JP2000068641A - Manufacturing method of printed wiring board - Google Patents

Abstract

(57) [Problem] To produce a printed wiring board having excellent through-hole reliability by a dry system manufacturing method. SOLUTION: A through hole is formed on one side of a metal plate.
A frusto-conical protrusion or a conductive adhesive is attached. A frusto-conical protrusion is formed, an insulating layer slightly thinner than the protrusion is formed on the protrusion side, and a metal foil is placed outside the protrusion, and both sides are laminated under heat and pressure. Using a metal foil-clad laminate, circuit formation and precious metal plating are performed to obtain a printed wiring board. [Effect] Through-hole connection reliability, heat resistance after moisture absorption,
It was possible to manufacture a printed wiring board having excellent electrical insulation properties and resistance to migration after pressure cooker.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a printed wiring board for a novel dry system. The obtained printed wiring board is mainly used as a package for mounting and using a semiconductor chip.

[0002]

2. Description of the Related Art Conventionally, a double-sided metal foil-clad laminate used for a printed wiring board is made by impregnating a base material such as a glass woven fabric with a thermosetting resin composition and drying the prepreg to form a B stage. It is made by laminating under heat and pressure. Holes for through-holes are made at predetermined positions in this double-sided metal foil-clad laminate, and metal plating is applied to conduct the front and back circuits. Metal attached to the through hole has a thickness of 15 to 25μ
m, and poor adhesion of the plating may cause peeling and cutting of the plating due to stress at the time of heating and cooling, causing a problem in reliability. In addition, the steps are complicated, and those having a large plate thickness and a small hole diameter have difficulty in plating through holes, and have a problem in reliability.

[0003]

SUMMARY OF THE INVENTION The present invention provides a printed wiring board in which the above problems are improved.

[0004]

According to the present invention, a truncated cone-shaped projection is formed on at least one side of a metal plate at a position where a through-hole is to be formed. Or to form a truncated cone-shaped protrusion with a conductive adhesive by a method such as etching after attaching a conductive adhesive before forming a truncated cone-shaped protrusion,
A semi-cured prepreg, resin sheet, resin-coated metal foil, or coated resin layer that is slightly thinner than the height of the entire projection is placed on the projection side, and a metal foil is placed outside the resin layer where no metal foil is attached Then, a double-sided metal foil-clad laminate is prepared by laminating and molding under heat and pressure, and then a circuit is formed on this double-sided metal-foil-clad laminate, and a printed wiring board prepared by performing noble metal plating is provided. I do. The present invention further provides a printed wiring board which preferably uses a polyfunctional cyanate resin composition as a resin layer. According to the present invention, the printed wiring board having the above-described configuration has excellent heat resistance after moisture absorption, moisture resistance, electrical insulation after pressure cooker treatment, and migration resistance, and requires desmear treatment and through-hole plating. Therefore, a small-diameter through hole with excellent reliability can be manufactured by a dry system, and a novel printed wiring board with improved workability is provided.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The printed wiring board of the present invention has a truncated conical projection formed on one surface of a metal plate as a through hole or the like of the printed wiring board, and is subjected to a surface chemical treatment if necessary. Create a metal plate with a conductive adhesive on it, and place a semi-cured prepreg, resin sheet, resin-coated metal foil, or coated resin layer that is slightly thinner than the height of the projection on the projection side. It is manufactured by placing a metal foil on the outside of the resin layer without the mark, laminating and molding under heat and pressure, forming a circuit, and applying noble metal plating.

[0006] A known printed wiring board having a through hole is formed by drilling the through hole with a mechanical drill or the like and performing metal plating. If the diameter of the through hole is smaller than the thickness of the plate, problems such as poor adhesion of metal plating and lack of reliability occur. The present invention first forms a truncated cone-shaped protrusion at a position where a metal plate as a metal core is formed in advance by a known etching method or the like, for forming a front and back circuit conduction, a semiconductor chip heat dissipation through hole, and the like. A conductive adhesive such as solder paste or silver paste is attached to the trapezoid before or after etching, and a resin sheet or a base material is impregnated with resin on the protrusion side and dried to obtain a semi-cured prepreg. And, if necessary,
The metal foil is arranged and laminated under heat, pressure and vacuum to form a double-sided metal foil-clad laminate.

