A lithographic apparatus that includes an illumination system that conditions a radiation beam, a first stationary plate having a first surface, and a reticle stage defining, along with the first stationary plate, a first chamber. The reticle stage supports a reticle in the first chamber, and the reticle stage includes a first surface spaced apart from a second surface of the first stationary plate, thereby defining a first gap configured to suppress an amount of contamination passing from a second chamber to the first chamber. The first stationary plate is between the reticle stage and both the illumination system and a projection system configured to project a pattern imparted to the radiation beam by the patterning device onto a substrate.