Etch suppression with germanium
US9576809B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 2014 |
| Grant date | Feb 21, 2017 |
| Priority date | — |
| Expiry date | Feb 2, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/3346
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Methods of selectively etching silicon relative to silicon germanium are described. The methods include a remote plasma etch using plasma effluents formed from a fluorine-containing precursor and a hydrogen-containing precursor. Plasma effluents from the remote plasma are flowed into a substrate processing region where the plasma effluents react with the silicon. The plasmas effluents react with exposed surfaces and selectively remove silicon while very slowly removing other exposed materials. The methods are useful for removing Si(1-X)GeX faster than Si(1-Y)GeY, for X<Y. In some embodiments, the silicon germanium etch selectivity results partly from the presence of an ion suppression element positioned between the remote plasma and the substrate processing region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.