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:
Jul. 21, 2009
Filed:
Aug. 15, 2006
Arie Jeffrey Den Boef, Waalre, NL;
Mircea Dusa, Campbell, CA (US);
Everhardus Cornelis Mos, Best, NL;
Maurits Van Der Schaar, Eindhoven, NL;
Stefan Carolus Jacobus Antonius Keij, Breda, NL;
Arie Jeffrey Den Boef, Waalre, NL;
Mircea Dusa, Campbell, CA (US);
Everhardus Cornelis Mos, Best, NL;
Maurits Van Der Schaar, Eindhoven, NL;
Stefan Carolus Jacobus Antonius Keij, Breda, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
An inspection system is arranged to measure an overlay error by projecting a plurality of radiation beams, differing in wavelength and/or polarization, onto two targets. A first radiation beam is projected onto a first target and the reflected radiation Ais detected. The first target comprises two gratings having a bias +d with respect to each other. The first radiation beam is also projected on to a second target, which comprises two gratings having a bias −d with respect to each other, and the reflected radiation Ais detected. A second radiation beam, having a different wavelength and/or polarization from the first radiation beam, is projected onto the first target and reflected radiation Ais detected and projected onto the second target and reflected radiation Ais detected. Detected radiations A, A, A, and Ais used to determine the overlay error.