Interconnect structures using group VIII metals
US5563449A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jan 19, 1995 |
| Grant date | Oct 8, 1996 |
| Priority date | — |
| Expiry date | Jan 19, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A multiple layer interconnect structure for a semiconductor chip includes a graded transition layer of tungsten and a Group VIII metal, such as palladium, platinum or nickel (Pd, Pt or Ni) which allows formation of a Group VIII metal interconnect on a conventional pad of Al or Al alloy. The graded transition layer is interfaced between a thin adhesion layer on the pad and the Group VIII metal interconnect, and is approximately 100% tungsten where it interfaces the adhesion layer and approximately 100% Group VIII metal where it interfaces the interconnect layer. The tungsten in the graded transition layer acts as a solder barrier and the Group VIII metal interconnect is compatible with the silicon substrate so that packaging processing steps, including lead soldering, can be carried out, and the chip electrically tested, in the semiconductor fabrication facility.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.