US Patent 7193339 Positioning apparatus and charged-particle-beam exposure apparatus

A positioning apparatus includes a movable member for transmitting a driving force in a driving-axis direction to a stage, a first electromagnet for driving the movable member in the driving-axis direction by forming a magnetic path between the movable member and the first electromagnet and generating first magnetic flux, and a second electromagnet, which is positioned away from the first electromagnet and arranged in an overlapping direction, for driving the movable member in the same direction as the driving-axis direction of the first electromagnet by forming a magnetic path between the movable member and the second electromagnet and generating second magnetic flux having an inverted plurality from the first magnetic flux.