ИСТИНА

The compact high-resolution small-angle synchrotron radiation technique with tunable probe size was suggested. Preliminary test experiments were carried out at the microoptics test bench of the ID06 beamline, ESRF. The microradian X-ray diffraction with the beam energy of about 12 keV (λ = 1 Å , Δλ/λ ∼ 10−4) was realized using the set of compound refractive lenses (CRL), which consists of 30 parabolic lenses with 200 μm curvature radius, giving a focal length of 1.45 m and providing coherent illumination on the sample. The beam was focused at the twodimensional high resolution Sensicam CCD detector (0.645×0.645 μm2 pixel size). Using of thedistance between the compound lenses and the detector as a sample position is a novel approach. The probe size could be vary from 4 to 500 μm depending on the sample position. In the capacity of the test sample we have used an anodic alumina membrane with the thickness of 96 μm and self-ordered pore structure (pore diameter – 40 nm, distance between the centers of the pore – 102 nm). The membrane was installed perpendicularly to the incident beam on the distance from 246 to 16 mm from the detector. In this way the adjustment of an exposing area size from 87 to 4.2 μm and focusing on the area of one or few pore structure domains became possible. If the irradiated sample area consists of a few domains, the diffraction peaks on the 2D-diffraction pattern split into the speckles. The source of the important information about the real ordering and orientation of the pores into the each domain is the azimuthal and radial location of the speckle and their intensity. The analysis of speckles allowed to reveal that the pores into each domain have high degree of ordering in transversal direction, and they are longitudinal for all thickness of the membrane. At the same time using method of analysis of the all diffraction peak area usually gives the average information and distorts the data about the features of the real sample structure. The ordering of the pores in neighboring domains is distinguished. The pores are contorted and their growth is stopped mainly on the domain borders. The suggested diffraction technique with tunable probe size can be applied successfully for the detail studying of the different nanostructured materials.