JP2001131309A - High-dielectric constant b-stage sheet and printed wiring board using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a B-stage sheet suitable for use in high-dielectric constant capacitors, and to obtain a high-density printed wiring board by using the above sheet. SOLUTION: This high-dielectric constant B-stage sheet is obtained by the following process: (a) a total of 100 pts.wt. of a polyfunctional cyanic ester monomer and a prepolymer thereof is compounded with (b) 50-10,000 pts.wt. of an epoxy resin liquid at room temperature, and 100 pts.wt. of the (a+b) component is compounded with 0.005-10 pts.wt. of a thermosetting catalyst to prepare a resin composition; subsequently, a solventless resin component essentially comprising the above resin composition is compounded with an electrically insulating inorganic filler >=500 in dielectric constant at room temperature so that the filler accounts for 80-90 wt.% of the final sheet. The other objective high-dielectric constant printed wiring board excellent in heat resistance, electrical properties after moisture absorption, adhesion to copper foil, etc., can be obtained by using the B-stage sheet described above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a stage sheet and a printed wiring board using the copper-clad board as a capacitor. In particular, printed wiring boards obtained by drilling with a carbon dioxide gas laser are mainly used as new high-density small-sized printed wiring boards for mounting small and light-weight semiconductor plastic packages.

[0002]

2. Description of the Related Art In recent years, high-density multilayer printed wiring boards have been used in electronic devices that are becoming smaller, thinner and lighter. When a layer having a high relative dielectric constant is provided in the inner and outer layers of the printed wiring board and this layer is used as a capacitor, the mounting density can be improved. To provide a high relative dielectric constant layer on the inner layer, outer layer or substrate of a multilayer board, see JP-A-55-57212, JP-A-61-136281, and JP-A-61-136281.
No. 167547, JP-A-62-19451, epoxy resin as shown in Japanese Patent Publication No. 5-415, modified polyphenylene oxide resin, etc., blended a high dielectric constant inorganic powder such as barium titanate, This was impregnated into a fiber base material such as a glass cloth, and a plurality of prepregs obtained by drying were laminated, a copper foil was arranged on the outermost layer, and laminated to form a high dielectric constant copper-clad laminate. . This glass cloth base copper-clad laminate has a thickness of 50 μm,
μm or more, and a thinner insulating layer could not be produced any more. In addition, inorganic fillers have high specific gravity,
When dispersed in a varnish, there is no case of adding a large amount because of sedimentation. Further, it is difficult to lower the content of the resin due to the inclusion of the glass cloth substrate. In the examples of the above publications, only those having a relative dielectric constant of about 10 to 20 were obtained. Therefore, a capacitor having a large capacitance could not be formed, and it could not be used as a laminate having a capacitor function.

On the other hand, even when a resin composition comprising a general thermosetting resin and a high relative dielectric constant inorganic powder is used, when a large amount of an inorganic filler is used, the obtained copper-clad laminate is brittle,
Furthermore, it has high heat resistance and has a relative dielectric constant of 50 or more, more preferably 100
The above copper clad board could not be made. JP Hei 9-
As shown in No. 12742, without using a glass cloth substrate, a high dielectric constant film obtained by mixing a thermosetting resin and an inorganic powder having a dielectric constant of 50 or more, into a film shape For this reason, the viscosity of the resin is high, and the upper limit of the amount of the inorganic filler to be added is about 60% by weight. Therefore, the relative permittivity of the obtained copper-clad laminate was as small as about 10, and a relative permittivity of 50 or more was not obtained.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems. The thickness of the insulating layer is as thin as, for example, 50 μm or less, and the relative dielectric constant is as large as 50 or more. Provided is a B-stage sheet having a high relative dielectric constant, which can be processed in the same manner as a conductive resin prepreg, and a printed wiring board using the B-stage sheet as a capacitor.
In particular, it is suitable for providing a high-density printed wiring board in which small-diameter holes are formed by a carbon dioxide laser.

[0005]

According to the present invention, an epoxy resin (b) 5 which is liquid at room temperature is added to 100 parts by weight of a polyfunctional cyanate ester monomer and the cyanate ester prepolymer (a).
0 to 10,000 parts by weight, and 0.005 to 10 parts by weight of a thermosetting catalyst based on 100 parts by weight of the total amount of the cyanate ester monomer, the cyanate ester prepolymer and the epoxy resin (a + b). Is a solvent-free resin component containing a resin composition containing as an essential component, a dielectric constant of 500 at room temperature.
A high relative permittivity B stage sheet is provided, wherein the above-mentioned insulating inorganic filler is blended to be 80 to 99% by weight. Further, the present invention provides a copper-coated sheet in which a copper foil is adhered to one surface of the high relative permittivity B stage sheet. The present invention further provides a high-density printed wiring board using the high-permittivity B-stage sheet.

