WorldWideScience

Sample records for beam deposition techniques

  1. Maskless formation of tungsten films by ion beam assisted deposition technique

    International Nuclear Information System (INIS)

    W films were deposited on n-GaAs by ion beam assisted deposition technique using low energy H2+ and Ar+, and film properties and residual damage in the substrate were investigated by measuring x-ray photoemission, current-voltage characteristics and deep level transient spectroscopy. Films with a resistivity of 10-5ohm · cm were formed. This paper reports that it was observed that damage can be reduced using the low energy beams and that Schottky contacts with n-factor of almost 1 and barrier height of 0.88 eV were formed

  2. Site control technique for quantum dots using electron beam induced deposition

    Science.gov (United States)

    Iizuka, Kanji; Jung, JaeHun; Yokota, Hiroshi

    2014-05-01

    To develop simple and high throughput sit definition technique for quantum dots (QDs), the electron beam induced deposition (EBID) method was used as desorption guide of phosphorus atoms form InP substrate. As the results one or a few indium (In) droplets (DLs) were created in the carbon grid pattern by thermal annealing at a temperature of 450°C for 10 min in the ultra high vacuum condition. The size of In DLs was larger than QDs, but arsenide DLs by molecular beam in growth chamber emitted wavelength of 1.028μm at 50K by photoluminescence measurement.

  3. MoSx films deposited on different matrices by ion beam technique

    International Nuclear Information System (INIS)

    MoSx(x = 1.79∼2.34) films of 200 nm thickness are deposited onto brass and C20 steel substrates by the ion beam assisted technique, respectively. Structures and compositions of these films, and changes in valence states of the Mo element are examined by XRD and XPS before and after wear. The lubrication properties and wear resistances for two kinds of samples are evaluated using a pin-on-disk installation in atmosphere at the room temperature. Tribo-wear behaviours and the microstructures between two kinds of samples exhibit obvious differences

  4. Thickness effect on properties of titanium film deposited by d.c. magnetron sputtering and electron beam evaporation techniques

    Indian Academy of Sciences (India)

    Nishat Arshi; Junqing Lu; Chan Gyu Lee; Jae Hong Yoon; Bon Heun Koo; Faheem Ahmed

    2013-10-01

    This paper reports effect of thickness on the properties of titanium (Ti) film deposited on Si/SiO2 (100) substrate using two different methods: d.c. magnetron sputtering and electron beam (e-beam) evaporation technique. The structural and morphological characterization of Ti film were performed using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). XRD pattern revealed that the films deposited using d.c. magnetron sputtering have HCP symmetry with preferred orientation along (002) plane, while those deposited with e-beam evaporation possessed fcc symmetry with preferred orientation along (200) plane. The presence of metallic Ti was also confirmed by XPS analysis. FESEM images depicted that the finite sized grains were uniformly distributed on the surface and AFM micrographs revealed roughness of the film. The electrical resistivity measured using four-point probe showed that the film deposited using d.c. magnetron sputtering has lower resistivity of ∼13 cm than the film deposited using e-beam evaporation technique, i.e. ∼60 cm. The hardness of Ti films deposited using d.c. magnetron sputtering has lower value (∼7.9 GPa) than the film deposited using e-beam technique (∼9.4 GPa).

  5. Nitrogen ion energy dependencies of dielectric constants and compositions of barium carbide-barium nitrate mixed films deposited on silicon wafers by an ion beam assisted deposition technique

    International Nuclear Information System (INIS)

    Thin BaC6-BaN2O4 mixed films with a thickness of 25-60 nm were deposited on Si wafers by evaporating BaCO3 with electron beams and simultaneously applying a mixed beam of N2 molecules and nitrogen ions (an ion beam assisted deposition technique). BaC6 films deposited on Si wafers by evaporating only BaCO3 had low-k values, such as 1.3. In contrast, mixed films containing a small amount of BaC6 and a large amount of BaN2O4 had mild k values, such as 5.6

  6. Microstructure and thermal cycling behavior of CeO2 coatings deposited by the electron beam physical vapor technique

    International Nuclear Information System (INIS)

    Excellent thermal shock resistance is required for thermal protection coatings experiencing high/low temperature cycles. In this paper, the pure ceria oxide coatings were deposited by electron beam physical vapor technique at different power densities. The grain orientation, morphology, hardness and thermal cycling oxidation behavior of CeO2 coatings were systematically studied. The deposition power density has remarkable influence on the preferred crystal orientation and morphology of the coatings. The heating–cooling test cycles from 1000 °C to room temperature indicate that the CeO2 coatings with the columnar structure show excellent thermal shock resistance. The hardness of the CeO2 coating varies with thermal cycling. - Highlights: • Electron-beam physical vapor deposited CeO2 coatings show preferred orientation. • Surface morphology of CeO2 coatings is deeply influenced by the deposition power. • CeO2 coatings with columnar structure exhibit excellent thermal shock resistance. • The hardness increases initially and then decreases during thermal cycling

  7. Investigation of chemical vapour deposition diamond detectors by X- ray micro-beam induced current and X-ray micro-beam induced luminescence techniques

    CERN Document Server

    Olivero, P; Vittone, E; Fizzotti, F; Paolini, C; Lo Giudice, A; Barrett, R; Tucoulou, R

    2004-01-01

    Tracking detectors have become an important ingredient in high-energy physics experiments. In order to survive the harsh detection environment of the Large Hadron Collider (LHC), trackers need to have special properties. They must be radiation hard, provide fast collection of charge, be as thin as possible and remove heat from readout electronics. The unique properties of diamond allow it to fulfill these requirements. In this work we present an investigation of the charge transport and luminescence properties of "detector grade" artificial chemical vapour deposition (CVD) diamond devices developed within the CERN RD42 collaboration, performed by means of X-ray micro-beam induced current collection (XBICC) and X-ray micro- beam induced luminescence (XBIL) techniques. XBICC technique allows quantitative estimates of the transport parameters of the material to be evaluated and mapped with micrometric spatial resolution. In particular, the high resolution and sensitivity of the technique has allowed a quantitati...

  8. Study of Sb/SnO2 bi-layer films prepared by ion beam sputtering deposition technique

    International Nuclear Information System (INIS)

    In the present work, bi-layer thin films of Sb/SnO2 were produced on unheated glass substrates using ion beam sputtering (IBS) technique without post annealing treatment. The thickness of Sb layers was varied from 2 to 10 nm and the Sb layers were deposited on SnO2 layers having thicknesses of 40 nm to 115 nm. The effect of thickness was studied on the morphological, electrical and optical properties. The Sb/SnO2 bi-layer resulted in lowering the electrical resistivity as well as reducing the optical transmittance. However, the optical and electrical properties of the bi-layer films were mainly influenced by the thickness of Sb layers due to progressive transfer in structures from aggregate to continuous films. The bi-layer films show the electrical resistivity of 1.4 × 10−3 Ω cm and an optical transmittance of 26% for Sb film having 10 nm thickness. - Highlights: • Bi-layer Sb/SnO2 structures were synthesized by ion beam sputtering (IBS) technique. • The 6 nm-thick Sb film is a transition region in this study. • The conductivity of the bi-layer films is increased as Sb thickness increases. • The transmittance of the bi-layer films is decreased as Sb thickness increases

  9. The effect of oxygen flow rate on refractive index of aluminum oxide film deposited by electron beam evaporation technique

    Directory of Open Access Journals (Sweden)

    R Shakouri

    2016-02-01

    Full Text Available The effects of oxygen flow rate on refractive index of aluminum oxide film have been investigated. The Al2O3 films are deposited by electron beam on glass substrate at different oxygen flow rates. The substrate was heated to reach  and the temperature was constant during the thin film growth. The transmittance spectrum of samples was recorded in the wavelength 400-800 nm.  Then, using the maxima and minima of transmittance the refractive index and the extinction coefficient of samples were determined. It has been found that if we reduce the oxygen flow, while the evaporation rate is kept constant, the refractive index of Al2O3 films increases. On the other hand, reduced oxygen pressure causes the Al2O3 films to have some absorption.

  10. Oberst beam test technique

    Science.gov (United States)

    Fasana, Alessandro; Garibaldi, Luigi; Giorcelli, Ermanno; Ruzzene, Massimo

    1998-06-01

    The definition of the mechanical properties of viscoelastic materials, i.e. the elastic modulus and the loss factor, is carried out, according to many national and international standards, with many different techniques, both of the resonant and non-resonant type. In this paper we focus our attention on the pros and cons of the resonant technique based on the classical Oberst beam method. When the damping material to be tested is not self-supporting, its properties are determined taking start from the measured modal frequencies and loss factors of a laminated beam, constituted by one or two metallic strips, ideally undamped, and one or two viscoelastic layers. The formulae specified on the standards hold valid under the assumptions of the theory developed by Kerwin, Ungar and Ross and we try in this paper to quantify witch deviation of the results should be expected when moving away from their ideal hypotheses.

  11. TEM investigations of Ni-Cu thin film coatings, obtained by multilayer technique, coevaporation, and ion beam assisted deposition

    International Nuclear Information System (INIS)

    The microstructural aspects of three different thin film coatings of NiCu at the equiatomic concentration are studied by TEM investigations. Those coatings are: multilayered samples, coevaporated samples, and ion beam assisted codeposited samples. In all cases, under certain experimental conditions of irradiation and annealing, an unexpected L10 ordered phase precipitates in the solid solution matrix of NiCu. (author)

  12. Patterned electrochemical deposition of copper using an electron beam

    Directory of Open Access Journals (Sweden)

    Mark den Heijer

    2014-02-01

    Full Text Available We describe a technique for patterning clusters of metal using electrochemical deposition. By operating an electrochemical cell in the transmission electron microscope, we deposit Cu on Au under potentiostatic conditions. For acidified copper sulphate electrolytes, nucleation occurs uniformly over the electrode. However, when chloride ions are added there is a range of applied potentials over which nucleation occurs only in areas irradiated by the electron beam. By scanning the beam we control nucleation to form patterns of deposited copper. We discuss the mechanism for this effect in terms of electron beam-induced reactions with copper chloride, and consider possible applications.

  13. Epitaxial Bi3Fe5O12(001) films grown by pulsed laser deposition and reactive ion beam sputtering techniques

    Science.gov (United States)

    Adachi, N.; Denysenkov, V. P.; Khartsev, S. I.; Grishin, A. M.; Okuda, T.

    2000-09-01

    We report on processing and comparative characterization of epitaxial Bi3Fe5O12 (BIG) films grown onto Gd3(ScGa)5O12[GSGG,(001)] single crystal using pulsed laser deposition (PLD) and reactive ion beam sputtering (RIBS) techniques. A very high deposition rate of about 0.8 μm/h has been achieved in the PLD process. Comprehensive x-ray diffraction analyses reveal epitaxial quality both of the films: they are single phase, exclusively (001) oriented, the full width at half maximum of the rocking curve of (004) Bragg reflection is 0.06 deg for PLD and 0.05 deg for RIBS film, strongly in-plane textured with cube-on-cube film-to-substrate epitaxial relationship. Saturation magnetization 4πMs and Faraday rotation at 635 nm were found to be 1400 Gs and -7.8 deg/μm in PLD-BIG, and 1200 Gs and -6.9 deg/μm in RIBS-BIG. Ferromagnetic resonance (FMR) measurements performed at 9.25 GHz yielded the gyromagnetic ratio γ=1.797×107l/s Oe, 1.826×107 l/s Oe; the constants of uniaxial magnetic anisotropy were Ku*=-8.66×104erg/cm3, -8.60×104 erg/cm3; the cubic magnetic anisotropy K1=-2.7×103 erg/cm3,-3.8×103 erg/cm3; and the FMR linewidth ΔH=25 and 34 Oe for PLD and RIBS films correspondingly. High Faraday rotation, low microwave loss, and low coercive field ⩽40 Oe of BIG/GSGG(001) films promise their use in integrated magneto-optic applications.

  14. Patterned electrochemical deposition of copper using an electron beam

    OpenAIRE

    Mark den Heijer; Ingrid Shao; Alex Radisic; Reuter, Mark C.; Ross, Frances M.

    2014-01-01

    We describe a technique for patterning clusters of metal using electrochemical deposition. By operating an electrochemical cell in the transmission electron microscope, we deposit Cu on Au under potentiostatic conditions. For acidified copper sulphate electrolytes, nucleation occurs uniformly over the electrode. However, when chloride ions are added there is a range of applied potentials over which nucleation occurs only in areas irradiated by the electron beam. By scanning the beam we contro...

  15. Optical constants of e-beam-deposited zirconium dioxide measured in the 55-150 Å wavelength region using the reflectivity technique.

    Science.gov (United States)

    Singh, Amol; Sinha, Mangalika; Gupta, R K; Modi, Mohammed H

    2016-04-20

    In the present study, optical constants of e-beam-deposited zirconium dioxide (ZrO2) thin film are determined in the 55-150 Å soft x-ray wavelength region using the angle-dependent reflectivity technique. Soft x-ray reflectivity measurements are carried out using the reflectivity beamline at the Indus-1 synchrotron radiation source. Derived optical constants (δ and β) are compared with the tabulated values of Henke et al. [http://henke.lbl.gov/optical_constants/asf.html]. It is found that the measured δ values are consistently lower than the tabulated bulk values in the 70-150 Å wavelength region. In this region, the delta values are lower by 19%-24% from the tabulated data. Below the Zr M4 edge (66.3 Å), a deviation in delta values is found as ∼2%-21%. These changes are attributed to growth-related defects (oxygen and voids) and variation in film stoichiometry. To the best of our knowledge, the present study gives the first reported experimental values of optical constants for ZrO2 in the 55-150 Å wavelength region. PMID:27140084

  16. Structural properties and surface wettability of Cu-containing diamond-like carbon films prepared by a hybrid linear ion beam deposition technique

    International Nuclear Information System (INIS)

    Cu-containing diamond-like carbon (Cu-DLC) films were deposited on Si/glass substrate by a hybrid ion beam deposition system. The Cu concentration (0.1–39.7 at.%) in the film was controlled by varying the sputtering current. The microstructure and composition of Cu-DLC films were investigated systematically. The surface topography, roughness and surface wettability of the films were also studied. Results indicated that with increasing the Cu concentration, the water contact angle of the films changed from 66.8° for pure carbon film to more than 104.4° for Cu-DLC films with Cu concentration larger than 24.4 at.%. In the hydrophilic region, the polar surface energy decreased from 30.54 mJ/m2 for pure carbon film to 2.48 mJ/m2 for the film with Cu 7.0 at.%. - Highlights: • Cu-containing diamond-like carbon (DLC) films were deposited by a hybrid ion beam system. • Cu-containing DLC films exhibited a wide range of water contact angle. • The water contact angles vary with the surface energies and surface roughness

  17. Multi-electron beam system for high resolution electron beam induced deposition

    OpenAIRE

    Van Bruggen, M.J.

    2008-01-01

    The development of a multi-electron beam system is described which is dedicated for electron beam induced deposition (EBID) with sub-10 nm resolution. EBID is a promising mask-less nanolithography technique which has the potential to become a viable technique for the fabrication of 20-2 nm structures after 2013, as described by the International Technology Roadmap for Semiconductors (ITRS), or can be used for rapid prototyping in research applications. The key point is to combine the throughp...

  18. Hydrogenated amorphous silicon deposited by ion-beam sputtering

    Science.gov (United States)

    Lowe, V. E.; Henin, N.; Tu, C.-W.; Tavakolian, H.; Sites, J. R.

    1981-01-01

    Hydrogenated amorphous silicon films 1/2 to 1 micron thick were deposited on metal and glass substrates using ion-beam sputtering techniques. The 800 eV, 2 mA/sq cm beam was a mixture of argon and hydrogen ions. The argon sputtered silicon from a pure (7.6 cm) single crystal wafer, while the hydrogen combined with the sputtered material during the deposition. Hydrogen to argon pressure ratios and substrate temperatures were varied to minimize the defect state density in the amorphous silicon. Characterization was done by electrical resistivity, index of refraction and optical absorption of the films.

  19. Focused electron beam induced deposition as a tool to create electron vortices.

    Science.gov (United States)

    Béché, A; Winkler, R; Plank, H; Hofer, F; Verbeeck, J

    2016-01-01

    Focused electron beam induced deposition (FEBID) is a microscopic technique that allows geometrically controlled material deposition with very high spatial resolution. This technique was used to create a spiral aperture capable of generating electron vortex beams in a transmission electron microscope (TEM). The vortex was then fully characterized using different TEM techniques, estimating the average orbital angular momentum to be ∼0.8ℏ per electron with almost 60% of the beam ending up in the ℓ=1 state. PMID:26432987

  20. Effect of discharge current and deposition temperature on roughness and density of NbC films fabricated by ion beam sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, Rajnish, E-mail: rajnish@rrcat.gov.in; Rai, Sanjay, E-mail: rajnish@rrcat.gov.in; Lodha, G. S., E-mail: rajnish@rrcat.gov.in [X-ray optics Section, Indus Synchrotron Utilization Division, Raja Ramanna Center for Advanced Technology, Indore-452013 (India)

    2014-04-24

    NbC films were prepared using Ion beam sputtering system at various discharges current from 0.4 amps to 1.2 amps at room temperature. Effect of temperature on NbC films were also studied by depositing NbC films at various temperatures from room temperature to 200,300,400 and 600°C. X-ray reflectivity (XRR) study shows that surface roughness of the film decreases with decrease in discharge current. The optimum lowest roughness 3.2Å having density 92% of bulk was achieved at discharge current 0.6 amps at 3.0 cm{sup 3}/min Ar gas flow. X-ray study also shows that film roughness decreases with increase in temperature of the film and after a certain temperature it increases with increase in temperature. The lowest surface roughness 2.1Å was achieved at 300°C with density 83% of bulk NbC at constant discharge current 0.6 amps.

  1. Ion plating technique improves thin film deposition

    Science.gov (United States)

    Mattox, D. M.

    1968-01-01

    Ion plating technique keeps the substrate surface clean until the film is deposited, allows extensive diffusion and chemical reaction, and joins insoluble or incompatible materials. The technique involves the deposition of ions on the substrate surface while it is being bombarded with inert gas ions.

  2. Beam shaping for holographic techniques

    Science.gov (United States)

    Laskin, Alexander; Laskin, Vadim; Ostrun, Aleksei

    2014-09-01

    Uniform intensity of laser radiation is very important in holographic and interferometry technologies, therefore transformation of typical Gaussian distribution of a TEM00 laser to flat-top (top hat) is an actual technical task, it is solved by applying beam shaping optics. Holography and interferometry have specific requirements to a uniform laser beam, most important of them are flatness of phase front and extended depth of field. There are different refractive and diffractive beam shaping approaches used in laser industrial and scientific applications, but only few of them are capable to fulfil the optimum conditions for beam quality demanding holography and interferometry. We suggest applying refractive field mapping beam shapers piShaper, which operational principle presumes almost lossless transformation of Gaussian to flat-top beam with flatness of output wavefront, conserving of beam consistency, providing collimated low divergent output beam, high transmittance, extended depth of field, negligible wave aberration, and achromatic design provides capability to work with several lasers with different wavelengths simultaneously. This approach is used in SLM-based technologies of Computer Generated Holography, Dot-Matrix mastering of security holograms, holographic data storage, holographic projection, lithography, interferometric recording of Volume Bragg Gratings. High optical quality of resulting flat-top beam allows applying additional optical components to vary beam size and shape, thus adapting an optical system to requirements of a particular application. This paper will describe design basics of refractive beam shapers and optical layouts of their applying in holographic systems. Examples of real implementations and experimental results will be presented as well.

  3. Lifetime obtained by ion beam assisted deposition

    International Nuclear Information System (INIS)

    We have fabricated green organic light-emitting diodes based on tris-(8-hydroxyquinoline)aluminium (Alq3) thin films. In order to favor the charge carriers transport from the anode, we have deposited a N,N'-diphenyl-N,N'-bis (3-methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) layer (hole transport layer) on a ITO anode. Cathode is obtained with a calcium layer covered with a silver layer. This silver layer is used to protect the other layers against oxygen during the OLED use. All the depositions are performed under vacuum and the devices are not exposed to air during their realisation. In order to improve the silver layer characteristics, we have realized this layer with the ion beam assisted deposition process. The aim of this process is to densify the layer and then reduce the permeation of H2O and O2. We have used argon ions to assist the silver deposition. All the OLEDs optoelectronic characterizations (I = f(V), L = f(V)) are performed in the ambient air. We compare the results obtained with the assisted layer with those obtained with a classical cathode realized by thermal unassisted evaporation. We have realized lifetime measurements in the ambient air and we discuss about the assisted layer influence on the OLEDs performances

  4. Chemical vapour deposited diamonds for dosimetry of radiotherapeutical beams

    Energy Technology Data Exchange (ETDEWEB)

    Bucciolini, M.; Mazzocchi, S. [Firenze Univ., Firenze (Italy). Dipartimento di Fisiopatologia Clinica; INFN, Firenze (Italy); Borchi, E.; Bruzzi, M.; Pini, S.; Sciortino, S. [Firenze Univ., Firenze (Italy). Dipartimento di Energetica; INFN, Firenze (Italy); Cirrone, G.A.P.; Guttone, G.; Raffaele, L.; Sabini, M.G. [INFN, Catania (Italy). Laboratori Nazionali del Sud

    2002-07-01

    This paper deals with the application of synthetic diamond detectors to the clinical dosimetry of photon and electron beams. It has been developed in the frame of INFN CANDIDO project and MURST Cofin. Diamonds grown with CVD (Chemical Vapour Deposition) technique have been studied; some of them are commercial samples while others have been locally synthesised. Experiments have been formed using both on-line and off-line approaches. For the off-line measurements, TL (thermoluminescent) and TSC (thermally stimulated current) techniques have been used.

  5. Chemical vapour deposited diamonds for dosimetry of radiotherapeutical beams

    International Nuclear Information System (INIS)

    This paper deals with the application of synthetic diamond detectors to the clinical dosimetry of photon and electron beams. It has been developed in the frame of INFN CANDIDO project and MURST Cofin. Diamonds grown with CVD (Chemical Vapour Deposition) technique have been studied; some of them are commercial samples while others have been locally synthesised. Experiments have been formed using both on-line and off-line approaches. For the off-line measurements, TL (thermoluminescent) and TSC (thermally stimulated current) techniques have been used

  6. Dual ion beam assisted deposition of biaxially textured template layers

    Energy Technology Data Exchange (ETDEWEB)

    Groves, James R.; Arendt, Paul N.; Hammond, Robert H.

    2005-05-31

    The present invention is directed towards a process and apparatus for epitaxial deposition of a material, e.g., a layer of MgO, onto a substrate such as a flexible metal substrate, using dual ion beams for the ion beam assisted deposition whereby thick layers can be deposited without degradation of the desired properties by the material. The ability to deposit thicker layers without loss of properties provides a significantly broader deposition window for the process.

  7. Physico-chemical study of the focused electron beam induced deposition process

    OpenAIRE

    Bret, Tristan; Hoffmann, Patrik

    2007-01-01

    The focused electron beam induced deposition process is a promising technique for nano and micro patterning. Electrons can be focused in sub-angström dimensions, which allows atomic-scale resolution imaging, analysis, and processing techniques. Before the process can be used in controlled applications, the precise nature of the deposition mechanism must be described and modelled. The aim of this research work is to present a physical and chemical description of the focused electron beam induc...

  8. Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, University of Naples “Federico II”, Napoli (Italy); Bloisi, Francesco, E-mail: bloisi@na.infn.it [SPIN – CNR, Naples (Italy); Department of Physics, University of Naples “Federico II”, Napoli (Italy); Calabria, Raffaela; Califano, Valeria [Istituto Motori – CNR, Naples (Italy); Depero, Laura E. [Department of Mechanical and Industrial Engineering, University of Brescia, Brescia (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, University of Naples “Federico II”, Napoli (Italy); Federici, Stefania [Department of Mechanical and Industrial Engineering, University of Brescia, Brescia (Italy); Massoli, Patrizio [Istituto Motori – CNR, Naples (Italy); Vicari, Luciano R.M. [SPIN – CNR, Naples (Italy); Department of Physics, University of Naples “Federico II”, Napoli (Italy)

    2015-05-01

    Highlights: • A lipase film was deposited with Matrix Assisted Pulsed Laser Evaporation technique. • FTIR spectra show that laser irradiation do not damage lipase molecule. • Laser fluence controls the characteristics of complex structure generated by MAPLE. - Abstract: Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence.

  9. Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

    International Nuclear Information System (INIS)

    Highlights: • A lipase film was deposited with Matrix Assisted Pulsed Laser Evaporation technique. • FTIR spectra show that laser irradiation do not damage lipase molecule. • Laser fluence controls the characteristics of complex structure generated by MAPLE. - Abstract: Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence

  10. An optimized nanoparticle separator enabled by electron beam induced deposition

    International Nuclear Information System (INIS)

    Size-based separations technologies will inevitably benefit from advances in nanotechnology. Direct-write nanofabrication provides a useful mechanism for depositing/etching nanoscale elements in environments otherwise inaccessible to conventional nanofabrication techniques. Here, electron beam induced deposition was used to deposit an array of nanoscale features in a 3D environment with minimal material proximity effects outside the beam-interaction region. Specifically, the membrane component of a nanoparticle separator was fabricated by depositing a linear array of sharply tipped nanopillars, with a singular pitch, designed for sub-50 nm nanoparticle permeability. The nanopillar membrane was used in a dual capacity to control the flow of nanoparticles in the transaxial direction of the array while facilitating the sealing of the cellular-sized compartment in the paraxial direction. An optimized growth recipe resulted which (1) maximized the growth efficiency of the membrane (which minimizes proximity effects) and (2) preserved the fidelity of the spacing between nanopillars (which maximizes the size-based gating quality of the membrane) while (3) maintaining sharp nanopillar apexes for impaling an optically transparent polymeric lid critical for device sealing.

  11. Characteristics of deposition process of thin films by ion-beam evaporation

    International Nuclear Information System (INIS)

    Intense pulsed ion-beam evaporation (IBE) has been proposed as one of the new techniques for the preparation of thin films. To understand the basic process of thin film deposition, the energy deposition on the substrate surface by ablation plasma was measured by using calorimetric technique. The characteristics of prepared thin films were studied with deposition energy. In addition, the substrate temperature was calculated, based on the experimental results, by using one-dimensional simulations only considering heat conduction. (author)

  12. Emittance in particle and radiation beam techniques

    International Nuclear Information System (INIS)

    The author discusses the important and diverse role of the phase space area - the emittance - in the advanced techniques involving interaction of particle and radiation beams. For undulator radiation from unbunched beams, the radiation phase space is diluted from the coherent phase space of the single electron radiation. When the undulator radiation is used as a light source, it is important to minimize the dilution by decreasing the beam emittance and matching the phase space distributions of the particle and the radiation beams. For optical stochastic cooling, on the other hand, the phase space should be maximally mismatched for efficient cooling. In the case particles are bunched to a length much shorter than the radiation wavelength, the emittance appears as an intensity enhancement factor. In the operation of free electron lasers, the phase space matching becomes doubly important, once as the dilution factor in the initial stage of energy modulation and then as the radiation efficiency factor at the end where the beam is density modulated. The author then discusses some of the beam cooling techniques producing smaller emittances, especially the recent suggestions for relativistic heavy ions in storage rings or electron beams in linacs. These are based on the radiative cooling that occurs when particle beams backscatter powerful laser beams

  13. A critical literature review of focused electron beam induced deposition

    Science.gov (United States)

    van Dorp, W. F.; Hagen, C. W.

    2008-10-01

    , there is a limited understanding of the mechanism of electron induced precursor dissociation. In many cases, the deposit composition is not directly dependent on the stoichiometric composition of the precursor and the electron induced decomposition paths can be very different from those expected from calculations or thermal decomposition. The dissociation mechanism is one of the key factors determining the purity of the deposits and a better understanding of this process will help develop electron beam induced deposition into a viable nanofabrication technique.

  14. Ion beam induced conductivity in chemically vapor deposited diamond films

    International Nuclear Information System (INIS)

    Polycrystalline diamond films deposited by the microwave plasma chemical vapor deposition (CVD) technique onto quartz substrates have been irradiated with 100 keV C and 320 keV Xe ions at room temperature and at 200 degree C. The dose dependence of the electrical conductivity measured in situ exhibited complicated, nonmonotonic behavior. High doses were found to induce an increase of up to ten orders of magnitude in the electrical conductivity of the film. The dose dependence of the conductivity for the CVD films was found to be very similar to that measured for natural, type IIa, single-crystal diamonds irradiated under identical conditions. This result suggests that the conduction mechanism in ion beam irradiated polycrystalline CVD diamond films is not dominated by grain boundaries and graphitic impurities as one might have expected, but rather is determined by the intrinsic properties of diamond itself

  15. Sputtering. [as deposition technique in mechanical engineering

    Science.gov (United States)

    Spalvins, T.

    1976-01-01

    This paper primarily reviews the potential of using the sputtering process as a deposition technique; however, the manufacturing and sputter etching aspects are also discussed. Since sputtering is not regulated by classical thermodynamics, new multicomponent materials can be developed in any possible chemical composition. The basic mechanism for dc and rf sputtering is described. Sputter-deposition is described in terms of the unique advantageous features it offers such as versatility, momentum transfer, stoichiometry, sputter-etching, target geometry (coating complex surfaces), precise controls, flexibility, ecology, and sputtering rates. Sputtered film characteristics, such as strong adherence and coherence and film morphology, are briefly evaluated in terms of varying the sputtering parameters. Also described are some of the specific industrial areas which are turning to sputter-deposition techniques.

  16. Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

    Science.gov (United States)

    Aronne, Antonio; Bloisi, Francesco; Calabria, Raffaela; Califano, Valeria; Depero, Laura E.; Fanelli, Esther; Federici, Stefania; Massoli, Patrizio; Vicari, Luciano R. M.

    2015-05-01

    Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence.

  17. Laser controlled deposition of metal microstructures via nondiffracting Bessel beam illumination

    Science.gov (United States)

    Drampyan, Rafael; Leonov, Nikita; Vartanyan, Tigran

    2016-04-01

    The technique of the laser controlled deposition of sodium and rubidium deposits on the sapphire substrate is presented. The metals were deposited on the clean sapphire substrate from the vapor phase contained in the evacuated and sealed cell. We use an axicon to produce a non-diffracting Bessel beam out of the beam got from the cw diode laser with 200 mW power at the wavelength of 532 nm. After 30 minutes of the laser-controlled deposition the substrates were examined in the optical microscope. The obtained metal deposits form the sharp-cut circles with the pitch of 10 μm, coincident with the tens of dark rings of the Bessel beam. Reduction of the laser power leads to the build up of the continuous metal film over the whole substrate.

  18. Highly charged ion beam applied to lithography technique.

    Science.gov (United States)

    Momota, Sadao; Nojiri, Yoichi; Taniguchi, Jun; Miyamoto, Iwao; Morita, Noboru; Kawasegi, Noritaka

    2008-02-01

    In various fields of nanotechnology, the importance of nanoscale three-dimensional (3D) structures is increasing. In order to develop an efficient process to fabricate nanoscale 3D structures, we have applied highly charged ion (HCI) beams to the ion-beam lithography (IBL) technique. Ar-ion beams with various charge states (1+ to 9+) were applied to fabricate spin on glass (SOG) and Si by means of the IBL technique. The Ar ions were prepared by a facility built at Kochi University of Technology, which includes an electron cyclotron resonance ion source (NANOGAN, 10 GHz). IBL fabrication was performed as a function of not only the charge state but also the energy and the dose of Ar ions. The present results show that the application of an Ar(9+) beam reduces the etching time for SOG and enhances the etching depth compared with those observed with Ar ions in lower charged states. Considering the high-energy deposition of HCI at a surface, the former phenomena can be understood consistently. Also, the latter phenomena can be understood based on anomalously deep structural changes, which are remarkable for glasses. Furthermore, it has also been shown that the etching depth can be easily controlled with the kinetic energy of the Ar ions. These results show the possibilities of the IBL technique with HCI beams in the field of nanoscale 3D fabrication. PMID:18315242

  19. Calculation of neutral beam deposition accounting for excited states

    International Nuclear Information System (INIS)

    Large-scale neutral-beam auxillary heating of plasmas has led to new plasma operational regimes which are often dominated by fast ions injected via the absorption of an energetic beam of hydrogen neutrals. An accurate simulation of the slowing down and transport of these fast ions requires an intimate knowledge of the hydrogenic neutral deposition on each flux surface of the plasma. As a refinement to the present generation of transport codes, which base their beam deposition on ground-state reaction rates, a new set of routines, based on the excited states of hydrogen, is presented as mechanism for computing the attenuation and deposition of a beam of energetic neutrals. Additionally, the numerical formulations for the underlying atomic physics for hydrogen impacting on the constiuent plasma species is developed and compiled as a numerical database. Sample results based on this excited state model are compared with the ground-state model for simple plasma configurations

  20. Calculation of neutral beam deposition accounting for excited states

    Energy Technology Data Exchange (ETDEWEB)

    Gianakon, T.A.

    1992-09-01

    Large-scale neutral-beam auxillary heating of plasmas has led to new plasma operational regimes which are often dominated by fast ions injected via the absorption of an energetic beam of hydrogen neutrals. An accurate simulation of the slowing down and transport of these fast ions requires an intimate knowledge of the hydrogenic neutral deposition on each flux surface of the plasma. As a refinement to the present generation of transport codes, which base their beam deposition on ground-state reaction rates, a new set of routines, based on the excited states of hydrogen, is presented as mechanism for computing the attenuation and deposition of a beam of energetic neutrals. Additionally, the numerical formulations for the underlying atomic physics for hydrogen impacting on the constiuent plasma species is developed and compiled as a numerical database. Sample results based on this excited state model are compared with the ground-state model for simple plasma configurations.

  1. Effect of Different Catalyst Deposition Technique on Aligned Multiwalled Carbon Nanotubes Grown by Thermal Chemical Vapor Deposition

    OpenAIRE

    Mohamed Shuaib Mohamed Saheed; Norani Muti Mohamed; Zainal Arif Burhanudin

    2014-01-01

    The paper reported the investigation of the substrate preparation technique involving deposition of iron catalyst by electron beam evaporation and ferrocene vaporization in order to produce vertically aligned multiwalled carbon nanotubes array needed for fabrication of tailored devices. Prior to the growth at 700°C in ethylene, silicon dioxide coated silicon substrate was prepared by depositing alumina followed by iron using two different methods as described earlier. Characterization analysi...

  2. Electron beam instrumentation techniques using coherent radiation

    International Nuclear Information System (INIS)

    Much progress has been made on coherent radiation research since coherent synchrotron radiation was first observed in 1989. The use of coherent radiation as a bunch length diagnostic tool has been studied by several groups. In this paper, brief introductions to coherent radiation and far-infrared measurement are given, the progress and status of their beam diagnostic application are reviewed, different techniques are described, and their advantages and limitations are discussed

  3. Comparison of optical coatings deposited by novel physical and chemical techniques

    International Nuclear Information System (INIS)

    The authors have undertaken a systematic study of various methods of depositing good quality thin films of optically interesting materials by different physical and chemical methods in an effort to identify promising techniques for producing low-absorbing, low-scatter, high damage-threshold coatings. The deposition methods studied include e-beam deposition in a UHV environment, sol-gel processes utilizing hot isostatic pressing (HIP) to densify the films, photochemical deposition using organometallic reagents entrained in inert or potentially reactive gas flows, and ion-beam deposition in a reactive environment. The deposited single-layer films were analyzed using various surface analysis techniques to provide information on film composition, stoichiometry, and impurity level

  4. Techniques for freeing deposited canisters. Final report

    International Nuclear Information System (INIS)

    Four different techniques for removal of the bentonite buffer around a deposited canister have been identified, studied and evaluated: mechanical, hydrodynamical, thermal, and electrical techniques. Different techniques to determine the position of the canister in the buffer have also been studied: mechanical, electromagnetic, thermal and acoustic techniques. The mechanical techniques studied are full-face boring, milling and core-drilling. It is expected that the bentonite can be machined relatively easily. It is assessed that cooling by means of flushing water over the outer surfaces of the tools is not feasible in view of the tendency of bentonite to form a gel. The mechanical techniques are characterized by the potential of damaging the canister, a high degree of complexity, and high requirements of energy/power input. The generated byproduct is solid and cannot be removed by means of flushing. Removal is assessed to be simplest in conjunction with full-face boring and most difficult when coredrilling is applied. The hydrodynamical techniques comprise high-pressure hydrodynamic techniques, where pressures above and below 100 bar, and low pressure hydrodynamical techniques (< 10 bar) are separated. At pressures above 100 bar, a water jet with a diameter of approximately a millimetre cuts through the material. If desired, sand can be added to the jet. At pressures below 100 bar the jet has a diameter of one or a few centimetres. The liquid contains a few percent of salt, which is essential for the efficiency of the process. The flushing is important not only because it removes the modified bentonite but also because it frees previously unaffected bentonite and thereby makes it accessible to chemical modification. All of the hydrodynamical techniques are applicable for freeing the end surface as well as the mantle surface. The degree of complexity and the requirement on energy/power decrease with a decrease in pressure. A significant potential for damaging the

  5. Processes leading to enhanced energy deposition by particle beams

    International Nuclear Information System (INIS)

    Range shortening of electron and proton beams due to target temperature and density effects is calculated. The effect on target hydrodynamics is calculated for a proton beam. The effect of the penetration of an electron beam self magnetic field into the target is shown to cause effective range shortening. Enhanced energy deposition by a pinched electron beam in a foil target is studied numerically and experimentally. The target expansion velocity measured by laser flash photography is used to determine the enhancement factor. Bremsstrahlung measurements are used to study the electron trajectories

  6. Ion beam deposition of calcium hydroxyapatite

    International Nuclear Information System (INIS)

    Calcium hydroxyapatite has been sputtered on glass and Ti-6Al-4V substrates using a 1.5 kV argon ion beam. The films have been examined by X- ray diffraction analysis, energy dispersive spectroscopy, scanning electron microscopy, and adhesion testing. Results of this experimentation are presented

  7. Silicon nitride layers on tool steel produced by ion beam mixing and ion beam assisted deposition

    International Nuclear Information System (INIS)

    Silicon nitride layers on tool steel are produced both, by Kr+ implantation into reactively sputtered Si3N4 on steel (ion beam mixing) and N2+ implantation into evaporated Si on steel (ion beam assisted deposition). Atomic concentration profiles of Fe and Si measured by RBS and XPS show interface mixing. After ion beam assisted deposition complete Si-N compound formation takes place as shown by XPS. Ion beam mixing of Si3N4/steel decreases the etch rate in hydrochloric acid by 50% with respect to uncovered steel. After flash lamp annealing the ion irradiated silicon nitride layer becomes stable against the aggressive acid used. (author)

  8. Use of beam deflection to control an electron beam wire deposition process

    Science.gov (United States)

    Taminger, Karen M. (Inventor); Hofmeister, William H. (Inventor); Hafley, Robert A. (Inventor)

    2013-01-01

    A method for controlling an electron beam process wherein a wire is melted and deposited on a substrate as a molten pool comprises generating the electron beam with a complex raster pattern, and directing the beam onto an outer surface of the wire to thereby control a location of the wire with respect to the molten pool. Directing the beam selectively heats the outer surface of the wire and maintains the position of the wire with respect to the molten pool. An apparatus for controlling an electron beam process includes a beam gun adapted for generating the electron beam, and a controller adapted for providing the electron beam with a complex raster pattern and for directing the electron beam onto an outer surface of the wire to control a location of the wire with respect to the molten pool.

  9. Texture development of CeO2 thin films deposited by ion beam assisted deposition

    International Nuclear Information System (INIS)

    CeO2 thin films were prepared on amorphous quartz glass substrates by the ion beam assisted deposition (IBAD) technique at room temperature. In order to control both the in-plane and out-of-plane texture of the films, a special geometrical arrangement of the ion sources, the target, and the substrate was used. A new concept, considering the role of reflected particles from the target, which we call self-IBAD, was introduced. The structural properties of the CeO2 films were investigated by x-ray diffraction. Good biaxially textured films were obtained with out-of-plane mosaic spreads of 3.0 deg. and in-plane alignment of 10.8 deg. C

  10. Optical and Scratch Resistant Properties of Diamondlike Carbon Films Deposited with Single and Dual Ion Beams

    Science.gov (United States)

    Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

    1993-01-01

    Amorphous diamond-like carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance, frictional, and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

  11. Direct deposition of gold on silicon with focused ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Nebiker, P.W.; Doebeli, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Muehle, R. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Irradiation with ions at very low energies (below 500 eV) no longer induces a removal of substrate material, but the ions are directly deposited on the surface. In this way, gold has been deposited on silicon with focused ion beam exposure and the properties of the film have been investigated with atomic force microscopy and Auger electron spectroscopy. (author) 3 figs., 1 ref.

  12. Nanopillar growth by focused helium ion-beam-induced deposition

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ping; Salemink, Huub W M; Alkemade, Paul F A [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Veldhoven, Emile van; Maas, Diederik J [TNO Science and Industry, Stieltjesweg 1, 2628 CK Delft (Netherlands); Sanford, Colin A [Carl Zeiss SMT, Inc., One Corporation Way, Peabody, MA 01960 (United States); Smith, Daryl A; Rack, Philip D, E-mail: p.f.a.alkemade@tudelft.nl [Department of Material Science and Engineering, University of Tennessee, Knoxville, TN 37996-2200 (United States)

    2010-11-12

    A 25 keV focused helium ion beam has been used to grow PtC nanopillars on a silicon substrate by beam-induced decomposition of a (CH{sub 3}){sub 3}Pt(C{sub P}CH{sub 3}) precursor gas. The ion beam diameter was about 1 nm. The observed relatively high growth rates suggest that electronic excitation is the dominant mechanism in helium ion-beam-induced deposition. Pillars grown at low beam currents are narrow and have sharp tips. For a constant dose, the pillar height decreases with increasing current, pointing to depletion of precursor molecules at the beam impact site. Furthermore, the diameter increases rapidly and the total pillar volume decreases slowly with increasing current. Monte Carlo simulations have been performed with realistic values for the fundamental deposition processes. The simulation results are in good agreement with experimental observations. In particular, they reproduce the current dependences of the vertical and lateral growth rates and of the volumetric deposition efficiency. Furthermore, the simulations reveal that the vertical pillar growth is due to type-1 secondary electrons and primary ions, while the lateral outgrowth is due to type-2 secondary electrons and scattered ions.

  13. Nanopillar growth by focused helium ion-beam-induced deposition

    International Nuclear Information System (INIS)

    A 25 keV focused helium ion beam has been used to grow PtC nanopillars on a silicon substrate by beam-induced decomposition of a (CH3)3Pt(CPCH3) precursor gas. The ion beam diameter was about 1 nm. The observed relatively high growth rates suggest that electronic excitation is the dominant mechanism in helium ion-beam-induced deposition. Pillars grown at low beam currents are narrow and have sharp tips. For a constant dose, the pillar height decreases with increasing current, pointing to depletion of precursor molecules at the beam impact site. Furthermore, the diameter increases rapidly and the total pillar volume decreases slowly with increasing current. Monte Carlo simulations have been performed with realistic values for the fundamental deposition processes. The simulation results are in good agreement with experimental observations. In particular, they reproduce the current dependences of the vertical and lateral growth rates and of the volumetric deposition efficiency. Furthermore, the simulations reveal that the vertical pillar growth is due to type-1 secondary electrons and primary ions, while the lateral outgrowth is due to type-2 secondary electrons and scattered ions.

  14. Cleaning techniques for intense ion beam sources

    International Nuclear Information System (INIS)

    Generation of high power lithium ion beams on the SABRE (1TW) and PBFA-X (20 TW) accelerators have been limited by the parallel acceleration of contaminant ions. during the beam pulse lithium is replaced by protons and carbon ions. This replacement is accompanied by rapid impedance decay of the diode. The contaminant hydrogen and carbon is believed to originate from impurity molecules on the surface and in the bulk of the lithium ion source and its substrate material. Cleaning techniques designed to remove hydrocarbons from the ion source have been employed with some success in test stand experiments and on SABRE. The test stand experiments have shown that a lithium fluoride (LiF) ion source film can accrue dozens of hydrocarbon monolayers on its surface while sitting in vacuum. Application of 13.5 MHz RF discharge cleaning with 90% Ar/10% O2 can significantly reduce the surface hydrocarbon layers on the LiF film. On SABRE, combinations of RF discharge cleaning, anode heating, layering gold between the source film (LiF) and its substrate, and cryogenic cathode cooling produced an increase by a factor of 1.5--2 in the quantity of high energy lithium in the ion beam. A corresponding decrease in protons and carbon ions was also observed. Cleaning experiments on PBFA-X are underway. New designs of contamination resistant films and Li ion sources are currently being investigated

  15. Superconducting nanowires by electron-beam-induced deposition

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Shamashis, E-mail: shamashis.sengupta@u-psud.fr [CSNSM, Univ. Paris-Sud, IN2P3, UMR 8609, F-91405 Orsay Cedex (France); LPS, Univ. Paris-Sud, CNRS, UMR 8502, F-91405 Orsay Cedex (France); Li, Chuan; Guéron, S.; Bouchiat, H. [LPS, Univ. Paris-Sud, CNRS, UMR 8502, F-91405 Orsay Cedex (France); Baumier, Cedric; Fortuna, F. [CSNSM, Univ. Paris-Sud, IN2P3, UMR 8609, F-91405 Orsay Cedex (France); Kasumov, Alik [LPS, Univ. Paris-Sud, CNRS, UMR 8502, F-91405 Orsay Cedex (France); Institute of Microelectronics Technology and High Purity Materials, RAS, ac. Ossipyan, 6, Chernogolovka, Moscow Region 142432 (Russian Federation)

    2015-01-26

    Superconducting nanowires can be fabricated by decomposition of an organometallic gas using a focused beam of Ga ions. However, physical damage and unintentional doping often result from the exposure to the ion beam, motivating the search for a means to achieve similar structures with a beam of electrons instead of ions. This has so far remained an experimental challenge. We report the fabrication of superconducting tungsten nanowires by electron-beam-induced-deposition, with critical temperature of 2.0 K and critical magnetic field of 3.7 T, and compare them with superconducting wires made with ions. This work is an important development for the template-free realization of nanoscale superconducting devices, without the requirement of an ion beam column.

  16. Superconducting nanowires by electron-beam-induced deposition

    International Nuclear Information System (INIS)

    Superconducting nanowires can be fabricated by decomposition of an organometallic gas using a focused beam of Ga ions. However, physical damage and unintentional doping often result from the exposure to the ion beam, motivating the search for a means to achieve similar structures with a beam of electrons instead of ions. This has so far remained an experimental challenge. We report the fabrication of superconducting tungsten nanowires by electron-beam-induced-deposition, with critical temperature of 2.0 K and critical magnetic field of 3.7 T, and compare them with superconducting wires made with ions. This work is an important development for the template-free realization of nanoscale superconducting devices, without the requirement of an ion beam column

  17. Tribological properties of ion beam deposited diamond-like carbon film on silicon nitride

    International Nuclear Information System (INIS)

    The present article reports on the physical characterization and tribological properties of diamond-like carbon (DLC) films deposited on structural Si3N4 substrates. The films were deposited by the direct ion beam deposition technique. The ion beam was produced by plasma discharge of pre-mixed methane and hydrogen gas in a Kaufman-type ion source. The deposited films were found to be amorphous and contained about 70% carbon and 30% hydrogen. The friction coefficient of an uncoated Si3N4 ball on a DLC coated Si3N4 disc starts at about 0.2, then decreases rapidly to 0.1-0.15 with increasing sliding distance. Increasing humidity results in a slight increase in friction coefficient, but a significant decrease in wear factor. The wear factor for the tests at ≅60% rh (relative humidity) are about an order of magnitude smaller than the tests at 3% rh. (orig.)

  18. Solid gold nanostructures fabricated by electron beam deposition

    DEFF Research Database (Denmark)

    Mølhave, Kristian; Madsen, Dorte Nørgaard; Rasmussen, A.M.;

    2003-01-01

    Direct writing with gold by electron beam deposition is a method for rapid fabrication of electrically conducting nanostructures. An environmental scanning electron microscope (ESEM) equipped with a source of the precursor gas dimethylacetylacetonate gold(Ill) was used to fabricate nanoscale tips...

  19. Electronic properties of ion implanted crystalline polymer thin film deposited by ionized cluster beam

    International Nuclear Information System (INIS)

    Polyethylene thin film deposited by the ionized cluster beam deposition technique shows preferential crystal orientation at optimum deposit condition, and the lattice parameters of the crystalline PE film are in good agreement with those of the single crystal PE. The crystalline PE film reveals that the number of side chains is reduced. The conductivity of Li+, Na+ and K+ implanted crystalline PE films has a close correlation with defects generated by ion irradiation, and the conduction mechanism turns out to be the one-dimensional hopping conduction. (orig.)

