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. 12, 2010
Filed:
Jun. 15, 2007
Paulus Antonius Andreas Teunissen, Eindhoven, NL;
Petrus Johannes Maria Broodbakker, Eindhoven, NL;
Rene Marinus Gerardus Johan Queens, Eindhoven, NL;
Paulus Antonius Andreas Teunissen, Eindhoven, NL;
Petrus Johannes Maria Broodbakker, Eindhoven, NL;
Rene Marinus Gerardus Johan Queens, Eindhoven, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
A level sensor for a lithographic projection apparatus according to one embodiment of the invention includes a light source, a first reflector, a second reflector and a detector. The first reflector is positioned to direct light from the light source towards a wafer surface, and the second reflector is positioned to direct light reflected from the wafer surface to the detector. The first and second reflectors are selected to incur a minimal process dependent apparent surface depression.