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:
Apr. 19, 2016
Filed:
Nov. 13, 2013
Semiconductor Manufacturing International (Shanghai) Corporation, Shanghai, CN;
Boxiu Cai, Shanghai, CN;
Abstract
A method for monitoring the source symmetry of a photolithography system is provided. The method includes providing a first reticle; and providing a second reticle. The method also includes forming first bottom overlay alignment marks on a first wafer using the first reticle; and forming first top overlay alignment marks on the first bottom overlay alignment marks using the second reticle. Further, the method includes forming second bottom overlay alignment marks on a second wafer using the first reticle; and forming second top overlay alignment marks on the second bottom overlay alignment marks using the second reticle. Further, the method also include measuring a first overlay shift; measuring a second overlay shift; and obtaining an overlay shift caused by the source asymmetry based on the first overlay shift and the second overlay shift.