  20. Laser beam shaping theory and techniques, second edition

    CERN Document Server

    Dickey, Fred M

    2014-01-01

    Laser Beam Shaping: Theory and Techniques addresses the theory and practice of every important technique for lossless beam shaping. Complete with experimental results as well as guidance on when beam shaping is practical and when each technique is appropriate, the Second Edition is updated to reflect significant developments in the field. This authoritative text:Features new chapters on axicon light ring generation systems, laser-beam-splitting (fan-out) gratings, vortex beams, and microlens diffusersDescribes the latest advances in beam profile measurement technology and laser beam shaping using diffractive diffusersContains new material on wavelength dependence, channel integrators, geometrical optics, and optical softwareLaser Beam Shaping: Theory and Techniques, Second Edition not only provides a working understanding of the fundamentals, but also offers insight into the potential application of laser-beam-profile shaping in laser system design.

  1. Microcracking in electron beam deposited scandia-stabilised zirconia electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Lugovy, Mykola; Slyunyayev, Viktor [Institute for Problems of Materials Science, 3 Krzhizhanovskii Str, 03142 Kiev (Ukraine); Steinberger-Wilckens, Robert [Forschungszentrum Jueelich, Jueelich (Germany)

    2009-12-01

    It is the aim of the present work to address some of the aspects of microcracking in electron beam deposited scandia-stabilised zirconia electrolyte applied for solid oxide fuel cells (SOFC) where a thin electrolyte layer is deposited on a relatively thick anode substrate. A model of microcracking for the electrolyte material is proposed which takes into account the statistical distribution of grain sizes, the stress redistribution due to failure of individual structural elements as well as the local criterion of grain fracture. The combination of electron microscopy research with model calculations permits both the specific energy of new surface creation in the electrolyte and critical parameters of the microcracking process to be determined. The annealing-induced electrolyte microcracking discussed in this work corresponds to localised microcracking, where each next structural element fails mainly at an existing microcrack tip. The features of localised microcracking in electron beam deposited scandia-stabilised zirconia electrolyte are analysed. (author)

  2. Dynamic two-dimensional beam-pattern steering technique

    Science.gov (United States)

    Zhou, Shaomin; Yeh, Pochi; Liu, Hua-Kuang

    1993-01-01

    A dynamic two-dimensional laser-beam-pattern steering technique using photorefractive holograms in conjunction with electrically addressed spatial light modulators is proposed and investigated. The experimental results demonstrate the dynamic steering of random combinations of basis beam patterns. The proposed method has the advantages of random beam-pattern combination, good beam intensity uniformity, and higher diffraction efficiency compared with conventional methods.

  3. Cuprous oxide thin films grown by hydrothermal electrochemical deposition technique

    International Nuclear Information System (INIS)

    Semiconducting cuprous oxide films were grown by a hydrothermal electro-deposition technique on metal (Cu) and glass (ITO) substrates between 60 °C and 100 °C. X-ray diffraction studies reveal the formation of cubic cuprous oxide films in different preferred orientations depending upon the deposition technique used. Film growth, uniformity, grain size, optical band gap and photoelectrochemical response were found to improve in the hydrothermal electrochemical deposition technique. - Highlights: • Cu2O thin films were grown on Cu and glass substrates. • Conventional and hydrothermal electrochemical deposition techniques were used. • Hydrothermal electrochemical growth showed improved morphology, thickness and optical band gap

  4. Ion beam assisted deposition of Ti–Si–C thin films

    Directory of Open Access Journals (Sweden)

    A. Twardowska

    2009-11-01

    Full Text Available Purpose: Deposition of hard thin multilayer coatings is a common practice in improving the performance of tools for many different applications. From this aspect Ti3SiC2, due to its lamellar structure and unique combination of properties is a potential interlayer material candidate for thermo-mechanical application.Design/methodology/approach: Multiphase Ti–Si–C thin films were deposited by the ion beam assisted deposition (IBAD technique from a single Ti3SiC2 compound target on an AISI 316L steel substrate. To optimize the deposition process, Monte Carlo simulations were performed; the range of the deposition parameters was determined and then experimentally verified. Scanning and transmission electron microscopies were used to examine the microstructure and quality of the deposited films. Mechanical properties were determined by nanoindentation tests.Findings: The deposited film was flat, smooth and dense with small crystalline particles. The hardness HIT of coated substrates was in the range 2.7 to 5.3 GPa. The average calculated value reduced elastic modulus EIT for coated substrates was 160 GPa. The hardness and reduced elastic modulus for uncoated substrates were HIT = 4.4 GPa and EIT = 250 GPa, respectively.Practical implications: PVD techniques enable low substrate temperature deposition, preferred due to the thermal limitations of the metallic substrates commonly used in industrial applications. The aim of this work is low temperature deposition of Ti-Si-C film, from a single Ti3SiC2 compound target, on 316L steel substrate, using the IBAD technique, known for excellent film connection to the substrate.Originality/value: Ion beam assisted deposition parameters were calculated and experimentally verified.

  5. Ion beam surface treatment: A new technique for thermally modifying surfaces using intense, pulsed ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Stinnett, R.W.; Buchheit, R.G.; Neau, E.L. [and others

    1995-08-01

    The emerging capability to produce high average power (10--300 kW) pulsed ion beams at 0.2{minus}2 MeV energies is enabling us to develop a new, commercial-scale thermal surface treatment technology called Ion Beam Surface Treatment (IBEST). This new technique uses high energy, pulsed ({le}500 ns) ion beams to directly deposit energy in the top 1--20 micrometers of the surface of any material. The depth of treatment is controllable by varying the ion energy and species. Deposition of the energy in a thin surface layer allows melft of the layer with relatively small energies (1--10J/cm2) and allows rapid cooling of the melted layer by thermal conduction into the underlying substrate. Typical cooling rates of this process (109 K/sec) are sufficient to cause amorphous layer formation and the production of non-equilibrium microstructures (nanocrystalline and metastable phases). Results from initial experiments confirm surface hardening, amorphous layer and nanocrystalline grain size formation, corrosion resistance in stainless steel and aluminum, metal surface polishing, controlled melt of ceramic surfaces, and surface cleaning and oxide layer removal as well as surface ablation and redeposition. These results follow other encouraging results obtained previously in Russia using single pulse ion beam systems. Potential commercialization of this surface treatment capability is made possible by the combination of two new technologies, a new repetitive high energy pulsed power capability (0.2{minus}2MV, 25--50 kA, 60 ns, 120 Hz) developed at SNL, and a new repetitive ion beam system developed at Cornell University.

  6. Ion assistance effects on electron beam deposited MgF sub 2 films

    CERN Document Server

    Alvisi, M; Della Patria, A; Di Giulio, M; Masetti, E; Perrone, M R; Protopapa, M L; Tepore, A

    2002-01-01

    Thin films of MgF sub 2 have been deposited by the ion-assisted electron-beam evaporation technique in order to find out the ion beam parameters leading to films of high laser damage threshold whose optical properties are stable under uncontrolled atmosphere conditions. It has been found that the ion-assisted electron-beam evaporation technique allows getting films with optical properties (refraction index and extinction coefficient) of high environmental stability by properly choosing the ion-source voltage and current. But, the laser damage fluence at 308 nm was quite dependent on the assisting ion beam parameters. Larger laser damage fluences have been found for the films deposited by using assisting ion beams delivered at lower anode voltage and current values. It has also been found that the films deposited without ion assistance were characterized by the highest laser damage fluence (5.9 J/cm sup 2) and the lowest environmental stability. The scanning electron microscopy analysis of the irradiated areas...

  7. Kinetics of ion beam deposition of carbon at room temperature

    International Nuclear Information System (INIS)

    Growth rates of carbon films grown by ion beam deposition using methane gas were measured in situ as a function of deposition conditions. The methane pressure dependence of the growth rate was used to measure the cross-section for charge exchange. Variations in deposition rate per incident energetic particle found for each ion energy were related to ion current density. It was found that rates of growth per incident energetic specie were (i) largest for the smallest current densities, (ii) decreased monotonically with increasing current density, and (iii) were consistently larger than can be explained by deposition directly from the energetic flux alone. These observations were interpreted in terms of irradiation-induced surface interactions which promote chemisorption of methane physisorbed from the ambient atmosphere. (orig.)

  8. Recent Advances in Beam Diagnostic Techniques

    Science.gov (United States)

    Fiorito, R. B.

    2002-12-01

    We describe recent advances in diagnostics of the transverse phase space of charged particle beams. The emphasis of this paper is on the utilization of beam-based optical radiation for the precise measurement of the spatial distribution, divergence and emittance of relativistic charged particle beams. The properties and uses of incoherent as well as coherent optical transition, diffraction and synchrotron radiation for beam diagnosis are discussed.

  9. A beam steering technique using dielectric wedges.

    OpenAIRE

    Khan, M. R.

    1995-01-01

    The thesis describes a method of' beam steering aimed at producing a useful amount of deflection of an antenna beam from boresight, by a simple and Inexpensive method. For large antennas, It is difficult, as well as expensive, to steer the beam by more than a few beamwidths. The method studied was developed with particular reference to the beam steering requirements of Direct Broadcast Satellite flat plate antennas. The method involves two dielectric wedges, having cir...

  10. Hydrogen removal from e-beam deposited alumina thin films by oxygen ion beam

    International Nuclear Information System (INIS)

    Hydrogen interstitials and oxygen vacancies defects create energy levels in the band gap of alumina. This limits the application of alumina as a high-k dielectric. A low thermal budget method for removal of hydrogen from alumina is discussed. It is shown that bombardment of alumina films with low energy oxygen ion beam during electron beam evaporation deposition decreases the hydrogen concentration in the film significantly

  11. Electron-beam deposition of vanadium dioxide thin films

    International Nuclear Information System (INIS)

    Developing a reliable and efficient fabrication method for phase-transition thin-film technology is critical for electronic and photonic applications. We demonstrate a novel method for fabricating polycrystalline, switchable vanadium dioxide thin films on glass and silicon substrates and show that the optical switching contrast is not strongly affected by post-processing annealing times. The method relies on electron-beam evaporation of a nominally stoichiometric powder, followed by fast annealing. As a result of the short annealing procedure we demonstrate that films deposited on silicon substrates appear to be smoother, in comparison to pulsed laser deposition and sputtering. However, optical performance of e-beam evaporated film on silicon is affected by annealing time, in contrast to glass. (orig.)

  12. Electron-beam deposition of vanadium dioxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Marvel, R.E.; Appavoo, K. [Vanderbilt University, Interdisciplinary Materials Science Program, Nashville, TN (United States); Choi, B.K. [Vanderbilt University, Department of Electrical Engineering and Computer Science, Nashville, TN (United States); Nag, J. [Vanderbilt University, Department of Physics and Astronomy, Nashville, TN (United States); Haglund, R.F. [Vanderbilt University, Interdisciplinary Materials Science Program, Nashville, TN (United States); Vanderbilt University, Institute for Nanoscale Science and Engineering, Nashville, TN (United States); Vanderbilt University, Department of Physics and Astronomy, Nashville, TN (United States)

    2013-06-15

    Developing a reliable and efficient fabrication method for phase-transition thin-film technology is critical for electronic and photonic applications. We demonstrate a novel method for fabricating polycrystalline, switchable vanadium dioxide thin films on glass and silicon substrates and show that the optical switching contrast is not strongly affected by post-processing annealing times. The method relies on electron-beam evaporation of a nominally stoichiometric powder, followed by fast annealing. As a result of the short annealing procedure we demonstrate that films deposited on silicon substrates appear to be smoother, in comparison to pulsed laser deposition and sputtering. However, optical performance of e-beam evaporated film on silicon is affected by annealing time, in contrast to glass. (orig.)

  13. The use of ion beam techniques in catalysis

    International Nuclear Information System (INIS)

    It has become increasingly obvious recently that ion beam methods can make a significant contribution to the preparation and characterisation of heterogeneous catalysts. Normally such catalysts are composed of one or more metals or compounds dispersed over a high surface area support material, such as alumina or silica. It is important to be able to measure the relative concentrations of the catalytic components (and any associated impurities) over the support, and, to some extent, within the support. Proton Induced X-ray Emission is particularly appropriate for this purpose. It may be used also to identify the presence of poisoning elements which have been responsible for catalyst deactivation. However, one of the most common causes of catalyst deactivation is carbon deposition on to its exposed surfaces. In this case, a particularly useful diagnostic technique is Prompt Nuclear Activation Analysis, since it can be rendered specific for carbon to the exclusion of other associated elements. So far as catalyst preparation is concerned, there are of course many conventional chemical routes: for example, these may involve impregnating the support with suitable catalytic metal salts, thereby utilising the high surface area properties of the support to create the dispersion of the catalytic elements. However, it has now been realised that two ion beam techniques, namely ion implantation and sputtering, provide an alternative method of producing novel catalysts

  14. Facile electron-beam lithography technique for irregular and fragile substrates

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jiyoung; Zhou, Qin; Zettl, Alex, E-mail: azettl@berkeley.edu [Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Kavli Energy NanoSciences Institute at the University of California, Berkeley, California 94720 (United States)

    2014-10-27

    A facile technique is presented which enables high-resolution electron beam lithography on irregularly-shaped, non-planar or fragile substrates such as the edges of a silicon chip, thin and narrow suspended beams and bridges, or small cylindrical wires. The method involves a spin-free dry-transfer of pre-formed uniform-thickness polymethyl methacrylate, followed by conventional electron beam writing, metal deposition, and lift-off. High-resolution patterning is demonstrated for challenging target substrates. The technique should find broad application in micro- and nano-technology research arenas.

  15. Magnetron deposition of TCO films using ion beam

    Science.gov (United States)

    Asainov, O.; Umnov, S.; Chinin, A.

    2015-11-01

    Thin films of tin oxide (TO) were deposited on the glass substrates at room temperature using reactive magnetron sputtering at various oxygen partial pressures. After the deposition the films were irradiated with argon ions beam. The change of the optical and electrical properties of the films depending on the irradiation time was studied. Films optical properties in the range of 300-1100 nm were investigated by photometry as well as their structural properties were studied using X-ray diffraction. Diffractometric research showed that the films, deposited on a substrate, have a crystal structure, and after argon ions irradiation they become quasi-crystalline (amorphous). It was found that the transmission increases proportionally with the irradiation time, but the surface resistance -disproportionally.

  16. Comparison of different experimental techniques used for wax deposition testing

    Energy Technology Data Exchange (ETDEWEB)

    Allenson, Stephen; Johnston, Angela [Nalco Energy Services, Sugar Land, TX (United States)

    2008-07-01

    Crude oils consist of various fractions of hydrocarbons, including n-paraffins. The paraffins precipitate out of oil below the temperature called WAT (wax appearance temperature) and accumulate in flow lines and pipelines causing major transport problems. Prediction of paraffin deposition is, therefore, a key element of flow assurance programs. The purpose of this study was to develop a general and reliable approach to prediction of wax deposition based on a critical comparison of several practical lab techniques. Wax deposition study was conducted on five separate crude oils by using a varying protocols and equipment. One experimental technique was a cold stress test of wax deposition combined with ketone precipitation of waxy paraffin crystals. Another set of experiments were carried out for wax deposits formed on the surface of U-tubes and cold fingers of different designs. A comparison of the effectiveness of several wax inhibitors was conducted for these crude oils by using the selected deposition techniques. In each test method the amount of precipitated wax was recorded and compared. The deposits were characterized by melting point, qualitative and quantitative analysis of the wax components using DSC, SARA and HTGC analyses. Efficiency of paraffin inhibitors was correlated with a profile of n-paraffins distribution in the deposits. The limitations and advantages of different deposition techniques were analyzed and discussed. (author)

  17. Characterization of wax deposition by different experimental techniques - a comparison

    Energy Technology Data Exchange (ETDEWEB)

    Lindeman, Olga; Allenson, Steve

    2006-03-15

    Crude oils consist of various fractions of hydrocarbons, including n-paraffins. The paraffins precipitate out of oil below the temperature called WAT (wax appearance temperature) and accumulate in flow lines causing major transport problems. Prediction of paraffin deposition is, therefore, a key element of flow assurance programs. The purpose of this study was to develop a general and reliable approach to prediction of wax deposition based on a critical comparison of several practical lab techniques. Wax deposition study was conducted on multiple crude oils using various testing protocols and equipment. One experimental technique was a cold stress test of wax deposition combined with ketone precipitation of waxy paraffin crystals. Another set of experiments was carried out for wax deposits formed on the surface of U-tubes and cold fingers of different designs. A comparison of the effectiveness of several wax inhibitors was conducted for these crude oils by using the selected deposition techniques. In each test method the amount of precipitated wax was recorded and compared. The deposits were characterized by melting point, qualitative and quantitative analysis of the wax components using DSC, SARA and HTGC analyses. Efficiency of paraffin inhibitors was correlated with a profile of n-paraffins distribution in the deposits. The limitations and advantages of different deposition techniques were analyzed and discussed. A new test design designated ''cold tube'' is proposed. (Author) (tk)

  18. Ion beam sputter deposition of optical interference coatings

    International Nuclear Information System (INIS)

    Full text: Optical coatings produced by ion beam sputter deposition (IBSD) of oxide layers exhibit low scatter, low absorption, and environmental durability comparable to bulk materials. IBSD utilizes a broad beam ion source to sputter target materials in the presence of oxygen, producing oxide films. The process allows for the independent control of ion beam current, energy, and background gas pressure. The resulting films exhibit low defect densities, high purity, correct stoichiometry, amorphous structure, and high packing density. These properties allow the production of optical coatings with attributes highly desirable in a variety of scientific and industrial applications. Optical cavities utilizing low loss mirrors are used in gravitational wave research, quantum optics, spectroscopy, and numerous other areas of research. Industrial applications of IBSD coatings include the production of mirrors for lasers, including ring laser gyroscopes, corrosion resistant components for semiconductor process tools, and components for optical telecommunications. The IBSD process is easy to automate in contrast to other common processes of deposition which almost always require the presence of skilled operators. The ease of automation is a key factor in the economic viability of IBSD and its recent proliferation. The properties of IBSD coatings and the manufacturability and reproducibility made possible by full automation allow this process to play key enabling roles in research and industry. A review of the IBSD process, its history, and applications will be presented

  19. Substrate heating measurements in pulsed ion beam film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Olson, J.C.; Davis, H.A.; Rej, D.J.; Waganaar, W.J. [Los Alamos National Lab., NM (United States); Tallant, D.R. [Cornell Univ., Ithaca, NY (United States). Materials Science and Engineering Dept.; Thompson, M.O. [Sandia National Labs., Albuquerque, NM (United States)

    1995-05-01

    Diamond-like Carbon (DLC) films have been deposited at Los Alamos National Laboratory by pulsed ion beam ablation of graphite targets. The targets were illuminated by an intense beam of hydrogen, carbon, and oxygen ions at a fluence of 15-45 J/cm{sup 2}. Ion energies were on the order of 350 keV, with beam current rising to 35 kA over a 400 ns ion current pulse. Raman spectra of the deposited films indicate an increasing ratio of sp{sup 3} to sp{sup 2} bonding as the substrate is moved further away from the target and further off the target normal. Using a thin film platinum resistor at varying positions, we have measured the heating of the substrate surface due to the kinetic energy and heat of condensation of the ablated material. This information is used to determine if substrate heating is responsible for the lack of DLC in positions close to the target and near the target normal. Latest data and analysis will be presented.

  20. Fabrication of a microreactor by proton beam writing technique

    International Nuclear Information System (INIS)

    Microreactors are innovative and promising tools in technology nowadays because of their advantages compared to the conventional-scale reactors. These advantages include vast improvements in surface to volume ratio, energy efficiency, reaction speed and yield and increased control of reaction conditions, to name a few examples. The high resolution capability of the micromachining technique utilizing accelerated ion beams in the fabrication technology of microreactors has not yet been taken advantage of. In this work we present the design of a prototype micro-electrochemical cell of 1.5 μL volume (2.5 x 2.5 x 0.240 mm) created with a 3 MeV proton microbeam. The cell can be separated into two half-cells with a suitable membrane applicable to galvanic or fuel cells as well. We deposited gold electrodes on both of the half-cells. The operability of the device was demonstrated by electric current flow between the two electrodes in this micro-electrochemical cell containing a simple electrolyte solution. We used a polycapillary film to separate the two half-cells, hindering the mixing of the anolyte and catholyte solutions. As a result of the minimal mixing caused by the polycapillary film, this cell design can be suitable for electro-synthesis. Due to the high resolution of proton beam writing, it is planned to reduce the dimensions of this kind of microreactor.

  1. Fabrication of a microreactor by proton beam writing technique

    Science.gov (United States)

    Huszank, R.; Szilasi, S. Z.; Vad, K.; Rajta, I.

    2009-06-01

    Microreactors are innovative and promising tools in technology nowadays because of their advantages compared to the conventional-scale reactors. These advantages include vast improvements in surface to volume ratio, energy efficiency, reaction speed and yield and increased control of reaction conditions, to name a few examples. The high resolution capability of the micromachining technique utilizing accelerated ion beams in the fabrication technology of microreactors has not yet been taken advantage of. In this work we present the design of a prototype micro-electrochemical cell of 1.5 μL volume (2.5 × 2.5 × 0.240 mm) created with a 3 MeV proton microbeam. The cell can be separated into two half-cells with a suitable membrane applicable to galvanic or fuel cells as well. We deposited gold electrodes on both of the half-cells. The operability of the device was demonstrated by electric current flow between the two electrodes in this micro-electrochemical cell containing a simple electrolyte solution. We used a polycapillary film to separate the two half-cells, hindering the mixing of the anolyte and catholyte solutions. As a result of the minimal mixing caused by the polycapillary film, this cell design can be suitable for electro-synthesis. Due to the high resolution of proton beam writing, it is planned to reduce the dimensions of this kind of microreactor.

  2. Hemocompatibility of DLC coatings synthesized by ion beam assisted deposition

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Ion beam-assisted diamond-like carbon (DLC) coatings have beenused for growing the human platelet, fibrinogen, and albumin in the control environment in order to assess their hemocompatibility. The hard carbon films were prepared on polymethylmethacrylate (PMMA) at room temperature using ion beam assisted deposition (IBAD). Raman spectroscopic analysis proved that the carbon films on PMMA are diamond-like with a higher fraction of sp\\+3 bonds in the structure of mixed sp\\+2+sp\\+3 bonding. The blood protein adsorption tests showed that DLC coatings can adsorb more albumin and are slightly more fibrinogen than the PMMA chosen as a control sample. The platelets adhered on DLC coatings were reduced significantly in number. These results indicate good hemocompatibility of DLC coatings.

  3. Growth of Ge films by cluster beam deposition

    CERN Document Server

    Xu, J L; Feng, J Y

    2002-01-01

    Ge epitaxial layers with reasonable quality were grown on the Si(1 1 1) substrates by cluster beam deposition (CBD) process. The growth temperature plays a dominant role in the epitaxial growth of Ge films. The substrate temperature for epitaxial growth is about 500 deg. C, which is lower than the reported critical temperature of Ge epitaxial growth by MBE and CVD. A stress induced phase transition of Ge lattice from cubic to tetragonal is also observed in the CBD process, and the mechanism is discussed.

  4. Characterisation of solar cells by ion beam analysis techniques

    International Nuclear Information System (INIS)

    Several ion beam analysis techniques were applied for the characterisation of amorphous (a- Si) and polycrystalline silicon solar cells. Thickness and composition of thin layers in thin film a-Si cells were analysed by RBS (Rutherford backscattering) using 5 MeV Li beam and ERDA (Elastic recoil detection analysis) using 12 MeV C beam. Nuclear microprobe technique IBIC (Ion beam induced charge) was used for imaging a charge collection efficiency of EFG (edge-defined film-fed grown) silicon in attempt to correlate charge loss with a spatial distribution of structural defects in the material. (author)

  5. Functional nickel-based deposits synthesized by focused beam induced processing

    Science.gov (United States)

    Córdoba, R.; Barcones, B.; Roelfsema, E.; Verheijen, M. A.; Mulders, J. J. L.; Trompenaars, P. H. F.; Koopmans, B.

    2016-02-01

    Functional nanostructures fabricated by focused electron/ion beam induced processing (FEBIP/FIBIP) open a promising route for applications in nanoelectronics. Such developments rely on the exploration of new advanced materials. We report here the successful fabrication of nickel-based deposits by FEBIP/FIBIP using bis(methyl cyclopentadienyl)nickel as a precursor. In particular, binary compounds such as nickel oxide (NiO) are synthesized by using an in situ two-step process at room temperature. By this method, as-grown Ni deposits transform into homogeneous NiO deposits using focused electron beam irradiation under O2 flux. This procedure is effective in producing highly pure NiO deposits with resistivity of 2000 Ωcm and a polycrystalline structure with face-centred cubic lattice and grains of 5 nm. We demonstrate that systems based on NiO deposits displaying resistance switching and an exchange-bias effect could be grown by FEBIP using optimized parameters. Our results provide a breakthrough towards using these techniques for the fabrication of functional nanodevices.

  6. Effect of Different Catalyst Deposition Technique on Aligned Multiwalled Carbon Nanotubes Grown by Thermal Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    Mohamed Shuaib Mohamed Saheed

    2014-01-01

    Full Text Available The paper reported the investigation of the substrate preparation technique involving deposition of iron catalyst by electron beam evaporation and ferrocene vaporization in order to produce vertically aligned multiwalled carbon nanotubes array needed for fabrication of tailored devices. Prior to the growth at 700°C in ethylene, silicon dioxide coated silicon substrate was prepared by depositing alumina followed by iron using two different methods as described earlier. Characterization analysis revealed that aligned multiwalled carbon nanotubes array of 107.9 µm thickness grown by thermal chemical vapor deposition technique can only be achieved for the sample with iron deposited using ferrocene vaporization. The thick layer of partially oxidized iron film can prevent the deactivation of catalyst and thus is able to sustain the growth. It also increases the rate of permeation of the hydrocarbon gas into the catalyst particles and prevents agglomeration at the growth temperature. Combination of alumina-iron layer provides an efficient growth of high density multiwalled carbon nanotubes array with the steady growth rate of 3.6 µm per minute for the first 12 minutes and dropped by half after 40 minutes. Thicker and uniform iron catalyst film obtained from ferrocene vaporization is attributed to the multidirectional deposition of particles in the gaseous form.

  7. Radiation effects of electron-beam metal depositions on IGFET's

    International Nuclear Information System (INIS)

    Electron-beam radiation effects on n-channel IGFET parameters were studied. This paper summarizes the resulting surface- and dielectric-radiation effects obtained with a series of experiments incorporating e-gun metal deposition on MOS, MNOS, and SNOS structures. The results are compared with those using resistance-heated metal deposition for various thin-film compositions between the metal and silicon surfaces. A comparison is also made with the effects of controlled direct e-beam irradiation of the structures. The efficiency of quartz and aluminum thin films over MNOS structures, in reducing e-gun radiation effects, is evaluated for double-level metallurgy structures. The effect of different thermal-annealing conditions for offsetting the radiation effects is determined. It is concluded that e-gun metallization causes large negative voltage shifts in MOS, MNOS, and SNOS devices. While MOS threshold shifts are fully ''annealable'', residual MNOS and SNOS V/sub T/ shifts are observed after an anneal of 3500/4500C. Thin films of quartz and aluminum over MOS and MNOS structures effectively reduce radiation effects. Other IGFET parameters are not substantially affected by e-gun radiation

  8. Processing-structure-property relationships in electron beam physical vapor deposited yttria stabilized zirconia coatings

    International Nuclear Information System (INIS)

    The physical and mechanical properties of yttria stabilized zirconia (YSZ) coatings deposited by the electron beam physical vapor deposition technique have been investigated by varying the key process variables such as vapor incidence angle and sample rotation speed. The tetragonal zirconia coatings formed under varying process conditions employed were found to have widely different surface and cross-sectional morphologies. The porosity, phase composition, planar orientation, hardness, adhesion, and surface residual stresses in the coated specimens were comprehensively evaluated to develop a correlation with the process variables. Under transverse scratch test conditions, the YSZ coatings exhibited two different crack formation modes, depending on the magnitude of residual stress. The influence of processing conditions on the coating deposition rate, column orientation angle, and adhesion strength has been established. Key relationships between porosity, hardness, and adhesion are also presented.

  9. Ion beams as a means of deposition and in-situ characterization of thin films and thin film layered structures

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, A.R.; Rangaswamy, M.; Gruen, D.M. (Argonne National Lab., IL (United States)); Lin, Y.P. (Argonne National Lab., IL (United States) Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science); Schultz, J.A. (Ionwerks, Inc., Houston, TX (United States)); Schmidt, H. (Schmidt Instruments, Inc., Houston, TX (United States)); Liu, Y.L. (Argonne National Lab., IL (United States

    1992-01-01

    Ion beam-surface interactions produce many effects in thin film deposition which are similar to those encountered in plasma deposition processes. However, because of the lower pressures and higher directionality associated with the ion beam process, it is easier to avoid some sources of film contamination and to provide better control of ion energies and fluxes. Additional effects occur in the ion beam process because of the relatively small degree of thermalization resulting from gas phase collisions with both the ion beam and atoms sputtered from the target. These effects may be either beneficial or detrimental to the film properties, depending on the material and deposition conditions. Ion beam deposition is particularly suited to the deposition of multi-component films and layered structures, and can in principle be extended to a complete device fabrication process. However, complex phenomena occur in the deposition of many materials of high technical interest which make it desirable to monitor the film growth at the monolayer level. It is possible to make use of ion-surface interactions to provide a full suite of surface analytical capabilities in one instrument, and this data may be obtained at ambient pressures which are far too high for conventional surface analysis techniques. Such an instrument is under development and its current performance characteristics and anticipated capabilities are described.

  10. Ion beams as a means of deposition and in-situ characterization of thin films and thin film layered structures

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, A.R.; Rangaswamy, M.; Gruen, D.M. [Argonne National Lab., IL (United States); Lin, Y.P. [Argonne National Lab., IL (United States)]|[Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science; Schultz, J.A. [Ionwerks, Inc., Houston, TX (United States); Schmidt, H. [Schmidt Instruments, Inc., Houston, TX (United States); Liu, Y.L. [Argonne National Lab., IL (United States)]|[Wisconsin Univ., Milwaukee, WI (United States). Dept. of Materials Science; Auciello, O. [Microelectronics Center of North Carolina, Research Triangle Park, NC (United States); Barr, T. [Wisconsin Univ., Milwaukee, WI (United States). Dept. of Materials Science; Chang, R.P.H. [Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science

    1992-08-01

    Ion beam-surface interactions produce many effects in thin film deposition which are similar to those encountered in plasma deposition processes. However, because of the lower pressures and higher directionality associated with the ion beam process, it is easier to avoid some sources of film contamination and to provide better control of ion energies and fluxes. Additional effects occur in the ion beam process because of the relatively small degree of thermalization resulting from gas phase collisions with both the ion beam and atoms sputtered from the target. These effects may be either beneficial or detrimental to the film properties, depending on the material and deposition conditions. Ion beam deposition is particularly suited to the deposition of multi-component films and layered structures, and can in principle be extended to a complete device fabrication process. However, complex phenomena occur in the deposition of many materials of high technical interest which make it desirable to monitor the film growth at the monolayer level. It is possible to make use of ion-surface interactions to provide a full suite of surface analytical capabilities in one instrument, and this data may be obtained at ambient pressures which are far too high for conventional surface analysis techniques. Such an instrument is under development and its current performance characteristics and anticipated capabilities are described.

  11. Targeting Ion Beam Analysis techniques for gold artefacts

    OpenAIRE

    Demortier, Guy

    2012-01-01

    The present study discusses the best experimental conditions for the quantitative analysis of gold jewellery artefacts by ion beam techniques (PIXE, RBS, PIGE and NRA). Special attention is given to the detection of enhancement or depletion below the surface, down to 10 microns, without any sampling or destruction. PIXE is certainly the most interesting technique for this purpose and the optimal geometrical arrangement of the experiment is described: orientation of the incident beam relative ...

  12. Mechanical properties of monolayer coatings deposited by PVD techniques

    OpenAIRE

    K. Lukaszkowicz; L.A. Dobrzański

    2007-01-01

    Purpose: This research was done to investigate the mechanical properties of monolayer coatings (Ti/CrN, Ti/TiAlN, Ti/ZrN, CrN, TiAl/TiAlN, Zr/ZrN, TiN) deposited by PVD technique (reactive magnetron sputtering method) onto the substrate from the CuZn40Pb2 brass. A thin metallic layer was deposited prior to deposition of ceramic monolithic coatings to improve adhesion.Design/methodology/approach: The microstructure of the coatings was cross section examined using scanning electron microscope. ...

  13. Beam non-uniformity smoothing using density valley formed by heavy ion beam deposition in inertial confinement fusion fuel pellet

    International Nuclear Information System (INIS)

    We study the beam nonuniformity smoothing effect of radiation transport in the density valley formed by an ion-beam deposition in a heavy ion-beam inertial confinement fusion pellet by numerical simulations. The simulation results show that the radiation energy is confined in the density valley, and the beam nonuniformity can be smoothed out by the radiation transport along the density valley. In addition, an estimation for the Rayleigh-Taylor instability during the implosion phase is also presented. (author)

  14. Tungsten trioxide thin films prepared by electrostatic spray deposition technique

    International Nuclear Information System (INIS)

    Tungsten trioxide (WO3) thin films deposited on a Pt-coated alumina substrate using the electrostatic spray deposition (ESD) technique is reported in this paper. As precursor solution, tungsten (VI) ethoxide in ethanol was used. The morphology and the microstructure of the films were studied using scanning electron microscopy coupled with energy dispersive X-ray analysis, transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. Dense to porous morphologies were obtained by tuning the deposition temperature. Impedance spectroscopy and current-voltage measurements were used to study the electrical behaviour of the films in air, in temperature range 300-500 deg. C. The activation energy was estimated from Arrhenius plots. Considering the obtained results, the ESD technique proved to be an effective technique for the fabrication of porous tungsten trioxide thin films

  15. Energy deposition studies for the LBNE beam absorber

    Energy Technology Data Exchange (ETDEWEB)

    Rakhno, Igor L.; Mokhov, Nikolai V.; Tropin, Igor S.

    2015-01-29

    Results of detailed Monte Carlo energy deposition studies performed for the LBNE absorber core and the surrounding shielding with the MARS15 code are described. The model of the entire facility, that includes a pion-production target, focusing horns, target chase, decay channel, hadron absorber system – all with corresponding radiation shielding – was developed using the recently implemented ROOT-based geometry option in the MARS15 code. This option provides substantial flexibility and automation when developing complex geometry models. Both normal operation and accidental conditions were studied. Various design options were considered, in particular the following: (i) filling the decay pipe with air or helium; (ii) the absorber mask material and shape; (iii) the beam spoiler material and size. Results of detailed thermal calculations with the ANSYS code helped to select the most viable absorber design options.

  16. Energy deposition studies for the LBNE beam absorber

    CERN Document Server

    Rakhno, Igor L; Tropin, Igor S

    2015-01-01

    Results of detailed Monte Carlo energy deposition studies performed for the LBNE absorber core and the surrounding shielding with the MARS15 code are described. The model of the entire facility, that includes a pion-production target, focusing horns, target chase, decay channel, hadron absorber system -- all with corresponding radiation shielding -- was developed using the recently implemented ROOT-based geometry option in the MARS15 code. This option provides substantial flexibility and automation when developing complex geometry models. Both normal operation and accidental conditions were studied. Various design options were considered, in particular the following: (i) filling the decay pipe with air or helium; (ii) the absorber mask material and shape; (iii) the beam spoiler material and size. Results of detailed thermal calculations with the ANSYS code helped to select the most viable absorber design options.

  17. Dual ion beam deposition of carbon films with diamondlike properties

    Science.gov (United States)

    Mirtich, M. J.; Swec, D. M.; Angus, J. C.

    1984-01-01

    A single and dual ion beam system was used to generate amorphous carbon films with diamond like properties. A methane/argon mixture at a molar ratio of 0.28 was ionized in the low pressure discharge chamber of a 30-cm-diameter ion source. A second ion source, 8 cm in diameter was used to direct a beam of 600 eV Argon ions on the substrates (fused silica or silicon) while the deposition from the 30-cm ion source was taking place. Nuclear reaction and combustion analysis indicate H/C ratios for the films to be 1.00. This high value of H/C, it is felt, allowed the films to have good transmittance. The films were impervious to reagents which dissolve graphitic and polymeric carbon structures. Although the measured density of the films was approximately 1.8 gm/cu cm, a value lower than diamond, the films exhibited other properties that were relatively close to diamond. These films were compared with diamondlike films generated by sputtering a graphite target.

  18. Cobalt cluster-assembled thin films deposited by low energy cluster beam deposition: Structural and magnetic investigations of deposited layers

    International Nuclear Information System (INIS)

    Cobalt cluster-assembled thin films were deposited on amorphous-carbon-coated copper grids and on silicon substrates at room temperature by low energy cluster beam deposition. Characterizations using high-resolution transmission electronic microscopy and atomic force microscopy reveal randomly stacked agglomerates of 9-11 nm diameter, which are themselves composed of small 3.6 nm diameter fcc cobalt clusters. The films are ferromagnetic up to room temperature and above, which implies that the clusters are exchange coupled. The approach to saturation is analyzed within the random anisotropy model. The values of the exchange coefficient A and the anisotropy constant K then derived are discussed. The temperature dependence of the coercivity below 100 K is discussed in terms of thermal activation effects. All results indicate that the fundamental entity governing the magnetic behaviors is constituted by the 9-11 nm diameter agglomerates rather than by the clusters themselves

  19. Nanostructured component fabrication by electron beam-physical vapor deposition

    Science.gov (United States)

    Singh, Jogender; Wolfe, Douglas E.

    2005-08-01

    Fabrication of cost-effective, nano-grained net-shaped components has brought considerable interest to Department of Defense, National Aeronautics and Space Administration, and Department of Energy. The objective of this paper is to demonstrate the versatility of electron beam-physical vapor deposition (EB-PVD) technology in engineering new nanostructured materials with controlled microstructure and microchemistry in the form of coatings and net-shaped components for many applications including the space, turbine, optical, biomedical, and auto industries. Coatings are often applied on components to extent their performance and life under severe environmental conditions including thermal, corrosion, wear, and oxidation. Performance and properties of the coatings depend upon their composition, microstructure, and deposition condition. Simultaneous co-evaporation of multiple ingots of different compositions in the high energy EB-PVD chamber has brought considerable interest in the architecture of functional graded coatings, nano-laminated coatings, and design of new structural materials that could not be produced economically by conventional methods. In addition, high evaporation and condensate rates allowed fabricating precision net-shaped components with nanograined microstructure for various applications. Using EB-PVD, nano-grained rhenium (Re) coatings and net-shaped components with tailored microstructure and properties were fabricated in the form of tubes, plates, and Re-coated spherical graphite cores. This paper will also present the results of various metallic and ceramic coatings including chromium, titanium carbide (TiC), titanium diboride (TiB2), hafnium nitride (HfN), titanium-boron-carbonitride (TiBCN), and partially yttria stabilized zirconia (YSZ) TBC coatings deposited by EB-PVD for various applications.

  20. Proton-beam technique dates fine wine

    Science.gov (United States)

    Dumé, Belle

    2008-10-01

    Nuclear physicists in France have invented a way to authenticate the vintage of rare wine without needing a sommelier's keen nose or even a corkscrew. The technique, which involves firing high-energy protons at wine bottles, can determine how old the bottles are and even where they come from. The new method could help unmask counterfeit wines - a growing problem in the fine-wine industry, where a bottle can sell for thousands of Euros.

  1. Electron Beam Instrumentation Techniques Using Coherent Radiation

    Science.gov (United States)

    Wang, D. X.

    1997-05-01

    In recent years, there has been increasing interest in short electron bunches for different applications such as short wavelength FELs, linear colliders, advanced accelerators such as laser or plasma wakefield accelerators, and Compton backscattering X-ray sources. A short bunch length is needed to meet various requirements such as high peak current, low momentum spread, high luminosity, small ratio of bunch length to plasma wavelength, or accurate timing. Meanwhile, much progress has been made on photoinjectors and different magnetic and RF bunching schemes to produce very short bunches. Measurement of those short bunches becomes essential to develop, characterize, and operate such demanding machines. Conventionally, bunch duration of short electron bunches is measured by transverse RF deflecting cavities or streak camera. With such devices it becomes very challenging to measure bunch length down to a few hundred femtoseconds. Many frequency domain techniques have been recently developed, based on a relation between bunch profile and coherent radiation spectrum. These techniques provide excellent performance for short bunches. In this paper, coherent radiation and its applications to bunch length measurement will be discussed. A strategy for bunch length control at Jefferson Lab will be presented, which includes a noninvasive coherent synchrotron radiation (CSR) monitor, a zero-phasing technique used to calibrate the CSR detector, and phase transfer measurement used to correct RF phase drifts.

  2. The role of low-energy electrons in focused electron beam induced deposition: four case studies of representative precursors

    Directory of Open Access Journals (Sweden)

    Rachel M. Thorman

    2015-09-01

    Full Text Available Focused electron beam induced deposition (FEBID is a single-step, direct-write nanofabrication technique capable of writing three-dimensional metal-containing nanoscale structures on surfaces using electron-induced reactions of organometallic precursors. Currently FEBID is, however, limited in resolution due to deposition outside the area of the primary electron beam and in metal purity due to incomplete precursor decomposition. Both limitations are likely in part caused by reactions of precursor molecules with low-energy (3, Pt(PF34, Co(CO3NO, and W(CO6. Through these case studies, it is evident that this combination of studies can provide valuable insight into potential mechanisms governing deposit formation in FEBID. Although further experiments and new approaches are needed, these studies are an important stepping-stone toward better understanding the fundamental physics behind the deposition process and establishing design criteria for optimized FEBID precursors.

  3. Obtention of thin depositions by the vacuum evaporation technique

    International Nuclear Information System (INIS)

    The vacuum evaporating technique used to prepare thin depositions, and the technical characteristics of the constructed installation are described. 235U y 238U nuclear target for the fission researches were obtained. Aluminium and gold self-supporting foils were obtained too

  4. Electrochemical characterization and corrosion behaviour of Ni3Al (0.1B) modified by ion beam techniques: a comparative study

    International Nuclear Information System (INIS)

    The corrosion behaviour of Ni3Al(0.1B) treated with different ion beam techniques has been characterized by multisweep cyclic voltammetry and optical microscopy. The results revealed that ion implantation, ion beam mixing and ion beam assisted deposition are very effective to reduce the corrosion and improve the passivation behaviour of specimens in a solution of 1N sulphuric acid. (orig.)

  5. Imaging Techniques for Relativistic Beams: Issues and Limitations

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, Alex H.; Wendt, Manfred; /Fermilab

    2012-02-01

    Characterizations of transverse profiles for low-power beams in the accelerators of the proposed linear colliders (ILC and CLIC) using imaging techniques are being evaluated. Assessments of the issues and limitations for imaging relativistic beams with intercepting scintillator or optical transition radiation screens are presented based on low-energy tests at the Fermilab A0 photoinjector and are planned for the Advanced Superconducting Test Accelerator at Fermilab. We have described several of the issues and limitations one encounters with the imaging of relativistic electron beams. We have reported our initial tests at the A0PI facility and our plans to extend these studies to the GeV scale at the ASTA facility. We also have plans to test these concepts with 23-GeV beams at the FACET facility at SLAC in the coming year. It appears the future remains bright for imaging techniques in ILC-relevant parameter space.

  6. Laser assisted modification and chemical metallization of electron-beam deposited ceria thin films

    International Nuclear Information System (INIS)

    Excimer laser processing is applied for tailoring the surface morphology and phase composition of CeO2 ceramic thin films. E-beam evaporation technique is used to deposit samples on stainless steel and silicate glass substrates. The films are then irradiated with ArF* excimer laser pulses under different exposure conditions. Scanning electron microscopy, optical spectrophotometry, X-ray diffractometry and EDS microanalysis are used to characterize the non-irradiated and laser-processed films. Upon UV laser exposure there is large increase of the surface roughness that is accompanied by photo-darkening and ceria reduction. It is shown that the laser induced changes in the CeO2 films facilitate the deposition of metal nano-aggregates in a commercial copper electroless plating bath. The significance of laser modification as a novel approach for the production of CeO2 based thin film catalysts is discussed.

  7. Mechanical properties of monolayer coatings deposited by PVD techniques

    Directory of Open Access Journals (Sweden)

    K. Lukaszkowicz

    2007-09-01

    Full Text Available Purpose: This research was done to investigate the mechanical properties of monolayer coatings (Ti/CrN, Ti/TiAlN, Ti/ZrN, CrN, TiAl/TiAlN, Zr/ZrN, TiN deposited by PVD technique (reactive magnetron sputtering method onto the substrate from the CuZn40Pb2 brass. A thin metallic layer was deposited prior to deposition of ceramic monolithic coatings to improve adhesion.Design/methodology/approach: The microstructure of the coatings was cross section examined using scanning electron microscope. The residual stress was obtained from the parabolic deflection of the samples, after the coating deposition applying Stoney’s equation. The microhardness and Young’s modulus tests were made on the dynamic ultra-microhardness tester. Tests of the coatings’ adhesion to the substrate material were made using the scratch test.Findings: Obtained results show that all the coatings are in a state of compressive residual stress. The stiffness of the examined coatings is between 224-330 mN/!m, while Young’s modulus is between 258-348 GPa. Concerning the adhesion of the coatings measured by scratch test, it has been stated that the critical load LC2 for coatings, deposited onto the brass ranges from 41 to 57 N.Research limitations/implications: In order to evaluate with more detail the possibility of applying these coatings in tools, further investigations should be concentrated on the determination of the tribological properties of the coatings.Originality/value: The paper contributes to better understanding and recognition the structure of thin coatings deposited by PVD techniques. It should be stressed that the mechanical properties of the PVD coatings obtained in this work are very encouraging and therefore their application for products manufactured at mass scale is possible in all cases where reliable, very hard and abrasion resistant coatings, deposited onto brass substrate are needed.

  8. Techniques for intense-proton-beam profile measurements

    Energy Technology Data Exchange (ETDEWEB)

    Gilpatrick, J.D.

    1998-12-31

    In a collaborative effort with industry and several national laboratories, the Accelerator Production of Tritium (APT) facility and the Spallation Neutron Source (SNS) linac are presently being designed and developed at Los Alamos National Laboratory (LANL). The APT facility is planned to accelerate a 100-mA H{sup +} cw beam to 1.7 GeV and the SNS linac is planned to accelerate a 1- to 4-mA-average, H{sup {minus}}, pulsed-beam to 1 GeV. With typical rms beam widths of 1- to 3-mm throughout much of these accelerators, the maximum average-power densities of these beams are expected to be approximately 30- and 1-MW-per-square millimeter, respectively. Such power densities are too large to use standard interceptive techniques typically used for acquisition of beam profile information. This paper summarizes the specific requirements for the beam profile measurements to be used in the APT, SNS, and the Low Energy Development Accelerator (LEDA)--a facility to verify the operation of the first 20-MeV section of APT. This paper also discusses the variety of profile measurement choices discussed at a recent high-average-current beam profile workshop held in Santa Fe, NM, and will present the present state of the design for the beam profile measurements planned for APT, SNS, and LEDA.

  9. Focused ion beam techniques for fabricating geometrically-complex components and devices.

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Thomas Michael; Adams, David Price; Hodges, V. Carter; Vasile, Michael J.

    2004-03-01

    We have researched several new focused ion beam (FIB) micro-fabrication techniques that offer control of feature shape and the ability to accurately define features onto nonplanar substrates. These FIB-based processes are considered useful for prototyping, reverse engineering, and small-lot manufacturing. Ion beam-based techniques have been developed for defining features in miniature, nonplanar substrates. We demonstrate helices in cylindrical substrates having diameters from 100 {micro}m to 3 mm. Ion beam lathe processes sputter-define 10-{micro}m wide features in cylindrical substrates and tubes. For larger substrates, we combine focused ion beam milling with ultra-precision lathe turning techniques to accurately define 25-100 {micro}m features over many meters of path length. In several cases, we combine the feature defining capability of focused ion beam bombardment with additive techniques such as evaporation, sputter deposition and electroplating in order to build geometrically-complex, functionally-simple devices. Damascene methods that fabricate bound, metal microcoils have been developed for cylindrical substrates. Effects of focused ion milling on surface morphology are also highlighted in a study of ion-milled diamond.

  10. Mechanical properties of monolayer coatings deposited by PVD techniques

    OpenAIRE

    L.A. Dobrzański; K. Lukaszkowicz; A. Zarychta

    2007-01-01

    Purpose: This research was done to investigate the mechanical properties of monolayer coatings (Ti/CrN,Ti/TiAlN, Ti/ZrN, CrN, TiAl/TiAlN, Zr/ZrN, TiN) deposited by PVD technique (reactive magnetron sputteringmethod) onto the substrate from the CuZn40Pb2 brass. A thin metallic layer was deposited prior to depositionof ceramic monolithic coatings to improve adhesion.Design/methodology/approach: The microstructure of the coatings was cross section examined using scanningelectron microscope. The ...

