Delicate dry clean
US8895449B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 14, 2013 |
| Grant date | Nov 25, 2014 |
| Priority date | — |
| Expiry date | Aug 14, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of selectively removing fluorocarbon layers from overlying low-k dielectric material is described. These protective plasma treatments (PPT) are delicate alternatives to traditional post-etch treatments (PET). The method includes sequential exposure to (1) a local plasma formed from a silicon-fluorine precursor followed by (2) an exposure to plasma effluents formed in a remote plasma from a fluorine-containing precursor. The remote plasma etch (2) has been found to be highly selective of the residual material following the local plasma silicon-fluorine exposure. The sequential process (1)-(2) avoids exposing the low-k dielectric material to oxygen which would undesirably increase its dielectric constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.