Search

We measure the center-of-mass diffusion of silica nanoparticles (NPs) in entangled poly(2-vinylpyridine) (P2VP) melts using Rutherford backscattering spectrometry. While these NPs are well within the size regime where enhanced, nonhydrodynamic NP transport is theoretically predicted and has been observed experimentally (2RNP/dtube ≈ 3, where 2RNP is the NP diameter and dtube is the tube diameter), we find that the diffusion of these NPs in P2VP is in fact well-described by the hydrodynamic Stokes–Einstein relation. The effective NP diameter 2Reff is significantly larger than 2RNP and strongly dependent on P2VP molecular weight, consistent with the presence of a bound polymer layer on the NP surface with thickness heff ≈ 1.1Rg. Our results show that the bound polymer layer significantly augments the NP hydrodynamic size in polymer melts with attractive polymer–NP interactions and effectively transitions the mechanism of NP diffusion from the nonhydrodynamic to hydrodynamic regime, particularly at high mole...

The investigation of semiconductor films of undoped ZnO and doped with two weight percentages of Cadmium (0.5 and 3) were grown on glass and silicon substrates under the same conditions using the dip-coating method. The X-ray diffraction patterns showed the growth of the wurtzite ZnO phase in a hexagonal crystal structure. Also, the effect of both cadmium concentration and substrate type is very clear, while the films those grown on glass substrate showed a crystallization with a highly c-axis preferred (002) orientation, those grown on a silicon substrate showed regular growth in all directions of the zinc oxide phase. The average crystallites size is of the nano-metric scale, more precise about 27 nm, supported with images taken with Environmental Scanning Electron Microscopy, furthermore from the latter technic (ESEM), we noticed a presence of three morphological types on the surface, were originated according to the substrate type and quantity of Cd-doping. The Rutherford Backscattering Spectrometry simulation spectra and the Auger Electron Spectroscopy by the relation with the stripping time emphasize the subsistence of starting (Zn) and doping (Cd) elements on the final specimens and in proportional quantities, to deduce that the undoped ZnO specimen thin film is the thickest. All the obtained films have an optical transmission of about 80% level within the visible range and a severe absorption beginning about 370 nm corresponding to the fundamental absorption limit, where the optical band gap energy decreased from 3.21 eV to 3.16 eV for the undoped ZnO and doped with 3 wt.% Cd respectively. The room-temperature luminescence emission spectra of all specimens were excited at the same conditions under 250 nm Xenon lamp excitation, where showed ultraviolet and visible emissions for all the films grown on a glass and silicon substrate, while an opposite reaction was recorded in the intensity of the spectra as the percentage of Cd increased.

Monoclinic BiVO4 (BVO) properties favor its use as the main absorber in photoanodes applied for photoelectrochemical water splitting. However, hindrances as the high rate of recombination of the electrons and holes photogenerated and as the poor charge carrier transport limit its direct, practical use. Doping, building a heterojunction with other semiconductors and decorating the surface with catalysts like cobalt phosphate and ruthenium oxide are among the many existing approaches to improve BVO performance. The deposition of catalyst or cocatalyst normally involve the use of potentially hazardous techniques as chemical vapor deposition (CVD). In this work, we present a simple route for enhancing photoelectrochemical results in BVO samples. The decoration with metallic ruthenium is performed via magnetron sputtering DC, a reliable, inexpensive and safe-to-use physical deposition technique, followed by a thermal treatment in air within a muffle furnace for 6 h at 400 °C. A gain of about 45% in the photocurrent at 1.23 V vs reversible hydrogen electrode (RHE) and in the overall spectrum area in comparison with pristine BVO samples was registered by cyclic voltammetry measurements in a 0.5 M phosphate buffer solution under full spectrum illumination from a 100 W Xenon lamp. The morphological and chemical modifications that resulted in such photocurrent rise were characterized using Scanning Electron Microscopy (SEM), Rutherford Backscattering Spectrometry (RBS) and X-ray Photogenerated Spectroscopy (XPS).

Potassium-tantalate crystals were implanted with helium ions at 190 keV and then thermally treated at different temperatures to study their blistering. The surface blistering, hydrogen depth distribution, and lattice damage induced by He+ implantation were characterized using secondary ion mass spectroscopy, optical and transmission electron microscopy, and Rutherford backscattering spectrometry. The blistering of potassium-tantalate crystals was achieved at certain ion fluences followed by thermal treatment.

We study the absorption of H in ultrathin crystalline Fe/V stacks using elastic recoil detection (ERD) and resonant nuclear reaction analysis (NRA) combined with Rutherford backscattering spectrometry (RBS). Probing with the resonant 1H (15N,αγ) 12C nuclear reaction allows us to profile the hydrogen concentration with high depth resolution, while ERD permits us to quantify the integral hydrogen inventory while minimizing possible ion-beam induced hydrogen desorption. We perform angular scans in order to directly identify the interstitial site occupancy. A detailed analysis of channeling patterns permits us the deduction of crystal strain in as-deposited films as well as H-loaded targets. We observe tetragonal strain formation resulting in c/a = 1.06 and find qualitative indications for tetrahedral site occupation.

The III–V semiconductor GaN is a promising material for photoelectrochemical (PEC) cells, however the large bandgap of 3.45 eV is a considerable hindrance for the absorption of visible light. Therefore, the substitution of small amounts of N anions by isovalent Sb is a promising route to lower the bandgap and thus increase the PEC activity under visible light. Herein we report a new chemical vapor deposition (CVD) process utilizing the precursors bis(N,N′-diisopropyl-2-methyl-amidinato)-methyl gallium (III) and triphenyl antimony (TPSb) for the growth of GaSbxN1−x alloys. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements show crystalline and homogeneous thin films at deposition temperatures in the range of 500–800 °C. Rutherford backscattering spectrometry (RBS) combined with nuclear reaction analysis (NRA) shows an incorporation of 0.2–0.7 at% antimony into the alloy, which results in a slight bandgap decrease (up to 0.2 eV) accompanied by enhanced sub-bandgap optical response. While the resulting photoanodes are active under visible light, the external quantum efficiencies remained low. Intriguingly, the best performing films exhibits the lowest charge carrier mobility according to time resolved THz spectroscopy (TRTS) and microwave conductivity (TRMC) measurements, which showed mobilities of up to 1.75 cm2 V−1 s−1 and 1.2 × 10–2 cm2 V−1 s−1, for each timescale, respectively.

