Method of etching a three-dimensional dielectric layer
US10573529B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 2018 |
| Grant date | Feb 25, 2020 |
| Priority date | — |
| Expiry date | Dec 27, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D30/0241
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for etching a dielectric layer covering at least one top and at least one flank of a semi-conductive material-based structure is provided, including a plurality of sequences, each including successive steps of: a first etching of the layer by plasma using a chemistry including at least a first fluorine-based compound and a second compound chosen from SiwCl(2w+2) and SiwF(2w+2), w, x, y, and z being whole numbers, and oxygen, the first etching: interrupting before complete consumption of the dielectric layer thickness on the flank and after complete consumption of the thickness on the top, and forming a first protective layer on the top and a second protective layer on the flank; and a second etching fully removing the second layer while conserving a portion of the first layer thickness, each sequence being repeated until complete removal of the dielectric layer on the flank.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.