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:
Oct. 08, 2002
Filed:
Jul. 20, 1999
Hiroaki Takeishi, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A scanning exposure apparatus has a wafer stage, a reticle stage, a projection optical system for projecting an image of a reticle onto a substrate on the wafer stage, X-Y laser interferometers for measuring the position of the wafer stage in the X direction, Z interferometers for measuring the wafer stage position in the Z direction, and X-Y laser interferometers for measuring the position of the reticle stage in the X and Y directions, and transfers the image of the reticle onto the wafer by exposure while synchronously driving the wafer stage and reticle stage. The exposure apparatus includes a plurality of laser heads for generating laser beams to be provided to the interferometers. A reference signal is supplied from one laser head to the remaining laser heads to synchronize all laser heads.