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Polycrystalline titaniumnitride (TiN) layers of 240 nmthickness and columnar microstructure were deposited at 150 degrees C by d. c. reactive sputtering on Si(100) wafers and then irradiated at roomtemperature with either 80 keV V+ ions (at fluences of up to 2x10(17) ions/cm(2)) or 200 keV Ar+ ions (at fluences of 5x10(15)-2x10(16) ions/cm(2)). Rutherford backscattering spectroscopy, cross-sectional (high-resolution) transmission electron microscopy and X-ray diffraction were used to characterize ion-induced changes in the structural properties of the films. Their optical and electric properties were analyzed by infrared reflectance (IR) and electric resistivity measurements. After deposition, the stoichiometric TiN films had a (111) texture. Ion implantation generated a damaged surface layer of nanocrystalline structure, which extended beyond the implantation profile, but left an undamaged bottom zone of (111) orientation. This layer geometry determined from transmission electron microscopy was inferred in the analysis of IR reflectance data using the Drude model, and the variation of the electric and optical resistivity with the irradiation was deduced. The results were compared to those recently gained for ion-implanted reactively sputtered chromium nitride films. (C) 2013 Elsevier B.V. All rights reserved.

Studies on ion-irradiated transition-metal/silicon bilayers demonstrate that interface mixing and silicide phase formation depend sensitively on the ion and film parameters, including the structure of the metal/Si interface. Thin Co layers e-gun evaporated to a thickness of 50 nm on Si(1 0 0) wafers were bombarded at room temperature with 400-key Xe(+) ions at fluences of up to 3 x 10(16) cm(-2). We used either crystalline or pre-amorphized Si wafers the latter ones prepared by 1.0-keV Ar-ion implantation. The as-deposited or Xe-ion-irradiated samples were then isochronally annealed at temperatures up to 700 degrees C. Changes of the bilayer structures induced by ion irradiation and/or annealing were investigated with RBS, XRD and HRTEM. The mixing rate for the Co/c-Si couples, Delta sigma(2)/Phi = 3.0(4) nm(4), is higher than the value expected for ballistic mixing and about half the value typical for spike mixing. Mixing of pre-amorphized Si is much weaker relative to crystalline Si wafers, contrary to previous results obtained for Fe/Si bilayers. Annealing of irradiated samples produces very similar interdiffusion and phase formation patterns above 400 degrees C as in the non-irradiated Co/Si bilayers: the phase evolution follows the sequence Co(2)Si - GT CoSi - GT CoSi(2). (C) 2010 Elsevier B.V. All rights reserved.