Dielectric material with low temperature coefficient and high quality
US6121174A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1997 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Sep 26, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/0306
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A dielectric material is disclosed which has a small absolute value of the temperature coefficient of resonance frequency and a high coefficient of unloaded quality. Also disclosed are a process for producing the dielectric material and multilayer and other circuit boards containing the dielectric material. The dielectric material is a highly densified material having a water absorption lower than 0.1%, which is obtained by mixing 95.5 to 99.5 percent by weight mixture of a glass frit and a strontium compound with 0.5 to 4.5 percent by weight titanium dioxide, compacting the resultant mixture, and sintering the compact at a relatively low temperature around 930.degree. C. This dielectric material is a glass ceramic containing strontium anorthite (SrAl.sub.2 Si.sub.2 O.sub.8) as the main crystalline phase, and may contain the TiO.sub.2, which remains unchanged after sintering. The absolute value of the temperature coefficient of resonance frequency of the dielectric material is 20 ppm/.degree. C. or lower, preferably 10 ppm/.degree. C. or lower, more preferably 5 ppm/.degree. C. or lower. The product of the unloaded quality coefficient and resonance frequency is 1,800 GHz or larger,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.