Saving ion-damaged spacers
US9721789B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2016 |
| Grant date | Aug 1, 2017 |
| Priority date | — |
| Expiry date | Oct 24, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/6715
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods of selectively removing silicon oxide are described. Exposed portions of silicon oxide and spacer material may both be present on a patterned substrate. The silicon oxide may be a native oxide formed on silicon by exposure to atmosphere. The exposed portion of spacer material may have been etched back using reactive ion etching (RIE). A portion of the exposed spacer material may have residual damage from the reactive ion etching. A self-assembled monolayer (SAM) is selectively deposited over the damaged portion of spacer material but not on the exposed silicon oxide or undamaged portions of spacer material. A subsequent gas-phase etch may then be used to selectively remove silicon oxide but not the damaged portion of the spacer material because the SAM has been found to not only preferentially adsorb on the damaged spacer but also to halt the etch rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.