According to the present invention, an insulating sheet having a thickness of 50 μm or less or a sheet with copper foil can be used, and a printed wiring board can be used to obtain a high heat resistance, a high relative dielectric constant, It is possible to obtain a printed wiring board having excellent small hole diameter by a carbon dioxide laser, excellent adhesion to a copper foil, and excellent reliability. Of course, a sheet having a thickness of 50 μm or more can be created. The copper-clad laminate obtained using this sheet can be perforated by a mechanical drill, but is preferably drilled by a laser because it has a large amount of inorganic filler and large drill wear. It is preferable to use a carbon dioxide laser from the viewpoint of processing speed and the like. There is no particular limitation on the method of making a hole with a carbon dioxide laser, but through-holes and / or via holes can be easily formed by placing an auxiliary material on a copper-clad laminate and directly irradiating a high-energy carbon dioxide laser. it can. When a through hole and / or a via hole is formed, a copper foil burr remains around the hole. This can be removed by mechanical polishing or the like, but since burrs cannot be completely removed, preferably, in the case of a thick copper foil having a thickness of 9 to 12 μm, the copper foil on the copper foil surface layer is removed in the thickness direction. Remaining thickness 2
Copper foil burrs generated around the hole until the thickness becomes 7 μm are removed by etching with a chemical solution, copper plating is performed, and a circuit is formed on the front and back surfaces to obtain a printed wiring board. When a multilayer laminated board is used, a copper surface treatment, a prepreg and a copper foil are arranged on at least one side of the printed wiring board, and a multilayer copper-clad board obtained by lamination molding is used. Form holes and / or via holes that penetrate the front and back so as to connect the foil, etch away a part of the copper foil on the front and back with a chemical solution, through-hole plating, via-hole plating, and after forming the front and back circuits, necessary To form a printed wiring board.

For drilling, generally known drilling methods such as an excimer laser, a YAG laser, a carbon dioxide laser, and a mechanical drill can be used. However, it is preferable to use a carbon dioxide gas laser in terms of workability, drilling speed, hole reliability, and the like. The through holes and / or via holes having a hole diameter of 25 to 180 μm are generally formed by laser. Excimer laser and YAG laser are preferable for the holes having a diameter of 25 μm or more and less than 80 μm, and the holes having a diameter of 80 μm or more and 180 μm or less are subjected to a metal oxide treatment or a chemical treatment on the copper foil surface, or a melting point of 90 μm or less.
A coating containing 3 to 97% by volume of one or more of metal compound powder, carbon powder, or metal powder having a binding energy of 300 kJ / mol or more at 0 ° C. or more, or A sheet formed by coating on a thermoplastic film is preferably disposed on a copper foil surface with a total thickness of 30 to 200 μm. Then, a carbon dioxide laser having an output of preferably 20 to 60 mJ / pulse is directly irradiated with a carbon dioxide laser to form a through hole for a through hole. After drilling, the surface of the copper foil can be mechanically polished to remove burrs. However, in order to completely remove burrs, preferably, both surfaces of the copper foil are etched in a plane, and the original metal foil is partially etched away in the thickness direction, so that the copper overhanging the hole is removed. It is also preferable to remove the foil burrs by etching, and because the copper foil becomes thinner, defects such as short-circuits and cut patterns in the circuit formation of the fine wires of the front and back copper foils obtained by plating up by subsequent metal plating. A high-density printed wiring board can be produced without the occurrence of the problem. When the front and back copper foils are thinned by etching, it is preferable that the resin layer adhering to the surface of the inner copper foil exposed inside the hole is removed by etching, preferably after at least gas phase treatment. The inside of the hole can be filled with 50% by volume or more by copper plating. When the thickness of the copper foil is as thin as 3 to 7 μm from the beginning, an auxiliary material is attached to the front and back surfaces of the copper foil, and a carbon dioxide gas laser is directly irradiated therefrom to form through holes and / or via holes. , Leaving the auxiliary material as it is, spraying or sucking the etchant, dissolving and removing the surface layer and inner layer copper foil burrs, removing the surface auxiliary material layer, performing desmearing if necessary, Attach plating. The processing speed was remarkably faster than when drilling, and a product with good productivity and excellent economy was obtained. In the case where a through hole having a hole diameter of more than 180 μm is formed, an excimer laser, a YAG laser, or a mechanical drill is used. Preferably, a mechanical drill is used.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyfunctional cyanate ester monomer, said cyanate prepolymer (a) 1
50 to 1 part by weight of a liquid epoxy resin (b) 50 to 1 at room temperature
000 parts by weight, and a resin composition containing 0.005 to 10 parts by weight of a thermosetting catalyst with respect to 100 parts by weight of the (a + b) component. 80 to 99 insulative inorganic fillers having a ratio of 500 or more at room temperature
Provided is a high-permittivity B-stage sheet having a relative permittivity of a cured product of 50% or more by weight. The present invention further provides a printed wiring board using the high relative dielectric constant B stage sheet as a capacitor. If a large amount of the inorganic filler is added, particularly 80% by weight or more, disadvantages such as a decrease in the adhesive strength of the copper foil occur. For this reason, a B-stage sheet with a copper foil to which a large amount of an inorganic filler is added has not been developed in the conventional proposal. In the present invention, the relative dielectric constant of the inorganic filler at room temperature is particularly high in order to produce a copper-clad laminate having a relative dielectric constant of 50 or more, and a copper foil adhesive strength and a printed wiring board using the same. 500 or more, preferably 1,000 or more are used. As the resin, a liquid resin which can be easily formed into a sheet, and a polyfunctional cyanate compound for maintaining the properties are used. After blending these, they are uniformly mixed and dispersed to form a sheet or adhered to one side of a copper foil to form a copper-clad sheet.

