US5725808A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multilayer co-fired ceramic compositions and ceramic-on-metal circuit board
Assignee: Sharp Corp
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Filing: 1996-05-23
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Granted: 1998-03-10
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Expires: 2016-05-23
Abstract
Abstract A ceramic mixture of a crystallizable ZnO-MgO-B2O3-SiO2 glass mixed with a non-crystallizing lead-based glass and one or more oxide fillers forms a fired ceramic that has a TCE compatible with that of kovar. Green tapes made from the ceramic mixture aligned with a kovar support substrate when fired have excellent dielectric and low loss properties.
Inventors
- 👤 Ellen Schwartz Tormey
- 👤 Ashok Naryan Prabhu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:48
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/69; C; C03; C03C; C03C10/00; C03C10/0054; C03C3/00; C03C3/04; C03C3/062; C03C3/064; C03C3/066; C03C3/07; C03C3/072; C03C3/074; C03C8/00; C03C8/14; C03C8/22; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/05; H05K1/053
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
51 words
A crystallizable glass composition comprising from 25-30% by weight of ZnO, from 20-28% by weight of MgO, from 15-20% by weight of B 2 O 3 , from 20-30% by weight of SiO 2 , up to 10% weight of Al 2 O 3 , and Co 3 O 4 .
Claim 2
Dependent Claim
51 words
A crystallizable glass composition comprising from 25-30% by weight of ZnO, from 20-28% by weight of MgO, from 15-20% by weight of B 2 O 3 , from 20-30% by weight of SiO 2 , up to 10% weight of Al 2 O 3 , and Co 3 O 4 .
Claim 3
Dependent Claim
27 words
A ceramic mixture of a glass of claim 1 and a non-crystallizing glass wherein said non-crystallizing glass contains PbO, Al 2 O 3 and SiO 2 .
Claim 4
Dependent Claim
54 words
A ceramic mixture of claim 2 wherein said non-crystallizing glass contains from 30-80% by weight of PbO, from 15-50% by weight of SiO 2 , up to 10% by weight of Al 2 O 3 , up to 15% by weight of B 2 O 3 and up to 10% by weight of ZnO.
Claim 5
Dependent Claim
13 words
A ceramic mixture of claim 2 wherein said non-crystallizing glass additionally contains ZnO.
Claim 6
Dependent Claim
11 words
A ceramic mixture of claim 2 further including an oxide filler.
Claim 7
Dependent Claim
13 words
A ceramic mixture of claim 2 further including two or more oxide fillers.
Claim 8
Dependent Claim
24 words
A ceramic mixture of claim 4 wherein said oxide filler is selected from the group consisting of alumina, cordierite, quartz, cristobalite, forsterite and willemite.
Claim 9
Dependent Claim
52 words
A green tape composition comprising from 40-75% by weight of a ceramic mixture of the glass of claim 1, from 1.2 to 22.5% by weight of a non-crystallizing glass containing PbO, Al 2 O 3 and SiO 2 , from 2 to 45% by weight of oxide fillers, and an organic vehicle.
Claim 10
Dependent Claim
16 words
A green tape composition of claim 8 comprising from 70-75% by weight of said ceramic mixture.
Claim 11
Dependent Claim
13 words
A fired green tape composition of claim 8 on a metal support substrate.
Claim 12
Dependent Claim
14 words
A fired green tape composition of claim 8 on a a ferro/nickel/cobalt alloy support.
Claim 13
Dependent Claim
19 words
A fired green tape composition of claim 11 wherein said a ferro/nickel/cobalt alloy support has a bonding glass thereon.
Claim 14
Dependent Claim
19 words
A fired green tape composition of claim 12 wherein said bonding glass is a calcium oxide-aluminum oxide-zinc oxide-borate glass.
Claim 15
Dependent Claim
32 words
A low melting temperature conductive ink composition comprising a conductive metal powder selected from the group consisting of silver, gold and copper, the ceramic mixture of claim 2 and an organic vehicle.
Claim 16
Dependent Claim
20 words
A printed circuit board comprising a metal support adhered to a fired ceramic made from the composition of claim 2.
Claim 17
Dependent Claim
22 words
A printed circuit board comprising a a ferro/nickel/cobalt alloy support adhered to a fired ceramic made from the composition of claim 8.
Claim 18
Dependent Claim
22 words
A printed circuit board of claim 16 wherein said fired ceramic is adhered to both sides of said a ferro/nickel/cobalt alloy support.
References Cited (Backward Citations)
GB1151860A
Cited
US4358541A
Cited
US4547467A
Cited
US4830988A
Cited
US5001087A
Cited
US5581876A
Cited
US5491116A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-03-09 | 2001-09-08 | 2002-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-03-09 | 2005-09-08 | 2006-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-03-09 | 2009-09-08 | 2010-03-10 | $7700.00 | Window Closed / Lapsed |