Ion beam sputtering is a versatile technique to create nanostructured thin films with precise control over process parameters. We report the properties of graphitic carbon nitride (g-C3N4) thin films deposited by ion beam sputtering. Ion beam analysis methods including Rutherford Backscattering Spectrometry (RBS), Nuclear Reaction Analysis (NRA) and Particle Induced X-ray Emission (PIXE) were used for quantitative determination of composition, thickness, elemental depth profile and trace, major elements and impurities. It was found that by directly using compressed g-C3N4 powders as the sputter target material and tuning the process parameters, g-C3N4 thin films with well controlled deposition rate were obtained. Post-annealing above 250 °C under argon atmosphere for 30 min was needed to recrystallize the g-C3N4 nanostructure. Our results suggest that ion beam sputtering technique is a promising method to obtain uniform and high-quality g-C3N4 thin films.

The unique structural and electronic properties of transition metal dichalcogenides (TMDs) and in particular tungsten disulphide (WS2) make them interesting for a variety of applications such as the electrocatalytic hydrogen evolution reaction (HER) for water splitting devices and chemiresistive gas sensors. The key parameter for the realisation of these devices is the controlled large-area growth of WS2 combined with tuning the surface morphology and electronic properties which is achieved by bottom-up fabrication methods such as chemical vapour deposition (CVD). In this study, 2H-WS2 films are fabricated by a new metal–organic CVD (MOCVD) process resulting in the growth of crystalline, pure, and stoichiometric films which was accomplished at temperatures as low as 600 °C as confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectrometry (RBS)/nuclear reaction analysis (NRA), and Raman spectroscopy. The surface morphology of WS2 layers was investigated by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM). Following successful process development, the WS2 layers were deposited on conducting FTO/glass substrates and their catalytic activity for the HER was evaluated in a linear sweep voltammetry (LSV) experiment. Furthermore, the temperature-dependent sensor response towards NO2, CO, and NH3 was investigated for WS2 films deposited on special sensor chips, revealing a p-type response towards NO2 and NH3 and sensitivities of around 20% for NO2 and NH3 concentrations of 1.5 ppm and 7.6 ppm, respectively. These promising results demonstrate the effectiveness of scalable CVD-grown WS2 and pave the way for practical applications by modulating the properties of materials to achieve enhanced electrocatalytic and sensing performances employing WS2 layers.

Rutherford Backscattering Spectrometry (RBS) is a powerful ion beam analysis technique in frequent use within materials science. The recent emergence of targets incorporating complex features such as ultra-scaled diffusion barriers and isotopically-enriched films has started to push the limits of the technique, necessitating the expanded use of systems with a higher energy resolution. The increased cost and complexity of these systems based on already well-established schemes may present a barrier to their more widespread adoption. Here, we present an RBS detection system specifically designed for simple integration into existing nuclear probe infrastructure, but with a considerably higher energy resolution than a standard passivated planar detector. We employ a modified silicon p–i–n photodiode integrated within an optimised in-vacuum preamplifier to achieve a relative energy resolution of 3 × 10 −3 with 2.2 MeV He + ions. In a glancing angle geometry, this corresponds to a depth resolution of ∼ 1.5 nm and a mass resolution of 1 u from light elements up to Cu. We demonstrate the use of this detector to measure the thermal diffusion of near-surface As implants in a Si substrate, important for the formation of ultra-shallow junctions; and the residual 29Si concentration in an isotopically enriched 28Si specimen, a promising platform for quantum computation.

Nanorod diffusion in polymer melts is faster than predicted by the continuum model (CM). Rutherford backscattering spectrometry is used to measure the concentration profile of titanium dioxide (TiO2) nanorods (L = 43 nm, d = 5 nm) in a polystyrene (PS) matrix having molecular weights (M) from 9 to 2000 kDa. In the entangled regime, the tracer diffusion coefficients (D) of TiO2 decrease as the M–1.4, whereas the CM predicts DCM ∼ M–3.0 using the measured zero-shear viscosity of TiO2(1 vol %): PS(M) blends. By plotting D/DCM versus M/Me, where Me is the entanglement molecular weight, diffusion is enhanced by a factor of 10–103 as M/Me increases. The faster diffusion is attributed to decoupling of nanorod diffusion from polymer relaxations in the surrounding matrix, which is facilitated by the nanorod dimensions (i.e., L greater than and d less than the entanglement mesh size, 8 nm).

Recent advancements in gallium oxide (Ga2O3)-based heterostructures have allowed optoelectronic devices to be used extensively in the fields of power electronics and deep-ultraviolet photodetection. While most previous research has involved realizing single-crystalline Ga2O3 layers on native substrates for high conductivity and visible-light transparency, presented and investigated herein is a single-crystalline β-Ga2O3 layer grown on an α-Al2O3 substrate through an interfacial γ-In2O3 layer. The single-crystalline transparent conductive oxide layer made of wafer-scalable γ-In2O3 provides high carrier transport, visible-light transparency, and antioxidation properties that are critical for realizing vertically oriented heterostructures for transparent oxide photonic platforms. Physical characterization based on X-ray diffraction and high-resolution transmission electron microscopy imaging confirms the single-crystalline nature of the grown films and the crystallographic orientation relationships among the monoclinic β-Ga2O3, cubic γ-In2O3, and trigonal α-Al2O3, while the elemental composition and sharp interfaces across the heterostructure are confirmed by Rutherford backscattering spectrometry. Furthermore, the energy-band offsets are determined by X-ray photoelectron spectroscopy at the β-Ga2O3/γ-In2O3 interface, elucidating a type-II heterojunction with conduction- and valence-band offsets of 0.16 and 1.38 eV, respectively. Based on the single-crystalline β-Ga2O3/γ-In2O3/α-Al2O3 all-oxide heterostructure, a vertically oriented DUV photodetector is fabricated that exhibits a high photoresponsivity of 94.3 A/W, an external quantum efficiency of 4.6 × 104%, and a specific detectivity of 3.09 × 1012 Jones at 250 nm. The present demonstration lays a strong foundation for and paves the way to future all-oxide-based transparent photonic platforms.

Nanometric YSi2 − x yttrium silicides layers have been formed onto a Si(111) single-crystal substrate by implantation at room temperature (RT) of Y ions using an energy of 195 keV and a dose of 2 × 1017 Y+/cm2 followed by a thermal annealing in a nitrogen atmosphere. The process of the silicidation has been investigated at a function of the annealing temperatures ranging from 600 to 1000 °C for duration of one hour. The characterization of the samples has been performed using X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), and scanning electron microscopy combined with energy dispersive X-ray spectrometer (SEM-EDS) techniques. Studies have shown that the YSi2 − x layer is epitaxially grown on the Si (111) surface, and after thermal annealing at a temperature of 600–1000 °C, no change in the properties of the formed phase is found.

