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Nickel thin films were deposited to the different thicknesses onto glass substrates using electron-beam glancing angle deposition. The changes in the structural, chemical, and magnetic properties of the films have been investigated. The obtained morphological and microstructural results revealed that the deposited samples consisted of vertical columns with a thickness in the range of 50 nm to 140 nm and a diameter of 15 nm to 29 nm. With the increase in film thickness, the surface roughness increases as well. Chemical analysis showed that the main phase in the samples is metallic Ni, with a certain amount of NiO. In addition, magnetic measurements exhibit that all Ni films show typical hysteresis loops with a uniaxial magnetic anisotropy. The coercivity was found to increase with the thickness up to 110 nm followed by its further decrease, probably due to the differences in the structure of the columns themselves as well as the combined contributions of two different antiferromagnetic (NiO) and ferromagnetic (Ni) phases created in the deposited nanostructures. • Obtaining Ni vertical columns using e-beam glancing angle deposition technique. • Detailed characterization of Ni thin films by AFM, TEM, XPS, MOKE and SQUID methods. • Variations of surface topography, structure and magnetic properties with thickness. [ABSTRACT FROM AUTHOR]

• Sequential Au and Ag ion implantation of 260 nm thick TiN films was performed. • The implantation was done using high ion fluences of Ag (200 keV) and Au (150 keV). • The TiN surface undergoes topographic and chemical changes after ion implantation. • Spherical and crystalline particles with the diameter below 15 nm were formed. • STEM showed that the obtained nanoparticles are Au-Ag alloys. Formation of Au-Ag alloy nanoparticles in TiN thin films is demonstrated through sequential implantation of Au and Ag ions. The irradiations were done with 200 keV Au ions at fluence of 1.0 × 1016 ions/cm2 and 150 keV Ag ions to the fluences in the range of 0.7–1.3 × 1017 ions/cm2. It was found that irradiations introduce around 1.5 at.% of gold and up to ~20 at.% of silver species causing also the significant sputtering of the surface. TiN surface besides the topographic undergoes chemical changes. The presence of silver and gold is confirmed by photoemission spectroscopy showing that the implanted ions did not form any kind of compound with the surrounding matrix. Electron microscopy evidenced the formation of crystalline and quasi-spherical particles with dimensions below 10 nm. Elemental analysis revealed that the obtained nanoparticles present Au-Ag alloys, with two elements mixed over the whole volume of the particles in different Au:Ag ratios. [ABSTRACT FROM AUTHOR]

In the present paper, the effects of metal ion implantation on the structural and optical properties of TiN thin films have been investigated. TiN films of 170 nm thickness were grown by d.c. reactive sputtering on Si (100) wafers and then irradiated at 5 × 1016 ions/cm2 with either Au, Ag, or Cu ions by using two different energies per each implanted metal. The results showed that as deposited TiN crystallizes in the form of a fcc cubic structure, with the crystallites preferentially oriented along the (111) plane. For all implanted layers, the cubic structure was preserved, but compared to as deposited TiN the crystallites were smaller and the lattice was contracted. These changes were correlated with the depth distribution of Au, Ag and Cu ions and assigned to implantation-induced damage that was larger when higher ion energies were used. High-resolution XPS spectra of the surface of as deposited sample showed the coexistence of TiN, TiO 2 and TiO x N y phases and this was related to the surface oxidation of the films due to the exposure to air. After implantation, the results were almost similar for all metals, showing an increase in TiO 2 contribution and the formation of pure metallic Au and Ag phases, while copper is in the Cu2+ state, which is attributed to Cu(II)-oxide and Cu(OH) 2. The microstructural characteristics including defect formation, changes in crystallite size and lattice contraction, and also growth of different metallic phases during implantations were correlated with the findings of the optical characterization of the implanted films. For the as deposited film we found an energy gap of 2.91 eV, which was lower than the value typical for TiN. After implantation the gap was shifted to higher energies, while at the visible part of the region, the existence of additional energy levels, at photon energies below 2.9 eV was observed. Besides, all implanted films showed degraded photocatalytic activity compared to as deposited TiN, among which Cu-implanted samples exhibited the best photocatalytic performances. The lower photocatalytic activity of Au and Ag implanted films compared to Cu implantations was ascribed to larger structural defects and the formation of less favorable electronic states. [Display omitted] • TiN films were modified via metal ion implantation processing. • Ion implantation causes surface degradation and enhances oxidation. • Metal ion implantation promotes reduction of crystallites and contracted lattice. • Incorporation of Au, Ag and Cu ions results in degraded photocatalytic activity. [ABSTRACT FROM AUTHOR]