  11. A new pulsed laser deposition technique: scanning multi-component pulsed laser deposition method.

    Science.gov (United States)

    Fischer, D; de la Fuente, G F; Jansen, M

    2012-04-01

    The scanning multi-component pulsed laser deposition (PLD) method realizes uniform depositions of desired coatings by a modified pulsed laser deposition process, preferably with a femto-second laser-system. Multi-component coatings (single or multilayered) are thus deposited onto substrates via laser induced ablation of segmented targets. This is achieved via horizontal line-scanning of a focused laser beam over a uniformly moving target's surface. This process allows to deposit the desired composition of the coating simultaneously, starting from the different segments of the target and adjusting the scan line as a function of target geometry. The sequence and thickness of multilayers can easily be adjusted by target architecture and motion, enabling inter/intra layer concentration gradients and thus functional gradient coatings. This new, simple PLD method enables the achievement of uniform, large-area coatings. Case studies were performed with segmented targets containing aluminum, titanium, and niobium. Under the laser irradiation conditions applied, all three metals were uniformly ablated. The elemental composition within the rough coatings obtained was fixed by the scanned area to Ti-Al-Nb = 1:1:1. Crystalline aluminum, titanium, and niobium were found to coexist side by side at room temperature within the substrate, without alloy formation up to 600 °C. PMID:22559543

  12. Characteristics of MoSx films deposited by ion beam assistance

    International Nuclear Information System (INIS)

    For MoSx films deposited by ion beam assistance, the effect of bombarded ion species, deposition mode, substrate materials and humidity of store environment etc on the properties of these films has been studied. Experimental results indicated that the effect of these factors on films can not be ignored both in the film's deposition and in uses

  13. Large areas elemental mapping by ion beam analysis techniques

    Science.gov (United States)

    Silva, T. F.; Rodrigues, C. L.; Curado, J. F.; Allegro, P.; Moro, M. V.; Campos, P. H. O. V.; Santos, S. B.; Kajiya, E. A. M.; Rizzutto, M. A.; Added, N.; Tabacniks, M. H.

    2015-07-01

    The external beam line of the Laboratory for Material Analysis with Ion Beams (LAMFI) is a versatile setup for multi-technique analysis. X-ray detectors for Particle Induced X-rays Emission (PIXE) measurements, a Gamma-ray detector for Particle Induced Gamma- ray Emission (PIGE), and a particle detector for scattering analysis, such as Rutherford Backscattering Spectrometry (RBS), were already installed. In this work, we present some results, using a large (60-cm range) XYZ computer controlled sample positioning system, completely developed and build in our laboratory. The XYZ stage was installed at the external beam line and its high spacial resolution (better than 5 μm over the full range) enables positioning the sample with high accuracy and high reproducibility. The combination of a sub-millimeter beam with the large range XYZ robotic stage is being used to produce elemental maps of large areas in samples like paintings, ceramics, stones, fossils, and all sort of samples. Due to its particular characteristics, this is a unique device in the sense of multi-technique analysis of large areas. With the continuous development of the external beam line at LAMFI, coupled to the robotic XYZ stage, it is becoming a robust and reliable option for regular analysis of trace elements (Z > 5) competing with the traditional in-vacuum ion-beam-analysis with the advantage of automatic rastering.

  14. Electron-beam-induced deposition and post-treatment processes to locally generate clean titanium oxide nanostructures on Si(100)

    Science.gov (United States)

    Schirmer, M.; Walz, M.-M.; Vollnhals, F.; Lukasczyk, T.; Sandmann, A.; Chen, C.; Steinrück, H.-P.; Marbach, H.

    2011-02-01

    We have investigated the lithographic generation of TiOx nanostructures on Si(100) via electron-beam-induced deposition (EBID) of titanium tetraisopropoxide (TTIP) in ultra-high vacuum (UHV) by scanning electron microscopy (SEM) and local Auger electron spectroscopy (AES). In addition, the fabricated nanostructures were also characterized ex situ via atomic force microscopy (AFM) under ambient conditions. In EBID, a highly focused electron beam is used to locally decompose precursor molecules and thereby to generate a deposit. A drawback of this nanofabrication technique is the unintended deposition of material in the vicinity of the impact position of the primary electron beam due to so-called proximity effects. Herein, we present a post-treatment procedure to deplete the unintended deposits by moderate sputtering after the deposition process. Moreover, we were able to observe the formation of pure titanium oxide nanocrystals (<100 nm) in situ upon heating the sample in a well-defined oxygen atmosphere. While the nanocrystal growth for the as-deposited structures also occurs in the surroundings of the irradiated area due to proximity effects, it is limited to the pre-defined regions, if the sample was sputtered before heating the sample under oxygen atmosphere. The described two-step post-treatment procedure after EBID presents a new pathway for the fabrication of clean localized nanostructures.

  15. Electron-beam-induced deposition and post-treatment processes to locally generate clean titanium oxide nanostructures on Si(100)

    Energy Technology Data Exchange (ETDEWEB)

    Schirmer, M; Walz, M-M; Vollnhals, F; Lukasczyk, T; Sandmann, A; Steinrueck, H-P; Marbach, H [Lehrstuhl fuer Physikalische Chemie II and Interdisciplinary Center for Molecular Materials (ICMM), Universitaet Erlangen-Nuernberg, Egerlandstrasse 3, D-91058 Erlangen (Germany); Chen, C, E-mail: marbach@chemie.uni-erlangen.de [Department of Chemistry, Stanford University, Stanford, CA 94305 (United States)

    2011-02-25

    We have investigated the lithographic generation of TiO{sub x} nanostructures on Si(100) via electron-beam-induced deposition (EBID) of titanium tetraisopropoxide (TTIP) in ultra-high vacuum (UHV) by scanning electron microscopy (SEM) and local Auger electron spectroscopy (AES). In addition, the fabricated nanostructures were also characterized ex situ via atomic force microscopy (AFM) under ambient conditions. In EBID, a highly focused electron beam is used to locally decompose precursor molecules and thereby to generate a deposit. A drawback of this nanofabrication technique is the unintended deposition of material in the vicinity of the impact position of the primary electron beam due to so-called proximity effects. Herein, we present a post-treatment procedure to deplete the unintended deposits by moderate sputtering after the deposition process. Moreover, we were able to observe the formation of pure titanium oxide nanocrystals (<100 nm) in situ upon heating the sample in a well-defined oxygen atmosphere. While the nanocrystal growth for the as-deposited structures also occurs in the surroundings of the irradiated area due to proximity effects, it is limited to the pre-defined regions, if the sample was sputtered before heating the sample under oxygen atmosphere. The described two-step post-treatment procedure after EBID presents a new pathway for the fabrication of clean localized nanostructures.

  16. Electrical measurement techniques for pulsed high current electron beams

    International Nuclear Information System (INIS)

    The advent of high current (1 to 100 kA), moderate energy (>10 MeV), short pulse (1 to 100 ns) electron accelerators used for charged particle beam research has motivated a need to complement standard diagnostics with development of new diagnostic techniques to measure electron beam parameters. A brief survey is given of the diagnostics for measuring beam current, position, size, energy, and emittance. While a broad scope of diagnostics will be discussed, this survey will emphasize diagnostics used on the Experimental Test Accelerator (ETA) and Advanced Test Accelerator (ATA). Focus is placed on diagnostics measuring beam current, position and size. Among the diagnostics discussed are resistive wall current monitors, B/sub theta/ loops, Rogowski coils, Faraday cups, and x-ray wire diagnostics. Operation at higher current levels also increases radiation and electromagnetic pulse interference. These difficulties and methods for circumventing them are also discussed

  17. Structure of monolayer coatings deposited by PVD techniques

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2006-08-01

    Full Text Available Purpose: The aim of the research is the investigation of the structure of coatings deposited by PVD technique(reactive magnetron sputtering method onto the substrate from the CuZn40Pb2 brass.Design/methodology/approach: Microstructure was characterised using optical metallography, scanning andtransmission electron microscopy.Findings: The hard PVD coatings deposited by reactive magnetron sputtering method demonstrate structurecomposed of fine crystallites. In case of the monolayer coatings the columnar structure occurs. Examinations of thePVD coating textures reveal that in most cases they have the binary textures {111} and {100} or {110} and {311}.Research limitations/implications: In order to evaluate with more detail the possibility of applying thesecoatings in tools, further investigations should be concentrated on the determination of the mechanical andtribological properties of the coatings.Originality/value: The paper contributes to better understanding and recognition the structure of thin coatingsdeposited by PVD techniques.

  18. Substrate effects on the electron-beam-induced deposition of platinum from a liquid precursor

    Science.gov (United States)

    Donev, Eugenii U.; Schardein, Gregory; Wright, John C.; Hastings, J. Todd

    2011-07-01

    Focused electron-beam-induced deposition using bulk liquid precursors (LP-EBID) is a new nanofabrication technique developed in the last two years as an alternative to conventional EBID, which utilizes cumbersome gaseous precursors. Furthermore, LP-EBID using dilute aqueous precursors has been demonstrated to yield platinum (Pt) nanostructures with as-deposited metal content that is substantially higher than the purity achieved by EBID with currently available gaseous precursors. This advantage of LP-EBID--along with the ease of use, low cost, and relative innocuousness of the liquid precursors--holds promise for its practical applicability in areas such as rapid device prototyping and lithographic mask repair. One of the feasibility benchmarks for the LP-EBID method is the ability to deposit high-fidelity nanostructures on various substrate materials. In this study, we report the first observations of performing LP-EBID on bare and metal-coated silicon-nitride membranes, and compare the resulting Pt deposits to those obtained by LP-EBID on polyimide membranes in terms of nucleation, morphology, size dependence on electron dose, and purity.

  19. A new beam deflection angle amplification technique for mirage detection

    OpenAIRE

    Yarai, A.; Fukunaga, Y; Sakamoto, K; Nakanishi, T.

    1994-01-01

    A new technique has been developed for amplification of the photothermal beam deflection angle for mirage detection. This technique, based on a very simple operating principle, uses a cylindrical reflection mirror. The use of a new amplifier provided a signal-to-noise ratio approximately 10 times that obtained without the amplifier for equipment of the same size. By using the new amplifier, a mirage signal was obtained when a transistor array processed on a silicon wafer was measured.

  20. Effect of deposition technique of Ni on the perpendicular magnetic anisotropy in Co/Ni multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Akbulut, S., E-mail: sakbulut@gtu.edu.tr [Gebze Technical University, Physics Department, Istanbul Cad, PK 41400 Gebze/Kocaeli (Turkey); Akbulut, A. [Gebze Technical University, Physics Department, Istanbul Cad, PK 41400 Gebze/Kocaeli (Turkey); Özdemir, M. [Marmara University, Physics Department, Göztepe, Istanbul (Turkey); Yildiz, F., E-mail: fyildiz@gtu.edu.tr [Gebze Technical University, Physics Department, Istanbul Cad, PK 41400 Gebze/Kocaeli (Turkey)

    2015-09-15

    The perpendicular magnetic anisotropy (PMA) of Si/Pt 3.5/(Co 0.3/Ni 0.6){sub n} /Co 0.3/ Pt 3 (all thicknesses are nm) multilayers were investigated for two different sample sets by using ferromagnetic resonance (FMR) and magnetooptic Kerr effect (MOKE) techniques. In the first sample set all layers (buffer, cap, Co and Ni) were grown by magnetron sputtering technique while in the second sample set Ni sub-layers were grown by molecular beam epitaxy (MBE) at high vacuum. Apart from deposition technique of Ni, all other parameters like thicknesses and growth rates of each layers are same for both sample sets. Multilayers in these two sample sets display PMA in the as grown state until a certain value of bilayer repetition (n) and the strength of PMA decreases with increasing n. Magnetic easy axis's of the multilayered samples switched from film normal to the film plane when n is 9 and 5 for the first and second sample sets, respectively. The reason for that, PMA was decreased due to increasing roughness with increasing n. This was confirmed by X Ray Reflectivity (XRR) measurements for both sample sets. Moreover, in the first sample set coercive field values are smaller than the second sample set, which means magnetic anisotropy is lower than the latter one. This stronger PMA is arising due to existence of stronger Pt (111) and Co/Ni (111) textures in the second sample set. - Highlights: • Effect of deposition techniques for Ni sub-layers on magnetic properties in [Co/Ni]{sub n} multilayered films was studied. • Ni sub-layers were deposited by two different techniques, molecular beam epitaxy (MBE) and magnetron sputtering. • Spin reorientation thickness and magnitude of the anisotropy are strongly depending on growing techniques.

  1. Optical fiber sensors fabricated by the focused ion beam technique

    DEFF Research Database (Denmark)

    Yuan, Scott Wu; Wang, Fei; Bang, Ole

    2012-01-01

    Focused ion beam (FIB) is a highly versatile technique which helps to enable next generation of lab-on-fiber sensor technologies. In this paper, we demonstrate the use application of FIB to precisely mill the fiber taper and end facet of both conventional single mode fiber (SMF) and photonic...

  2. Photo-metalorganic molecular-beam epitaxy: A new epitaxial growth technique

    Energy Technology Data Exchange (ETDEWEB)

    Tokumitsu, E.; Yamada, T.; Konagai, M.; Takahashi, K.

    1989-05-01

    Metalorganic molecular-beam epitaxy (MOMBE) combines many important advantages of molecular-beam epitaxy and metalorganic chemical vapor deposition. One of the most important features of MOMBE is that photochemical reaction can be used and we can call this new technique ''photo-MOMBE.'' Triisobutylaluminum (TIBA) has been used in photo-MOMBE instead of triethylaluminum (TEA) as a new aluminum source in order to enhance the photodecomposition. The optical absorption coefficient of TIBA for 193 nm was found to be three times greater than that of TEA. Selective deposition of Al, AlAs, and GaAlAs was carried out by using an ArF excimer laser. The Al mole fraction of GaAlAs ternary alloy grown with the excimer laser irradiation was greater than that of the film grown without the laser irradiation.

  3. Photo-metalorganic molecular-beam epitaxy: A new epitaxial growth technique

    International Nuclear Information System (INIS)

    Metalorganic molecular-beam epitaxy (MOMBE) combines many important advantages of molecular-beam epitaxy and metalorganic chemical vapor deposition. One of the most important features of MOMBE is that photochemical reaction can be used and we can call this new technique ''photo-MOMBE.'' Triisobutylaluminum (TIBA) has been used in photo-MOMBE instead of triethylaluminum (TEA) as a new aluminum source in order to enhance the photodecomposition. The optical absorption coefficient of TIBA for 193 nm was found to be three times greater than that of TEA. Selective deposition of Al, AlAs, and GaAlAs was carried out by using an ArF excimer laser. The Al mole fraction of GaAlAs ternary alloy grown with the excimer laser irradiation was greater than that of the film grown without the laser irradiation

  4. Realization of YBCO and BSCCO thin films using simple and reliable deposition techniques

    International Nuclear Information System (INIS)

    In situ YBa2Cu3O7 thin films were fabricated using a mixed codeposition technique in which the authors simultaneously sputtered from an YCu3 target and thermally evaporated metallic Ba. During the deposition the substrates were held at a temperature of 650 degrees C in presence of an O2 partial pressure of 2 x 10-3 mbar. After the deposition the substrates temperature was decreased to 450 degrees C with an O2 pressure of ∼103 mbar for two hours. The as deposited samples on sapphire were superconducting with an onset at ∼ 90 K and zero resistance at ∼60 K. Moreover using an electron beam evaporation technique the authors obtained good films of both the YBCO and BSCCO compounds. The YBCO thin films were grown starting from a weighted amount of YCu3 and Ba held in two crucibles where the electron beam was splitted with a suitable frequency. An ex situ annealing process was needed to obtain superconducting films. The BSCCO thin films were obtained by a complete evaporation of bulk pellets with different compositions. After an annealing at 850 degrees C the films were superconducting with a Tc (R = 0) for ∼70 K on MgO substrates and ∼50 K on sapphire substrates. In this paper preliminary measurements of the critical current vs. temperature are reported

  5. Beam-Induced Deposition of Thin Metallic Films.

    Science.gov (United States)

    Funsten, Herbert Oliver, III

    1990-01-01

    Ion and electron beam induced deposition (BID) of thin (1 μm), conductive films is accomplished by dissociating and removing the nonmetallic components of an adsorbed, metal-based, molecular gas. Current research has focused primarily on room temperature (monolayer adsorption) BID using electrons and slow, heavy ions. This study investigates low temperature (50 to 200 K) BID in which the condensation of the precursor gases (SnCl _4 and (CH_3) _4Sn) maximizes the efficiency of the incident radiation which can create and remove nonmetallic fragments located several monolayers below the film surface. The desired properties of the residual metallic films are produced by using as incident radiation either nuclear (35 keV Ar ^+) or electronic (2 keV electrons, 25 keV H^+, or 50 keV H ^+) energy loss mechanisms. Residual films are analyzed ex situ by Scanning Electron Microscopy (SEM), thickness measurements, resistivity measurements, Rutherford Backscattering Spectroscopy (RBS), and infrared spectroscopy. Low temperature BID film growth models, which are derived from both a computer simulation and a mathematical analysis, closely agree. Both the fragmentation and sputtering cross sections for a particular ion and energy are derived for films created from (CH_3) _4Sn. The fragmentation cross section, which corresponds to film growth, is roughly related to the electronic stopping power by the 1.9 power. The loss of carbon in films which were created from (CH_3) _4Sn is strongly dependent on the nuclear stopping power. Film growth rates for low temperature BID have been found to be 10 times those of room temperature BID.

  6. Ion-beam-assisted deposition and ion beam synthesis of wear resistant coatings on technical surfaces

    International Nuclear Information System (INIS)

    An ion implanter with a non-mass-separated ion beam, already used for experiments as well as industrial applications, was equipped with an electron-gun evaporator to allow for simultaneous or sequential implantation and coating. Using this equipment, ion-beam-assited deposition (IBAD) of different layers, and in particular the formation of layers of TiN on steel with very good adhesion, was possible. To produce TiN, titanium was evaporated and nitrogen was implanted. The maximum growth rate of the TiN films was 1 nm s-1. Examinations showed superior wear properties in comparison with ion-plated layers and an unusual high Knoop microhardness. Under certain experimental conditions, the stoichiometric ratio was found to be 1:1 even if the ion density was varied slightly, making the IBAD process easily controllable. The layers did not have the yellow color typical of ion-plated TiN layers but were neutral gray. Nevertheless, electron diffraction investigations confirmed the typical crystalline structure of TiN. Analytical investigations were performed and compared with those of ion-plated TiN. Details of the equipment, including operation conditions, as well as experimental results of film properties will be reported. (orig.)

  7. Group velocity delay spectroscopy technique for industrial monitoring of electron beam induced vapors

    Energy Technology Data Exchange (ETDEWEB)

    Benterou, J J; Berzins, L V; Sharma, M N

    1998-09-24

    Spectroscopic techniques are ideal for characterization and process control of electron beam generated vapor plumes. Absorption based techniques work well for a wide variety of applications, but are difficult to apply to optically dense or opaque vapor plumes. We describe an approach for monitoring optically dense vapor plumes that is based on measuring the group velocity delay of a laser beam near an optical transition to determine the vapor density. This technique has a larger dynamic range than absorption spectroscopy. We describe our progress towards a robust system to monitor aluminum vaporization in an industrial environment. Aluminum was chosen because of its prevalence in high performance aircraft alloys. In these applications, composition control of the alloy constituents is critical to the deposition process. Data is presented demonstrating the superior dynamic range of the measurement. In addition, preliminary data demonstrating aluminum vapor rate control in an electron beam evaporator is presented. Alternative applications where this technique could be useful are discussed. Keywords: Group velocity delay spectroscopy, optical beat signal, optical heterodyne, index of refraction, laser absorption spectroscopy, external cavity diode laser (ECDL), electron beam vaporization, vapor density, vapor phase manufacturing, process control

  8. Structural and growth aspects of electron beam physical vapor deposited NiO-CeO2 nanocomposite films

    International Nuclear Information System (INIS)

    Deposition of composite materials as thin film by electron beam physical vapor deposition technique (EB-PVD) still remains as a challenge. Here, the authors report the deposition of NiO-CeO2 (30/70 wt. %) composites on quartz substrate by EB-PVD. Two NiO-CeO2 nanocomposite targets—one as green compact and the other after sintering at 1250 °C—were used for the deposition. Though the targets varied with respect to physical properties such as crystallite size (11–45 nm) and relative density (44% and 96%), the resultant thin films exhibited a mean crystallite size in the range of 20–25 nm underlining the role of physical nature of deposition. In spite of the crystalline nature of the targets and similar elemental concentration, a transformation from amorphous to crystalline structure was observed in thin films on using sintered target. Postannealing of the as deposited film at 800 °C resulted in a polycrystalline structure consisting of CeO2 and NiO. Deposition using pure CeO2 or NiO as target resulted in the preferential orientation toward (111) and (200) planes, respectively, showing the influence of adatoms on the evaporation and growth process of NiO-CeO2 composite. The results demonstrate the influence of electron beam gun power on the adatom energy for the growth process of composite oxide thin films

  9. Effects of oxygen pressure in reactive ion beam sputter deposition of zirconium oxides

    International Nuclear Information System (INIS)

    The mechanism of reactive ion beam sputtering is investigated. The experimental results indicate that the pressure decrease during sputtering, the properties of Zr--O films, and the deposition rate are all strongly influenced by oxygen partial pressure. A new model which takes into account the gettering action of the deposition material and deals with the number of sputtered and gaseous particles is presented for reactive ion beam sputtering of metal. The theoretical values are compared with experimental results of the reactive ion beam sputtering. It is found that the calculated values agree extremely well with the oxygen partial pressure decrease and the deposition rate measured experimentally

  10. Magnetotransport properties of high-quality cobalt nanowires grown by focused-electron-beam-induced deposition

    International Nuclear Information System (INIS)

    High-quality cobalt nanowires have been grown by focused-electron-beam-induced deposition (FEBID) and their magnetic and transport properties determined. The nanowires contain up to about 95% Co atomic percentage, as measured by EDX spectroscopy, which remarkably represents a high value compared with other metal deposits grown by the same technique. The Co content has been found to correlate with the beam current used for the growth. The magnetotransport properties have been studied on individual nanowires through 4-probe measurements. For the nanowires with the highest Co content, the resistivity at room temperature is low (∼40 μΩ cm), and shows metallic temperature dependence. The magnetotransport properties clearly demonstrate the ferromagnetic nature of the nanowire, with a saturation magnetization of Ms = 1329 ± 20 emu cm-3, very close to the bulk one. Due to the local character of this type of growth at targeted places and its high lateral resolution, these results pave the way for the creation of magnetic nanostructures and devices with the full potentiality of high-quality Co.

  11. Diffusion and Interface Reaction of Cu/Si(100) Films Prepared by Cluster Beam Deposition

    Institute of Scientific and Technical Information of China (English)

    GAO Xing-Xin; JIA Yan-Hui; LI Gong-Ping; CHO Seong-Jin; KIM Hee

    2011-01-01

    Cu thin films are deposited on Si(100) substrates by neutral cluster beams and ionized cluster beams. The atomic diffusion and interface reaction between the Cu films and the Si substrates of as-deposited and annealed at different temperatures(230℃, 450℃, 500℃and 600℃) are investigated by Rutherford backscatteringspectrometry(RBS)and x-ray diffraction(XRD). Some significant results are obtained on the following aspects:(1) For the Cu/Si(100)samples prepared by neutral cluster beams and ionized cluster beams at Va=0 kV, atomic diffusion phenomena are observed clearly in the as-deposited samples. With the increase of annealing temperature, the interdiffusion becomes more apparent. However, the diffusion intensities of the RBS spectra of the Cu/Si(100) films using neutral cluster beams are always higher than that of the Cu/Si(100) films using ionized cluster beams at Va=OkV in the as-deposited and samples annealed at the same temperature. The compound of Cu3Si is observed in the as-deposited samples.(2) For the Cu/Si(100) samples prepared by ionized cluster beams at Va=1, 3, 5 kV,atomic diffusion phenomena are observed in the as-deposited samples at Va=1, 5 kV. For the samples prepared at Va=3 kV, the interdiffusion phenomenon is observed until 500℃ annealing temperature. The reason for the difference is discussed.

  12. Fabrication of speckle patterns by focused ion beam deposition and its application to micro-scale residual stress measurement

    Science.gov (United States)

    Zhu, Ronghua; Xie, Huimin; Xue, Yunfei; Wang, Liang; Li, YanJie

    2015-09-01

    This paper deals with the characterization of influence parameters on the fabrication of speckle patterns using FIB deposition. In many manufacturing processes the presence of residual stress is disturbing, and can significantly affect the mechanical properties of materials and structures. Digital image correlation (DIC) is validated to be an effective approach for the determination of micro-scale residual stress under the dual-beam microscope (FIB-EB). Considering the high-quality micro-scale speckle pattern is the prerequisite in DIC measurement, the influence parameters on the deposited speckle patterns, such as the quality of the speckle template, total deposition time, ion beam current density, and dwell time, are primarily discussed. Moreover, in the measurement of residual stress, the integrated fabrication technique under the FIB-EB dual-beam system is also explained, covering the following steps: fabrication of the speckle pattern by FIB deposition, slot milling for stress release by FIB, high-resolution SEM imaging before and after stress release as well as the deformation analysis by DIC. As application, the optimized micro-scale speckle patterns are deposited on the surface of laser shock peened metallic glass, and the residual stress distribution on the sample surface is successfully measured.

  13. Laser beam soldering of fine-pitch technology packages with solid solder deposits

    Science.gov (United States)

    Pucher, Hans-Joerg; Glasmacher, Mathias; Geiger, Manfred

    1996-04-01

    Micro electronics is a key technology attracting the attention of information, communication, automation and data processing technologies. Ongoing miniaturization combined with an increasing number of I/Os has inevitably lead to ever finer lead geometries. Therefore the demands put upon the surface mount technology are increasing continuously. Processing of high lead count fine pitch packages, for example those which are applied in high-capacity computers, has not increased the demands put upon the assembly process only, but also on the connecting techniques. By reflow soldering with laser beam radiation the benefits from the tool `laser beam' are used extensively, for example contact and force free processing, strictly localized heating and the good controllability thereof, formation of fine crystalline and homogeneous structures, etc. Within the scope of this paper the fundamentals of laser beam soldering are discussed for fine pitch lead frames (pitch 300 micrometers ) for plastic packages, made by a modified CuFe2P alloy with a 5 micrometers Sn90Pb plating, on solid solder depths (Sn63Pb) performed by the so called High-Pad process. These investigations are unique in the field of laser beam soldering and are carried out by means of a Nd:YAG-laser. A pyrometer is used for detection of the emission of the temperature radiation of the joining area for process control. The additional use of a high-speed camera gives a detailed description of the melting and wetting process. The influence of laser beam parameters and the volume of the solid solder deposits on the joining result are presented.

  14. Mechanical properties of monolayer coatings deposited by PVD techniques

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2007-01-01

    Full Text Available Purpose: This research was done to investigate the mechanical properties of monolayer coatings (Ti/CrN,Ti/TiAlN, Ti/ZrN, CrN, TiAl/TiAlN, Zr/ZrN, TiN deposited by PVD technique (reactive magnetron sputteringmethod onto the substrate from the CuZn40Pb2 brass. A thin metallic layer was deposited prior to depositionof ceramic monolithic coatings to improve adhesion.Design/methodology/approach: The microstructure of the coatings was cross section examined using scanningelectron microscope. The residual stress was obtained from the parabolic deflection of the samples, after the coatingdeposition applying Stoney’s equation. The microhardness and Young’s modulus tests were made on the dynamicultra-microhardness tester. Tests of the coatings’ adhesion to the substrate material were made using the scratch test.Findings: Obtained results show that all the coatings are in a state of compressive residual stress. The stiffnessof the examined coatings is between 224 ÷ 330 mN/μm, while Young’s modulus is between 258 ÷ 348 GPa.Concerning the adhesion of the coatings measured by scratch test, it has been stated that the critical load LC2for coatings, deposited onto the brass ranges from 41 to 57 N.Research limitations/implications: In order to evaluate with more detail the possibility of applying thesecoatings in products used in the building and power industries, further investigations should be concentrated onthe determination of the tribological properties of the coatings.Originality/value: The paper contributes to better understanding and recognition the structure of thin coatingsdeposited by PVD techniques. It should be stressed that the mechanical properties of the PVD coatings obtained inthis work are very encouraging and therefore their application for products manufactured at mass scale is possiblein all cases where reliable, very hard and abrasion resistant coatings, deposited onto brass substrate are needed.

  15. Thermoluminescence of Y2O3:Tb3+ thin films deposited by electron beam evaporation

    International Nuclear Information System (INIS)

    Most thermoluminescent materials are created using crystal growth techniques; however, it would be of great utility to identify those few thermoluminescent materials that can be deposited using simpler methods, for example to be compatible with the early portions of a silicon integrated circuit or microelectromechanical fabrication process. In this work, thin films of yttrium oxide with a terbium impurity (Y2O3:Tb) were deposited on silicon wafers by electron beam evaporation. The source for the Y2O3:Tb was made by combining Y2O3 and Tb4O7 powders. The approximate thicknesses of the deposited films were 350 nm. After deposition, the films were annealed at 1100 °C for 30 s to improve crystallinity. There is a strong correlation between the x-ray diffraction (XRD) peak intensity and the thermoluminescent glow curve intensity. The glow curve displays at least two peaks at 140 °C and 230 °C. The emission spectra was measured using successive runs with a monochromator set to a different wavelength for each run. There are two main emission peaks at 490 nm and 540 nm. The terbium impurity concentration of approximately 1 mol% was measured using Rutherford backscattering spectrometry (RBS). The Y2O3:Tb is sensitive to UV, x-ray, and gamma radiation. The luminescent intensity per unit mass of UV irradiated Y2O3:Tb was about 2 times that of x-ray irradiated TLD-100. -- Highlights: • Y2O3:Tb3+ thin film can be deposited using the common microfabrication technique of electron beam evaporation. • The Y2O3:Tb3+ requires an anneal of at least 900 °C to show thermoluminescence and 1100 °C anneal for the strongest thermoluminescent signal. • The Y2O3:Tb3+ will show a glow curve after being exposed to ionizing radiation from UV, x-ray, and gamma ray sources. • The luminescent intensity per unit mass of the UV irradiated Y2O3:Tb3+ is twice that of x-ray irradiated TLD-100(LiF:Ti, Mg)

  16. Ion-beam analysis of CuInSe2 solar cells deposited on polyimide foil.

    Science.gov (United States)

    Spemann, D; Lorenz, M; Butz, T; Otte, K

    2004-06-01

    CuInSe(2) (CIS) solar cells deposited on polyimide foil by the Solarion company in a web-coater-based process using sputter and evaporation techniques were investigated in the ion beam laboratory LIPSION of the University of Leipzig by means of Rutherford backscattering spectrometry (RBS) and particle-induced X-ray emission (PIXE) using high-energy broad ion beams and microbeams. From these measurements the composition of the absorber and the lateral homogeneity and film thicknesses of the individual layers could be determined on the basis of some reasonable assumptions. For the first time, quantitative depth profiling of the individual elements was performed by microPIXE measurements on a beveled section prepared by ion-beam etching of a CIS solar cell. Within the CIS absorber layer no significant concentration-depth gradients were found for Cu, In, and Se, in contrast with results from secondary neutral mass spectrometry (SNMS) depth profiling, which was applied to the same samples for comparison. Furthermore, both PIXE and SNMS showed the presence of a remarkable amount of Cd from the CdS buffer layer in the underlying absorber. PMID:15179537

  17. Properties of Cu film and Ti/Cu film on polyimide prepared by ion beam techniques

    International Nuclear Information System (INIS)

    Cu film and Ti/Cu film on polyimide substrate were prepared by ion implantation and ion beam assisted deposition (IBAD) techniques. Three-dimension white-light interfering profilometer was used to measure thickness of each film. The thickness of the Cu film and Ti/Cu film ranged between 490 nm and 640 nm. The depth profile, surface morphology, roughness, adhesion, nanohardness, and modulus of the Cu and Ti/Cu films were measured by scanning Auger nanoprobe (SAN), atomic force microscopy (AFM), and nanoindenter, respectively. The polyimide substrates irradiated with argon ions were analyzed by scanning electron microscopy (SEM) and AFM. The results suggested that both the Cu film and Ti/Cu film were of good adhesion with polyimide substrate, and ion beam techniques were suitable to prepare thin metal film on polyimide.

  18. Structure and interfacial analysis of nanoscale TiNi thin film prepared by biased target ion beam deposition

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Huilong; Hamilton, Reginald F., E-mail: rfhamilton@psu.edu; Horn, Mark W. [Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2015-07-15

    Ultrathin, 65 nm thick, TiNi alloy films were fabricated by cosputtering Ti and Ni targets using the recently developed biased target ion beam deposition technique. Preheating the substrate by exposure to a low energy ion source resulted in as-deposited films with a pure B2 atomic crystal structure containing no secondary crystal structures or precipitates. Continuous films were produced with a smooth surface and minimal substrate/film interfacial diffusion. The diffusion layer was a small ratio of film thickness, which is a prerequisite for the B2 phase to undergo the martensitic transformation in ultrathin films.

  19. Transport Properties of LCMO Granular Films Deposited by the Pulsed Electron Deposition Technique

    Institute of Scientific and Technical Information of China (English)

    CHEN Leiming; XU Bin; ZHANG Yan; CHEN Zhenping

    2011-01-01

    By finely controlling the deposition parameters in the pulsed electron deposition process,granular La2/3Ca1/3MnO3 (LCMO) film was grown on silicon substrates.The substrate temperature,ambient pressure in the deposition chamber and acceleration potential for the electron beam were all found to affect the grain size of the film,resulting in different morphologies of the samples.Transport properties of the obtained granular films,especially the magnetoresistance (MR),were studied.Prominent low-field MR was observed in all samples,indicating the forming of grain boundaries in the sample.The low-field MR show great sensitive to the morphology evolution,which reaches the highest value of about 40% for the sample with the grain size of about 250 nm.More interestingly,positive-MR (p-MR) was also detected above 300 K when low magnetic field applying,whereas it disappeared with higher magnetic field applied up to 1.5 and 2 Tesla.Instead of the spinpolarized tunneling process being commonly regarded as a responsible reason,lattice mismatch between LCMO film and silicon substrate appears to be the origin of the p-MR

  20. Ion beam analytical techniques in atmospheric aerosol studies

    International Nuclear Information System (INIS)

    An ion beam analytical facility has been developed for application to atmospheric aerosol samples. It combines Particle-Induced X-ray Emission (PIXE) and Particle Elastic Scattering Analysis (PESA). Elemental concentrations for elements heavier than silicon are determined with PIXE, with minimum detection limits of the order of 1 ng/cm2. Hydrogen, carbon, nitrogen and oxygen are determined with PESA. Minimum detection limits are 100, 15, 10 and 350 ng/cm2, respectively. Evaporative losses during analysis were investigated. The problem mainly applies to the light elements, such as elements present in organic compounds of relatively high saturation vapour pressure. The analytical facility, an external beam setup, allows a helium atmosphere to surround the sample. Quantitative analysis for compounds with saturation vapour pressure below about 10-5 torr (room temperature) is possible. A method for chemical speciation using multi-elemental ion beam techniques and thermography is presented; Ion Beam Thermography (IBT). Utilizing elemental thermal data and stoichiometry, chemical speciation is obtained. The influence of distant aerosol sources in southern Sweden was investigated using a three-station network. Multivariate statistical evaluation, based on SIMCA, revealed an elemental composition size dependence in the accumulation mode. The results indicate that transformation processes are more important than emission sources for the covariation of sulphur. A technique for the identification of outliers in a data set is presented, which is based on a three-step multivariate statistical evaluation. (author)

  1. Material properties of ion beam deposited oxides for the optoelectronic industry

    International Nuclear Information System (INIS)

    High quality, dense films of SiO2, Al2O3, Ta2O5, and TiO2 were deposited with an ion beam deposition system (IBD). IBD has significant advantages over other techniques in terms of directionality, stress control, repeatability, thermal stability, and film uniformity [J. J. Cuomo, J. M. E. Harper, C. R. Guarnieri, D. S. Yee, L. J. Atanasio, J. Angilello, C. T. Wu, and R. H. Hammond, J. Vac. Sci. Technol. 20, 349 (1982)]. To decrease the surface damage induced by ion bombardment, a multi-energy process was developed. This is especially important for laser facet coatings. The oxide films were optimized for the desired refractive index and zero absorption. Stress values of -0.2 to -0.5 GPa (compressive) and extremely good uniformity (2, all films remained in compressive stress after annealing. TiO2 turned tensile. With the variety of oxide materials developed, designing an anti-reflective or highly reflective stack, which satisfies requirements of stress, uniformity, deposition rate, and reflectance, becomes a matter of choosing the appropriate material set

  2. Indium-tin-oxide thin film deposited by a dual ion beam assisted e-beam evaporation system

    International Nuclear Information System (INIS)

    Indium-tin-oxide (ITO) thin films were deposited on polycarbonate (PC) substrates at low temperatures (<90 deg. C) by a dual ion beam assisted e-beam evaporation system, where one gun (gun 1) is facing ITO flux and the other gun (gun 2) is facing the substrate. In this experiment, effects of rf power and oxygen flow rate of ion gun 2 on the electrical and optical properties of depositing ITO thin films were investigated. At optimal deposition conditions, ITO thin films deposited on the PC substrates larger than 20 cmx20 cm showed the sheet resistance of less than 40 Ω/sq., the optical transmittance of above 90%, and the uniformity of about 5%

  3. Electrical performance of phase change memory cells with Ge3Sb2Te6 deposited by molecular beam epitaxy

    International Nuclear Information System (INIS)

    Here, we report on the electrical characterization of phase change memory cells containing a Ge3Sb2Te6 (GST) alloy grown in its crystalline form by Molecular Beam Epitaxy (MBE). It is found that the high temperature growth on the amorphous substrate results in a polycrystalline film exhibiting a rough surface with a grain size of approximately 80–150 nm. A detailed electrical characterization has been performed, including I-V characteristic curves, programming curves, set operation performance, crystallization activation at low temperature, and resistance drift, in order to determine the material related parameters. The results indicate very good alignment of the electrical parameters with the current state-of-the-art GST, deposited by physical vapor deposition. Such alignment enables a possible employment of the MBE deposition technique for chalcogenide materials in the phase change memory technology, thus leading to future studies of as-deposited crystalline chalcogenides as integrated in electrical vehicles

  4. Investigation of failure mechanism of thermal barrier coatings (TBCs) deposited by EB-PVD technique

    International Nuclear Information System (INIS)

    Failure mechanism of thermal barrier coatings (TBCs) prepared by electron beam physical vapor deposition (EB-PVD) technique owing to formation of micro cracks was investigated. The TBCs were deposited on the Ni-based super alloy IN-100 and the micro cracks were observed within the top ceramic coat of thermally cycled TBCs at 1050°C. It was observed that these cracks propagate in the ceramic coat in the direction normal to interface while no cracks were observed in the bond coat. SEM/EDS studies revealed that some non-uniform oxides were formed on the interface between ceramic top and metallic bond coat just below the cracks. Study proposed that the cracks were initiated due to stress owing to big difference in Pilling-Bed worth ratio of non-uniform oxides as well as thermal stress, which caused the formation of cracks in top ceramic coat leading to failure of TBCs

  5. Friction and Wear of Ion-Beam-Deposited Diamondlike Carbon on Chemical-Vapor-Deposited, Fine-Grain Diamond

    Science.gov (United States)

    Miyoshi, Kazuhisa; Wu, Richard L. C.; Lanter, William C.

    1996-01-01

    Friction and wear behavior of ion-beam-deposited diamondlike carbon (DLC) films coated on chemical-vapor-deposited (CVD), fine-grain diamond coatings were examined in ultrahigh vacuum, dry nitrogen, and humid air environments. The DLC films were produced by the direct impact of an ion beam (composed of a 3:17 mixture of Ar and CH4) at ion energies of 1500 and 700 eV and an RF power of 99 W. Sliding friction experiments were conducted with hemispherical CVD diamond pins sliding on four different carbon-base coating systems: DLC films on CVD diamond; DLC films on silicon; as-deposited, fine-grain CVD diamond; and carbon-ion-implanted, fine-grain CVD diamond on silicon. Results indicate that in ultrahigh vacuum the ion-beam-deposited DLC films on fine-grain CVD diamond (similar to the ion-implanted CVD diamond) greatly decrease both the friction and wear of fine-grain CVD diamond films and provide solid lubrication. In dry nitrogen and in humid air, ion-beam-deposited DLC films on fine-grain CVD diamond films also had a low steady-state coefficient of friction and a low wear rate. These tribological performance benefits, coupled with a wider range of coating thicknesses, led to longer endurance life and improved wear resistance for the DLC deposited on fine-grain CVD diamond in comparison to the ion-implanted diamond films. Thus, DLC deposited on fine-grain CVD diamond films can be an effective wear-resistant, lubricating coating regardless of environment.

  6. Total body irradiation (sweeping beam technique) prior bone marrow transplantation

    International Nuclear Information System (INIS)

    There are given the principle and basic informations about Sweeping beam technique with gantry rotation on LINAC ORION 6. The whole process of treatment is presented here: CT - determination of reference points and reference slices (AP, PA) Simulator - localization of lung shielding (AP, PA) Linac - determination of some physical parameters - simulation of radiation technique Treatment planning - calculation of treatment time and number of sweeps - determination of lung shielding Model laboratory - preparation of lung shielding blocks - blocks position and fixation Radiation therapy - verification of shielding blocks - patient irradiation (AP, PA) Dosimetry in-vivo - determination of patient's doses At the end the presentation of physical results with group of 55 patients is reported

  7. Characterisation of molecular thin films grown by organic molecular beam deposition

    CERN Document Server

    Bayliss, S M

    2000-01-01

    This work concerns the growth and characterisation of molecular thin films in an ultra high vacuum regime by organic molecular beam deposition (OMBD). Films of three different molecular materials are grown, namely free base phthalocyanine (H sub 2 Pc), perylene 3,4,9,10-tetracarboxylic dianhydride (PTCDA) and aluminium tris-8-hydroxyquinoline (Alq sub 3). The relationship between the growth parameters such as film thickness, growth rate, and substrate temperature during and after growth, and the structural, optical and morphological properties of the film are investigated. These investigations are carried out using various ex-situ techniques. X-ray diffraction, Raman spectroscopy and electronic absorption spectroscopy are used to probe the bulk film characteristics, whilst Nomarski microscopy and atomic force microscopy are used to study the surface morphology. Three different levels of influence of the growth parameters on the film properties are observed. In the case of H sub 2 Pc, two crystal phases are fo...

  8. Nanostructures and sensing properties of ZnO prepared using normal and oblique angle deposition techniques

    Energy Technology Data Exchange (ETDEWEB)

    Chu Jin; Peng Xiaoyan; Sajjad, M. [Department of Physics, University of Puerto Rico, San Juan, 00936 (Puerto Rico); Yang Boqian [Department of Physics, University of Massachusetts Amherst, MA 01003 (United States); Feng, Peter X., E-mail: p.feng@upr.edu [Department of Physics, University of Puerto Rico, San Juan, 00936 (Puerto Rico)

    2012-02-29

    Nanostructured zinc oxide (ZnO) for gas sensing application has been prepared by using normal and oblique angle sputtering deposition techniques under different substrate temperatures. Oblique angle plasma beam deposition is demonstrated effectively growing large-area uniformly aligned and inclined ZnO nanorod arrays on catalyst-free silicon substrate due to a self-shadowing mechanism, whereas normal radio frequency sputtering deposition yields nanoparticles as island growth mode. Furthermore, the density of the nanorod arrays is dependent on the incident angle of ZnO plasma beam. With an increase of the incident flux angle, large inter spacing was induced, resulting in sparser nanorod arrays. The nanorod arrays grown with an incident angle of 70 Degree-Sign have an average diameter of {approx} 150-300 nm and length of {approx} 700-750 nm. The experimental data from characterization of the samples indicates that the obtained samples at different substrate temperatures and incident angles have wurtzite structure with a c-axis orientation. Sensing characterization reveals that the nanorod-based sensor shows higher sensitivity, faster response and recovery time, as well as better reproducibility than that of nanoparticle-based gas sensor to 100 ppm hydrogen and methane at low operating temperature below 150 Degree-Sign C due to the porosity and large grain boundaries of the nanorod arrays. It demonstrates that oblique angle of sputtering deposition is a simple, inexpensive synthesis process to get high-porosity nanostructures and as a result, improves the sensing properties of fabricated ZnO sensors, which permits us to obtain sensors with high sensitivity, low operating temperature and stability. - Highlights: Black-Right-Pointing-Pointer Surface morphology depends on the deposition angle during sputtering. Black-Right-Pointing-Pointer High quality crystalline ZnO by radio frequency sputtering obtained at 350 Degree-Sign C. Black-Right-Pointing-Pointer ZnO nanorod

  9. Enhancement of neutral beam deposition in hydrogen discharge using carbon pellet injection in LHD

    International Nuclear Information System (INIS)

    The central ion temperature in the large helical device (LHD), as measured by charge-exchange recombination spectroscopy, has been improved to a record 5.6 keV by combining 21 MW of neutral beam heating with the injection of a carbon pellet. The intensity of the neutral beam emission of the hydrogen Balmer line (Hα: n=3 → 2) was observed to weaken along the beam injection axis following the carbon pellet injection due to the increased beam attenuation. The beam-emission intensity was reconstructed by calculating the density distribution, and the beam-stopping coefficients, along a beam injection axis and was found to fit well to the measured beam-emission for a mixed hydrogen and carbon target plasma. The dynamics of the neutral beam deposition power and the carbon fraction were estimated from the beam-emission measurements using data from ADAS. We conclude that the beam deposition power in a carbon pellet discharge is enhanced over that of a pure hydrogen discharge. (author)

  10. Lateral resolution in focused electron beam-induced deposition: scaling laws for pulsed and static exposure

    International Nuclear Information System (INIS)

    In this work, we review the single-adsorbate time-dependent continuum model for focused electron beam-induced deposition (FEBID). The differential equation for the adsorption rate will be expressed by dimensionless parameters describing the contributions of adsorption, desorption, dissociation, and the surface diffusion of the precursor adsorbates. The contributions are individually presented in order to elucidate their influence during variations in the electron beam exposure time. The findings are condensed into three new scaling laws for pulsed exposure FEBID (or FEB-induced etching) relating the lateral resolution of deposits or etch pits to surface diffusion and electron beam exposure dwell time for a given adsorbate depletion state. (orig.)

  11. Microstructure and properties of silver films obtained using ion beam composite deposition

    International Nuclear Information System (INIS)

    Using ion beam composite deposition method Magnetron sputtering deposition, soft metal solid lubricant of Ag film was grown on 9Crl8 steel substrate. The microstructures and friction properties were measured by means of the hundred cell knife scratch method, MS-T3000 multi-meter friction and wear testing and scanning electron microscopy. The results showed that compared with the magnetron sputtering method, a transition layer bonded with chemical metallurgy and mechanical engagement is formed after ion beam composite deposition. The transition layer can be attributed to the strong adhesion between the film and the substrate. (authors)

  12. Ion beam analysis techniques applied to large scale pollution studies

    International Nuclear Information System (INIS)

    Ion Beam Analysis (IBA) techniques are ideally suited to analyse the thousands of filter papers a year that may originate from a large scale aerosol sampling network. They are fast multi-elemental and, for the most part, non-destructive so other analytical methods such as neutron activation and ion chromatography can be performed afterwards. ANSTO in collaboration with the NSW EPA, Pacific Power and the Universities of NSW and Macquarie has established a large area fine aerosol sampling network covering nearly 80,000 square kilometres of NSW with 25 fine particle samplers. This network known as ASP was funded by the Energy Research and Development Corporation (ERDC) and commenced sampling on 1 July 1991. The cyclone sampler at each site has a 2.5 μm particle diameter cut off and runs for 24 hours every Sunday and Wednesday using one Gillman 25mm diameter stretched Teflon filter for each day. These filters are ideal targets for ion beam analysis work. Currently ANSTO receives 300 filters per month from this network for analysis using its accelerator based ion beam techniques on the 3 MV Van de Graaff accelerator. One week a month of accelerator time is dedicated to this analysis. Four simultaneous accelerator based IBA techniques are used at ANSTO, to analyse for the following 24 elements: H, C, N, O, F, Na, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Ni, Co, Zn, Br and Pb. The IBA techniques were proved invaluable in identifying sources of fine particles and their spatial and seasonal variations accross the large area sampled by the ASP network. 3 figs

  13. Ion beam analysis techniques applied to large scale pollution studies

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, D.D.; Bailey, G.; Martin, J.; Garton, D.; Noorman, H.; Stelcer, E.; Johnson, P. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1993-12-31

    Ion Beam Analysis (IBA) techniques are ideally suited to analyse the thousands of filter papers a year that may originate from a large scale aerosol sampling network. They are fast multi-elemental and, for the most part, non-destructive so other analytical methods such as neutron activation and ion chromatography can be performed afterwards. ANSTO in collaboration with the NSW EPA, Pacific Power and the Universities of NSW and Macquarie has established a large area fine aerosol sampling network covering nearly 80,000 square kilometres of NSW with 25 fine particle samplers. This network known as ASP was funded by the Energy Research and Development Corporation (ERDC) and commenced sampling on 1 July 1991. The cyclone sampler at each site has a 2.5 {mu}m particle diameter cut off and runs for 24 hours every Sunday and Wednesday using one Gillman 25mm diameter stretched Teflon filter for each day. These filters are ideal targets for ion beam analysis work. Currently ANSTO receives 300 filters per month from this network for analysis using its accelerator based ion beam techniques on the 3 MV Van de Graaff accelerator. One week a month of accelerator time is dedicated to this analysis. Four simultaneous accelerator based IBA techniques are used at ANSTO, to analyse for the following 24 elements: H, C, N, O, F, Na, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Ni, Co, Zn, Br and Pb. The IBA techniques were proved invaluable in identifying sources of fine particles and their spatial and seasonal variations accross the large area sampled by the ASP network. 3 figs.