We have implanted xZnF2–(20-x)ZnO–40As2O3–40TeO2 (x = 4 and 20 mol%) glasses with nitrogen ions at different doses. The glass samples were characterized by Rutherford backscattering spectrometry for the concentration depth profiles of the implanted atoms, by SEM analysis for surface morphology, and also by UV–vis absorption spectroscopy. It was observed that in both the glass systems, there is an increase in the values of penetration depth R, projected range Rp, and straggle ΔRp as the N+ implantation dose grows from 5 × 1016 to 5 × 1017 ions/cm2. Scanning electron micrographs show a considerable change in the surface topography between the unimplanted and nitrogen-implanted regions. After nitrogen ion implantation, the transmittance was found to decrease while the absorption edge shifts towards higher wavelength with the increase in the nitrogen implantation doses in both the glass systems. The observed reduction in optical band gap in the both the glass systems can be attributed to the effect of band tailing due to the defects produced during nitrogen implantation.

In this work, the effect of radiation damage on the migration behaviour of europium (Eu) implanted into polycrystalline SiC was investigated. Polycrystalline Silicon Carbide (SiC) substrates were separately implanted with europium (Eu) ions of 270 keV to a fluence of 1 × 1016 cm−2 at room temperature (RT), 350 °C and 600 °C. The samples were thermally annealed at temperatures ranging from 1000 to 1400 °C in steps of 100 °C for 5 h in vacuum. The as-implanted and annealed samples were characterized by Rutherford Backscattering Spectrometry (RBS) to monitor the depth profile of the implanted Eu, Scanning Electron Microscopy (SEM) and Raman spectroscopy to monitor surface morphology and structural changes respectively. Raman results indicated that a full amorphization was achieved in the room temperature implanted samples but not in the 350 and 600 °C implanted samples. The radiation damage gradually annealed out with increasing annealing temperature in all implanted samples; however, the full re-crystallization was not achieved up to the highest temperature. The broadening of Eu depth profile indicated some diffusion mechanism taking place in the room temperature implanted sample up to 1300 °C annealing temperature was observed. The diffusion coefficients were determined as 0.015, 0.033 and 0.035 nm2/s for samples annealed at 1000 °C, 1100 °C and 1200 °C, respectively. The 350 °C implanted sample indicated a similar form of diffusion mechanism taking place after annealing at 1000 °C, with no further peak broadening taking place at higher temperatures. A diffusion coefficient of 0.019 nm2/s was obtained at this temperature. A diffusion behaviour due to broadening after annealing at 1100 °C and higher temperatures was also observed in the 600 °C implanted sample which retained most of the implanted Eu. Due to the error limit of our RBS system, no reliable diffusion coefficients could be extracted for this sample.

Nickel-based nanostructured materials have gained widespread attention, particularly for energy-related applications. Employing chemical vapor deposition (CVD) for NiO necessitates suitable nickel precursors that are volatile and stable. Herein, we report the synthesis and characterization of a series of new nickel β-ketoiminato complexes with different aliphatic and etheric side chain substitutions, namely, bis(4-(isopropylamino)-pent-3-en-2-onato)nickel(II) ([Ni(ipki)2], 1), bis(4-(2-methoxyethylamino)pent-3-en-2-onato)nickel(II) ([Ni(meki)2], 2), bis(4-(2-ethoxyethylamino)pent-3-en-2-onato)nickel(II) ([Ni(eeki)2], 3), bis(4-(3-methoxy-propylamino)-pent-3-en-2-onato)nickel(II) ([Ni(mpki)2], 4), and bis(4-(3-ethoxypropylamino)pent-3-en-2-onato)nickel(II) ([Ni(epki)2], 5). These compounds have been thoroughly characterized with regard to their purity and identity by means of nuclear magnetic resonance spectroscopy (NMR) and electron impact mass spectrometry (EI-MS). Contrary to other transition metal β-ketoiminates, the imino side chain strongly influences the structural geometry of the complexes, which was ascertained via single-crystal X-ray diffraction (XRD). As a result, the magnetic momenta of the molecules also differ significantly as evidenced by the magnetic susceptibility measurements employing Evan's NMR method in solution. Thermal analysis revealed the suitability of these compounds as new class of precursors for CVD of Ni containing materials. As a representative precursor, compound 2 was evaluated for the CVD of NiO thin films on Si(100) and conductive glass substrates. The as-deposited nanostructured layers were stoichiometric and phase pure NiO as confirmed by XRD, Rutherford backscattering spectrometry (RBS), and nuclear reaction analysis (NRA). X-ray photoelectron spectroscopy (XPS) indicated the formation of slightly oxygen-rich surfaces. The assessment of NiO films in electrocatalysis revealed promising activity for the oxygen evolution reactions (OER). The current densities of 10 mA cm-2 achieved at overpotentials ranging between 0.48 and 0.52 V highlight the suitability of the new Ni complexes in CVD processes for the fabrication of thin film electrocatalysts.

A novel Rutherford backscattering spectrometry (RBS) method is presented to investigate the interface between a solid surface and a surrounding liquid. The introduced measurement system allows to observe and quantify adsorption at the solid–liquid interface and the formation of the electrochemical double layer (EDL). BaCl2 as a bicomponent electrolyte and a Si3N4 membrane surface are chosen as a model system to prove the capabilities of the setup. The results of these RBS measurements are combined with electrochemical impedance spectroscopy (EIS) to validate the findings for the solid–liquid interface under study. Complementary results and discrepancies regarding the formation of the EDL are discussed. Author keywords: electrochemical double layer, electrochemical impedance spectroscopy, Rutherford backscattering spectroscopy, silicon nitride

Active radiation environments and high-rate backgrounds pose a significant challenge towards improving the detection and characterization of Special Nuclear Material (SNM) using Associated Particle Imaging (API). Ongoing research seeks to reduce the sensitivity of a charged particle, or associated particle, detector to x-ray backgrounds through the creation and characterization of an alpha-sensitive, Ce-doped surface region of Yttrium Aluminium Perovskite (YAP). A wet-chemical layer of trivalent cerium (III) acetylacetonate hydrate was thermally diffused with a reducing atmosphere into single YAP crystals for a temperature range of 800 °C to 1500 °C. The diffusion concentration profile of the cerium compound was assayed with Rutherford Backscattering Spectrometry (RBS), where the Ce diffusion activation energy and the pre-exponential factor within YAP were found to be 1.02 ± 0.10 eV and 9.7 ± 2.0 × 10 - 15 m 2 s - 1 , respectively. Resulting transient polycrystalline structural features at the surface of the YAP crystals were investigated with X-Ray Diffraction (XRD). YAP, Yttrium Aluminium Garnet (YAG), and Yttrium Aluminium Monoclinic (YAM) phases were identified, as well as contributions from Y2O3, CeO2, Ce2O3, and the metastable hexagonal polymorph of YAlO3 (YAH). The luminescent responses of the complex surface layers to x-ray and α excitement were examined as functions of annealing temperature. Radioluminescence emissions typical of the Ce3+ 4f → 5d transition occupying both the Y3+ and Al3+ sites in YAP and YAG were observed. The brightness of the samples under alpha radiation increased as a function of diffused Ce concentration until the point of optical darkening.

