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The present study deals with CrN films irradiated at room temperature (RT) with 200 keV Ar+ ions. The CrN layers were deposited by d.c. reactive sputtering on Si (100) wafers, at nitrogen partial pressure of 5×10-4 mbar, to a total thickness of 280 nm. The substrates were held at 150ºC during deposition. After deposition the CrN layers were irradiated with 200 keV Ar+ ions to the fluences of 5×1015 - 2×1016 ions/cm2. Structural characterization was performed with Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM) and X-ray diffraction (XRD). Spectroscopic ellipsometry measurements were carried out in order to study optical properties of the samples. The irradiations caused the microstructrual changes in CrN layers, but no amorphization even at the highest argon fluence of 2×1016 ions/cm2. Observed changes in microstructure were correlated with the variation in optical parameters. It was found that both refractive index and extinction coefficient are strongly dependent on the defect concentration in CrN layers. [Projekat Ministarstva nauke Republike Srbije, br. III 45005]

This article reports on the formation of iron nitrides during nitrogen ion irradiation of Fe/Si bilayers at room temperature. The 30 nm 57Fe/Si bilayers were prepared by pulsed laser ablation and irradiated with 22 keV N2+ ions at fluences of (0.6–2)×1017 ions/cm2. The structural changes and phases formed by irradiation were analyzed by Rutherford backscattering spectroscopy (RBS), X-ray diffraction analysis (XRD) and conversion electron Mössbauer spectroscopy (CEMS). The results clearly show the formation of several iron nitrides. At the lower fluences, the samples contain a mixture of #x03B5;-Fe2+x N and α-Fe with nitrogen interstitials. For the highest fluence, the paramagnetic #x03B5;-Fe2 N (61%) phase predominated. It can be concluded that the elemental iron almost fully transforms to an iron–nitride layer, but that no iron silicides are formed. [Copyright &y& Elsevier]

Abstract: The present study deals with CrN/Si bilayers irradiated at room temperature (RT) with 120keV Ar ions. The CrN layers were deposited by d.c. reactive sputtering on Si(100) wafers, at different nitrogen partial pressures (2×10−4, 3.5×10−4 and 5×10−4 mbar), to a total thickness of 240–280nm. The substrates were held at room temperature (RT) or 150°C during deposition. After deposition the CrN/Si bilayers were irradiated up to fluences of 1×1015 and 1×1016 ions/cm2. Structural characterization was performed with Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM) and grazing angle X-ray diffraction (XRD). For the highest nitrogen pressure (5×10−4 mbar) a pure stoichiometric CrN phase was achieved. The results showed that Ar ion irradiation resulted in the variation of the lattice constants, micro-strain and mean grain size of the CrN layers. The observed microstructural changes are due to the formation of the high density damage region in the CrN thin film structure. [ABSTRACT FROM AUTHOR]

Abstract: The present study deals with TiN/Si bilayers irradiated at room temperature (RT) with 120 keV Ar ions. The TiN layers were deposited by d.c. reactive sputtering on Si(100) wafers to a thickness of ∼240 nm. After deposition the TiN/Si bilayers were irradiated to the fluences of 1×1015 ions/cm2 and 1×1016 ions/cm2. Structural characterization was performed with Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM), grazing angle X-ray diffraction (XRD) and atomic force microscopy (AFM). The results showed that the variation of the lattice constants, mean grain size and micro-strain can be attributed to the formation of the high density damage region in the TiN film structure. It has been found that this damage region is mainly distributed within ∼100 nm at surface of the TiN layers. [Copyright &y& Elsevier]

Modification in structural, optical and electrical properties of titanium nitride (TiN) thin films induced by argon ion irradiation and thermal annealings was studied using various experimental techniques. TiN thin films deposited by dc reactive sputtering on Si substrate were implanted with argon ions at 200 keV. As-implanted samples were annealed before or after ion irradiation at 600 °C and 700 °C, respectively. Rutherford backscattering spectrometry, X-ray diffraction, cross-sectional (high-resolution) transmission electron microscopy, spectroscopic ellipsometry and electrical measurements were carried out in order to study structural, optical and electrical properties of TiN/Si samples. After irradiation with 200 keV Ar ions the columnar microstructure of TiN was changed and the presence of smaller crystalline grains was observed. Partial loss of columnar structure observed in implanted samples was completely recovered after annealing at 700 °C. Observed changes in microstructure induced by ion irradiation and annealings were correlated with the variation in optical parameters obtained by spectroscopic ellipsometry. It was found that both refractive index and extinction coefficient are strongly dependent on the defects' concentration and size of the crystalline grains in TiN layers. [ABSTRACT FROM AUTHOR]

Thin Fe and Ta layers of 30–45 nm thickness, deposited via magnetron sputtering on Si (1 0 0) substrates, were bombarded at room temperature with 100 keV Ar1+ or Ar8+ or with 250 keV Xe1+ or Xe19+ ions in order to test the influence of the ion charge state on the surface sputtering and interface mixing. The samples were characterized by means of Rutherford backscattering at 0.9–3.0 MeV α-particle energy, time-of-flight elastic recoil detection analysis with a 53 MeV 127I10+ beam and atomic force microscopy. No influence of the charge state on the sputtering and athermal mixing rate was observed in the case of the Ta/Si system. However, in the case of the Fe/Si system, the ion charge was observed to have an influence on the mixing rate. [Copyright &y& Elsevier]

Abstract: This paper reports on a study of microstructrual changes in TiN/Si bilayers due to 200keV Ar+ ions irradiation at room temperature. The 240nm TiN/Si bilayers were prepared by d.c. reactive sputtering on crystalline Si (100) substrates. The TiN films were deposited at the substrate temperature of 150°C. After deposition the TiN/Si bilayers were irradiated to the fluences of 5×1015 and 2×1016 ions/cm2. The structural changes induced by ion irradiation in the TiN/Si bilayers were analyzed by Rutherford Backscattering Spectroscopy (RBS), X-ray diffraction analyses (XRD) and Transmission Electron Microscopy (TEM). The irradiations caused the microstructrual changes in TiN layers, but no amorphization even at the highest argon fluence of 2×1016 ions/cm2. It is also observed that the mean crystallite size decreases with the increasing ion fluence. [Copyright &y& Elsevier]