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Abstract: Periodic layers of various elements, such as Au/SiO2/Au, V2O3/SiO2 and VO/SiO2 were deposited and then bombarded by MeV ions to form nanolayers of nanocrystals. We have used the energy deposited due to the electronic excitation by post-irradiation to induce the nucleation of nanoclusters of metal ions in silica. The results were compared with post-annealing. The process of ion beam assisted nucleation of nanocluster was used to produce nanocrystals of Au in silica host. A formal treatment of ion beam induced diffusion is introduced with an appropriate diffusion coefficient. [Copyright &y& Elsevier]

Abstract: Proton induced X-ray emission (PIXE) is famously effective for revealing trace elements in biological tissue in which the majority elements (H, C, N and O) have low Z. When the majority elements in a compound have high atomic numbers, the yield of K and L X-rays following proton bombardment often mask those of lighter trace elements, or dominate the counting rate to such an extent that the time required to detect a small signal with statistical significance becomes prohibitively long. We have confronted these difficulties with a PIXE analysis of YAG crystals and ceramics with neodymium doping up to nine atomic percent. The K X-rays of aluminum (1.74keV) and yttrium (15keV) dominate the PIXE spectrum. The L X-rays from neodymium group near 5keV provide determination of the neodymium content of Nd:YAG to 1:1000. Clear signals of traces of zinc, nickel and copper were recovered from the spectra of some of the samples by persistent experiments at low counting rates that avoided pile up of the signals from the majority elements. An appropriate polyethylene filter was used to prevent scattered protons from striking the detector and its supporting structure. Double proton beam collimation prevented spurious PIXE from the chamber walls, beam stop and the primary collimator. No material was near the sample except a polyethylene film strip that supported the sample. [Copyright &y& Elsevier]

Abstract: Using focused ion beam (FIB) milling, SOI wafer with heavily doped p-type Si (100) membrane was fabricated into stencil mask used for patterned heavy ion implantation. Because of the high electrical conductivity, high thermal conductivity and crystalline orientation of Si membrane, the mask can greatly decrease the thermal spike damage and the ionization discharge damage induced by heavy ion irradiation, keeping dimensional stability. Effective patterned implantation with ion energy of 60keV can be achieved under the fluence below 2×1017 ions/cm2. The patterned metallic implanted c-SiO2 shows enhanced surface plasmon resonance and pronounced nonlinear optical property. [Copyright &y& Elsevier]

Abstract: The defects and disorder in the thin films caused by MeV ions bombardment and the grain boundaries of these nanoscale clusters increase phonon scattering and increase the chance of an inelastic interaction and phonon annihilation. We prepared the thermoelectric generator devices from 100 alternating layers of SiO2/SiO2 +Cu multi-nano layered superlattice films at the total thickness of 382nm and 50 alternating layers of SiO2/SiO2 +Au multi-nano layered superlattice films at the total thickness of 147nm using the physical vapor deposition (PVD). Rutherford Backscattering Spectrometry (RBS) and RUMP simulation have been used to determine the stoichiometry of the elements of SiO2, Cu and Au in the multilayer films and the thickness of the grown multi-layer films. The 5MeV Si ions bombardments have been performed using the AAMU-Center for Irradiation of Materials (CIM) Pelletron ion beam accelerator to make quantum (nano) dots and/or quantum (quantum) clusters in the multilayered superlattice thin films to decrease the cross plane thermal conductivity, increase the cross plane Seebeck coefficient and cross plane electrical conductivity. To characterize the thermoelectric generator devices before and after Si ion bombardments we have measured Seebeck coefficient, cross-plane electrical conductivity, and thermal conductivity in the cross-plane geometry for different fluences. [Copyright &y& Elsevier]