The present study deals with irradiation effects induced by xenon ions (Xe + ) on titanium nitride (TiN) thin films. TiN films thickness of 260 nm obtained by using dc reactive sputtering were irradiated with 400 keV Xe ions. The irradiation doses were 5 × 10 15 , 10 × 10 15 , 15 × 10 15 and 20 × 10 15 ions/cm 2 . The properties of irradiated films varying with ion fluence are investigated by means of Rutherford backscattering spectrometry, X-ray diffraction, transmission electron microscopy and spectroscopic ellipsometry. It was found that the Xe ions induce contraction and rhombohedral distortion of TiN lattice. The columnar structure was partially destroyed after irradiation, which introduce up to 1.5 at.% of Xe within the structure mostly concentrated around the projected ion range. The generation of defects due to the presence of heavy ions changes the optical constants of implanted films. It was found that the optical band gap of TiN films was reduced after xenon ion implantation. [ABSTRACT FROM AUTHOR]

Titanium nitride (TiN) is an attractive alternative for modern and future photonic applications, as its optical properties can be engineered over a wide spectral range. In this study, we have used sequential implantation of gold and silver ions with varying ion fluence, as well as subsequent annealing, in order to modify the optical and plasmonic properties of TiN thin films and correlated this to their structural properties. Our investigations show that the columnar structure of the TiN films is partially destroyed upon implantation, but metallic Au and Ag nanoparticles are formed. The irradiation further induces a reduction of the lattice constant as well as changes the TiN stoichiometry and grain size. From the optical point of view, the implanted films possess less metallicity with increasing Ag fluence and losses several times lower than the as-deposited film, which can be correlated with the deficiency of nitrogen and additional defects. Subsequent annealing partially recovered the destroyed columnar structure, and the films become more metallic where the optical losses are much smaller in comparison to the as-implanted situation, being comparable to those of pure Au and Ag. In this way, by varying the implantation fluence of silver ions properly while keeping the gold fluence constant, we were able to optimize experimental parameters in such a way to ensure the formation of TiN with desirable optical performances. • TiN is attractive alternative for modern and future photonic applications. • Au/Ag implantation and subsequent annealing is used for modification of TiN films. • Irradiation induces a changes in TiN stoichiometry, lattice constant and grain size. • Both implanted and annealed films are less metallic than as grown TiN film. • After implantation and annealing the optical losses are comparable to Au and Ag. [ABSTRACT FROM AUTHOR]

The present paper investigates the effects of thermal annealing on the structural and magnetic properties of Co thin films. The films were prepared by using electron-beam evaporation method onto Si (100) wafers and annealed in vacuum at 200 °C, 300 °C and 400 °C. A combination of X-ray diffraction, Rutherford backscattering spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectrometry were used to characterize structural properties and the composition of the films, while magnetic behavior was studied by magneto-optical Kerr effect measurements. It was found that as deposited Co layer show predominantly uniaxial magnetic anisotropy, while after annealing at 200 °C and 300 °C a strong influence of fourfold contribution is observed, which is assigned to the thermally induced HCP→FCC phase transition. With further increase in annealing temperature of 400 °C the isotropic contribution becomes the main component of magnetization. Besides, a strong variation in coercive field with annealing temperature was observed, where the coercivity seems to depend closely on the crystallite size. The highest value of H C equals ∼70 Oe and was found for the temperature of 400 °C, where also mixing at the interface has started and formation of CoSi was observed. [Display omitted] ● E-beam evaporated Co thin films were annealed at 200 °C, 300 °C and 400 °C in vacuum. ● At 200 °C and 300 °C HCP→FCC phase transition induces four-fold magnetic anisotropy. ● Beyond 300 °C cobalt thin films exhibit isotropic magnetization. ● Coercivity of Co films depend closely on the crystallite size. ● At 400 °C intermixing has started and formation of thin CoSi layer was observed. [ABSTRACT FROM AUTHOR]

Titanium nitride (TiN) thin films thickness of ∼260 nm prepared by dc reactive sputtering were irradiated with 200 keV silver (Ag) ions to the fluences ranging from 5 × 10 15 ions/cm 2 to 20 × 10 15 ions/cm 2 . After implantation TiN layers were annealed 2 h at 700 °C in a vacuum. Ion irradiation-induced microstructural changes were examined by using Rutherford backscattering spectrometry, X-ray diffraction and transmission electron microscopy, while the surface topography was observed using atomic force microscopy. Spectroscopic ellipsometry was employed to get insights on the optical and electronic properties of TiN films with respect to their microstructure. The results showed that the irradiations lead to deformation of the lattice, increasing disorder and formation of new Ag phase. The optical results demonstrate the contribution of surface plasmon resonace (SPR) of Ag particles. SPR position shifted in the range of 354.3–476.9 nm when Ag ion fluence varied from 5 × 10 15 ions/cm 2 to 20 × 10 15 ions/cm 2 . Shift in peak wavelength shows dependence on Ag particles concentration, suggesting that interaction between Ag particles dominate the surface plasmon resonance effect. Presence of Ag as second metal in the layer leads to overall decrease of optical resistivity of TiN. [ABSTRACT FROM AUTHOR]

