APPARATUS AND METHOD FOR ALIGNING SUBSTRATE

PROBLEM TO BE SOLVED: To provide a simple apparatus for aligning a substrate at a low cost capable of rapidly conducting an alignment of the substrate in X-Y direction and θ direction by using a necessary minimum limit number of sensors. SOLUTION: The apparatus for aligning the substrate comprises a substrate stage WST for placing the substrate W, a rotating mechanism STa for rotating the stage WST at a predetermined axis AX as a center, a moving mechanism STb for moving the stage WST in a plane X-Y substantially perpendicular to the axis AX, first sensors 1a and 1b provided near a peripheral edge of the substrate W to sense a position of the substrate W in a rotating direction θ, and second sensors 2 provided near the peripheral edge of the substrate at a substantially symmetrical positions to the sensors 1a and 1b, thereby sensing the position of the first direction X substantially parallel to a surface of the substrate W by the sensors 1a and 1b and the sensors 2.