Abstract: A lithographic device comprising a mask table (5), a projection system (3), a substrate table (1) which is displaceable relative to the projection system (3) by means of a drive unit (21), and a measuring system (39) for measuring a position of the substrate table (1) relative to the projection system (3). A stationary part (157) of the drive unit (21) is fastened to a machine frame (85) of the lithographic device, while a stationary part (51, 53, 55) of the measuring system (39) is fastened to a reference frame (89) of the lithographic device which is dynamically isolated from the machine frame (85) by means of dynamic isolators (95). This prevents vibrations caused in the machine frame (85) by reaction forces of the drive unit (21) from being transmitted to the reference frame (89), so that the accuracy of the measuring system (39) is not adversely affected by such vibrations.
Type:
Grant
Filed:
January 30, 1997
Date of Patent:
September 14, 1999
Assignee:
U.S. Philips Corporation
Inventors:
Gerard Van Engelen, Frank B. Sperling, Henricus W. A. Janssen, Adianus G. Bouwer, Cornelis D. Van Dijk, Johannes M. M. Van Kimmenade, Jan Van Eijk, Adrianus Van Der Pal