Cleaning method, apparatus and cleaning system
US7671347B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 10, 2006 |
| Grant date | Mar 2, 2010 |
| Priority date | — |
| Expiry date | Feb 22, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70925
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method to clean optical elements of an apparatus, the apparatus being configured to project a beam of radiation onto a target portion of a substrate, the apparatus comprising a plurality of optical elements arranged in sequence in the path of the radiation beam, wherein the cleaning method comprises: cleaning one or more second optical elements of the sequence, which receive one or more relatively low second radiation doses during operation of the apparatus, utilizing cumulatively shorter cleaning periods than one or more first optical elements of the sequence that receive one or more first radiation doses during operation of the apparatus, a second radiation dose being lower than each relatively high first radiation dose.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.