Active disturbance compensation of acceleration-driven pressure pulses in a water-conditioned positioning device

摘要

The present development relates to compensation of acceleration driven pressure pulses in a water-conditioned positioning device adversely affecting the position accuracy of the positioning device. Positioning devices, especially high-accuracy positioning devices, e.g. as used in a lithographic apparatus for positioning wafers or masks, may include a cooling system allowing thermal stability of sensors, actuators, clamps, etc. to reduce heating effects in the objects to be positioned. Alternatively or additionally, the cooling system may reduce deformations of components of the positioning device and/or reduce motor constanl variations.