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:
Jun. 13, 2000
Filed:
Jan. 22, 1999
Applicant:
Inventor:
Chi-Hung Wei, Hsinchu, TW;
Assignee:
United Integrated Circuits Corp., Hsinchu, TW;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438692 ; 438-8 ; 438747 ; 216 84 ; 216 88 ; 216 85 ;
Abstract
An alignment strategy for asymmetrical alignment marks in a wafer, in which the positions of the a symmetrical alignment marks are determined twice. A first set of positions is detected after a chemical-mechanical polishing step. A second set of positions is detected after a rotation in which the wafer is rotated by 180.degree. in the plane of the surface of the wafer.