Anisotropic and selective nitride etch process for high aspect ratio features in high density plasma
US6051504A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 1997 |
| Grant date | Apr 18, 2000 |
| Priority date | — |
| Expiry date | Aug 15, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for etching silicon nitride from a multilayer structure which uses an etchant gas including a fluorocarbon gas, a hydrogen source, and a weak oxidant. A power source, such as an RF power source, is applied to the structure to control the directionality of the high density plasma formed by exciting the etchant gas. The power source that controls the directionality of the plasma is decoupled from the power source used to excite the etchant gas. The fluorocarbon gas is selected from CF.sub.4, C.sub.2 F.sub.6, and C.sub.3 F.sub.8 ; the hydrogen source is selected from CH.sub.2 F.sub.2, CH.sub.3 F, and H.sub.2 ; and the weak oxidant is selected from CO, CO.sub.2, and O.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.