  14. Introduction to focused ion beams instrumentation, theory, techniques and practice

    CERN Document Server

    Giannuzzi, Lucille A

    2005-01-01

    The focused ion beam (FIB) instrument has experienced an intensive period of maturation since its inception. Numerous new techniques and applications have been brought to fruition, and over the past few years, the FIB has gained acceptance as more than just an expensive sample preparation tool. It has taken its place among the suite of other instruments commonly available in analytical and forensic laboratories, universities, geological, medical and biological research institutions, and manufacturing plants. Although the utility of the FIB is not limited to the preparation of specimens for subsequent analysis by other analytical techniques, it has revolutionized the area of TEM specimen preparation. The FIB has also been used to prepare samples for numerous other analytical techniques, and offers a wide range of other capabilities. While the mainstream of FIB usage remains within the semiconductor industry, FIB usage has expanded to applications in metallurgy, ceramics, composites, polymers, geology, art, bio...

  15. External beam radiotherapy for retinoblastoma: Pt. 1: Whole eye technique

    International Nuclear Information System (INIS)

    A retrospective analysis has been performed of the results of external beam radiotherapy for retinoblastoma using a whole eye technique. Local tumour control has been assessed in a consecutive series of 175 eyes in 142 children all of whom received external beam radiotherapy as the primary treatment for retinoblastoma. Follow up ranged from 2 to 17 years (median 9 years). Tumour control rates have been analysed with respect to the Reese Ellsworth classification and the series includes eyes in groups I to V. Focal salvage therapy was given for persistent, recurrent, or new tumours after radiotherapy. Following whole eye radiotherapy alone, the overall ocular cure rate was 57%, though with salvage therapy 80% of eyes could be preserved. (author)

  16. HfO2 as gate dielectric on Ge: Interfaces and deposition techniques

    International Nuclear Information System (INIS)

    To fabricate MOS gate stacks on Ge, one can choose from a multitude of metal oxides as dielectric material which can be deposited by many chemical or physical vapor deposition techniques. As a few typical examples, we will discuss here the results from atomic layer deposition (ALD), metal organic CVD (MOCVD) and molecular beam deposition (MBD) using HfO2/Ge as materials model system. It appears that a completely interface layer free HfO2/Ge combination can be made in MBD, but this results in very bad capacitors. The same bad result we find if HfGe y (Hf germanides) are formed like in the case of MOCVD on HF-dipped Ge. A GeO x interfacial layer appears to be indispensable (if no other passivating materials are applied), but the composition of this interfacial layer (as determined by XPS, TOFSIMS and MEIS) is determining for the C/V quality. On the other hand, the presence of Ge in the HfO2 layer is not the most important factor that can be responsible for poor C/V, although it can still induce bumps in C/V curves, especially in the form of germanates (Hf-O-Ge). We find that most of these interfacial GeO x layers are in fact sub-oxides, and that this could be (part of) the explanation for the high interfacial state densities. In conclusion, we find that the Ge surface preparation is determining for the gate stack quality, but it needs to be adapted to the specific deposition technique

  17. Raman spectroscopic studies of thin film carbon nanostructures deposited using electro deposition technique

    Science.gov (United States)

    Dayal, Saurabh; Sasi, Arshali; Jhariya, Sapna; Sasikumar, C.

    2016-05-01

    In the present work our focus is to synthesize carbon nanostructures (CNS) by electro deposition technique without using any surface pretreatment or catalyst preparation before CNS formation. The process were carried out at significantly low voltage and at low temperature as reported elsewhere. Further the samples were characterized using different characterization tools such as SEM and Raman spectroscopy. The SEM results showed the fibres or tubular like morphology. Raman spectra shows strong finger print at 1600 cm-1 (G peak), 1350 cm-1 (D peak) along with the radial breathing mode (RBM) between 150cm-1 to 300 cm-1. This confirms the formation of tubular carbon nanostructures.

  18. Beam-induced energy deposition issues in the Very Large Hadron Collider

    CERN Document Server

    Mokhov, N V; Foster, G W

    2001-01-01

    Energy deposition issues are extremely important in the Very Large Hadron Collider (VLHC) with huge energy stored in its 20 TeV (Stage-1) and 87.5 TeV (Stage-2) beams. The status of the VLHC design on these topics, and possible solutions of the problems are discussed. Protective measures are determined based on the operational and accidental beam loss limits for the prompt radiation dose at the surface, residual radiation dose, ground water activation, accelerator components radiation damage and quench stability. The beam abort and beam collimation systems are designed to protect accelerator from accidental and operational beam losses, IP region quadrupoles from irradiation by the products of beam-beam collisions, and to reduce the accelerator-induced backgrounds in the detectors. (7 refs).

  19. Corrosion behavior of copper thin films deposited by EB-PVD technique on thermally grown silicon dioxide and glass in hydrochloric acid media

    International Nuclear Information System (INIS)

    Copper thin films were deposited on oxidized single crystal silicon and glass surfaces, at 70 deg. C and 150 deg. C substrate temperature using Electron Beam-Physical Vapor Deposition technique. The morphology and crystal orientation of the deposited film were investigated by SEM and XRD, respectively. Corrosion behavior of these films in hydrochloric acid was studied by potentiodynamic polarization method. Results showed that the corrosion resistance of CG 70 (deposit on glass at 70 deg. C substrate temperature) was higher than all deposits and than copper sheet because of its higher ability to form passive layer.

  20. Structural, electrical and optical properties of copper selenide thin films deposited by chemical bath deposition technique

    International Nuclear Information System (INIS)

    A low cost chemical bath deposition (CBD) technique has been used for the preparation of Cu2-xSe thin films on glass substrates. Structural, electrical and optical properties of these films were investigated. X-ray diffraction (XRD) study of the Cu2-xSe films annealed at 523K suggests a cubic structure with a lattice constant of 5.697A. Chemical composition was investigated by X-ray photoelectron spectroscopy (XPS). It reveals that absorbed oxygen in the film decreases remarkably on annealing above 423K. The Cu/Se ratio was observed to be the same in as-deposited and annealed films. Both as- deposited and annealed films show very low resistivity in the range of (0.04- 0.15) x 10-5 Ω-m. Transmittance and Reflectance were found in the range of 5-50% and 2-20% respectively. Optical absorption of the films results from free carrier absorption in the near infrared region with absorption coefficient of ∼108 m-1. The band gap for direct transition, Eg.dir varies in the range of 2.0-2.3eV and that for indirect transition Eg.indir is in the range of 1.25-1.5eV.1. (author)

  1. Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition

    Directory of Open Access Journals (Sweden)

    Brett B. Lewis

    2015-04-01

    Full Text Available Platinum–carbon nanostructures deposited via electron beam induced deposition from MeCpPt(IVMe3 are purified during a post-deposition electron exposure treatment in a localized oxygen ambient at room temperature. Time-dependent studies demonstrate that the process occurs from the top–down. Electron beam energy and current studies demonstrate that the process is controlled by a confluence of the electron energy loss and oxygen concentration. Furthermore, the experimental results are modeled as a 2nd order reaction which is dependent on both the electron energy loss density and the oxygen concentration. In addition to purification, the post-deposition electron stimulated oxygen purification process enhances the resolution of the EBID process due to the isotropic carbon removal from the as-deposited materials which produces high-fidelity shape retention.

  2. Structural properties of thermoelectric CoSb3 skutterudite thin films prepared by molecular beam deposition

    International Nuclear Information System (INIS)

    Highlights: • Different methods were used to deposit Co–Sb thin film by molecular beam deposition. • The phase formation is strongly dependent on the Sb content of the film. • The fabrication of high-quality single phase skutterudite thin films could be shown. • The grain size of the films is very sensitive to the used deposition parameters. • It was shown, that large deposition rates support the formation of parasitic phases. - Abstract: The research field of thermoelectricity was renewed by the progress made in nanostructuring approaches and by the investigation of new material groups as skutterudites, whose most promising representative is CoSb3. In this work Co–Sb thin films with a thickness of 30 nm were deposited by molecular beam deposition at different substrate temperatures as well as on non-heated substrates followed by a post-annealing step. An extended investigation of the phase formation in dependence of deposition method and parameters, film composition, and post-treatment is given. The presented results provide different routes to achieve high quality single phase films. It was also demonstrated that the grain size of the CoSb3 thin films is very sensitive to the used deposition method and especially on the substrate temperature during deposition. A controllable grain size by changing the deposition parameters could be a key feature for the optimization of the thermoelectric properties, since especially the thermal conductivity should strongly depend on the grain size due to enhanced grain boundary scattering of phonons

  3. Poly(methyl methacrylate) Composites with Size-selected Silver Nanoparticles Fabricated Using Cluster Beam Technique

    DEFF Research Database (Denmark)

    Hanif, Muhammad; Juluri, Raghavendra R.; Chirumamilla, Manohar;

    2016-01-01

    based on cluster beam technique allowing the formation of monocrystalline size-selected silver nanoparticles with a +/- 5-7% precision of diameter and controllable embedment into poly (methyl methacrylate). It is shown that the soft-landed silver clusters preserve almost spherical shape with a slight......An embedment of metal nanoparticles of well-defined sizes in thin polymer films is of significant interest for a number of practical applications, in particular, for preparing materials with tunable plasmonic properties. In this article, we present a fabrication route for metal-polymer composites...... tendency to flattening upon impact. By controlling the polymer hardness (from viscous to soft state) prior the cluster deposition and annealing conditions after the deposition the degree of immersion of the nanoparticles into polymer can be tuned, thus, making it possible to create composites with either...

  4. VOC removal by microwave, electron beam and catalyst technique

    International Nuclear Information System (INIS)

    A hybrid technique, developed for VOCs removal using microwave (MW) treatment, electron beam (EB) irradiation and catalyst method, is presented. Two hybrid laboratory installations, developed for the study of air pollution control by combined EB irradiation, MW irradiation and catalyst, are described. Air loaded with toluene was treated at different MW power levels, water content, flow rates, and different irradiation modes, separately and combined with MW and EB. Also, simultaneous EB and MW irradiation method was applied to SO2 and NOx removal. Real synergy effects between EB induced NTP, MW induced NTP and catalysis can be observed

  5. Microstructural Characterization of Au-In Thin Film Deposited by Electron Beam Evaporation

    International Nuclear Information System (INIS)

    The microstructure and phase formation of Au-In thin film deposited by e-beam evaporation technique has been studied. Single crystals of rock salt were used as the substrates. The chamber pressure during deposition was about 2.5 x 10-5 torr and substrate temperature was 35 degree Celsius. Three types of samples were prepared namely Au, In and Au-In thin films. Microstructure and chemical composition of these thin films were characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectrometer (XPS) respectively. TEM micrograph reveals island structures for both Au and In thin film on the rock salt substrate, with the In island size distribution is about 9-30 nm compared to Au island in the range of 3-10 nm. The growth of islands instead of smooth film indicates that Au and In thin films follow the Volmer-Weber growth mode. However, island structures were not present on Au-In thin films which most probably follow the Frank van de Merwe growth mode. XPS analysis indicates intermetallic compound was not present in the Au-In thin film suggesting that diffusion process in the interface of Au and In films is minimal. (author)

  6. Beam induced deposition of platinum using a helium ion microscope

    NARCIS (Netherlands)

    Sanford, C.A.; Stern, L.; Barriss, L.; Farkas, L.; DiManna, M.; Mello, R.; Maas, D.J.; Alkemade, P.F.A.

    2009-01-01

    Helium ion microscopy is now a demonstrated practical technology that possesses the resolution and beam currents necessary to perform nanofabrication tasks, such as circuit edit applications. Due to helium’s electrical properties and sample interaction characteristics relative to gallium, it is like

  7. Beam induced deposition of platinum using a helium ion microscope

    NARCIS (Netherlands)

    Sanford, C.A.; Stern, L.; Barriss, L.; Farkas, L.; DiManna, M.; Mello, R.; Maas, D.J.; Alkemade, P.F.A.

    2009-01-01

    Helium ion microscopy is now a demonstrated practical technology that possesses the resolution and beam currents necessary to perform nanofabrication tasks, such as circuit edit applications. Due to helium's electrical properties and sample interaction characteristics relative to gallium, it is like

  8. Energy deposition, heat flow, and rapid solidification during laser and electron beam irradiation of materials

    International Nuclear Information System (INIS)

    The fundamentals of energy deposition, heat flow, and rapid solidification during energy deposition from lasers and electron beams is reviewed. Emphasis is placed on the deposition of energy from pulsed sources (10 to 100 ns pulse duration time) in order to achieve high heating and cooling rates (108 to 10100C/s) in the near surface region. The response of both metals and semiconductors to pulsed energy deposition is considered. Guidelines are presented for the choice of energy source, wavelength, and pulse duration time

  9. Plasmonic Gold Helices for the visible range fabricated by oxygen plasma purification of electron beam induced deposits

    CERN Document Server

    Haverkamp, Caspar; Jäckle, Sara; Manzoni, Anna; Christiansen, Silke

    2016-01-01

    Electron beam induced deposition (EBID) currently provides the only direct writing technique for truly three-dimensional nanostructures with geometrical features below 50 nm. Unfortunately, the depositions from metal-organic precursors suffer from a substantial carbon content. This hinders many applications, especially in plasmonics where the metallic nature of the geometric surfaces is mandatory. To overcome this problem a post-deposition treatment with oxygen plasma at room temperature was investigated for the purification of gold containing EBID structures. Upon plasma treatment, the structures experience a shrinkage in diameter of about 18 nm but entirely keep their initial shape. The proposed purification step results in a core-shell structure with the core consisting of mainly unaffected EBID material and a gold shell of about 20 nm in thickness. These purified structures are plasmonically active in the visible wavelength range as shown by dark field optical microscopy on helical nanostructures. Most no...

  10. Diffusion and Interface Reaction of Cu/Si (100) Films Prepared by Cluster Beam Deposition

    International Nuclear Information System (INIS)

    Cu thin films are deposited on Si (100) substrates by neutral cluster beams and ionized cluster beams. The atomic diffusion and interface reaction between the Cu films and the Si substrates of as-deposited and annealed at different temperatures (230°C, 450°C, 500°C and 600°C) are investigated by Rutherford backscattering spectrometry (RBS) and x-ray diffraction (XRD). Some significant results are obtained on the following aspects: (1) For the Cu/Si(100) samples prepared by neutral cluster beams and ionized cluster beams at Va = 0kV, atomic diffusion phenomena are observed clearly in the as-deposited samples. With the increase of annealing temperature, the interdiffusion becomes more apparent. However, the diffusion intensities of the RBS spectra of the Cu/Si(100) films using neutral cluster beams are always higher than that of the Cu/Si(100) films using ionized cluster beams at Va=0kV in the as-deposited and samples annealed at the same temperature. The compound of Cu3Si is observed in the as-deposited samples. (2) For the Cu/Si(100) samples prepared by ionized cluster beams at Va=1, 3, 5kV, atomic diffusion phenomena are observed in the as-deposited samples at Va=1, 5kV. For the samples prepared at Va = 3kV, the interdiffusion phenomenon is observed until 500°C annealing temperature. The reason for the difference is discussed. (atomic and molecular physics)

  11. New approaches for investigating paintings by ion beam techniques

    International Nuclear Information System (INIS)

    Up to now, among the IBA techniques, only PIXE has been used for analyzing paintings. However, quantitative PIXE analysis is sometimes difficult to interpret due to the layered structure, the presence of varnish and organic binder and, in some cases, discoloration of the pigments has been observed due to the interaction of the ion beam with the compounds. In order to improve the characterization of paintings, we propose some alternative experimental procedures. First of all, backscattering spectrometry (BS) and PIXE are simultaneously combined in order to collect complementary information such as layer thickness and organic compound quantification. The simultaneous PIXE and BS experiments also have the advantage of being able to analyze the same area in one experiment. This combination, implemented with an external beam, was directly applied on paintings and on painting cross-sections for the study of Italian Renaissance masterpieces. We have obtained valuable results not only on the pigment itself but also, for the first time, on the binder to pigment proportion which is not well documented in the ancient recipes. Moreover, in order to restrain beam damages due to the ion stopping power, we propose to analyze very thin painting cross-sections by a combination of PIXE-RBS and Scanning Transmission Ion Microscopy (STIM).

  12. Some applications of ion beam techniques in earth science research

    International Nuclear Information System (INIS)

    Ion beam analysis (IBA) techniques at GNS are used to (1) analyse for elemental compositions of rock powders and minerals including coal, (2) determine fine-scale elemental distributions in glass, individual minerals and whole rocks using imaging, line-scanning or point analyses and (3) probe compositions of buried structures in polished rock sections such as fluid and melt inclusions including daughter minerals in fluid inclusions. Apart from these, IBA techniques are also used (1) for standard-independent hydrogen detection and profiling at ppm levels (e.g. elastic recoil detection analysis or ERDA) and elemental depth profiling (Rutherford backscattering or RBS), (2) to probe lattice residence of major and minor trace elements and (3) to map zonation of certain ions, such as REE, in minerals using ionoluminescence (IL) or a combination of cathodoluminescence and PIXE. (author). 82 refs., 9 figs

  13. Some applications of ion beam techniques in earth science research

    International Nuclear Information System (INIS)

    Ion beam analysis (IBA) techniques at GNS are used to (1) analyse for elemental compositions of rock powders and minerals including coal, (2) determine fine-scale elemental distributions in glass, individual minerals and whole rocks using imaging, line-scanning or point analyses and (3) probe compositions of buried structures in polished rock sections such as fluid and melt inclusions including daughter minerals in fluid inclusions. Apart from these, IBA techniques are also used (1) for standard-independent hydrogen detection and profiling at ppm levels (e.g. elastic recoil detection analysis or ERDA) and elemental depth profiling (Rutherford backscattering or RBS), (2) to probe lattice residence of major and minor trace elements and (3) to map zonation of certain ions, such as REE, in minerals using ionoluminescence (IL) or a combination of cathodoluminescence and PIXE. (author). 84 refs., 9 figs

  14. Neutral atom beam technique enhances bioactivity of PEEK

    Energy Technology Data Exchange (ETDEWEB)

    Khoury, Joseph, E-mail: jkhoury@exogenesis.us [Exogenesis Corporation, Billerica, MA 01821 (United States); Kirkpatrick, Sean R.; Maxwell, Melissa; Cherian, Raymond E.; Kirkpatrick, Allen; Svrluga, Richard C. [Exogenesis Corporation, Billerica, MA 01821 (United States)

    2013-07-15

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants.

  15. Neutral atom beam technique enhances bioactivity of PEEK

    International Nuclear Information System (INIS)

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants

  16. Neutral atom beam technique enhances bioactivity of PEEK

    Science.gov (United States)

    Khoury, Joseph; Kirkpatrick, Sean R.; Maxwell, Melissa; Cherian, Raymond E.; Kirkpatrick, Allen; Svrluga, Richard C.

    2013-07-01

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants.

  17. Strontium-substituted hydroxyapatite coatings deposited via a co-deposition sputter technique

    International Nuclear Information System (INIS)

    The bioactivity of hydroxyapatite (HA) coatings can be modified by the addition of different ions, such as silicon (Si), lithium (Li), magnesium (Mg), zinc (Zn) or strontium (Sr) into the HA lattice. Of the ions listed here, strontium substituted hydroxyapatite (SrHA) coatings have received a lot of interest recently as Sr has been shown to promote osteoblast proliferation and differentiation, and reduce osteoclast activity. In this study, SrHA coatings were deposited onto titanium substrates using radio frequency (RF) magnetron co-sputtering (and compared to those surfaces deposited from HA alone). FTIR, XPS, XRD, and SEM techniques were used to analyse the different coatings produced, whereby different combinations of pure HA and 13% Sr-substituted HA targets were investigated. The results highlight that Sr could be successfully incorporated into the HA lattice to form SrHA coatings. It was observed that as the number of SrHA sputtering targets in the study were increased (increasing Sr content), the deposition rate decreased. It was also shown that as the Sr content of the coatings increased, so did the degree of preferred 002 orientation of the coating (along with obvious changes in the surface morphology). This study has shown that RF magnetron sputtering (specifically co-sputtering), offers an appropriate methodology to control the surface properties of Sr-substituted HA, such as the crystallinity, stoichiometry, phase purity and surface morphology. - Graphical abstract: (a) SEM image shows homogeneous hydroxyapatite (HA) micro-crystallites (< 300 nm in diameter) for a HA sputter deposited coating. (b) SEM image showing more heterogeneous surface features on a Sr-substituted HA (SrHA) coating. The XPS spectra in (a) confirms the presence of a HA coating as opposed to (b) XPS spectra for a SrHA coating. - Highlights: • First attempt to sputter strontium substituted hydroxyapatite thin films using RF magnetron co-deposition • Strontium content of coatings

  18. Structural and growth aspects of electron beam physical vapor deposited NiO-CeO{sub 2} nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    Kuanr, Sushil Kumar; K, Suresh Babu, E-mail: sureshbabu.nst@pondiuni.edu.in [Centre for Nanoscience and Technology, Madanjeet School of Green Energy Technologies, Pondicherry University, Puducherry 605 014 (India)

    2016-03-15

    Deposition of composite materials as thin film by electron beam physical vapor deposition technique (EB-PVD) still remains as a challenge. Here, the authors report the deposition of NiO-CeO{sub 2} (30/70 wt. %) composites on quartz substrate by EB-PVD. Two NiO-CeO{sub 2} nanocomposite targets—one as green compact and the other after sintering at 1250 °C—were used for the deposition. Though the targets varied with respect to physical properties such as crystallite size (11–45 nm) and relative density (44% and 96%), the resultant thin films exhibited a mean crystallite size in the range of 20–25 nm underlining the role of physical nature of deposition. In spite of the crystalline nature of the targets and similar elemental concentration, a transformation from amorphous to crystalline structure was observed in thin films on using sintered target. Postannealing of the as deposited film at 800 °C resulted in a polycrystalline structure consisting of CeO{sub 2} and NiO. Deposition using pure CeO{sub 2} or NiO as target resulted in the preferential orientation toward (111) and (200) planes, respectively, showing the influence of adatoms on the evaporation and growth process of NiO-CeO{sub 2} composite. The results demonstrate the influence of electron beam gun power on the adatom energy for the growth process of composite oxide thin films.

  19. Megaelectron volt ion beam-induced epitaxy of deposited silicon and germanium-silicon alloys on (100) silicon substrates

    International Nuclear Information System (INIS)

    Solid phase heteroepitaxial crystallization of GexSi1-x/(100) Si was induced by MeV ion bombardment while heating the substrate at low temperatures. Rutherford Backscatter Spectrometry (RBS), Ion Channeling, Secondary Ion Mass Spectroscopy (SIMS) and transmission electron microscopy (TEM) techniques were used to investigate the kinetics of the reordering process as well as characterize the strain in the resultant epitaxial layer. The epitaxial recrystallization of amorphous silicon and silicon-germanium layers on (100)silicon, deposited under medium (10-7 torr) vacuum conditions, was induced by 2.5 MeV Ar beam irradiation in the low temperature range of 200-400C. The regrowth follows an Arrhenius dependence with temperature and activation energies of ∼0.3 eV were determined for the regrowth of deposited Si and a Ge38Si62 alloy. Ion beam induced heteroepitaxy was found to be sensitive to interfacial contaminants. In addition, the resultant crystalline quality for Ge-rich alloys was poor after irradiation. Ion beam induced heteroepitaxy of MBE-deposited GexSi1-x/(100) Si, deposited under high vacuum conditions after strict interfacial preparation, resulted in layer-by-layer reordering for alloys up to 65 at. % Ge. Coherently strained epilayers were reported for ion beam annealed GeSi alloys with germanium concentration less than 15 at. %. The pseudomorphic epilayers were characterized by planar and axial channeling to measure the tetragonal distortion in the strained overlayers. Strained films, produced by MeV Ar bombardment while heating the substrate at temperatures as low as 300C, were observed to relax following extended furnace anneals at temperatures of 800-900C. Such results offer the possibility of extending defect-free growth of metastable strained layers to other lattice mismatched systems

  20. On the magnetic properties of iron nanostructures fabricated via focused electron beam induced deposition and autocatalytic growth processes.

    Science.gov (United States)

    Tu, F; Drost, M; Vollnhals, F; Späth, A; Carrasco, E; Fink, R H; Marbach, H

    2016-09-01

    We employ Electron beam induced deposition (EBID) in combination with autocatalytic growth (AG) processes to fabricate magnetic nanostructures with controllable shapes and thicknesses. Following this route, different Fe deposits were prepared on silicon nitride membranes under ultra-high vacuum conditions and studied by scanning electron microscopy (SEM) and scanning transmission x-ray microspectroscopy (STXM). The originally deposited Fe nanostructures are composed of pure iron, especially when fabricated via autocatalytic growth processes. Quantitative near-edge x-ray absorption fine structure (NEXAFS) spectroscopy was employed to derive information on the thickness dependent composition. X-ray magnetic circular dichroism (XMCD) in STXM was used to derive the magnetic properties of the EBID prepared structures. STXM and XMCD analysis evinces the existence of a thin iron oxide layer at the deposit-vacuum interface, which is formed during exposure to ambient conditions. We were able to extract magnetic hysteresis loops for individual deposits from XMCD micrographs with varying external magnetic field. Within the investigated thickness range (2-16 nm), the magnetic coercivity, as evaluated from the width of the hysteresis loops, increases with deposit thickness and reaches a maximum value of ∼160 Oe at around 10 nm. In summary, we present a viable technique to fabricate ferromagnetic nanostructures in a controllable way and gain detailed insight into their chemical and magnetic properties. PMID:27454990

  1. Enhanced solar water splitting of electron beam irradiated titania photoanode by electrostatic spray deposition

    International Nuclear Information System (INIS)

    Highlights: • TiO2 thin-film photoelectrodes were prepared by electrostatic spray deposition (ESD). • Photoactivity of an electrosprayed titania film could be greatly enhanced by the use of electron beam irradiation. • The application of the electron beam was found to increase the photocurrent density threefold over a non-electron beam-treated film. - Abstract: Surface modifications are often made to titania films to improve its photocatalytic performance in water splitting. We herein introduced electron beam irradiation to enhance the photocatalytic activities of an electro-sprayed titania film for solar water splitting application. The film was fabricated by a facile and scalable electrostatic spraying deposition. According to SEM, X-ray diffraction, and Raman data, electron beam densified the film and improved its crystallinity. Absorbance data indicated that the band gap of the E-beam film reduced, which in turn covered the wider range of absorbed light. These modifications increased oxygen vacancies or defects, which enhanced mobility and separation of electrons and holes. As a result, the E-beam film exhibited a threefold increase in the photocurrent density, compared to that of the non-E-beam film. This electrosprayed titania film was used as a photoanode while the reference and counter electrodes involved in the generation of hydrogen were made of Ag/AgCl and platinum, respectively. The intensity of the UV light illumination used was 1 mW/cm2

  2. Electrochemical evaluation of under-deposit corrosion and its inhibition using the wire beam electrode method

    Energy Technology Data Exchange (ETDEWEB)

    Tan Yongjun, E-mail: yj.tan@curtin.edu.a [Western Australian Corrosion Research Group, Department of Chemistry, Curtin University, GPO Box U1987, Perth (Australia); Fwu, Young; Bhardwaj, Kriti [Western Australian Corrosion Research Group, Department of Chemistry, Curtin University, GPO Box U1987, Perth (Australia)

    2011-04-15

    Research highlights: A new experiment method for evaluating under-deposit corrosion and its inhibitors. Under-deposit corrosion did not occur in a CO{sub 2} saturated pure brine solution. Inhibitor imidazoline addition and O{sub 2} contamination initiated under-deposit corrosion. Inhibitor imidazoline reduced general corrosion but enhanced localised corrosion. - Abstract: A new experimental method has been applied to evaluate under-deposit corrosion and its inhibition by means of an electrochemically integrated multi-electrode array, namely the wire beam electrode (WBE). Maps showing galvanic current and corrosion potential distributions were measured from a WBE surface that was partially covered by sand. Under-deposit corrosion did not occur during the exposure of the WBE to carbon dioxide saturated brine under ambient temperature. The introduction of corrosion inhibitor imidazoline and oxygen into the brine was found to significantly affect the patterns and rates of corrosion, leading to the initiation of under-deposit corrosion over the WBE.

  3. Study of solid oxide fuel cell interconnects, protective coatings and advanced physical vapor deposition techniques

    Science.gov (United States)

    Gannon, Paul Edward

    High energy conversion efficiency, decreased environmentally-sensitive emissions and fuel flexibility have attracted increasing attention toward solid oxide fuel cell (SOFC) systems for stationary, transportation and portable power generation. Critical durability and cost issues, however, continue to impede wide-spread deployment. Many intermediate temperature (600-800°C) planar SOFC systems employ metallic alloy interconnect components, which physically connect individual fuel cells into electric series, facilitate gas distribution to appropriate SOFC electrode chambers (fuel/anode and oxidant[air]/cathode) and provide SOFC stack mechanical support. These demanding multifunctional requirements challenge commercially-available and inexpensive metallic alloys due to corrosion and related effects. Many ongoing investigations are aimed at enabling inexpensive metallic alloys (via bulk and/or surface modifications) as SOFC interconnects (SOFC(IC)s). In this study, two advanced physical vapor deposition (PVD) techniques: large area filtered vacuum arc deposition (LAFAD), and filtered arc plasma-assisted electron beam PVD (FA-EBPVD) were used to deposit a wide-variety of protective nanocomposite (amorphous/nanocrystalline) ceramic thin-film (1,000 hours); and, dramatically reduced Cr volatility (>30-fold). Analyses and discussions of SOFC(IC) corrosion, advanced PVD processes and protective coating behavior are intended to advance understanding and accelerate the development of durable and commercially-viable SOFC systems.

  4. Birth: A Neutral Beam Deposition Code for Non-Circular Tokamak Plasma

    International Nuclear Information System (INIS)

    A new neutral beam deposition code has been developed which is capable of calculating fast ion deposition profiles including the orbit correction. The code incorporates any injection geometry and a non-circular cross-section plasma with a variable elongation and an outward shift of the magnetic flux surface. Typical CPU time on a KL DEC-10 computer is 10--20 s and 5--10 s with and without the orbit correction, respectively. This is shorter by an order of magnitude than that of other codes, e.g., Monte Carlo beam deposition codes. The power deposition profile calculated by this code is in good agreement with that calculated by the Monte Carlo code which was developed to calculate the complete behaviors of the fast ions in circular plasmas

  5. Thermal stability of AlN films prepared by ion beam assisted deposition

    International Nuclear Information System (INIS)

    Highlights: • AlN films were deposited by dual ion beam sputtering. • Optical constants were measured by spectroscopic ellipsometry. • Diffuse reflection was measured by UV–vis spectroscopy. • Oxidized process of the AlN films was studied. - Abstract: The thermal stability of AlN films deposited by ion beam assisted deposition was performed at 600 °C for 192 h under air ambient. The composition, morphology and optical properties were studied by X-ray photoelectron spectrometer, transmission electron microscopy, scanning electron microscopy, spectroscopic ellipsometry and UV–vis spectroscopy. The results show that the deposited film is polycrystalline, smooth, dense and homogenous. The oxidation of grain boundary takes place due to the element diffusion in the polycrystalline material. Oxidation produces amorphous oxide layers on the surface of film. As annealing time increases, surface roughness and diffuse reflection increase. Annealing has little influence on refractive index and extinction coefficient

  6. Thermal stability of AlN films prepared by ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Jian-ping [Department of Energy Material and Technology, General Research Institute for Nonferrous Metals, Beijing 100088 (China); Liu, Xiao-peng, E-mail: xpgliu@yahoo.com.cn [Department of Energy Material and Technology, General Research Institute for Nonferrous Metals, Beijing 100088 (China); Fu, Zhi-qiang, E-mail: fuzq@cugb.edu.cn [School of Engineering and Technology, China University of Geosciences (Beijing), Beijing 100083 (China); Wang, Xiao-jing; Hao, Lei [Department of Energy Material and Technology, General Research Institute for Nonferrous Metals, Beijing 100088 (China)

    2015-08-30

    Highlights: • AlN films were deposited by dual ion beam sputtering. • Optical constants were measured by spectroscopic ellipsometry. • Diffuse reflection was measured by UV–vis spectroscopy. • Oxidized process of the AlN films was studied. - Abstract: The thermal stability of AlN films deposited by ion beam assisted deposition was performed at 600 °C for 192 h under air ambient. The composition, morphology and optical properties were studied by X-ray photoelectron spectrometer, transmission electron microscopy, scanning electron microscopy, spectroscopic ellipsometry and UV–vis spectroscopy. The results show that the deposited film is polycrystalline, smooth, dense and homogenous. The oxidation of grain boundary takes place due to the element diffusion in the polycrystalline material. Oxidation produces amorphous oxide layers on the surface of film. As annealing time increases, surface roughness and diffuse reflection increase. Annealing has little influence on refractive index and extinction coefficient.

  7. Electron-beam-directed vapor deposition of multifunctional structures for electrochemical storage

    Science.gov (United States)

    Queheillalt, Douglas T.; Hass, Derek D.; Wadley, Haydn N. G.

    2002-07-01

    Multifunctional structures are those, which combine load- bearing support in addition to additional functions such as mechanical actuation, distributed power supply or thermal management. Electron beam - directed vapor deposition technology has been used to investigate deposition methodologies for two multifunctional battery concepts: a linear/truss base nickel - metal hydride and a fiber based solid-state Li+ ion multifunctional battery. Porous nickel coatings for the cathodes and porous rare earth metal coatings based on La and Ni or Ti and Zr for the anodes are being investigated for the nickel - metal hydride system; where LiV2O5, LiPON, and Sn3N4 are being investigated for the Li+ ion based system. Electron beam - directed vapor deposition is being used for deposition of all cathode/anode structures to provide an economical method for the development of these novel multifunctional structures.

  8. Experimental measurements of the thermal conductivity of ash deposits: Part 1. Measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    A. L. Robinson; S. G. Buckley; N. Yang; L. L. Baxter

    2000-04-01

    This paper describes a technique developed to make in situ, time-resolved measurements of the effective thermal conductivity of ash deposits formed under conditions that closely replicate those found in the convective pass of a commercial boiler. Since ash deposit thermal conductivity is thought to be strongly dependent on deposit microstructure, the technique is designed to minimize the disturbance of the natural deposit microstructure. Traditional techniques for measuring deposit thermal conductivity generally do not preserve the sample microstructure. Experiments are described that demonstrate the technique, quantify experimental uncertainty, and determine the thermal conductivity of highly porous, unsintered deposits. The average measured conductivity of loose, unsintered deposits is 0.14 {+-} 0.03 W/(m K), approximately midway between rational theoretical limits for deposit thermal conductivity.

  9. Biaxially textured Ag films by grazing ion beam assisted deposition

    International Nuclear Information System (INIS)

    The effect of grazing incidence 4 keV Ar+ ion irradiation on the early stage of Ag thin film growth on amorphous Si was investigated. The double effect of axial and surface channeling resulted in grains oriented along the axis in-plane, while the (111) out-of-plane texture was maintained. A slight average tilt of the (111) out-of-plane texture axis towards the ion beam direction is proposed to result from the difference between terrace and step edge sputtering yield. The observed tilt is consistent with a minimum erosion orientation of the surface profile.

  10. Application of nuclear techniques for evaluation of coal, mineral deposits and environment

    International Nuclear Information System (INIS)

    Technical developments over the last 20 years have resulted in the use of a number of nuclear techniques , concepts and design in scientific research. The technology accumulated has now made it possible to initiate system definition for the needs of the user. Some recent applications of nuclear methods in the coal , mineral industry environmental research and other nuclear related activities such as gamma spectroscopy and electron beam are reviewed. In the coal industry in Turkey non-nuclear methods are now being used which are highly time consuming. There is a considerable demand for a rapid and sensitive method of monitoring coal ash in the coal industry. The technique described in the work was developed to meet requirements and using some assumptions and expressions has been applied to the determination of ash percent , sulphur content and calorific value in coal. Another study was undertaken primarily because few data exist documenting the concentration ratio ( CR ) of naturally occurring thorium in edible plants for human and farm animals around a thorium ore deposit in Turkey. During a two season period the concentration of thorium was determined in soil , native vegetation and barley within and around a typical thorium mine located in Kizilcaoren-Eskisehir. CR values of thorium were calculated for different samples and cases. The results are important in relation to the environmental issues of delivering doses to the tissues of animals and humans. One of the recent applications carried out was related to the mineral industry. This study presents results of the off-line EDXRF investigation on quality control of dressing of high grade iron deposit in Sivas-Divrigi which is located in the central part of Turkey. Techniques have been developed to determine the quality control of grinding , homogenization , separation , classification processes and residue materials in dry basis of the iron deposit.The results obtained increased the knowledge and performance of

  11. Coherent beam combination technique using SBS-PCM for high repetition rate lasers

    International Nuclear Information System (INIS)

    A plasma generation by laser-matter interaction is a powerful tool in the field of plasma research and applications. Recently, laser-induced plasma has been given a great attention, from material science to plasma deposition. However, current laser technologies have difficulty on increasing the laser power because of the thermal problems of the laser medium. The beam combination laser can overcome the thermal problems as it coherently combines multiple existing lasers without additional need for thermal management. H. J. Kong et al. developed the beam combination laser using the phase controlled stimulated Brillouin scattering phase conjugate mirrors (SBS-PCMs) has been developed. The key factor for achievement of the coherent combination is to overcome the randomness of the SBS phase. To lock/control the phases of the SBS waves, H. J. Kong et al. proposed and have developed a new phase control technique, so called “the self phase control technique.” The phase of each sub-beam can be controlled independently with the simplest arrangement. Thus, energy scaling is easily achieved by just increasing the number of the combined beams. The effective of this technique has been demonstrated experimentally over a decade. In this work, the phase control of a tiled four-beam combination laser is successfully performed with amplification. The relative phase fluctuations are measured from the interference pattern that is generated from the combined output beam and the reference beam. Without amplification, the combined output energy is 9.9 ± 0.5 mJ when the input energy is 32.2 ± 0.3 mJ. In this case, the standard deviations of the phase differences are measured to be λ/116, λ/38.9, λ/31.5, and λ/39.5, during 2,500 shots (250 s). When the amplifiers are operating, the combined output energy is 169 ± 6 mJ corresponding to the total gain of 5.3. In this case, the standard deviations of the phase differences are measured to be λ/68.8, λ/26.5, λ/28.0, and λ/26

  12. New diagnostic technique for Zeeman-compensated atomic beam slowing: technique and results

    OpenAIRE

    Molenaar, P.A.; Van Der Straten, P.; Heideman, H.G.M.; Metcalf, H.

    2001-01-01

    We have developed a new diagnostic tool for the study of Zeeman-compensated slowing of an alkali atomic beam. Our time-of-flight technique measures the longitudinal veloc- ity distribution of the slowed atoms with a resolution below the Doppler limit of 30 cm/s. Furthermore, it can map the position and velocity distribution of atoms in either ground hyperfine level inside the solenoid without any devices inside the solenoid. The technique reveals the optical pumping ef- fects, and shows in de...

  13. Effect of ion-beam assisted deposition on the film stresses of TiO2 and SiO2 and stress control

    Institute of Scientific and Technical Information of China (English)

    Yu-Qiong Li; Hua-Qing Wang; Wu-Yu Wang; Zhi-Nong Yu; He-Shan Liu; Gang Jin

    2012-01-01

    Based on Hartmann-Shack sensor technique,an online thin film stress measuring system was introduced to measure the film stresses of TiO2 and SiO2,and comparison was made between the film stresses prepared respectively by the conventional process and the ion-beam assisted deposition.The effect of ion-beam assisted deposition on the film stresses of TiO2 and SiO2 was investigated in details,and the stress control methodologies using on-line adjustment and film doping were put forward.The results show that the film stress value of TiO2 prepared by ion-beam assisted deposition is 40 MPa lower than that prepared by conventional process,and the stress of TiO2 film changes gradually from tensile stress into compressive stress with increasing ion energy; while the film stress of SiO2 is a tensile stress under ion-beam assisted deposition because of the ion-beam sputtering effect,and the film refractive index decreases with increasing ion energy.A dynamic film stress control can be achieved through in-situ adjustment of the processing parameters based on the online film stress measuring technique,and the intrinsic stress of film can be effectively changed through film doping.

  14. Energy deposition of heavy ions in the regime of strong beam-plasma correlations.

    Science.gov (United States)

    Gericke, D O; Schlanges, M

    2003-03-01

    The energy loss of highly charged ions in dense plasmas is investigated. The applied model includes strong beam-plasma correlation via a quantum T-matrix treatment of the cross sections. Dynamic screening effects are modeled by using a Debye-like potential with a velocity dependent screening length that guarantees the known low and high beam velocity limits. It is shown that this phenomenological model is in good agreement with simulation data up to very high beam-plasma coupling. An analysis of the stopping process shows considerably longer ranges and a less localized energy deposition if strong coupling is treated properly. PMID:12689203

  15. Ion Beam Induced Surface Modulations from Nano to Pico: Optimizing Deposition During Erosion and Erosion During Deposition

    International Nuclear Information System (INIS)

    Ion beams of sufficient energy to erode a surface can lead to surface modulations that depend on the ion beam, the material surface it impinges, and extrinsic parameters such as temperature and geometric boundary conditions. Focused Ion Beam technology both enables site-specific placement of these modulations and expedites research through fast, high dose and small efficient use of material. The DualBeam (FIB/SEM) enables in situ metrology, with movies observing ripple formation, wave motion, and the influence of line defects. Nanostructures (ripples of >400nm wavelength to dots spaced o etching enables deposition of organized structures 1000 times smaller than the aforementioned, video-recorded nanostructures. Orientation and position of these picostructures (naturally quantized by their atomic spacings) may be controlled by the same parameters as for nanostructures (e.g. ion inclination and imposed boundary conditions, which are flexibly regulated by FIB). Judicious control of angles during FIB-CVD growth stimulates erosion with directionality that produces surface modulations akin to those observed for sputtering. Just as a diamond surface roughens from 1-D ripples to 2-D steps with increasing angle of ion sputtering, so do ripples and steps appear on carbon-grown surfaces with increase in angle of FIB-CVD. Ion beam processing has been a stalwart of the microelectronics industry, is now a vital tool for research of self-organizing nanostructures, and promises to be a focus for future picotechnology

  16. Optimization of Neutron Beam Techniques for Haracterization of Structural Materials

    International Nuclear Information System (INIS)

    The result of the activities on the CRP project titled: Optimization of Neutron Beam Techniques for Characterization of Structural Materials has been reported. The activities consist of individual project which was proposed at the beginning of the project and collaborative works which is jointly carried out with the other members of the CRP. The individual project which is mainly focused on the optimization of the neutron diffractometer and neutron radiography has been sucessfully completed. The collaborative works which are mainly targeted to perform Round Robin exercise using VAMAS sample for neutron diffractometer and standard samples for tomography obtained from PSI have been carried out sucessfully. However, the texture measurement on Al alloys, applying data correction was not sucessfully achieved since the proper standard sample is not available and this is still needed for the the future plan. (author)

  17. SAR IMAGE ENHANCEMENT BASED ON BEAM SHARPENING TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    LIYong; ZI-IANGKun-hui; ZHUDai-yin; ZHUZhao-da

    2004-01-01

    A major problem encountered in enhancing SAR image is the total loss of phase information and the unknown parameters of imaging system. The beam sharpening technique, combined with synthetic aperture radiation pattern estimation provides an approach to process this kind of data to achieve higher apparent resolution. Based on the criterion of minimizing the expected quadratic estimation error, an optimum FIR filter with a symmetrical structure is designed whose coefficients depend on the azimuth response of local isolated prominent points because this response can be approximately regarded as the synthetic aperture radiation pattern of the imaging system. The point target simulation shows that the angular resolution is improved by a ratio of almost two to one. The processing results of a live SAR image demonstrate the validity of the method.

  18. Comparison of the dose deposited between the OBI system and the Varian TrueBeam Imaging system

    International Nuclear Information System (INIS)

    The use of imaging systems for positioning kilovoltage radiotherapy treatments has experienced a peak in recent years. Techniques such as IMRT, these systems are applied to a large number of sessions to ensure accurate positioning. This makes it increased the interest to know the dose deposited in the patient. Companies involved in developing new designs focus their efforts on reducing the dose due to these positioning systems. The aim of this study is to compare the dose delivered by the OBI image guidance system with the new system image TrueBeam, both of Varian, both planar imaging as CT (CBCT).

  19. Oxidation of nanostructured Ti films produced by low energy cluster beam deposition: An X-ray Photoelectron Spectroscopy characterization

    Energy Technology Data Exchange (ETDEWEB)

    Simone, Monica de, E-mail: desimone@tasc.infm.it [CNR-IOM Laboratorio TASC, Area Science Park Basovizza, 34149 Trieste (Italy); Snidero, Elena [CNR-IOM Laboratorio TASC, Area Science Park Basovizza, 34149 Trieste (Italy); Coreno, Marcello [CNR-IMIP, c/o Laboratorio TASC Area Science Park Basovizza, 34149 Trieste (Italy); Sincrotrone Trieste ScpA, Area Science Park Basovizza, 34149 Trieste (Italy); Bongiorno, Gero [Fondazione Filarete, v.le Ortles 22/4, 20139 Milano (Italy); Giorgetti, Luca [Istituto Europeo di Oncologia, Dip. di Oncologia Sperimentale, Via Adamello 16, 20139, Milano (Italy); Amati, Matteo [Sincrotrone Trieste ScpA, Area Science Park Basovizza, 34149 Trieste (Italy); Cepek, Cinzia [CNR-IOM Laboratorio TASC, Area Science Park Basovizza, 34149 Trieste (Italy)

    2012-05-01

    We used in-situ X-ray Photoelectron Spectroscopy (XPS) to study the oxidation process of a cluster-assembled metallic titanium film exposed to molecular oxygen at room temperature. The nanostructured film has been grown on a Si(111) substrate, in ultra high vacuum conditions, by coupling a supersonic cluster beam deposition system with an XPS experimental chamber. Our results show that upon in-situ oxygen exposure Ti{sup 3+} is the first oxidation state observed, followed by Ti{sup 4+}, whereas Ti{sup 2+} is practically absent during the whole process. Our results compare well with the existing literature on Ti films produced using other techniques.

  20. Oxidation of nanostructured Ti films produced by low energy cluster beam deposition: An X-ray Photoelectron Spectroscopy characterization

    International Nuclear Information System (INIS)

    We used in-situ X-ray Photoelectron Spectroscopy (XPS) to study the oxidation process of a cluster-assembled metallic titanium film exposed to molecular oxygen at room temperature. The nanostructured film has been grown on a Si(111) substrate, in ultra high vacuum conditions, by coupling a supersonic cluster beam deposition system with an XPS experimental chamber. Our results show that upon in-situ oxygen exposure Ti3+ is the first oxidation state observed, followed by Ti4+, whereas Ti2+ is practically absent during the whole process. Our results compare well with the existing literature on Ti films produced using other techniques.

