Patent US4863517A successfully refreshed from Google Patents.
US4863517A
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Via fill ink composition for integrated circuits
Assignee: Lockheed Martin Corp
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Filing: 1988-10-11
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Granted: 1989-09-05
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Expires: 2008-10-11
Abstract
Abstract A novel devitrifying frit is disclosed which has a coefficient of expansion essentially the same as that of silicon. The subject frits have a high softening temperature and excellent reheat stability which make them useful in ink formulations for forming dielectric layers in multilayer circuitry. The frits are also suitable for use as a substrate material for direct mounting of silicon chips or for use in thick film via-fill inks.
Inventors
- 👤 Kenneth W. Hang
- 👤 Ashok N. Prabhu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:14
CPC Classifications
C; C03; C03C; C03C8/00; C03C8/02; C03C8/08; H; H05; H05K; H05K1/00; H05K1/02; H05K1/09; H05K1/092
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
129 words
A via-fill ink comprising, on a weight basis: (a) from about 50 to about 70 percent of copper powder; (b) from about 15 to about 35 percent of a devitrifying glass frit comprising, on a weight basis: from about 19 to about 25 percent of zinc oxide; from about 5 to about 20 percent of barium oxide; from about 10 to about 30 percent of aluminum oxide; from about 30 to about 50 percent of silicon dioxide; from about 1 to about 6 percent of magnesium oxide, calcium oxide or mixtures thereof; from about 0.5 to about 3 percent of phosphorus pentoxide; and a form * about 1 to about 5 percent of zirconium silicate; and (c) from about 5 to about 25 percent of a suitable organic vehicle.
Claim 2
Dependent Claim
129 words
A via-fill ink comprising, on a weight basis: (a) from about 50 to about 70 percent of copper powder; (b) from about 15 to about 35 percent of a devitrifying glass frit comprising, on a weight basis: from about 19 to about 25 percent of zinc oxide; from about 5 to about 20 percent of barium oxide; from about 10 to about 30 percent of aluminum oxide; from about 30 to about 50 percent of silicon dioxide; from about 1 to about 6 percent of magnesium oxide, calcium oxide or mixtures thereof; from about 0.5 to about 3 percent of phosphorus pentoxide; and a form * about 1 to about 5 percent of zirconium silicate; and (c) from about 5 to about 25 percent of a suitable organic vehicle.
Claim 3
Dependent Claim
93 words
A via-fill in accordance with claim 1 wherein the devitrifying glass frit comprises, on a frit weight basis: from about 21 to about 23 percent of zinc oxide; from about 7 to about 15 percent of barium oxide; from about 13 to about 22 percent of aluminum oxide; from about 35 to about 45 percent of silicon dioxide; from about 2 to about 4.5 percent of magnesium oxide, calcium oxide or mixtures thereof; from about 0.5 to about 1.5 percent of phosphorus pentoxide; and from about 2 about 5 percent of zirconium silicate.
Claim 4
Dependent Claim
55 words
A via-fill ink in accordance with claim 1 wherein the ink comprises, on a weight basis: (a) from about 50 to about 60 percent of the copper powder; (b) from about 20 to about 32 percent of the devitrifying glass frit; and (c) from about 15 to about 20 percent of the suitable organic vehicle.
Claim 5
Dependent Claim
90 words
A via-fill ink in accordance with claim 3 wherein the devitrifying flass* frit comprises, on a frit weight basis: from about 21 to about 23 percent of zinc oxide; from about 7 to about 15 percent of barium oxide; from about 13 to about 22 percent of aluminum oxide; from about 35 to about 45 percent of silicon dioxide; from about 2 to about 4.5 percent of magnesium oxide; from about 0.5 to about 1.5 percent of phosphorus pentoxide; and from about 2 to about 5 percent of zirconium silicate.
Claim 6
Dependent Claim
24 words
A via-fill ink in accordance with claim 4 wherein the suitable organic vehicle comprises a solution of an organic binder in a suitable solvent.
Claim 7
Dependent Claim
24 words
A via-fill ink in accordance with claim 5 wherein the organic binder is selected from the group consisting of poly (isobutylmethacrylate) and ethyl cellulose.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-04 | 1993-03-06 | 1993-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-04 | 1997-03-06 | 1997-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-04 | 2001-03-06 | 2001-09-05 | $7700.00 | Window Closed / Lapsed |