Microwave dielectric ceramic composition
US5310710A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 1992 |
| Grant date | May 10, 1994 |
| Priority date | — |
| Expiry date | Apr 6, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/4686
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A dielectric ceramic composition which comprises a composition represented by xBaO.yNd.sub.2 O.sub.3.zTiO.sub.2 (where 8.5.ltoreq.x.ltoreq.20, 5.ltoreq.y.ltoreq.23, 62.ltoreq.z.ltoreq.85, and x+y+z=100), Y.sub.2 O.sub.3 in an amount not more than 15 wt % of the amount of said composition, and Al.sub.2 O.sub.3 in an amount not more than 2 wt % of the total amount of the principal components BaO, Nd.sub.2 O.sub.3, TiO.sub.2, and Y.sub.2 O.sub.3. And a relative permittivity .epsilon.r of the dielectric ceramic is not less than 59, its dielectric loss (tan .delta.) is 3.times.10.sup.-4 .about.8.times.10.sup.-4 (2.7 GHz), and its temperature coefficient of resonant frequency .tau.f may be -30.about.+10 ppm/.degree.C. This microwave ceramic dielectric will be used for dielectric resonators in the microwave frequency region, microwave IC substrates, and impedance matching of microwave circuits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.