Etching methods for a magnetic memory cell stack
US6821907B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Mar 6, 2002 |
| Grant date | Nov 23, 2004 |
| Priority date | — |
| Expiry date | Mar 13, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/308
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A method and apparatus for etching a magnetic memory cell stack are described. More particularly, HCl is used as a main etchant gas for etching a magnetic memory cell stack. HCl is used in part to reduce corrosion and improve selectivity. Additionally, use of an amorphous carbon or hydrocarbon based polymer resin for a hard mask is described, as well as a post-etch passivation with a water rinse, a water vapor plasma treatment or an ammonia plasma treatment. Moreover, in an embodiment, a diffusion barrier layer dispose most of the magnetic memory cell stack is etched with hydrogen and fluorine containing gas in a separate process chambers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.