Patent ID: 8947641
Filing Date: 2015-02-03
Classification: G03F

Abstract:
1. A lithographic apparatus comprising: an illumination system configured to condition a radiation beam; a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam; a substrate table constructed to hold a substrate; a projection system configured to project the patterned radiation beam onto a target portion of the substrate; a support position sensor to measure a position of the support relative to a first structure of the lithographic apparatus; a patterning device position sensor located at a second structure of the lithographic apparatus to measure a position of the patterning device relative to the second structure, wherein the second structure is not connected to the first structure; and a control device configured to determine a correlation between a first component of the position of the patterning device and a second component of the position of the support from the position measured by the support position sensor, the position measured by the patterning device position sensor, and mutual positions of the first and second structures, wherein the first and second components are taken along a coordinate axis fixed relative to the first and second structures.