The polyfunctional cyanate compound used in the present invention is a compound having two or more cyanato groups in a molecule. Specific examples include 1,3- or 1,4-dicyanatobenzene, 1,3,5-tricyanatobenzene, 1,3
-, 1,4-, 1,6-, 1,8-, 2,6- or 2,7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4-dicyanatobiphenyl, bis ( 4-dicyanatophenyl) methane, 2,2-
Bis (4-cyanatophenyl) propane, 2,2-bis (3,5-dibromo-4-cyanatophenyl) propane, bis (4-cyanatophenyl) ether, bis (4-cyanatophenyl) thioether, bis (4-Cyanatophenyl) sulfone, tris
(4-cyanatophenyl) phosphite, tris (4-cyanatophenyl) phosphate, and cyanates obtained by reacting novolak with cyanogen halide.

In addition to these, Japanese Patent Publication Nos. 41-1928 and 43-1846
8, polyfunctional cyanate compounds described in JP-A-44-4791, JP-A-45-11712, JP-A-46-41112, JP-A-47-26853 and JP-A-51-63149 can also be used. Further, a prepolymer having a molecular weight of 400 to 6,000 and having a triazine ring formed by trimerization of a cyanato group of these polyfunctional cyanate compounds is used. This prepolymer is obtained by polymerizing the above-mentioned polyfunctional cyanate ester monomer with a catalyst such as an acid such as a mineral acid or a Lewis acid; a base such as a tertiary amine such as sodium alcoholate; or a salt such as sodium carbonate. It can be obtained by: The prepolymer also contains some unreacted monomers and is in the form of a mixture of the monomer and the prepolymer, and such a raw material is suitably used for the purpose of the present invention. Generally, it is used after being dissolved in a soluble organic solvent.

As the epoxy resin which is liquid at room temperature, a generally known epoxy resin can be used. Specifically, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, diglycidylated polyether polyol, epoxidized acid anhydride, alicyclic epoxy resin, etc. alone or in combination of two or more Used. The amount used is a polyfunctional cyanate ester monomer, the cyanate ester prepolymer 100
50 to 10,000 parts by weight, preferably 10 parts by weight
0 to 500 parts by weight.

Various additives can be added to the thermosetting resin composition of the present invention, if desired, as long as the inherent properties of the composition are not impaired. These additives include polymerizable double bond-containing monomers such as unsaturated polyesters and prepolymers thereof; polybutadiene, epoxidized butadiene, maleated butadiene, butadiene-
Low molecular weight liquid to high molecular weight elastic rubbers such as acrylonitrile copolymer, polychloroprene, butadiene-styrene copolymer, polyisoprene, butyl rubber, fluororubber, natural rubber; polyethylene, polypropylene, polybutene, poly-4-methyl Penten, polystyrene, AS
Resin, ABS resin, MBS resin, styrene-isoprene rubber,
Polyethylene-propylene copolymer, 4-fluoroethylene-
6-fluorinated ethylene copolymers; high molecular weight prepolymers or oligomers such as polycarbonate, polyphenylene ether, polysulfone, polyester, and polyphenylene sulfide; and polyurethane are exemplified and used as appropriate. In addition, other known inorganic and organic fillers,
Various additives such as dyes, pigments, thickeners, lubricants, defoamers, dispersants, leveling agents, photosensitizers, flame retardants, brighteners, polymerization inhibitors, and thixotropic agents may be used as desired. They are used in an appropriate combination. If necessary, the compound having a reactive group is appropriately blended with a curing agent and a catalyst.

