Patent ID: 7034924

Claim:
A lithographic apparatus comprising: an illumination system constructed to provide a beam of radiation; at least one first object support structure constructed to support a patterning device, said patterning device serving to impart a cross-section of said beam with a pattern to form a patterned beam; at least one second object support structure constructed to support a substrate; a projection system that projects said patterned beam onto a target portion of said substrate; and at least one main vacuum chamber provided with a first gas evacuating structure to provide a high vacuum, said main vacuum chamber enclosing at least one of said first and second support structures and enclosing positioning structures having at least one positioning device and associated with at least one of said first and second support structures, wherein said at least one of said first and second support structures in said main vacuum chamber includes a carrier device connected to said at least one positioning device and being within said main vacuum chamber, wherein said carrier device includes at least one compartment shielded from said high vacuum of said main vacuum chamber and being provided with a further gas evacuating structure allowing, in operation in said at least one compartment, at least one vacuum level which is different from said high vacuum in said main vacuum chamber.