Layer-by-layer etching of poly-granular metal-based materials for semiconductor structures
US11270893B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2019 |
| Grant date | Mar 8, 2022 |
| Priority date | — |
| Expiry date | Dec 5, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76856
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for etching a poly-granular metal-based film includes providing a flow of a background gas in a plasma etching chamber containing a semiconductor structure including the poly-granular metal-based film formed over a substrate with a mask patterned over the poly-granular metal-based film. The method also includes applying a source power to generate a background plasma from the background gas, and providing a flow of a modifying gas while maintaining the flow of the background gas to generate a modifying plasma that produces a surface modification region with a substantially uniform depth in the top surface of the poly-granular metal-based film exposed by the mask. The method further includes stopping the flow of the modifying gas while maintaining the flow of the background gas, and applying a biasing power to the substrate to remove the surface modification region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.