US4537863A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low temperature sealing composition
Assignee: Nippon Electric Glass Co Ltd
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Filing: 1983-08-10
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Granted: 1985-08-27
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Expires: 2003-08-10
Abstract
Abstract A sealing composition suitable for sealing alumina packages for integrated circuits at a temperature below about 450° C. for a short time of about 10 minutes. The composition is a mixture of 50-80 wt. % vitreous solder glass powder of PbO-B 2 O 3 system having a deformation point of 350° C. or less, 1-35 wt. % first ceramic powder and 1-45 wt. % second ceramic powder. The total amount of the first and second ceramic powders is 20-50 wt. %. The first ceramic comprises 68-75 wt. % ZnO, 23-28 wt. % SiO 2 and 0-8 wt. % Al 2 O 3 , and the second ceramic comprises 98-99.9 wt. % SnO 2 and 0.1-2 wt. % ZnO.
Inventors
- 👤 Ichiro Matsuura
- 👤 Fumio Yamaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:14
CPC Classifications
H; H10; H10W; H10W76/00; H10W76/60; C; C04; C04B; C04B37/00; C04B37/003; C04B37/005; C04B2235/00; C04B2235/65; C04B2235/656; C04B2235/6562; C04B2237/00; C04B2237/02; C04B2237/10; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/343; C04B2237/50; C04B2237/59; C04B2237/592; H10W90/00; H10W90/701; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
A low temperature sealing composition for a seal of high mechanical strength between two alumina ceramic parts to form a sealed package having a shearing strength of at least 310 kg, the sealing composition having a sealing temperature of no more than 450° C. and consisting essentially of a mixture of 50-80 wt.% of a vitreous solder glass powder of PbO-B 2 O 3 system having a deformation point of 350° C. or less, 1-35 wt.% of a first ceramic powder and 1-45 wt.% of a second ceramic powder, the total amount of said first and second ceramic powders being 20-50 wt.%, said first ceramic powder consisting of 68-75 wt.% ZnO, 23-28 wt.% SiO 2 and up to 8 wt.% Al 2 O 3 , and said second ceramic powder consisting of 98-99.9 wt.% SnO 2 and 0.1-2 wt.% ZnO.
Claim 2
Dependent Claim
140 words
A low temperature sealing composition for a seal of high mechanical strength between two alumina ceramic parts to form a sealed package having a shearing strength of at least 310 kg, the sealing composition having a sealing temperature of no more than 450° C. and consisting essentially of a mixture of 50-80 wt.% of a vitreous solder glass powder of PbO-B 2 O 3 system having a deformation point of 350° C. or less, 1-35 wt.% of a first ceramic powder and 1-45 wt.% of a second ceramic powder, the total amount of said first and second ceramic powders being 20-50 wt.%, said first ceramic powder consisting of 68-75 wt.% ZnO, 23-28 wt.% SiO 2 and up to 8 wt.% Al 2 O 3 , and said second ceramic powder consisting of 98-99.9 wt.% SnO 2 and 0.1-2 wt.% ZnO.
Claim 3
Dependent Claim
48 words
A low temperature sealing composition as claimed in claim 1, wherein said solder glass powder consists of 80-86 wt.% PbO, 11.0-13.0 wt.% B 2 O 3 , 0.5-2.0 wt.% SiO 2 , 0-5 wt.% ZnO, 0-2 wt.% Al 2 O 3 , and 0-2 wt.% F 2 .
Claim 4
Dependent Claim
25 words
A low temperature sealing composition as claimed in claim 1, wherein said solder glass powder is fine enough to pass a standard 150 mesh screen.
Claim 5
Dependent Claim
25 words
A low temperature sealing composition as claimed in claim 1, wherein said first ceramic powder is fine enough to pass a standard 325 mesh screen.
Claim 6
Dependent Claim
25 words
A low temperature sealing composition as claimed in claim 1, wherein said second ceramic powder is fine enough to pass a standard 325 mesh screen.
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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) | 1988-08-26 | 1989-02-25 | 1989-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-26 | 1993-02-25 | 1993-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-26 | 1997-02-25 | 1997-08-27 | $7700.00 | Window Closed / Lapsed |