Abstract: Effective thermoelectric materials and devices have a low thermal conductivity and a high electrical conductivity. The performance of the thermoelectric materials and devices is shown by a dimensionless figure of merit, ZT. The purpose of this study is to improve the figure of merit of the single layer of Er0.1Fe1.9SbGe0.4 thin film used as thermoelectric generators. We have deposited the monolayer of Er0.1Fe1.9SbGe0.4 thin film on silicon and silica substrates with thickness of 302nm using ion beam assisted deposition (IBAD). Rutherford backscattering spectrometry (RBS) was used to determine the total film thickness and stoichiometry. The MeV Si ion bombardments were performed on single layer of Er0.1Fe1.9SbGe0.4 thin films at five different fluences between 5×1013−5×1015 ions/cm2.The defect and disorder in the lattice caused by ion beam modification and the grain boundaries of these nanoscale clusters increase phonon scattering and increase the chance of annihilation of the phonon. The increase of the electron density of states in the miniband of the quantum dot structure formed by bombardment also increases the Seebeck coefficient and the electrical conductivity. We measured the thermoelectric efficiency of the fabricated device by measuring the cross plane thermal conductivity by the 3rd harmonic (3ω) method, the cross plane Seebeck coefficient, and the electrical conductivity using the Van Der Pauw method before and after the MeV ion bombardments. [Copyright &y& Elsevier]

Abstract: We have grown three different monolayer Co0.1Sb x Ge y (x =2,4,11 and y =15,7,15) thin films on silica substrates with varying thickness between 100 and 200nm using electron beam deposition. The high-energy (in the order of 5MeV) Si ion bombardments have been performed on samples with varying fluencies of 1×1012, 1×1013, 1×1014 and 1×1015 ions/cm2. The thermopower, electrical and thermal conductivity measurements were carried out before and after the bombardment on samples to calculate the figure of merit, ZT. The Si ions bombardment caused changes on the thermoelectric properties of films. The fluence and temperature dependence of cross plane thermoelectric parameters were also reported. Rutherford backscattering spectrometry (RBS) was used to analyze the elemental composition of the deposited materials and to determine the layer thickness of each film. [Copyright &y& Elsevier]

Abstract: SiO2 +Au thin films were prepared on SiO2 substrates using ion beam assisted deposition (IBAD). The film was annealed at different temperatures. After each annealing, the optical absorption spectrum was taken to monitor the gold nanocluster formation in the thin film. By using Doyle’s formula, the size of the nanoclusters was determined and plotted as a function of the annealing temperature. Separately, other identical films were bombarded with ions of different energies and different fluence to monitor the nanoclusters forming during the bombardments. We have compared the effect of electronic energy deposition of the energetic ions with the effect of annealing at various temperatures. [Copyright &y& Elsevier]

Abstract: The three single layer Ce3Sb10 thin films were grown on silicon dioxide and quartz (suprasil) substrates with thicknesses of 297, 269 and 70nm using ion beam assisted deposition (IBAD) technique. The high-energy cross plane Si ion bombardments with constant energy of 5MeV have been performed with varying fluence from 1×1012, 1×1013, 1×1014, 1×1015 ions/cm2. The Si ions bombardment modified the thermoelectric properties of films as expected. The fluence and temperature dependence of cross plane thermoelectric parameters that are Seebeck coefficient, electrical and thermal conductivities were determined to evaluate the dimensionless figure of merit, ZT. Rutherford backscattering spectrometry (RBS) enabled us to determine the elemental composition of the deposited materials and layer thickness of each film. [Copyright &y& Elsevier]

Abstract: We made n-type nano-scale thin film thermoelectric (TE) devices that consist of multiple periodic layers of Si1− x Ge x /Si. The period is about 10nm. The structure was modified by 5MeV Si ion bombardment that formed a nano-scale cluster structure. In addition to the effect of confinement of the phonon transmission, formation of nanoclusters by the ionization energy of incident MeV Si ions further increases the scattering of phonons, increasing the chance of inelastic interaction of phonons, resulting in more annihilation of phonons. This limits phonon mean free path. Phonons are absorbed and dissipated along the layers rather than in the direction perpendicular to the layer interfaces, therefore cross plane thermal conductivity is reduced. The increase of the density of electronic states due to the formation of nanocluster minibands increases the cross plane Seebeck coefficient and increases the cross plane electric conductivity of the film. Eventually, the thermoelectric figure of merit of the TE film increases. [Copyright &y& Elsevier]