Au-Ag alloy nanoparticles were formed into amorphous silicon by sequential ion implantation of Au and Ag. Monocrystalline Si was amorphized at the initial moment of implantation with 1 × 1016 ions/cm2 gold ions, and then different silver fluences were applied in the range of 1 × 1016–1 × 1017 ions/cm2. After implantations the samples were investigated by means of Rutherford backscattering spectrometry and transmission electron microscopy. The nanoparticles were found to be formed at surface and sub-surface regions of the Si substrate, at depths corresponding to the maximum distribution of Au and Ag ions. The particles are crystalline in nature with sizes from 2 nm to 30 nm in diameter, increasing with silver ion fluence. Although the lattice constants of gold and silver are too close to be distinguished by measuring the characteristic interplanar spacings, imaging in scanning transmission mode confirms the formation of Au-Ag bimetallic nanoparticles, presenting a solid-solution alloy of gold and silver.

The effect of the sequential implantation of C+ and Ti+ ions on the microstructure and tribophysical properties of smooth crystalline silicon surfaces (c-Si) is evaluated. Microstructural characterization of the samples was performed by scanning electron microscopy, grazing incidence X-ray diffraction and by Rutherford backscattering spectrometry. The surface free energies of the implanted surfaces were also determined and their nanotribological response was evaluated by atomic force microscopy (AFM). It is shown that the sequential implantation of these ions, followed by annealing treatments at proper temperatures, results in thin modified nanolayer formed by a dense dispersion of SiC and TiSi2 nanoparticles in a recrystallized Si matrix that leads to a decrease of the surface energy of the samples, with enhanced nanowear response. These results strongly suggest that this approach can be used to improve the surface properties of Si wafers enlarging its application performance, namely in what concerns NEMS and MEMS devices.

Si(111) substrates, having more atoms available at the surface, are currently being exploited for nano-device fabrication. Epitaxial recrystallization of Si(111) layers amorphized under 80 ...

Ion beam analyses were completed on single crystal LiD (lithium hydride with deuterium on the hydrogen sites) to determine products of hydrolysis with decarbonated H2O (with protium-hydrogen) in an inert gas. Rutherford backscattering spectrometry showed movement of oxygen into the bulk of LiD samples. Hydrolysis rates for the single crystal LiD showed relatively slow initial growth of an oxygen-containing layer. Final growth rates varied widely with H2O level, from 1010 to 1015 (atoms/cm2)/min. at 5.6 and 28 mmol/min. H2O respectively. Simulations of spectra show the hydrolysis product to be LiOH. Elastic recoil detection identifies the hydrogen in the hydroxide layer upon dosing with H2O (with natural, protiated hydrogen) as primarily protium. Micrographs showed island growth occurring initially, with convergence to a full-coverage hydrolysis layer.

The specimens of nanostructured semiconductor of Zn1-xCdxO (0 ≤ x ≤ 0.1) thin films were grown on silicon substrate using a dip-coating method. The sol-gel technique was used. The appropriate amounts of Zinc acetate dihydrate (ZnAc) and the Cadmium acetate dihydrate (CdAc) were mixed according to the weight ratios that we have identified as follows; 0, 1, 2, 5 and 10 wt.%, then dissolved in 2-Methoxyethanol. Moreover, the Ethanolamine acts as a stabilizer. All films were annealed for 2 h at 500 °C. In order to search the Cd doping effect and its behavior to understand the morphological, structural and optical characteristics with confirm the presence of components and calculate its atomic percentages, we were used many nuclear techniques. The X-ray patterns of all films have showed a hexagonal structure crystallization of wurtzite ZnO phase with nano-metric crystallites size, about 25 nm, confirmed by an Environmental Scanning Electron Microscopy (ESEM) images, also we observed the fibers or a roots-like morphology on the surface. The Auger Electron Spectroscopy (AES) by the relation with the etching time and the Rutherford Backscattering Spectrometry (RBS) simulation spectra confirmed the existing of starting and doping elements, to conclude in the latter that the sample of ZnO film doped 10 wt.% Cd has the thickest. Regarding the Photoluminescence (PL) property and under the excitation of 250 nm by Xenon lamp in the room-temperature, the films showed a luminescence spectra of ultraviolet and visible emission, and we remarked also an increasing intensity of this latter up to 5 wt.% Cd doping, as well as a decrease of the optical gap energy has been registered from 3.33 to 3.25 eV with the increase of cadmium doping concentration.

Copper-doped silica films have been deposited on amorphous silica (fused quartz) by magnetron co-sputtering. The resulting films were characterized for copper loading/thickness by Rutherford backscattering spectrometry, and the optical properties were evaluated by absorption and photoluminescence spectroscopies. The films were subjected to thermal treatment under a 5% H2−95% Ar-reducing atmosphere and further evaluated for surface plasmon resonance (SPR) characteristics. In addition, the occurrence of Cu nanoparticles (NPs) was evaluated by transmission electron microscopy. It is indicated that the films have effective permeability for H2, and consequently, the reduction of ionic copper takes place supporting the nucleation and growth of Cu NPs. Interestingly, along with the increase in absorption intensity of Cu NPs, the processing leads consistently to significant blue shifts in the SPR peaks. Absorption spectra were then simulated by Mie theory calculations for dielectric-embedded Cu NPs in an effort to understand the influence of particle size and medium refractive index on the SPR.

Tungsten-oxide-based thin films were prepared by reactive DC magnetron sputtering in the presence of oxygen and nitrogen. Nitrogen contents up to 12 at.% were documented by Rutherford backscattering spectrometry and time-of-flight elastic recoil detection analysis. Optical and electrochemical measurements showed that films with up to 4 at.% of nitrogen were as transparent as undoped tungsten oxide films and displayed enhanced electrochromic properties manifested in an increase in the coloration efficiency by as much as 20%.

The formation of damage in neodymium doped calcium niobate gallium garnet was investigated after irradiation with 100 keV and 6 MeV C ions at room temperature. The damage was quantified by means of Rutherford backscattering spectrometry in channelling configuration (RBS/C). In order to cope with the superposition of the signal from Nb, Ga and Ca atoms, a special procedure was developed to reconstruct RBS/C spectra yielding the depth distribution of damage. For 6 MeV C ions, the high electronic energy loss of the ions significantly contributes to damage formation. In the nuclear regime, at low ion fluences, point defects are produced. Nucleation and growth of a second type of damage finally results in an amorphous layer. The final damage state is stable up to 600 °C. At 700 °C part of the implanted layer recrystallizes. Annealing at 800 °C decreases the remaining damage concentration from 100% to about 70%.

