US4893404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing a multilayer printed wiring board
Assignee: FURUKAWA DENKI KOGYO 6-1 MARUNOUCHI 2-CHOME CHIYODA-KU TOKYO JAPAN A CORP OF JAPAN KK
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Filing: 1988-09-13
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Granted: 1990-01-16
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Expires: 2008-09-13
Abstract
Abstract A method for producing a multilayer printed wiring board by the buildup process. A first layer printed wiring pattern (13) is formed on a metal core (11) over a first insulating laminate (12), and second layer printed wiring pattern (16) is formed on the first layer printed wiring pattern over through studs (15) and a second insulating laminate (14). The surface of the first layer printed wiring pattern (13) is roughened and the through studs (15) are formed by the buildup process using a conductive paste on the roughened surface.
Inventors
- 👤 Isao Shirahata
- 👤 Shoji Shiga
- 👤 Hisako Hori
- 👤 Takamasa Jinbo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:05
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4644; H05K3/4664; H05K1/00; H05K1/02; H05K1/03; H05K1/05; H05K1/056; H05K3/4647; H05K1/0313; H05K1/0353; H05K1/0366; H05K1/09; H05K1/092; H05K1/095; H05K2201/00; H05K2201/02; H05K2201/0203; H05K2201/0206; H05K2201/0209; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0347; H05K2201/0355; H05K2203/00; H05K2203/07; H05K2203/0703; H05K2203/072; H05K3/22; H05K3/24; H05K3/245; H05K3/246; H05K3/38; H05K3/382; H05K3/40; H05K3/4038; H05K3/4053; H05K3/4069; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49155; Y10T29/49165
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
201 words
A method for producing a multilayer printed wiring board comprising the following steps: (a) forming a first layer of printed wiring pattern by a subtractive process on a metal foil layer of a metal foil-clad insulated metal core comprising a metal foil having at least one surface thereof roughened such that an average value of differences in height between peaks and valleys thereof is at least 1 μm and a metal core to which said metal foil is bonded through a first insulating laminate, with said roughened surface serving as a nonbonding surface; (b) curing a resin-type conductive paste to form a plurality of through studs for current flow between said first layer of printed wiring pattern and a second layer of printed wiring pattern to be formed next and forming a second insulating laminate for providing insulation spaces of said first layer of printeed wiring pattern and between said first and second layers of printed wiring patterns; and (c) forming said second layer of printed wiring pattern by screen printing a resin-type conductive paste in a desired pattern on the surface of said through studs and said second insulating laminate, curing said conductive paste and applying an electrodeless plating thereto.
Claim 2
Independent Claim
201 words
A method for producing a multilayer printed wiring board comprising the following steps: (a) forming a first layer of printed wiring pattern by a subtractive process on a metal foil layer of a metal foil-clad insulated metal core comprising a metal foil having at least one surface thereof roughened such that an average value of differences in height between peaks and valleys thereof is at least 1 μm and a metal core to which said metal foil is bonded through a first insulating laminate, with said roughened surface serving as a nonbonding surface; (b) curing a resin-type conductive paste to form a plurality of through studs for current flow between said first layer of printed wiring pattern and a second layer of printed wiring pattern to be formed next and forming a second insulating laminate for providing insulation spaces of said first layer of printeed wiring pattern and between said first and second layers of printed wiring patterns; and (c) forming said second layer of printed wiring pattern by screen printing a resin-type conductive paste in a desired pattern on the surface of said through studs and said second insulating laminate, curing said conductive paste and applying an electrodeless plating thereto.
Claim 3
Dependent Claim
77 words
A method according to claim 1, wherein in said step (a), said metal foil-clad insulating metal core is formed by bonding together under the application of heat and pressure a metal foil having at least one surface thereof roughened such that an average value of differences in height between peaks and valleys thereof is at least ;b 1 μm and a metal core through a first insulating lamination, with said roughened surface serving as a nonbonding surface.
Claim 4
Dependent Claim
68 words
A method according to claim 1, wherein said step (a), said metal foil-clad insulating metal core is formed by bonding together a metal foil and a metal core through a first insulating laminate under the application of heat and pressure and then roughening a surface of said metal foil such that an average value of differences in height between peaks and valleys thereof is at least 1 μm.
Claim 5
Dependent Claim
26 words
A method according to claim 1, wherein in said step (a), said first insulating laminate is a composite material comprising a resin and an inorganic material.
Claim 6
Dependent Claim
30 words
A method according to claim 4, wherein said resin comprises a material selected from the group consisting of epoxy, phenol, polyamide-imide, polyimide, nitrile-rubber modified phenol and butyral modified phenol resins.
Claim 7
Dependent Claim
25 words
A method according to claim 4, wherein said inorganic material comprises a material selected from the group consisting of powdered talc, quartz, alumina and titania.
Claim 8
Dependent Claim
31 words
A method according to claim 1, wherein said first insulating lamination is a laminate comprising a plurality of different composite materials, each composite material comprising a resin and an inorganic material.
Claim 9
Dependent Claim
47 words
A method according to claim 1, wherein in said step (b), said second insulating laminate for providing insulation spaces of said first layer of printed wiring pattern and between said first and second layers of printed wiring patterns is formed after the formation of said through studs.
Claim 10
Dependent Claim
63 words
A method according to claim 1, wherein in said step (b), said through studs are formed after the formation of a part of said second insulating laminate for providing insulation spaces of said first layer of printed wiring pattern, and then the remainder of said second insulating laminate for providing insulation between said first and second layers of printing wiring patterns is formed.
Claim 11
Dependent Claim
48 words
A method according to claim 1, wherein in said step (b), said second insulating laminate for providing insulation spaces of said first layer of printed wiring pattern and between said first and second layers of printed wiring patterns is formed first and then said through studs are formed.
Claim 12
Dependent Claim
26 words
A method according to claim 1, wherein in said step (b), said second insulating laminate is a composite material comprising a resin and an inorganic material.
Claim 13
Dependent Claim
31 words
A method according to claim 11, wherein said resin comprises a material selected from the group consisting of epoxy, phenol, polyamide-imide, polyimide, nitrile-rubber modified phenol, butyral modified phenol, and acrylic resins.
Claim 14
Dependent Claim
31 words
A method according to claim 11, wherein said inorganic material comprises a material selected from the group consisting of powdered talc, clay, barium sulfate, calcium carbonate, quartz, silica, alumina and titania.
Claim 15
Dependent Claim
31 words
A method according to claim 1, wherein said second insuating laminate is a laminate comprising a plurality of different composite materials, each composite material comprising a resin and an inorganic material.
Claim 16
Dependent Claim
37 words
A method according to claim 1, wherein said step (c) is performed after the surface of said through studs and said second insulating laminate have been made flat by mechanical grinding immediately before performing said step (c).
Claim 17
Dependent Claim
54 words
A method according to claim 1, wherein in said step (c), said second layer of printed wiring pattern is formed by forming a desired wiring pattern with a resin-type conductive paste, applying a nickel-boron alloy electrodeless plating to said desired wiring pattern and applying a copper electrodeless plating to said nickel-boron alloy electrodeless plating.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-15 | 1993-07-17 | 1994-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-15 | 1997-07-17 | 1998-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-15 | 2001-07-17 | 2002-01-16 | $7700.00 | Window Closed / Lapsed |