摘要 |
A simple, powerful technique for facilitating defect inspection in manufactured articles, especially articles used in or resulting from semiconductor fabrication. In the case of an article having a chrome and glass pattern thereon, such as a reticle or other article used in photolithography, a master version is identified, in as pristine a fashion as possible. That master version is imaged and stored, and that image used subsequently for comparison to other correspondingly patterned articles as part of an inspection process. The data provided by reading the recorded image of the master article substitutes for data derived from prior Die to Die or Die to Database comparisons. The invention also is directed to an apparatus which enables the nonvolatile storage of one or more of such master versions for use in article inspection.
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