Now, FIG. 14A is a top plan view of an eighth embodiment of a stage according to the invention, and FIG. 14B is a section view taken along the line A-A??? shown in FIG. 14A. In the eighth embodiment as well, similarly to the sixth and seventh embodiments, a stage base plate 3 disposed in the interior portion of a vacuum chamber 1 is supported in a cantilevered manner by a Y slide shaft 2 which is