ASML Holding N.V.
Optical detector

Abstract:

A detector for detecting diffracted radiation which has been diffracted by a regular structure; said detector comprises: a sensor for sensing at least a portion of said diffracted radiation, said sensor having a first region and a second region; a first coating configured to allow transmission of radiation with wavelengths within a first range of wavelengths; and a second coating configured to allow transmission of radiation with wavelengths within a second range of wavelengths; wherein said first coating coats said first region of said sensor, and said second coating coats said second region of said sensor, and wherein said first and second regions are different regions.