Metal-ceramic composite substrate
US6071592A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 1997 |
| Grant date | Jun 6, 2000 |
| Priority date | — |
| Expiry date | Jul 23, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249967
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A metal-ceramic composite circuit substrate having a ceramic substrate and a metal plate joined to at least one main surface of the ceramic substrate, the rate of voids formed on at least a joint surface at a semiconductor mounting portion of the metal plate per unit surface area being not more than 1.49%. The diameter of void formed on at least the joint surface at a semiconductor mounting portion of the metal plate is not larger than 0.7 mm. The surface undulation of the ceramic substrate is not more than 15 .mu.m/20 mm measured by a surface roughness tester in case that the ceramic substrate is joined directly to the metal plate. The metal plate is joined to the ceramic substrate through a brazing material containing at least one active metal selected from a group consisting of Ti, Zr, Hf and Nb. The ceramic substrate is at least one kind of ceramic substrate selected from a group consisting of Al.sub.2 O.sub.3, AlN, BeO, SiC, Si.sub.3 N.sub.4 and ZrO.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.