The thermosetting resin composition of the present invention can be cured by heating itself, but has a low curing rate and is inferior in workability and economic efficiency. Can be used. The amount used is based on 100 parts by weight of the total of the polyfunctional cyanate ester component and the epoxy resin component.
It is 0.005 to 10 parts by weight, preferably 0.01 to 5 parts by weight.

The inorganic filler of the present invention has a relative dielectric constant of 500 or more, and is particularly preferably a titanate-based ceramic. Specifically, barium titanate-based ceramics,
Examples include strontium titanate-based ceramics, lead titanate-based ceramics, magnesium titanate-based ceramics, calcium titanate-based ceramics, bismuth titanate-based ceramics, and lead zirconate-based ceramics. In terms of composition, these are components alone or systems containing other small amounts of additives, and the crystal structure of the main component is maintained. These are used alone or in combination of two or more. A single material or a material obtained by sintering two or more kinds and then pulverizing is also used. The amount used is 80 to 99% by weight, preferably 85 to 95% by weight of the whole.

The method for uniformly kneading the components of the present invention is as follows:
Generally known methods can be used. For example, after the respective components are blended, they are kneaded with a three-roll mill at room temperature or under heating, or generally known materials such as a ball mill and a raikai machine are used. Using this, a sheet is formed under pressure by a roll. Alternatively, it is extruded and adhered to one side of a copper foil to form a B stage sheet with a copper foil. The thickness is set to a predetermined thickness, preferably 50 μm or less. It is also possible to form a viscous solution by adding a part of a solvent, apply a predetermined thickness to the release film or copper foil surface by knife coating or the like, and dry the sheet. The copper foil used in the present invention is not particularly limited, but an electrolytic copper foil having a thickness of 3 to 18 μm is preferably used.
The lamination molding conditions for the copper clad board used in the present invention are generally a temperature of 150 to 250 ° C., a pressure of 5 to 50 kgf / cm ² , and a time of 1 to 5 hours. Further, it is preferable to carry out lamination molding under vacuum.

When drilling via holes and / or through holes in the copper-clad plate obtained by the present invention, those having a hole diameter exceeding 180 μm are preferably drilled with a mechanical drill. In addition, hole diameter 25μm
The holes having a diameter of 180 μm or less are preferably formed with a laser. Holes having a hole diameter of 25 μm or more and less than 80 μm are preferably formed by an excimer laser or a YAG laser. Also, 80
In the hole of μm or more and 180 mμ or less, a metal oxide treatment or a chemical treatment is applied to the copper foil surface, or a metal compound powder having a melting point of 900 ° C. or more and a binding energy of 300 kJ / mol or more, carbon powder,
Alternatively, it is preferable to perform drilling by directly irradiating a carbon dioxide gas laser after placing an auxiliary material made of a resin composition containing one or more metal powders. of course,
Other common drilling methods can also be used.

The auxiliary material used in the present invention has a melting point of 90.
As the metal compound having a binding energy of 300 kJ / mol or more at 0 ° C. or more, generally known metal compounds can be used. Specifically, as the oxide, titania such as titanium oxide, magnesia such as magnesium oxide, iron oxide such as iron oxide, nickel oxide such as nickel oxide, manganese dioxide, zinc oxide such as zinc oxide , Silicon oxide, aluminum oxide, rare earth oxides, cobalt oxides such as cobalt oxide, tin oxides such as tin oxide, and tungsten oxides such as tungsten oxide. Examples of the non-oxide include generally known ones such as silicon carbide, tungsten carbide, boron nitride, silicon nitride, titanium nitride, aluminum nitride, barium sulfate, and rare earth oxysulfide. In addition, carbon can also be used. Further, various glasses which are a mixture of the metal oxide powders may be mentioned. In addition, carbon powders may be mentioned, and further, simple substances such as silver, aluminum, bismuth, cobalt, copper, iron, magnesium, manganese, molybdenum, nickel, palladium, antimony, silicon, tin, titanium, vanadium, tungsten, zinc and the like. An alloy metal powder is used. These may be used alone or in combination of two or more. The average particle size is
Although not particularly limited, 1 μm or less is preferable.

Since the molecules are dissociated or melted and scattered by the irradiation of the carbon dioxide laser, the metal adheres to the hole wall or the like and does not adversely affect the semiconductor chip and the hole wall adhesion. preferable. Since Na, K, Cl ions and the like particularly adversely affect the reliability of the semiconductor, those containing these components are not suitable. The compounding amount is 3 to 97% by volume, preferably 5 to 95% by volume, and is preferably mixed with the water-soluble resin and uniformly dispersed. The water-soluble resin of the auxiliary material is not particularly limited, but a resin that does not peel off when kneaded and applied to the surface of the copper foil and dried or when formed into a sheet is selected. For example, generally known materials such as polyvinyl alcohol, polyester, polyether and starch are used.

