Extended knife-edge method for characterizing sub-10-nm X-ray beams

We describe a method for characterizing sub-10-nm X-ray beams using knife-edge scanning with dark-field geometry. Beam profile measurement by the conventional dark-field method is simulated numerically, and the signal intensity is found to depend strongly on the incident angle of the beam components. A numerical procedure to correct the dependence and to determine the actual beam profile is presented.