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Purpose. The aim of this work was atomic and electronic structure and phase composition study of submicron Ni rods arrays formed by electrochemical deposition in a porous SiO2 matrix on crystalline silicon depending on the conditions of their production by the synchrotron technique of X-ray Absorption Near Edge Structure (XANES) in the near-surface layers sensitive registration mode of total electron yield detection and bulk sensitive registration mode of fl uorescence yield detection. Methods and Methodology. Nickel rods arrays were obtained by electrochemical deposition of metal into the pores of the silicon dioxide matrix formed by the ion-tracking technique. Latent tracks were formed by irradiating the SiO2 layer with heavy gold ions at the Han-Meitner Institute accelerator (Berlin, Germany). In the fi rst case, ion fl uence under irradiation was 1·108 cm–2, and etching time was 40 minutes (group A), in the second case ion fl uence was 5·108 cm–2, etching time was 80 minutes (group B). The initial SiO2/Si structures (from the formed oxide layer to the fi nished porous matrix) and Ni/SiO2/Si composite structures were studied using the scanning electron microscopy (SEM) with the use of LEO1455-VP microscope. The surface morphology was studied in the mode of secondary electrons detection. The local atomic and electronic structure in Ni/SiO2/Si composite structures was studied by XANES spectra. XANES were simultaneously recorded by the method of measuring total electron yield and by the fl uorescent photons detection mode. X-ray spectroscopy data were obtained at the Russian German beamline of BESSY II synchrotron of the Helmholtz Zentrum Berlin (Germany). The vacuum in the spectrometers chambers was 10–10 Torr, the instrument broadening was 0.1 eV. When registering TEY, the analysis depth was ~ 10 nm (O K absorption edge) and 15 nm (Ni L2,3 absorption edge). At the same time the depth of analysis for XANES data recording in fl uorescence yield mode exceeds hundreds of nanometers. A pure gold foil signal was used to calibrate and normalize the experimental spectra. The following objects were used as reference objects: SiO2 matrix without nickel fi lling, thermal SiO2 fi lm with thickness of 100 nm, commercial: metallic nickel, nickel oxide NiO, nickel silicide Ni2Si produced by Alfa Aesar. Results. SEM studies have shown effective electrodeposition of nickel in the pores of the oxide layer on crystalline silicon. The direct dependence of the formation effi ciency and density of nickel particles coating (resp. pores) of the composite structure Ni/SiO2/Si is demonstrated from the fl uence of ions as the main parameter of the formation tracks, and the time of electrochemical deposition. However, the metal/semiconductor interface (particle / substrate), the characteristics of which can have a signifi cant effect on the properties of the composite structure, is generally hidden for SEM analysis from the surface at least by the layer thickness of the silicon oxide dielectric matrix.For the phase formation studies in Ni/SiO2/Si composite structures when nickel fi ll the pores of silicon dioxide, it is possible to effectively use the synchrotron XANES method in the “surface-” and “volume-” sensitive modes of the total yield of electrons or fl uorescence yield detection respectively. The obtained data allow us to characterize the specifi cs of the local environment of the atoms included in the nanolayers on the surface of the studied structures, not exceeding 15 nm in the depth of the information layer, and the volume of the same structures, up to micrometers, in a single synchrotron experiment. Conclusions. Electrodeposition of metallic nickel in type a samples (within 40 minutes) into pores formed at fl uence values of 108 ion/cm2 does not lead to a noticeable interatomic interaction on the surface and the “volume” boundaries of the “metal-emiconductor” (metal-substrate) or “metaldielectric” (metal-fi lm). The samples with fi vefold increased pores density and coated with the particles of metallic nickel (with a twofold increase in time of SiO2 fi lms etching) have the considerably stimulated interatomic interactions of strongly etched matrix of silicon dioxide with the deposited nickel. This leads to the formation of Ni2Si silicide in the bulk part of the Ni/SiO2/Si composite structure, and slightly different silicide in the surface nanolayers, that also enables smooth, through the composition, control of the electronic structure of the composite Ni/SiO2/Si. The formation of surface and volume silicides should be taken into account to optimize the transport properties of the structures studied.