The method for preparing the metal compound powder, the carbon powder, or the composition comprising the metal powder and the resin is not particularly limited, but is kneaded at a high temperature without a solvent in a kneader or the like, and extruded into a sheet on a thermoplastic film. A method of dissolving a water-soluble resin in water, adding the powder to the mixture, stirring and mixing the mixture uniformly, and applying the mixture to a thermoplastic film as a paint, followed by drying to form a film. And other generally known methods. The thickness is not particularly limited, but is generally used in a total thickness of 30 to 200 μm.

Alternatively, a hole can be formed in the same manner after a metal oxide treatment is applied to the surface of the copper foil. The treatment is not particularly limited, for example, black copper oxide treatment,
MM processing (Mac Darmid) can be used. Further, as the chemical solution treatment, for example, CZ treatment (MEC Corporation) or the like can be preferably used. However, it is preferable to use the above auxiliary material from the viewpoint of the hole shape and the like. On the back side, it is preferable to use a backup sheet in which a water-soluble resin is adhered on a metal plate on the back side in order to avoid damage to the table of the carbon dioxide laser when the through-hole is formed. The auxiliary material is applied as a coating film on the copper foil surface or is applied on a thermoplastic film to form a sheet. When heating the sheet to the copper foil surface, laminating under pressure, the auxiliary material, the backup sheet together with the applied resin layer toward the copper foil surface, with a roll, the temperature is generally 40 ~ 150 ℃, preferably 60 ~ 120 ℃ , The linear pressure is generally 0.
Lamination is performed under a pressure of 5 to 20 kg, preferably 1 to 10 kg, and the resin layer is melted and brought into close contact with the copper foil surface. The selection of the temperature depends on the melting point of the water-soluble resin used, and also depends on the linear pressure and the laminating speed. In general, lamination is performed at a temperature higher by 5 to 20 ° C. than the melting point of the water-soluble resin. or,
In the case of close contact at room temperature, the surface of the applied resin layer of 3 μm or less is moistened with water before lamination to dissolve a small amount of the water-soluble resin, and is laminated under the same pressure. The method of moistening with water is not particularly limited, but, for example, a method in which water is continuously applied to the coating resin surface by a roll, and thereafter, a method of continuously laminating the surface of the copper-clad laminate, the water is sprayed. A method of continuously spraying the coating film surface and then continuously laminating the surface of the copper-clad laminate may be used.

A carbon dioxide laser, preferably with an output of 20-60
When holes are formed by irradiation with mJ / pulse, burrs occur around the holes. This is not a particular problem in a double-sided copper-clad laminate with thin copper foil, and the resin remaining on the copper foil surface is removed by gas phase or liquid phase treatment, and the inside of the hole is directly plated with copper. More than 50% of the inside of the hole is plated with copper, and the surface layer is also plated at the same time so that the thickness of the copper foil can be reduced to 18 μm or less. However, preferably, the etching liquid is sprayed or sucked through the hole to dissolve and remove the overhanging copper foil burr, and at the same time, the thickness of the surface copper foil is 2 to 7 μm, preferably 3 to 5 μm. Etching and copper plating. In this case, etching with a chemical solution is more preferable than mechanical polishing in terms of removing burrs from holes, dimensional change due to polishing, and the like. The method of etching and removing copper burrs generated in the holes according to the present invention is not particularly limited. For example, Japanese Patent Application Laid-Open Nos. 02-22887, 02-22896, 02-25089, and 02-2
5090, 02-59337, 02-60189, 02-166789, 03-25
995, 03-60183, 03-94491, 04-199592, 04-263
No. 488 discloses a method of dissolving and removing a metal surface with a chemical (referred to as a SUEP method). The etching rate is generally 0.02 to 1.0 μm / sec.

The carbon dioxide laser is in the infrared wavelength range.
Wavelengths of 9.3 to 10.6 μm are commonly used. The output is preferably made of copper foil at 20 to 60 mJ / pulse to make holes. Excimer lasers generally have wavelengths of 248 to 308 nm, and YAG lasers have wavelengths of 351 to 355 nm, but are not limited thereto. The processing speed of the carbon dioxide laser is remarkably fast and economical. When drilling through holes, a method of irradiating energy selected from 20 to 60 mJ / pulse from the beginning to the end, a method of changing the energy in the middle, and the like can be used. When removing the surface copper foil, by selecting a higher energy, the number of irradiation shots is small and the efficiency is good. When processing the intermediate resin layer, high output is not necessarily required, and it can be appropriately selected depending on the base material and the resin. For example, the output can be selected from 10 to 35 mJ / pulse. Of course, high-power processing can be performed until the end. The processing conditions can be changed with or without the inner layer copper foil inside the hole.

