LITHOGRAPHY APPARATUS AND METHOD OF DETERMINING POLARIZATION PROPERTY

PROBLEM TO BE SOLVED: To provide a method for obtaining polarization property of a lithography apparatus. SOLUTION: The lithography apparatus includes an illumination system IL, a support, a substrate table, a projection system PS, and a detector 14. The apparatus further includes: a polarization changing element 10, such as a quarter-wave plate, that is adjustable; and a polarization analyzer 12, such as a linear polarizer, wherein the polarization changing element and the polarization analyzer are arranged in the radiation beam path at a position at which a patterning device is held by the support. By taking intensity measurements, using the detector 14, for different rotational orientations of the polarization changing element 10, information on the state of polarization of the radiation at the position of the patterning device can be obtained. Because the polarization analyzer 12 is located before the projection system PS, the measurements are not affected by the fact that the detector 14 is located after the projection system PS, such as at the level of the substrate. COPYRIGHT: (C)2010,JPO&INPIT