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:
Sep. 23, 1997
Filed:
Jan. 02, 1996
Masaya Iwasaki, Yokohama, JP;
Nikon Corporation, , JP;
Abstract
The thickness of a substrate is one of the most important parameters in detecting the flexure of the substrate. The thickness of a reference substrate disposed on a stage and its amount of flexure are measured. Thus measured data are stored in a memory of apparatus. Then, the apparatus measures the thickness of a substrate to be measured. The data concerning thus measured thickness of the substrate to be measured and the data concerning the thickness and amount of flexure of the reference substrate stored in the memory are utilized to calculate the amount of flexure of the substrate to be measured. This apparatus measures the pattern position of the substrate to be measured in thus flexed state. The apparatus corrects thus measured pattern position of the substrate to be measured on the basis of the amount of flexure which has been indirectly measured as mentioned above.