The surface of the metal plate on which the frustoconical projections are formed is subjected to a surface treatment for improving adhesiveness and electric insulation such as oxidation treatment, formation of fine irregularities, and formation of a film, as necessary, by a known method.

A projection with a conductive adhesive is formed on the truncated cone, and after lamination molding, is adhered to an inner layer circuit or the like to improve connection reliability. As the conductive adhesive, a generally known conductive adhesive is used. Specific examples include solder paste, lead-free solder, silver paste, and copper paste.

The lamination molding conditions vary depending on the resin used and are not particularly limited, but are generally heated at 100 to 300 ° C., preferably 150 to 250 ° C. Pressure, 3~50kgf / cm ^2,
Preferably, it is 5 to 35 kgf / cm ² , and the time is 1 to 5 hours.

After the front and back circuits are formed, noble metal plating is formed on at least the surface of the wire bonding pad to complete the printed wiring board. In this case, a portion that does not require noble metal plating is covered with a plating resist in advance. Or, after plating, if necessary, a known thermosetting resin composition, or a photoselective thermosetting resin composition, at least a semiconductor chip mounting portion, a bonding pad, a coating on a surface other than the solder ball bonding pad on the opposite surface. Form.

Although the metal plate used in the present invention is not particularly limited, a metal plate having a high elastic modulus, a high thermal conductivity and a thickness of 70 to 300 μm is preferable. Specifically, pure copper, oxygen-free copper, and alloys with Fe, Sn, P, Cr, Zr. Zn or the like containing 95% by weight or more of copper are preferably used. Further, a metal plate or the like in which the surface of the alloy is plated with copper may be used.

The height of the truncated conical projection of the metal plate of the present invention is not particularly limited, but is preferably 50 to 150 μm. Also, the thickness of the insulating layer such as prepreg, resin sheet, metal foil with resin, coating resin, etc., is slightly lower than the height of the truncated conical protrusion or the conductive adhesive attached metal truncated conical protrusion, preferably 5 to 15 μm lower. After the lamination molding, the protrusions and the surface metal foil are connected with a conductive adhesive. The portion corresponding to the truncated conical projection is formed by a generally known processing method such as an etching method. The thickness of the remaining metal plate is 10
7070 μm. It is preferable to make the thickness as much as possible the same as the thickness of the metal foil on the opposite surface disposed on the prepreg, from the viewpoint of preventing warpage.

According to the manufacturing method of the present invention, it is not necessary to form a clearance hole or a slit hole for a through-hole for conducting a front-to-back circuit through metal plating, and a printed wiring board can be formed by a dry system. it can.

As the resin of the thermosetting resin composition used in the present invention, generally known thermosetting resins are used. Specific examples include epoxy resin, polyfunctional cyanate ester resin, polyfunctional maleimide-cyanate ester resin, polyfunctional maleimide resin, and unsaturated group-containing polyphenylene ether resin.
Use a combination of more than one type. Polyfunctional cyanate ester resin compositions are preferred from the viewpoints of heat resistance, moisture resistance, migration resistance, electrical properties after moisture absorption, and the like.

The polyfunctional cyanate compound which is a preferred thermosetting resin component of the present invention is a compound having two or more cyanato groups in the 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-cy (Anatophenyl) 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, a generally known epoxy resin can be used. Specifically, liquid or solid bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, alicyclic epoxy resin; butadiene, pentadiene, vinylcyclohexene, dicyclopentyl ether, etc. And polyglycidyl compounds obtained by reacting a polyol, a hydroxyl-containing silicone resin with an epohalohydrin, and the like. These may be used alone or in combination of two or more.

As the polyimide resin, generally known ones can be used. Specific examples include a reaction product of a polyfunctional maleimide and a polyamine, and a polyimide having a terminal triple bond described in JP-B-57-005406.

