Selective atomic layer etching
US10847375B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2018 |
| Grant date | Nov 24, 2020 |
| Priority date | — |
| Expiry date | Sep 29, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/3346
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for selectively etching a dielectric layer with respect to an epitaxial layer or metal-based hardmask is provided. The method comprises performing a plurality of cycles. Each cycle comprises a deposition phase and an activation phase. The deposition phase comprises flowing a deposition gas, wherein the deposition gas comprises helium and a hydrofluorocarbon or fluorocarbon, forming the deposition gas into a plasma to effect a fluorinated polymer deposition, and stopping the flow of the deposition gas. The activation phase comprises flowing an activation gas comprising an ion bombardment gas, forming the activation gas into a plasma, providing an activation bias to cause ion bombardment of the fluorinated polymer deposition, wherein the ion bombardment activates fluorine from the fluorinated polymer deposition to etch the dielectric layer, and stopping the flow of the activation gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.