name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 µm, fiber diameter: 6 µm) was not mixed, the insulating resin layer was A copper foil with an insulating resin layer having a thickness of 40 µm was obtained. The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1. In addition, in the evaluation of laser workability, in Comparative Example 1, the milled fiber was not blended, so that the glass fiber protruding from the end face of the opening was not confirmed.

[Comparative Example 2]

The same as in Example 1, except that the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 μm, fiber diameter: 6 μm) was changed from 21 parts by mass to 500 parts by mass. Thus, a varnish was prepared. The obtained varnish was diluted with methyl ethyl ketone, and an attempt was made to apply it to a polyethylene terephthalate film (thickness: 38 µm) with a bar coater, but it could not be applied and an adhesive film could not be obtained.

[Comparative Example 3]

The same as in Example 1, except that the milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 μm, fiber diameter: 6 μm) was changed from 21 parts by mass to 63 parts by mass. Thus, a varnish was prepared. This varnish is diluted with methyl ethyl ketone, applied to a polyethylene terephthalate film (thickness: 38 μm) with a bar coater, and heated and dried at 130° C. for 5 minutes, whereby the layer of the resin composition has a thickness of 40 μm. Got it. A conveyance test was performed about the obtained adhesive film, and the result was shown in Table 1.

Next, both sides of the copper clad laminate (CCL (registered trademark) manufactured by Mitsubishi Gas Chemical Co., Ltd.-HL832NSF (brand name), the thickness of the insulating resin layer: 0.1 mm, the thickness of the copper foil: 12 μm) A roughening treatment was performed with CZ-8100 (brand name) to obtain a roughened product of a copper clad laminate. The adhesive film obtained above was placed on both sides of the roughened product of the copper clad laminate so that the layer made of the resin composition and the copper foil were in contact, and a batch-type vacuum pressurized laminator (CVP-600 (brand name) manufactured by Nichigo Morton Co., Ltd.) It laminated using, and obtained the laminated body. Lamination was carried out by pressing in a vacuum at a temperature of 120° C. and a pressure of 8 kgf/cm 2. The polyethylene terephthalate film was peeled off from both surfaces of the obtained laminate. Thereafter, a layer made of a resin composition was cured under curing conditions at a temperature of 80° C. for 30 minutes and then at a temperature of 180° C. for 30 minutes, forming an insulating resin layer, and a laminate having insulating resin layers on both sides of the copper clad laminate The substrate was obtained. The obtained laminate substrate was subjected to a laser processing test, and the results are shown in Table 1. Further, an SEM image of the surface of the opening is shown in FIG. 3.

A desmear treatment was performed on the laminate substrate on which the hole drilling was performed by laser processing, and the appearance after the treatment was confirmed. The results are shown in Table 1. Since there was no copper foil on both sides, it was confirmed that the protrusion of the glass fiber was large and the surface was rough.

The obtained laminate substrate after the desmear treatment was subjected to copper plating to form a copper plating layer having a thickness of 18 µm. The peel strength was measured using the laminate substrate subjected to the plating treatment. The results are shown in Table 1.

[Comparative Example 4]

Except that milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 µm, fiber diameter: 6 µm) was not blended, it was carried out in the same manner as in Comparative Example 3 to form a resin composition. An adhesive film having a layer thickness of 40 µm, a laminate substrate having an insulating resin layer on both sides of a copper clad laminate, a laminate substrate subjected to a hole drilling process by laser processing, and a laminate substrate after desmear treatment were obtained. For these, evaluation was performed in the same manner as in Comparative Example 3, and the results are shown in Table 1. In addition, in the evaluation of the laser workability and the appearance after the desmear treatment, in Comparative Example 4, the milled fiber was not blended, so that the glass fiber protruding from the end face of the opening was not recognized, and the surface shape was also uniform.

[Comparative Example 5]

12 µm thick copper foil on both sides of the prepreg (GHPL-830NSF (trade name) manufactured by Mitsubishi Gas Chemical Co., Ltd., thickness of the insulating resin layer: 40 µm) (3EC-III (trade name) manufactured by Mitsui Metal Mining Co., Ltd.) ), and molding at a pressure of 30 kgf/cm 2 and a temperature of 220°C for 120 minutes to obtain a metal foil-clad laminate. About the obtained metal foil-clad laminated board, the conveyance test and the laser processing test were evaluated, and the results are shown in Table 1.