In most cases, a resin layer of about 1 μm remains in the inner layer copper foil inside the hole processed by the carbon dioxide laser. Further, when a hole is drilled with a mechanical drill, smear may remain. By removing this resin layer, the connection reliability between the further copper plating and the copper in the inner and outer layers is improved. In order to remove the resin layer, generally known treatments such as desmear treatment can be performed.However, when the liquid does not reach the inside of the small-diameter hole, the removal residue of the resin layer remaining on the copper foil surface of the inner layer occurs. Connection failure with copper plating may occur. Therefore, more preferably, the inside of the hole is first treated in the gas phase to completely remove the residual layer of the resin, and then the inside of the hole is wet-treated, preferably by using ultrasonic waves. As the gas phase treatment, generally known treatments can be used, and examples thereof include a plasma treatment and a low-pressure ultraviolet treatment. Plasma is
Molecules are partially excited by a high-frequency power source and ionized low-temperature plasma is used. For this, high-speed processing using ion bombardment and gentle processing using radical species are generally used, and reactive gases and inert gases are used as processing gases. As the reactive gas, oxygen is mainly used, and the surface is chemically treated. As the inert gas, an argon gas is mainly used. Using this argon gas or the like, physical surface treatment is performed. Physical treatment uses ion bombardment to clean the surface. Low ultraviolet light is ultraviolet light having a short wavelength range, and has a wavelength of 184.
The resin layer is decomposed and removed by irradiating a short wavelength region having a peak at 9 nm and 253.7 nm. After that, since the resin surface is often made hydrophobic, it is preferable to perform the wet treatment using ultrasonic waves in combination with the copper plating, particularly in the case of small-diameter holes. The wetting treatment is not particularly limited, but includes, for example, an aqueous solution of potassium permanganate, an aqueous solution for soft etching, and the like.

The inside of the hole is necessarily 50% by volume with copper plating
Electrical continuity can be obtained without filling. Preferably 50
It is good to fill by volume%, more preferably 90 volume% or more. However, if the inside of the hole is filled with a longer plating time, the workability is poor, and a method using a pulse plating additive (manufactured by Nippon Rironal Co., Ltd.) suitable for filling the hole is preferably used.

[0025]

The present invention will be specifically described below with reference to examples and comparative examples. Unless otherwise specified, “parts” indicates parts by weight.

Examples 1 to 7 2,2-bis (4-cyanatophenyl) propane monomer (component
1,000 parts of A-1) were melted at 150 ° C. and reacted with stirring for 4 hours to obtain a prepolymer having an average molecular weight of 1,900 (component A-2). Bisphenol A type epoxy resin (product name: Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd., component B-1), bisphenol F type epoxy resin (product name: EXA830LVP, Dainippon Ink) Chemical Industry Co., Ltd., component B-2), novolak type epoxy resin (trade name: DEN431, manufactured by Dow Chemical Co., Ltd., component B-3), and iron acetylacetone (component C-
1), 2-ethyl-4-methylimidazole (component C-2), and an epoxysilane coupling agent (trade name: A-187, manufactured by Nippon Yunika Co., Ltd., component D-1) as an additive Varnish. Barium titanate ceramics (relative dielectric constant at 1 MHz at room temperature: 2010, specific surface area 0.41 m ² / g, component E-1) as inorganic filler, bismuth titanate ceramics (relative dielectric constant at room temperature) Rate: 733, specific surface area 0.52
m ² / g, component E-2), barium titanate 90% -calcium stannate 10% ceramic (relative permittivity at room temperature: 502)
0, specific surface area 0.45m ² / g, calcined and pulverized product, component E-3)
And blended as shown in Tables 1 and 2 using a raikai machine.
Kneaded uniformly for minutes. This is extruded to a thickness of 50 μm on one side of a 12 μm electrolytic copper foil to form a sheet, or a small amount of methyl ethyl ketone is added to the copper foil, dried and the solvent is blown off to adhere. It was created. Place 12μm electrolytic copper foil on this resin surface, 200 ℃, 20
Laminate molding was performed for 2 hours under a vacuum of kgf / cm ² and 30 mmHg or less to obtain a double-sided copper-clad board. Table 2 shows the evaluation results.

