Patent ID: 7109508

Claim:
An exposure apparatus which exposes an object with an exposure beam irradiated on a mask, comprising: a mark detecting system of which an illumination system to illuminate a mark on the substrate and a detecting system to detect the illuminated mark are arranged at a same side with respect to the substrate, the illumination system including a first optical system disposed on an optical path through which an illumination beam from a beam source passes to irradiate onto the mark the illumination beam along a plane substantially perpendicular to a periodic direction of the mark, and the detecting system including a second optical system optically aligned with the first optical system, on which plural pairs of two diffracted beams of same order generated from the mark with the illumination beam are incident through a part of the first optical system and of which a deflection element is disposed in a space where the plural pairs of two diffracted beams are separated from each other to direct the plural pairs of two diffracted beams to different reference gratings respectively, and receiving beams from the different reference gratings on which the plural pairs of two diffracted beams are irradiated, the plural pairs of two diffracted beams including at least a first pair of ±nth-order (n is a natural number) diffracted beams and a second pair of ±mth-order (m is a natural number other than n) diffracted beams; and a stage on which the substrate is provided, that moves in a predetermined plane substantially perpendicular to an optical axis of the mark detecting system.