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One of the new developing technologies for increasing hardness, wear resistance and lifetime of cutting tools are the Ti-Si-C-N nanocomposite coatings deposited by a LARC® method. To investigate the effect of the various coating deposition parameters on the coating properties, the Ti-Si-C-N layers were deposited on Ni2Cu backings. The nondestructive Ion Beam Analysis (IBA) was used for determination of elemental composition depth profiles of the prepared layers, so that samples can be further mechanically tested. By application of Rutherford Backscattering Spectrometry (RBS), Proton Induced X-ray Emission (PIXE), Elastic Recoil Detection Analysis (ERDA) and Nuclear Reaction Analysis (NRA) the concentration of Ti, Si, C, N and H was determined. The depth profiles of the individual elements in the surface area and in the layer interface with the backing material were also determined.One of the new developing technologies for increasing hardness, wear resistance and lifetime of cutting tools are the Ti-Si-C-N nanocomposite coatings deposited by a LARC® method. To investigate the effect of the various coating deposition parameters on the coating properties, the Ti-Si-C-N layers were deposited on Ni2Cu backings. The nondestructive Ion Beam Analysis (IBA) was used for determination of elemental composition depth profiles of the prepared layers, so that samples can be further mechanically tested. By application of Rutherford Backscattering Spectrometry (RBS), Proton Induced X-ray Emission (PIXE), Elastic Recoil Detection Analysis (ERDA) and Nuclear Reaction Analysis (NRA) the concentration of Ti, Si, C, N and H was determined. The depth profiles of the individual elements in the surface area and in the layer interface with the backing material were also determined.

We study the reduction of graphene oxide (GO) sheets, synthesized by modified Hummer’s method, using medium energy ion beams (500 keVAr+ or 500 keVN+). Resonant Rutherford backscattering spectrometry technique has been employed to quantify the oxygen reduction upon irradiation. Ion irradiation process results exponential reduction with the increase of fluence. The C/O ratio of Ar+ ion irradiated samples is larger than the N+ irradiated sample, indicating that Ar+ ion beam can be effectively used to reduce GO. The grazing incident X-ray diffraction analysis also reveals that the RGO content is enhanced in Ar+ ion irradiated sample in comparison with N+ irradiated sample.

Selective deoxygenation of graphene oxide has been conducted with regard with the design and fabrication of graphene based devices. The ion beam lithography is considered to be a powerful method for patterning onto graphene oxide foil. A helium beam has been used for both direct patterning onto graphene oxide foil and simultaneous online characterisation of its structural and compositional changes. Scanning electron microscopy, energy dispersive spectroscopy and Rutherford backscattering spectrometry analyses have been accurately employed to reveal and monitor the deoxygenation of the graphene oxide foil demonstrating the reliability of the direct patterning using the ion beam lithography technique.

We report a systematic investigation on photoluminescence (PL) behaviour of Au/ZnO/Au hybrid nanostructure. The ZnO (150 nm), and Au (10 nm)/ZnO (150 nm)/Au(10 nm) were deposited on quartz substrate by pulsed laser deposition (PLD) technique. The thickness of ZnO and Au films has been estimated from Rutherford backscattering spectrometry measurements. The X-ray diffraction analysis is performed on the samples to study the crystalline quality of the hybrid nanostructure. The PL behaviour of Au/ZnO/Au hybrid nanostructure shows an enhanced UV emission and completely suppressed visible emission in pristine ZnO film. The enhanced UV emission and suppression of visible emission might be due to the combined effect of exciton-plasmon coupling and the passivation of surface traps.

Resonant Rutherford backscattering spectrometry (RRBS) technique can be used for analysis and quantification of carbon in few layer graphene and graphene oxide films. The carbon concentration estimated using RRBS measurements satisfactorily agreed with the theoretically reported value. Our experimental studies evidenced that RRBS technique can be used for the analysis of carbon in graphene based material, particularly, RRBS with glancing incident angle with its high sensitivity can be effectively used for thickness and estimation of carbon concentration.

