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:
Aug. 10, 1999
Filed:
Feb. 04, 1998
Applicant:
Inventors:
Masanobu Ito, Kawasaki, JP;
Masamitsu Yanagihara, Zama, JP;
Hideji Goto, Chiba, JP;
Yoshiyuki Katamata, Tokyo, JP;
Assignee:
Nikon Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ; G03B / ; G03B / ; G01B / ;
U.S. Cl.
CPC ...
355 55 ; 355 53 ; 355 77 ; 356401 ;
Abstract
To improve the focus accuracy during alignment and to improve the alignment accuracy even if a substrate has warpage, during alignment, an approximate focus plane is obtained by using only the detection results at focus points of focus sensors located near the ends of a substrate, close to alignment points, and without using the detection results at focus points of two central focus sensors. The auto-focus operation is performed by using the above operation results. As a result, a substrate is driven so as to be adjusted to the approximate focus plane during alignment.