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. 27, 2000
Filed:
Jan. 29, 1999
Takashi Miyachi, Kounosu, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Disclosed is a projection exposure apparatus which is able to realize stabilized focusing control which presents highly followable performances for the photosensitive substrate with few irregularities and will work without failure even for a photosensitive substrate having rough irregularities. A determining section determines whether the velocity instructions data obtained by a difference between a detected position of the substrate and a target position and a difference between the detected tilt of the substarate and a target tilt falls within respective predetermined allowable ranges. During the affirmative judgment by the determining section, a controller performs focusing and leveling control with high precision. When the determining section makes a negative judgment, the controller effects focusing control with the tilt of the wafer kept at constant.