Microwave dielectric ceramic composition
US6331499A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 2001 |
| Grant date | Dec 18, 2001 |
| Priority date | — |
| Expiry date | Feb 9, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2235/6585
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A microwave dielectric ceramic composition exhibiting excellent relative permitting (.di-elect cons.) and high Qf-value, enabling the temperature coefficient of resonance frequency to be easily adjusted, and being best suited for a filter having cavities made of, e.g., iron or copper exhibiting a large temperature coefficient of resonance frequency. The ceramic is of a BaO--TiO.sub.2 --Nd.sub.2 O.sub.3 --Sm.sub.2 O.sub.3 ceramic, type wherein Nd.sub.2 O.sub.3 is partly substituted by Bi.sub.2 O.sub.3, Nd.sub.2 O.sub.3 is Partly substituted by Ln.sub.2 O.sub.3 (where Ln is La, Ce or Pr) and, the above substituted Ln.sub.2 O.sub.3 is partly substituted by EU.sub.2 O.sub.3 to improve the properties so that .di-elect cons. is 82.5 to 92.5, Qf is 6000 to 7300 GHz and .tau.f is 10-20 ppm/.degree. C. This makes it possible to impart favorable electric characteristics to resonance cavities of various materials and sizes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.