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. 11, 2011
Filed:
Dec. 25, 2006
Fan Wang, Shanghai, CN;
Mingying MA, Shanghai, CN;
Xiangzhao Wang, Shanghai, CN;
Shanghai Micro Electronics Equipment Co., Ltd., Shanghai, CN;
Abstract
A method for in-situ aberration measurement in an optical imaging system of lithographic tools. According to the method, a reticle pattern is imaged to form an imaged pattern by transmitting beams through a reticle via the optical imaging system. The imaged reticle pattern is shaped to have plural groups of imaged linewidths. The plural groups of imaged linewidths are measured using either of an image sensor, a CD-SEM and a microscope by modifying the intensity distribution at an exit pupil plane of the optical imaging system. The asymmetry and ununiformity of the imaged linewidths are calculated. Aberrations of the optical imaging system are calculated.