Polysilicon etch with high selectivity
US8916477B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 2013 |
| Grant date | Dec 23, 2014 |
| Priority date | — |
| Expiry date | Jun 12, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P80/30
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Provided are methods and systems for removing polysilicon on a wafer. A wafer can include a polysilicon layer and an exposed nitride and/or oxide structure. An etchant with a hydrogen-based species, such as hydrogen gas, and a fluorine-based species, such as nitrogen trifluoride, can be introduced. The hydrogen-based species and the fluorine-based species can be activated with a remote plasma source. The layer of polysilicon on the wafer can be removed at a selectivity over the exposed nitride and/or oxide structure that is greater than about 500:1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.