Plasma etching techniques
US11424120B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 2021 |
| Grant date | Aug 23, 2022 |
| Priority date | — |
| Expiry date | Jan 22, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D30/6757
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In certain embodiments, a method of processing a semiconductor substrate includes positioning a semiconductor substrate in a plasma chamber of a plasma tool. The semiconductor substrate includes a film stack that includes silicon layers and germanium-containing layers in an alternating stacked arrangement, with at least two silicon layers and at least two germanium-containing layers. The method includes exposing, in a first plasma step executed in the plasma chamber, the film stack to a first plasma. The first plasma is generated from first gases that include nitrogen gas, hydrogen gas, and fluorine gas. The method includes exposing, in a second plasma step executed in the plasma chamber, the film stack to a second plasma. The second plasma is generated from second gases comprising fluorine gas and oxygen gas. The second plasma selectively etches the silicon layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.