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. 19, 2016
Filed:
Mar. 22, 2011
Jie LI, Milpitas, CA (US);
Zhuan Liu, Fremont, CA (US);
Silvio J. Rabello, Palo Alto, CA (US);
Nigel P. Smith, Hillsboro, CA (US);
Jie Li, Milpitas, CA (US);
Zhuan Liu, Fremont, CA (US);
Silvio J. Rabello, Palo Alto, CA (US);
Nigel P. Smith, Hillsboro, CA (US);
Nanometrics Incorporated, Milpitas, CA (US);
Abstract
An empirical diffraction based overlay (eDBO) measurement of an overlay error is produced using diffraction signals from a plurality of diffraction based alignment pads from an alignment target. The linearity of the overlay error is tested using the same diffraction signals or a different set of diffraction signals from diffraction based alignment pads. Wavelengths that do not have a linear response to overlay error may be excluded from the measurement error.