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:
Oct. 26, 2010
Filed:
Dec. 22, 2008
Todd R. Downey, Monroe, CT (US);
Todd R. Downey, Monroe, CT (US);
ASML Holding N.V., Veldhoven, NL;
Abstract
Angular deviation of illumination beam is measured with high accuracy for an expanded continuous range of angles using grating sensors that are configured to exhibit Surface Plasmon Resonance effects at actinic wavelengths. The beam deviation measurement systems and procedures are applicable to both mask-based and maskless lithography tools. A control system adopts an appropriate calibration algorithm based on whether the SPR effect is detected or not. Relative intensity shift in an SPR-affected diffractive order, and/or relative position and slope change in non-SPR-affected diffractive orders are used as a basis of the adopted calibration algorithm.