ASML Holding N.V.
Pneumatic support device and lithographic apparatus with pneumatic support device

Abstract:

The invention provides a pneumatic support device for a lithographic apparatus and a lithographic apparatus with such support device. The support device comprises a gas spring. The gas spring comprises a suspending part, a suspended part, and a pressure chamber configured for supporting the suspended part relative to the suspending part. The support device further comprises an actuator configured for positioning the suspended part relative to the suspending part, an acceleration sensor configured for generating a first sensor signal representative for the acceleration of the suspending part, a pressure sensor configured for generating a second sensor signal representative for the pressure in the pressure chamber, and a control unit. The control unit is configured to: receive the first sensor signal, receive the second sensor signal, filter the first sensor signal in a low-pass filter, filter the second sensor signal in a high-pass filter, determine, based on the filtered first sensor signal and filtered second sensor signal, a force exerted by the suspending part on the suspended part, and generate, based on said force, a control signal for the actuator.