Fabrication and characterization of Sb/B4C multilayer mirrors for soft X-rays

Structure characterization of Sb/B4C multilayers for soft X-ray optics with a layers thickness from 0.5 nm to 7 nm is reported for the first time. Sb/B4C coatings were manufactured via magnetron sputtering. Amorphous and crystalline phases of the layers and the multilayer structure parameters were characterized with the X-ray diffraction data and the TEM data. The Sb/B4C multilayers demonstrated long term stability of their parameters and performances. The reached value of the reflectance of the Sb/B4C multilayers is 19-28% measured at the near-normal incidence in the wavelength range of 6.64-8.5 nm. The influence of reduced Sb density on the reflectivity is discussed.