Atomic layer etching of silicon nitride
US10079154B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2017 |
| Grant date | Sep 18, 2018 |
| Priority date | — |
| Expiry date | Mar 20, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for selectively etching SiN with respect to SiO or SiGe or Si of a structure is provided comprising providing a plurality of cycles of atomic layer etching. Each cycle comprises a fluorinated polymer deposition phase comprising flowing a fluorinated polymer deposition gas comprising a hydrofluorocarbon gas into the plasma processing chamber, forming the fluorinated polymer deposition gas into a plasma, which deposits a hydrofluorocarbon polymer layer on the structure, and stopping the flow of the fluorinated polymer deposition gas into the plasma processing chamber and an activation phase comprising flowing an activation gas comprising at least one of NH3 or H2 into the plasma processing chamber, forming the activation gas into a plasma, wherein plasma components from NH3 or H2 cause SiN to be selectively etched with respect to SiO or SiGe or Si, and stopping the flow of the activation gas into the plasma processing chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.