On the other hand, 800 parts of black copper oxide powder (average particle diameter: 0.8 μm) as a metal oxide powder was added to a varnish prepared by dissolving polyvinyl alcohol powder in water, and uniformly stirred and mixed.
This was coated on one side of a 50 μm-thick polyethylene terephthalate film so as to have a thickness of 30 μm.
After drying for 0 minutes, an auxiliary material F having a metal compound powder content of 45% by volume was prepared. On the double-sided board, placed so that the resin side faces the copper foil side, laminated at 100 ℃, the hole diameter 1
44 shots of 00μm holes are directly irradiated with 4 shots of 30mJ / pulse in a 6mm square at the center within a 20mm square with an output of 30mJ / pulse, and this is treated as one block, and a through hole for through-hole of 70 blocks is made and SUEP treatment is performed. Then, the surface copper foil was etched until it became 3 μm, and burrs around the holes were also dissolved and removed. Copper plating is applied to 13μm, and the inside of the hole is plated with copper.
Filled 5% by volume. Use the existing method for the front and back circuits (line /
(Space = 50/50 μm), lands for solder balls, etc. were formed, covered with a plating resist except for at least the semiconductor chip mounting portion, pad portions, and solder ball pad portions, and nickel and gold plating were applied to create printed wiring boards .
On top of this, a flip chip of 10 mm square was mounted. The evaluation results are shown in Tables 3 and 4.

Comparative Examples 1-3 Epoxy resin solid at room temperature (trade name: Epicoat 5045)
2,000 parts, dicyandiamide 70 parts, 2-ethylimidazo
2 parts of methyl ethyl ketone and dimethylformamide
Dissolve in a mixed solvent, stir and mix to uniformly disperse and
(This solid was designated as component A-3). Titanic acid
Barium (particle size 0.5-5μm, specific surface area 0.89m ^Two/ g, dielectric constant
Rate 2010, E-4) as shown in Tables 1 and 2.
And knead it homogeneously to obtain a thickness of 50 μm and a weight of 48 g / m.^Twoof
Impregnated and dried glass woven fabric, glass content 35% by weight
Created a B-stage prepreg. Dry resin is acceptable
There was no flexibility, and the resin peeled off when bent. On both sides
Place 12μm electrolytic copper foil, 190 ° C, 20kgf / cm^Two, 30mmHg
Laminate for 2 hours under the following vacuum to make a double-sided copper-clad laminate
Done. Hole diameter 200 with a mechanical drill on this copper clad laminate
A through hole of μm was formed. Normal copper without SUEP treatment
Plating was deposited at 10 μm. Using this, print distribution
A wire plate was created. Table 5 shows the evaluation results.

Comparative Example 4 Titanium dioxide powder (with a relative dielectric constant of 30,
Surface area 1.26 m ² / g, component E-5) so as to be 90% by weight, mix well with a raikai machine, and apply to a copper foil to a thickness of 40 μm. It dried and the copper foil with resin of B stage was created. 12μm thick on this resin surface
Was placed under the same press conditions as in the comparative example, but the resin flow was poor and voids were observed. Table 5 shows the evaluation results.

[0030]

[Table 1]
Unit: parts by weight

[0031]

[Table 2]
Unit: parts by weight

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

[Table 5]

<Measurement method> 1) Void after lamination molding The laminated and formed copper foil was removed by etching, and voids were visually observed. 2) Adhesive strength of copper foil Measured according to JIS C6481. 3) PCT (pressure cooker; 121 ℃ ・ 203kPa, 2hrs.)
After the heat resistance of the solder after the treatment, it was immersed in the solder at 260 ° C. for 30 sec. 4) Create a board without holes in the same way as in the circuit pattern break, short circuit, example, comparative example,
After a comb-shaped pattern of line / space = 50/50 μm was formed, 200 patterns after etching were visually observed with a magnifying glass, and the total of the cut and short-circuited patterns was indicated in the molecule. 5) Glass transition temperature Measured by the DMA method. 6) Through-hole heat cycle test A land diameter of 250 μm is created for each through-hole, 900 holes are connected alternately on the front and back, and one cycle consists of 260 ° C, solder, immersion for 30 seconds → room temperature for 5 minutes, up to 150 cycles The maximum value of the rate of change of the resistance value was shown. 7) Insulation resistance value after pressure cooker treatment A comb-shaped pattern was created between terminals (line / space = 50/50 μm), and the prepregs used were placed on each of them, and the laminate was molded at 121 ° C. After processing at 203kPa for a predetermined time, post-processing at 25 ° C and 60% RH for 2 hours,
0 VDC was applied to measure the insulation resistance between the terminals. 8) Migration resistance The test piece of 6) was applied at 85 ° C and 85% RH at 50 VDC to measure the insulation resistance between terminals. 9) Relative permittivity It was measured by an LCR meter and calculated by calculation.