  1. Relation between electrical resistivity and argon concentration of copper thin films prepared by ion-beam-assisted deposition

    International Nuclear Information System (INIS)

    Particle Induced X-ray Emission (PIXE) measurements were applied to the evaluation of the argon concentration in the copper thin films prepared by Ion-Beam-Assisted Deposition (IBAD) technique. The relation between electrical resistivity and argon concentration in the films were investigated. The crystallinity and the atomic density were also examined with x-ray diffraction and Rutherford Backscattering Spectrometry (RBS). The obtained results indicated that although the grain size of the films becomes larger with the ion irradiation, electrical resistivity increases with an increase in the ion quantity. (author)

  2. BIRTH: a beam deposition code for non-circular tokamak plasmas

    International Nuclear Information System (INIS)

    A new beam deposition code has been developed which is capable of calculating fast ion deposition profiles including the orbit correction. The code incorporates any injection geometry and a non-circular cross section plasma with a variable elongation and an outward shift of the magnetic flux surface. Typical cpu time on a DEC-10 computer is 10 - 20 seconds and 5 - 10 seconds with and without the orbit correction, respectively. This is shorter by an order of magnitude than that of other codes, e.g., Monte Carlo codes. The power deposition profile calculated by this code is in good agreement with that calculated by a Monte Carlo code. (author)

  3. Structural, optical, and conducting properties of crystalline ZnO:Co thin films grown by reactive electron beam deposition

    Energy Technology Data Exchange (ETDEWEB)

    Gürbüz, Osman; Güner, Sadık, E-mail: sguner@fatih.edu.tr; Büyükbakkal, Ömer; Çalışkan, Serkan

    2015-01-01

    We deposited an undoped ZnO and 6 different Co doped ZnO (ZnO:Co) thin films on fused silica (SiO{sub 2}) substrates with ∼100 nm thickness at substrate temperature of 125 °C using a Reactive Electron Beam Deposition technique. Energy-Dispersive X-ray Spectroscopy (EDS) was used to analyze the elemental composition rates of films. Elemental Co concentration varies from 4.62 to 28.77 at. %. The surface morphologies and grain sizes of thin films were investigated by Scanning Electron Microscope (SEM). The crystal and phase structures of the ZnO:Co thin films were characterized using X-ray diffraction (XRD). The films have single crystal and polycrystalline structures due to Co concentrations. Theoretical crystallite size and strain calculations were performed by applying the Scherrer and Williamson–Hall (W–H) methods. The grain sizes are 2–4 times greater than the crystalline sizes for ZnO:Co films. Optical properties of the films were studied by absorbance measurements using a UV–vis spectrophotometer. The analysis of the optical absorption spectra indicated that the energy band gap of the bulk ZnO film increased from 3.22 eV to maximum 4.17 eV upon Co deposition. Co{sup 2+} ion replaces Zn{sup 2+} ion in the structure without causing any remarkable defect for its hexagonal Wurtzite structure. Electrical conducting properties were investigated by using a Four Point Probe (FPP) technique. The conductivity depends on crystalline quality and Co concentration. - Highlights: • Fabrication of ZnO and ZnO:Co films through the Reactive Electron Beam deposition technique. • Reproducible single crystalline structured films. • Optical properties and band gap values were specified. • The conductivity depends on crystalline quality and Co concentration. • The films have potential for optoelectronic applications.

  4. Compositional study of silicon oxynitride thin films deposited using electron cyclotron resonance plasma-enhanced chemical vapor deposition technique

    International Nuclear Information System (INIS)

    We have used backscattering spectrometry and 15N(1H,α,γ)12C nuclear reaction analysis techniques to study in detail the variation in the composition of silicon oxynitride films with deposition parameters. The films were deposited using 2.45 GHz electron cyclotron resonance plasma-enhanced chemical vapor deposition (PECVD) technique from mixtures of precursors argon, nitrous oxide, and silane at deposition temperature 90 deg. C. The deposition pressure and nitrous oxide-to-silane gas flow rates ratio have been found to have a pronounced influence on the composition of the films. When the deposition pressure was varied for a given nitrous oxide-to-silane gas flow ratio, the amount of silicon and nitrogen increased with the deposition pressure, while the amount of oxygen decreased. For a given deposition pressure, the amount of incorporated nitrogen and hydrogen decreased while that of oxygen increased with increasing nitrous oxide-to-silane gas flow rates ratio. For nitrous oxide-to-silane gas flow ratio of 5, we obtained films which contained neither chemically bonded nor nonbonded nitrogen atoms as revealed by the results of infrared spectroscopy, backscattering spectrometry, and nuclear reaction analysis. Our results demonstrate the nitrogen-free nearly stoichiometric silicon dioxide films can be prepared from a mixture of precursors argon, nitrous oxide, and silane at low substrate temperature using high-density PECVD technique. This avoids the use of a hazardous and an often forbidden pair of silane and oxygen gases in a plasma reactor

  5. Ion beam analysis and spectrometry techniques for Cultural Heritage studies

    International Nuclear Information System (INIS)

    The implementation of experimental techniques for the characterisation of Cultural heritage materials has to take into account some requirements. The complexity of these past materials requires the development of new techniques of examination and analysis, or the transfer of technologies developed for the study of advanced materials. In addition, due to precious aspect of artwork it is also necessary to use the non-destructive methods, respecting the integrity of objects. It is for this reason that the methods using radiations and/or particles play a important role in the scientific study of art history and archaeology since their discovery. X-ray and γ-ray spectrometry as well as ion beam analysis (IBA) are analytical tools at the service of Cultural heritage. This report mainly presents experimental developments for IBA: PIXE, RBS/EBS and NRA. These developments were applied to the study of archaeological composite materials: layered materials or mixtures composed of organic and non-organic phases. Three examples are shown: evolution of silvering techniques for the production of counterfeit coinage during the Roman Empire and in the 16. century, the characterization of composites or mixed mineral/organic compounds such as bone and paint. In these last two cases, the combination of techniques gave original results on the proportion of both phases: apatite/collagen in bone, pigment/binder in paintings. Another part of this report is then dedicated to the non-invasive/non-destructive characterization of prehistoric pigments, in situ, for rock art studies in caves and in the laboratory. Finally, the perspectives of this work are presented. (author)

  6. Texture-Induced Anisotropy in an Inconel 718 Alloy Deposited Using Electron Beam Freeform Fabrication

    Science.gov (United States)

    Tayon, W.; Shenoy, R.; Bird, R.; Hafley, R.; Redding, M.

    2014-01-01

    A test block of Inconel (IN) 718 was fabricated using electron beam freeform fabrication (EBF(sup 3)) to examine how the EBF(sup 3) deposition process affects the microstructure, crystallographic texture, and mechanical properties of IN 718. Tests revealed significant anisotropy in the elastic modulus for the as-deposited IN 718. Subsequent tests were conducted on specimens subjected to a heat treatment designed to decrease the level of anisotropy. Electron backscatter diffraction (EBSD) was used to characterize crystallographic texture in the as-deposited and heat treated conditions. The anisotropy in the as-deposited condition was strongly affected by texture as evidenced by its dependence on orientation relative to the deposition direction. Heat treatment resulted in a significant improvement in modulus of the EBF(sup 3) product to a level nearly equivalent to that for wrought IN 718 with reduced anisotropy; reduction in texture through recrystallization; and production of a more homogeneous microstructure.

  7. Beam diagnostic techniques, observations and comparison with theory

    International Nuclear Information System (INIS)

    This paper presents the classes of the different methods of beam diagnostics available in modern storage rings. The first two use the near-field of the beam measured by the position monitors. The optical functions emdash betatron phase advances and beta functions emdash are obtained by exciting a betatron oscillation and measuring its phase and amplitude at the beam position monitors around the ring. Modern readout electronics, which memorize the readings taken in successive turns, are particularly well suited for this method. A second group of measurements is concerned with the properties of the beam itself. The frequency distribution of the particles can directly be deduced from the beam response to a harmonic excitation. Such measurements give also the beam stability and the impedance of the beam surroundings. The third class observes the far-field of the beam emitted as synchrotron radiation. Using this radiation for imaging or measuring its angular divergence gives the transverse beam dimensions

  8. A Comparative High-Resolution Electron Microscope Study of Ag Clusters Produced by a Sputter-Gas Aggregation and Ion Cluster Beam Technique

    Science.gov (United States)

    Hohl, Georg-Friedrich; Hihara, Takehiko; Sakurai, Masaki; Oishi, Takashi; Wakoh, Kimio; Sumiyama, Kenji; Suzuki, Kenji

    1994-03-01

    Ag clusters were formed by a sputter-gas-aggregation process [H. Haberland et al..: J. Vac. Sci. Technol. A 10 (1992) 3266] and the ionized cluster beam (ICB) [T. Takagi: Ionized-Cluster Beam Deposition and Epitaxy (Noyes, Park Ridge, 1988)] technique. The Ag clusters deposited on collodion-coated microgrids were investigated by high-resolution transmission electron microscopy. The diameter of those clusters, d, ranges from 1 nm up to about 10 nm for specimens produced by the sputter-gas aggregation technique, depending on the sputter condition and the deposition time. Comparable times of the ICB deposition lead to a broader distribution up to d≈20 nm, suggesting the formation of islands with extremely flat shapes. High percentages of crystalline particles obtained by both techniques are either single crystals or multiple twins with clear lattice images.

  9. Interfacial electrical properties of ion-beam sputter deposited amorphous carbon on silicon

    Science.gov (United States)

    Khan, A. A.; Woollam, J. A.; Chung, Y.; Banks, B.

    1983-01-01

    Amorphous, 'diamond-like' carbon films have been deposited on Si substrates, using ion-beam sputtering. The interfacial properties are studied using capacitance and conductance measurements. Data are analyzed using existing theories for interfacial electrical properties. The density of electronic states at the interface, along with corresponding time constants are determined.

  10. Research of photon beam dose deposition kernel based on Monte Carlo method

    International Nuclear Information System (INIS)

    Using Monte Carlo program BEAMnrc to simulate Siemens accelerator 6 MV photon beam, using BEAMdp program to analyse the energy spectrum distribution and mean energy from phase space data of different field sizes, then building beam source, energy spectrum and mono-energy source, to use DOSXYZnrc program to calculate the dose deposition kernels at dmax in standard water phantom with different beam sources and make comparison with different dose deposition kernels. The results show that the dose difference using energy spectrum source is small, the maximum percentage dose discrepancy is 1.47%, but it is large using mono-energy source, which is 6.28%. The maximum dose difference for the kernels derived from energy spectrum source and mono-energy source of the same field is larger than 9%, up to 13.2%. Thus, dose deposition has dependence on photon energy, it can lead to larger errors only using mono-energy source because of the beam spectrum distribution of accelerator. A good method to calculate dose more accurately is to use deposition kernel of energy spectrum source. (authors)

  11. Coating of pellet pressing tool with 12C by ion beam deposition

    International Nuclear Information System (INIS)

    The pressing tools, used in the preparation of the samples needed for example for such nuclear elemental analysis methods as PIXE, PIGE and RBS, have been coated with a diamond-type 12C-layer by ion beam deposition. Using carbon-coated pressing tools prepared in this way contamination of the sample surfaces during the pill pressing operation is avoided. (orig.)

  12. Copper thin films by ion beam assisted deposition: Strong texture, superior thermal stability and enhanced hardness

    International Nuclear Information System (INIS)

    Nanocrystalline metals generally exhibit exceptionally high strength. However, their susceptibility to grain growth restricts their applications in high temperature environments. The current study presents that nanocrystalline Cu thin films produced by ion beam assisted deposition (IBAD) are able to sustain their as-deposited microstructure and high hardness upon annealing at high temperatures. IBAD-Cu films exhibit a strong (1 1 1) fiber texture, which is caused by the ion beam induced effects of substrate cleaning, preferential damage and preferential sputtering. The microstructure of the IBAD-Cu films is stable at temperatures up to 800 °C (80% of the melting point of Cu). The hardness of the as-deposited IBAD-Cu films can reach a maximum value of 3.85 GPa. Even after annealing, their hardness is still much higher than that of the normally deposited (without ion beam) films as well as their bulk nanocrystalline counterparts before heat treatment. The excellent thermal stability of microstructure is attributed to the formation of nanometer-sized voids and their pinning effect on grain boundary migration. The kinetics of void formation, the contribution of twin boundaries and ion beam induced defects to the hardness are analyzed and discussed. The findings in this study demonstrate that IBAD is an effective method for the stabilization of microstructure and mechanical properties of nanocrystalline metal thin films

  13. Influence of the deposition techniques on the quality of the epitaxial buffer layers on textured Ni substrates

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, F.; Boffa, V.; Celentano, G.; Ciontea, L.; Galluzzi, V.; Petrisor, T. [ENEA, Rome (Italy). Centro Ricerche Frascati; Ceresara, S. [Centro Innovazione Lecco (Italy); Scardi, P. [Univ. di Trento (Italy). Dipt. di Ingegneria dei Materiali

    1999-04-20

    In order to fabricate high temperature superconducting tapes for power applications, the authors have analyzed different buffer layer architectures grown on textured Ni substrates suitable for YBCO deposition. Due to its optimal lattice matching the studied structures present as top layer a CeO{sub 2} film. The deposition of CeO{sub 2} on Ni substrates was performed by pulsed laser ablation and by e-beam evaporation at different temperatures. The films obtained by the two deposition techniques have not optimal structural properties, having a polycrystalline component. The misorientation of CeO{sub 2} is probably due to the formation of NiO at the interface between the film and the substrate during the deposition process even if no oxygen is introduced. In order to prevent Ni oxidation an intermediate 2000 {angstrom} Pd thick film was deposited by e-beam. Furthermore, the lattice mismatch between Pd and CeO{sub 2} is smaller than that between Ni and CeO{sub 2}. The Pd layer inhibits nickel oxide formation and improves the CeO{sub 2} epitaxial growth: the XRD pattern contains only the (001) peaks of Pd and CeO{sub 2}. SEM analysis on CeO{sub 2}/Pd/Ni shows a smooth surface free of cracks, contrary to that observed for CeO{sub 2}/Ni structure.

  14. Influence of the deposition techniques on the quality of the epitaxial buffer layers on textured Ni substrates

    International Nuclear Information System (INIS)

    In order to fabricate high temperature superconducting tapes for power applications, the authors have analyzed different buffer layer architectures grown on textured Ni substrates suitable for YBCO deposition. Due to its optimal lattice matching the studied structures present as top layer a CeO2 film. The deposition of CeO2 on Ni substrates was performed by pulsed laser ablation and by e-beam evaporation at different temperatures. The films obtained by the two deposition techniques have not optimal structural properties, having a polycrystalline component. The misorientation of CeO2 is probably due to the formation of NiO at the interface between the film and the substrate during the deposition process even if no oxygen is introduced. In order to prevent Ni oxidation an intermediate 2000 angstrom Pd thick film was deposited by e-beam. Furthermore, the lattice mismatch between Pd and CeO2 is smaller than that between Ni and CeO2. The Pd layer inhibits nickel oxide formation and improves the CeO2 epitaxial growth: the XRD pattern contains only the (001) peaks of Pd and CeO2. SEM analysis on CeO2/Pd/Ni shows a smooth surface free of cracks, contrary to that observed for CeO2/Ni structure

  15. Suspended nanostructures grown by electron beam-induced deposition of Pt and TEOS precursors

    International Nuclear Information System (INIS)

    Suspended nanostructures (SNSs) are grown by electron beam-induced deposition (EBID) of Pt and tetra-ethyl-ortho-silicate (TEOS) gas precursors on nanopillar tips, by lateral shifting of a scanning electron microscope beam. Shape evolution of SNSs is characterized as a function of electron energy (5, 10, 15 keV) and electron charge deposited per unit length (CDL, 1-9 pC nm-1 range) along the beam track. Pt SNSs grow as single nanowires, evolving from thin (15-20 nm) and horizontal to thick (up to 70 nm) and inclined (up to 600) geometry as CDL increases. TEOS SNSs consist of multiple nanowires arranged in a stack: horizontal and parallel along the beam shift direction and aligned on top of each other along the beam incidence axis. As the CDL increases, the number of nanowires increases and the top edge of the stack progressively inclines, taking the form of a hand-fan. Deposition yield and overall size of SNSs are found to be proportional to CDL and inversely proportional to electron energy for both Pt and TEOS precursors. As an example of 3D nanoarchitectures achievable by this lateral EBID approach, a 'nano-windmill' TEOS structure is presented

  16. On the magnetic properties of iron nanostructures fabricated via focused electron beam induced deposition and autocatalytic growth processes

    Science.gov (United States)

    Tu, F.; Drost, M.; Vollnhals, F.; Späth, A.; Carrasco, E.; Fink, R. H.; Marbach, H.

    2016-09-01

    We employ Electron beam induced deposition (EBID) in combination with autocatalytic growth (AG) processes to fabricate magnetic nanostructures with controllable shapes and thicknesses. Following this route, different Fe deposits were prepared on silicon nitride membranes under ultra-high vacuum conditions and studied by scanning electron microscopy (SEM) and scanning transmission x-ray microspectroscopy (STXM). The originally deposited Fe nanostructures are composed of pure iron, especially when fabricated via autocatalytic growth processes. Quantitative near-edge x-ray absorption fine structure (NEXAFS) spectroscopy was employed to derive information on the thickness dependent composition. X-ray magnetic circular dichroism (XMCD) in STXM was used to derive the magnetic properties of the EBID prepared structures. STXM and XMCD analysis evinces the existence of a thin iron oxide layer at the deposit–vacuum interface, which is formed during exposure to ambient conditions. We were able to extract magnetic hysteresis loops for individual deposits from XMCD micrographs with varying external magnetic field. Within the investigated thickness range (2–16 nm), the magnetic coercivity, as evaluated from the width of the hysteresis loops, increases with deposit thickness and reaches a maximum value of ∼160 Oe at around 10 nm. In summary, we present a viable technique to fabricate ferromagnetic nanostructures in a controllable way and gain detailed insight into their chemical and magnetic properties.

  17. High-purity 3D nano-objects grown by focused-electron-beam induced deposition

    Science.gov (United States)

    Córdoba, Rosa; Sharma, Nidhi; Kölling, Sebastian; Koenraad, Paul M.; Koopmans, Bert

    2016-09-01

    To increase the efficiency of current electronics, a specific challenge for the next generation of memory, sensing and logic devices is to find suitable strategies to move from two- to three-dimensional (3D) architectures. However, the creation of real 3D nano-objects is not trivial. Emerging non-conventional nanofabrication tools are required for this purpose. One attractive method is focused-electron-beam induced deposition (FEBID), a direct-write process of 3D nano-objects. Here, we grow 3D iron and cobalt nanopillars by FEBID using diiron nonacarbonyl Fe2(CO)9, and dicobalt octacarbonyl Co2(CO)8, respectively, as starting materials. In addition, we systematically study the composition of these nanopillars at the sub-nanometer scale by atom probe tomography, explicitly mapping the homogeneity of the radial and longitudinal composition distributions. We show a way of fabricating high-purity 3D vertical nanostructures of ∼50 nm in diameter and a few micrometers in length. Our results suggest that the purity of such 3D nanoelements (above 90 at% Fe and above 95 at% Co) is directly linked to their growth regime, in which the selected deposition conditions are crucial for the final quality of the nanostructure. Moreover, we demonstrate that FEBID and the proposed characterization technique not only allow for growth and chemical analysis of single-element structures, but also offers a new way to directly study 3D core–shell architectures. This straightforward concept could establish a promising route to the design of 3D elements for future nano-electronic devices.

  18. High-purity 3D nano-objects grown by focused-electron-beam induced deposition.

    Science.gov (United States)

    Córdoba, Rosa; Sharma, Nidhi; Kölling, Sebastian; Koenraad, Paul M; Koopmans, Bert

    2016-09-01

    To increase the efficiency of current electronics, a specific challenge for the next generation of memory, sensing and logic devices is to find suitable strategies to move from two- to three-dimensional (3D) architectures. However, the creation of real 3D nano-objects is not trivial. Emerging non-conventional nanofabrication tools are required for this purpose. One attractive method is focused-electron-beam induced deposition (FEBID), a direct-write process of 3D nano-objects. Here, we grow 3D iron and cobalt nanopillars by FEBID using diiron nonacarbonyl Fe2(CO)9, and dicobalt octacarbonyl Co2(CO)8, respectively, as starting materials. In addition, we systematically study the composition of these nanopillars at the sub-nanometer scale by atom probe tomography, explicitly mapping the homogeneity of the radial and longitudinal composition distributions. We show a way of fabricating high-purity 3D vertical nanostructures of ∼50 nm in diameter and a few micrometers in length. Our results suggest that the purity of such 3D nanoelements (above 90 at% Fe and above 95 at% Co) is directly linked to their growth regime, in which the selected deposition conditions are crucial for the final quality of the nanostructure. Moreover, we demonstrate that FEBID and the proposed characterization technique not only allow for growth and chemical analysis of single-element structures, but also offers a new way to directly study 3D core-shell architectures. This straightforward concept could establish a promising route to the design of 3D elements for future nano-electronic devices. PMID:27454835

  19. Double-beam pulsed laser deposition for the growth of Al-incorporated ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, L. [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad Universitaria, AP 70-186, C.P. 04510 México D.F., México (Mexico); Sánchez-Aké, C., E-mail: citlali.sanchez@ccadet.unam.mx [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad Universitaria, AP 70-186, C.P. 04510 México D.F., México (Mexico); Bizarro, M. [Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apartado Postal 70-186, C.P. 04510 México D.F., México (Mexico)

    2014-05-01

    Pulsed laser deposition in a delayed-double beam configuration is used to incorporate in situ Al in ZnO thin films. In this configuration, two synchronized pulsed-laser beams are employed to ablate independently a ZnO and an Al target. We investigated the effects of relative time delay of plasma plumes on the composition of the films with the aim of evaluating the performance of this technique to produce doped materials. Relative delay between plumes was found to control the incorporation of Al in the film in the range from 14% to 30%. However, to produce low impurity concentration of Al-doped ZnO (with Al incorporation less than 2%) the fluence used to produce the plasmas has more influence over the film composition than the relative plume delay. The minimum incorporation of Al corresponded to a relative delay of 0 μs, due to the interaction between plumes during their expansion.

  20. Investigations in CO2 laser beam caustics measuring techniques

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Bagger, Claus

    2004-01-01

    The performance of an industrial laser is very much depending upon the characteristics of the laser beam. The ISO standards 11146 and 11154 which are describing test methods for laser beam parameters have been approved....

  1. Improved performance over time of integration in momentum flux estimation using Postset Beam Steering technique

    Science.gov (United States)

    Anandan, V. K.; Kumar, Shridhar; Sureshbabu, V. N.; Rao, T. Narayana; Rao, M. Purnachandra; Tsuda, Toshitaka

    2014-12-01

    Using time series of vertical data collected from middle and upper atmospheric (MU) radar, the adaptive Capon beamforming technique is used to synthesize beams in the desired pointing directions within the radar beamwidth. Beam synthesis has been performed at the tilt angle of 1.5° with different beam configurations (4 beams, 8 beams, 16 beams, 32 beams, 48 beams and 64 beams), which are equally separated azimuth plane. The Power Spectral Density (PSD) is obtained from the synthesized beam using the eigenvector (EV) sub-space based spectral estimation method. The first moment is derived from the EV produced spectrum using the adaptive moment estimation method. From the first order moments derived along equally spaced pointing directions, radial wind velocities are readily obtained in the corresponding directions. From radial velocity obtained in various pointing directions, momentum flux of short duration (<2 h) is estimated using the symmetric beam method (SBM) which requires 4 symmetric beams separated by 90° in the azimuth plane. A comparative study has been performed to study the optimum beam configuration, required for the flux estimation, which shows that 32 beam configuration is sufficient to estimate the flux with least error. Study with 32 beam configuration, gives 8 sets of symmetric beams (8×4). Using 8 set of beams, the flux is estimated for each set of beams and averaged. The averaged flux is further integrated over different lengths of time up to 14 h. This systematic method for the estimation of momentum flux reveals that spatial averaging of beams in azimuth and integration over different lengths of time have reduced the time of integration from 15 to 16 h for the conventional approach to 8-9 h for the new approach using Postset Beam Steering (PBS) technique. The flux estimated with spatial-averaging of beam using PBS technique has been compared with other standard methods.

  2. Visible light active TiO2 films prepared by electron beam deposition of noble metals

    International Nuclear Information System (INIS)

    TiO2 films prepared by sol-gel method were modified by electron beam deposition of noble metals (Pt, Pd, and Ag). Effects of noble metals on the chemical and surface characteristics of the films were studied using XPS, TEM and UV-Vis spectroscopy techniques. Photocatalytic activity of modified TiO2 films was evaluated by studying the degradation of methyl orange dye solution under visible light UV irradiation. The result of TEM reveals that most of the surface area of TiO2 is covered by tiny particles of noble metals with diameter less than 1 nm. Broad red shift of UV-Visible absorption band of modified photocatalysts was observed. The catalytic degradation of methyl orange in aqueous solutions under visible light illumination demonstrates a significant enhancement of photocatalytic activity of these films compared with the un-loaded films. The photocatalytic efficiency of modified TiO2 films by this method is affected by the concentration of impregnating solution.

  3. Visible light active TiO 2 films prepared by electron beam deposition of noble metals

    Science.gov (United States)

    Hou, Xing-Gang; Ma, Jun; Liu, An-Dong; Li, De-Jun; Huang, Mei-Dong; Deng, Xiang-Yun

    2010-03-01

    TiO 2 films prepared by sol-gel method were modified by electron beam deposition of noble metals (Pt, Pd, and Ag). Effects of noble metals on the chemical and surface characteristics of the films were studied using XPS, TEM and UV-Vis spectroscopy techniques. Photocatalytic activity of modified TiO 2 films was evaluated by studying the degradation of methyl orange dye solution under visible light UV irradiation. The result of TEM reveals that most of the surface area of TiO 2 is covered by tiny particles of noble metals with diameter less than 1 nm. Broad red shift of UV-Visible absorption band of modified photocatalysts was observed. The catalytic degradation of methyl orange in aqueous solutions under visible light illumination demonstrates a significant enhancement of photocatalytic activity of these films compared with the un-loaded films. The photocatalytic efficiency of modified TiO 2 films by this method is affected by the concentration of impregnating solution.

  4. Ferroelectric polarization and resistive switching characteristics of ion beam assisted sputter deposited BaTiO3 thin films

    Science.gov (United States)

    Silva, J. P. B.; Kamakshi, Koppole; Sekhar, K. C.; Moreira, J. Agostinho; Almeida, A.; Pereira, M.; Gomes, M. J. M.

    2016-05-01

    In this work, 150 nm thick polycrystalline BaTiO3 (BTO) films were deposited on Pt/TiO2/SiO2/Si substrate by ion beam assisted sputter deposition technique. The bias voltage dependent resistive switching (RS) and ferroelectric polarization characteristics of Au/BTO/Pt devices are investigated. The devices display the stable bipolar RS characteristics without an initial electroforming process. Fittings to current-voltage (I-V) curves suggest that low and high resistance states are governed, respectively, by filamentary model and trap controlled space charge limited conduction mechanism, where the oxygen vacancies act as traps. Presence of oxygen vacancies is evidenced from the photoluminescence spectrum. The devices also display P-V loops with remnant polarization (Pr) of 5.7 μC/cm2 and a coercive electric field (Ec) of 173.0 kV/cm. The coupling between the ferroelectric polarization and RS effect in BTO films is demonstrated.

  5. Molecular beam deposition of high-permittivity polydimethylsiloxane for nanometer-thin elastomer films in dielectric actuators

    DEFF Research Database (Denmark)

    M. Weiss, Florian; Madsen, Frederikke Bahrt; Töpper, Tino;

    2016-01-01

    dielectric properties. To produce elastomer layers nanometers thin, molecular beam deposition was introduced. We pursue the synthesis of a high-permittivity oligomer, namely a chloropropyl-functional, vinyl-terminated siloxane to be thermally evaporated and subsequent UV curing to form an elastomer. The......To realize low-voltage dielectric elastomer actuators (DEAs) for artificial muscles, a high-permittivity elastomer and a related thin-film deposition technique must be selected. For polydimethylsiloxane, fillers or functionalized crosslinkers have been incorporated into the elastomer to improve...... monitoring. Using atomic force microscopy, the film surface morphology and mechanics were characterized after growth termination and subsequent curing. The Young's modulus of the elastomer corresponded to (1.8 ± 0.2) MPa and is thus a factor of two lower than that of DMS-V05. Consequently, the properties of...

  6. Effect of Hydrogen ion beam irradiation onto the FIR reflectivity of pulsed laser deposited mirror like Tungsten films

    International Nuclear Information System (INIS)

    Graphical abstract: The specular FIR reflectivity of the W1, W2, W3 and W4 mirrors before and after 8 keV Hydrogen ion beam irradiation. Highlights: ► Mirror like W thin films were obtained via PLD. ► The maximum thickness of the Tungsten thin film was ∼324 nm. ► Effect of H-ion beam irradiation on the quality of PLD W mirror is reported. ► Post exposure reflectivity of Tungsten thin films was hardly changed by 2%. - Abstract: The optical quality of the First Mirrors (FMs) of a fusion device (burning plasma experiments, ITER) deteriorates due to the erosion by charge exchange neutrals, re-deposition of the eroded material and the lattice damage by the bombardment of the high energetic particles. This degradation of the optical quality of the plasma facing components in such a harsh environment is a serious concern for the reliability of the spectroscopic based optical diagnostics using FM of a fusion device. In this paper, the effect of 8 keV Hydrogen ion beam irradiation onto the FIR reflectivity of Tungsten thin film mirror is presented. The Tungsten thin films were prepared via Pulsed Laser Deposition (PLD) technique. The Tungsten mirrors were subjected to X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX), Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) for characterization. The specular reflectivities of the Tungsten mirrors before and after exposure to ion beam were recorded with Fourier Transform of Infra-Red (FTIR) technique. The ion penetration depth and straggle into Tungsten thin film and stainless steel (SS) substrate were estimated by Transport of Ions in Matter (TIRM) simulation code. The changes in post exposure IR reflectivity were interpreted in terms of these parameters.

  7. Very high temperature chemical vapor deposition of new carbon thin films using organic semiconductor molecular beam sources

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Takuya [Department of Chemistry, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan); Shimada, Toshihiro, E-mail: shimada@chem.s.u-tokyo.ac.j [Department of Chemistry, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan); Hanzawa, Akinori; Hasegawa, Tetsuya [Department of Chemistry, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan)

    2009-11-30

    We carried out the preparation and characterization of new carbon films deposited using an organic molecular beam deposition apparatus with very high substrate temperature (from room temperature to 2670 K), which we newly developed. When we irradiated molecular beam of organic semiconductor perylene tetracarboxylic acid dianhydride (PTCDA) on Y{sub 0.07}Zr{sub 0.93}O{sub 2} (111) at 2170 K, a new carbon material was formed via decomposition and fusing of the molecules. The films were characterized with an atomic force microscope (AFM), Raman spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Zirconium carbide (ZrC) films were identified beneath the topmost carbon layer by XRD and XPS analyses, which results from chemical reactions of the substrate and the molecules. Partially graphitized aromatic rings of PTCDA were observed from Raman spectroscopy. The present technique - very high temperature chemical vapor deposition using organic semiconductor sources - will be useful to study a vast unexplored field of covalent carbon solids.

  8. Processing for optically active erbium in silicon by film co-deposition and ion-beam mixing

    International Nuclear Information System (INIS)

    Techniques of film deposition by co-evaporation, ion-beam assisted mixing, oxygen ion implantation, and thermal annealing were been combined in a novel way to study processing of erbium-in-silicon thin-film materials for optoelectronics applications. Structures with erbium concentrations above atomic solubility in silicon and below that of silicide compounds were prepared by vacuum co-evaporation from two elemental sources to deposit 200-270 nm films on crystalline silicon substrates. Ar+ ions were implanted at 300 keV. Oxygen was incorporated by O+-ion implantation at 130 keV. Samples were annealed at 600 deg. C in vacuum. Concentration profiles of the constituent elements were obtained by Rutherford backscattering spectrometry. Results show that diffusion induced by ion-beam mixing and activated by thermal annealing depends on the deposited Si-Er profile and reaction with implanted oxygen. Room temperature photoluminescence spectra show Er3+ transitions in a 1480-1550 nm band and integrated intensities that increase with the oxygen-to-erbium ratio.

  9. Investigation of ZnO thin films deposited on ferromagnetic metallic buffer layer by molecular beam epitaxy toward realization of ZnO-based magnetic tunneling junctions

    International Nuclear Information System (INIS)

    Deposition of ZnO thin films on a ferromagnetic metallic buffer layer (Co3Pt) by molecular beam epitaxy technique was investigated for realization of ZnO-based magnetic tunneling junctions with good quality hexagonal ZnO films as tunnel barriers. For substrate temperature of 600 °C, ZnO films exhibited low oxygen defects and high electrical resistivity of 130 Ω cm. This value exceeded that of hexagonal ZnO films grown by sputtering technique, which are used as tunnel barriers in ZnO-MTJs. Also, the effect of oxygen flow during deposition on epitaxial growth conditions and Co3Pt surface oxidation was discussed.

  10. New control techniques for extraction of bevalac beams

    International Nuclear Information System (INIS)

    Beams of accelerated heavy ions can now be delivered as one-second-long dc pulses with minimal fluctuations in instantaneous flux. Pulse duration can be held constant to within 1% while keeping a high non-varying extraction efficiency which minimizes pulse-to-pulse position shift in the extracted beam. In addition, differing beam intensities over several orders of magnitude can be delivered. Computer adjustment of all measurement and control devices results in linear operation over three orders of magnitude of beam intensity. Control of beam structure is accomplished by a unique combination of dual slope integrators and phase forward ''predictive'' circuits in the feedback loop

  11. Metallization on FDM Parts Using the Chemical Deposition Technique

    Directory of Open Access Journals (Sweden)

    Azhar Equbal

    2014-08-01

    Full Text Available Metallization of ABS (acrylonitrile-butadiene-styrene parts has been studied on flat part surfaces. These parts are fabricated on an FDM (fused deposition modeling machine using the layer-wise deposition principle using ABS as a part material. Electroless copper deposition on ABS parts was performed using two different surface preparation processes, namely ABS parts prepared using chromic acid for etching and ABS parts prepared using a solution mixture of sulphuric acid and hydrogen peroxide (H2SO4/H2O2 for etching. After surface preparations using these routes, copper (Cu is deposited electrolessly using four different acidic baths. The acidic baths used are 5 wt% CuSO4 (copper sulfate with 15 wt% of individual acids, namely HF (hydrofluoric acid, H2SO4 (sulphuric acid, H3PO4 (phosphoric acid and CH3COOH (acetic acid. Cu deposition under different acidic baths used for both the routes is presented and compared based on their electrical performance, scanning electron microscopy (SEM and energy dispersive X-ray spectrometry (EDS. The result shows that chromic acid etched samples show better electrical performance and Cu deposition in comparison to samples etched via H2SO4/H2O2.

  12. Effect of focused ion beam deposition induced contamination on the transport properties of nano devices

    International Nuclear Information System (INIS)

    Focused ion beam (FIB) deposition produces unwanted particle contamination beyond the deposition point. This is due to the FIB having a Gaussian distribution. This work investigates the spatial extent of this contamination and its influence on the electrical properties of nano-electronic devices. A correlation study is performed on carbon-nanotube (CNT) devices manufactured using FIB deposition. The devices are observed using transmission electron microscopy (TEM) and these images are correlated with device electrical characteristics. To discover how far Pt-nanoparticle contamination occurs along a CNT after FIB electrical contact deposition careful TEM inspections are performed. The results show FIB deposition efficiently improves electrical contact; however, the practice is accompanied by serious particle contamination near deposition points. These contaminants include metal particles and amorphous elements originating from precursor gases and residual water molecules in the vacuum chamber. Pt-contamination extends for approximately 2 μm from the point of FIB contact deposition. These contaminants cause current fluctuations and alter the transport characteristics of devices. It is recommended that nano-device fabrication occurs at a distance greater than 2 μm from the FIB deposition of an electrical contact. (paper)

  13. Electron-beam induced deposition and autocatalytic decomposition of Co(CO3NO

    Directory of Open Access Journals (Sweden)

    Florian Vollnhals

    2014-07-01

    Full Text Available The autocatalytic growth of arbitrarily shaped nanostructures fabricated by electron beam-induced deposition (EBID and electron beam-induced surface activation (EBISA is studied for two precursors: iron pentacarbonyl, Fe(CO5, and cobalt tricarbonyl nitrosyl, Co(CO3NO. Different deposits are prepared on silicon nitride membranes and silicon wafers under ultrahigh vacuum conditions, and are studied by scanning electron microscopy (SEM and scanning transmission X-ray microscopy (STXM, including near edge X-ray absorption fine structure (NEXAFS spectroscopy. It has previously been shown that Fe(CO5 decomposes autocatalytically on Fe seed layers (EBID and on certain electron beam-activated surfaces, yielding high purity, polycrystalline Fe nanostructures. In this contribution, we investigate the growth of structures from Co(CO3NO and compare it to results obtained from Fe(CO5. Co(CO3NO exhibits autocatalytic growth on Co-containing seed layers prepared by EBID using the same precursor. The growth yields granular, oxygen-, carbon- and nitrogen-containing deposits. In contrast to Fe(CO5 no decomposition on electron beam-activated surfaces is observed. In addition, we show that the autocatalytic growth of nanostructures from Co(CO3NO can also be initiated by an Fe seed layer, which presents a novel approach to the fabrication of layered nanostructures.

  14. The electron beam deposition of titanium on polyetheretherketone (PEEK) and the resulting enhanced biological properties.

    Science.gov (United States)

    Han, Cheol-Min; Lee, Eun-Jung; Kim, Hyoun-Ee; Koh, Young-Hag; Kim, Keung N; Ha, Yoon; Kuh, Sung-Uk

    2010-05-01

    The surface of polyetheretherketone (PEEK) was coated with a pure titanium (Ti) layer using an electron beam (e-beam) deposition method in order to enhance its biocompatibility and adhesion to bone tissue. The e-beam deposition method was a low-temperature coating process that formed a dense, uniform and well crystallized Ti layer without deteriorating the characteristics of the PEEK implant. The Ti coating layer strongly adhered to the substrate and remarkably enhanced its wettability. The Ti-coated samples were evaluated in terms of their in vitro cellular behaviors and in vivo osteointegration, and the results were compared to a pure PEEK substrate. The level of proliferation of the cells (MC3T3-E1) was measured using a methoxyphenyl tetrazolium salt (MTS) assay and more than doubled after the Ti coating. The differentiation level of cells was measured using the alkaline phosphatase (ALP) assay and also doubled. Furthermore, the in vivo animal tests showed that the Ti-coated PEEK implants had a much higher bone-in-contact (BIC) ratio than the pure PEEK implants. These in vitro and in vivo results suggested that the e-beam deposited Ti coating significantly improved the potential of PEEK for hard tissue applications. PMID:20153890

  15. Selective atomic layer deposition with electron-beam patterned self-assembled monolayers

    International Nuclear Information System (INIS)

    The authors selectively deposited nanolines of titanium oxide (TiO2) through atomic layer deposition (ALD) using an octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) as a nucleation inhibition layer. Electron-beam (e-beam) patterning is used to prepare nanoline patterns in the OTS SAM on SiO2/Si substrates suitable for selective ALD. The authors have investigated the effect of an e-beam dose on the pattern width of the selectively deposited TiO2 lines. A high dose (e.g., 20 nC/cm) causes broadening of the linewidth possibly due to scattering, while a low dose (e.g., 5 nC/cm) results in a low TiO2 deposition rate because of incomplete exposure of the OTS SAMs. The authors have confirmed that sub-30 nm isolated TiO2 lines can be achieved by selective ALD combined with OTS patterned by EBL at an accelerating voltage of 2 kV and line dose of 10 nC/cm. This research offers a new approach for patterned gate dielectric layer fabrication, as well as potential applications for nanosensors and solar cells.

  16. Study of electron-beam-pumped KrF laser kinetics and calculation of energy deposition

    International Nuclear Information System (INIS)

    The program of the electron-beam-pumped KrF laser kinetics has been developed. By using this program the relation of relaxation rate of upper laser level to the optimum output condition of the KrF laser is studied. It is expected that the laser output will be directly proportional to the relaxation rate under a given condition when the laser flux is near saturation. The numerical simulation showed that a rise (or drop) in pump rate is faster than that of the relaxation rate, the laser output rises (or drops) as well. The optimum condition of output is obtained. The pressure (5 ∼ 6 atm*), the pump power and the Ar, Kr, F2 mixture ratio are determined for the optimum condition. In order to study the energy deposition of the electron-beam-pumped KrF gas laser, the SANDYL and the ITS programs have been developed. The latter is the program with the axial magnetic field applied, while the former without any field. The energy depositions of two kinds of Ar/Kr/F2 mixtures at various pressures of the electron-beam-pumped cylindrical KrF laser are calculated with the SANDYL program. The results show that under the same conditions, the energy deposition with the axial magnetic field applied is 3 times larger than that without any magnetic field. The energy depositions of two kinds of Ar/Kr/F2

  17. Fabrication and characterization of graded calcium phosphate coatings produced by ion beam sputtering/mixing deposition

    International Nuclear Information System (INIS)

    Ion beam sputtering/mixing deposition was used to produce thin calcium phosphate coatings on titanium substrate from the hydroxyapatite target. It was found that as-deposited coatings were amorphous. No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were present for CO32-, which was brought about during the deposition process. Scanning electron microscopy revealed that the deposited coatings had a uniform and dense structure. The calcium to phosphorous ratio of these coatings varied between 2.0 and 8.0. Analyses of XPS data revealed that the coating could be divided into four distinctive zones, and a graded structure was achieved in the as-received coating. Scratch tests showed that the coatings adhered well to the substrate

  18. Nanoscale Soldering of Positioned Carbon Nanotubes using Highly Conductive Electron Beam Induced Gold Deposition

    DEFF Research Database (Denmark)

    Madsen, Dorte Nørgaard; Mølhave, Kristian; Mateiu, Ramona Valentina; Bøggild, Peter; Rasmussen, A.M.; Appel, C.C.; Brorson, M; Jacobsen, C.J.H.

    2003-01-01

    We have developed an in-situ method for controlled positioning of carbon nanotubes followed by highly conductive contacting of the nanotubes, using electron beam assisted deposition of gold. The positioning and soldering process takes place inside an Environmental Scanning Electron Microscope (E...... embedded in a carbon matrix. Nanoscale soldering of multi-walled carbon nanotubes (MWNT) onto microelectrodes was achieved by deposition of a conducting gold line across a contact point between nanotube and electrode. The solderings were found to be mechanically stronger than the carbon nanotubes. We have......-SEM) in the presence of a source of gold-organic precursor gas. Bridges deposited between suspended microelectrodes show resistivities down to 10-4 Ωcm and Transmission Electron Microscopy (TEM) of the deposits reveals a dense core of gold particles surrounded by a crust of small gold nanoparticles...

  19. An orientation competition in yttria-stabilized zirconia thin films fabricated by ion beam assisted sputtering deposition

    International Nuclear Information System (INIS)

    A previously found orientation competition in ion beam sputtered yttria-stabilized zirconia thin films was studied in detail. The effects of sputtering energy and deposition angle were analyzed in ion sputtered films without assisting ions bombardment. It is found that for normally deposited films, (001) and (011) orientations are favored at low and high sputtering energy respectively. For inclined substrate deposited films, as deposition angle increases, (001), (011) and (111) orientations are advantaged in turn. The results can be attributed to the in-plane energy exchange of deposition atom and adatoms. In ion beam assisting deposited YSZ films of low assisting ions energy and current, a (001) oriented biaxial texture is gradually induced as ion energy increased. In the case of ion beam assisted inclined deposition of 45°, (001) orientation is enhanced and two preferential in-plane orientations are found coexist.

  20. Nanocrystalline biphasic resorbable calcium phosphate (HAp/β-TCP) thin film prepared by electron beam evaporation technique

    Energy Technology Data Exchange (ETDEWEB)

    Elayaraja, K.; Chandra, V. Sarath; Joshy, M.I. Ahymah; Suganthi, R.V. [Crystal Growth Centre, Anna University, Chennai 600025, Tamil Nadu (India); Asokan, K. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Kalkura, S. Narayana, E-mail: kalkura@yahoo.com [Crystal Growth Centre, Anna University, Chennai 600025, Tamil Nadu (India)

    2013-06-01

    Biphasic calcium phosphate (BCP) thin film having resorbable β-tricalcium phosphate (β-TCP) and non-resorbable hydroxyapatite (HAp) phases having enhanced bioactivity was synthesized by electron beam evaporation technique. Nanosized BCP was deposited as a layer (500 nm) on (0 0 1) silicon substrate by electron beam evaporation and crystalline phase of samples were found to improve on annealing at 700 °C. Uniform deposition of calcium phosphate on silicon substrate was verified from elemental mapping using scanning electron microscope (SEM-EDX). Annealing of the samples led to a decrease in surface roughness, hydrophobicity and dissolution of the coating layer. Amoxicillin loaded thin films exhibited significant bacterial resistance. In addition, BCP thin films did not exhibit any cytotoxicity. Antibiotics incorporated BCP coated implants might prevent the post-surgical infections and could promote bone-bonding of orthopedic devices.

  1. Nanocrystalline biphasic resorbable calcium phosphate (HAp/β-TCP) thin film prepared by electron beam evaporation technique

    International Nuclear Information System (INIS)

    Biphasic calcium phosphate (BCP) thin film having resorbable β-tricalcium phosphate (β-TCP) and non-resorbable hydroxyapatite (HAp) phases having enhanced bioactivity was synthesized by electron beam evaporation technique. Nanosized BCP was deposited as a layer (500 nm) on (0 0 1) silicon substrate by electron beam evaporation and crystalline phase of samples were found to improve on annealing at 700 °C. Uniform deposition of calcium phosphate on silicon substrate was verified from elemental mapping using scanning electron microscope (SEM-EDX). Annealing of the samples led to a decrease in surface roughness, hydrophobicity and dissolution of the coating layer. Amoxicillin loaded thin films exhibited significant bacterial resistance. In addition, BCP thin films did not exhibit any cytotoxicity. Antibiotics incorporated BCP coated implants might prevent the post-surgical infections and could promote bone-bonding of orthopedic devices.

  2. Angular distribution of species in pulsed energy beam deposition of oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Nistor, M., E-mail: mnistor@infim.ro [National Institute for Lasers, Plasmas and Radiation Physics, L22 P.O. Box MG-36, 77125 Bucharest-Magurele (Romania); Gherendi, F.; Mandache, N.B. [National Institute for Lasers, Plasmas and Radiation Physics, L22 P.O. Box MG-36, 77125 Bucharest-Magurele (Romania)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Thickness profiles of Ba{sub x}Sr{sub 1-x}TiO{sub 3} thin films were measured. Black-Right-Pointing-Pointer Comparison between pulsed laser (PLD) and pulsed electron beam deposition (PED). Black-Right-Pointing-Pointer The film thicknesses profile of PED has a slightly broader shape than that of PLD. Black-Right-Pointing-Pointer The film stoichiometry is preserved at all angles. - Abstract: Pulsed energy beam deposition methods like pulsed-laser deposition (PLD) or pulsed-electron beam deposition (PED) allow the formation of smooth, dense and crystalline oxide thin films. The angular distribution of the ablated flux from the target and the thin film thickness profile were extensively studied for PLD for a wide range of materials and growth conditions. In the case of complex oxide compounds, the angular distribution of the various species emitted by the target will determine the precise composition of the films. In this work we report on the determination of the angular distributions of the species emitted from a Ba{sub x}Sr{sub 1-x}TiO{sub 3} (BST) target. A comparison between these results obtained by PED and PLD methods is presented and discussed in the frame of Anisimov's model. A slightly broader shape of the angular distribution for PED than that for PLD is explained taking into account the differences in the spot size and fluence between the pulsed electron beam and laser beam and a small collisional broadening of the angular distribution in the case of PED. The stoichiometry is preserved at all angles.

  3. Crystalline Indium Sulphide thin film by photo accelerated deposition technique

    Science.gov (United States)

    Dhanya, A. C.; Preetha, K. C.; Deepa, K.; Remadevi, T. L.

    2015-02-01

    Indium sulfide thin films deserve special attention because of its potential application as buffer layers in CIGS based solar cells. Highly transparent indium sulfide (InS) thin films were prepared using a novel method called photo accelerated chemical deposition (PCD). Ultraviolet source of 150 W was used to irradiate the solution. Compared to all other chemical methods, PCD scores its advantage for its low cost, flexible substrate and capable of large area of deposition. Reports on deposition of high quality InS thin films at room temperature are very rare in literature. The precursor solution was initially heated to 90°C for ten minutes and then deposition was carried out at room temperature for two hours. The appearance of the film changed from lemon yellow to bright yellow as the deposition time increased. The sample was characterized for its structural and optical properties. XRD profile showed the polycrystalline behavior of the film with mixed phases having crystallite size of 17 nm. The surface morphology of the films exhibited uniformly distributed honey comb like structures. The film appeared to be smooth and the value of extinction coefficient was negligible. Optical measurements showed that the film has more than 80% transmission in the visible region. The direct band gap energy was 2.47eV. This method is highly suitable for the synthesis of crystalline and transparent indium sulfide thin films and can be used for various photo voltaic applications.

  4. Deposition of diamond like carbon films by using a single ion gun with varying beam source

    Institute of Scientific and Technical Information of China (English)

    JIANG Jin-qiu; Chen Zhu-ping

    2001-01-01

    Diamond like carbon films have been successfully deposited on the steel substrate, by using a single ion gun with varying beam source. The films may appear blue, yellow and transparent in color, which was found related to contaminants from the sample holder and could be avoided. The thickness of the films ranges from tens up to 200 nanometers, and the hardness is in the range 20 to 30 GPa. Raman analytical results reveal the films are in amorphous structure. The effects of different beam source on the films structure are further discussed.

