US3627902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Interconnections for multilayer printed circuit boards
Assignee: Control Data Corp
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Filing: 1970-02-02
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Granted: 1971-12-14
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Expires: 1990-02-02
Abstract
Abstract A reliable mechanical and electrical connection between interior conductive layers and exterior conductive layers of a multilayer printed circuit board is provided. Shoulders are formed on the internal conductive layers at the location where connection is desired. A hole is then drilled through the assembly, passing through the shoulder. The wall of the hole is then electroformed with a conductive metal which makes connection at the formed shoulder. The added thickness of the shoulder combined with the pad area on the interior conductive layer provides a relatively large area and a more reliable interconnection.
Inventors
- 👤 Steven C Meyers
- 👤 Larry G Bergman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:52
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/40; H05K3/42; H05K3/429; H05K1/00; H05K1/02; H05K1/0271; H05K1/11; H05K1/115; H05K1/116; H05K2201/00; H05K2201/09; H05K2201/09209; H05K2201/09372; H05K2201/09454; H05K2201/09654; H05K2201/09736
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
111 words
A multilayer printed circuit board comprising: a. a plurality of insulating layers: b. a plurality of conductive layers, at least one of which is internal and sandwiched between two of the insulating layers; c. at least one feed-through hole whose wall has an electrically conductive coating and which penetrates all of the insulating layers and all of the conductive layers; and d. a formed shoulder integral with and upon the internal conductive layer, surrounding the feed-through hole and creating thereabout a thickened section of the internal conductive layer, having at least its periphery overlapped by the adjacent insulating layer, and electrically and mechanically connected with the conductive coating in the hole.
Claim 2
Dependent Claim
111 words
A multilayer printed circuit board comprising: a. a plurality of insulating layers: b. a plurality of conductive layers, at least one of which is internal and sandwiched between two of the insulating layers; c. at least one feed-through hole whose wall has an electrically conductive coating and which penetrates all of the insulating layers and all of the conductive layers; and d. a formed shoulder integral with and upon the internal conductive layer, surrounding the feed-through hole and creating thereabout a thickened section of the internal conductive layer, having at least its periphery overlapped by the adjacent insulating layer, and electrically and mechanically connected with the conductive coating in the hole.
Claim 3
Dependent Claim
21 words
The invention of claim 1 wherein the electrically conductive coating of the wall of the feed-through hole Is an electroplated metal.
Claim 4
Dependent Claim
12 words
The invention of claim 1 wherein the formed shoulder is electroplated metal.
Claim 5
Dependent Claim
102 words
A multilayer printed circuit board comprising: a. at least two insulating layers; b. at least three conductive layers, one of which is internal and sandwiched between said two insulating layers; c. at least one feed-through hole whose wall is electroplated with electrically conductive metal and which penetrates all insulating layers and all conductive layers; and d. an electroplated shoulder, integral with and upon the internal conductive layer, surrounding the feed-through hole and creating thereabout a thickened section of the internal conductive layer, having at least its periphery overlapped by the adjacent insulating layer, and electrically and mechanically connected to the electroplated wall.
Claim 6
Dependent Claim
102 words
A multilayer printed circuit board comprising: a. at least two insulating layers; b. at least three conductive layers, one of which is internal and sandwiched between said two insulating layers; c. at least one feed-through hole whose wall is electroplated with electrically conductive metal and which penetrates all insulating layers and all conductive layers; and d. an electroplated shoulder, integral with and upon the internal conductive layer, surrounding the feed-through hole and creating thereabout a thickened section of the internal conductive layer, having at least its periphery overlapped by the adjacent insulating layer, and electrically and mechanically connected to the electroplated wall.
Claim 7
Dependent Claim
16 words
The invention of claim 4 wherein the electroplated shoulder is at least 0.001 inches in thickness.
Claim 8
Independent Claim
124 words
A method of manufacturing a multilayer printed circuit board comprising the steps of: a. forming a first conductive circuit pattern on an insulating layer; b. conforming a masking material to the contours of the conductive circuit pattern; c. forming at least one aperture in the masking material; d. electroforming a conductive shoulder within at least one aperture in the masking material; e. removing the masking material, resulting in a completed subassembly; f. connecting the subassembly to the insulating layer side of an insulating layer having a conductive layer affixed thereto; g. forming at least one feed-through hole passing through the conductive shoulder; and h. forming a conductive coating on the wall of the feed-through hole on both the conductive layers and the insulating layers.
Claim 9
Independent Claim
124 words
A method of manufacturing a multilayer printed circuit board comprising the steps of: a. forming a first conductive circuit pattern on an insulating layer; b. conforming a masking material to the contours of the conductive circuit pattern; c. forming at least one aperture in the masking material; d. electroforming a conductive shoulder within at least one aperture in the masking material; e. removing the masking material, resulting in a completed subassembly; f. connecting the subassembly to the insulating layer side of an insulating layer having a conductive layer affixed thereto; g. forming at least one feed-through hole passing through the conductive shoulder; and h. forming a conductive coating on the wall of the feed-through hole on both the conductive layers and the insulating layers.
References Cited (Backward Citations)
US3276106A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-13 | 1975-06-14 | 1975-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-13 | 1979-06-14 | 1979-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-13 | 1983-06-14 | 1983-12-14 | $7700.00 | Window Closed / Lapsed |