Room temperature deposition of molybdenum-copper thin films have been performed by ion beam sputtering and characterized by x-ray diffraction, x-ray reflectivity, & Rutherford backscattering spectrometry studies. Electrical resistivity measurements were performed up to milli-Kelvin temperatures and residual resistivity ratio values have been calculated to figure out a correlation with copper thickness.Room temperature deposition of molybdenum-copper thin films have been performed by ion beam sputtering and characterized by x-ray diffraction, x-ray reflectivity, & Rutherford backscattering spectrometry studies. Electrical resistivity measurements were performed up to milli-Kelvin temperatures and residual resistivity ratio values have been calculated to figure out a correlation with copper thickness.

We investigate the interface mixing across Pd0.60 Ni0.40 (∼20 nm)/SiO2 interface on irradiation by 100 MeV Au ions at a fluence 1 × 1014 ions/cm2. The samples were characterized using Rutherford backscattering spectrometry (RBS) and x-ray photoelectron spectroscopy (XPS). From RBS results, a weak but significant intermixing is observed at the interface. The XPS spectra suggest that the irradiation first homogenizes the alloy film and then causes an interdiffusion of Pd and Ni atoms in SiO2.

Hafnium oxide (HfO2) is the potentially useful dielectric material in both; electronics to replace the conventional SiO2 as gate dielectric and in Optics as anti-reflection coating material. In this present work we have synthesized polycrystalline HfO2 thin films by RF magnetron sputtering deposition technique with varying target to substrate distance. The deposited films were characterized by X-ray Diffraction, Rutherford Backscattering Spectrometry (RBS) and transmission and Reflection (T&R) measurements to study the growth behavior, microstructure and optical properties. XRD measurement shows that the samples having mixed phase of monoclinic, cubic and tetragonal crystal structure. RBS measurements suggest the formation of Inter Layer (IL) in between Substrate and film

The purpose of this study is the study of the physical parameters of a multilayer dichroic produced by PVD Magnetron Sputtering. The multilayers were designed by using a dedicated software and subsequently characterized by Rutherford Backscattering Spectrometry (RBS) in order to determine both the stoichiometry of the deposited oxides (SiO2 and TiO2) and the homogeneity of the film surface. RBS technique allowed to verify the variation of the deposited multilayer after annealing. AFM analysis was used to determine the roughness and thickness of the deposited layers, while some key parameters for optical behavior were obtained with a spectrophotometric analysis. These specific multilayers have been used in optical applications and particularly in the separation of the spectrum of the solar radiation systems for concentration photovoltaics (CPV).

Transpiration experiments were performed on candidate solid oxide fuel cell (SOFC) materials at 800°C in humid air. Vapors produced via gas-solid interactions were collected on the surface of wafers located downstream from the reaction. Wafers were analyzed using Rutherford backscattering spectrometry (RBS) to determine the amount of material volatized over the duration of an experiment.

The migration of radionuclides (RN) in the environment is a topic of general interest, for its implications on public health, and it is an issue for the long-term safety studies of deep geological repositories (DGR) for high-level radioactive waste. The role played by colloids on RN migration is also of great concern. Diffusion and sorption are fundamental mechanisms controlling RN migration in rocks and many experimental approaches are applied to determine transport parameters for low sorbing RN in homogeneous rocks. However, it is difficult to obtain relevant data for high sorbing RN or colloids, for which diffusion lengths are extremely short, or within heterogeneous rocks, where transport might be different in different minerals. The ion beam techniques Rutherford Backscattering Spectrometry (RBS) and micro-Particle Induced X-Ray Emission (μPIXE), rarely applied in the field, were selected for their micro-analytical potential to study RN diffusion and surface retention within heterogeneous rocks. Main achievements obtained during last 12 years are highlighted.

PbTe thin film were synthesized using thermal evaporation and irradiated by 100 MeV Ag ions at different fluences ranging from 3×1013 and 1×1014 ions/cm2. Pristine films annealed under Ar atm at 250 °C for 1 hr. X-ray Diffraction (XRD) of pristine and irradiated films reveals the improvement of PbTe phase with increasing fluence. The thickness of the film is decreased from 195 nm to 150 nm after ion irradiation as indicated by Rutherford backscattering spectrometry (RBS) analysis due to the sputtering. Resistivity measurement using four probe techniques of these films shows the conductivity enhancement with ion fluence. The conductivity is found to be ∼ 6 fold at fluence 3×1013 ions/cm2 whereas it decreases to 3 fold after annealing in comparison to pristine sample. On further increasing the fluence from 3×1013 ions/cm2, the properties of the film begin to deteriorate. SHI induced modification may be explained on the basis of oxygen desorption and change in stochiometry of film during irradiation.