  5. Growth of textured MgO through e-beam evaporation and inclined substrate deposition

    International Nuclear Information System (INIS)

    Long length textured MgO template on Hastelloy C276(TM) (HC) has been successfully deposited in a reel-to-reel (R2R) electron beam (e-beam) evaporation system by inclined substrate deposition (ISD). High deposition rate up to 10 nm s-1 with exposure length of 7 cm has been realized. The MgO template showed good in-plane texture of 9.5 deg. -11.5 deg. measured from the (002) phi scans. Experimental results reveal that MgO in-plane texture is formed by the preferred growth direction of [11n] parallel substrate normal and one of the MgO {200} planes rotates to the in-flux direction. A new expression, termed the 'two-thirds relationship', between the inclination angle α and the tilted angle of the (00l) plane from the substrate normal, β, has been summarized. YBa2Cu3O7-δ (YBCO) film deposited by pulsed laser deposition (PLD) on strontium ruthenate (SRO) buffered ISD MgO showed Tc of 91 K with transition width of 1 K. Critical current measurement indicated an Ic of 110 A cm-1 at 77 K in self-field for 0.68 μm YBCO film, corresponding to a Jc of 1.6 MA cm-2

  6. Growth of textured MgO through e-beam evaporation and inclined substrate deposition

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y [Materials Research Lab, UES Inc. Dayton, OH 45432 (United States); Lei, C H [Department of MSE, University of Illinois, Urbana, IL 61801 (United States); Ma, B [Argonne National Laboratory, Argonne, IL 60439 (United States); Evans, H [Materials Research Lab, UES Inc. Dayton, OH 45432 (United States); Efstathiadis, H [Albany Nanotech, Albany, NY 12203 (United States); Manisha, R [Albany Nanotech, Albany, NY 12203 (United States); Massey, M [Materials Research Lab, UES Inc. Dayton, OH 45432 (United States); Balachandran, U [Argonne National Laboratory, Argonne, IL 60439 (United States); Bhattacharya, R [Materials Research Lab, UES Inc. Dayton, OH 45432 (United States)

    2006-08-15

    Long length textured MgO template on Hastelloy C276(TM) (HC) has been successfully deposited in a reel-to-reel (R2R) electron beam (e-beam) evaporation system by inclined substrate deposition (ISD). High deposition rate up to 10 nm s{sup -1} with exposure length of 7 cm has been realized. The MgO template showed good in-plane texture of 9.5 deg. -11.5 deg. measured from the (002) phi scans. Experimental results reveal that MgO in-plane texture is formed by the preferred growth direction of [11n] parallel substrate normal and one of the MgO {l_brace}200{r_brace} planes rotates to the in-flux direction. A new expression, termed the 'two-thirds relationship', between the inclination angle {alpha} and the tilted angle of the (00l) plane from the substrate normal, {beta}, has been summarized. YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) film deposited by pulsed laser deposition (PLD) on strontium ruthenate (SRO) buffered ISD MgO showed T{sub c} of 91 K with transition width of 1 K. Critical current measurement indicated an I{sub c} of 110 A cm{sup -1} at 77 K in self-field for 0.68 {mu}m YBCO film, corresponding to a J{sub c} of 1.6 MA cm{sup -2}.

  7. Growth of textured MgO through e-beam evaporation and inclined substrate deposition

    Science.gov (United States)

    Xu, Y.; Lei, C. H.; Ma, B.; Evans, H.; Efstathiadis, H.; Manisha, R.; Massey, M.; Balachandran, U.; Bhattacharya, R.

    2006-08-01

    Long length textured MgO template on Hastelloy C276™ (HC) has been successfully deposited in a reel-to-reel (R2R) electron beam (e-beam) evaporation system by inclined substrate deposition (ISD). High deposition rate up to 10 nm s-1 with exposure length of 7 cm has been realized. The MgO template showed good in-plane texture of 9.5°-11.5° measured from the (002) phi scans. Experimental results reveal that MgO in-plane texture is formed by the preferred growth direction of [11n]\\parallel \\mathrm {substrate} normal and one of the MgO {200} planes rotates to the in-flux direction. A new expression, termed the 'two-thirds relationship', between the inclination angle α and the tilted angle of the (00l) plane from the substrate normal, β, has been summarized. YBa2Cu3O7-δ (YBCO) film deposited by pulsed laser deposition (PLD) on strontium ruthenate (SRO) buffered ISD MgO showed Tc of 91 K with transition width of 1 K. Critical current measurement indicated an Ic of 110 A cm-1 at 77 K in self-field for 0.68 µm YBCO film, corresponding to a Jc of 1.6 MA cm-2.

  8. Electron beam evaporated LaF3 thin films prepared by different temperatures and deposition rates

    International Nuclear Information System (INIS)

    LaF3 thin films were prepared by electron beam evaporation with different temperatures and deposition rates. Microstructure properties including crystalline structure and surface roughness were investigated by X-ray diffraction (XRD) and optical profilograph. X-ray photoelectron spectroscopy (XPS) was employed to study the chemical composition of the films. Optical properties (transmittance and refractive index) and laser induce damage threshold (LIDT) at 355 nm of the films were also characterized. The effects of deposition rate and substrate temperature on microstructure, optical properties and LIDT of LaF3 thin films were discussed, respectively.

  9. Adherence of ion beam sputter deposited metal films on H-13 steel

    Science.gov (United States)

    Mirtich, M. J.

    1980-01-01

    An electron bombardment argon ion source was used to sputter deposit 17 different metal and metal oxide films ranging in thickness from 1 to 8 micrometers on H-13 steel substrates. The film adherence to the substrate surface was measured using a tensile test apparatus. Comparisons in bond strength were made between ion beam, ion plating, and RF deposited films. A protective coating to prevent heat checking in H-13 steel dies used for aluminum die casting was studied. The results of exposing the coated substrates to temperatures up to 700 degrees are presented.

  10. Microanalyses of the hydroxyl—poly—calcium sodium phosphate coatings produced by ion beam assisted deposition

    Institute of Scientific and Technical Information of China (English)

    LIUZhong-Yang; WANGChang-Xing; 等

    2002-01-01

    Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36.

  11. Some techniques to improve time structure of slow extracted beam

    International Nuclear Information System (INIS)

    In order to improve the time structure of slow extracted beam spill for the KEK 12GeV PS, the spill control system has been upgraded by adding feed forward signal to feedback signal. Further, the wake field in the RF cavity has been cancelled by the beam bunch signal to reduce the re-bunch effect during extraction period. (author)

  12. Ion-beam inertial fusion: the requirements posed by target and deposition physics

    International Nuclear Information System (INIS)

    The demonstration of ICF scientific feasibility requires success in target design, driver development and target fabrication. Since these are interrelated, we present here some results of ion beam target studies and relate them to parameters of interest to ion accelerators. Ion deposition physics have long been a well known subject apart from high beam currents. Recent NRL experiments at up to 250 kA/cm2 ions confirm the classical deposition physics now at current densities which are comparable to most ion targets. On the other hand, GSI data at low current density but 1 to 10 MeV/nucleon are continually being accumulated. They have yet to find anomalous results. Relying on target concepts outlined briefly, we report on the energy gain of ion-driven fusion targets as a function of input energy, ion ranges and focal spot radius. We also comment on some consequences of target gain versus driver and reactor requirements

  13. Atomic layer deposition of HfO2 on graphene through controlled ion beam treatment

    Science.gov (United States)

    Kim, Ki Seok; Oh, Il-Kwon; Jung, Hanearl; Kim, Hyungjun; Yeom, Geun Young; Kim, Kyong Nam

    2016-05-01

    The polymer residue generated during the graphene transfer process to the substrate tends to cause problems (e.g., a decrease in electron mobility, unwanted doping, and non-uniform deposition of the dielectric material). In this study, by using a controllable low-energy Ar+ ion beam, we cleaned the polymer residue without damaging the graphene network. HfO2 grown by atomic layer deposition on graphene cleaned using an Ar+ ion beam showed a dense uniform structure, whereas that grown on the transferred graphene (before Ar+ ion cleaning) showed a non-uniform structure. A graphene-HfO2-metal capacitor fabricated by growing 20-nm thick HfO2 on graphene exhibited a very low leakage current (graphene, whereas a similar capacitor grown using the transferred graphene showed high leakage current.

  14. The Technique of Genetic Transformation Mediated by keV Ion Beam

    Institute of Scientific and Technical Information of China (English)

    卞坡; 余增亮

    2005-01-01

    The application of keV ion beam in life science started in China several decades ago. In 1986, researchers initially studied the mutagenic effect of ion beam, and successfully applied it to plant breeding. Nowadays, ion beam implantation technique has been extensively applied to many biological fields. This paper mainly introduces one of its important applications: genetic transformation mediated by keV ion beam.

  15. Ion beam deposition of amorphous carbon films with diamond like properties

    Science.gov (United States)

    Angus, John C.; Mirtich, Michael J.; Wintucky, Edwin G.

    1982-01-01

    Carbon films were deposited on silicon, quartz, and potassium bromide substrates from an ion beam. Growth rates were approximately 0.3 micron/hour. The films were featureless and amorphous and contained only carbon and hydrogen in significant amounts. The density and carbon/hydrogen ratio indicate the film is a hydrogen deficient polymer. One possible structure, consistent with the data, is a random network of methylene linkages and tetrahedrally coordinated carbon atoms.

  16. An adaptive laser beam shaping technique based on a genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    Ping Yang; Yuan Liu; Wei Yang; Minwu Ao; Shijie Hu; Bing Xu; Wenhan Jiang

    2007-01-01

    @@ A new adaptive beam intensity shaping technique based on the combination of a 19-element piezo-electricity deformable mirror (DM) and a global genetic algorithm is presented. This technique can adaptively adjust the voltages of the 19 actuators on the DM to reduce the difference between the target beam shape and the actual beam shape. Numerical simulations and experimental results show that within the stroke range of the DM, this technique can be well used to create the given beam intensity profiles on the focal plane.

  17. The Energy Deposition for No-air-gap Design of the TESLA Beam Dump

    International Nuclear Information System (INIS)

    In the linear electron- positron collider project TESLA, the beam dump designed as a water tank is working in a very special regime. Each pulse of the electron or positron beam should, after crossing the interaction region, be dumped in a cylindrical 10-m long water dump. The mean power to be absorbed is important being 8 MW for 250 GeV beam energy (intensity 2.04 * 1014 electrons/s) and for 400 GeV case it will be 12 MW and 2.8*1014 electrons/s. The initial project was providing a 20-cm wide air gap between the titanium vessel containing water and the concentrate outer shield. Energy deposition calculations using FLUKA code showed that the energy deposited in and thus temperature rise of the concrete shield were very high. Additional solid inner shield made of aluminium (or iron) has to be placed just behind the titanium vessel. The important production of radioactive nuclei in the air has prompted the designers to minimize the air gap. Realistically, this minimal size of the air gap was assessed to be a 2-cm wide. Also new thickness of the inner shield has been proposed - 60 cm for aluminium and 20 cm for iron. These changes called for a new set of calculations for energy deposition in both the concentrate and aluminum iron) shields. (author)

  18. Ion beam deposition and surface characterization of thin multi-component oxide films during growth.

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, A.R.; Im, J.; Smentkowski, V.; Schultz, J.A.; Auciello, O.; Gruen, D.M.; Holocek, J.; Chang, R.P.H.

    1998-01-13

    Ion beam deposition of either elemental targets in a chemically active gas such as oxygen or nitrogen, or of the appropriate oxide or nitride target, usually with an additional amount of ambient oxygen or nitrogen present, is an effective means of depositing high quality oxide and nitride films. However, there are a number of phenomena which can occur, especially during the production of multicomponent films such as the ferroelectric perovskites or high temperature superconducting oxides, which make it desirable to monitor the composition and structure of the growing film in situ. These phenomena include thermodynamic (Gibbsian), and oxidation or nitridation-driven segregation, enhanced oxidation or nitridation through production of a highly reactive gas phase species such as atomic oxygen or ozone via interaction of the ion beam with the target, and changes in the film composition due to preferential sputtering of the substrate via primary ion backscattering and secondary sputtering of the film. Ion beam deposition provides a relatively low background pressure of the sputtering gas, but the ambient oxygen or nitrogen required to produce the desired phase, along with the gas burden produced by the ion source, result in a background pressure which is too high by several orders of magnitude to perform in situ surface analysis by conventional means. Similarly, diamond is normally grown in the presence of a hydrogen atmosphere to inhibit the formation of the graphitic phase.

  19. Lift-Off technique using different e-beam writers

    Czech Academy of Sciences Publication Activity Database

    Chlumská, Jana; Kolařík, Vladimír; Krátký, Stanislav; Matějka, Milan; Urbánek, Michal; Horáček, Miroslav

    Ostrava: TANGER Ltd, 2013, s. 286-290. ISBN 978-80-87294-47-5. [NANOCON 2013. International Conference /5./. Brno (CZ), 16.10.2013-18.10.2013] R&D Projects: GA MŠk ED0017/01/01; GA MŠk EE.2.3.20.0103; GA TA ČR TE01020233 Institutional support: RVO:68081731 Keywords : Lift –Off * electron-beam lithography * e–beam writers with shaped and Gaussian beam Subject RIV: BH - Optics, Masers, Lasers

  20. Relativistic electron beam energy deposition in thin gold and aluminum targets

    International Nuclear Information System (INIS)

    Relativistic electron beam (REB) energy deposition in thin gold and aluminum targets has been investigated experimentally using radiation temperature measurements in the soft x-ray, vacuum ultraviolet (XUV) and optical spectral regions on two different particle accelerators. Energy deposition measurements were compared with numerical calculations utilizing particle-in-cell (PIC) diode codes, condensed history Monte-Carlo codes, and coupled radiation-hydrodynamic codes. The specific power deposited (i.e., power deposited/unit mass) was observed to be greater than that due to an average electron making a single pass through a thin target (6.4 μm thick gold foil on the Hydra accelerator and 38 and 6 μm thick aluminum foils on the Proto I accelerator). Self-magnetic field effects were primarily responsible for deposition enhancement in 6.4 μm gold foils on the Hydra accelerator (ν/γ approx. = 2.5). Reduction of electron scattering with aluminum foils on Proto I where ν/γ approx. = 1 led to deposition enhancement due to both self electric and magnetic fields

  1. Ion beam sputter deposition of TiNi shape memory alloy thin films

    Science.gov (United States)

    Davies, Sam T.; Tsuchiya, Kazuyoshi

    1999-08-01

    The development of functional or smart materials for integration into microsystem is of increasing interest. An example is the shape memory effect exhibited by certain metal alloys which, in principle, can be exploited in the fabrication of micro-scale manipulators or actuators, thereby providing on-chip micromechanical functionality. We have investigated an ion beam sputter deposition process for the growth of TiNi shape memory alloy thin films and demonstrated the required control to produce equiatomic composition, uniform coverage and atomic layer-by-layer growth rates on engineering surfaces. The process uses argon ions at intermediate energy produced by a Kaufman-type ion source to sputter non-alloyed targets of high purity titanium and nickel. Precise measurements of deposition rates allows compositional control during thin film growth. As the sputtering targets and substrates are remote from the discharge plasma, deposition occurs under good vacuum of approximately 10-6 mtorr thus promoting high quality films. Furthermore, the ion beam energetics allow deposition at relatively low substrate temperatures of heat capacity and thermal conductivity as the TiNi shape memory alloy undergoes martensitic to austenitic phase transformations.

  2. AMORPHIZATION IN Nb-M (M=Fe, Co, Ni) BINARY METAL SYSTEMS INDUCED BY ION BEAM ASSISTED DEPOSITION (IBAD)

    Institute of Scientific and Technical Information of China (English)

    F. Pan; F. Zeng; B. Zhao

    2002-01-01

    Ion beam assisted deposition technique (IBAD) was utilized to systematically studyamorphization in binary metal systems of Nb-magnetic element, i.e., Nb-M (M=Fe,Co or Ni). The glass forming range terned as Nb fraction of Nb-Fe system was about34at.% to 56at.%, that of Nb-Co system was about 32at.% to 72at.% and that of Nb-Ni about 20at.% to 80at.%. Similar percolation patterns were found in amorphousalloy films. The fractal dimensions of the percolation patterns approach to 2, whichindicates 2-D layer growth for amorphous phases. It is regarded that the assistedAr+ ion beam duringthe deposition process plays important role for the 2-D layergrowth. Some metastable crystalline phases were obtained in these three systems byIBAD, e.g., bcc supersaturated solid solutions in Nb-Fe and Nb-Co systems, fcc andhcp phases in Nb-Co and Nb-Ni systems. The formation and competing between theamorphous and the metastable crystalline phases were determined by both the phases'thermodynamic states in binary metal systems and kinetics during IBAD process.

  3. Fabrication of single TiO2 nanotube devices with Pt interconnections using electron- and ion-beam-assisted deposition

    Science.gov (United States)

    Lee, Mingun; Cha, Dongkyu; Huang, Jie; Ha, Min-Woo; Kim, Jiyoung

    2016-06-01

    Device fabrication using nanostructured materials, such as nanotubes, requires appropriate metal interconnections between nanotubes and electrical probing pads. Here, electron-beam-assisted deposition (EBAD) and ion-beam-assisted deposition (IBAD) techniques for fabrication of Pt interconnections for single TiO2 nanotube devices are investigated. IBAD conditions were optimized to reduce the leakage current as a result of Pt spreading. The resistivity of the IBAD-Pt was about three orders of magnitude less than that of the EBAD-Pt, due to low carbon concentration and Ga doping, as indicated by X-ray photoelectron spectroscopy analysis. The total resistances of single TiO2 nanotube devices with EBAD- or IBAD-Pt interconnections were 3.82 × 1010 and 4.76 × 108 Ω, respectively. When the resistivity of a single nanotube is low, the high series resistance of EBAD-Pt cannot be ignored. IBAD is a suitable method for nanotechnology applications, such as photocatalysis and biosensors.

  4. Unveiling the optical properties of a metamaterial synthesized by electron-beam-induced deposition.

    Science.gov (United States)

    Woźniak, P; Höflich, K; Brönstrup, G; Banzer, P; Christiansen, S; Leuchs, G

    2016-01-15

    Direct writing using a focused electron beam allows for fabricating truly three-dimensional structures of sub-wavelength dimensions in the visible spectral regime. The resulting sophisticated geometries are perfectly suited for studying light-matter interaction at the nanoscale. Their overall optical response will strongly depend not only on geometry but also on the optical properties of the deposited material. In the case of the typically used metal-organic precursors, the deposits show a substructure of metallic nanocrystals embedded in a carbonaceous matrix. Since gold-containing precursor media are especially interesting for optical applications, we experimentally determine the effective permittivity of such an effective material. Our experiment is based on spectroscopic measurements of planar deposits. The retrieved permittivity shows a systematic dependence on the gold particle density and cannot be sufficiently described using the common Maxwell-Garnett approach for effective medium. PMID:26629782

  5. Unveiling the optical properties of a metamaterial synthesized by electron-beam-induced deposition

    CERN Document Server

    Woźniak, Paweł; Brönstrup, Gerald; Banyer, Peter; Christiansen, Silke; Leuchs, Gerd

    2015-01-01

    The direct writing using a focused electron beam allows for fabricating truly three-dimensional structures of sub-wavelength dimensions in the visible spectral regime. The resulting sophisticated geometries are perfectly suited for studying light-matter interaction at the nanoscale. Their overall optical response will strongly depend not only on geometry but also on the optical properties of the deposited material. In case of the typically used metal-organic precursors, the deposits show a substructure of metallic nanocrystals embedded in a carbonaceous matrix. Since gold-containing precursor media are especially interesting for optical applications, we experimentally determine the effective permittivity of such an effective material. Our experiment is based on spectroscopic measurements of planar deposits. The retrieved permittivity shows a systematic dependence on the gold particle density and cannot be sufficiently described using the common Maxwell-Garnett approach for effective medium.

  6. PREFACE 12th International Workshop on Slow Positron Beam Techniques

    Science.gov (United States)

    Buckman, Stephen; Sullivan, James; White, Ronald

    2011-01-01

    Preface These proceedings arose from the 12th International Workshop on Slow Positron Beam Techniques (SLOPOS12), which was held on Magnetic Island, North Queensland, Australia, between 1-6th August 2010. Meetings in the SLOPOS series are held (roughly) every three years and have now been held on (almost) all continents, indicating the truly international nature of the field. SLOPOS12 marked the second time that the Workshop had been held in the southern hemisphere, and the first time in Australia. SLOPOS12 attracted 122 delegates from 16 countries. Most encouraging was the attendance of 28 student delegates, and that about half of the overall delegates were early career researchers - a good sign for the future of our field. We also enjoyed the company of more than a dozen partners and families of delegates. In a slight departure from previous SLOPOS meetings, the International Advisory Committee approved a broader scope of scientific topics for inclusion in the program for the 2010 Workshop. This broader scope was intended to capture the applications of positrons in atomic, molecular and biomedical areas and was encapsulated in the byeline for SLOPOS-12: The 12th International Workshop on Slow Positron Beam Techniques for Solids, Surfaces, Atoms and Molecules. The scientific and social program for the meeting ran over 6 days with delegates gathering on Sunday August 1st and departing on August 6th. The scientific program included plenary, invited, contributed and student lectures, the latter being the subject of a student prize. In all there were 53 oral presentations during the week. There were also two poster sessions, with 63 posters exhibited, and a prize was awarded for the best poster by a student delegate. The standard of the student presentations, both oral and posters, was outstanding, so much so that the judging panel recommended an additional number of prizes be awarded. Topics that were the focus of invited presentations and contributed papers at

  7. Coating of ceramic powders by chemical vapor deposition techniques (CVD)

    International Nuclear Information System (INIS)

    New ceramic materials with selected advanced properties can be designed by coating of ceramic powders prior to sintering. By variation of the core and coating material a large number of various powders and ceramic materials can be produced. Powders which react with the binder phase during sintering can be coated with stable materials. Thermal expansion of the ceramic materials can be adjusted by varying the coating thickness (ratio core/layer). Electrical and wear resistant properties can be optimized for electrical contacts. A fluidized bed reactor will be designed which allow the deposition of various coatings on ceramic powders. (author)

  8. A feasibility study of H{sup -} beam extraction technique using YAG laser

    Energy Technology Data Exchange (ETDEWEB)

    Meigo, Shin-ichiro; Hasegawa, Kazuo; Ikeda, Yujiro; Oigawa, Hiroyuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Aoki, Nobutada [Toshiba Power System Co., Ltd. (Japan); Nakagawa, Satoshi [Toshiba Co., Tokyo (Japan)

    2002-12-01

    Under a framework of JAERI-KEK joint project of high intensity proton accelerator, as for research and develop of the accelerator driven nuclear transmutation of the long lived radioactive nuclide, it is planed to built the Transmutation Physics Experiment Facility (TEF-P) and the Transmutation Engineering Experiment Facility (TEF-E). The TEF-P is used for the experiments for subcritical system coupled with a spallation neutron target bombarded with 600-MeV proton beam accelerated by the LINAC. To limit the maximum thermal power less than 500 W at the TEF-P, an incident beam power should be less than 10 W. On the contrary, at the TEF-E, high power beam of 200 kW is requested. Both high and low power beams are demanded for the transmutation facilities. It is difficult to deliver a low power beam to the TEF-P. Conventional beam extraction technique with a thin foil, is not desirable because the scattering of the beam at the foil requires the massive shield. Therefore, we study a new technique to extract a small portion of the beam precisely from the high intensity beam by using a laser beam. By a laser beam, H{sup -} in the beam from LINAC is partially changed to H{sup 0} beam so that a low current H{sup 0} beam can be obtained. As the cross section of the charge exchange reaction for H{sup -} ions has a peak around at a wave length of 1 {mu}m for photons, YAG laser is suitable for this charge exchange because of its 1.06 {mu}m wave length. It is derived that 10 W beam for 600-MeV proton can be extracted by the YAG laser with power of 2 J for each pulse of 25 Hz. By this technique, the pulse width for the extracted beam can be controlled by changing the time width of laser irradiation. When a charge exchanger having the beam collide point existing in straight section, a background beam current of projectile, however, will be increased due to the interaction with the residual gas in the beam duct. Thus, a charge exchanger is devised having the beam collide point in a

  9. Investigation of physical vapor deposition techniques of conformal shell coating for core/shell structures by Monte Carlo simulations

    International Nuclear Information System (INIS)

    Vertically aligned core/shell nanowire (nanorod) arrays are favorable candidates in many nano-scale devices such as solar cells, detectors, and integrated circuits. The quality of the shell coating around nanowire arrays is as crucial as the quality of the nanowires in device applications. For this reason, we worked on different physical vapor deposition (PVD) techniques and conducted Monte Carlo simulations to estimate the best deposition technique for a conformal shell coating. Our results show that a small angle (≤ 45°) between incoming flux of particles and the substrate surface normal is necessary for PVD techniques with a directional incoming flux (e.g. thermal or e-beam evaporation) for a reasonable conformal coating. On the other hand, PVD techniques with an angular flux distribution (e.g. sputtering) can provide a fairly conformal shell coating around nanowire arrays without a need of small angle deposition. We also studied the shape effect of the arrays on the conformality of the coating and discovered that arrays of the tapered-top nanorods and the pyramids can be coated with a more conformal and thicker coating compared to the coating on the arrays of flat-top nanowires due to their larger openings in between structures. Our results indicate that conventional PVD techniques, which offer low cost and large scale thin film fabrication, can be utilized for highly conformal and uniform shell coating formation in core/shell nanowire device applications. - Highlights: • We examined the shell coating growth in core/shell nanostructures. • We investigated the effect of physical vapor deposition method on the conformality of the shell. • We used Monte Carlo simulations to simulate the shell growth on nanowire templates. • Angular atomic flux (i.e., sputtering at high pressure) leads to conformal and uniform coatings. • A small angle (< 45°) to the directional flux needs to be introduced for conformal coatings

  10. Investigation of physical vapor deposition techniques of conformal shell coating for core/shell structures by Monte Carlo simulations

    Energy Technology Data Exchange (ETDEWEB)

    Cansizoglu, H., E-mail: hxis@ualr.edu; Yurukcu, M.; Cansizoglu, M.F.; Karabacak, T.

    2015-05-29

    Vertically aligned core/shell nanowire (nanorod) arrays are favorable candidates in many nano-scale devices such as solar cells, detectors, and integrated circuits. The quality of the shell coating around nanowire arrays is as crucial as the quality of the nanowires in device applications. For this reason, we worked on different physical vapor deposition (PVD) techniques and conducted Monte Carlo simulations to estimate the best deposition technique for a conformal shell coating. Our results show that a small angle (≤ 45°) between incoming flux of particles and the substrate surface normal is necessary for PVD techniques with a directional incoming flux (e.g. thermal or e-beam evaporation) for a reasonable conformal coating. On the other hand, PVD techniques with an angular flux distribution (e.g. sputtering) can provide a fairly conformal shell coating around nanowire arrays without a need of small angle deposition. We also studied the shape effect of the arrays on the conformality of the coating and discovered that arrays of the tapered-top nanorods and the pyramids can be coated with a more conformal and thicker coating compared to the coating on the arrays of flat-top nanowires due to their larger openings in between structures. Our results indicate that conventional PVD techniques, which offer low cost and large scale thin film fabrication, can be utilized for highly conformal and uniform shell coating formation in core/shell nanowire device applications. - Highlights: • We examined the shell coating growth in core/shell nanostructures. • We investigated the effect of physical vapor deposition method on the conformality of the shell. • We used Monte Carlo simulations to simulate the shell growth on nanowire templates. • Angular atomic flux (i.e., sputtering at high pressure) leads to conformal and uniform coatings. • A small angle (< 45°) to the directional flux needs to be introduced for conformal coatings.

  11. Micro-beam and pulsed laser beam techniques for the micro-fabrication of diamond surface and bulk structures

    International Nuclear Information System (INIS)

    Micro-fabrication in diamond is applicable in a wide set of emerging technologies, exploiting the exceptional characteristics of diamond for application in bio-physics, photonics and radiation detection. Micro ion-beam irradiation and pulsed laser irradiation are complementary techniques, which permit the implementation of complex geometries, by modification and functionalization of surface and/or bulk material, modifying the optical, electrical and mechanical characteristics of the material. In this article we summarize the work done in Florence (Italy), concerning ion beam and pulsed laser beam micro-fabrication in diamond

  12. Mechanical and tribological properties of carbon thin film with tungsten interlayer prepared by Ion beam assisted deposition

    Czech Academy of Sciences Publication Activity Database

    Vlčák, P.; Černý, F.; Tolde, Z.; Sepitka, J.; Gregora, Ivan; Daniš, S.

    2013-01-01

    Roč. 2013, FEB (2013). ISSN 2314-4874 Institutional support: RVO:68378271 Keywords : carbon coatings * ion beam deposition * XRD * nanoindentation Subject RIV: BM - Solid Matter Physics ; Magnetism http://dx.doi.org/10.1155/2013/630156

  13. Crystal structure and microwave resistance of YBa2Cu3O7-δ films prepared by cross-beam pulsed-laser deposition

    International Nuclear Information System (INIS)

    High-Tc superconducting YBa2Cu3O7-δ (YBCO) films were prepared by a unique pulsed-laser deposition using crossed-laser-beam technique onto LaAlO3 substrates in order to develop a basic technology for microwave-device application. The pulsed-laser deposition set-up uses two Nd-YAG lasers with 1064 nm wavelength and 0.3 J/pulse power. The unique feature of this method is a possibility to get a plasma plume with a low level of 'droplet', which essentially improves the film-surface quality. Transmission-electron microscopy and x-ray data show that YBCO films deposited at substrate temperature (Ts) of 780 deg. C exhibit a minimal density of dislocations in the crystal. YBCO films deposited at Ts = 780 deg. C with a cooling rate of V = 3 K min-1 have the smallest surface resistance below the transition temperature

  14. The Development of a Differential Deposition Technique for Figure Correction in Grazing Incidence Optics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the development of a physical-vapor-deposition coating technique to correct residual figure errors in grazing-incidence optics. The process involves...

  15. Absolute beam flux measurement at NDCX-I using gold-melting calorimetry technique

    International Nuclear Information System (INIS)

    We report on an alternative way to measure the absolute beam flux at the NDCX-I, LBNL linear accelerator. Up to date, the beam flux is determined from the analysis of the beam-induced optical emission from a ceramic scintilator (Al-Si). The new approach is based on calorimetric technique, where energy flux is deduced from the melting dynamics of a gold foil. We estimate an average 260 kW/cm2 beam flux over 5 (micro)s, which is consistent with values provided by the other methods. Described technique can be applied to various ion species and energies.

  16. Nanophotonic Fabrication Self-Assembly and Deposition Techniques

    CERN Document Server

    Yatsui, Takashi

    2012-01-01

    Nanophotonics, a novel optical technology, utilizes the local interaction between nanometric particles via optical near fields. The optical near fields are the elementary surface excitations on nanometric particles, i.e. dressed photons that carry material energy. Of the variety of qualitative innovations in optical technology realized by nanophotonics, this books focuses on fabrication. To fabricate nano-scale photonic devices with nanometer-scale controllability in size and position, we developed a self-assembly method for size- and position-controlled ultra-long nanodot chains using a novel effect of near-field optical desorption. A novel deposition and etching scheme under nonresonant conditions is also demonstrated and its origin is reviewed.

  17. Thermal conductivity and nanocrystalline structure of platinum deposited by focused ion beam

    International Nuclear Information System (INIS)

    Pt deposited by focused ion beam (FIB) is a common material used for attachment of nanosamples, repair of integrated circuits, and synthesis of nanostructures. Despite its common use little information is available on its thermal properties. In this work, Pt deposited by FIB is characterized thermally, structurally, and chemically. Its thermal conductivity is found to be substantially lower than the bulk value of Pt, 7.2 W m−1 K−1 versus 71.6 W m−1 K−1 at room temperature. The low thermal conductivity is attributed to the nanostructure of the material and its chemical composition. Pt deposited by FIB is shown, via aberration corrected TEM, to be a segregated mix of nanocrystalline Pt and amorphous C with Ga and O impurities. Ga impurities mainly reside in the Pt while O is homogeneously distributed throughout. The Ga impurity, small grain size of the Pt, and the amorphous carbon between grains are the cause for the low thermal conductivity of this material. Since Pt deposited by FIB is a common material for affixing samples, this information can be used to assess systematic errors in thermal characterization of different nanosamples. This application is also demonstrated by thermal characterization of two carbon nanofibers and a correction using the reported thermal properties of the Pt deposited by FIB. (paper)

  18. Spatial chemistry evolution during focused electron beam-induced deposition: origins and workarounds

    International Nuclear Information System (INIS)

    The successful application of functional nanostructures, fabricated via focused electron-beam-induced deposition (FEBID), is known to depend crucially on its chemistry as FEBID tends to strong incorporation of carbon. Hence, it is essential to understand the underlying mechanisms which finally determine the elemental composition after fabrication. In this study we focus on these processes from a fundamental point of view by means of (1) varying electron emission on the deposit surface; and (2) changing replenishment mechanism, both driven by the growing deposit itself. First, we revisit previous results concerning chemical variations in nanopillars (with a quasi-1D footprint) depending on the process parameters. In a second step we expand the investigations to deposits with a 3D footprint which are more relevant in the context of applications. Then, we demonstrate how technical setups and directional gas fluxes influence final chemistries. Finally, we put the findings in a bigger context with respect to functionalities which demonstrates the crucial importance of carefully set up fabrication processes to achieve controllable, predictable and reproducible chemistries for FEBID deposits as a key element for industrially oriented applications. (orig.)

  19. Electrochemical impedance spectroscopy on nanostructured carbon electrodes grown by supersonic cluster beam deposition

    Energy Technology Data Exchange (ETDEWEB)

    Bettini, Luca Giacomo; Bardizza, Giorgio; Podesta, Alessandro; Milani, Paolo; Piseri, Paolo, E-mail: piseri@mi.infn.it [Universita degli Studi di Milano, Dipartimento di Fisica and CIMaINa (Italy)

    2013-02-15

    Nanostructured porous films of carbon with density of about 0.5 g/cm{sup 3} and 200 nm thickness were deposited at room temperature by supersonic cluster beam deposition (SCBD) from carbon clusters formed in the gas phase. Carbon film surface topography, determined by atomic force microscopy, reveals a surface roughness of 16 nm and a granular morphology arising from the low kinetic energy ballistic deposition regime. The material is characterized by a highly disordered carbon structure with predominant sp2 hybridization as evidenced by Raman spectroscopy. The interface properties of nanostructured carbon electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy employing KOH 1 M solution as aqueous electrolyte. An increase of the double layer capacitance is observed when the electrodes are heat treated in air or when a nanostructured nickel layer deposited by SCBD on top of a sputter deposited film of the same metal is employed as a current collector instead of a plain metallic film. This enhancement is consistent with an improved charge injection in the active material and is ascribed to the modification of the electrical contact at the interface between the carbon and the metal current collector. Specific capacitance values up to 120 F/g have been measured for the electrodes with nanostructured metal/carbon interface.

  20. Thermal conductivity and nanocrystalline structure of platinum deposited by focused ion beam

    KAUST Repository

    Alaie, Seyedhamidreza

    2015-02-04

    Pt deposited by focused ion beam (FIB) is a common material used for attachment of nanosamples, repair of integrated circuits, and synthesis of nanostructures. Despite its common use little information is available on its thermal properties. In this work, Pt deposited by FIB is characterized thermally, structurally, and chemically. Its thermal conductivity is found to be substantially lower than the bulk value of Pt, 7.2 W m-1 K-1 versus 71.6 W m-1 K-1 at room temperature. The low thermal conductivity is attributed to the nanostructure of the material and its chemical composition. Pt deposited by FIB is shown, via aberration corrected TEM, to be a segregated mix of nanocrystalline Pt and amorphous C with Ga and O impurities. Ga impurities mainly reside in the Pt while O is homogeneously distributed throughout. The Ga impurity, small grain size of the Pt, and the amorphous carbon between grains are the cause for the low thermal conductivity of this material. Since Pt deposited by FIB is a common material for affixing samples, this information can be used to assess systematic errors in thermal characterization of different nanosamples. This application is also demonstrated by thermal characterization of two carbon nanofibers and a correction using the reported thermal properties of the Pt deposited by FIB.

  1. Beaconless adaptive-optics technique for HEL beam control

    Science.gov (United States)

    Khizhnyak, Anatoliy; Markov, Vladimir

    2016-05-01

    Effective performance of forthcoming laser systems capable of power delivery on a distant target requires an adaptive optics system to correct atmospheric perturbations on the laser beam. The turbulence-induced effects are responsible for beam wobbling, wandering, and intensity scintillation, resulting in degradation of the beam quality and power density on the target. Adaptive optics methods are used to compensate for these negative effects. In its turn, operation of the AOS system requires a reference wave that can be generated by the beacon on the target. This report discusses a beaconless approach for wavefront correction with its performance based on the detection of the target-scattered light. Postprocessing of the beacon-generated light field enables retrieval and detailed characterization of the turbulence-perturbed wavefront -data that is essential to control the adaptive optics module of a high-power laser system.

  2. A comparison of nodular defect seed geometeries from different deposition techniques

    International Nuclear Information System (INIS)

    A focused ion-beam milling instrument commonly utilized in the semiconductor industry for failure analysis and IC repair, is capable of cross-sectioning nodular defects. Utilizing the instrument's scanning on beam, high-resolution imaging of the seeds that initiate nodular defect growth is possible. In an attempt to understand the origins of these seeds, HfO2/SiO2 and Ta2O5/SiO2 coatings were prepared by a variety of coating vendors and different deposition processes including e-beam, magnetron sputtering, and ion beam sputtering. By studying the shape, depth, and composition of the seed, inferences of its origin can be drawn. The boundaries between the nodule and thin film provide insight into the mechanical stability of the nodule. Significant differences in the seed composition, geometry of nodular growth and mechanical stability of the defects for sputtered versus e-beam coatings are reported. Differences in seed shape were also observed from different coating vendors using e-beam deposition of HfO2/SiO2 coatings

  3. Ion beam assisted deposition of nano-structured C:Ni films

    International Nuclear Information System (INIS)

    Nanostructures influence material properties dramatically due to size, shape and interface effects. Thus the control of the structure at the nanoscale is a key issue in nanomaterials science. The interaction of hyperthermal ions with solids is confined to the nanometer scale. Thus, it can be used to control the morphology evolution during multiphase film deposition. Ion-induced displacements occur in a thin surface layer of the growing film where they increase the atomic mobility for the phase separation. Here the growth-structure relationship of C:Ni (15 at.%) nanocomposite films grown by oblique incidence (45 ) ion beam assisted deposition is reported. The influences of the flux of an assisting Ar+ ion beam (0-140 eV) as well as of an elevated substrate temperature have been studied. The formation of elongated nickel nanoparticles is strongly promoted by the ion beam assistance. Moreover, the metal nanocolumns no longer align with the advancing surface, but with the incoming ions. A window of conditions is established within which the ion assistance leads to the formation of regular composition modulations with a well defined periodicity and tilt. As the dominating driving force for the pattern formation is of physical origin, this approach might be applicable to other immiscible systems.

  4. Energy distribution of secondary particles in ion beam deposition process of Ag: experiment, calculation and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Bundesmann, C.; Feder, R.; Lautenschlaeger, T.; Neumann, H. [Leibniz-Institute of Surface Modification, Leipzig (Germany)

    2015-12-15

    Ion beam sputter deposition allows tailoring the properties of the film-forming, secondary particles (sputtered target particles and backscattered primary particles) and, hence, thin film properties by changing ion beam (ion energy, ion species) and geometrical parameters (ion incidence angle, polar emission angle). In particular, the energy distribution of secondary particles and their influence on the ion beam deposition process of Ag was studied in dependence on process parameters. Energy-selective mass spectrometry was used to measure the energy distribution of sputtered and backscattered ions. The energy distribution of the sputtered particles shows, in accordance with theory, a maximum at low energy and an E{sup -2} decay for energies above the maximum. If the sum of incidence angle and polar emission angle is larger than 90 , additional contributions due to direct sputtering events occur. The energy distribution of the backscattered primary particles can show contributions by scattering at target particles and at implanted primary particles. The occurrence of these contributions depends again strongly on the scattering geometry but also on the primary ion species. The energy of directly sputtered and backscattered particles was calculated using equations based on simple two-particle-interaction whereas the energy distribution was simulated using the well-known Monte Carlo code TRIM.SP. In principal, the calculation and simulation data agree well with the experimental findings. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Thin film cadmium telluride solar cells by two chemical vapor deposition techniques

    Energy Technology Data Exchange (ETDEWEB)

    Chu, T.L.

    1988-01-15

    Cadmium telluride (CdTe) has long been recognized as a promising thin film photovoltaic material. In this work, polycrystalline p-CdTe films have been deposited by two chemical vapor deposition techniques, namely the combination of vapors of elements (CVE) and close-spaced sublimation (CSS). The CVE technique is more flexible in controlling the composition of deposited films while the CSS technique can provide very high deposition rates. The resistivity of p-CdTe films deposited by the CVE and CSS techniques can be controlled by intrinsic (cadmium vacancies) or extrinsic (arsenic or antimony) doping, and the lowest resistivity obtainable is about 200 ..cap omega.. cm. Both front-wall (CdTe/TCS/glass) and back-wall (TCS/CdTe/substrate) cells have been prepared. The back-wall cells are less efficient because of the high and irreproducible p-CdTe-substrate interface resistance. The CSS technique is superior to the CVE technique because of its simplicity and high deposition rates; however, the cleaning of the substrate in situ is more difficult. The interface cleanliness is an important factor determining the electrical and photovoltaic characteristics of the heterojunction. Heterojunction CdS/CdTe solar cells of area 1 cm/sup 2/ with conversion efficiencies higher than 10% have been prepared and junction properties characterized.

  6. Emulsion Cloud Chamber technique to measure the fragmentation of a high-energy carbon beam

    OpenAIRE

    De Lellis, G.; Buontempo., S; Di Capua, F.; Marotta, A; Migliozzi, P.; Petukhov, Y.; Pistillo, C; Russo, A; Lavina, L. Scotto; Strolin, P.(Dipartimento di Fisica dell’Università Federico II di Napoli, 80125 , Naples, Italy); Tioukov, V.; Ariga, A.(Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, CH-3012, Bern, Switzerland); Naganawa, N.; Toshito, T.; Furusawa, Y.

    2007-01-01

    Beams of Carbon nuclei are used or planned to be used in various centers for cancer treatment around the world because of their therapeutic advantages over proton beams. The knowledge of the fragmentation of Carbon nuclei when they interact with the human body is important to evaluate the spatial profile of their energy deposition in the tissues, hence the damage to the tissues neighboring the tumor. In this respect, the identification of the fragmentation products is a key element. We presen...

  7. Damage identification in beams by a response surface based technique

    Directory of Open Access Journals (Sweden)

    Teidj S.

    2014-01-01

    Full Text Available In this work, identification of damage in uniform homogeneous metallic beams was considered through the propagation of non dispersive elastic torsional waves. The proposed damage detection procedure consisted of the following sequence. Giving a localized torque excitation, having the form of a short half-sine pulse, the first step was calculating the transient solution of the resulting torsional wave. This torque could be generated in practice by means of asymmetric laser irradiation of the beam surface. Then, a localized defect assumed to be characterized by an abrupt reduction of beam section area with a given height and extent was placed at a known location of the beam. Next, the response in terms of transverse section rotation rate was obtained for a point situated afterwards the defect, where the sensor was positioned. This last could utilize in practice the concept of laser vibrometry. A parametric study has been conducted after that by using a full factorial design of experiments table and numerical simulations based on a finite difference characteristic scheme. This has enabled the derivation of a response surface model that was shown to represent adequately the response of the system in terms of the following factors: defect extent and severity. The final step was performing the inverse problem solution in order to identify the defect characteristics by using measurement.

  8. Note: Large area deposition of Rh single and Rh/W/Cu multilayer thin films on stainless steel substrate by pulsed laser deposition technique

    International Nuclear Information System (INIS)

    Mirror like thin films of single layer Rh and multilayer Rh/W/Cu are deposited on highly polished 50 mm diameter stainless steel substrate by Pulsed Laser Deposition (PLD) technique for first mirror application in fusion reactors. For this, the conventional PLD technique has been modified by incorporating substrate rastering stage for large area deposition via PLD. Process optimization to achieve uniformity of deposition as estimated from fringe visibility and thickness is also discussed

  9. New trends on deep exploration technique research of hydrothermal-type uranium deposits in southern China

    International Nuclear Information System (INIS)

    The regional and local scale metallogenic regularity is the core content in the study of deep exploration technique of hydrothermal uranium deposit in southern China. This paper connected these rules with the evaluation of prospecting potential, and explored the potential deposits and prospecting efficiency according to the geological, geophysical, geochemical characteristic data. Several innovative research results which should enhance the prediction accuracy of deep blind deposits were gained on the aspects of tectonic-controlling regularity, characteristics of metallogenic dynamics, mineralized zoning, occurrence of industrial orebody and synthetical forecasting technique. (authors)

  10. External beam radiation therapy and retinoblastoma: Long-term results in the comparison of two techniques

    International Nuclear Information System (INIS)

    Purpose: This study compares the long-term actuarial local control, eye conservation rate, survival, and ocular complications in children with retinoblastoma treated with two different external beam treatment techniques. Methods and Materials: From 1979-1991, 182 eyes in 123 children (104 bilateral) received primary external beam radiation therapy. An anterior lens-sparing electron beam technique delivering 38 to 50 Gy in 2.5 Gy fractions was used in 67 eyes from 1979-1984 and a modified lateral beam technique, delivering 42 to 46 Gy in 2 Gy fractions, was used in 113 eyes from 1984-1991. These groups were balanced with respect to known prognostic variables. Results: For Group I-III eyes, the 5- and 8-year local control was significantly improved using the modified lateral beam technique (84%) compared to (38%) using the anterior lens sparing technique (p p ≤ 0.0001). For Group IV-V eyes, the 5- and 8-year local control rates were not statistically different, despite a trend favoring the modified lateral beam technique. Survival endpoints including eye survival (no enucleation), cause-specific survival, and overall survival comparing the two treatment techniques were not significantly different. Overall, 22% of eyes developed cataracts. There was no difference between the two treatment groups in terms of cataract development. No eyes required enucleation for ocular complications. Conclusion: There is a significant improvement in local control using the modified lateral beam technique compared to an anterior lens-sparing approach for Group I-III eyes. However, there was no difference in survival end points between the two treatment techniques. The incidence of ocular complications using these two external beam techniques is acceptable.

  11. Effect of e-beam irradiation on graphene layer grown by chemical vapor deposition

    International Nuclear Information System (INIS)

    We have grown graphene by chemical vapor deposition (CVD) and transferred it onto Si/SiO2 substrates to make tens of micron scale devices for Raman spectroscopy study. The effect of electron beam (e-beam) irradiation of various doses (600 to 12 000 μC/cm2) on CVD grown graphene has been examined by using Raman spectroscopy. It is found that the radiation exposures result in the appearance of the strong disorder D band attributed the damage to the lattice. The evolution of peak frequencies, intensities, and widths of the main Raman bands of CVD graphene is analyzed as a function of defect created by e-beam irradiation. Especially, the D and G peak evolution with increasing radiation dose follows the amorphization trajectory, which suggests transformation of graphene to the nanocrystalline and then to amorphous form. We have also estimated the strain induced by e-beam irradiation in CVD graphene. These results obtained for CVD graphene are in line with previous findings reported for the mechanically exfoliated graphene [D. Teweldebrhan and A. A. Balandin, Appl. Phys. Lett. 94, 013101 (2009)]. The results have important implications for CVD graphene characterization and device fabrication, which rely on the electron microscopy.

  12. Deposition techniques for the preparation of thin film nuclear targets

    International Nuclear Information System (INIS)

    This review commences with a brief description of the basic principles that regulate vacuum evaporation and the physical processes involved in thin film formation, followed by a description of the experimental methods used. The principle methods of heating the evaporant are detailed and the means of measuring and controlling the film thickness are elucidated. Types of thin film nuclear targets are considered and various film release agents are listed. Thin film nuclear target behaviour under ion-bombardment is described and the dependence of nuclear experimental results upon target thickness and uniformity is outlined. Special problems associated with preparing suitable targets for lifetime measurements are discussed. The causes of stripper-foil thickening and breaking under heavy-ion bombardment are considered. A comparison is made between foils manufactured by a glow discharge process and those produced by vacuum sublimation. Consideration is given to the methods of carbon stripper-foil manufacture and to the characteristics of stripper-foil lifetimes are considered. Techniques are described that have been developed for the fabrication of special targets, both from natural and isotopically enriched material, and also of elements that are either chemically unstable, or thermally unstable under irradiation. The reduction of metal oxides by the use of hydrogen or by utilising a metallothermic technique, and the simultaneous evaporation of reduced rare earth elements is described. A comprehensive list of the common targets is presented

  13. The role of electron-stimulated desorption in focused electron beam induced deposition

    DEFF Research Database (Denmark)

    van Dorp, Willem F.; Hansen, Thomas Willum; Wagner, Jakob Birkedal;

    2013-01-01

    We present the results of our study about the deposition rate of focused electron beam induced processing (FEBIP) as a function of the substrate temperature with the substrate being an electron-transparent amorphous carbon membrane. When W(CO)6 is used as a precursor it is observed that the growth...... experiments compared to literature values is consistent with earlier findings by other authors. The discrepancy is attributed to electron-stimulated desorption, which is known to occur during electron irradiation. The data suggest that, of the W(CO)6 molecules that are affected by the electron irradiation......, the majority desorbs from the surface rather than dissociates to contribute to the deposit. It is important to take this into account during FEBIP experiments, for instance when determining fundamental process parameters such as the activation energy for desorption....

