Pellicle replacement in EUV mask flow
US10401724B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2017 |
| Grant date | Sep 3, 2019 |
| Priority date | — |
| Expiry date | Mar 17, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70741
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical mask has a first pellicle attached. The optical mask is inspected with the first pellicle in place using first wavelengths of electromagnetic radiation. The first pellicle is replaced with a second pellicle. The first pellicle only allows the first wavelengths of electromagnetic radiation to pass, and the second pellicle allows second wavelengths that are shorter than the first wavelengths to pass. A photoresist is exposed using the optical mask with the second pellicle in place. The second pellicle is replaced with the first pellicle. The optical mask is again inspected with the first pellicle in place using the first wavelengths of electromagnetic radiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.