| US 7,518,717 B2 | ||
| Exposure apparatus and a device manufacturing method using the same | ||
| Hiroaki Takeishi, Utsunomiya (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Aug. 28, 2006, as Appl. No. 11/467,710. | ||
| Application 11/114158 is a division of application No. 10/207768, filed on Jul. 31, 2002, granted, now 6,897,949, filed on May 24, 2005. | ||
| Application 11/467710 is a continuation of application No. 11/114158, filed on Apr. 26, 2005, granted, now 7,339,662. | ||
| Application 10/207768 is a continuation of application No. 09/418253, filed on Oct. 15, 1999, granted, now 6,456,374, filed on Sep. 24, 2002. | ||
| Claims priority of application No. 1998-313957 (JP), filed on Oct. 19, 1998. | ||
| Prior Publication US 2007/0030465 A1, Feb. 08, 2007 | ||
| Int. Cl. G01N 21/00 (2006.01); G01B 11/00 (2006.01) | ||
| U.S. Cl. 356—237.2 [356/237.3; 356/614; 356/394] | 12 Claims |
| 1. An exposure apparatus for performing an exposure of a Wafer to light via a mask while the mask and the wafer are scanned,
said apparatus comprising:
a projection optical system configured to project a pattern of the mask onto the wafer;
a detection system configured to detect a position of a surface of the wafer in a direction of an optical axis of said projection
optical system, with respect to each of a plurality of positions on the surface arranged along a direction of a scan of the
wafer, while the scan is performed;
a wafer stage configured to hold the wafer and to be moved, based on positions of the surface detected by said detection system,
while the exposure is performed; and
a controller configured to calculate a difference and to compare the difference with a threshold, the difference being a difference
between two detected positions of a plurality of detected positions of the surface, the plurality of the detected positions
of the surface being obtained by said detection system while the scan is performed, the two detected positions being obtained
with respect to two successive positions of the plurality of positions on the surface, and each of the plurality of detected
positions of the surface being obtained with respect to each of the optical axis direction and tilt directions, the difference
being calculated and compared with the threshold with respect to each of the optical axis direction and the tilt directions
to determine particle existence or particle non-existence on the wafer.
|