The paper reports the study on dielectric functions of TiN films implanted with Ag ions and after annealing at 400 °C and 700 °C, employing spectroscopic ellipsometry technique. By using Drude-Lorentz modelling we have analysed and discussed in detail the evolution of screened and unscreened plasma frequency as well as Drude parameter. In comparison to as deposited film the real part of dielectric constant for Ag-implanted layers exhibits less negative values with increasing ion fluence implying the films possess less metallicity, whereas after annealing TiN becomes more metallic. Simultaneously, after implantation, the imaginary part is more than an order of magnitude lower than for the as deposited TiN and several times lower than that of Au and Ag. The magnitude of imaginary contribution of Ag-implanted TiN films decreases further after subsequent heat treatment at both 400 °C and 700 °C annealing temperatures. Although the differences in stoichiometry and microstructural changes, such as crystallite size, concentration of grain boundaries and defect density were assumed to be the major reason for the variation in optical properties of TiN, spectroscopic ellipsometry data exhibited much stronger effects than expected and indicated some other mechanisms could also be responsible for such behaviour. [Display omitted] • Optical properties of plasmonic TiN thin films were investigated. • TiN was modified by Ag implantation and post-thermal annealing at 400 °C or 700 °C. • Implantation of Ag have a direct consequence on the optical losses of TiN. • After annealing the films exhibit losses lower than those of pure Au and Ag. • Low losses originate from the high values of the Drude broadening parameter. [ABSTRACT FROM AUTHOR]

Highlights: [•] Silicide phases formation in Co/Si system during annealing was investigated. [•] Thin Co films were deposited on crystalline or pre-amorphized Si wafers. [•] Argon ions generate damage region which represents diffusion barrier. [•] The phase sequence depends on the concentration of the reacting species. [•] The observed phase transitions are consistent with predictions of EHF model. [ABSTRACT FROM AUTHOR]

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]

Titanium-nitride (TiN) is known as a very promising plasmonic material, which offers many advantages compared to conventional metals commonly used in practical devices. Despite many improvements, TiN still suffers from high losses in the near-infrared (NIR) spectral region, making it less suitable for real-life applications. In this study, we have investigated the effects of pure silver implanted as well as silver/gold co-implanted TiN thin films on their optical properties, which we analyzed by spectroscopic ellipsometry. We demonstrate that the presence of silver and gold drastically changes both the real and imaginary part of the dielectric function. The implanted films exhibit optical losses several times lower compared to as-deposited TiN. The changes are in particular more pronounced for the samples with Au/Ag co-implantations, reaching nearly the same optical values as those of pure gold and being only slightly larger than that of silver. Thus, such an optical tuning of TiN opens new horizons and provide high potential for its implementation into plasmonic applications. [Display omitted] • Effects of ion implantation on the optical properties of TiN were investigated. • Films were modified either by single Ag implantation or by Au/Ag co-implantations. • Implantation of Au and Ag have a direct consequence on the optical losses of TiN. • Films exhibit losses nearly the same as pure Au and only slightly larger than Ag. • Low optical losses originate from the high values of the Drude broadening parameter. [ABSTRACT FROM AUTHOR]

Copper (Cu) thin films were deposited by using glancing angle deposition in the form of zigzag and square spiral nanostructures. Thin films were fabricated under different azimuthal rotations (φ = 180°, 90°, 45°, 22.5° and 11°), to the thickness of approximately 300 nm. Morphological, chemical and structural properties were investigated by field-emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy. For the optical characterization of the samples spectroscopic ellipsometry was used, while the electrical properties were analyzed by four-point probe method. It was found that as the azimuthal rotation decreases, deposited nanostructures become more porous with larger number of grown arms. Both, optical and electrical analyses revealed that the properties of the obtained thin films are significantly influenced by growth mechanism. By decreasing the φ parameter, the surface plasmon resonance peak was shifted from 1038.9 nm to 1676.6 nm, which can be correlated with the porosity of Cu structures. Besides, it was found that the optical and electrical properties of the thin films are also strongly dependent on the concentration of defects. [Display omitted] • Copper zigzag and square spiral nanostructures obtained by GLAD. • Deposition parameters influence the structural, optical and electrical properties. • SPR peak positioned in the IR part of the spectrum. • Electrical resistivity increases due to increase of defect density. [ABSTRACT FROM AUTHOR]

Abstract: A study of ion beam modification of structural and electrical properties of TiN thin films is presented. The layers were deposited by reactive ion sputtering on (100) Si and glass slide substrates to a thickness of ∼240nm. After deposition the structures were implanted with argon ions at 120keV, to the fluences from 1×1015 to 1×1016 ions/cm2. The ion energy was chosen to give the projected ion range within the deposited layers, to minimize the influence of the substrate on the induced structural changes. Structural analysis of the samples was performed by cross-sectional transmission electron microscopy, X-ray diffraction and Rutherford backscattering spectrometry. Electrical characterization included sheet resistivity measurements with a four point probe. It was found that the as-deposited layers have a columnar structure, individual columns stretching from the substrate to the surface and being a few tens of nanometers wide. Ion irradiation rearranges their crystalline structure, which remains polycrystalline, but the columns are broken, and nanocrystals of the same phase are formed. The structural changes can be nicely correlated to the measured electrical resistivity. [Copyright &y& Elsevier]