US4131516A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making metal filled via holes in ceramic circuit boards
Assignee: International Business Machines Corp
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Filing: 1977-07-21
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Granted: 1978-12-26
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Expires: 1997-07-21
Abstract
Abstract A ceramic substrate is provided with via holes and these holes are primed by first depositing a palladium coating to the inside surface of the holes and then depositing an iron film onto the palladium. The primed holes are then completely filled with copper to provide conductive connections between opposite surfaces of the substrate. On one side of the substrate, input/output connector pins are brazed to the copper fillings. On the other side, printed circuitry is applied to produce a circuit module.
Inventors
- 👤 Peter Bakos
- 👤 John Rasile
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:04
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/328; H05K3/40; H05K3/4038; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K2201/00; H05K2201/09; H05K2201/09209; H05K2201/09372; H05K2201/09481; H05K2201/095; H05K2201/09563; H05K2201/10; H05K2201/10227; H05K2201/10234; H05K2201/1031; H05K2201/10318; H05K2201/10613; H05K2201/10954; H05K2201/10962; H05K2203/00; H05K2203/11; H05K2203/1105; H05K2203/12; H05K2203/128; H05K3/34; H05K3/3465; H05K3/4007; H05K3/4015; H05K3/4046; H05K3/42; H05K3/423; H05K3/424; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12771; Y10T428/12861; Y10T428/12903; Y10T428/12917
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
61 words
A method of making conductive connections in via holes in printed circuit boards which comprises; depositing in the via holes a thin film of palladium metal; depositing a primer coat of a thin film of iron on said palladium film; and completely filling the primed via holes with copper to provide conductive connections between opposite surfaces of a printed circuit board.
Claim 2
Independent Claim
61 words
A method of making conductive connections in via holes in printed circuit boards which comprises; depositing in the via holes a thin film of palladium metal; depositing a primer coat of a thin film of iron on said palladium film; and completely filling the primed via holes with copper to provide conductive connections between opposite surfaces of a printed circuit board.
Claim 3
Dependent Claim
27 words
A method as defined in claim 1 and including brazing indium-copper-silver input-output connector pins to the ends of the copper connections on one side of the board.
Claim 4
Independent Claim
63 words
A method of making conductive connections in via holes in a ceramic substrate which comprises; dip coating in the via holes a thin film of palladium metal; electrolytically depositing a primer coat of a thin film of iron on said palladium film; and melting copper to completely fill the primed via holes to provide conductive connections between opposite surfaces of said ceramic substrate.
Claim 5
Independent Claim
63 words
A method of making conductive connections in via holes in a ceramic substrate which comprises; dip coating in the via holes a thin film of palladium metal; electrolytically depositing a primer coat of a thin film of iron on said palladium film; and melting copper to completely fill the primed via holes to provide conductive connections between opposite surfaces of said ceramic substrate.
Claim 6
Dependent Claim
41 words
The method defined in claim 3 and further including; selectively depositing metallized circuitry on at least one surface of said ceramic substrate; and brazing input-output connector pins to the ends of the copper connections on one side of the ceramic substrate.
Claim 7
Independent Claim
81 words
A method of making conductive connections in via holes in a ceramic substrate which comprises; depositing in the via holes a thin film of palladium metal having a thickness of 25-150 micro-inches; depositing a primer coat of a thin film of iron on said palladium film, said iron film having a thickness of 70-150 micro-inches so that it is non-porous; and melting copper to completely fill the primed via holes to provide conductive connections between opposite surfaces of said ceramic substrate.
Claim 8
Independent Claim
81 words
A method of making conductive connections in via holes in a ceramic substrate which comprises; depositing in the via holes a thin film of palladium metal having a thickness of 25-150 micro-inches; depositing a primer coat of a thin film of iron on said palladium film, said iron film having a thickness of 70-150 micro-inches so that it is non-porous; and melting copper to completely fill the primed via holes to provide conductive connections between opposite surfaces of said ceramic substrate.
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) | 1981-12-25 | 1982-06-26 | 1982-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-25 | 1986-06-26 | 1986-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-25 | 1990-06-26 | 1990-12-26 | $7700.00 | Window Closed / Lapsed |