LITHOGRAPHY MEASUREMENT USING SCATTEROMETRY

摘要

A lithographic apparatus includes an illuminator configured to condition a beam of radiation and a support configured to hold a patterning device. The patterning device is configured to pattern the beam of radiation according to a desired pattern. The lithographic apparatus also includes a substrate table configured to hold a substrate and a projection system configured to project the patterned beam onto a target portion of the substrate to form a patterned image on the substrate. The apparatus further includes a sensor configured and arranged to intercept a portion of the beam and to measure a transmission of the beam through at least a portion of the patterning device.