Endpoint detection in low open area and/or high aspect ratio etch applications
US12046522B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 2022 |
| Grant date | Jul 23, 2024 |
| Priority date | — |
| Expiry date | Sep 30, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/334
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed herein is a method for determining the endpoint of an etch operation used for forming high aspect ratio features and/or over low open area (<1%) on a substrate in a processing chamber. The method begins by obtaining a reference emission curve. An etch operation is performed on a patterned substrate. A plasma optical emission intensity is measured for each of the etch cycles. A differential curve between the reference emission and the plasma optical emissions is calculated. And endpoint is determined for the etch operation on the first substrate based on an inflection point detection or other unique features through pattern recognition in the differential curve for stopping the etch of the first substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.