Atomic layer etch (ALE) of tungsten or other metal layers
US11189499B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2020 |
| Grant date | Nov 30, 2021 |
| Priority date | — |
| Expiry date | Feb 27, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/32136
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods for the atomic layer etch (ALE) of tungsten or other metal layers are disclosed that use in part sequential oxidation and reduction of tungsten/metal layers to achieve target etch parameters. For one embodiment, a metal layer is first oxidized to form a metal oxide layer and an underlying metal layer. The metal oxide layer is then reduced to form a surface metal layer and an underlying metal oxide layer. The surface metal layer is then removed to leave the underlying metal oxide layer and the underlying metal layer. Further, the oxidizing, reducing, and removing processes can be repeated to achieve a target etch depth. In addition, a target etch rate can also achieved for each process cycle of oxidizing, reducing, and removing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.