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:
Dec. 12, 2006
Filed:
Dec. 29, 2004
Anastasius Jacobus Anicetus Bruinsma, Delft, NL;
Frank Staals, Eindhoven, NL;
Robert Jan Van Wijk, Valkenswaard, NL;
Stoyan Nihtianov, Eindhoven, NL;
Anastasius Jacobus Anicetus Bruinsma, Delft, NL;
Frank Staals, Eindhoven, NL;
Robert Jan Van Wijk, Valkenswaard, NL;
Stoyan Nihtianov, Eindhoven, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
The invention relates to a level sensor for use in a lithographic apparatus that determines a surface height of a substrate. The level sensor includes an emitter and a receiver, wherein the emitter is arranged to emit a signal directed to a predetermined position on the surface of the substrate, such that the signal is at least partially reflected by the substrate to render a reflected signal. The receiver is arranged to receive at least part of the reflected signal, and the level sensor is arranged to determine the surface height of the substrate with respect to the level sensor based on the emitted and received signal. The signal includes a pressure wave.