These thermosetting resins may be used alone, but it is preferable to use them in an appropriate combination in consideration of the balance of properties.

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, A
S resin, ABS resin, MBS resin, styrene-isoprene rubber, polyethylene-propylene copolymer, 4-fluoroethylene-6-fluoroethylene copolymers; polycarbonate, polyphenylene ether, polysulfone, polyester, polyphenylene sulfide, etc. High molecular weight prepolymers or oligomers; polyurethanes and the like are exemplified, and are appropriately used. Other known inorganic or organic fillers, dyes, pigments, thickeners, lubricants, defoamers, dispersants, leveling agents, photosensitizers, flame retardants, brighteners, polymerization inhibitors, thixotropic Various additives such as imparting agents are used in combination as needed. 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 economical efficiency. Can be used. The amount used is 0.005 to 10 parts by weight, preferably 0.01 to 5 parts by weight, per 100 parts by weight of the thermosetting resin.

As the reinforcing base material of the prepreg, generally known inorganic or organic woven or nonwoven fabric is used. Specific examples include known glass fiber cloths such as E glass, S glass, and D glass, wholly aromatic polyamide fiber cloths, and liquid crystal polyester fiber cloths. These may be mixed. The base material has a density such that the protrusions penetrate between the base materials during lamination molding.

A generally known metal foil can be used as the facing metal foil. Preferably, a copper foil, a nickel foil or the like having a thickness of 3 to 18 μm is used. It is preferable that the material is the same as the metal foil forming the truncated cone-shaped protrusion, from the viewpoint of preventing warpage.

The truncated conical through-hole replacement projections formed on the metal plate are not particularly limited, but the bottom adhered to the metal plate is generally 0.2-1.0 mm, and the top is 0-1.0 mm.
It is good to form to 0.5mm. If the top is 0 mm and the tip is sharp, it should be pierced into the facing metal foil during lamination and connected. In this case, the tip may be crushed and flattened.

When preparing the prepreg for a printed wiring board of the present invention, the substrate is impregnated with a thermosetting resin composition and dried to obtain a semi-cured laminated material. Also, a resin sheet in a semi-cured state without using a base material can be used. Alternatively, paints can be used. The temperature at which a prepreg or the like is formed is generally 100 to 180 ° C. The time is 5-60 minutes.

The method of producing the semiconductor plastic package containing the metal core of the present invention is not particularly limited. For example, the following method shown in FIG. 1 is used. (1) Both sides of the metal plate are covered with a liquid etching resist,
After heating to remove the solvent, the resist on the portion that will become a through hole on one side is removed leaving a circular shape, the entire resist is left on the lower side, and a truncated cone-shaped projection f is formed on the upper side by etching. A metal plate c is created. A conductive adhesive d is adhered onto the truncated cone, a prepreg B (b) slightly thinner than the truncated cone is placed thereon, and a metal foil a is placed above the prepreg B (b). (2) Laminate under heat, pressure and vacuum to integrate. (3) If the metal foil is thick, remove the thick side by etching to match the thickness of the metal foil on one side (Fig. 1, g). (4) Form circuits on the top and bottom, apply precious metal plating and print wiring Create a board.

[0027]

