摘要 |
In a state that a wafer stage is not positioned in the center of the Y-direction traveling range, thrusts Fa, Fb supplied from a pair of linear motors to a Y-direction stage are made different and the Y-direction stage is moved in the X direction so that moments Ma, Mb about the centroid of the Y-direction stage by the thrusts Fa, Fb cancel each other. Since the moments Ma, Mb about the centroid generated by the thrusts cancel each other and the thrusts do not act as forces for rotating the Y-direction stage, the Y-direction stage is not deflected in a yawing direction. Such a stage device as constructed above can prevent deflection in a yawing direction due to displacement of the centroid position of an object to be positioned or a stage and precisely move the object to be positioned to a target position.
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