We present experimental results on shallow junction formation in germanium by phosphorus ion implantation and standard rapid thermal processing. An attempt is made to improve phosphorus activation by implanting phosphorus at high and low temperature. The focus is on studying the germanium damage and phosphorus activation as a function of implant temperature. Rutherford backscattering spectrometry with channelling and Hall Effect measurements are employed for characterisation of germanium damage and phosphorus activation, respectively. High and low temperature implants were found to be better compared to room temperature implant.

Particle‐Induced X‐ray Emission (PIXE) analysis was employed to characterize hydroxypropyl methylcellulose (HPMC) C32H60O19 polymer film via areal density measurement on silicon‐based substrates utilizing the differential PIXE concept, and compared with Rutherford backscattering spectrometry (RBS) results. It is demonstrated in this paper that PIXE and RBS measurements both yield comparable results for areal densities ranging from 1018 atom/cm2 to several 1019 atom/cm2. A collection of techniques including PIXE, RBS, tapping mode atomic force microscopy (TMAFM), and contact angle analysis were used to compute surface free energy, analyze surface topography and roughness parameters, determine surface composition and areal density, and to predict the water affinity and condensation behaviors of silicates and other compounds used for high impact resistance vision ware coatings. The visor surface under study is slightly hydrophilic, with root mean square of surface roughness on the order of one nm, and surfac...

Investigations into the effects of high‐energy ion bombardment of ultrananocrystalline diamond (UNCD) thin films was performed using 3 and 6 MeV protons and 24 MeV F4+, with the fluence of 2.1×1017 ions/cm2, 2.9×1017 ions/cm2, and 6.7×1015 ions/cm2 respectively. Objective of the research is to investigate the effect of structural damage on the physical properties of the material and compare it with the structure of unirradiated and N doped UNCD. Pre‐ and post‐irradiated samples were analyzed by ion beam analysis (IBA) measurements, Raman spectroscopy, atomic force microscopy (AFM) and scanning electron microscopy (SEM). IBA measurements including Rutherford backscattering spectrometry (RBS), non‐Rutherford backscattering spectrometry (NRBS) and elastic recoil detection analysis (ERDA) were used to determine elemental concentration of pre‐ and post‐irradiated samples. Visible Raman spectra corresponding to samples irradiated at 3 and 6 MeV protons did not show much variation. For 24 MeV F4+ irradiated samp...

The experimental set-up at the ion beam facility in Jena allows the performance of Rutherford backscattering spectrometry (RBS) in channeling configuration at any temperature between 15 K and room temperature without changing the environment or the temperature of the sample. Doing RBS channeling studies at 15 K increases the sensitivity to defects, because the influence of lattice vibrations is reduced. Thus, the very early processes of ion induced damage formation can be studied and the cross section of damage formation per ion in virgin material, P, can be determined. At 15 K ion-beam induced damage formation itself can be investigated, because the occurrence of thermal effects can be widely excluded. In AlAs, GaN, and ZnO the cross section P measured at 15 K can be used to estimate the displacement energy for the heavier component, which is in reasonable agreement with other experiments or theoretical calculations. For a given ion species (here Ar ions) the measured cross section P exhibits a quadratic dependence P{proportional_to}P{sub SRIM}{sup 2} with P{sub SRIM} being the value calculated with SRIM using established displacement energies from other sources. From these results the displacement energy of AlN can be estimated to about 40 eV. Applying the computermore » code DICADA to calculate the depth distribution of displaced lattice atoms from the channeling spectra, indirect information about the type of defects produced during ion implantation at 15 K can be obtained. In some materials like GaN or ZnO the results indicate the formation of extended defects most probably dislocation loops and thus suggest an athermal mobility of defect at 15 K.« less

