Patent ID: 8130366
Filing Date: 2012-03-06
Classification: G03F

Abstract:
1. Method for alignment of a substrate, the substrate comprising a mark in a scribe lane, the scribe lane extending along a longitudinal direction as a first direction, the mark having a periodic structure in the first direction and a mark structure extending in a second direction perpendicular to the first direction, the periodic structure having a repeating distance in the first direction, the method comprising: providing an illumination beam for scanning the mark in the second direction; scanning a spot of the illumination beam in the second direction along a first scan path across the mark; scanning the spot of the illumination beam in the second direction along a second scan path across the mark, the second scan path being parallel to the first scan path, wherein the second scan path is shifted along the first direction relative to the first scan path over a first shift, the first shift corresponding to a fraction of the repeating distance of the periodic structure in the first direction.