Patent ID: 8281794

Claim:
A stage device for use in an electron beam exposure system, comprising: a gas supply unit to generate gas; a pressure regulator to regulate a pressure of the gas; a frame-shaped movable stage having a sample mounting surface; a fixed stage having a surface facing an opposite surface of the movable stage from the sample mounting surface, the fixed stage being surrounded by the movable stage; an air bearing to float the movable stage by supplying the gas to a gap portion between the fixed stage and the movable stage; a differential pumping portion to prevent the gas from flowing outside the gap portion between the movable stage and the fixed stage; and a controller to control the gas supply unit, the pressure regulator, the movable stage, and the differential pumping portion, in a cleaning operation and in an electron beam exposure operation; wherein the controller controls the cleaning operation by moving the movable stage within a predetermined range and regulating the pressure of the gas supplied to the air bearing via the pressure regulator; and wherein the floating height of the movable stage in the cleaning operation is set lower than that in the electron beam exposure operation and the pressure in the differential pumping portion in the cleaning operation is set equal to that in the electron beam exposure operation, or the floating height of the movable stage in the cleaning operation is set equal to that in electron beam exposure operation and the pressure in the differential pumping portion in the cleaning operation is set higher than that in the electron beam exposure operation.