Patent Number: 052767256
Section: abstract

An exposure apparatus usable with a mask having a pattern and a wafer having a radiation-sensitive surface layer, for transferring with a radiation energy beam the pattern of the mask to the wafer, is disclosed. The apparatus includes a mask supporting member for supporting the mask; a wafer supporting member for supporting the wafer; a reflective member having a reflection surface and an indication pattern, the reflective member being supported by one of the mask supporting member and the wafer supporting member; an arrangement for projecting a beam, which is thinner than the radiation energy beam and which advances along or about the axis of the radiation energy beam, upon the reflective member; a device for observing a positional relationship between the indication pattern and a spot formed by projection of the thinner beam upon the reflective member; and a device for correcting a relationship between the indication pattern and the spot, on the basis of the observation.