| 摘要 |
PROBLEM TO BE SOLVED: To enable highly accurate positioning by providing it with a noncontact bearing which supports a main stage and a sub stage in noncontact in the direction where the sub stage shifts, and a noncontact actuator which generates power between the main stage and the sub stage. SOLUTION: An XY stage 1 shifts a top plate 51 in XY direction to a surface plate 50. Three pieces of linear motors bring a retention board 4 and the top plate 51 close to or away from each other in z direction. The apparent bearing rigidity of a radial static pressure bearing 7 can be adjusted by an xy linear motor (noncontact actuator) which is provided in parallel with a radial static pressure bearing (noncontact bearing) 7 which supports the retention plate 4 in noncontact in XY direction to the top plate 51, so that the shifting in XY direction (shifting direction) of the retention plate (main stage) 4 may not cause phase lag to the shifting in XY direction by the XY stage (shifting mechanism) 1 of the top plate (sub stage) 51. |
