摘要 |
Since a mask stage 16 and a substrate stage 14 are supported in a floating manner over a base member 12, the both stages are driven in mutually opposite directions in a non-contact manner along the scanning direction by the aid of a linear motor 13. During this process, the movement of the both stages 16, 14 does not exert any force on the base member 12 and other components, and thus the momentum is conserved. The mass ratio between the stage 16 and the stage 14 is set to be identical with a reduction magnification of an unillustrated projection optical system. Therefore, according to the law of conservation of momentum, the velocity ratio between the stage 16 and the stage 14 is a reciprocal number of the reduction magnification of the projection optical system. Thus, the both stages 16, 14 are subjected to accurate synchronous control. It is possible to suppress inclination and fluctuation of the entire apparatus, and it is possible to improve the synchronization performance of the mask stage and the substrate stage.
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