KLA Corporation
Optical Etendue Matching Methods for Extreme Ultraviolet Metrology

Abstract:

An optical characterization system is disclosed. The optical characterization system may comprise a synchrotron source, an optical characterization sub-system, and a sensor configured to receive a projected image from a set of imaging optics. The optical characterization sub-system may include at least the set of illumination optics, a set of imaging optics, and a diffractive optical element, a temporal modulator or an optical waveguide configured to match an etendue of a light beam output by the synchrotron source to the set of illumination optics. A method of matching the etendue of a light beam is also disclosed.