摘要 |
A single field photomask includes a first set of targets formed on a first side of the photomask, and a second set of targets formed on a second side of the photomask, opposite the first side. In operation, the photomask is to be applied to a wafer without any alignment marks. The photomask forms a first set of alignment marks in the wafer from the first set of targets, and the photomask further forms a second set of alignment marks in the wafer from the second set of targets. The first set of alignment marks is used to align to a first field mask and the second set of alignment marks is used to align to a second field mask to stitch an image of the first field mask to an image of the second field mask.
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