Method and system for overlay control using dual metrology sampling

摘要

A system and method are provided for determining an overlay of a first layer N-1 and a second layer N that are positioned one over the other on a substrate. The first layer includes a first overlay portion. The second layer includes a first complementary overlay portion. The first overlay portion and first complementary overlay portion are arranged to form an overlay mark for determining the overlay of the first and second layers. In the second layer a stitching portion and a complementary stitching portion are formed. The stitching portion and complementary stitching portion are arranged to form a stitching mark for determining a stitching overlay between the second layer and an adjacent second layer, with the adjacent second layer being positioned adjacent to the second layer.