Method to prevent pattern collapse in features etched in sulfur dioxide-containing plasmas
US6849389B2 · kind B2 · utility
7Cited by
9References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 12, 2001 |
| Grant date | Feb 1, 2005 |
| Priority date | — |
| Expiry date | Oct 7, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/094
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Disclosed is an in-situ process that prevents pattern collapse from occurring after they have been etched in S02-containing plasmas. The developed process involving treating the etched wafer to another plasma comprising of a chemically reducing gas such as H2. This treatment chemically reduces the hygroscopic sulfites/sulfates left on the surface after the main etch step. The lower sulfite/sulfate concentration on the wafer translates into considerably less moisture pick up and prevents high aspect ratio feature collapse.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.