We have calibrated on-site WD-XRF (wavelength-dispersive X-ray fluorescence) measurements of GeSbTe:N (GST:N) stoichiometry with off-site accurate ion beam analysis (IBA). N is determined by elastic backscattering spectrometry (EBS) using the resonance at 3.7 MeV in the 14N(a, a)14N reaction. Ge and Sb+Te are determined by Rutherford backscattering spectrometry (RBS) separately but self-consistently with the resonant EBS: the Sb/Te ratio can be determined by RBS but not with useful precision. The XRF instrumental function is determined using pure metal standards and the spectra are quantified using Fundamental Parameters code. We find that, as expected, for both Ge and (Sb+Te) the heavy elements are determined accurately by XRF (within the uncertainties), but for N the standardless XRF has non-linear errors around 10%. Using the absolute N content determined by IBA a calibration curve is obtained allowing N determination by WD-XRF at a precision of about 1% and an absolute accuracy (traceable through IBA) of about 4 % for GST films with N content between 4-20 at%. The IBA measurement precision of the N content of the GST-N XRF calibration samples is 0.4 at% (that is, a relative precision ranging from 10 % to 2 % for N contents between 4-20 at%).

Radioactive $^{233}$U alpha recoil sources are being considered for the production of a thorium ion source to study the low-energy isomer in $^{229}$Th with high-resolution collinear laser spectroscopy at the IGISOL facility of the University of Jyv\"askyl\"a. In this work two different $^{233}$U sources have been characterized via alpha and gamma spectroscopy of the decay radiation obtained directly from the sources and from alpha-recoils embedded in implantation foils. These measurements revealed rather low $^{229}$Th recoil efficiencies of only a few percent. Although the low efficiency of one of the two sources can be attributed to its inherent thickness, the low recoil efficiency of the second, thinner source, was unexpected. Rutherford backscattering spectrometry (RBS) was performed to investigate the elemental composition as a function of depth revealing a contamination layer on top of the thin source. The combination of spectroscopic methods proves to be a useful approach in the assessment of alpha recoil source performance in general., Comment: 10 pages, 12 figures, 1 table, submitted to Nuclear Instruments and Methods B, EMIS 2018

[EN] We study the nanopatterning of silicon surfaces under near-normal 40-keV Ar+ sputtering with simultaneous Fe oblique codeposition. The ion-beam incidence was kept at 15°, for which no pattern is produced in the absence of metal incorporation. Morphological and compositional analyses were performed by atomic force microscopy, in its morphological and electrical modes, Rutherford backscattering spectrometry, X-ray photoelectron spectroscopy, scanning Auger, as well as transmission and scanning electron microscopy. Initially, nanodot structures randomly emerge, which, with increasing ion fluence, become progressively aligned along the perpendicular direction to the Fe flux. With increasing fluence, they coalesce, leading to a ripple pattern. The pattern dynamics and characteristics are faster and enhanced, respectively, as the distance to the metal source decreases (i.e., as the metal content increases). For the highest metal flux, the ripples can become rather large (up to 18 μm) and straighter, with few defects, and a pattern wavelength close to 500 nm, while keeping the surface roughness close to 15 nm. Furthermore, for a fixed ion fluence, the pattern order is improved for higher metal flux. In contrast, the pattern order enhancement rate with ion fluence does not depend on the metal flux. Our experimental observations agree with the predictions and assumptions of the model by Bradley [R. M. Bradley, Phys. Rev. B 87, 205408 (2013)10.1103/PhysRevB.87.205408] Several compositional and morphological studies reveal that the ripple pattern is also a compositional one, in which the ripple peaks have a higher iron silicide content, in agreement with the model. Likewise, the ripple structures develop along the perpendicular direction to the Fe flux, and the pattern wavelength increases as the metal flux decreases with a behavior qualitatively consistent with the model predictions., This research is supported by Spanish MINECO (Grants No. MAT2016-80394-R and No. MAT2017-85089-C2-1R) and the TRANSNANOAVANSENS program (Grant No. S2018/NMT-4349) from the Comunidad de Madrid. A.R.C. acknowledges Ramón y Cajal program (under Contract No. RYC-2015-18047). F.J.P. is thankful for financial support by A.E. Consejo Superior de Investigaciones Científicas (under Grant No. CSIC-2019AEP150). The use of HZDR Ion Beam Center TEM facilities is gratefully acknowledged.

Zirconium nitrate (ZrN) layers of about 20 µm were deposited onto silicon (Si) substrates at room temperature (RT) using a vacuum arc deposition technique. Some of the as-deposited samples were irradiated with Eu (360 keV) to a fluence of 1.0 × 1016 cm−2 at RT. Others were irradiated with 167 MeV Xe ions to the fluence of 6.7 × 1014 cm−2 at RT. Both Eu and Xe irradiated samples were annealed at 800 and 900 °C for 5 h. The as-deposited samples were characterised by X-ray diffraction (XRD) and Raman spectroscopy while irradiated and annealed samples were characterised by Raman spectroscopy and Rutherford backscattering spectrometry (RBS). XRD results showed (1 1 1), (2 0 0), (3 1 1) and (2 2 2) planes of ZrN confirming the polycrystalline nature as-deposited layers Raman results of as-deposited ZrN showed all vibration modes indicating ZrN with defects. Irradiation with slow ions resulted in the accumulation of defects in the irradiated samples. Fewer defects were observed in the swift heavy ions irradiated samples. Thermal annealing at 800 and 900 °C resulted in different stoichiometric structures of ZrN with broken octahedral symmetry. No migration of implanted Eu was observed after annealing at these temperatures.

Pd(50 nm)/Ti(25 nm)/Pd(50 nm) multilayer stack has been deposited on Ti and Ti6Al4V substrates; we have studied the intermixing of layers upon annealing at the hydrogenation temperature of 550 °C, under vacuum, H/Ar gas mixture and pure hydrogen atmospheres. Scanning electron microscopy (SEM) micrographs indicated surface roughening in samples annealed under vacuum and H/Ar gas mixture while those annealed under pure H2 remained relatively smoother. Rutherford backscattering spectrometry (RBS) revealed intermixing of layers as evidenced by the diffusion of Pd toward the bulk, while XRD indicated the formation of PdTi2 phase in the samples annealed under vacuum and H/Ar gas mixture atmosphere. In-situ, real-time RBS showed that the annealing under pure H2 preserves the integrity of the Pd catalyst. No indication of the PdTi2 formation in the pure H2 annealed samples was observed; instead only the TiH2 phase appeared, indicating the absorption of H into the system.

