Method of selectively removing a region formed of silicon oxide and plasma processing apparatus
US9502537B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2014 |
| Grant date | Nov 22, 2016 |
| Priority date | — |
| Expiry date | Aug 27, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Provided is a method of selectively removing a first region from a workpiece which includes the first region formed of silicon oxide and a second region formed of silicon. The method performs a plurality of sequences. Each sequence includes: forming a denatured region by generating plasma of a processing gas that contains hydrogen, nitrogen, and fluorine within a processing container that accommodates the workpiece so as to denature a portion of the first region, and removing the denatured region within the processing container. In addition, a sequence subsequent to a predetermined number of sequences after a first sequence among the plurality of sequences further includes exposing the workpiece to plasma of a reducing gas which is generated within the processing container, prior to the forming of the denatured region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.