Abstract: We prepared 50 periodic nano-layers of electro-cooling system consisting of SiO2/Au x SiO2(1−x) super lattice with Au layer deposited on both sides as metal contacts. The deposited multilayer films have a periodic structure consisting of alternating layers where each layer is 10nm thick. The purpose of this research is to tailor the figure of merit of layered structures used as thermoelectric generators. The super lattices were then bombarded by 5MeV Si ions at three different fluences to form nano-cluster structure. Rutherford backscattering spectrometry (RBS) was used to monitor the film thickness and stoichiometry before and after MeV bombardment. We measured the thermoelectric efficiency of the fabricated device before and after 5MeV bombardment measuring the cross plane thermal conductivity by third harmonic method, measuring cross plane Seebeck coefficient, and measuring electric conductivity using Van der Pauw method. As predicted the electronic energy deposited due to ionization by MeV Si beam in its track produces nano-scale structures which disrupt and confine phonon transmission therefore reducing thermal conductivity, increasing electron density of state so as to increase Seebeck coefficient, and electric conductivity, thus increasing figure of merit. [Copyright &y& Elsevier]

Abstract: Chemical surface characterization of C+H hybrid ion implanted UHMWPE samples were carried out using DSC (differential scanning calorimeter) and TGA (thermal gravimetric analysis) techniques. Samples were implanted with a fluence of 1017 ion/cm2 and an extraction voltage of 30kV. The study of TGA and DSC curves showed that: (1) Polymeric decomposition temperature increased, (2) T m, ΔC p and ΔH m values changed while ΔC p and ΔH m increased. T g value could not be measured, because of some experimental limitations. However, the increase in ΔH m values showed that T g values increased, (3) the branch density which indicated the increase in number of cross-link (M c) decreased in ion implanted samples and (4) increase in ΔH m values indicated increase in crystallinity of implanted surface of UHMWPE samples. [Copyright &y& Elsevier]

Abstract: Most of total hip joints are composed of ultra-high molecular weight polyethylene (UHMWPE ). However, as ultra-high molecular weight polyethylene is too stable in a body, wear debris may accumulate and cause biological response such as bone absorption and loosening of prosthesis. In this study, ultra-high molecular weight polyethylene samples were Ag and Ag+N hybrid ion implanted by using MEVVA ion implantation technique to improve its surface properties. Samples were implanted with a fluence of 1017 ion/cm2 and extraction voltage of 30kV. Implanted and unimplanted samples were investigated by thermo-gravimetry analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), optical microscopy (OM) and contact Angle measurement. Thermal characterization results showed that the ion bombardment induced an increase in the % crystallinity, onset and termination degradation temperatures of UHMWPE. [Copyright &y& Elsevier]

Abstract: We have introduced various nanopowders in the precursor of glassy polymeric carbon (GPC) and studied the electrical properties as well as the chemical structure. In general the GPC ware produced at Alabama A&M University (AAMU) is used for making crucibles, heat exchangers and for prosthetic devices because of its biocompatibility and inertness. GPC ware at AAMU is synthesized from a phenolic resin solution from Georgia Pacific in a pyrolyzer system at temperatures between 100°C and 2800°C. The heat treatment includes several stages: gelling, curing, postcuring, precarbonization and carbonization. The fabrication of GPC is complicated because of the high production rate of gaseous products in critical temperature ranges where out-diffusion is relatively slow. Special care should be taken in temperature programming to avoid kilning faults and misshapen or porous GPC end results [H. Maleki, L.R. Holland, G.M. Jenkins, et al., Carbon 35 (1997) 227]. In this work we have introduced 1wt% of SiC, carbon nanotubes (CNT) and Al2O3 to the precursor, pyrolyzed composites to 1000°C and studied the effect of 1MeV and 3MeV proton bombardment on the final products. [Copyright &y& Elsevier]

