Method of forming a self-aligned copper diffusion barrier in vias
US5985762A · kind A · utility
197Cited by
13References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 19, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | May 19, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76877
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A copper diffusion barrier is formed on the side walls of vias connected to copper conductors to prevent copper diffusion into inter-level dielectric. A thin film of copper diffusion barrier material is deposited on the wafer post via etch. A sputter etch is performed to remove barrier material from the base of via and to remove copper oxide from the copper conductor. The barrier material is not removed from the sidewall during the sputter etch. Thus, a barrier to re-deposited copper is formed on the via sidewalls to prevent copper poisoning of the dielectric.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.