Self-aligned contacts for semiconductor device
US6133153A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1998 |
| Grant date | Oct 17, 2000 |
| Priority date | — |
| Expiry date | Mar 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A plasma, formed from a mixture of C.sub.4 F.sub.8 and CH.sub.2 F.sub.2, is used to etch a self-aligned contact, the self-aligned contact being an opening in the oxide layer, the opening being aligned with an opening in an underlying nitride layer and extending to a substrate underlying the nitride. The mixture of C.sub.4 F.sub.8 and CH.sub.2 F.sub.2 provides a high ratio of oxide etch rate to nitride etch rate so that the etching is completed without substantially damaging the nitride layer. For thicker oxide layers a preliminary etch step using C.sub.2 F.sub.6 and C.sub.2 HF.sub.5 may be performed prior to using the mixture of C.sub.4 F.sub.8 and CH.sub.2 F.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.