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. 17, 2000
Filed:
May. 13, 1999
Tsuyoshi Naraki, Setagaya-ku, JP;
Shuji Kawamura, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A projection exposure apparatus has a function to measure orthogonality between movement mirrors for interferometers for measuring positions of a substrate table in X and Y directions. The substrate table is moved by a distance L along a direction of a third axis which is included in an XY plane and inclined at an angle .alpha. with respect to a Y axis, while operating a movement mirror and an interferometer for the direction of the third axis. A component in the Y direction corresponding to the distance L in the direction of the third axis is defined as d. A movement distance of the substrate table in the X direction after movement of the substrate table by the distance L in the direction of the third axis is determined by the interferometer for measuring the position in the X direction, which is defined as S. An orthogonality error .theta. can be determined in accordance with .theta.=tan.sup.-1 [(d-S)/d]. The position of the substrate table can be correctly controlled by moving the substrate table while giving an offset to correct the error. This function can be also applied to a mask stage.