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:
Aug. 19, 2008
Filed:
May. 25, 2007
Joerg Bischoff, Illmenau, DE;
Shifang LI, Pleasanton, CA (US);
Xinhui Niu, Los Altos, CA (US);
Timbre Technologies, Inc., Santa Clara, CA (US);
Abstract
A structure formed on a semiconductor wafer is examined by obtaining measurements of cross polarization components of diffraction beams, which were obtained from scanning an incident beam over a range of azimuth angles to obtain an azimuthal scan. A zero azimuth position is determined based on the azimuthal scan. The cross polarization components are zero at the zero azimuth position. A measured diffraction signal is obtained using an azimuth angle to be used in optical metrology of the structure. Misalignment of the azimuth angle is detected using the measured diffraction signal and the determined zero azimuth position.