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AssigneesU.S. Philips Corporation, ASM Lithography B.V.
InventorsJacob J. 'T Mannetje, Frank Auer
Estimating the term…
Support device (53) provided with a first part (69) and a second part (71) which is supported relative to the first part by means of a gas spring (73) having a pressure chamber (75). A gas supply (117), which compensates for gas leakage from the pressure chamber (75) during operation, is connected to an intermediate space (119) which is in communication with the pressure chamber (75) via a pneumatic restriction (121). The gas pressure present in the intermediate space (119) is held as constant as possible during operation by means of a control loop (123), to prevent transmission of pressure fluctuations which are present in the gas supply (117) to the pressure chamber (75) as much as possible. Such pressure fluctuations are undesirable in the pressure chamber because they cause mechanical vibrations in the second part of the support device and the device to be supported. The support device is used in a lithographic device for the support of a frame (39) with respect to a base (37), the frame (39) supporting a focusing unit (5).
A support device comprising a first support part, a second support part, a gas spring with a pressure chamber for supporting the second support part relative to the first support part parallel to a support direction, an intermediate space which is connected to the pressure chamber via a pneumatic restriction, a gas supply connected to the intermediate space, and means for controlling a gas pressure prevailing in said intermediate space.
Dependencies are inferred from the claim text.