05623853 is referenced by 414 patents and cites 63 patents.

An XY stage for precision movement for use in aligning a wafer in a microlithography system. A main stage supporting the wafer straddles a movable beam that is magnetically driven in a first linear direction in the XY plane. A follower stage, mechanically independent of the main stage, also moves in the first linear (X) direction and its motion is electronically synchronized by a control system with the main stage motion in the X direction. Electromagnetic drive motors include magnetic tracks mounted on the follower stage which cooperate with motor coils mounted on the edges of the main stage to move the main stage in a second linear (Y) direction normal to the X direction. Thus the main stage is isolated from mechanical disturbances in the XY plane since there is no mechanical connections and is lightened by removing the weight of the magnetic tracks from the beam. A cable follower stage moves in the Y direction on the follower stage and supports the cables connecting to the main stage, thereby reducing cable drag. An air circulation system is provided in the magnetic tracks on the follower stage to remove heat from operation of the electromagnetic motors. Air is removed from a central region of each track by a vacuum duct enhanced by air plugs fitting at the two ends of the motor coil assembly on the main stage to contain the air therein.

Title
Precision motion stage with single guide beam and follower stage
Application Number
8/325740
Publication Number
5623853
Application Date
October 19, 1994
Publication Date
April 29, 1997
Inventor
Akimitsu Ebihara
San Mateo
CA, US
Uday G Nayak
San Jose
CA, US
Zahirudeen Premji
Boulder
CO, US
W Thomas Novak
Hillsborough
CA, US
Agent
Skjerven Morrill MacPherson Franklin & Friel
Agent
Norman R Klivans
Assignee
Nikon Precision
CA, US
IPC
G05G 11/00
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