Cobalt-containing material removal
US9947549B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2016 |
| Grant date | Apr 17, 2018 |
| Priority date | — |
| Expiry date | Oct 24, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/334
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods are described herein for etching cobalt films which are difficult to volatize. The methods include exposing a cobalt film to a bromine or chlorine-containing precursor with a concurrent local plasma which applies a bias to the impinging etchants. Cobalt halide is formed on the surface at the same time an amorphized cobalt layer is formed near the surface. A carbon-and-nitrogen-containing precursor is later delivered to the substrate processing region to form volatile cobalt complexes which desorb from the surface of the cobalt film. Cobalt may be selectively removed. The concurrent production of cobalt halide and amorphized regions was found to markedly increase the overall etch rate and markedly improve surface smoothness upon exposure to the carbon-and-nitrogen-containing precursor. All the recited steps may now be performed in the same substrate processing chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.