  14. Nanomanufacturing of titania interfaces with controlled structural and functional properties by supersonic cluster beam deposition

    Energy Technology Data Exchange (ETDEWEB)

    Podestà, Alessandro, E-mail: alessandro.podesta@mi.infn.it, E-mail: pmilani@mi.infn.it; Borghi, Francesca; Indrieri, Marco; Bovio, Simone; Piazzoni, Claudio; Milani, Paolo, E-mail: alessandro.podesta@mi.infn.it, E-mail: pmilani@mi.infn.it [Centro Interdisciplinare Materiali e Interfacce Nanostrutturati (C.I.Ma.I.Na.), Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)

    2015-12-21

    Great emphasis is placed on the development of integrated approaches for the synthesis and the characterization of ad hoc nanostructured platforms, to be used as templates with controlled morphology and chemical properties for the investigation of specific phenomena of great relevance in interdisciplinary fields such as biotechnology, medicine, and advanced materials. Here, we discuss the crucial role and the advantages of thin film deposition strategies based on cluster-assembling from supersonic cluster beams. We select cluster-assembled nanostructured titania (ns-TiO{sub 2}) as a case study to demonstrate that accurate control over morphological parameters can be routinely achieved, and consequently, over several relevant interfacial properties and phenomena, like surface charging in a liquid electrolyte, and proteins and nanoparticles adsorption. In particular, we show that the very good control of nanoscale morphology is obtained by taking advantage of simple scaling laws governing the ballistic deposition regime of low-energy, mass-dispersed clusters with reduced surface mobility.

  15. Influence of laser power on deposition of the chromium atomic beam in laser standing wave

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    One-dimensional deposition of collimated Cr atomic beam focused by a near-resonant Gaussian standing-laser field with wavelength of 425.55 nm is examined from particle-optics approach by using an adaptive step size,fourth-order Runge-Kutta type algorithm.The influence of laser power on deposition of atoms in laser standing wave is discussed and the simulative result shows that the FWHM of nanometer stripe is 102 nm and contrast is 2:1 with laser power equal to 3 mW,the FWHM is 1.2 nm and contrast is 32:1 with laser power equal to 16 mW,but with laser power increase,equal to 50 mW,the nonmeter structure forms the multi-crests and exacerbates.

  16. Antibacterial and corrosion resistance of TiN/Ag multilayers by ion beam assisted deposition

    International Nuclear Information System (INIS)

    TiN/Ag multilayers were deposited on medical stainless steel 317L by ion beam assisted deposition (IBAD). Standard agar dilution method was used to test antibacterial ratio using E.coil and S.aureus. Electro-chemical method was used to test corrosion resistance of the film in Hank's simulated human plasma. The structure and depth profile of the elements were investigated by XPS, XRD and ALES. The results show that a strong antibacterial ratio (>99%) can be obtained when the modulation period of TiN/Ag multilayers is 8 nm (5 nm TiN and 3 nm Ag). Its corrosion resistance is better than medical stainless steel 317L, approaching monolayer TiN. (authors)

  17. Ion beam sputter deposition of V 2O 5 thin films

    Science.gov (United States)

    Gallasch, T.; Stockhoff, T.; Baither, D.; Schmitz, G.

    V 2O 5 thin films were deposited by means of dc-ion beam sputtering. To determine the influence of various deposition parameters, samples were characterized by X-ray diffractometry and transmission electron microscopy. Using electron energy loss spectroscopy, the oxidation state of vanadium was quantified based on the chemical shift of absorption edges. Measurement of in-plane direct current showed that the electronic conductivity varies over several orders of magnitude depending on the preparation conditions. The desired structure suitable for battery applications is achieved by sputtering under partial pressure of oxygen and suitable post-annealing under ambient atmosphere. Reversible intercalation of Li into the produced thin films was demonstrated.

  18. Nanomanufacturing of titania interfaces with controlled structural and functional properties by supersonic cluster beam deposition

    International Nuclear Information System (INIS)

    Great emphasis is placed on the development of integrated approaches for the synthesis and the characterization of ad hoc nanostructured platforms, to be used as templates with controlled morphology and chemical properties for the investigation of specific phenomena of great relevance in interdisciplinary fields such as biotechnology, medicine, and advanced materials. Here, we discuss the crucial role and the advantages of thin film deposition strategies based on cluster-assembling from supersonic cluster beams. We select cluster-assembled nanostructured titania (ns-TiO2) as a case study to demonstrate that accurate control over morphological parameters can be routinely achieved, and consequently, over several relevant interfacial properties and phenomena, like surface charging in a liquid electrolyte, and proteins and nanoparticles adsorption. In particular, we show that the very good control of nanoscale morphology is obtained by taking advantage of simple scaling laws governing the ballistic deposition regime of low-energy, mass-dispersed clusters with reduced surface mobility

  19. Mechanical properties of silicon oxynitride thin films prepared by low energy ion beam assisted deposition

    International Nuclear Information System (INIS)

    Silicon oxynitride (SiOxNy) films (0.1-0.7 μm) were produced on Si (1 0 0), glass and 316L stainless steel substrates by ion beam assisted deposition (IBAD) using Si evaporation and the concurrent bombardment with a mixture of 200 eV N2 and Ar, or O2 and Ar ions. Adhesion was evaluated by pull-off tests. Film hardness was measured by a nanoindentation system with AFM. The measurement of internal stress in the films was carried out by the Stoney method. The film structure was examined by GXRD. XPS was employed to measure the composition of films and to analyze the chemical bonds. The dependence of mechanical properties on the film thickness and the processing temperature during deposition was studied. Finally, the relations between the mechanical properties of the films and the correlation with corrosion-protection ability of films are discussed and summarized

  20. Mechanical properties of silicon oxynitride thin films prepared by low energy ion beam assisted deposition

    Science.gov (United States)

    Shima, Yukari; Hasuyama, Hiroki; Kondoh, Toshiharu; Imaoka, Yasuo; Watari, Takanori; Baba, Koumei; Hatada, Ruriko

    1999-01-01

    Silicon oxynitride (SiO xN y) films (0.1-0.7 μm) were produced on Si (1 0 0), glass and 316L stainless steel substrates by ion beam assisted deposition (IBAD) using Si evaporation and the concurrent bombardment with a mixture of 200 eV N 2 and Ar, or O 2 and Ar ions. Adhesion was evaluated by pull-off tests. Film hardness was measured by a nanoindentation system with AFM. The measurement of internal stress in the films was carried out by the Stoney method. The film structure was examined by GXRD. XPS was employed to measure the composition of films and to analyze the chemical bonds. The dependence of mechanical properties on the film thickness and the processing temperature during deposition was studied. Finally, the relations between the mechanical properties of the films and the correlation with corrosion-protection ability of films are discussed and summarized.

  1. Optimization of Energy Scope for Titanium Nitride Films Grown by Ion Beam-Assisted Deposition

    Institute of Scientific and Technical Information of China (English)

    LI Wei; MA Zhong-Quan; WANG Ye; WANG De-Ming

    2006-01-01

    The deposited energy during film growth with ion bombardment, correlated to the atomic displacement on the surface monolayer and the underlying bulk, has been calculated by a simplified ion-solid interaction model under binary collision approximation. The separated damage energies caused by Ar ion, different for the surface and the bulk, have been determined under the standard collision cross section and a well-defined surface and bulk atom displacement threshold energy of titanium nitride (TiN). The optimum energy scope shows that the incident energy of Ar+ around 110eV for TiN (111) and 80eV for TiN (200) effectively enhances the mobility of adatom on surface but excludes the damage in underlying bulk. The theoretical prediction and the experimental result are in good agreement in low energy ion beam-assisted deposition.

  2. Electroluminescence and its excitation mechanism of SiOx films deposited by electron-beam evaporation

    International Nuclear Information System (INIS)

    Blue electroluminescence from SiOx films deposited by electron beam evaporation was observed. This blue emission blueshifted from 450 to 410 nm with increasing applied voltage. The dependences of blue emission on applied voltage, frequency and conduction current were studied. Our experimental data support that blue emission from SiOx films is the result of both recombination of charge carriers injected from opposite electrodes and impact excitation of hot electrons, the recombination of carriers injected is dominant in low and medium electric fields but hot electron impact excitation is dominant under high electric fields

  3. Energy deposition in selected-mammalian cell for several-MeV single-proton beam

    Science.gov (United States)

    Ding, K.; Yu, Z.

    2007-05-01

    The phenomena resulting from interaction between ion beam and mammalian cell pose important problems for biological applications. Classic Bethe-Bloch theory utilizing attached V79 mammalian cell has been conducted in order to establish the stopping powers of the mammalian cell for several-MeV single-proton microbeam. Based on the biological structure of the mammalian cell, a physical model is proposed which presumes that the attached cell is simple MWM model. According to this model and Monte Carlo simulation, we studied the energy deposition and its ratio on the selected attached mammalian cell for MeV proton implantation.

  4. Analyses of the microstructures of Si3N4 film by ion beam enhanced deposition

    International Nuclear Information System (INIS)

    TEM, SEM and X-ray have been used to investigate the microstructures of the silicon ntiride film by Ion Beam Enhanced Deposition (IBED) on surface of 1 Cr19Ni9Ti. Observation reveals that Si3N4 is the amorphous structure and have a little dispersed single crystal phase β-Si3N4 in the film. The physiognomy of Si3N4, interface shape of Si3N4/1Cr18Ni9Ti and the factors influencing on the formation were discussed

  5. Dispersive ground plane core-shell type optical monopole antennas fabricated with electron beam induced deposition.

    Science.gov (United States)

    Acar, Hakkı; Coenen, Toon; Polman, Albert; Kuipers, Laurens Kobus

    2012-09-25

    We present the bottom-up fabrication of dispersive silica core, gold cladding ground plane optical nanoantennas. The structures are made by a combination of electron-beam induced deposition of silica and sputtering of gold. The antenna lengths range from 300 to 2100 nm with size aspect ratios as large as 20. The angular emission patterns of the nanoantennas are measured with angle-resolved cathodoluminescence spectroscopy and compared with finite-element methods. Good overall correspondence between the the measured and calculated trends is observed. The dispersive nature of these plasmonic monopole antennas makes their radiation profile highly tunable. PMID:22889269

  6. Applied dosimetry to ionization techniques by electron beams

    International Nuclear Information System (INIS)

    After a general introduction about electron beam dosimetry, the second part is about the determination of treatment parameter for an electron ionization: are treated the problems of electron path determination, treatment depth of a product and finally, the radiation dose heterogeneities in all the volume of a treated product. The third part describes a process that greatly reduces radiation dose heterogeneity and then industrial interest is analyzed. The fourth part describes 2 applications of diffusion screen utilization. 66 figs

  7. Atomic layer deposition of an Al2O3 dielectric on ultrathin graphite by using electron beam irradiation

    Institute of Scientific and Technical Information of China (English)

    Jiang Ran; Meng Lingguo; Zhang Xijian; Hyung-Suk Jung; Cheol Seong Hwang

    2012-01-01

    Atomic layer deposition ofan Al2O3 dielectric on ultrathin graphite is studied in order to investigate the integration of a high k dielectric with graphite-based substrates.Electron beam irradiation on the graphite surface is followed by a standard atomic layer deposition of Al2O3.Improvement of the Al2O3 layer deposition morphology was observed when using this radiation exposure on graphite.This result may be attributed to the amorphous change of the graphite layers during electron beam irradiation.

  8. Beam steering laser assisted deposition system for high-Tc superconducting thin film devices

    International Nuclear Information System (INIS)

    We present the design and construction of a beam steering laser-assisted deposition system (LAD) for high quality epitaxial YBaCuO superconducting thin film production suitable for commercial application. Deposition of single layer or multilayer YBaCuO superconducting thin film on large and complex surfaced substrate is now feasible. Expitaxial and polycrystaline films with onsets at 90 K having 6 K transition widths have been produced. Dome-shaped magnetic shield enclosures, microwave cavity resonant in the TM010 mode, and short dipole antennas have been fabricated. The advantages of the laser ablation deposition method [J. T. Cheung and D. T. Chueng, J. Vac. Sci. Technol. 21, 182 (1982)] are its simplicity and cleanliness. Laser ablation deposition is a viable method to produce high quality thin film of the Tl-based compound [S. H. Liou and K. D. Aylesworth, Appl. Phys. Lett. 54, 760 (1989)] by using a small target in a sealed environment which is important in handling toxic material of a Tl-based compounds

  9. Flexible, ionic liquid-based micro-supercapacitor produced by supersonic cluster beam deposition

    International Nuclear Information System (INIS)

    Highlights: • We exploited Supersonic Cluster Beam Deposition for the fabrication of a flexible, planar micro-supercapacitor featuring nanostructured carbon electrodes deposited on a plastic Mylar substrate and N-trimethyl-N-propyl-ammonium bis(trifluoromethanesulfonyl) imide (N1113TFSI) ionic liquid electrolyte. • The micro-supercapacitor operates at 3 V above RT up to 80 °C with a capacitance density approaching 10 F cm−3 and delivering maximum specific energy and power densities of 10 mWh cm−3 and 8-10 W cm−3. • The micro-supercapacitor features long cycling stability over 2x104cycle on flat and bent configuration. -- Graphical abstract: Display Omitted -- Abstract: Power generation and storage in electronics require flexible, thin micro-electrochemical energy storage/conversion systems. Micro-supercapacitors (μSCs) with double-layer capacitance carbon electrodes are attracting much attention for their capability of delivering short power pulses with high stability over repeated charge/discharge cycling. Supersonic Cluster Beam Deposition (SCBD) is an effective strategy for the development of nanostructured, binder-free porous carbon electrodes on temperature sensitive substrates including polymers. We exploited SCBD for the development of a flexible, planar μSC featuring nanostructured carbon (ns-C) electrodes deposited on a plastic Mylar substrate and N-trimethyl-N-propyl-ammonium bis(trifluoromethanesulfonyl) imide (N1113TFSI) ionic liquid electrolyte. The electrochemical performance at different temperatures of the μSC which operates at 3 V above RT up to 80 °C with a capacitance density approaching 10 F cm−3 and delivering maximum specific energy and power densities of 10 mWh cm−3 and 8-10 W cm−3 with long cycling stability over 2 × 104 cycles is here reported and discussed

  10. Beam manipulation techniques, nonlinear beam dynamics, and space charge effect in high energy high power accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S. Y.

    2014-04-07

    We had carried out a design of an ultimate storage ring with beam emittance less than 10 picometer for the feasibility of coherent light source at X-ray wavelength. The accelerator has an inherent small dynamic aperture. We study method to improve the dynamic aperture and collective instability for an ultimate storage ring. Beam measurement and accelerator modeling are an integral part of accelerator physics. We develop the independent component analysis (ICA) and the orbit response matrix method for improving accelerator reliability and performance. In collaboration with scientists in National Laboratories, we also carry out experimental and theoretical studies on beam dynamics. Our proposed research topics are relevant to nuclear and particle physics using high brightness particle and photon beams.

  11. Mechanical properties and thermal stability of TiAlN/Ta multilayer film deposited by ion beam assisted deposition

    International Nuclear Information System (INIS)

    Highlights: • Nanohardness of the TiAlN/Ta multilayer film was 29% higher than that of the TiAlN monolayer film. • Compared to the TiAlN monolayer film, a 47% increase of elastic modulus was achieved. • Bonding strength of the TiAlN/Ta multilayer film was higher than that of the TiAlN monolayer film. • The TiAlN/Ta multilayer film has better thermal stability than the TiAlN monolayer film. - Abstract: TiAlN/Ta multilayer film with the total thickness of 2 μm was deposited onto silicon (1 0 0) wafer by ion beam assisted deposition using Ti0.5Al0.5 and Ta as the target materials. Observation of the cross-sectional microstructure and XRD pattern showed that the Ta sub-layer restrained the growth of TiAlN crystal, and decreased the grain size. Nanohardness (H) of the TiAlN/Ta multilayer film was 29% higher and the elastic modulus (E) was 47% higher than that of the TiAlN monolayer film. The critical fracture load (Lc) of 72 mN for the TiAlN/Ta multilayer film was achieved, much higher than that of the monolayer TiAlN film (30 mN), indicated a significant increase of bonding strength. Results of DSC analysis indicated that the TiAlN/Ta multilayer film had the exothermic peak at around 935 °C, 75 °C above that for the TiAlN monolayer film. Existence of the Ta sub-layers behaved as the barrier layers to prevent oxygen from diffusing into inner layers, resulted in the improvement of thermal stability

  12. Infrared and ion beam analysis of SI/sub x/N/sub 1-x/ alloys grown by ion beam assisted deposition

    International Nuclear Information System (INIS)

    Thin films of amorphous Si/sub x/N/sub 1-x/ alloys were produced by nitrogen ion beam assisted deposition of electron beam evaporated silicon. Infrared reflection spectra were measured in the range 600 to 10000 cm/sup -1/. Fringes were observed due to interference between light multiply-reflected from the front surface and film-substrate (single crystal silicon) interface. Similar measurements were performed on films crystallized by post-deposition furnace anneals. Analyses of the reflection spectra were used to obtain refractive index profiles. Profiles were correlated with nitrogen content as measured by Rutherford Backscattering Spectometry (RBS) and Auger Electron Spectroscopy (AES). Film adhesion, density, and purity were found to be improved for depositions assisted by nitrogen ion beams (1000 to 25,000 eV) relative to unassisted evaporation, and the index of refraction decreases monotonically with increasing nitrogen content

  13. Reinforced concrete beams strengthened with carbon fiber reinforced polymer by friction hybrid bond technique: Experimental investigation

    International Nuclear Information System (INIS)

    Highlights: • Friction Hybrid Bonded FRP Technique is conducted to strengthen RC beams. • Six specimens with different reinforced methods were tested. • The strengthened effects of different strengthening methods were discussed. • The results obtained from the FEA and experiments are agreed very well. - Abstract: Carbon fiber reinforced polymer (CFRP) can be used to strengthen the reinforced concrete (RC) beams. But premature debonding is the main failure model in ordinary bond technique, and the strengthening effect is limited. In order to improve bonding and restricting sliding displacement, Friction Hybrid Bonded FRP Technique (FHB-FRP) is developed. Six simple-span RC specimen beams with different strengthened methods were tested in four-point bending. The experiment results indicate that FRP debonding can be effectively prevented by the FHB-FRP strengthened beam. The ultimate load-carrying capacity of the specimen strengthened by FHB-FRP technique is able to increase by a factor of 2.13 times compared with the beam strengthened with ordinary bond technique (U-jacketing technique). In addition, the cracking and yielding loads are improved more significantly by FHB-FRP technique than U-jacketing technique. Specimens strengthened with FHB-FRP technique have cracks with a more limited distribution and width. Finally, the finite element method (FEM) is conducted to simulate the behavior of the test specimens. The results obtained from the finite element method are compared with experiment. Excellent agreements have been achieved in the comparison of results

  14. Structural changes of electron and ion beam-deposited contacts in annealed carbon-based electrical devices

    KAUST Repository

    Batra, Nitin M

    2015-10-09

    The use of electron and ion beam deposition to make devices containing discrete nanostructures as interconnectors is a well-known nanofabrication process. Classically, one-dimensional materials such as carbon nanotubes (CNTs) have been electrically characterized by resorting to these beam deposition methods. While much attention has been given to the interconnectors, less is known about the contacting electrodes (or leads). In particular, the structure and chemistry of the electrode–interconnector interface is a topic that deserves more attention, as it is critical to understand the device behavior. Here, the structure and chemistry of Pt electrodes, deposited either with electron or ion beams and contacted to a CNT, are analyzed before and after thermally annealing the device in a vacuum. Free-standing Pt nanorods, acting as beam-deposited electrode models, are also characterized pre- and post-annealing. Overall, the as-deposited leads contain a non-negligible amount of amorphous carbon that is consolidated, upon heating, as a partially graphitized outer shell enveloping a Pt core. This observation raises pertinent questions regarding the definition of electrode–nanostructure interfaces in electrical devices, in particular long-standing assumptions of metal-CNT contacts fabricated by direct beam deposition methods.

  15. Structural changes of electron and ion beam-deposited contacts in annealed carbon-based electrical devices

    Science.gov (United States)

    Batra, Nitin M.; Patole, Shashikant P.; Abdelkader, Ahmed; Anjum, Dalaver H.; Deepak, Francis L.; Costa, Pedro M. F. J.

    2015-11-01

    The use of electron and ion beam deposition to make devices containing discrete nanostructures as interconnectors is a well-known nanofabrication process. Classically, one-dimensional materials such as carbon nanotubes (CNTs) have been electrically characterized by resorting to these beam deposition methods. While much attention has been given to the interconnectors, less is known about the contacting electrodes (or leads). In particular, the structure and chemistry of the electrode-interconnector interface is a topic that deserves more attention, as it is critical to understand the device behavior. Here, the structure and chemistry of Pt electrodes, deposited either with electron or ion beams and contacted to a CNT, are analyzed before and after thermally annealing the device in a vacuum. Free-standing Pt nanorods, acting as beam-deposited electrode models, are also characterized pre- and post-annealing. Overall, the as-deposited leads contain a non-negligible amount of amorphous carbon that is consolidated, upon heating, as a partially graphitized outer shell enveloping a Pt core. This observation raises pertinent questions regarding the definition of electrode-nanostructure interfaces in electrical devices, in particular long-standing assumptions of metal-CNT contacts fabricated by direct beam deposition methods.

  16. Elemental analysis of limestone samples from Obajana and Mfamosing limestone deposits, Nigeria, using nuclear techniques

    Energy Technology Data Exchange (ETDEWEB)

    Akpan, I.O. [Department of Physics, University of Calabar, Calabar, Cross River State (Nigeria); Amodu, A.E. [Science Laboratory Technology Department, Federal Polytechnic, Idah, Kogi State (Nigeria); Akpan, A.E., E-mail: anthonyakpan@yahoo.com [Department of Physics, University of Calabar, Calabar, Cross River State (Nigeria)

    2011-10-15

    Six limestone samples were picked from three different points at the Obajana and Mfamosing limestone deposits. The limestone samples were subjected to elemental analysis by Proton-Induced X-Ray Emission (PIXE) analysis. The samples were irradiated by a 4 mm diameter beam of protons with energy of 2.5 MeV and beam current of 0.2 nA for 0.9 ms. The analysis was carried out with the 1.7 MV Tandem accelerator at the Centre for Energy Research and Development (CERD), Ile-Ife, Osun State, Nigeria. The NIST geology standard NIST 278 was analysed for quality assurance. The elemental composition and concentration of 14 elements were determined in the two locations. Ten elements were found at the Obajana deposit while 13 elements were found at the Mfamosing deposits. The elements: Mg, Al, Ca and Mn do not differ much at both deposits while others differ. The major elements (Ca, Fe, Al, Si and K) present in the limestones were also found in airborne particulate matter studied by earlier researchers. These observations suggest that all particulate emissions and wastes from the Limestone deposit should be closely monitored to reduce their cumulative effects on both health and the environment

  17. Optimisation of the electroless metal deposition technique for use in photonics

    DEFF Research Database (Denmark)

    Malureanu, Radu; Andryieuski, Andrei; Lavrinenko, Andrei

    2010-01-01

    made in the last years, there is still a long way until practical implementation into everyday devices. One of the main bottlenecks, from the fabrication point of view, is the necessity for depositing silver on complex 3D structures. To our knowledge, the best result so far, was obtained using plasma...... enhanced chemical vapour deposition (PECVD) technique [5]. Even if the results are promising, the parameter space of such technique is huge thus making it almost impossible to avoid the local optimum points. In this work we present an optimised technique for 3D deposition of metals. Our technique is based...... on the well known Tollen’s test for detecting the presence of aldehyde groups inside a solution [6]. By optimising the concentration and the ratio of the chemicals involved, one can obtain very smooth and thin Ag layers (see figure 1a). In the same time, since the reaction takes place in solution, it...

  18. Experimental study on fracture behavior of pre-notched mortar beams using ESPI technique

    OpenAIRE

    Chen, H.; Su, RKL

    2011-01-01

    Electronic Speckle Pattern Interferometry (ESPI) technique is of high sensitivity and can provide full-field surface deformation. This paper introduces the application of ESPI technique to measure the surface deformation of pre-notched mortar beams in three-point bending tests. In addition to ESPI, Linear Variable Differential Transformers (LVDTs) and clip gauge extensometer were used to measure the mid-span deflection and Crack Mouth Opening Displacement (CMOD) of the beam respectively. Disp...

  19. Strengthening of RC Beams Using Externally Bonded Reinforcement Combined with Near-Surface Mounted Technique

    Directory of Open Access Journals (Sweden)

    Kh Mahfuz ud Darain

    2016-07-01

    Full Text Available This study investigates the flexural behaviour of reinforced concrete (RC beams strengthened through the combined externally bonded and near-surface mounted (CEBNSM technique. The externally bonded reinforcement (EBR and near-surface mounted (NSM techniques are popular strengthening solutions, although these methods often demonstrate premature debonding failure. The proposed CEBNSM technique increases the bond area of the concrete–carbon fibre reinforced polymer (CFRP interface, which can delay the debonding failure. This technique is appropriate when any structure has a narrow cross-sectional width or is in need of additional flexural capacity that an individual technique or material cannot attain. An experimental test matrix was designed with one control and five strengthened RC beams to verify the performance of the proposed technique. The strengthening materials were CFRP bar as NSM reinforcement combined with CFRP fabric as EBR material. The test variables were the diameter of the NSM bars (8 and 10 mm, the thickness of the CFRP fabrics (one and two layers and the U-wrap anchorage. The strengthened beams showed enhancement of ultimate load capacity, stiffness, cracking behaviour, and strain compatibility. The ultimate capacity of the CEBNSM-strengthened beams increased from 71% to 105% compared to that of the control beam. A simulation method based on the moment-rotation approach was also presented to predict the behaviour of CEBNSM-strengthened RC beams.

  20. Biaxial Texture Evolution in MgO Films Fabricated Using Ion Beam-Assisted Deposition

    Science.gov (United States)

    Xue, Yan; Zhang, Ya-Hui; Zhao, Rui-Peng; Zhang, Fei; Lu, Yu-Ming; Cai, Chuan-Bing; Xiong, Jie; Tao, Bo-Wan

    2016-04-01

    The growth of multifunctional thin films on flexible substrates is important technologically, because flexible electronics require such a platform. In this study, we examined the evolution of biaxial texture in MgO films prepared using ion beam-assisted deposition (IBAD) on a Hastelloy substrate. Texture and microstructure developments were characterized through in situ reflection high-energy electron diffraction monitoring, x-ray diffraction, and atomic force microscopy, which demonstrated that biaxial texture was developed during the nucleation stage (~2.2 nm). The best biaxial texture was obtained with a thickness of approximately 12 nm. As MgO continued to grow, the influence of surface energy was reduced, and film growth was driven by the attempt to minimize volume free-energy density. Thus the MgO grains were subsequently rotated at the (002) direction toward the ion beam. In addition, an approach was developed for accelerating in-plane texture evolution by pre-depositing an amorphous MgO layer before IBAD.

  1. Ion beam deposition of DLC and nitrogen doped DLC thin films for enhanced haemocompatibility on PTFE

    International Nuclear Information System (INIS)

    Diamond-like carbon (DLC) and N-doped DLC (DLC:N) thin films have been synthesized on polytetrafluroethylene (PTFE) and silicon wafers using ion beam deposition. Raman spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy and scanning electron microscopy were used to study the structural and morphological properties of the coated surface. The results show that the ion beam deposited DLC thin films exhibit high hardness and Young's modulus, low coefficient of friction and high adhesion to the substrate. Low concentration of nitrogen doping in DLC improves the mechanical properties and reduces the surface roughness. DLC coating decreases the surface energy and improves the wettability of PTFE. The platelet adhesion results show that the haemocompatibility of DLC coated PTFE, especially DLC:N coated PTFE, has been significantly enhanced as compared with uncoated PTFE. SEM observations show that the platelet reaction on the DLC and DLC:N coated PTFE was minimized as the platelets were much less aggregated and activated.

  2. Biaxial Texture Evolution in MgO Films Fabricated Using Ion Beam-Assisted Deposition

    Science.gov (United States)

    Xue, Yan; Zhang, Ya-Hui; Zhao, Rui-Peng; Zhang, Fei; Lu, Yu-Ming; Cai, Chuan-Bing; Xiong, Jie; Tao, Bo-Wan

    2016-07-01

    The growth of multifunctional thin films on flexible substrates is important technologically, because flexible electronics require such a platform. In this study, we examined the evolution of biaxial texture in MgO films prepared using ion beam-assisted deposition (IBAD) on a Hastelloy substrate. Texture and microstructure developments were characterized through in situ reflection high-energy electron diffraction monitoring, x-ray diffraction, and atomic force microscopy, which demonstrated that biaxial texture was developed during the nucleation stage (~2.2 nm). The best biaxial texture was obtained with a thickness of approximately 12 nm. As MgO continued to grow, the influence of surface energy was reduced, and film growth was driven by the attempt to minimize volume free-energy density. Thus the MgO grains were subsequently rotated at the (002) direction toward the ion beam. In addition, an approach was developed for accelerating in-plane texture evolution by pre-depositing an amorphous MgO layer before IBAD.

  3. Comparison between beam-stop and beam-hole array scatter correction techniques for industrial X-ray cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Schoerner, K., E-mail: karsten.schoerner.ext@siemens.co [Corporate Technology, Siemens AG, 81739 Muenchen (Germany); Physik-Department, Technische Universitaet Muenchen, 85748 Garching (Germany); Goldammer, M.; Stephan, J. [Corporate Technology, Siemens AG, 81739 Muenchen (Germany)

    2011-02-01

    Research highlights: {yields} We propose a scatter correction method employing a beam-hole array. {yields} Beam-hole and beam-stop array techniques are compared in respect of geometric and scattering properties. {yields} The beam-hole array method reduces overall scattering compared to a beam-stop array. {yields} Application of the beam-hole array method is successfully demonstrated for a CT of ceramic specimen. -- Abstract: In industrial X-ray cone-beam computed tomography, the inspection of large-scale samples is important because of increasing demands on their quality and long-term mechanical resilience. Large-scale samples, for example made of aluminum or iron, are strongly scattering X-rays. Scattered radiation leads to artifacts such as cupping, streaks, and a reduction in contrast in the reconstructed CT-volume. We propose a scatter correction method based on sampling primary signals by employing a beam-hole array (BHA). In this indirect method, a scatter estimate is calculated by subtraction of the sampled primary signal from the total signal, the latter taken from an image where the BHA is absent. This technique is considered complementary to the better known beam-stop array (BSA) method. The two scatter estimation methods are compared here with respect to geometric effects, scatter-to-total ratio and practicability. Scatter estimation with the BHA method yields more accurate scatter estimates in off-centered regions, and a lower scatter-to-total ratio in critical image regions where the primary signal is very low. Scatter correction with the proposed BHA method is then applied to a ceramic specimen from power generation technologies. In the reconstructed CT volume, cupping almost completely vanishes and contrast is enhanced significantly.

  4. A technique to sharpen the beam penumbra for Gamma Knife radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, M; Li, X Allen; Ma Lijun [Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD 21201 (United States)

    2003-06-21

    In stereotactic radiosurgery, a narrow beam penumbra is often desired for producing steep dose fall-off between the target volume and adjacent critical structures. Due to limited source sizes and the scattering effects, the physical penumbra of the Gamma Knife (GK) is often restricted to a width of 1-2 mm. In this work, we developed a technique to further reduce the beam penumbra and improve the dose profile for the Gamma Knife delivery. Under this technique, a conic filter is inserted into an individual plug collimator of a GK helmet to flatten the beam profile. Monte Carlo calculations were carried out to simulate the GK geometry of the individual plug collimator and to optimize the physical shapes of the filters. The calculations were performed for a series of filter shapes with different collimator sizes. Our results show that a proper filter significantly reduces the single GK beam penumbra width (defined as the distance from the 90% to 50% isodose lines) by 30-60%. The beam intensity is reduced by about 20-50% when the filter is used. A treatment plan was developed for a trigeminal neuralgia case by commissioning the filtered beam profile for Leksell Gamma Plan (version 5.31). Compared with the conventional treatment plan, a significant improvement was found on the critical structure sparing and on the target dose uniformity. In conclusion, the proposed technique is feasible and effective in sharpening the beam penumbra for Gamma Knife beam profiles.

  5. Some basic phenomena and their importance in relation to techniques for sputter- and vapor-deposition of high temperature superconducting thin films

    International Nuclear Information System (INIS)

    The processes involved in plasma and ion beam sputter-, electron evaporation-, and laser ablation-deposition of high Tc superconducting thin films are critically reviewed. Recent advances in the development of these techniques are discussed in relation to basic physical phenomena, specific to each technique, which must be understood before high quality films can be grown. Low temperature processing of films is a common goal for each technique, and efforts in this area using activated oxygen sources are discussed in view of integrating the high Tc superconducting thin films with current microelectronic technologies

  6. An evaluation testing technique of single event effect using Beam Blanking SEM

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, J.; Hada, T.; Pesce, A.; Akutsu, T.; Matsuda, S. [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan). Tsukuba Space Center; Igarashi, T.; Baba, S.

    1997-03-01

    Beam Blanking SEM (Scanning Electron Microscope) testing technique has been applied to CMOS SRAM devices to evaluate the occurence of soft errors on memory cells. Cross-section versus beam current and LET curves derived from BBSEM and heavy ion testing technique, respectively, have been compared. A linear relation between BBSEM current and heavy ion LET has been found. The purpose of this study was to demonstrate that the application of focused pulsed electron beam could be a reliable, convenient and inexpensive tool to investigate the effects of heavy ions and high energy particles on memory devices for space application. (author)

  7. Characterization of calcium phosphate coatings doped with Mg, deposited by pulsed laser deposition technique using ArF excimer laser.

    Science.gov (United States)

    Mróz, W; Jedyński, M; Prokopiuk, A; Slósarczyk, A; Paszkiewicz, Z

    2009-01-01

    Calcium phosphate layers were deposited on Ti6Al4V substrates with TiN buffer layers by use of pulsed laser deposition method. With this technique three pressed pellets consisted of tricalcium phosphate (TCP, Ca(3)(PO(4))(2)), hydroxyapatite (HA, Ca(10)(PO(4))(6)(OH)(2)) and hydroxyapatite-doped with magnesium (HA with 4% of Mg and trace amount of (Ca,Mg)(3)(PO(4))(2)) were ablated using ArF excimer laser (lambda=193 nm). The using of different targets enabled to determine the influence of target composition on the nature of deposited layers. The obtained deposits were characterized by means of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction method (XRD). The obtained Fourier spectras revealed differences in terms of intensity of spectral bands of different layers. The analysis from XRD showed that Mg-doped HA layer has crystalline structure and TCP and HA layers composition is characterized by amorphous nature. PMID:18407507

  8. Emulsion Cloud Chamber technique to measure the fragmentation of a high-energy carbon beam

    CERN Document Server

    De Lellis, G; Buontempo, S; Capua, F D; Furusawa, Y; Lavina, L S; Marotta, A; Migliozzi, P; Naganawa, N; Petukhov, Yu P; Pistillo, C; Russo, A; Strolin, P; Tioukov, V; Toshito, T; Yasuda, N

    2007-01-01

    Beams of Carbon nuclei are now in use or planned to be used in various centers for cancer treatment around the world. The knowledge of the fragmentation of Carbon nuclei when they interact with the human body is important for evaluating of the spatial profile of their energy deposition in the tissues, hence the damage to tissues neighbouring the tumor. To this purpose, the identification of the fragmentation products is a key element. We present in this paper the charge measurement of about 3000 fragments produced by the interaction of $^{12}$C nuclei with an energy of 400 MeV/nucleon in a detector simulating the density of the human body. The nuclear emulsion technique is used, by means of the so-called Emulsion Cloud Chamber. The nuclear emulsions are inspected using fast automated microscopes recently developed. A charge assignment efficiency of more than 99% is achieved. The separation of Hydrogen, Helium, Lithium, Berillium, Boron and Carbon can be achieved at two standard deviations or considerably more...

  9. Hybrid nanocomposite coatings from metal (Mg alloy)-drug deposited onto medical implant by laser adaptive ablation deposition technique

    Science.gov (United States)

    Serbezov, Valery; Sotirov, Sotir; Serbezov, Svetlin

    2013-03-01

    Drug-eluting medical implants are active implants whose function is to create healing effects. The current requirements for active medical coatings for Drug-eluting medical implants are to be biocompatible, biodegradable, polymer free, mechanically stable and enable a controlled release of one or more drugs and defined degradation. This brings hybrid nanocomposite coatings into focus especially in the field of cardiovascular implants. We studied the properties of Metal (Mg alloy)-Paclitaxel coatings obtained by novel Laser Adaptive Ablation Deposition Technique (LAAD) onto cardiovascular stents from 316 LVM stainless steel material. The morphology and topology of coatings were studied by Bright field / Fluorescence optical microscope and Scanning Electron Microscope (SEM). Comparative measurements were made of the morphology and topology of hybrid, polymer free nanocomposite coatings deposited by LAAD and polymerdrug coatings deposited by classical spray technique. The coatings obtained by LAAD are homogeneous without damages and cracks. Metal nanoparticles with sizes from 40 nm to 230 nm were obtained in drug matrixes. Energy Dispersive X-ray Spectroscopy (EDX) was used for identification of metal nanoparticles presence in hybrid nanocomposites coatings. The new technology opens up possibilities to obtain new hybrid nanocomposite coatings with applications in medicine, pharmacy and biochemistry.

  10. Approaching Defect-free Amorphous Silicon Nitride by Plasma-assisted Atomic Beam Deposition for High Performance Gate Dielectric.

    Science.gov (United States)

    Tsai, Shu-Ju; Wang, Chiang-Lun; Lee, Hung-Chun; Lin, Chun-Yeh; Chen, Jhih-Wei; Shiu, Hong-Wei; Chang, Lo-Yueh; Hsueh, Han-Ting; Chen, Hung-Ying; Tsai, Jyun-Yu; Lu, Ying-Hsin; Chang, Ting-Chang; Tu, Li-Wei; Teng, Hsisheng; Chen, Yi-Chun; Chen, Chia-Hao; Wu, Chung-Lin

    2016-01-01

    In the past few decades, gate insulators with a high dielectric constant (high-k dielectric) enabling a physically thick but dielectrically thin insulating layer, have been used to replace traditional SiOx insulator and to ensure continuous downscaling of Si-based transistor technology. However, due to the non-silicon derivative natures of the high-k metal oxides, transport properties in these dielectrics are still limited by various structural defects on the hetero-interfaces and inside the dielectrics. Here, we show that another insulating silicon compound, amorphous silicon nitride (a-Si3N4), is a promising candidate of effective electrical insulator for use as a high-k dielectric. We have examined a-Si3N4 deposited using the plasma-assisted atomic beam deposition (PA-ABD) technique in an ultra-high vacuum (UHV) environment and demonstrated the absence of defect-related luminescence; it was also found that the electronic structure across the a-Si3N4/Si heterojunction approaches the intrinsic limit, which exhibits large band gap energy and valence band offset. We demonstrate that charge transport properties in the metal/a-Si3N4/Si (MNS) structures approach defect-free limits with a large breakdown field and a low leakage current. Using PA-ABD, our results suggest a general strategy to markedly improve the performance of gate dielectric using a nearly defect-free insulator. PMID:27325155

  11. Ion-beam-induced epitaxial crystallization of implanted and chemical vapor deposited amorphous silicon

    Science.gov (United States)

    La Ferla, A.; Priolo, F.; Spinella, C.; Rimini, E.; Baroetto, F.; Ferla, G.

    1989-03-01

    The dependence of ion-beam enhanced epitaxial growth of amorphous Si layers on impurities either dissolved in the film or present at the film-substrate interface is considered. In the case of ion implanted layers, electrically active dopants, like B, P, As at concentrations above 1 × 10 20/cm 3, enhance the rate by a factor of 2 with respect to the undoped layer. The enhancement shows also a weak dependence on the dopant concentration. Inert impurities, like Ar, which prevent pure thermal regrowth, do not show any appreciable influence on the ion-beam-induced growth rate. Chemical vapor deposited Si layers with a thin native interfacial oxide layer can also be epitaxially regrown under ion irradiation. A critical fluence is needed before the interfacial oxide breaks down and broadens, allowing the epitaxial crystallization to take place. This process is characterized by an activation energy of 0.44 eV. The complex phenomenon of ion-beam-induced crystallization involves a dynamical interaction between production and annealing of point defects. The presence of electrically active dopants probably influences the lifetime of point defects. Impurities which prevent thermal regrowth are instead dissolved by ballistic effects and/or radiation-enhanced mixing.

  12. Electrospray ion beam deposition and mass spectrometry of nonvolatile molecules and nanomaterials

    OpenAIRE

    Rauschenbach, Stephan; Kern, Klaus

    2008-01-01

    The vacuum deposition of complex functional molecules and nanoparticles by thermal sublimation is often hindered due to their extremely low vapor pressure. This especially impedes the application of ultrahigh vacuum (UHV) based analytical and surface modification techniques for the investigation of these extremely interesting systems. On the other hand, specimen prepared under ambient conditions or in solution are typically not sufficiently well-defined and clean to allow a thorough and preci...

  13. Influence of deposition rate on the properties of ZrO2 thin films prepared in electron beam evaporation method

    Institute of Scientific and Technical Information of China (English)

    Dongping Zhang(张东平); Meiqiong Zhan(占美琼); Ming Fang(方明); Hongbo He(贺洪波); Jianda Shao(邵建达); Zhengxiu Fan(范正修)

    2004-01-01

    ZrO2 thin films were prepared in electron beam thermal evaporation method. And the deposition rate changed from 1.3 to 6.3 nm/s in our study. X-ray diffractometer and spectrophotometer were employed to characterize the films. X-ray diffraction (XRD) spectra pattern shows that films structure changed from amorphous to polycrystalline with deposition rate increasing. The results indicate that internal stresses of the films are compressive in most case. Thin films deposited in our study are inhomogeneous, and the inhomogeneity is enhanced with the deposition rate increasing.

  14. X-Ray Studies of GaN Film Grown on Si Using Electrochemical Deposition Techniques

    International Nuclear Information System (INIS)

    This paper reports on the X-ray studies of GaN thin films deposited on Si (111) substrate at different current density using electrochemical deposition technique. The structural properties of GaN films were studied by X-ray diffraction (XRD). XRD analysis showed that hexagonal wurtzite and cubic zinc blende GaN phases were both deposited on Si (111). The lattice constants, the average size of h-GaN crystals and the in-plane (along a-axis) and out of plane (along c-axis) strains were calculated from XRD analysis.

  15. High deposition rate hydrogenated polymorphous silicon characterized by different capacitance techniques

    International Nuclear Information System (INIS)

    High deposition rate hydrogenated polymorphous silicon thin films were analyzed using different capacitance techniques. The distribution of localized states and some electrical properties were studied by the temperature, frequency and bias dependence of the Schottky barrier capacitance and deep level transient spectroscopy. Our different samples present different groups of gap states depending on the preparation conditions. A comparison with standard amorphous silicon films reveals a reduced density of states in the gap for high deposition rate samples. Our results show that the samples, which represent only one group of gap states and lower density of states in the gap, were the samples grown at deposition rate of 8 Α/s. (author)

  16. Electro-optic techniques in electron beam diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    van Tilborg, Jeroen; Toth, Csaba; Matlis, Nicholas; Plateau, Guillaume; Leemans, Wim

    2011-06-17

    Electron accelerators such as laser wakefield accelerators, linear accelerators driving free electron lasers, or femto-sliced synchrotrons, are capable of producing femtosecond-long electron bunches. Single-shot characterization of the temporal charge profile is crucial for operation, optimization, and application of such accelerators. A variety of electro-optic sampling (EOS) techniques exists for the temporal analysis. In EOS, the field profile from the electron bunch (or the field profile from its coherent radiation) will be transferred onto a laser pulse co-propagating through an electro-optic crystal. This paper will address the most common EOS schemes and will list their advantages and limitations. Strong points that all techniques share are the ultra-short time resolution (tens of femtoseconds) and the single-shot capabilities. Besides introducing the theory behind EOS, data from various research groups is presented for each technique.

  17. Electro-optic techniques in electron beam diagnostics

    International Nuclear Information System (INIS)

    Electron accelerators such as laser wakefield accelerators, linear accelerators driving free electron lasers, or femto-sliced synchrotrons, are capable of producing femtosecond-long electron bunches. Single-shot characterization of the temporal charge profile is crucial for operation, optimization, and application of such accelerators. A variety of electro-optic sampling (EOS) techniques exists for the temporal analysis. In EOS, the field profile from the electron bunch (or the field profile from its coherent radiation) will be transferred onto a laser pulse co-propagating through an electro-optic crystal. This paper will address the most common EOS schemes and will list their advantages and limitations. Strong points that all techniques share are the ultra-short time resolution (tens of femtoseconds) and the single-shot capabilities. Besides introducing the theory behind EOS, data from various research groups is presented for each technique.

  18. Evaluation of crystal implantation technique for the measurement of neutral beam composition and energy spectra

    International Nuclear Information System (INIS)

    A promising method of measuring a neutral beam's energy spectrum and impurity content is to implant beam high purity silicon crystals. The depth distribution of the beam particles into the crystal surface is then measured by SIMS (secondary ion mass spectroscopy); the penetration distance is a function of the incident particle energy. The inferred beam energy spectrum can be used to determine the percentages of atomic and molecular ions that comprise the source plasma. Moreover, other elements are analyzed by mass and compared with the total amount of implanted hydrogen in order to obtain a beam impurity content. Previous analysis of a 40 keV ORNL hydrogen beam gave a source species composition that agreed with that obtained by magnetic momentum analysis of the residual ion beam to within the accuracy of the momentum analysis. Crystals have already been irradiated by a 78 keV hydrogen beam from the LBL 30-sec ion source at their Neutral Beam Engineering Test Facility (NBETF); similar exposures are made with the ORNL 30 sec source at the same test stand. Use of the NBETF allows direct comparison with the spectra obtained from the LBL Doppler-shift spectrometer. Although increasing particle energy allows greater peak resolution and increased accuracy, the increasing power density makes proper exposure more difficult. An exposure technique used at ORNL to measure a 70 keV beam is also discussed

  19. Radiation therapy for retinoblastoma: comparison of results with lens-sparing versus lateral beam techniques

    International Nuclear Information System (INIS)

    From 1979 through 1986, 170 children were seen at our institution diagnosed with retinoblastoma. Sixty-six of the children with involvement of 121 eyes, were referred for definitive external beam radiation to one or both eyes. During the study period, two distinct radiation techniques were used. From 1980 through mid-1984, a lens-sparing technique included an anterior electron beam with a contact lens mounted lead shield, combined with a lateral field, was used. Since mid-1984, a modified lateral beam technique has been used, mixing lateral electrons and superior and inferior lateral oblique split beam wedged photons. Doses prescribed were similar for both techniques, ranging from 3,850 to 5,000 cGy in 4 to 5 weeks. The lens-sparing and the modified lateral techniques are compared for local control. For eyes with Group I through III disease, the lens-sparing technique resulted in local control in 33% of the eyes treated, where the modified lateral technique controlled 83% of the eyes treated (p = .006). Mean time to relapse was identical in both groups, that is 24 and 26 months respectively. Most relapses were successfully treated with further local therapy, including laser or cryosurgery, or 60Co plaques. Five eyes required enucleation following initial treatment with the lens-sparing technique, but none thus far with the lateral beam technique. For eyes with Group IV and V disease, no significant differences were found between the two techniques in terms of local control or eventual need for enucleation. With a mean follow-up time of 33 months for the entire group, the 4-year survival is 93%. Two of the 4 deaths are due to second primary tumor, and all 4 have occurred in the lens-sparing group. Because follow-up time is more limited in the lateral beam group, this is not statistically significant and direct survival comparisons are premature

  20. Energy deposition measurements of a large-diameter, intense relativistic electron beam for high-power gas laser excitation

    International Nuclear Information System (INIS)

    Measurements of electron-beam (e-beam) energy deposition in gaseous medium by a segmented totally stopping calorimeter and a pressure jump method are described, both of which gave the same values. Typical e-beam parameters are 2 MV, 80 kA, and 65 ns (FWHM). The e-beam cross-sectional area is 10 cm in diameter. First, the radial distribution of the e-beam current generated from the field-emission diode as a function of the axial magnetic field was measured. Next, for applications to longitudinal excitation of the high-power gas lasers, the e-beam energy deposition characteristics are measured in N2 for the propagation distance up to 2.3 m in terms of the axial magnetic field, the N2 gas pressure, and the radial e-beam distribution. As a result, the axial field equivalent to the self-magnetic field of the electron beam can acceptably control the e-beam generation and propagation uniformities

  1. Structural transitions in electron beam deposited Co–carbonyl suspended nanowires at high electrical current densities

    Directory of Open Access Journals (Sweden)

    Gian Carlo Gazzadi

    2015-06-01

    Full Text Available Suspended nanowires (SNWs have been deposited from Co–carbonyl precursor (Co2(CO8 by focused electron beam induced deposition (FEBID. The SNWs dimensions are about 30–50 nm in diameter and 600–850 nm in length. The as-deposited material has a nanogranular structure of mixed face-centered cubic (FCC and hexagonal close-packed (HCP Co phases, and a composition of 80 atom % Co, 15 atom % O and 5 atom % C, as revealed by transmission electron microscopy (TEM analysis and by energy-dispersive X-ray (EDX spectroscopy, respectively. Current (I–voltage (V measurements with current densities up to 107 A/cm2 determine different structural transitions in the SNWs, depending on the I–V history. A single measurement with a sudden current burst leads to a polycrystalline FCC Co structure extended over the whole wire. Repeated measurements at increasing currents produce wires with a split structure: one half is polycrystalline FCC Co and the other half is graphitized C. The breakdown current density is found at 2.1 × 107 A/cm2. The role played by resistive heating and electromigration in these transitions is discussed.