Surface decoration by means of metal nanostructures is an effective way to locally modify the electronic properties of materials. The decoration of ZnO nanorods by means of Au nanoparticles was experimentally investigated and modelled in terms of energy band bending. ZnO nanorods were synthesized by chemical bath deposition. Decoration with Au nanoparticles was achieved by immersion in a colloidal solution obtained through the modified Turkevich method. The surface of ZnO nanorods was quantitatively investigated by Scanning Electron Microscopy, Transmission Electron Microscopy and Rutherford Backscattering Spectrometry. The Photoluminescence and Cathodoluminescence of bare and decorated ZnO nanorods were investigated, as well as the band bending through Mott–Schottky electrochemical analyses. Decoration with Au nanoparticles induced a 10 times reduction in free electrons below the surface of ZnO, together with a decrease in UV luminescence and an increase in visible-UV intensity ratio. The effect of decoration was modelled with a nano-Schottky junction at ZnO surface below the Au nanoparticle with a Multiphysics approach. An extensive electric field with a specific halo effect formed beneath the metal–semiconductor interface. ZnO nanorod decoration with Au nanoparticles was shown to be a versatile method to tailor the electronic properties at the semiconductor surface.

Nanostructured photoactive systems are promising for applications such as air and water purification, including self-cleaning coatings. In this study, mesoporous TiO2 sol-gel coatings with different pore structures were prepared and modified with silver by two methods: the “mixing” method by adding AgNO3 to the precursor sol, and the “impregnation” method by immersing the samples in AgNO3 solution (0.03 and 1 M) followed by heat treatment. Our aim was to investigate the effects that silver modification has on the functional properties (e.g., those that are important for self-cleaning coatings). Transmittance, band gap energy, refractive index, porosity and thickness values were determined from UV-Vis spectroscopy measurements. Silver content and structure of the silver modified samples were characterized by X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, High-resolution transmission electron microscopy and Energy Dispersive X-ray Spectrometry elemental mapping measurements. Wettability properties, including photoinduced wettability conversion behavior were investigated by water contact angle measurements. Photoactivity was studied under both UV and visible light with rhodamine 6G and methylene blue dye molecules, at the liquid–solid and air–solid interfaces modeling the operating conditions of self-cleaning coatings. Samples made with “impregnation” method showed better functional properties, in spite of their significantly lower silver content. The pore structure influenced the Ag content achieved by the “impregnation” method, and consequently affected their photoactivity.

We studied the uptake of deuterium (D) into tungsten (W) through thin films of W oxide. Two surface oxide films with thicknesses of 33 and 55 nm were thermally grown on W substrates. In the following, the oxidized samples were exposed to low-energy D (5 eV/D) from a D plasma at a sample temperature of 370 K. A defect-rich layer of self-damaged W underneath the oxide was used as a getter layer to enable the detection of D that penetrates the oxide film. Depth-resolved concentration profiles of D and oxygen (O) were obtained after the plasma exposure by nuclear reaction analysis and Rutherford backscattering spectrometry. We have found that oxygen is partially removed from the first 100 × 1019 atoms/m2 (≈ 13.5 nm) of the oxide film by the D plasma which leads to a W enrichment in the near surface region. Independent of the oxide thickness, an oxygen removal rate of (5.4 ± 0.7) × 10−4 O atoms per incident D atom was observed. Furthermore, D accumulates in the oxide film to concentrations of up to 1.3 at. %, but does not penetrate into the underlying self-damaged W. After a storage period of ten months at room temperature in vacuum, the D content in the oxide layer has decreased substantially, but still no D has penetrated into the metallic W. It is evident that surface oxide films on W effectively block the D uptake into metallic W. However, the D uptake into metallic W is not limited by the transport in the oxide film itself. D diffuses fast throughout the oxide but is stopped at the interface to the metallic W. We attribute this behavior to the difference in the heat of solution for D in W oxide and metallic W. D cannot overcome this barrier once it is thermalized to 370 K within the W oxide film.

Stopping power and energy loss straggling data of 4He+ swift ions in Bismuth thin film (Bi/Si) deposited onto silicon substrate were measured via Rutherford backscattering spectrometry (RBS) at incident energies ranging from 0.9 to 3.0 MeV. We adopted an improved experimental method based on the Kr+ ion implantation of the target Si substrate at low 40 keV energy and using the generated Kr-peak in the backscattered RBS spectra as reference to extract both the energy loss and the energy loss straggling for He+ ions crossing the Bi thin film. The obtained experimental stopping power values were found in good agreement with those generated numerically via SRIM-2013 and CasP 5.2 computer codes. They are also showed to be consistent with previously reported stopping data within the He+ ion energy region mainly below 1.5 MeV, which are thus extended them to higher incident energies. Finally, the relevance of collisional straggling values predicted by Bohr’s and Bethe-Livingston’s theories for describing the determined experimental straggling data was discussed by invoking two main additional contribution effects due to target thickness inhomogeneity and ion charge exchanges included in the Yang semi-empirical formula.

Catalytic layers on the surface of Toray Carbon Fiber Paper TGP-H-060 T and AVCarb® Carbon Fiber Paper P50 carbon carriers are formed by the ion-beam-assisted deposition of platinum and rare-earth-metal gadolinium (as an activating additive) in order to obtain electrocatalysts for the direct oxidation of ethanol and methanol for fuel cells with a polymer membrane electrolyte. The formation of the layers is carried out in the ion-beam-assisted deposition mode, in which metal deposition and mixing of the deposited layer with the substrate surface with accelerated (U = 5 kV) ions of the same metal are carried out, respectively, from the neutral fraction of the vapor and plasma of a vacuum pulsed arc discharge. The microstructure and composition of the obtained surface layers are studied using scanning electron microscopy, electron probe X‑ray spectral microanalysis, X-ray fluorescence analysis, and Rutherford backscattering spectrometry. As a result of the ionic mixing of all components, multicomponent layers containing atoms of precipitated metals and substrate elements, as well as oxygen impurities, are obtained.