The present invention will be specifically described below with reference to examples and comparative examples. Unless otherwise specified, “parts” indicates parts by weight. Example 1 900 parts of 2,2-bis (4-cyanatophenyl) propane,
100 parts of (maleimidophenyl) methane are melted at 150 ° C,
The mixture was reacted for 4 hours while stirring to obtain a prepolymer. This was dissolved in a mixed solvent of methyl ethyl ketone and dimethylformamide. Add bisphenol A type epoxy resin (trade name: Epicoat 1001, Yuka Shell Epoxy Co., Ltd.)
) And 600 parts of a cresol novolac type epoxy resin (trade name: ESCN-220F, manufactured by Sumitomo Chemical Co., Ltd.) were uniformly mixed and dissolved. Further, as a catalyst, zinc octylate 0.4
Were added and dissolved and mixed. To this, 500 parts of an inorganic filler (trade name: calcined talc BST-200, manufactured by Nippon Talc Co., Ltd.) was added, followed by uniform stirring and mixing to obtain Varnish A. This is impregnated in a 50 μm glass woven fabric, dried, and gelled (at 170 ° C.) 103 seconds,
A prepreg (laminate material B) having an insulating layer thickness of 75 μm was prepared. On the other hand, Cu with a thickness of 120 μm to become the inner metal plate: 99.9%, F
e: Prepare a 0.07%, P: 0.03% alloy plate, apply liquid etching resist 25μm on the upper and lower sides and dry, size 50m on the surface
350μm diameter at the through hole forming part of m square package
Cover the negative film created so that the resist remains,
Etching, frustoconical upper diameter 130μm, lower diameter 60
A projection having a height of 0 μm and a height of 80 μm was formed. Also, 400 frusto-conical projections are similarly formed within the 13 mm square area of the semiconductor chip mounting area, and a silver paste of 6 μm thickness is deposited on these projections,
The laminated material B is arranged on the upper side, an 18 μm electrolytic copper foil is placed on the outer side, and the laminated material is laminated and molded at 200 ° C., 20 kgf / cm ² , and a vacuum of 30 mmHg or less for 2 hours to have a through hole of a metal projection. A double-sided copper-clad laminate was obtained. After attaching an etching resist to this top surface, dissolving the thick lower copper foil surface with a chemical solution to 18 μm, forming a circuit, forming a plating resist other than the semiconductor chip mounting part, the bonding pad part and the temporary ball pad part Then, nickel and gold plating were applied to complete the printed wiring board. After bonding and fixing the semiconductor chip with silver paste, wire bonding is performed, then using a sealing epoxy resin compound containing silica, the semiconductor chip, wires and bonding pads are resin-sealed, and solder balls are joined to form a semiconductor plastic package. It was created. Table 1 shows the evaluation results.

Example 2 A semiconductor plastic package was prepared in the same manner as in Example 1 except that no silver paste was used. Table 1 shows the evaluation results.

Comparative Example 1 One prepreg B (b) of Example 1 was used, and
μm electrolytic copper foil a is placed, 200 ℃, 20kgf / cm ² , 30mmHg
Laminate molding was performed for 2 hours under the following vacuum to obtain a double-sided copper-clad laminate. Using this double-sided copper-clad laminate, place a 0.15
A through hole of mmφ was drilled, and the through hole was plated with copper (h, o). Circuits were formed on and under the plate by a known method, and were covered with a plating resist m and then plated with nickel and gold. This has a through hole o for heat dissipation formed at a place where a semiconductor chip is mounted. The semiconductor chip i was mounted in the region above this and sealed with resin (FIG. 2, n). Table 1 shows the evaluation results.

Comparative Example 2 Epoxy resin (trade name: Epicoat 5045) 700 parts and epoxy resin (trade name: ESCN220F) 300 parts, dicyandiamide 35
Part of 2-ethyl-4-methylimidazole was uniformly dissolved in a mixed solvent of methyl ethyl ketone and dimethylformamide, impregnated in a glass woven fabric having a thickness of 100 μm, and dried to prepare a prepreg having a gel time of 150 seconds (prepreg). D) and a prepreg (prepregs E and e) having a gelation time of 10 seconds were prepared. Use one prepreg D, 190 ℃, 20kgf / c
Laminate molding was performed for 2 hours under a vacuum of m ² and 30 mmHg or less to prepare a double-sided copper-clad laminate. Thereafter, a printed wiring board was prepared in the same manner as in Comparative Example 1, the semiconductor chip mounting portion was cut out using a counterbore machine, and a copper plate p having a thickness of 100 μm was punched out from the back using the prepreg E (e). Then, they were bonded under heat and pressure to prepare a printed wiring board with a heat sink. The semiconductor chip i is directly applied to this heat sink with silver paste k.
And bonded by wire bonding and sealed with a liquid epoxy resin n (FIG. 3). Table 1 shows the evaluation results.