[Comparative Example 6]

Milled fiber (EFDE50-31 (trade name) manufactured by Central Glass Fiber Co., Ltd., average fiber length: 50 µm, fiber diameter: 6 µm) was changed from 21 parts by mass to 63 parts by mass, and spherical fused silica (Admatex ( Note) A varnish was prepared in the same manner as in Example 1, except that the manufactured SC2050MB (brand name)) was not mixed. In the same manner as in Example 1, the obtained varnish was diluted with methyl ethyl ketone, and a copper foil having a thickness of 350 mm × 250 mm × 12 μm (3EC-III (brand name) manufactured by Mitsui Metal Mining Co., Ltd.) It was applied to the mat side. Thereafter, by heating and drying at 130°C for 5 minutes, an attempt was made to produce a copper foil with an insulating resin layer, but the insulating resin layer could not be molded, and a copper foil with an insulating resin layer could not be produced.

[Comparative Example 7]

The varnish obtained in Example 1 was diluted with methyl ethyl ketone, and a copper foil having a thickness of 350 mm × 250 mm × 12 µm with a bar coater (arithmetic mean roughness (Ra): 0.04 µm, GHT5-HA manufactured by JX Metal Co., Ltd.) (Brand name)), and heat-dried at 130°C for 5 minutes to obtain a copper foil with an insulating resin layer having a thickness of 40 µm. Thereafter, in the same manner as in Example 1, a metal foil-clad laminate was obtained using a 12 µm-thick copper foil (3EC-III (brand name) manufactured by Mitsui Metal Mining Co., Ltd.). The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

[Comparative Example 8]

The varnish obtained in Example 1 was diluted with methyl ethyl ketone, and a copper foil having a thickness of 350 mm × 250 mm × 70 μm by a bar coater (arithmetic mean roughness (Ra): 4 μm, GY manufactured by Furukawa Circuit Foil Taiwan (FCFT)) -MP (brand name)) was applied to the mat surface side and heated and dried at 130°C for 5 minutes to obtain a copper foil with an insulating resin layer having a thickness of 40 µm. Thereafter, in the same manner as in Example 1, a metal foil-clad laminate was obtained using a 12 µm-thick copper foil (3EC-III (brand name) manufactured by Mitsui Metal Mining Co., Ltd.). The obtained metal foil-clad laminate was evaluated and the results are shown in Table 1.

This application is based on the Japanese patent application (Japanese Patent Application No. 2017-239467) for which it applied on December 14, 2017, The content is taken in here as a reference.

Industrial availability

Advantageous Effects of Invention According to the present invention, it is possible to preferably obtain a thin printed wiring board and a semiconductor element mounting substrate in which high-density fine wiring is formed and good through holes are formed.

10: Printed wiring board in which an insulating resin layer is laminated on a copper clad laminate (before drilling)
11: Printed wiring board in which an insulating resin layer is laminated on a copper clad laminate (after drilling)
20: Printed wiring board in which the copper foil with the insulating resin layer of this embodiment is laminated on a metal foil-clad laminate (before drilling)
21: Printed wiring board in which the copper foil on which the insulating resin layer of this embodiment was formed is laminated on a metal foil-clad laminate (after drilling)
30: insulating resin layer
31: copper foil
32: inorganic substances such as glass fiber
40: the part where the glass fiber protrudes

Claims (9)

With copper foil,
Including an insulating resin layer laminated on the copper foil,
The arithmetic mean roughness (Ra) of the surface of the copper foil in contact with the insulating resin layer is 0.05 to 2 µm,
The copper foil with an insulating resin layer, wherein the insulating resin layer is made of a resin composition containing (A) a thermosetting resin, (B) a spherical filler, and (C) short glass fibers having an average fiber length of 10 to 300 µm. The method of claim 1,
The copper foil on which the insulating resin layer is formed, wherein the insulating resin layer has a thickness of 3 to 50 µm. The method according to claim 1 or 2,
The copper foil with an insulating resin layer, wherein the copper foil has a thickness of 1 to 18 µm. The method according to any one of claims 1 to 3,
The copper foil with an insulating resin layer having a fiber diameter of 1 to 15 µm of the short glass fibers. The method according to any one of claims 1 to 4,
The copper foil with an insulating resin layer, wherein the content of the short glass fibers is 5 to 450 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition. The method according to any one of claims 1 to 5,
The short glass fiber is a milled fiber, a copper foil with an insulating resin layer formed. The method according to any one of claims 1 to 6,
The copper foil with an insulating resin layer in which the content of the spherical filler is 50 to 500 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition. The method according to any one of claims 1 to 7,
The thermosetting resin is from the group consisting of an epoxy resin, a cyanate ester compound, a maleimide compound, a phenol resin, a thermosetting modified polyphenylene ether resin, a benzoxazine compound, an organic group modified silicone compound, and a compound having a polymerizable unsaturated group. Copper foil with an insulating resin layer containing at least one selected type. The method according to any one of claims 1 to 8,
Copper foil with an insulating resin layer for use as a build-up material for printed wiring boards or semiconductor device mounting substrates.

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