Abstract: Inclusion of metal ions in photorefractive materials followed by thermal annealing leads to an increase in optical absorption. The glow discharge as well as thermal annealing have been used to change the optical properties of suprasil. We used the effects of the low-energy ions to induce the nucleation of nanocrystals on and near the surface of a silica nano-layer containing low concentrations of Au, produced by using the co-deposition of Au and silica thin film on a suprasil substrate. Au-nanoclusters were formed both by thermal annealing and glow discharge, then observed and studied by Rutherford backscattering spectrometry (RBS) and by optical absorption photospectrometry. [Copyright &y& Elsevier]

Abstract: Epitaxial thin films of La2NiMnO6, a ferromagnetic semiconductor, have been fabricated on different substrates by pulsed laser deposition (PLD) [H. Guo, J. Burgess, S. Street, A. Gupta, T.G. Calvarese, M.A. Subramanian, Appl. Phys. Lett. 89 (2006) 0225509]. X-ray diffraction and Raman scattering observations show that the films are single crystalline and have an orthorhombic structure. Rutherford backscattering spectrometry (RBS) measurements were done on four different samples using 2.1MeV He+ ions. We used RUMP simulation on the RBS data to extract information about the thickness and stoichiometry of the layers. In this paper, we are discussing the differences of the various films investigated. [Copyright &y& Elsevier]

Abstract: We made 50 periodic nano-layers of Bi x Te3/Sb2Te3 superlattice films with Au layers deposited on both sides as metal contacts. Each alternating layer is 5nm thick. The performance of the thermoelectric materials and devices is shown by a dimensionless figure of merit, ZT. The purpose of this study is to tailor the figure of merit of layered structures used as thermoelectric generators. The superlattices were bombarded by 5MeV Si ions at seven different fluences to form nano-cluster structures. Rutherford backscattering spectrometry (RBS) was used to determine the film thickness and stoichiometry. To get the figure of merit before and after MeV bombardments, we measured the cross plane thermal conductivity by 3rd harmonic method, cross plane Seebeck coefficient and electrical conductivity using Van der Pauw method. The electronic energy deposited due to ionization by the MeV Si beam in its track produces nano-scale structures. This disrupts and confines phonon transmission thereby reducing thermal conductivity and increasing electron density, which in turn increases the Seebeck coefficient and the electrical conductivity. These combine to then increase the figure of merit for these superlattice films. [Copyright &y& Elsevier]

Abstract: Lithium niobate crystals with various dopents, such as Fe (0.3wt%), Mn (0.1wt%) and Eu (1wt%) ions have been successfully grown using the Czochralski technique. The crystals have been cut in suitable sizes and polished. It is essential to know the concentration and location of dopants in the crystal lattice in order to improve the crystal growth parameters to grow large crystals of LiNbO3 with known impurities. Using Li(p,α) nuclear reaction profile the Li in LiNbO3 crystal was located. Using Rutherford backscattering spectrometry (RBS), the dopants and their concentration as a function of depth were measured. Using channeling, both RBS channeling and (p,α) channeling the lattice location of impurities and the location of Li in the doped crystal could be identified. The energy of the incident protons is maintained at 1.0MeV to avoid neutron production. [Copyright &y& Elsevier]

Abstract: Heavy metals and metalloid ions are found in environmental matrices. The most toxic are lead, cadmium and mercury. These three heavy metals have no biological function and are toxic at all concentrations. Lead is one of the most insidious heavy metals and is introduced into the environment by many different means. It persists in both urban and rural settings, being found in paint chips, pottery, crystal and pharmaceutical and nutritional products. The analysis of heavy elements such as lead in soil is of particular importance [W.T. Sturges, R.M. Harrison, Sci. Total Environ. 44 (3) (1985) 225; M.L. Lepow, L. Bruckman, M. Gillette, S. Markowitz, R. Robino, J. Kapish, Environ. Res. 10 (3) (1975) 415; A.E. Daniels, J.R. Kominsky, P.J. Clark, J. Hazard. Mater. B 87 (2001) 117; G. Hutter, D. Moshman, J. Hazard. Mater. 40 (1995) 1]. In preparing the methods for lead detection in paint, we have used Rutherford backscattering spectrometry (RBS) in order to study the type and amount of heavy metal content in paint samples collected at various sites in the historic campus at A&M University (AAMU). We will show the results of our study with emphasis on comparison of what we learned about presence of lead in paints using our ion beam methods compared with the analysis of lead in paints using cyclic voltammetry. [Copyright &y& Elsevier]