[0031] Table 1 Item implementation example comparisons Example 1 2 1 2 after moisture absorption heat resistance ¹⁾ normal state No change No change No change No change 24hrs. No abnormality No abnormality No abnormality No abnormality 48hrs. No problem No No abnormalities No abnormalities 72hrs. No abnormalities No abnormalities No abnormalities Partial peeling 96hrs. No abnormalities No abnormalities Partial peeling Partial peeling 120hrs. No abnormalities No abnormalities Partial peeling Partial peeling 144hrs. No abnormalities No abnormalities Partial peeling Partial Peeling 168hrs. No abnormalities No abnormalities Partial peeling Partial peeling Heat resistance after moisture absorption ²⁾ Normal No abnormalities No abnormalities No abnormalities No abnormalities 24hrs. No abnormalities No abnormalities Partial peeling 48hrs. No abnormalities No abnormalities Partial Peeling Large peeling 72hrs. No abnormality No abnormality Large peeling Large wire breakage 96hrs. No abnormality No abnormality Wire breakage Wire 120hrs. No abnormality No abnormality Wire breakage 144hrs. No abnormality No abnormality − − 1 68hrs. No abnormality No abnormality--Glass transition temperature (° C) 234 234 234 160

[0032] Table 1 (Continued) Item implementation example comparisons Example 1 2 1 2 Pressure cooker treatment after the insulation resistance (Omega) normal state ^{5x10 14 5 × 10 14 6x10 14} 5x10 14 200hrs. 6x10 12 6 × 10 ^{.. 12 6x10 12 3x10 8 500hrs} 8x10 11 8 × 10 11 5x10 11 <10 8 700hrs 5x10 10 5 × 10 10 4x10 10 -. 1000hrs 2x10 10 2 × 10 10 3x10 10 - migration resistance (Omega) normal state 6x10 ^{13 ... 6 × 10 13 4x10} 13 6x10 13 200hrs 4x10 11 4 × 10 11 5x10 11 3x10 9 500hrs 6x10 11 6 × 10 11 4x10 11 <10 8 700hrs 3x10 11 3 × 10 11 1x10 11 -. 1000hrs 9x10 10 9 × 10 ¹⁰ 8 x ^{10 10} -Through-hole heat cycle test (%) 1.7 2.9 2.3 4.0 Heat dissipation 33 35 57 48

<Measurement method> 1) Heat resistance after moisture absorption ¹⁾ JEDEC STANDARD TEST METHOD A113-A LEVEL3: 30 ℃ ・ 60%
After the treatment with RH for a predetermined time, the presence or absence of an abnormality in the substrate after three cycles of reflow soldering at 220 ° C. was confirmed by cross-sectional observation and electrical check. 2) Electric insulation after moisture absorption ²⁾ JEDEC STANDARD TEST METHOD A113-A LEVEL2: 85 ℃ ・ 60%
After processing at RH for a predetermined time (Max. 168 hrs.), The presence or absence of abnormality in the substrate after three cycles of reflow soldering at 220 ° C. was confirmed by cross-sectional observation and electrical check. 3) Glass transition temperature Measured by the DMA method. 4) Insulation resistance after pressure cooker process A comb-shaped pattern between terminals (line / space = 70/70 μm) is created, and the prepreg or resin layer used is formed on each of these patterns and cured by heating. Was treated at 121 ° C. and 2 atm for a predetermined period of time, followed by post-treatment at 25 ° C. and 60% RH for 2 hours, and after applying 500 VDC for 60 seconds, the insulation resistance between the terminals was measured. 5) Migration resistance The test piece of the above 4) was applied at 85 ° C. and 85% RH at 50 VDC, and the insulation resistance between the terminals was measured. 6) Through-hole heat cycle test A land diameter of 200 μm is created in each through-hole, and 900 holes are connected alternately on the front and back.
200 cycles were performed from 0 seconds to 5 minutes at room temperature, and the maximum value of the rate of change in resistance was shown. 7) Heat dissipation The package was connected to the same motherboard printed wiring board with solder balls and used continuously for 1000 hours before measuring the package temperature.

