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. 06, 2009
Filed:
Dec. 16, 2005
Mandeep Singh, Delft, NL;
Mandeep Singh, Delft, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
A lithographic apparatus that includes at least one optical surface exposed to a radiation beam, and a surface plasmon resonance measurement apparatus adjacent the optical surface that is configured to detect contamination of at least one optical surface of the lithographic apparatus. The measurement apparatus is located near or in close proximity to the optical surface to as to emulate and determine possible contamination without interfering with the radiation beam used to expose the optical surface. A radiation source for the measurement apparatus is configured to provide a probing beam of radiation having an angle of incidence. By measuring the surface plasmons and/or the angles of incidence of a reference optical surface in the measurement apparatus, contamination deposited on an optical surface in the lithographic apparatus may be inferred.