The method of manufacturing and the results of studies of a lens corrector that converts a spherical diverging front into a plane one and is intended for studying flat surfaces as part of an interferometer with a diffraction comparison wave is described. A feature of the corrector is the use of an aspherical convex surface with a maximum deviation of ∼200 μm from the nearest sphere. The first experimental results are presented, indicating the prospects for using ion-beam processing to improve the quality of the wavefront. After the procedure of ion-beam processing, the aberrations over the entire aperture of the corrector decreased by more than 4 times and amounted to the parameter of the height difference PV = 207 nm (∼λ/3) and RMS = 19.2 nm (∼λ /33). On an area with a diameter of 80%, the aberrations fell to the nanometer level: PV = 65 nm (∼λ/10) and RMS = 8.3 nm (∼λ/76).

The paper proposes the use of diamond-carbide-silicon composite "Skeleton"® coated with amorphous silicon as substrates for multilayer X-ray mirrors for powerful synchrotron radiation sources (3rd+ and 4th generation). The surfaces with the following parameters were obtained using standard deep polishing methods: flatness at the level of RMS90%=54.2 nm; effective roughness sigmaeff~1.0 nm; high-frequency roughness sigma2х2~0.1 nm.

By the method of ion-beam shape correction, a small-sized ion beam formed a non–axisymmetric aspherical profile of the collector surface for an extreme ultraviolet radiation source TEUS-S100 with a numerical aperture of NA= 0.25, PV on the surface is 36.3 microns, the surface shape accuracy by standard deviation is 0.074 microns, which allowed to obtain a focusing spot with a width of 300 microns at half-height. To solve the problem, the technological ion source KLAN-53M was upgraded – the flat ion-optical system was replaced with a focusing one. The ion-optical system consisting of a pair of concave grids with a radius of curvature of 60 mm provided the following parameters of the ion beam: the ion current is 20 mA, the width at half–height is 8.2 mm at a distance of 66 mm from the cutoff of the ion source.

Silicon nitride membranes were experimentally obtained as substrates for biological samples, which are examined using a microscope with an operating wavelength of 13.8 nm. The free-hanging films obtained have a size of up to 1.5 x 1.5 mm2, which makes it possible to select an area of interest for investigation on the sample on the order of tens to hundreds of microns. The mechanical strength of the membranes satisfies that the samples do not tear the membranes and withstand transportation. The results obtained are an import-substituting technology for the manufacture of Si3N4 membranes. The resulting membranes have a transparency of more than 40% in the range of the “water transparency window” (2.3–4.4 nm) and EUV (13–15 nm). The developed technology will become the basis for creating cuvettes for living biological samples for soft X-ray microscopy studies.