[0034]

The present invention is a printed wiring board manufactured by manufacturing a double-sided metal foil-clad laminate by a dry system without using a chemical solution such as desmear treatment and through-hole plating. The obtained printed wiring board has excellent through-hole reliability, heat dissipation, and mass productivity. That is, a truncated cone-shaped projection is formed on at least one position of the metal plate at a position where a through-hole is formed, and if necessary, a surface chemical treatment is performed, and a conductive adhesive is adhered onto the truncated cone-shaped projection or the truncated cone-shaped projection. A semi-cured prepreg, resin sheet, resin-coated metal foil or coated resin layer, which is slightly thinner than the height of the protrusions, is placed on the protrusion side of the metal plate, and the outside of the resin layer to which the metal foil is not attached is provided. A circuit is formed by using a double-sided metal foil-clad laminate obtained by disposing a metal foil, laminating under heat and pressure, preferably under vacuum, and joining the metal foil directly or by using a conductive adhesive. Then, noble metal plating is applied to at least the wire bonding pads to obtain a printed wiring board. It is preferable to use a polyfunctional cyanate resin composition as the resin layer.
The resulting printed wiring board has heat resistance, insulation after moisture absorption,
New structure with excellent migration resistance, insulation after pressure cooker treatment, etc., excellent connection reliability by heating through-holes, and also suitable for mass productivity, with improved economic efficiency Was obtained.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of a printed wiring board of Example 1.

FIG. 2 is a manufacturing process diagram of the printed wiring board of Comparative Example 1.

FIG. 3 is a manufacturing process diagram of the printed wiring board of Comparative Example 2.

[Explanation of symbols]

 a Metal foil b Pre-preg B c Single-sided truncated conical metal plate d Conductive adhesive e Pre-preg E f Truncated conical projection g Etched copper foil h Through-hole for front and back circuit conduction i Semiconductor chip j Bonding wire k Silver paste l Solder ball m Plating resist n Sealing resin o Heat dissipation through hole p Copper plate

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshihiko Kobayashi F-term (reference) 5E315 AA11 CC15 CC16 DD05 DD13 GG01 GG11 GG13 5E317 AA24 in the Tokyo Plant, Mitsubishi Gas Chemical Co., Ltd. 6-1-1-1 Shinjuku, Katsushika-ku, Tokyo AA30 BB01 BB12 BB14 BB18 CC33 CD05 GG09 GG17 5E346 AA41 CC02 CC08 CC32 CC38 CC39 CC40 CC42 DD02 DD12 DD22 EE02 EE08 EE09 EE12 EE13 FF22 FF24 FF36 FF41 GG08 GG27 GG28 HH11 HH33

Claims (4)

[Claims] 1. A frustum-shaped projection is formed on at least one side of a metal plate at a position where a through-hole is formed, and a semi-cured prepreg, a resin sheet, which is slightly thinner than the height of the projection, is formed on the frustum-shaped projection side. A metal foil with resin or a coating resin layer is placed, and a metal foil is placed outside the resin layer without the metal foil, and laminated under heat and pressure, and the tip of the frustoconical projection comes into contact with the metal foil. A method for producing a printed wiring board, comprising: forming a double-sided metal foil-clad laminate, forming a circuit on the front and back, and performing noble metal plating. 2. The printed wiring board according to claim 1, wherein a conductive adhesive is adhered to the tip of the truncated cone-shaped projection, laminated and formed under heat and pressure, and the tip of the projection is joined to the metal foil. Production method. 3. The method for manufacturing a printed wiring board according to claim 1, wherein said metal plate is a copper alloy containing 95% by weight or more of copper or pure copper. 4. An insulating resin composition used for a prepreg, a resin sheet, a metal foil with a resin, or a coating resin layer, comprising a polyfunctional cyanate ester, and a thermosetting resin containing the cyanate ester prepolymer as an essential component. 3. The method for producing a printed wiring board according to claim 1, which is a composition.