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. 22, 2002
Filed:
Jan. 11, 2000
Ming-Fa Chen, Hsin-Chu, TW;
Chih-Chien Hung, Hsin-Chu, TW;
Chia-Hsiang Chen, Hsin-Chu, TW;
Fu-Tien Wong, Taow-Yuan, TW;
Taiwan Semiconductor Manufacturing Company, Ltd, Hsin Chu, TW;
Abstract
A method of forming circuit patterns on a semiconductor wafer using two different image steppers having nonaligned optical image systems achieves optical alignment of multiple overlays with high accuracy. A first alignment mark is imaged by the first stepper onto a material layer deposited on the wafer, and a second alignment mark is imaged onto a subsequently deposited material layer using the second stepper. Alignment of the two marks, and thus of successively imaged, overlying circuit patterns, is achieved by translating the optical coordinates of the second alignment system into the those of the first alignment system, and then making corresponding two dimensional adjustment of the wafer position relative to the second stepper.