A 2-m grazing incidence monochromator with a silicon-carbide-based master grating for undulator radiation

Performance of a 2-m grazing incidence vacuum ultraviolet (VUV)/soft x-ray monochromator was evaluated with silicon-carbide-based master grating of 1200 lines/mm groove density that was newly developed for use of undulator radiation. Incident power density on the grating surface was as high as 120 mW/mm2. Surface observation of the grating after the test operation showed that the periodic structure and reflective surface of the grooves were well preserved, except for slight degradation of the groove edges, even though no active cooling system was equipped. Photon flux was of the order of 1012 photons/s. Efficiency of second-order diffraction relative to the first-order diffraction was 20%--50%. Resolving power of 2200 was achieved at 244.4 eV for 5-μm exit slit width