Reticle discerning device, exposure equipment comprising the same and exposure method

Exposure equipment comprising:

• a plurality of reticles each having a central region, and a peripheral region extending around the central region, and defining in the central region a pattern to be illuminated so that the image of the pattern is transferred to a substrate;
• an exposure apparatus operative to illuminate the pattern of a selected one of the reticles and thereby transfer an image of the pattern to a substrate;
• a reticle transfer robot that transfers a selected one of the reticles to the exposure apparatus along a reticle transfer path;
• and
• a reticle discerning device, the reticle discerning device including a memory in which images of to-be-illuminated patterns of a plurality of reticles are stored as reference pattern images, respectively, a detection unit disposed alongside the reticle transfer path and comprising an optical image sensor that detects an image of the pattern of the reticle being transferred by the reticle transfer robot along the path, and a processing unit connected to said memory and to said detection unit and operative to compare the reference pattern images with images detected by the optical image sensor of said detection unit.

An exposure method comprising:

• transferring a reticle to an exposure apparatus;
• controlling the exposure apparatus to execute an exposure process in which the reticle transferred to the apparatus is illuminated and an image of a pattern of the reticle is thereby transferred to a substrate;
• and
• before the exposure apparatus is controlled to execute the exposure process, discerning the reticle from an image of the pattern of the reticle to be illuminated in the exposure apparatus.