The efficiency of thermoelectric devices and materials is limited by the properties of n‐ and p‐type (semi)conductors. Effective thermoelectric materials have a low thermal conductivity and a high electrical conductivity. The performance of thermoelectric materials and devices is shown by a dimensionless figure of merit, The performance of thermoelectric materials and devices is shown by a dimensionless figure of merit, ZT = S2σT/K, where S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature and K is the thermal conductivity. ZT can be increased by both increasing S and σ, or decreasing K. In this study we have prepared a thermoelectric generator from 100 alternating layers of SiO2/SiO2+Au superlattice films using ion beam assisted deposition (IBAD). In order to determine the stoichiometry of SiO2 and Au in the grown multilayer films, Rutherford Backscattering Spectrometry (RBS) was used. The 5 MeV Si ions bombardment was performed using the CIM Pelletron ion beam accelerator to make nanodots and/or nanoclusters in the multi‐layer superlattice thin films to decrease the cross plane thermal conductivity, increase the cross plane Seebeck coefficient and increase the cross plane electrical conductivity.

The water affinity of Si-based surfaces is quantified by contact angle measurement and surface free energy to explain hydrophobic or hydrophilic behavior of silicone, silicates, and silicon surfaces. Surface defects such as dangling bonds, surface free energy including Lewis acid-base and Lifshitz-van der Waals components are discussed. Water nucleation and condensation is further explained by surface topography. Tapping mode atomic force microscopy (TMAFM) provides statistical analysis of the topography of these Si-based surfaces. The correlation of the above two characteristics describes the behavior of water condensation at Si-based surfaces. Surface root mean square roughness increasing from several A to several nm is found to provide nucleation sites that expedite water condensation visibly for silica and silicone. Hydrophilic surfaces have a condensation pattern that forms puddles of water while hydrophobic surfaces form water beads. Polymer adsorption on these surfaces alters the water affinity as well as the surface topography, and therefore controls condensation on Si-based surfaces including silicone intraocular lens (IOL). The polymer film is characterized by Rutherford backscattering spectrometry (RBS) in conjunction with 4.265 MeV 12 C(α, α) 12 C, 3.045 MeV 16 O(α, α) 16 O nuclear resonance scattering (NRS), and 2.8 MeV elastic recoil detection (ERD) of hydrogen for high resolution composition and areal density measurements. The areal density of hydroxypropyl methylcellulose (HPMC) film ranges from 10 18 atom/cm 2 to 10 19 atom/cm 2 gives the silica or silicone surface a roughness of several A and a wavelength of 0.16 ± 0.02 μm, and prevents fogging by forming a complete wetting layer during water condensation.

Silica‐based glasses containing silver nanoparticles have been shown to be promising materials in photonic applications. Various silica‐based glasses were implanted with 1.7 MeV Ag+ ions with fluences of 1×1016 cm−2 and annealed at 600 °C for 5 hours. The concentration depth profiles were characterised using Rutherford Backscattering Spectrometry (RBS) and X‐ray Photoelectron Spectroscopy (XPS). The measured concentration depth profiles of the implanted Ag atoms were compared with the theoretically predicted implantation profiles simulated by SRIM‐2008. The optical properties of the prepared nanostructures were examined by UV‐VIS spectroscopy. It was found that the composition and structure of the glass has an influence on the penetration of the implanted ions during the implantation and post‐implantation annealing, on the oxidation state of silver present in the glass matrix and on the resulting optical properties.

Growth of Ag film on Br‐ and H‐passivated Si(111) surfaces was examined by Rutherford backscattering spectrometry (RBS), scanning electron microscopy (SEM) and photoemission electron microscopy (PEEM) techniques. The phenomenon of thermal grooving was observed after annealing at higher temperatures. Hierarchical desorption of Ag from the grain boundaries produce a fractal structure of Ag‐depleted regions. Hierarchical desorption may be used for nanopatterning of the layer.

