Method for etching a dielectric layer formed upon a barrier layer
US6693042B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 2000 |
| Grant date | Feb 17, 2004 |
| Priority date | — |
| Expiry date | Feb 5, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for etching a dielectric layer formed upon a barrier layer with an etch chemistry including CxHyFz, in which x≧2, y≧2, and z≧2 is provided. Such an etch chemistry may be selective to the barrier layer. For example, the etch chemistry may have a dielectric layer:barrier layer selectivity of at least approximately 20:1, but may range from approximately 20:1 to approximately 50:1. Therefore, etching a dielectric layer with such an etch chemistry may terminate upon exposing an upper surface of the barrier layer. As such, a thickness of a barrier layer used to protect an underlying layer may be reduced to, for example, approximately 100 angstroms to approximately 150 angstroms. In addition, critical dimensions of contact openings formed with such an etch chemistry may be substantially uniform across a wafer. Furthermore, critical dimensions of contact openings formed with such an etch chemistry may be uniform from wafer to wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.