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. 18, 2011
Filed:
Jan. 21, 2009
Shankar Krishnan, Santa Clara, CA (US);
Haixing Zhou, Sunnyvale, CA (US);
Haiming Wang, Fremont, CA (US);
David Lidsky, San Jose, CA (US);
Walter Dean Mieher, Los Gatos, CA (US);
Shankar Krishnan, Santa Clara, CA (US);
Haixing Zhou, Sunnyvale, CA (US);
Haiming Wang, Fremont, CA (US);
David Lidsky, San Jose, CA (US);
Walter Dean Mieher, Los Gatos, CA (US);
KLA-Tencor Corporation, San Jose, CA (US);
Abstract
Methods and apparatus for measuring an optical azimuth angle φof a substrate relative to a plane of detection in scatterometry tools are disclosed. A grating target on a stage of a scatterometry tool may be illuminated and positions of the resulting diffraction orders may be observed. The optical azimuth angle may be determined from the positions of the diffraction orders. Alternatively, polarization-dependent signals of radiation scattered from a line grating may be measured for equal and opposite polarization angles +A and −A. A combination signal may be computed from the polarization-dependent signals obtained at +A and −A and a property of the combination signal may be calculated for several mechanical Azimuth angles φ. A relationship between the optical azimuth angle φand the mechanical azimuth angle φmay be determined from a behavior of the property as a function of mechanical azimuth angle φ.