US4780435A
Expired / Lapsed
US
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Dielectric ceramic compositions with linear temperature coefficient characteristics and low dissipation factors
Assignee: Deutsches Zentrum für Luft- und Raumfahrt eV
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Filing: 1987-04-15
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Granted: 1988-10-25
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Expires: 2007-04-15
Abstract
Abstract Ceramic dielectric compositions which have dielectric constants (K) of 60-140, dissipation factors (DF) of less than 0.1 percent, and temperature coefficient characteristics (TCC) of -20 ppm to -1000 ppm/ DEG C.
Inventors
- 👤 Michael S. H. Chu
- 👤 Julie E. Carminati
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:27
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/50; C04B35/01; C04B35/46; C04B35/462
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
89 words
A sinterable ceramic composition consisting essentially of about 40.2 to 98.34 weight % of a precursor material consisting essentially of about 48.49 weight % neodymium oxide, about 33.71 weight % titanium oxide, about 14.39 weight percent barium carbonate, about 1.42 weight % zirconium oxide, about 1.48 weight % silicon dioxide, and about 0.51 weight % calcium titanate, and a second material consisting essentially of about 0 to 57.51 weight % strontium titanate, about 1.27 to 3.14 weight % niobium pentoxide and about 0.23 to 0.43 weight % cobalt oxide.
Claim 2
Dependent Claim
89 words
A sinterable ceramic composition consisting essentially of about 40.2 to 98.34 weight % of a precursor material consisting essentially of about 48.49 weight % neodymium oxide, about 33.71 weight % titanium oxide, about 14.39 weight percent barium carbonate, about 1.42 weight % zirconium oxide, about 1.48 weight % silicon dioxide, and about 0.51 weight % calcium titanate, and a second material consisting essentially of about 0 to 57.51 weight % strontium titanate, about 1.27 to 3.14 weight % niobium pentoxide and about 0.23 to 0.43 weight % cobalt oxide.
Claim 3
Dependent Claim
43 words
The ceramic composition of claim 1, wherein the neodymium oxide has a purity of greater than 99.5%, the cobalt oxide has a purity of 70% to 74% of metallic cobalt and the balance of the components have a purity of at least 99%.
Claim 4
Dependent Claim
58 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of 1.40 and -1000 ppm/°C. TCC characteristics consisting essentially of about 40.21 weight percent of the ceramic precursor material, about 56.40 weight percent of strontium titanate, about 3.14 weight percent of niobium pentoxide, and about 0.26 weight percent of cobalt oxide.
Claim 5
Dependent Claim
55 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of 1.22 and -900 ppm/°C. TCC characteristics, consisting essentially of about 43.57 weight percent of the ceramic precursor material, about 53.13 weight percent strontium titanate, about 3.04 weight percent niobium pentoxide and about 0.26 weight percent cobalt oxide.
Claim 6
Dependent Claim
59 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of about 0.61 and -580 ppm/°C. TCC characteristics consisting essentially of about 60.49 weight percent of the ceramic precursor material, about 36.66 weight percent of strontium titanate, about 2.58 weight percent of niobium pentoxide, and about 0.27 weight percent of cobalt oxide.
Claim 7
Dependent Claim
59 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of about 0.40 and -430 ppm/°C. TCC characteristics consisting essentially of about 69.85 weight percent of the ceramic precursor material, about 27.64 weight percent of strontium titanate, about 2.24 weight percent of niobium pentoxide and about 0.27 weight percent of cobalt oxide.
Claim 8
Dependent Claim
59 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of about 0.24 and -275 ppm/°C. TCC characteristics consisting essentially of about 78.63 weight percent of the ceramic precursor material, about 19.11 weight percent of strontium titanate, about 1.98 weight percent of niobium pentoxide and about 0.28 weight percent of cobalt oxide.
Claim 9
Dependent Claim
59 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of about 0.18 and -210 ppm/°C. TCC characteristics consisting essentially of about 82.99 weight percent of the ceramic precursor material, about 14.89 weight percent of strontium titanate, about 1.84 weight percent of niobium pentoxide and about 0.28 weight percent of cobalt oxide.
Claim 10
Dependent Claim
59 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of about 0.12 with -110 ppm/°C. TCC characteristics consisting essentially of about 87.39 weight percent of the ceramic precursor material, about 10.60 weight percent of strontium titanate, about 1.73 weight percent of niobium pentoxide and about 0.28 weight percent of cobalt oxide.
Claim 11
Dependent Claim
51 words
A ceramic composition according to claims 1 or 2 having a strontium titanate to precursor weight ratio of 0 and -40 ppm/°C. TCC characteristics consisting essentially of about 98.34 weight percent of the ceramic precursor material, about 1.37 weight percent of niobium pentoxide and about 0.29 weight percent of cobalt oxide.
Claim 12
Dependent Claim
34 words
A multilayer ceramic capacitor consisting essentially of the compositions of any of the preceding claims cofired with electrodes comprising at least one metal selected from the group consisting of silver, gold, platinum, and palladium.
References Cited (Backward Citations)
JPS5368899A
Cited
JPS53114812A
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US4338403A
Cited
US4468472A
Cited
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Cited
US4506026A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-25 | 1992-04-25 | 1992-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-25 | 1996-04-25 | 1996-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-25 | 2000-04-25 | 2000-10-25 | $7700.00 | Window Closed / Lapsed |