Method for forming via contact hole in a semiconductor device
US5925577A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 1997 |
| Grant date | Jul 20, 1999 |
| Priority date | — |
| Expiry date | Oct 3, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/963
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of plasma etching photoresist and sidewall polymer with an etch gas mixture comprising a fluorine containing gas (CF.sub.4 or NF.sub.3) and H.sub.2 O demonstrating very aggressive ashrate of photoresist but maintains an exceptionally low etch rate for titanium nitride and other metals is provided. The very low TiN etch rate permits the inventive method to effectively breakdown sidewall polymer without removing any significant amount of these metals. The invention is particularly suited for stripping sidewall polymer from etched via holes and from etched metal lines. Vias fabricated with this technique exhibit exceptionally low resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.