Determination of the elemental composition is important to correlate the properties of nitrogen incorporated Ultrananocrystalline Diamond (UNCD) thin films with their growth conditions. Films were deposited by CVD deposition technology and nitrogen incorporation was introduced by diluting the growth Ar/CH4 plasma with N2 gas. Deposition of UNCD thin films was carried out on tungsten (∼15 nm) coated Si substrates with varying concentrations of N2 diluted to the growth plasma. Scanning electron microscopy (SEM) and Raman spectroscopy (RS) were used to confirm the characteristic morphology of the UNCD film and its dominant sp3 bonding respectively. The deposited films were smooth on the submicron scale with the RMS roughness value of 2.9–5.1 nm. Reflectometry spectroscopy analysis (RES) technique was used to measure the films thicknesses. To obtain the elemental composition of the UNCD thin films, Rutherford Backscattering Spectrometry (RBS), Non‐Rutherford Backscattering Spectrometry (NRBS), Elastic Recoil Detection Analysis (ERDA) and Nuclear Reaction Analysis (NRA) were performed. Deposited UNCD films contained less than 5 at.% of H while N content incorporated in the films was estimated to be lower than 1 at.%. The intermixing region between the substrate and the film was found to be negligible. Moreover, amorphous phase as determined by Raman analysis was found to be increasing for the sample deposited with N2.

Thin, hydrogenated aluminum hydride films were deposited on silicon substrates using unbalanced magnetron (UBM) sputtering of a high purity aluminum target under electrically grounded conditions. Argon was used as sputtering gas and hydrogenation was carried out by diluting the growth plasma with hydrogen. The effect of hydrogen partial pressure on the final concentration of trapped elements including hydrogen has been studied using ion beam analysis (IBA) techniques. Moreover, in‐situ thermal stability of trapped hydrogen in the film was carried out using Rutherford Backscattering Spectrometry (RBS), Non‐Rutherford Backscattering Spectrometry (NRBS) and Elastic Recoil Detection Analysis (ERDA). Microstructure of the film was investigated by SEM analysis. Hydrogen content in the thin films was found decreasing as the films were heated above 110 °C in vacuum.

The main characteristics of the ion beam facility based on a 3.75 MeV Van de Graaff accelerator at the University of Chile are described at this work. Current activities are mainly focused on the application of the Ion Beam Analysis techniques for environmental, archaeological, and material science analysis. For instance, Rutherford Backscattering Spectrometry (RBS) is applied to measure thin gold film thickness which are used to determine their resistivity and other electrical properties. At this laboratory the Proton Induced X‐Ray Emission (PIXE) and Proton Elastic Scattering Analysis (PESA) methodologies are extensively used for trace element analysis of urban aerosols (Santiago, Ciudad de Mexico). A similar study is being carried out at the Antarctica Peninsula. Characterization studies on obsidian and vitreous dacite samples using PIXE has been also perform allowing to match some of these artifacts with geological source sites in Chile.Basic physics research is being carried out by measuring low‐ener...

Single‐phase rock‐salt MgZnO films with high Zn content were successfully fabricated on the templates of MgO (111)/α‐sapphire (0001) by radio‐frequency plasma assisted molecular beam epitaxy. The influence of growth temperature on epitaxy of MgZnO alloy films was investigated by the combined studies of crystal structures, compositions, and optical properties. It is found that the incorporation of Zn atoms into the rock‐salt MgZnO films is greatly enhanced at low temperature, confirmed by in‐situ reflection high‐energy electron diffraction observations and ex‐situ X‐ray diffraction characterization. Zn fraction in the single‐phase rock‐salt Mg0.53Zn0.47O film was determined by Rutherford backscattering spectrometry. Optical properties of the films were investigated by transmittance spectroscopy and reflectance spectroscopy, both of which demonstrate the solar‐blind band gap and its dependence on Zn content.

Thin Ti‐rich diffusion barrier layers were found to be formed at the interface between Cu(Ti) films and SiO2/Si substrates after annealing at elevated temperatures. This technique was called “self‐formation of the diffusion barrier,” which is attractive for fabrication of ultra‐large scale integrated (ULSI) interconnects. In the present study, we investigated the applicability of this technique to Cu(Ti) alloy films deposited on low dielectric constant (Low‐k) materials (SiOxCy). In addition, SiCO and SiCN were also used as dielectric layers, which are potential dielectric layers for future ULSI‐Si devices. The microstructures were analyzed by transmission electron microscopy (TEM), Rutherford backscattering spectrometry (RBS) and secondary ion mass spectrometry (SIMS), and correlated with the electrical properties of the Cu(Ti) films. The resistivity of the Cu(1 at.%Ti)/dielectric‐layer samples was reduced to about 2.5 μΩcm after annealing in Ar at 400° C for 2 h. It was concluded that the Ti‐rich interf...