Power modulation for etching high aspect ratio features
US10410873B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 2017 |
| Grant date | Sep 10, 2019 |
| Priority date | — |
| Expiry date | Jan 20, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3065
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of etching a substrate is described. The method includes disposing a substrate having a surface exposing a first material and a second material in a processing space of a plasma processing system, and performing a modulated plasma etching process to selectively remove the first material at a rate greater than removing the second material. The modulated plasma etching process comprises a power modulation cycle having sequential power application steps that includes: applying a radio frequency (RF) signal to the plasma processing system at a first power level, applying the RF signal to the plasma processing system at a second power level, and applying the RF signal to the plasma processing system at a third power level. Thereafter, the power modulation cycle is repeated at least one more cycle, wherein each modulation cycle includes a modulation time period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.