Parinova, E.V.; Fedotov, A.K.; Koyuda, D.A.; Fedotova, Y.A.; Streltsov, E.A.; Malashchenok, N.V.; Ovsyannikov, R.; Turischev, S.Y.: The composite structures based on nickel rods in the matrix of silicon dioxide formation peculiarities study using synchrotron XANES in the electrons and photons yield registration modes. Kondensirovannye sredy i mezhfaznye granitsy = Condensed Matter and Interphases 21 (2019), p. 116-125
10.17308/kcmf.2019.21/726
Open Access Version
Abstract:
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 first case, ion fluence under irradiation was 1∙108 cm-2, and etching time was 40 minutes (group A), in the second case ion fluence was 5∙108 cm-2, etching time was 80 minutes (group B). The initial SiO2/Si structures (from the formed oxide layer to the finished 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 fluorescent 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 fluorescence 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 filling, thermal SiO2 film with thickness of 100 nm, commercial: metallic nickel, nickel oxide NiO, nickel silicide Ni2Si produced by Alfa Aesar.