We present an atomic layer deposition (ALD) process for the synthesis of tin nitride (SnNx) thin films using tetrakis(dimethylamino) tin (TDMASn, Sn(NMe2)4) and ammonia (NH3) as the precursors at low deposition temperatures (70-200 °C). This newly developed ALD scheme exhibits ideal ALD features such as self-limited film growth at 150 °C. The growth per cycle (GPC) was found to be ∼0.21 nm/cycle at 70 °C, which decreased with increasing deposition temperature. Interestingly, when the deposition temperature was between 125 and 180 °C, the GPC remained almost constant at ∼0.10 nm/cycle, which suggests an ALD temperature window, whereas upon further increasing the temperature to 200 °C, the GPC considerably decreased to ∼0.04 nm/cycle. Thermodynamic analysis via density functional theory calculations showed that the self-saturation of TDMASn would occur on an NH2-terminated surface. Moreover, it also suggests that the condensation of a molecular precursor and the desorption of surface *NH2 moieties would occur at lower and higher temperatures outside the ALD window, respectively. Thanks to the characteristics of ALD, this process could be used to conformally and uniformly deposit SnNx onto an ultranarrow dual-trench Si structure (minimum width: 15 nm; aspect ratio: ∼6.3) with ∼100% step coverage. Several analysis tools such as transmission electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, and secondary-ion mass spectrometry were used to characterize the film properties under different deposition conditions. XRD showed that a hexagonal SnN phase was obtained at a relatively low deposition temperature (100-150 °C), whereas cubic Sn3N4 was formed at a higher deposition temperature (175-200 °C). The stoichiometry of these thermally grown ALD-SnNx films (Sn-to-N ratio) deposited at 150 °C was determined to be ∼1:0.93 with negligible impurities. The optoelectronic properties of the SnNx films, such as the band gap, wavelength-dependent refractive index, extinction coefficient, carrier concentration, and mobility, were further evaluated via spectroscopic ellipsometry analysis. Finally, ALD-SnNx-coated Ni-foam (NF) and hollow carbon nanofibers were successfully used as free-standing electrodes in electrochemical supercapacitors and in Li-ion batteries, which showed a higher charge-storage time (about eight times greater than that of the uncoated NF) and a specific capacity of ∼520 mAh/g after 100 cycles at 0.1 A/g, respectively. This enhanced performance might be due to the uniform coverage of these substrates by ALD-SnNx, which ensures good electric contact and mechanical stability during electrochemical reactions.

Tungsten nitride (WNx) thin films were deposited on SiO2 substrates by atomic layer deposition (ALD) using a fluorine- free tungsten metal-organic precursor of tris(3-hexyne) tungsten carbonyl, W(CO)(CH3CH2C ≡ CCH2CH3)3 and NH3 plasma as a reactant at a deposition temperature of 250 °C. Important ALD characteristics, such as self-limiting growth and linear dependency of the film growth on the number of ALD cycles, were obtained with a growth rate of 0.045 nm/cycle. The minimum film resistivity of around ~2800 μΩcm (thickness: ~ 13.3 nm) was stable after 3 days air-exposure, indicating the high stability of these WNx films. Rutherford backscattering spectrometry showed that the N-rich WNx thin films (N/W ratio: ~ 1.56) were deposited with negligible impurities of C and O. Both X-ray diffractometry and transmission electron microscopy analysis showed that ALD-WNx films formed a polycrystalline cubic WN phase with an average grainsize of ~ 6 nm. From scanning Kelvin probe analysis, its work function was determined as 4.79 eV. Detail investigations were carried out after post-annealing of the as-deposited films and formation of metallic-W with significantly reduced sheet resistance was observed upon annealing at and beyond 700 °C. Finally, the ultrathin (~5 nm) ALD-grown WNx film effectively prevented diffusion of Cu even up to 550 °C, promising it as an efficient diffusion barrier material for the Cu interconnect.

We present a method using resonant nuclear reaction analysis combined with optical transmission and heavy-ion Rutherford backscattering spectrometry to study the absorption of hydrogen in single crystalline thin vanadium films. Probing with the resonant 1H(15N,αγ)12C reaction allows for highly resolved hydrogen depth profiling, while measurements along the crystal axes render possible the direct identification of the interstitial site occupancy. First experiments were performed on thin vanadium hydrides in Fe(Cr)/V superlattices revealing differences in site occupancy.

Sandwiched 142 , 150 Nd targets of thickness ( ∼ 100– 150 μ g /cm 2 ) have been fabricated between two carbon layers of different thickness ( ∼ 30 μ g /cm 2 and ∼ 10 μ g /cm 2 ) using the thermal evaporation technique in the diffusion pump based coating unit at the target lab of Inter University Accelerator Center (IUAC), New Delhi. Thickness and purity measurement of the targets have been confirmed by using the Rutherford backscattering spectrometry (RBS) technique and energy dispersive X-ray fluorescence (EDXRF) measurement present at IUAC, New Delhi and Panjab University, Chandigarh, respectively. These targets have been successfully used in a recent experiment to measure evaporation-residue (ER) cross section and spin distribution of ERs in the hybrid recoil mass analyzer (HYRA) facility present at IUAC.

A Nd:YAG laser operating at 1064 nm was used to irradiate, at different intensities, graphene oxide foils placed in vacuum and in air. The laser irradiated GO foils were analysed successively by using different techniques such as 2.0 MeV alpha particle Rutherford backscattering spectrometry, X-ray photoemission spectroscopy and SEM-EDX. In particular, in vacuum irradiated graphene oxide samples the oxygen reduction has been observed with increment of the carbon content. In air irradiated GO samples an increase in oxygen has instead been highlighted. Furthermore thermal and chemical effects are induced by the photon irradiation. Results will be presented and discussed.

We quantitatively investigated the thickness fluctuation in nanometer order observed in an ultrathin silicon-on-insulator (SOI) film separated by a shallow oxygen ion implantation in a silicon substrate by classical Rutherford backscattering spectrometry (RBS). We first show that the interfacial fluctuation in nanometer scale cannot be identified by the conventional RBS with high-energy MeV He ions due to poor depth resolution. We then explore the possibility of the improvement in the depth resolution by using the primary ions of relatively heavy 10B projectiles combined with a grazing geometry. As a result, we confirmed the ability to quantify the thin fluctuation in a few nanometers by the classical RBS method using 10B ions. We applied the technique to investigate the evaluation of the interfacial fluctuation in several nanometers at ultrathin SOI/BOX structure synthesized by low-energy separation by implanted oxygen (SIMOX) method. The interfacial roughness estimated by the present RBS was consistent with that estimated by the cross-sectional TEM image in advance.

The influence of swift heavy ions (SHIs) irradiation on the microstructure and the migration behavior of strontium (Sr) implanted into polycrystalline SiC were investigated using Rutherford backscattering spectrometry (RBS), Raman spectroscopy and scanning electron microscopy (SEM). The as-implanted and SHIs irradiated samples were vacuum annealed from 1100 to 1500 °C in steps of 100 °C for 5 h. Implantation of strontium (Sr) amorphized the SiC, while SHIs irradiation of the as-implanted SiC resulted in limited recrystallization of the initially amorphized SiC. Annealing at 1100 °C already caused recrystallization in both the irradiated and un-irradiated but implanted with Sr samples. At 1500 °C, a carbon layer appeared on the surface of the irradiated and un-irradiated but implanted with Sr samples. This was due to the decomposition of the SiC and subsequent sublimation of silicon leaving a free carbon layer on the surface. SHIs irradiation alone induced no change in the implanted Sr. Annealing the samples at 1400 °C caused a release of all implanted strontium in the SHIs irradiated samples, while 55% of implanted strontium was released in the un-irradiated but implanted with Sr samples. The enhanced Sr releasing in SHIs irradiated samples was explained in terms of the high number of pores in the irradiated samples compared to fewer pores in the un-irradiated but implanted with Sr samples. The results show that more Sr was released in the irradiated SiC samples.

