Patent ID: 7106896

Claim:
A semiconductor wafer ID recognition apparatus comprising: image sensing optical means for reading a plurality of identification information character strings (IDs) marked at an arbitrary position on a semiconductor wafer in accordance with a plurality of first read optical conditions registered in advance; and recognition processing means for performing recognition processing including calculation of an evaluation score representing a read likelihood ratio for an image output from said image sensing optical means for every read optical condition, and for adopting a recognition result for the character string exhibiting the highest score as an ID of the semiconductor wafer under the read optical condition, the highest score being adopted only if it is no less than a predetermined minimum score, wherein said recognition processing means performs recognition processing for a corresponding ID among a plurality of IDs recorded on the semiconductor wafer in accordance with the first read optical conditions, and adopts, as the ID of the semiconductor wafer, a recognition result under a read optical condition exhibiting the highest score obtained by recognition processing under all the first read optical conditions.