[0036]

According to the present invention, a polyfunctional cyanate ester monomer, the cyanate ester prepolymer (a) 1
50 parts by weight of the epoxy resin (b) liquid at room temperature
After sintering to a solvent-free resin component, a resin composition comprising 10,000 parts by weight and a resin composition in which 0.005 to 10 parts by weight of a thermosetting catalyst is added to 100 parts by weight of the (a + b) component. A high relative dielectric constant B stage sheet obtained by uniformly mixing 80 to 99% by weight, preferably 85 to 95% by weight of an insulating inorganic filler having a relative dielectric constant of 500 or more. This stage sheet is made of a copper-clad laminate and a printed wiring board is excellent in heat resistance, adhesiveness with copper foil, electrical insulation after moisture absorption, and a dielectric constant of 50 or more is obtained. A useful capacitor was created. In addition, by using an auxiliary material on a copper-clad laminate, it is possible to directly pierce a small-diameter hole by irradiating a high-energy carbon dioxide laser, thereby obtaining a high-density printed wiring board. Was.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08L 79/04 C08L 79/04 Z 5E317 H05K 1/03 610 H05K 1/03 610L 5E346 610R 1/16 1 / 16 D 3/42 640 3/42 640B 3/46 3/46 TQ F term (reference) 4E351 AA03 BB01 BB03 BB30 BB35 BB49 CC06 CC22 DD04 DD06 DD19 DD41 DD58 EE27 GG01 GG06 4F071 AA42 AA58 AB18 AC07 AC12 AE03AE BA09 BB06 BB13 BC01 BC17 4J002 CD00W CD02W CD05W CD06W CD10W CM02X DE078 DE098 DE138 EE047 ET006 EU117 EU186 EV046 EV216 EW046 EW066 FA088 FD14X FD146 FD207 GQ01 GQ05 4J036 AA01 AB10 FB08 FA03 DC03 AG03 FB02 FB19 GA17 JA05 JA08 4J043 PA02 PC136 QC14 RA47 SA13 SB01 TA56 TB01 UA121 UA131 UA261 UB011 UB021 UB1 21 UB281 UB301 UB381 VA021 VA041 ZA42 ZB50 5E317 AA24 BB02 BB12 BB13 BB15 CC31 CC52 CD01 CD15 CD18 CD21 CD25 CD27 CD32 GG03 GG12 5E346 AA05 AA06 AA12 AA15 AA23 AA32 AA33 AA43 BB01 GG01 BB01 BB01 GG01

Claims (8)

[Claims] 1. A polyfunctional cyanate ester monomer, 100 parts by weight of the cyanate ester prepolymer (a), and 50 to 10,000 parts by weight of a liquid epoxy resin (b) at room temperature are blended. Total amount of monomer, cyanate ester prepolymer and epoxy resin (a + b) 10
A solvent-free resin component containing a resin composition containing 0.005 to 10 parts by weight of a thermosetting catalyst per 0 parts by weight as an essential component,
80 insulative inorganic filler with relative dielectric constant of 500 or more at room temperature
A high-permittivity B-stage sheet, wherein the B-stage sheet is blended in an amount of about 99% by weight. 2. An insulating inorganic filler comprising a barium titanate-based ceramic, a lead titanate-based ceramic, a calcium titanate-based ceramic, a magnesium titanate-based ceramic, a bismuth titanate-based ceramic, a strontium titanate-based ceramic, and zirconic acid 2. A high dielectric constant B according to claim 1, wherein the insulating inorganic filler contains at least one selected from the group consisting of lead-based ceramics, or at least one of these is pulverized after sintering. Stage sheet. 3. The insulating inorganic filler has a particle size of 3 to 50 μm,
3. The high relative dielectric constant B stage sheet according to claim 1, wherein the specific surface area is 0.35 to 0.60 m ² / g. 4. The B-stage sheet has a relative dielectric constant after curing.
4. The high-permittivity B-stage sheet according to claim 1, wherein the B-stage sheet has 50 or more. 5. The B-stage sheet according to claim 1, wherein the B-stage sheet is a sheet with copper having a copper foil adhered to one side thereof. 6. A high-density printed wiring board using the B-stage sheet according to claim 1 as a capacitor. 7. The printed wiring board according to claim 6, which is directly irradiated with a carbon dioxide gas laser by pulse oscillation of a carbon dioxide gas laser having a sufficient carbon dioxide laser energy to remove the copper foil, thereby forming a double-sided copper-clad board. When forming via holes and / or through-holes including copper foil, one side of the copper foil is subjected to metal oxide treatment or chemical treatment, or as a drilling auxiliary material,
At least 900 ° C or higher melting point and 300 binding energy
1 of metal compound powder, carbon powder or metal powder of kJ / mol or more
After arranging a resin composition layer containing 3 to 97% by volume of one or more kinds of components, a double-sided copper-clad board obtained by forming a via hole and / or a through hole by directly irradiating a carbon dioxide laser is provided. A high-density printed wiring board characterized by using. 8. After forming a via hole and / or a through-hole, a part of the surface copper foil is dissolved with a chemical solution to a residual copper foil thickness of 2 to 7 μm before copper plating of the hole is performed. 8. The high-density printed wiring board according to claim 7, wherein the copper foil burrs protruding in the holes are also dissolved and removed.