Abstract: In this work we are investigating the structural evolution of tungsten carbide films deposited on silicon carbide (SiC) substrates as a function of temperature. We used thermal evaporation and tungsten carbide (WC) powder as a starting material to produce the thin layer deposition on semi-insulating silicon carbide (6H). Our intended applications are for devices working at 800°C; therefore, our investigations are carried out at 1h intervals of time the samples spent at this temperature. We used Rutherford backscattering spectrometry (RBS) for measuring the stoichiometry and depth profile, atomic force microscopy (AFM) and scanning electron microscopy (SEM) to monitor the surface morphology change, and optical measurements (Raman and optical absorption spectroscopy) to monitor the eventual apparition and evolution of chemically-induced defects of the SiC crystalline lattice. [Copyright &y& Elsevier]

Abstract: The polymer ethylenetetrafluoroethylene (ETFE) is used as anti-adherent coatings for food packages and radiation dosimeters. In this work, we compare the damage induced in ETFE bombarded with 100keV Si ions with that induced by 1MeV proton bombardment. The damage depends on the type, energy and intensity of the irradiation. Irradiated films were analyzed with optical absorption photospectrometry, Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy to determine the chemical nature of the structural changes caused by ion irradiation. Computer simulations were performed to evaluate the radiation damage. [Copyright &y& Elsevier]

Abstract: Glassy polymeric carbon (GPC), which is made from phenolic resins, has a high chemical inertness and is used as high temperature and radiation resistant coatings, as high temperature heat-exchangers, as well as a biomaterial in medicine for the manufacture of heart valves and prosthetic devices [G.M. Jenkins, D. Ila, H. Maleki, Mater. Res. Soc. Symp. Proc. 394 (1995) 181]. GPC is also used for the harsh environment of space, as well as for protective coating against extreme environments such as high temperature, highly ionizing radiation, as well as corrosive environments. In this work, we present the results of our investigation of the influence of the low-energy ion irradiation in glow-discharge plasma on GPC. Chemical changes in GPC prepared at 1000°C were studied using FTIR, micro-Raman spectroscopy and Rutherford backscattering spectrometry (RBS). Porosity changes were monitored through introducing lithium from a molten LiCl salt into GPC and using the (p, α) nuclear reaction analysis (NRA) to measure Li concentration in treated GPC. [Copyright &y& Elsevier]

Abstract: Ion beam induced modification and subsequent characterization of GaAs based hetero-structures (InGaAs/GaAs) have been investigated using ion channeling. The effect of Swift Heavy Ions (SHIs) on the elastic properties of these structures with varying layer thickness and incident ion fluence are discussed. A brief comparison with the results of high resolution XRD is presented. The angular scans of the irradiated samples are found to be broadened compared to the unirradiated samples, suggesting structural changes in the epilayer caused by SHIs. This broadening in thick film is more compared with the thin film. Although these scans are considerably broad, reasonably good minima indicate that the lattice crystallinity is intact. [Copyright &y& Elsevier]

Abstract: Zinc oxide films are deposited at 300K, on SiO2 quartz or glass and glassy polymeric carbon (GPC), by RF magnetron sputtering using zinc oxide target. The stoichiometry of the deposited oxide was determined by Rutherford backscattering spectrometry (RBS) and the optical band gap by optical absorption measurements. Ion irradiation with 5MeV Si ions was performed to enhance the nucleation process of ZnO islands on the SiO2 surface. The first results show that the stoichiometry of ZnO layers is 1 to 1 and the band gap is 3.3eV. Ion bombardment led to a needle-like surface of the ZnO layer, quite different from the effect of annealing of similar samples. Optical properties and surface morphology of Si bombarded ZnO films were analyzed and compared with ZnO annealed films. [Copyright &y& Elsevier]

