Contact structure for reliable metallic interconnection
US6696757B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2002 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | Jul 18, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A metallurgical interconnection for electronic devices is described, wherein the interconnection has first and second interconnection metals. The first metal is shaped to enlarge the contact area, thus providing maximum mechanical interconnection strength, and to stop nascent cracks, which propagate in the interconnection. Preferred shapes include castellation and corrugation. The castellation may include metal protrusions, which create wall-like obstacles in the interconnection zones of highest thermomechanical stress, whereby propagating cracks are stopped. The surface of the first metal has an affinity to form metallurgical contacts. The second metal is capable of reflowing. The first metal is preferably copper, and the second metal tin or a tin alloy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.