| US 7,499,180 B2 | ||
| Alignment stage, exposure apparatus, and semiconductor device manufacturing method | ||
| Tadashi Hattori, Tochigi (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Dec. 30, 2002, as Appl. No. 10/330,081. | ||
| Claims priority of application No. 2002-000686 (JP), filed on Jan. 07, 2002. | ||
| Prior Publication US 2003/0133125 A1, Jul. 17, 2003 | ||
| Int. Cl. G01B 9/02 (2006.01) | ||
| U.S. Cl. 356—510 | 11 Claims |

| 1. An alignment stage apparatus having a stage movable along a surface of a surface plate, said stage apparatus comprising:
a plane mirror which extends in two directions substantially perpendicular to each other in order to measure a position of
the stage in a translation direction and a tilt of the stage in the direction of height;
first measurement means for irradiating a laser beam to said plane mirror and measuring the position of the stage in the translation
direction by using reflection of the laser beam;
second measurement means for irradiating a laser beam to said plane mirror and measuring the position of the stage by using
reflection of the laser beam at a position spaced apart from said first measurement means, in the direction of height, in
order to measure a tilt of the stage;
a plurality of third measurement means for measuring a tilt of the stage in the direction of height by measuring a plurality
of positions in the direction of height of the stage, wherein a measurement distance in which said plurality of third measurement
means are arranged is larger than a distance between said first measurement means and said second measurement means;
arithmetic means for calculating, when said first measurement means, said second measurement means and said plurality of third
measurement means perform the measurement while the stage moves in the translation direction, an error of a surface of said
plane mirror corresponding to the position of the stage, on the basis of a difference between a first tilt amount and a second
tilt amount, wherein the first tilt amount is obtained by calculating a difference between a measurement result measured by
said first measurement means and a measurement result measured by said second measurement means, and the second tilt amount
is obtained based on measurement results measured by said plurality of third measurement means; and
control means for correcting the first tilt amount based on the error calculated by said arithmetic means and controlling
a driving of the stage based on the correction result.
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