Patent ID: 7683351

Claim:
A lithographic apparatus, comprising: a support structure configured to support a patterning device, the patterning device being capable of imparting a radiation beam with a mask pattern in a cross-section of the radiation beam to form a patterned radiation beam; a substrate table configured to hold a substrate; a projection system configured to project the patterned radiation beam as a pattern image onto a target portion of the substrate along a scan path, the scan path being defined by a trajectory in a scanning direction of an exposure field of the lithographic apparatus; and a control system configured to correct local overlay errors within the pattern image in the target portion of the substrate along the scan path by dynamic intra-field correction during the scan of the pattern image in said target portion, wherein the dynamic intra-field correction provides varying adjustments from one point along the scan path relative to another point along the scan path based on a relative distortion between the two points.