Isotropic atomic layer etch for silicon oxides using no activation
US9425041B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 6, 2015 |
| Grant date | Aug 23, 2016 |
| Priority date | — |
| Expiry date | Jan 6, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/334
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods for controlled isotropic etching of layers of silicon oxide and germanium oxide with atomic scale fidelity are provided. The methods make use of NO activation of an oxide surface. Once activated, a fluorine-containing gas or vapor etches the activated surface. Etching is self-limiting as once the activated surface is removed, etching stops since the fluorine species does not spontaneously react with the un-activated oxide surface. These methods may be used in interconnect pre-clean applications, gate dielectric processing, manufacturing of memory devices, or any other applications where accurate removal of one or multiple atomic layers of material is desired.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.