Patent ID: 6421112
Filing Date: 2002-07-16
Classification: F16C,G03F

Abstract:
A lithographic projection apparatus, comprising:a radiation system constructed to supply a projection beam of radiation; a first object table provided with a mask holder for holding a mask; a second object table provided with a substrate holder for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; a vacuum chamber having a wall enclosing at least one of said first and second object tables, said vacuum chamber wall having at least one wall aperture therein; an elongate beam extending through said wall aperture, a part of said beam extending into said vacuum chamber to support said one object table therein and a part of said beam extending outside said vacuum chamber, whereby displacement of said beam outside said vacuum chamber causes displacement of said object table inside said vacuum chamber; a seal constructed and arranged to seal said wall aperture while allowing displacement of said beam; and a beam positioning assembly constructed and arranged to displace said beam, thereby to displace said object table within said vacuum chamber.