Inertial Confinement Fusion (ICF) is one of the most important frontier research now. In ICF experiment, fusion fuel like deuterium, tritium, helium is filled into an ICF pellet and heated by lasers directly or indirectly to initiate nuclear fusion reaction. Before every experiment, the amount of fusion fuel in ICF pellets should be accurately determined to analyze the result. However, the amount of fuel gas in the target is so little that it’s not easy to measure. As a high sensitive analysis method, Rutherford Backscattering Spectrometry (RBS) could be used to measure the low amount of gas in ICF pellet, but is still confronted with the difficulty that fuel gas will leak from the pellet so that it can’t be measured in vacuum. Besides, a fast measurement method is needed because the fusion fuel in some pellets has a high leakage rate. In this work, an external beam RBS system established in Fudan University was used to measure helium in ICF target. The accuracy of the system was verified firstly by measuring a helium contained sample, and comparing the result of it with RBS, Elastic Recoil Detection Analysis (ERD). The result of external beam RBS agrees well with the other two methods. Whereafter, a hollow glass microsphere (HGM) pellet was filled with helium and studied with this external RBS system. The obtained RBS spectrum was analyzed with SIMNRA and the helium amount and the half life of gas reservation of the pellet was calculated. The half life of gas reservation of the pellet studied in the work was calculated to be 45 minutes.

The transparent conductive oxide (TCO) SnO2:Ta is developed as a selectively solar-transmitting coating for concentrated solar power (CSP) absorbers. Upon covering with an antireflective layer, a calculated absorptivity of 95 % and an emissivity of 30 % are achieved for the model configuration of SnO2:Ta on top of a perfect black body (BB). High-temperature stability of the developed TCO up to 1073 K is shown in situ by spectroscopic ellipsometry and Rutherford backscattering spectrometry. The universality of the concept is demonstrated by transforming silicon and glassy carbon from non-selective into solar-selective absorbers by depositing the TCO on top of them. Finally, the energy conversion efficiencies of SnO2:Ta on top of a BB and an ideal non-selective BB absorber are extensively compared as a function of solar concentration factor C and absorber temperature TH. Equal CSP efficiencies can be achieved by the TCO on BB configuration with approximately 50 % lower solar concentration. This improvement could be used to reduce the number of mirrors in a solar plant, and thus, the levelized costs of electricity for CSP technology.

In this work, the waveguide formation mechanism and related optical properties in strontium titanate crystal irradiated with 357 MeV Ni-ion at a fluence of 5 × 1013 cm−2 have been studied. The electronic energy loss along the swift heavy ion penetration path could produce lattice damage based on the inelastic thermal spike model, and therefore modify the refractive index distribution and further induce a waveguide formation. Irradiation damage behavior in the near-surface region has been analyzed by Rutherford backscattering spectrometry in a channeling direction. Optical properties of the prepared strontium titanate waveguide at visible and near-infrared wavelengths, including the guided mode, near-field intensity distribution and transmission loss, have been characterized by prism and end-face coupling measurements. Due to the relatively deep penetration of the swift heavy ions, the formed waveguide structure could effectively support multi-mode and single-mode transmissions in the visible and near-infrared regions, respectively. Utilizing the measured effective refractive indices of guided modes, the refractive index profile of the irradiation region has been reconstructed by the inverse Wentzel-Kramers-Brillouin method, further proving that the electronic energy loss induced by swift heavy ion irradiation plays a dominant role in the formation of strontium titanate waveguides.

The electrochemistry of ruthenium (Ru) etching in acidic solution containing cerium (IV) (Ce4+) has been investigated. Voltammograms were measured to determine the onset potentials of metal stripping and cathodic reduction of the oxidizing agent. Etch rates of blanket thin films of chemical vapour deposited Ru were measured using Rutherford backscattering spectrometry. Sheet resistance measurements of a thickness range of wet-chemically etched and as-deposited Ru thin films are compared. X-ray photoelectron spectroscopy was used to characterize post-etching residues. Using atomic force microscopy, the surface morphology of Ru after etching and removal of residues by rinsing with water or acid and ultrasonic agitation was studied. Compatibility of low-k dielectric material with the etchant has been assessed using Fourier transform infrared spectroscopy. UV–vis absorption spectroscopy was used to study the stability and absorption features of various Ce4+ compounds in sulphuric and methane sulphonic acid. Additionally, mixtures containing Ce4+ and Ce3+ were analyzed. In situ measurements during Ru etching show the conversion of the oxidizing agent to Ce3+.

Silicon (Si) has been the most widely used semiconductor for decades, playing an important role in the field of electronics, energy conversion and energy storage. Because of their unique morphological energy band characteristics, Si nanostructures exhibit superior performance in many applications in comparison with their bulk counterparts. In this study, the effects of thermal annealing on elemental composition and morphological properties of palladium metal thin films grown on c-Si substrates were investigated. Palladium (Pd) thin films of different thicknesses were deposited on Si (1 0 0) with and without native oxide layers by electron beam evaporation and annealed in vacuum at 600 °C for two hours. Scanning electron microscopy (SEM) studies have shown that the surface morphology showed an effective dewetting in individual droplets and islands which further coalesce into bigger islands. Rutherford backscattering spectrometry (RBS) and electrical measurements analyses revealed the diffusion of the Si substrate into the Pd layer during annealing. This contribution will discuss the effects of the metal layer thickness as well as the native oxide on the metal thin films.

ZnSxTe1-x thin films were prepared by sulfur implantation into ZnTe grown by molecular beam epitaxy and subsequent pulsed laser melting. The chemical composition and layer thickness of the ZnSxTe1-x layer have been analyzed based on Rutherford backscattering spectrometry. Raman and photoluminescence spectroscopies were employed to reveal the optical properties of the ZnSxTe1-x layer. Raman spectra exhibit a redshift of the longitudinal optical photon modes with increasing sulfur concentration. The room temperature photoluminescence measurement indicates the appearance of the sulfur induced energy state in the bandgap.

This work is meant to respond the challenge of manufacturing osmium targets for nuclear astrophysics experiments using the activation method with alpha particles. In this context, PLD (Pulsed Laser Deposition) was used to prepare osmium targets without specks or wrinkles and with a very well defined and constant thickness. Characterization techniques as RBS (Rutherford Backscattering Spectrometry), AFM (Atomic Force Microscopy), SEM/EDX (Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy) and XRD (X-ray Diffraction) were used to determine accurately the features of the obtained targets. The obtained results reveal that the PLD technique is suitable for the preparation of high quality thin/thick osmium targets.