Systems and methods to control critical dimension (CD) shrink ratio through radio frequency (RF) pulsing
US11495436B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 2021 |
| Grant date | Nov 8, 2022 |
| Priority date | — |
| Expiry date | Feb 16, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/334
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Systems and methods are provided herein for etch features on a substrate, while maintaining a near-unity critical dimension (CD) shrink ratio. The features etched may include, but are not limited to contacts, vias, etc. More specifically, the techniques described herein use a pulsed plasma to control the polymer build-up ratio between the major CD and minor CD of the feature, and thus, control the CD shrink ratio when etching features having substantially different major and minor dimensions. The CD shrink ratio is controlled by selecting or adjusting one or more operational parameters (e.g., duty cycle, RF power, etch chemistry, etc.) of the plasma etch process(es) to control the amount of polymer build-up at the major and minor dimensions of the feature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.