Design of a flat-field soft X-ray spectrometer with a wideband Ni/C multilayer grating covering the range of 1 to 3.5 keV

Imazono, Takashi; Koike, Masato; Kuramoto, Satoshi*; Nagano, Tetsuya*; Koeda, Masaru*

We designed a flat-field soft X-ray spectrometer to detect X-rays from 1 to 3.5 keV emitted from the CIS absorber consisting of Cu, In, and Se in a CIS solar cell. We invented a wideband multilayered grating, which was coated with an aperiodic Ni/C multilayer on a laminar-type varied-line-spacing grating, to cover the whole energy range at a constant angle of incidence. Since there is no mechanical movement of the grating and a detector, the spectrometer can provide quick and accurate measurements in the 1-3.5 keV range as well as high resolution analysis.