Abstract: Multilayer thin films were grown sequentially by evaporating solid antimony (III) telluride and bismuth (III) telluride as thermoelectric (TE) materials. The grown multilayer films have a periodic structure consisting of eleven or thirty-nine alternating thin film layers where each layer is 10nm thick. Rutherford backscattering spectrometry (RBS) analysis indicates that the deposited antimony telluride films have the desired stoichiometry of Sb2Te3 and the bismuth telluride films are Bi1.1Te3.0. A 3ω method thermal conductivity measurement system was used to measure the thermal conductivity of the multilayer thin films. 5MeV Si ion implantation was performed to improve the thermal conductivity of the multilayer thin films. Thermoelectric devices were fabricated with the multilayer thin films for the measurement of the cross-plane thermoelectric voltage and determination of Seebeck coefficient. The nanostructured multilayer thin film materials were found to have lower thermal conductivity than their conventional bulk materials, and Si ion implantation can decrease the thermal conductivity of the multilayer thin films. [Copyright &y& Elsevier]

Abstract: Research has shown that the fluorescence decay time can be used to measure temperatures in adverse environments, such as those found in space. Development of space-based phosphor sensors will depend heavily upon research investigating the resistance of phosphors to ionizing radiation. Research completed at the Alabama A&M University Center for Irradiation of Materials (CIM) shows that a 3MeV proton fluence as small as 2.28×1013 mm−2 statistically reduces the ZnS:Mn decay time for temperatures less than 200°C. Reductions in decay time appear to be proportional to increasing 3MeV proton fluence beyond 2.28×1013 mm−2. It is possible that radiation induced dislocations in ZnS:Mn or the formation of sooty carbon in the binder could account for some of these reductions. [Copyright &y& Elsevier]

Abstract: Bi x Te3/Sb2Te3 multilayer thin films were grown as thermoelectric (TE) materials using electron-beam evaporation. Solid antimony (III) telluride and bismuth (III) telluride were used for the growth of Bi x Te3 and Sb2Te3 layers. Rutherford backscattering spectroscopy (RBS) analysis shows that the grown antimony telluride film has the stoichiometry of Sb2Te3 and the bismuth telluride film is Bi1.1Te3. The grown multilayer films have a periodic structure consisting of alternating Bi1.1Te3 and Sb2Te3 layers. The Bi1.1Te3/Sb2Te3 multilayer thin films with five or seven layers were analyzed by RBS. The grown Bi1.1Te3 and Sb2Te3 monolayer thin films and Bi1.1Te3/Sb2Te3 multilayer thin films were bombarded by 5MeV Si ions. The thermal conductivity of the grown films was measured by a 3ω-method thermal conductivity measurement system. The multilayer structure and MeV Si ion bombardment made the films to have a lower thermal conductivity. [Copyright &y& Elsevier]

Abstract: The ethylenetetrafluoroethylene (ETFE) is a polymer formed by alternating ethylene and tetrafluoroethylene segments. It can be applied in the field of medical physics as intra venous catheters and as radiation dosimeters. The increasing application of polymeric materials in technological and scientific fields has motivated the use of surface treatments to modify the physical and chemical properties of polymer surfaces. When a material is exposed to ionizing radiation, it suffers damage leading to surface activation depending on the type, energy and intensity of the applied radiation. In order to determine the radiation damage and the surface activation mechanism ETFE films were bombarded with keV Si and N at various fluences. The bombarded film was also analyzed with optical absorption photospectrometry (OAP), Raman and Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy showing quantitatively the chemical nature at the damage caused by the Si and N bombardment. [Copyright &y& Elsevier]

