摘要 |
A lithographic apparatus includes an illumination system to supply a beam of radiation, a patterning system serving to impart the beam of radiation with a pattern in its cross-section, a substrate table to support a substrate, and a projection system to project the patterned beam onto a target portion of the substrate. The substrate table includes a support member having an upper support surface for supporting at least part of the target portion of the substrate on a fluid cushion. The apparatus further includes a fluid supply system arranged to supply fluid to the upper support surface so as to provide the cushion, and an actuator system arranged to act on the support member. The actuator system is controllable to provide adjustment of a topography of the upper support surface relative to a reference plane. Compensation can thus be made for substrate thickness irregularities, to achieve correct focusing of the beam onto the target surface.
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