Patent ID: 7768625

Claim:
An exposure apparatus which exposes a pattern on a mask onto an object by relatively scanning the object and the mask in a scanning direction, said exposure apparatus comprising: (a) a projection optical system configured to project a reticle pattern onto a plate by using light from a light source; and (b) a photo detector unit configured to detect the light projected by said projection optical system, wherein said photo detector unit includes: (i) a fluorescent substance that emits a fluorescence in accordance with an intensity of light; (ii) a substrate, which is patterned with a wiring pattern, and is configured to transmit the light and to introduce the light to said fluorescent substance; (iii) a plurality of detectors configured to detect the fluorescence, said plurality of detectors being arranged in the scanning direction; (iv) an absorber film that absorbs light reflected by each of said plurality of the detectors; and (v) plurality of bumps configured to space said fluorescent substance from said plurality of detectors, and to electrically connect said plurality of detectors and the wiring pattern of said substrate, wherein a width of said fluorescent substance is smaller than a width of said plurality of detectors, in a direction perpendicular to the scanning direction.