System and method for cleaning optical surfaces of an extreme ultraviolet optical system
US10953441B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2013 |
| Grant date | Mar 23, 2021 |
| Priority date | — |
| Expiry date | Jul 10, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B19/0095
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a local clean microenvironment near optical surfaces of an extreme ultraviolet (EUV) optical assembly maintained in a vacuum process chamber and configured for EUV lithography, metrology, or inspection. The system includes one or more EUV optical assemblies including at least one optical element with an optical surface, a supply of cleaning gas stored remotely from the one or more optical assemblies and a gas delivery unit comprising: a plenum chamber, one or more gas delivery lines connecting the supply of gas to the plenum chamber, one or more delivery nozzles configured to direct cleaning gas from the plenum chamber to a portion of the EUV assembly, and one or more collection nozzles for removing gas from the EUV optical assembly and the vacuum process chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.