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. 16, 2012
Filed:
Nov. 19, 2008
Gerardus Carolus Johannus Hofmans, Eindhoven, NL;
Hubertus Antonius Geraets, Arendonk, BE;
Mark Zellenrath, Veldhoven, NL;
Sven Gunnar Krister Magnusson, Veldhoven, NL;
Gerardus Carolus Johannus Hofmans, Eindhoven, NL;
Hubertus Antonius Geraets, Arendonk, BE;
Mark Zellenrath, Veldhoven, NL;
Sven Gunnar Krister Magnusson, Veldhoven, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
A method of measuring focus of a lithographic projection apparatus includes exposure of a photoresist covered test substrate with a plurality of verification fields. Each of the verification fields includes a plurality of verification markers, and the verification fields are exposed using a predetermined focus offset FO. After developing, an alignment offset for each of the verification markers is measured and translated into defocus data using a transposed focal curve. The method according to an embodiment of the invention may result in a focus-versus alignment shift sensitivity up to 50 times higher (typically dX,Y/dZ=20) than conventional approaches.