Patent ID: 8382911

Claim:
A method for a stage device of an electron beam exposure system which conducts a cleaning operation and an electron beam exposure operation, the stage device 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; and a differential pumping portion to prevent the gas from flowing outside the gap portion between the movable stage and the fixed stage, the method comprising the steps of: controlling the cleaning operation by moving the movable stage within a predetermined range and regulating a pressure of a gas supplied to the air bearing via the pressure regulator; and setting a floating height of the movable stage in the cleaning operation lower than that in the electron beam exposure operation and setting a pressure in the differential pumping portion in the cleaning operation equal to that in the electron beam exposure operation, or setting the floating height of the movable stage in the cleaning operation equal to that in the electron beam exposure operation and setting the pressure in the differential pumping portion in the cleaning operation higher than that in the electron beam exposure operation.