Fluorocarbon molecules for high aspect ratio oxide etch
US10381240B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 2016 |
| Grant date | Aug 13, 2019 |
| Priority date | — |
| Expiry date | Sep 14, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2601/04
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Etching gases are disclosed for plasma etching channel holes, gate trenches, staircase contacts, capacitor holes, contact holes, etc., in Si-containing layers on a substrate and plasma etching methods of using the same. The etching gases are trans-1,1,1,4,4,4-hexafluoro-2-butene; cis-1,1,1,4,4,4-hexafluoro-2-butene; hexafluoroisobutene; hexafluorocyclobutane (trans-1,1,2,2,3,4); pentafluorocyclobutane (1,1,2,2,3-); tetrafluorocyclobutane (1,1,2,2-); or hexafluorocyclobutane (cis-1,1,2,2,3,4). The etching gases may provide improved selectivity between the Si-containing layers and mask material, less damage to channel region, a straight vertical profile, and reduced bowing in pattern high aspect ratio structures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.