The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 17, 2012
Filed:
Jun. 20, 2006
Guenther Hans Derra, Aachen, DE;
Thomas Kruecken, Aachen, DE;
Christof Metzmacher, Aachen, DE;
Achim Weber, Aachen, DE;
Peter Zink, Aachen, DE;
Guenther Hans Derra, Aachen, DE;
Thomas Kruecken, Aachen, DE;
Christof Metzmacher, Aachen, DE;
Achim Weber, Aachen, DE;
Peter Zink, Aachen, DE;
Kninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
The present invention relates to a method of cleaning and after treatment of optical surfaces in an irradiation unit, said irradiation unit comprising a radiation source () emitting EUV-radiation and/or soft X-rays, a first volume () following said radiation source () and containing first optical components () with said optical surfaces, and a second volume () following said first volume () and containing second optical components (). The method comprises at least one cleaning step in which a first gas or gas mixture is brought into contact with said optical surfaces, thereby forming volatile compounds with contaminations deposited on said optical surfaces, wherein said compounds are pumped out of the first volume () together with the first gas or gas mixture. In an after treatment step following said cleaning step the radiation source () is operated once or several times in order to release residues of the cleaning step from the optical surfaces by irradiating said optical surfaces with said EUV-radiation or soft X-rays while the first volume () is separated from the second volume (), wherein said released residues are pumped out of the first volume (). With this method an improved cleaning result is achieved.