System and method for controlling a temperature of a reaction assembly

A stage assembly that moves a device along a first axis, the stage assembly comprising:

• a stage that retains the device;
• a stage base;
• a countermass reaction assembly that is supported by the stage base and that moves relative to the stage base along the first axis;
• a planar, stage mover that moves the stage, the stage mover including a magnet array that is coupled to the stage and a conductor array that is coupled to the reaction assembly, the conductor array including a set of first zone conductor units, and a set of second zone conductor units, wherein current directed to the conductor array generates a force that can move the magnet array and the stage along the first axis in a first direction, and the conductor array and the countermass reaction assembly along the first axis in a second direction that is opposite the first direction;
• wherein each conductor unit includes a first coil set, a second coil set, a body housing positioned near coil sets, and a surface housing;
• a temperature adjuster that directs (i) a body circulation fluid into the body housing of each of the first zone conductor units at a first flow rate and a first temperature, and into the body housing of each of the second zone conductor units at a second flow rate and a second temperature;
• and (ii) a surface circulation fluid through the surface housing of each of the conductor units to maintain the temperature of the surface housings at a predetermined surface temperature;
• a control system that controls the temperature adjuster to adjust at least one of the first flow rate and the first temperature to cool the first zone conductor units to a desired first temperature, and to adjust at least one of the second flow rate and the second temperature to cool the second zone conductor units to a desired second temperature, which may be the same as the desired first temperature.

A method for moving a device, the method comprising the steps of:

• retaining the device with a stage;
• positioning a reaction assembly near the stage;
• moving the stage with a stage mover that includes a magnet array that is coupled to the stage and a conductor array that is coupled to the reaction assembly, the conductor array including a set of first zone conductor units, and a set of second zone conductor units, wherein current directed to the conductor array generates a force that can move the magnet array and the stage relative to the reaction assembly;
• adjusting the temperature of the set of first zone conductor units, and the set of second zone conductor units with a temperature adjuster;
• and
• controlling the temperature adjuster with a control system.