US5117069A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit board fabrication
Assignee: Computervision Corp
•
Filing: 1990-09-28
•
Granted: 1992-05-26
•
Expires: 2010-09-28
Abstract
Abstract A high density multi-level printed wiring board having inter-level electrical connections made by via interconnect holes which are drilled or punched through only those layers of the wiring board that separate the two layers containing the conductors which are to be connected and said holes being filled with a low-resistance silver-filled conductive epoxy.
Inventors
- 👤 Leo M. Higgins, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:00
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4611; H05K3/4614; H05K3/4617; H05K1/00; H05K1/02; H05K1/11; H05K1/111; H05K1/112; H05K1/113; H05K3/40; H05K3/4038; H05K3/4053; H05K3/4069; H05K2201/00; H05K2201/01; H05K2201/0183; H05K2201/0195; H05K2201/03; H05K2201/0302; H05K2201/0305; H05K2201/09; H05K2201/09209; H05K2201/095; H05K2201/096; H05K2203/00; H05K2203/14; H05K2203/1453; H05K3/22; H05K3/28; H05K3/4007; Y; Y10; Y10S; Y10S428/00; Y10S428/901
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
185 words
A printed circuit apparatus comprising a plurality of separate circuit board layers, each board layer comprising a laminate layer having conductive runs thereon and a pre-preg insulating layer; means securing the board layers in a sandwiched array; means defining a continuous interconnecting hole in at least two adjacently disposed circuit board layers between at least two conductive runs on separate laminate circuit board layers; and a curable electrically conductive adhesive disposed within said interconnecting hole providing an electrically conductive bridge between said at least two conductive runs, the interconnecting hole as well as the electrically conductive bridge passing only between said at least two conductive runs, wherein one of said at least two conductive runs is disposed on a first of said plurality of circuit board players, having at least one additional layer above it, and the other of said at least two conductive runs is disposed on a second of said plurality of circuit board layers, having at least one additional layer below it, wherein there are no other interconnecting holes on the plurality of circuit board layers in alignment with said interconnecting hole.
Claim 2
Dependent Claim
185 words
A printed circuit apparatus comprising a plurality of separate circuit board layers, each board layer comprising a laminate layer having conductive runs thereon and a pre-preg insulating layer; means securing the board layers in a sandwiched array; means defining a continuous interconnecting hole in at least two adjacently disposed circuit board layers between at least two conductive runs on separate laminate circuit board layers; and a curable electrically conductive adhesive disposed within said interconnecting hole providing an electrically conductive bridge between said at least two conductive runs, the interconnecting hole as well as the electrically conductive bridge passing only between said at least two conductive runs, wherein one of said at least two conductive runs is disposed on a first of said plurality of circuit board players, having at least one additional layer above it, and the other of said at least two conductive runs is disposed on a second of said plurality of circuit board layers, having at least one additional layer below it, wherein there are no other interconnecting holes on the plurality of circuit board layers in alignment with said interconnecting hole.
Claim 3
Dependent Claim
34 words
A printed circuit apparatus as set forth in claim 1 wherein at least some of said circuit board layers each are comprised of a laminate layer having the conductive run formed thereon by etching.
Claim 4
Dependent Claim
31 words
A printed circuit apparatus as set forth in claim 2 wherein said at least some of said circuit board layers each are also comprised of a fiberglass reinforced polymer pre-preg layer.
Claim 5
Dependent Claim
24 words
A printed circuit apparatus as set forth in claim 1 wherein said adhesive comprises an epoxy paste with fine electrically conductive particles suspended therein.
Claim 6
Dependent Claim
24 words
A printed circuit apparatus as set forth in claim 4 wherein said particles represent on the order of 80% by weight of the adhesive.
Claim 7
Dependent Claim
23 words
A printed circuit apparatus as set forth in claim 4 wherein said particles are selected from a group consisting of silver and copper.
Claim 8
Dependent Claim
22 words
A printed circuit apparatus as set forth in claim 1 wherein said hole has a diameter in the range of 1-18 mm.
Claim 9
Dependent Claim
18 words
A printed circuit apparatus as set forth in claim 1 wherein said interconnecting hole is a blind hole.
References Cited (Backward Citations)
US4383363A
Cited
US4851615A
Cited
US4650923A
Cited
US4685033A
Cited
US4679122A
Cited
US4672152A
Cited
US4827083A
Cited
US4847146A
Cited
US4967314A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-05-26 | 1995-11-25 | 1996-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-26 | 1999-11-25 | 2000-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-26 | 2003-11-25 | 2004-05-26 | $7700.00 | Window Closed / Lapsed |