Gold metallization in semiconductor devices
US4417387A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 15, 1981 |
| Grant date | Nov 29, 1983 |
| Priority date | — |
| Expiry date | Apr 15, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Gold is preferred as the conductor material in a metallization layer of a semiconductor device because of its high conductivity and freedom from electromigration effects but gold is inclined to diffuse into the semiconductor substrate typically silicon, so degrading the p-n junction characteristics within the semiconductor substrate and rendering the device inoperative. Previously this problem has been overcome by placing a protective barrier layer of titanium between the gold layer and the substrate. The gold/titanium interface is subject to corrosion and this corrosion adjacent the substrate containing the active areas of the device also leads to failure of the device. This is prevented by covering the gold metallization layer of the device on its top, bottom and side surfaces with titanium. This prevents the diffusion of the gold into any other layer of the semiconductor device above or below it and there is no gold/titanium interface exposed adjacent any active area of the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.