Abstract: The ethylenetetrafluoroethylene (ETFE) is a polymer formed by alternating ethylene and tetrafluoroethylene segments. It has high impact resistance and useful mechanical properties. ETFE can be used as components of pumps, valves, tie wraps, and electrical components. It can also be applied in the field of medical physics as intra venous catheters and as radiation dosimeter. When a material is exposed to the ionizing radiation, it suffers damage that depends on the type, energy and intensity of the radiation. In order to determine the radiation damage mechanism, ETFE films were bombarded with 1MeV protons to the fluence between 1×1011 and 1×1016 protons/cm2 and the chemical species emitted during the bombardment were measured with residual gas analysis (RGA) and show that HF gas is the entity preferentially emitted. Optical absorption photospectrometry (OAP) and attenuated total reflectometry fourier transform infrared (ATR-FTIR) shows quantitative chemical evidence of the damage. Our results show that damage is detectable at low proton fluence, but damage that can compromise the application in dosimetry occurs only for fluence greater than 1014 protons/cm2. [Copyright &y& Elsevier]

Abstract: We grew 50 periodic SiO2/SiO2 +Ag multi-layers by electron beam deposition technique. The co-deposited SiO2 +Ag layers are 7.26nm, SiO2 buffer layers are 4nm, and total thickness of film was determined as 563nm. We measured the thickness of the layers using in situ thickness monitoring during deposition, and optical interferometry afterwards. The concentration and distribution of Ag in SiO2 were determined using Rutherford backscattering spectrometry (RBS). In order to calculate the dimensionless figure of merit, ZT, the electrical conductivity, thermal conductivity and the Seebeck coefficient of the layered structure were measured at room temperature before and after bombardment with 5MeV Si ions. The energy of the Si ions was chosen such that the ions are stopped deep inside the silicon substrate and only electronic energy due to ionization is deposited in the layered structure. Optical absorption (OA) spectra were taken in the range 200–900nm to monitor the Ag nanocluster formation in the thin layers. [Copyright &y& Elsevier]

Abstract: Implantation of MeV gold, oxygen, carbon ions into GPC alters the surface topography of GPC and enhances the already strong tendency for cells to attach to GPC. We have shown that implantation of silver ions near the surface strongly inhibits cell growth on GPC. Both enhanced adhesion of and inhibition of cell growth are desirable improvements on cardiac implants that have long been successfully fabricated from biocompatible glassy polymeric carbon (GPC). In vitro biocompatibility tests have been carried out with model cell lines to demonstrate that ion beam assisted deposition (IBAD) of silver, as well as silver ion bombardment, can favorably influence the surface of GPC for biomedical applications. [Copyright &y& Elsevier]

Abstract: Titanium for biomedical application stems mainly from its advantageous bulk mechanical properties in combination with a high degree of biocompatibility that is largely attributable to their surface properties. This work is focused on the investigation of surface properties of treated titanium and cell adhesion to titanium treated in glow-discharge plasma. Pure titanium samples (grade 4) were exposed to low-energy ion irradiation in a specially constructed plasma generator, where materials were irradiated by ions of residual gases in vacuum. The ion energy was 1–10keV. The irradiation dose was maintained at 1017 ionscm−2. The irradiation time varied from 5 to 60min. Rutherford backscattering spectrometry (RBS) was used for surface studies. RBS showed the presence of iron on the titanium surface that occurred from the cathode of plasma generator. In vitro biocompatibility test have been carried out with model cell lines (L929 mouse fibroblasts) to demonstrate that low-energy ion irradiation can favorably influence the surface of titanium for biomedical application. Scanning electron microscopy (SEM) was the main tool to demonstrate the cell attachment properties. [Copyright &y& Elsevier]

Abstract: Low energy ion beam bombardment of ethylenetetrafluoroethylene (ETFE) modifies the physical and chemical properties of the polymer surface in ways that enhance or compromise applications in the technological and medical physics fields. When a material is exposed to ionizing radiation, its changes depends on the type, energy and intensity of the applied radiation. In order to determine the nature of the induced radiation changes, ETFE films were bombarded with fluences from 1012 up to 1015 ions/cm2 of keV N and protons. The emission of gaseous species during the bombardments was monitored with a residual gas analyser (RGA). The bombarded films were analysed with optical absorption photospectrometry (OAP), Fourier transform infrared (FTIR) and micro-Raman spectrometries that determine the chemical nature of the structural changes caused by ions bombardment. [Copyright &y& Elsevier]