Multilayer ceramic substrate with circuit patterns
US4795670A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 1987 |
| Grant date | Jan 3, 1989 |
| Priority date | — |
| Expiry date | May 8, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24926
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A multilayer ceramic substrate with multilayered circuit patterns, the improvement in which internal conductors for wiring are formed by a Ag base conductive materials capable of being co-fired with multilayered green ceramic substrate sheets in an oxidizing atmosphere and external conductors electrically connected with the internal conductors are formed by a Cu base conductive material, the external Cu conductors being formed in such a manner so that a liquid phase of Cu-Ag is not formed at the interface of the Cu conductor and the Ag conductor. Further high reliable resistors of RuO.sub.2 or Bi.sub.2 Ru.sub.2 O.sub.7 type may be integrally formed onto and/or inside the substrate. In such an arrangement, problems or difficulties caused due to Ag migration, incomplete binder removal, solder leaching, etc., are eliminated and thereby there can be a multilayer substrate with a high reliability and a high pattern precision.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.