Impregnation of aluminum interconnects with copper
US4489482A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1983 |
| Grant date | Dec 25, 1984 |
| Priority date | — |
| Expiry date | Jun 6, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76886
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for impregnating copper into aluminum interconnect lines on a semiconductor device is disclosed. In a first embodiment, an interconnect pattern is formed on an aluminum layer by etching while the aluminum is substantially free from copper, and the copper is thereafter introduced to the formed interconnect lines. In a second embodiment, copper is introduced to the aluminum layer prior to formation of the desired interconnect pattern. The copper-rich layer is removed from the areas to be etched prior to etching. The method facilitates chlorine plasma etching of the aluminum which is inhibited by the presence of copper. The method is also useful with various wet etching processes where the formation of a copper-rich layer is found to stabilize the aluminum layer during subsequent processing .
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.