  2. Structural transitions in electron beam deposited Co-carbonyl suspended nanowires at high electrical current densities.

    Science.gov (United States)

    Gazzadi, Gian Carlo; Frabboni, Stefano

    2015-01-01

    Suspended nanowires (SNWs) have been deposited from Co-carbonyl precursor (Co2(CO)8) by focused electron beam induced deposition (FEBID). The SNWs dimensions are about 30-50 nm in diameter and 600-850 nm in length. The as-deposited material has a nanogranular structure of mixed face-centered cubic (FCC) and hexagonal close-packed (HCP) Co phases, and a composition of 80 atom % Co, 15 atom % O and 5 atom % C, as revealed by transmission electron microscopy (TEM) analysis and by energy-dispersive X-ray (EDX) spectroscopy, respectively. Current (I)-voltage (V) measurements with current densities up to 10(7) A/cm(2) determine different structural transitions in the SNWs, depending on the I-V history. A single measurement with a sudden current burst leads to a polycrystalline FCC Co structure extended over the whole wire. Repeated measurements at increasing currents produce wires with a split structure: one half is polycrystalline FCC Co and the other half is graphitized C. The breakdown current density is found at 2.1 × 10(7) A/cm(2). The role played by resistive heating and electromigration in these transitions is discussed. PMID:26199833

  3. Stability of a current carrying single nanowire of tungsten (W) deposited by focused ion beam

    Science.gov (United States)

    Mandal, Pabitra; Das, Bipul; Raychaudhuri, A. K.

    2016-02-01

    We report an investigation on the stability of single W nanowire (NW) under direct current stressing. The NW of width ≈ 80 nm and thickness ≈ 100 nm was deposited on a SiO2/Si substrate by Focused Ion Beam (FIB) of Ga ions using W(CO)6 as a precursor. Such nanowires, used as interconnects in nanoelectronics, contain C and Ga in addition to W. The stability studies, done for the first time in such FIB deposited NWs, show that under current stressing these NWs behave very differently from that observed in conventional metal NWs or interconnects. The failure of such FIB deposited NW occurs at a relatively low current density (˜1011 A/m2) which is an order or more less than that seen in conventional metal NWs. The failure accompanies with formation of voids and hillocks, suggesting ionic migration as the cause of failure. However, the polarities of void and hillock formations are opposite to those observed in conventional metal interconnects. This observation along with preferential agglomeration of Ga ions in hillocks suggests that the ionic migration in such NWs is dominated by direct force as opposed to the migration driven by electron wind force in conventional metal interconnects.

  4. Deposition of TiN Films by Novel Filter Cathodic Arc Technique

    Institute of Scientific and Technical Information of China (English)

    NIU Er-Wu; FAN Song-Hua; LI Li; L(U) Guo-Hua; FENG Wen-Ran; ZHANG Gu-Ling; YANG Si-Ze

    2006-01-01

    A straight magnetic filtering arc source is used to deposit thin films of titanium nitride.The properties of thefilms depend strongly on the deposition process.TiN films can be deposited directly onto heated substrates in anitrogen atmosphere or onto unbiased substrates by condensing the Ti+ ion beam in about 300 eV N2+ nitrogen ionbombardment.In the latter case.the film stoichiometry is varied from an N:Ti ratio of 0.6-1.1 by controlling thearrival rates of Ti and nitrogen ions.Meanwhile,simple models are used to describe the evolution of compressivestress as function of the arrival ratio and the composition of the ion-assisted TiN films.

  5. Ion beams application to modification of surface layer of solids with particular regard to IBAD method - ion beam assisted deposition realized in the INP; Zastosowanie wiazek jonowych do modyfikowania warstwy wierzchniej cial stalych, ze szczegolnym uwzglednieniem metody IBAD - Ion Beam Assisted Deposition, realizowanej w IFJ

    Energy Technology Data Exchange (ETDEWEB)

    Drwiega, M.; Lipinska, E.

    1992-12-31

    The different trends in ion engineering such as: dynamic ion mixing, ionized cluster beam deposition and ion beam assisted deposition are described. Some examples of properties of surface coatings are given and their applications are presented. The future of ion engineering is described. 48 refs, 12 figs, 4 tabs.

  6. Progress on channel spark development and application of pulsed electron beam deposition (PED) in the field of medical coating work

    International Nuclear Information System (INIS)

    A promising source for Pulsed Electron Beam Deposition (PED) is the channel spark. Recent improvements helped to reduce beam instabilities which up to now have limited the life time of the system. The beam power could be increased and because of better beam quality the transport length of the beam is increased from 1 to several centimeters (up to 10 cm). Together with other improvements on the triggering system and beam transport in dielectric tubes, the channel spark approaches industrial standards. An overview of actual applications in research and industry will be presented. An attractive feature of the pulsed electron beam thin film deposition is the conservation of stoichiometry even during deposition of multi-component earth-alkali and alkali glasses. Specially developed glasses like BIOGLAS registered have the ability to anchor soft living tissue at the surface. In form of a bulk material bio active glasses are brittle limiting its applications. Contrary to brittle bulk material a thin layers on medical implants exhibits reliable bio-functionality. Coating of implants with this category of materials is subject of the European INCOMED project (Innovative Coating of Medical Implants with Soft Tissue Anchoring Ability) which just has started

  7. Ion beam induced defects in solids studied by optical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Comins, J.D. [Materials Physics Research Institute, School of Physics, University of the Witwatersrand, Johannesburg (South Africa); Raman and Luminescence Laboratory, University of the Witwatersrand, Johannesburg (South Africa); DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Johannesburg (South Africa)], E-mail: darrell.comins@wits.ac.za; Amolo, G.O. [Materials Physics Research Institute, School of Physics, University of the Witwatersrand, Johannesburg (South Africa); Derry, T.E.; Connell, S.H. [DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Johannesburg (South Africa); Erasmus, R.M. [Raman and Luminescence Laboratory, University of the Witwatersrand, Johannesburg (South Africa); DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Johannesburg (South Africa); Witcomb, M.J. [DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Johannesburg (South Africa); Electron Microscope Unit, University of the Witwatersrand, Johannesburg (South Africa)

    2009-08-15

    Optical methods can provide important insights into the mechanisms and consequences of ion beam interactions with solids. This is illustrated by four distinctly different systems. X- and Y-cut LiNbO{sub 3} crystals implanted with 8 MeV Au{sup 3+} ions with a fluence of 1 x 10{sup 17} ions/cm{sup 2} result in gold nanoparticle formation during high temperature annealing. Optical extinction curves simulated by the Mie theory provide the average nanoparticle sizes. TEM studies are in reasonable agreement and confirm a near-spherical nanoparticle shape but with surface facets. Large temperature differences in the nanoparticle creation in the X- and Y-cut crystals are explained by recrystallisation of the initially amorphised regions so as to recreate the prior crystal structure and to result in anisotropic diffusion of the implanted gold. Defect formation in alkali halides using ion beam irradiation has provided new information. Radiation-hard CsI crystals bombarded with 1 MeV protons at 300 K successfully produce F-type centres and V-centres having the I{sub 3}{sup -} structure as identified by optical absorption and Raman studies. The results are discussed in relation to the formation of interstitial iodine aggregates of various types in alkali iodides. Depth profiling of I{sub 3}{sup -} and I{sub 5}{sup -} aggregates created in RbI bombarded with 13.6 MeV/A argon ions at 300 K is discussed. The recrystallisation of an amorphous silicon layer created in crystalline silicon bombarded with 100 keV carbon ions with a fluence of 5 x 10{sup 17} ions/cm{sup 2} during subsequent high temperature annealing is studied by Raman and Brillouin light scattering. Irradiation of tin-doped indium oxide (ITO) films with 1 MeV protons with fluences from 1 x 10{sup 15} to 250 x 10{sup 15} ions/cm{sup -2} induces visible darkening over a broad spectral region that shows three stages of development. This is attributed to the formation of defect clusters by a model of defect growth and

  8. Electropolymerization of pyrrole on oxidizable metal under high frequency ultrasound irradiation. Application of focused beam to a selective masking technique

    Energy Technology Data Exchange (ETDEWEB)

    Et Taouil, A. [Institut UTINAM, UMR 6213 CNRS, Universite de Franche-Comte, 30 Avenue de l' observatoire, 25009 Besancon Cedex (France); Lallemand, F., E-mail: fabrice.lallemand@univ-fcomte.f [Institut UTINAM, UMR 6213 CNRS, Universite de Franche-Comte, 30 Avenue de l' observatoire, 25009 Besancon Cedex (France); Hallez, L.; Hihn, J-Y. [Institut UTINAM, UMR 6213 CNRS, Universite de Franche-Comte, 30 Avenue de l' observatoire, 25009 Besancon Cedex (France)

    2010-12-01

    A novel masking technique against polymer deposition based on High Intensity Focused Ultrasound (HIFU) irradiation was developed for the first time. With this in mind, a variety of background salts were tested. Sodium salicylate was found to be the most effective electrolytic medium for pyrrole sonoelectropolymerization on copper as it leads to a very efficient passivating oxide layer preventing copper dissolution while enabling polymer formation independently from sonication. In such a medium, high frequency ultrasound greatly refines surface structure, and a slight increase in doping level is observed. Finally, it was proved that focused ultrasound increases copper dissolution in sodium oxalate electrolyte while preventing polypyrrole deposition. A selected zone on the copper substrate was thus irradiated by the focused ultrasound beam to protect it from polymerization. In a second stage, a self-assembled monolayer was deposited on this polymer-free area to create a surface biphased substrate. This type of masking technique can be proposed as an interesting alternative to lithography as it is easier to carry out and allows chemical waste reduction.

  9. Precision atomic physics techniques for nuclear physics with radioactive beams

    OpenAIRE

    Blaum, Klaus; Dilling, Jens; Nörtershäuser, Wilfried

    2013-01-01

    Atomic physics techniques for the determination of ground-state properties of radioactive isotopes are very sensitive and provide accurate masses, binding energies, Q-values, charge radii, spins, and electromagnetic moments. Many fields in nuclear physics benefit from these highly accurate numbers. They give insight into details of the nuclear structure for a better understanding of the underlying effective interactions, provide important input for studies of fundamental symmetries in physics...

  10. Characterization of a radioactive {sup 11}C beam by means of the associated particle technique

    Energy Technology Data Exchange (ETDEWEB)

    Varela, A.; Policroniades, R.; Murillo, G.; Moreno, E. [ININ, Laboratorio del Acelerador Tandem, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Huerta, A.; Chavez, E.; Ortiz, M. E.; Barron, L.; Curiel, Q. [UNAM, Instituto de Fisica, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Aguilar, C.; Coello, E. A.; Juarez, M. A.; Martinez, J. N. [UNAM, Facultad de Ciencias, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2010-02-15

    This paper describes the results obtained for the production and characterization of a radioactive {sup 11}C beam, by means of the in flight technique and the tandem laboratory of the National Institute of Nuclear Research, Mexico. The {sup 11}C production technique described here, uses the well known associated particle technique with the reaction {sup 2}H({sup 10}B, {sup 11}C)n, in order to obtain a bi univocal correspondence between the radioactive {sup 11}C particles and the associated neutrons. A discussion concerning the possible use of this {sup 11}C beam in the study of the elastic scattering of protons is introduced. (Author)

  11. Non-linear current-voltage characteristics of NS-tunnel junctions prepared by focused ion beam induced deposition

    International Nuclear Information System (INIS)

    We used a focused Ga-ion beam and the precursor W(CO)6 -injected into a vacuum chamber nearby the focal area of the beam- to create tungsten containing superconducting deposits with a critical temperature of about 5.2 K. The deposits were fabricated onto oxidized aluminum contacts pre-patterned by UV-photolithography. I-V- and V-dI/dV- measurements have been performed between 0.3 K and 6 K using a He3-cryostat. For selected beam energies used during deposition the samples show Josephson-junction like behaviour or tunneling of quasiparticles for temperatures below the superconducting transition of aluminum at about 2 K. In the temperature range between the superconducting transitions of the two electrodes Andreev-reflection was observed.

  12. Dosimetric evaluations and comparisons between different techniques (Fan beam, Cone beam, OPT) in the dental industry and not

    International Nuclear Information System (INIS)

    In recent years there has been an impressive evolution and spread of cone beam tomographic equipment, in particular in the dental and maxillofacial surgery. These devices exhibit unique characteristics both from the point of view of the geometric parameters of exposure than the quality of the beams radiating employed. In parallel to this technological development it was dealt with the quantification of the dose to the patient, with a discussion between experts to define what are the variables most appropriate to use and the appropriate ways of measuring. And it is of interest also the discussion on the comparison of the risks associated with the use of this method as an alternative to traditional techniques or other tomographic techniques, both on the criteria of optimization in the realization of the tests.

  13. Verification and application of beam steering Phased Array UT technique for complex structures

    International Nuclear Information System (INIS)

    Phased Array Ultrasonic Testing (PAUT) techniques for complex geometries are greatly progressing. We developed an immersion PAUT which is suitable for complex surface profiles such as nozzles and deformed welded areas. Furthermore, we have developed a shape adaptive beam steering technique for 3D complex surface structures with conventional array probe and flexible coupling gel which makes the immersion beam forming technique usable under dry conditions. This system consists of 3 steps. Step1 is surface profile measurement which based on 3D Synthesis Aperture Focusing Technique (SAFT), Step2 is delay law calculation which could take into account the measured 3D surface profiles and steer a shape adjusted ultrasonic beam, Step3 is shape adjusted B-scope construction. In this paper, verification results of property of this PAUT system using R60 curved specimen and nozzle shaped specimen which simulated actual BWR structure. (author)

  14. High aspect ratio AFM Probe processing by helium-ion-beam induced deposition.

    Science.gov (United States)

    Onishi, Keiko; Guo, Hongxuan; Nagano, Syoko; Fujita, Daisuke

    2014-11-01

    A Scanning Helium Ion Microscope (SHIM) is a high resolution surface observation instrument similar to a Scanning Electron Microscope (SEM) since both instruments employ finely focused particle beams of ions or electrons [1]. The apparent difference is that SHIMs can be used not only for a sub-nanometer scale resolution microscopic research, but also for the applications of very fine fabrication and direct lithography of surfaces at the nanoscale dimensions. On the other hand, atomic force microscope (AFM) is another type of high resolution microscopy which can measure a three-dimensional surface morphology by tracing a fine probe with a sharp tip apex on a specimen's surface.In order to measure highly uneven and concavo-convex surfaces by AFM, the probe of a high aspect ratio with a sharp tip is much more necessary than the probe of a general quadrangular pyramid shape. In this paper we report the manufacture of the probe tip of the high aspect ratio by ion-beam induced gas deposition using a nanoscale helium ion beam of SHIM.Gas of platinum organic compound was injected into the sample surface neighborhood in the vacuum chamber of SHIM. The decomposition of the gas and the precipitation of the involved metal brought up a platinum nano-object in a pillar shape on the normal commercial AFM probe tip. A SHIM system (Carl Zeiss, Orion Plus) equipped with the gas injection system (OmniProbe, OmniGIS) was used for the research. While the vacuum being kept to work, we injected platinum organic compound ((CH3)3(CH3C5H4)Pt) into the sample neighborhood and irradiated the helium ion beam with the shape of a point on the apex of the AFM probe tip. It is found that we can control the length of the Pt nano-pillar by irradiation time of the helium ion beam. The AFM probe which brought up a Pt nano-pillar is shown in Figure 1. It is revealed that a high-aspect-ratio Pt nano-pillar of ∼40nm diameter and up to ∼2000 nm length can be grown. In addition, for possible heating

  15. Liquid phase deposition of polymers on arbitrary shaped surfaces and their suitability for e-beam patterning

    Energy Technology Data Exchange (ETDEWEB)

    Paeivaenranta, B; Leinonen, K; Kuittinen, M [University of Joensuu, Department of Physics and Mathematics, PO Box 111, FL-80101 Joensuu (Finland); Pudas, M; Pitkaenen, O [University of Oulu Microelectronics and Material Physics Laboratories and Empart Research Group of Infotech Oulu, Linnanmaa, PO Box 4500, FL-90014 Oulu (Finland); Baroni, P-Y; Scharf, T; Herzig, H-P [University of Neuchatel, Institute of MicroTechnology, A.-L. Breguet 2, 2000 Neuchatel (Switzerland)], E-mail: birgit.paivanranta@joensuu.fi

    2009-06-03

    We present a straightforward low cost liquid phase deposition method to coat arbitrary-shaped dielectric substrates with uniform electron beam sensitive polymer films. Furthermore, we investigate the use of electron beam lithography to pattern the coated pre-form substrates. The polymers studied are poly-methyl-methacrylate with different molecular weights, poly(methyl methacrylate-co-ethyl acrylate) and methyl methacrylate. The polymer coverage over the whole surface area is shown to be uniform and the thickness of the film dependent on the concentration of the polymer liquid used. As the uniform polymer layer is deposited on non-flat surfaces, we show that with an electron beam various surfaces, e.g. microlens arrays, can be re-patterned accurately with nanoscale features. Furthermore, we show the required dose for electron beam exposure to be dependent on the concentration and on the molecular weight of the polymer used.

  16. Measurement techniques for respiratory tract deposition of airborne nanoparticles: a critical review.

    Science.gov (United States)

    Löndahl, Jakob; Möller, Winfried; Pagels, Joakim H; Kreyling, Wolfgang G; Swietlicki, Erik; Schmid, Otmar

    2014-08-01

    Determination of the respiratory tract deposition of airborne particles is critical for risk assessment of air pollution, inhaled drug delivery, and understanding of respiratory disease. With the advent of nanotechnology, there has been an increasing interest in the measurement of pulmonary deposition of nanoparticles because of their unique properties in inhalation toxicology and medicine. Over the last century, around 50 studies have presented experimental data on lung deposition of nanoparticles (typical diameter≤100 nm, but here≤300 nm). These data show a considerable variability, partly due to differences in the applied methodologies. In this study, we review the experimental techniques for measuring respiratory tract deposition of nano-sized particles, analyze critical experimental design aspects causing measurement uncertainties, and suggest methodologies for future studies. It is shown that, although particle detection techniques have developed with time, the overall methodology in respiratory tract deposition experiments has not seen similar progress. Available experience from previous research has often not been incorporated, and some methodological design aspects that were overlooked in 30-70% of all studies may have biased the experimental data. This has contributed to a significant uncertainty on the absolute value of the lung deposition fraction of nanoparticles. We estimate the impact of the design aspects on obtained data, discuss solutions to minimize errors, and highlight gaps in the available experimental set of data. PMID:24151837

  17. Nanostructured Na-doped vanadium oxide synthesized using an anodic deposition technique for supercapacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Chun-Hung; Lin, Chung-Kwei [Department of Materials Science and Engineering, Feng Chia University, Taiwan (China); Lee, Sheng-Wei; Li, Hui-Ying [Institute of Materials Science and Engineering, National Central University, Taiwan (China); Chang, Jeng-Kuei, E-mail: jkchang@ncu.edu.tw [Institute of Materials Science and Engineering, National Central University, Taiwan (China); Deng, Ming-Jay [National Synchrotron Radiation Research Center, Taiwan (China)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Na-doped vanadium oxide is successfully prepared by an electrodeposition technique. Black-Right-Pointing-Pointer Microstructure and Na content of the oxide are controlled by deposition potential. Black-Right-Pointing-Pointer A lower deposition potential leads to a higher porosity of the prepared oxide. Black-Right-Pointing-Pointer Na doping significantly increases the oxide capacitance. Black-Right-Pointing-Pointer The nanostructured Na-doped oxide shows an ideal supercapacitor performance. - Abstract: Vanadium-based oxides are prepared on graphite substrates by an anodic deposition technique. The plating bath is 0.2 M VOSO{sub 4} solution with NaCH{sub 3}COO addition. A scanning electron microscope and an X-ray diffractometer are used to characterize the deposits; the analyses indicate that the porous Na-doped V{sub 2}O{sub 5} electrodes with a nano-crystalline nature are obtained. Supercapacitor properties of the oxide electrodes are studied using cyclic voltammetry in KCl aqueous electrolyte. The data show that the deposited oxides can exhibit ideal capacitive behavior over a potential range of 1 V; the optimum specific capacitance is {approx}180 F/g. A lower deposition potential leads to a higher porosity of the oxide, resulting in a better high-rate supercapacitor performance of the electrode.

  18. Beaming teaching application: recording techniques for spatial xylophone sound rendering

    DEFF Research Database (Denmark)

    Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup; Hoffmann, Pablo F.; Hammershøi, Dorte

    played at student's location is required at teacher's site. This paper presents a comparison of different recording techniques for a spatial xylophone sound rendering. Directivity pattern of the xylophone was measured and spatial properties of the sound field created by a xylophone as a distributed sound...... source were analyzed. Xylophone recordings were performed using different microphone configurations: one and two-channel recording setups are implemented. Recordings were carried out in standard listening room and in an anechoic chamber. Differences between anechoic and reverberant xylophone sound for...

  19. Influence of solution deposition rate on properties of V2O5 thin films deposited by spray pyrolysis technique

    Science.gov (United States)

    Abd-Alghafour, N. M.; Ahmed, Naser M.; Hassan, Zai; Mohammad, Sabah M.

    2016-07-01

    Vanadium oxide (V2O5) thin films were deposited on glass substrates by using a cost-efficient spray pyrolysis technique. The films were grown at 350° through thermal decomposition of VCl3 in deionized water with different solution spray rates. The high resolution X-ray diffraction results revealed the formation of nanocrystalline films having orthorhombic structures with preferential orientation along (101) direction. The spray rate influenced the surface morphology and crystallite size of the films. The crystallite size was found to increase whereas the micro-strain was decreased by increasing the spray deposition rates. The increase in crystallite size and decrease in the macrostrain resulted in an improvement in the films' crystallinity. The UV-Visible spectroscopy analysis indicated that the average transmittance of all films lies in the range 75-80 %. The band gap of V2O5 film was decreased from 2.65 to 2.46 eV with increase of the spray deposition rate from 5 ml/min to 10 ml/min. first, second, and third level headings (first level heading).

  20. Low-temperature transport in ultra-thin tungsten films grown by focused-ion-beam deposition

    OpenAIRE

    Chiatti, O.; Warburton, P. A.

    2010-01-01

    We have fabricated tungsten-containing films by focused-ion-beam (FIB)-induced chemical vapour deposition. By using ion-beam doses below 50 pC/μm² on a substrate of amorphous silicon, we have grown continuous films with thickness below 20 nm. The low-temperature electron transport properties were investigated by measuring current-voltage characteristics for temperatures down to 400 mK and in magnetic fields up to 8 T. FIB-deposited tungsten films are known to have an enhanced transition tem­p...

  1. Continuous electropolishing of Hastelloy substrates for ion-beam assisted deposition of MgO

    Energy Technology Data Exchange (ETDEWEB)

    Kreiskott, Sascha; Arendt, Paul N; Bronisz, Lawrence E; Foltyn, Steve R; Matias, Vladimir [Superconductivity Technology Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2003-05-01

    We demonstrate the applicability of continuous electropolishing for the preparation of metal tapes for ion-beam assisted deposition of MgO for the fabrication of in-plane textured template layers. These templates are used for the fabrication of second generation high temperature superconducting wires utilizing YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} coatings on metallic substrates. Surface roughness values below 1 nm and local slopes of less than 1 deg. could be achieved with the electropolishing process. Mean surface roughness values are lower with the use of electropolishing and slopes of surface roughness inclines are significantly reduced compared to the best results of mechanical polishing (3.5 nm and 5 deg., respectively). The cost-effective process of electropolishing shows great promise for the fabrication of second generation high temperature superconducting wire.

  2. Continuous electropolishing of Hastelloy substrates for ion-beam assisted deposition of MgO

    International Nuclear Information System (INIS)

    We demonstrate the applicability of continuous electropolishing for the preparation of metal tapes for ion-beam assisted deposition of MgO for the fabrication of in-plane textured template layers. These templates are used for the fabrication of second generation high temperature superconducting wires utilizing YBa2Cu3O7-δ coatings on metallic substrates. Surface roughness values below 1 nm and local slopes of less than 1 deg. could be achieved with the electropolishing process. Mean surface roughness values are lower with the use of electropolishing and slopes of surface roughness inclines are significantly reduced compared to the best results of mechanical polishing (3.5 nm and 5 deg., respectively). The cost-effective process of electropolishing shows great promise for the fabrication of second generation high temperature superconducting wire

  3. Focused-electron-beam-induced-deposited cobalt nanopillars for nanomagnetic logic

    Science.gov (United States)

    Sharma, N.; van Mourik, R. A.; Yin, Y.; Koopmans, B.; Parkin, S. S. P.

    2016-04-01

    Nanomagnetic logic (NML) intends to alleviate problems of continued miniaturization of CMOS-based electronics, such as energy dissipation through heat, through advantages such as low power operation and non-volatile magnetic elements. In line with recent breakthroughs in NML with perpendicularly magnetized elements formed from thin films, we have fabricated NML inverter chains from Co nanopillars by focused electron beam induced deposition (FEBID) that exhibit shape-induced perpendicular magnetization. The flexibility of FEBID allows optimization of NML structures. Simulations reveal that the choice of nanopillar dimensions is critical to obtain the correct antiferromagnetically coupled configuration. Experiments carrying the array through a clocking cycle using the Oersted field from an integrated Cu wire show that the array responds to the clocking cycle.

  4. Focused-electron-beam-induced-deposited cobalt nanopillars for nanomagnetic logic.

    Science.gov (United States)

    Sharma, N; van Mourik, R A; Yin, Y; Koopmans, B; Parkin, S S P

    2016-04-22

    Nanomagnetic logic (NML) intends to alleviate problems of continued miniaturization of CMOS-based electronics, such as energy dissipation through heat, through advantages such as low power operation and non-volatile magnetic elements. In line with recent breakthroughs in NML with perpendicularly magnetized elements formed from thin films, we have fabricated NML inverter chains from Co nanopillars by focused electron beam induced deposition (FEBID) that exhibit shape-induced perpendicular magnetization. The flexibility of FEBID allows optimization of NML structures. Simulations reveal that the choice of nanopillar dimensions is critical to obtain the correct antiferromagnetically coupled configuration. Experiments carrying the array through a clocking cycle using the Oersted field from an integrated Cu wire show that the array responds to the clocking cycle. PMID:26941232

  5. Design and Simulation of Symmetric Nanostructures Using Two-beam Modulated Interference Lithography Technique

    CERN Document Server

    Raj, A Alfred Kiruba; Devaprakasam, D

    2013-01-01

    Interferometry lithography is a maturing technology for patterning sub-micron structures in arrays covering large areas. This paper presents a method for the measurement of nanoscale surface patterns produced by two-beam laser interference lithography (LIL). The objective in this study is to simulate and design periodic and quasi-periodic 1D, 2D and 3D nanostructures using two-beam interference technique. We designed and simulated periodic and quasi-periodic structures by two-beam interference patterning using a MATLAB program by varying angle of incidence, wavelength and geometry. The simulated patterns show that the symmetries of the interference maxima depend mostly on the angles of incidence and perturbations of incidents beams. Using this technique, we can achieve potentially high-volume of uniformity, throughput, process control, and repeatability. By varying different input parameters, we have optimized simulated patterns with controlled periodicity, density and aspect ratio also it can be programmed t...

  6. Experimental demonstration of tomographic slit technique for measurement of arbitrary intensity profiles of light beams

    Science.gov (United States)

    Soto, José; Rendón, Manuel; Martín, Manuel

    1997-10-01

    We demonstrate experimentally an optical imaging method that makes use of a slit to collect tomographic projection data of arbitrarily shaped light beams; a tomographic backprojection algorithm is then used to reconstruct the intensity profiles of these beams. Two different implementations of the method are presented. In one, a single slit is scanned and rotated in front of the laser beam. In the other, the sides of a polygonal slit, which is linearly displaced in a x-y plane perpendicular to the beam, are used to collect the data. This latter version is more suitable than the other for adaptation at micrometer-size scale. A mathematical justification is given here for the superior performance against laser-power fluctuations of the tomographic slit technique compared with the better-known tomographic knife-edge technique.

  7. Application of Real-time Digitization Technique in Beam Measurement for Accelerators

    CERN Document Server

    Zhao, Lei; Gao, Xingshun; Liu, Shubin; An, Qi

    2015-01-01

    Beam measurement is very important for accelerators. With the development of analog-to-digital conversion techniques, digital beam measurement becomes a research hot spot. IQ (In-phase & Quadrature-phase) analysis based method is an important beam measurement approach, the principle of which is presented and discussed in this paper. The State Key Laboratory of Particle Detection and Electronics in University of Science and Technology of China has devoted efforts to the research of digital beam measurement based on high-speed high-resolution analog-to-digital conversion, and a series of beam measurement instruments were designed for China Spallation Neutron Source (CSNS), Shanghai Synchrotron Radiation Facility (SSRF), and Accelerator Driven Sub-critical system (ADS).

  8. Ultrasonic spray coating as deposition technique for the light-emitting layer in polymer LEDs

    OpenAIRE

    GILISSEN, Koen; Stryckers, Jeroen; VERSTAPPEN, Pieter; DRIJKONINGEN, Jeroen; HEINTGES, Gael; Lutsen, Laurence; Manca, Jean; Maes, Wouter; Deferme, Wim

    2015-01-01

    In this work the ultrasonic spray coating technique is introduced as an alternative wet solution process for the deposition of the (Super Yellow) light-emitting layer for polymer light-emitting diodes (PLEDs). An investigation on the use of this coating technique in ambient conditions is performed and a comparison with spin coated PLEDs in inert atmosphere is made. Uniform low roughness thin films with a typical thickness of 80 nm are obtained by varying the polymer–solvent mixture and spray ...

  9. Electrical furnace for producing carbide coatings using the thermoreactive deposition/diffusion technique

    OpenAIRE

    FABIO CASTILLEJO; DIANA MARULANDA; OLIVO RODRIGUEZ; JHON OLAYA

    2011-01-01

    In this work, the design of an electrical furnace for producing transition metal-based hard coatings using the thermo-reactive deposition and diffusion (TRD) technique is described. Performance of the system was tested through production of vanadium carbide (VC) and niobium carbide (NbC) coatings on steel AISI D2. X-ray diffraction (XRD) and optical microscopy techniques were used to study phase formation and microstructure, respectively. Hardness was determined by using Knoop microhardness m...

  10. Modification of properties of TiB2 coatings by ion beam mixing during deposition

    International Nuclear Information System (INIS)

    We have deposited TiB2 ceramic coatings at room temperature using the dynamic ion-mixing (DIM) technique. The influence of a high energy, heavy ion bombardment of the growing film was investigated and the structural characterization performed by means of transmission electron microscopy either on thin films or on cross-sectional preparations. The TiB2 coatings prepared by DIM are crystallized with a hexagonal structure whereas those prepared without ion mixing are principlally amorphous. Scratch adhesion tests indicate that the adhesion can be greatly improved by intermixing of the film and substrate during the earliest stages of the deposition. The relative hardness increase of the coated tool steel substrate was of the order of 15%-22% and the true film hardness was deduced either by calculation from a composite model or by ultralow load indentations. (orig.)

  11. Growth Assisted by Glancing Angle Deposition: A New Technique to Fabricate Highly Porous Anisotropic Thin Films.

    Science.gov (United States)

    Sanchez-Valencia, Juan Ramon; Longtin, Remi; Rossell, Marta D; Gröning, Pierangelo

    2016-04-01

    We report a new methodology based on glancing angle deposition (GLAD) of an organic molecule in combination with perpendicular growth of a second inorganic material. The resulting thin films retain a very well-defined tilted columnar microstructure characteristic of GLAD with the inorganic material embedded inside the columns. We refer to this new methodology as growth assisted by glancing angle deposition or GAGLAD, since the material of interest (here, the inorganic) grows in the form of tilted columns, though it is deposited under a nonglancing configuration. As a "proof of concept", we have used silver and zinc oxide as the perpendicularly deposited material since they usually form ill-defined columnar microstructures at room temperature by GLAD. By means of our GAGLAD methodology, the typical tilted columnar microstructure can be developed for materials that otherwise do not form ordered structures under conventional GLAD. This simple methodology broadens significantly the range of materials where control of the microstructure can be achieved by tuning the geometrical deposition parameters. The two examples presented here, Ag/Alq3 and ZnO/Alq3, have been deposited by physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD), respectively: two different vacuum techniques that illustrate the generality of the proposed technique. The two type of hybrid samples present very interesting properties that demonstrate the potentiality of GAGLAD. On one hand, the Ag/Alq3 samples present highly optical anisotropic properties when they are analyzed with linearly polarized light. To our knowledge, these Ag/Alq3 samples present the highest angular selectivity reported in the visible range. On the other hand, ZnO/Alq3 samples are used to develop highly porous ZnO thin films by using Alq3 as sacrificial material. In this way, antireflective ZnO samples with very low refractive index and extinction coefficient have been obtained. PMID:26954074

  12. Vietnam Project For Production Of Radioactive Beam Based On ISOL Technique With The Dalat Reactor

    International Nuclear Information System (INIS)

    The presence in Vietnam of Dalat nuclear reactor dedicated to fundamental studies is a unique opportunity to produce Radioactive Ion (RI) Beams with the fission of a 235U induced by the thermal neutrons produced by the reactor. We propose to produce RI beams at the Dalat nuclear reactor using ISOL (Isotope Separation On-Line) technique. This project should be a unique opportunity for Vietnamese nuclear physics community to use its own facilities to produce RI beams for studying nuclear physics at an international level. (author)

  13. The study of metal sulphide nanomaterials obtained by chemical bath deposition and hot-injection technique

    Science.gov (United States)

    Maraeva, E. V.; Alexandrova, O. A.; Forostyanaya, N. A.; Levitskiy, V. S.; Mazing, D. S.; Maskaeva, L. N.; Markov, V. Ph; Moshnikov, V. A.; Shupta, A. A.; Spivak, Yu M.; Tulenin, S. S.

    2015-11-01

    In this study lead sulphide - cadmium sulphide based layers were obtained through chemical deposition of water solutions and cadmium sulphide quantum dots were formed through hot-injection technique. The article discusses the results of surface investigations with the use of atomic force microscopy, Raman spectroscopy and photoluminescence measurements.

  14. Influence of deposition temperature on the microstructure and thermoelectric properties of antimonide cobalt thin films prepared by ion beam sputtering deposition

    International Nuclear Information System (INIS)

    Highlights: • Co–Sb films were prepared by ion beam sputtering using fan-shape target. • The carrier concentration is suitable for obtaining high-quality sample. • Co–Sb thin film with mixed CoSb3 and Sb phase has highest power factor. - Abstract: Antimonide cobalt thin films were deposited on BK7 glass substrates at various substrate temperatures by ion beam sputtering deposition with a fan-shape target. The influence of deposition temperature on the microstructure and thermoelectric properties of antimonide cobalt thin films were systematically investigated. It is found that the Seebeck coefficient of the thin film increases at first and then decreases with the increasing deposition temperature. The Seebeck coefficient of the sample deposited at 250 °C has maximum value and increases stably when the measuring temperature increased from room-temperature to 600 K. The electrical conductivity of the thin film increases significantly to 5.6 × 104 S cm−1 when the deposition temperature was 450 °C and then decreases greatly when the temperature increased to 500 °C and 550 °C. The behavior of electrical conductivity of the sample deposited at 250 °C changes from metallic to semiconducting after the measuring temperature exceeded 540 K. The power factor of antimonide cobalt thin film deposited at 250 °C has a maximum value of 0.93 × 10−4 W m−1 K−2 at room-temperature and then increases to 3.5 × 10−4 W m−1 K−2 when the measuring temperature was 540 K

  15. Closed-Loop Process Control for Electron Beam Freeform Fabrication and Deposition Processes

    Science.gov (United States)

    Taminger, Karen M. (Inventor); Hafley, Robert A. (Inventor); Martin, Richard E. (Inventor); Hofmeister, William H. (Inventor)

    2013-01-01

    A closed-loop control method for an electron beam freeform fabrication (EBF(sup 3)) process includes detecting a feature of interest during the process using a sensor(s), continuously evaluating the feature of interest to determine, in real time, a change occurring therein, and automatically modifying control parameters to control the EBF(sup 3) process. An apparatus provides closed-loop control method of the process, and includes an electron gun for generating an electron beam, a wire feeder for feeding a wire toward a substrate, wherein the wire is melted and progressively deposited in layers onto the substrate, a sensor(s), and a host machine. The sensor(s) measure the feature of interest during the process, and the host machine continuously evaluates the feature of interest to determine, in real time, a change occurring therein. The host machine automatically modifies control parameters to the EBF(sup 3) apparatus to control the EBF(sup 3) process in a closed-loop manner.

  16. Dual-ion-beam deposition of carbon films with diamond-like properties

    Science.gov (United States)

    Mirtich, M. J.; Swec, D. M.; Angus, J. C.

    1985-01-01

    A single and dual ion beam system was used to generate amorphous carbon films with diamond like properties. A methane/argon mixture at a molar ratio of 0.28 was ionized in the low pressure discharge chamber of a 30-cm-diameter ion source. A second ion source, 8 cm in diameter was used to direct a beam of 600 eV Argon ions on the substrates (fused silica or silicon) while the deposition from the 30-cm ion source was taking place. Nuclear reaction and combustion analysis indicate H/C ratios for the films to be 1.00. This high value of H/C, it is felt, allowed the films to have good transmittance. The films were impervious to reagents which dissolve graphitic and polymeric carbon structures. Although the measured density of the films was approximately 1.8 gm/cu cm, a value lower than diamond, the films exhibited other properties that were relatively close to diamond. These films were compared with diamond like films generated by sputtering a graphite target.

  17. Mechanical properties of silicon oxynitride thin films prepared by low energy ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Shima, Yukari; Hasuyama, Hiroki E-mail: hasuyama@cc.kurume-it.ac.jp; Kondoh, Toshiharu; Imaoka, Yasuo; Watari, Takanori; Baba, Koumei; Hatada, Ruriko

    1999-01-02

    Silicon oxynitride (SiO{sub x}N{sub y}) films (0.1-0.7 {mu}m) were produced on Si (1 0 0), glass and 316L stainless steel substrates by ion beam assisted deposition (IBAD) using Si evaporation and the concurrent bombardment with a mixture of 200 eV N{sub 2} and Ar, or O{sub 2} and Ar ions. Adhesion was evaluated by pull-off tests. Film hardness was measured by a nanoindentation system with AFM. The measurement of internal stress in the films was carried out by the Stoney method. The film structure was examined by GXRD. XPS was employed to measure the composition of films and to analyze the chemical bonds. The dependence of mechanical properties on the film thickness and the processing temperature during deposition was studied. Finally, the relations between the mechanical properties of the films and the correlation with corrosion-protection ability of films are discussed and summarized.

  18. Structural and electrical properties of ion beam sputter deposited tantalum films

    Energy Technology Data Exchange (ETDEWEB)

    Sajovec, F.; Meuffels, P.M.; Schober, T. (Forschungszentrum Juelich G.m.b.H., Inst. fuer Festkoerperforschung, Juelich (Germany))

    1992-10-30

    In situ resistance measurements during the growth of ion beam sputter deposited tantalum films have been employed to elucidate the conditions necessary for the formation of either the b.c.c. ([alpha]-Ta) or the tetragonal ([beta]-Ta) structure. Tantalum films condense at room temperature onto sputter-cleaned fused silica substrates as the [beta] phase with resistivities [rho] in the range 200-220 [mu][Omega] cm. [alpha]-Ta films with [rho] between 40 and 55 [mu][Omega] cm can be prepared if the films are deposited on top of thin (more than 3 nm) niobium underlayers. The niobium underlayer thickness is very critical with respect to the nucleation process of tantalum. When it is less than 3 nm, tantalum films consisting of mixtures of [alpha]-Ta and [beta]-Ta result. This is because niobium on fused silica nucleates first in a structure differing from the common b.c.c. structure. This phase cannot promote the nucleation of pure [alpha]-Ta. It converts to b.c.c.-Nb if the layer thickness exceeds 3 nm.

  19. Post-growth purification of Co nanostructures prepared by focused electron beam induced deposition

    Science.gov (United States)

    Begun, E.; Dobrovolskiy, O. V.; Kompaniiets, M.; Sachser, R.; Gspan, Ch; Plank, H.; Huth, M.

    2015-02-01

    In the majority of cases nanostructures prepared by focused electron beam induced deposition (FEBID) employing an organometallic precursor contain predominantly carbon-based ligand dissociation products. This is unfortunate with regard to using this high-resolution direct-write approach for the preparation of nanostructures for various fields, such as mesoscopic physics, micromagnetism, electronic correlations, spin-dependent transport and numerous applications. Here we present an in situ cleaning approach to obtain pure Co-FEBID nanostructures. The purification procedure lies in the exposure of heated samples to a H2 atmosphere in conjunction with the irradiation by low-energy electrons. The key finding is that the combination of annealing at 300 °C, H2 exposure and electron irradiation leads to compact, carbon- and oxygen free Co layers down to a thickness of about 20 nm starting from as-deposited Co-FEBID structures. In addition to this, in temperature-dependent electrical resistance measurements on post-processed samples we find a typical metallic behavior. In low-temperature magnetoresistance and Hall effect measurements we observe ferromagnetic behavior.

  20. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    OpenAIRE

    Abat, E.; Abdallah, J. M.; Addy, T. N.; Adragna, P.; Aharrouche, M.; Ahmad, A; Akesson, T. P. A.; Aleksa, M.; Alexa, C; Anderson, K.; Andreazza, A.; Anghinolfi, F.; Antonaki, A.; Arabidze, G.; Arik, E.

    2016-01-01

    A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Gea...

  1. Ultraviolet optical and microstructural properties of MgF2 and LaF3 coatings deposited by ion-beam sputtering and boat and electron-beam evaporation

    International Nuclear Information System (INIS)

    Single layers of MgF2 and LaF3 were deposited upon superpolished fused-silica and CaF2 substrates by ion-beam sputtering (IBS) as well as by boat and electron beam (e-beam) evaporation and were characterized by a variety of complementary analytical techniques. Besides undergoing photometric and ellipsometric inspection, the samples were investigated at 193 and 633 nm by an optical scatter measurement facility. The structural properties were assessed with atomic-force microscopy, x-ray diffraction, TEM techniques that involved conventional thinning methods for the layers. For measurement of mechanical stress in the coatings, special silicon substrates were coated and analyzed. The dispersion behavior of both deposition materials, which was determined on the basis of various independent photometric measurements and data reduction techniques, is in good agreement with that published in the literature and with the bulk properties of the materials. The refractive indices of the MgF2 coatings ranged from 1.415 to 1.440 for the wavelength of the ArF excimer laser (193 nm) and from 1.435 to 1.465 for the wavelength of the F2 excimer laser (157 nm). For single layers of LaF3 the refractive indices extended from 1.67 to 1.70 at 193 nm to ∼1.80 at 157 nm. The IBS process achieves the best homogeneity and the lowest surface roughness values (close to 1 nmrms) of the processes compared in the joint experiment. In contrast to MgF2 boat and e-beam evaporated coatings, which exhibit tensile mechanical stress ranging from 300 to 400 MPa, IBS coatings exhibit high compressive stress of as much as 910 MPa. A similar tendency was found for coating stress in LaF3 single layers. Experimental results are discussed with respect to the microstructural and compositional properties as well as to the surface topography of the coatings

  2. Efficient focusing of 8 keV X-rays with multilayer Fresnel zone plates fabricated by atomic layer deposition and focused ion beam milling

    OpenAIRE

    Mayer, Marcel; Keskinbora, Kahraman; Grévent, Corinne; Szeghalmi, Adriana; Knez, Mato; Weigand, Markus; Snigirev, Anatoly; Snigireva, Irina; Schütz, Gisela

    2013-01-01

    Fresnel zone plates (FZPs) recently showed significant improvement by focusing soft X-rays down to ∼10 nm. In contrast to soft X-rays, generally a very high aspect ratio FZP is needed for efficient focusing of hard X-rays. Therefore, FZPs had limited success in the hard X-ray range owing to difficulties of manufacturing high-aspect-ratio zone plates using conventional techniques. Here, employing a method of fabrication based on atomic layer deposition (ALD) and focused ion beam (FIB) milling,...

  3. Effect of Substrate Temperature on Structural and Optical Properties of Nanocrystalline CdTe Thin Films Deposited by Electron Beam Evaporation

    Directory of Open Access Journals (Sweden)

    M. Rigana Begam

    2013-07-01

    Full Text Available Nanocrystalline Cadmium Telluride (CdTe thin films were deposited onto glass substrates using electron beam evaporation technique. The effect of substrate temperature on the structural, morphological and optical properties of CdTe thin films has been investigated. All the CdTe films exhibited zinc blende structure with (111 preferential orientation. The crystallite size of the films increased from 35 nm to 116 nm with the increase of substrate temperature and the band gap of the films decreased from 2.87 eV to 2.05 eV with the increase of the crystallite size.

  4. Chemical composition, morphology and optical properties of zinc sulfide coatings deposited by low-energy electron beam evaporation

    International Nuclear Information System (INIS)

    The research determines the features of formation, morphology, chemical composition and optical properties of the coatings deposited by the method, proposed for the first time, of the exposure of mechanical mixture of zinc and sulfur powders to low-energy electron beam evaporation. The findings show that the deposited coatings are characterized by high chemical and structural homogeneity in thickness. The study considers the influence of substrate temperature and thickness of the deposited layer on the morphology and the width of the formed ZnS thin layers band gap. Also was shown the possibility to form ZnS coatings with this method using the mixture of zinc and copper sulfide powders.

  5. Chemical composition, morphology and optical properties of zinc sulfide coatings deposited by low-energy electron beam evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Ragachev, A.V. [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Yarmolenko, M.A., E-mail: simmak79@mail.ru [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Rogachev, A.A. [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Gorbachev, D.L. [Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Zhou, Bing [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2014-06-01

    The research determines the features of formation, morphology, chemical composition and optical properties of the coatings deposited by the method, proposed for the first time, of the exposure of mechanical mixture of zinc and sulfur powders to low-energy electron beam evaporation. The findings show that the deposited coatings are characterized by high chemical and structural homogeneity in thickness. The study considers the influence of substrate temperature and thickness of the deposited layer on the morphology and the width of the formed ZnS thin layers band gap. Also was shown the possibility to form ZnS coatings with this method using the mixture of zinc and copper sulfide powders.

  6. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    International Nuclear Information System (INIS)

    A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20GeV and 180GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by between 11% and 25% compared to the resolution at the electromagnetic scale.

  7. A Layer Correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    CERN Document Server

    Abat, E; Addy, T N; Adragna, P; Aharrouche, M; Ahmad, A; Akesson, T P A; Aleksa, M; Alexa, C; Anderson, K; Andreazza, A; Anghinolfi, F; Antonaki, A; Arabidze, G; Arik, E; Atkinson, T; Baines, J; Baker, O K; Banfi, D; Baron, S; Barr, A J; Beccherle, R; Beck, H P; Belhorma, B; Bell, P J; Benchekroun, D; Benjamin, D P; Benslama, K; Bergeaas Kuutmann, E; Bernabeu, J; Bertelsen, H; Binet, S; Biscarat, C; Boldea, V; Bondarenko, V G; Boonekamp, M; Bosman, M; Bourdarios, C; Broklova, Z; Burckhart Chromek, D; Bychkov, V; Callahan, J; Calvet, D; Canneri, M; Capeans Garrido, M; Caprini, M; Cardiel Sas, L; Carli, T; Carminati, L; Carvalho, J; Cascella, M; Castillo, M V; Catinaccio, A; Cauz, D; Cavalli, D; Cavalli Sforza, M; Cavasinni, V; Cetin, S A; Chen, H; Cherkaoui, R; Chevalier, L; Chevallier, F; Chouridou, S; Ciobotaru, M; Citterio, M; Clark, A; Cleland, B; Cobal, M; Cogneras, E; Conde Muino, P; Consonni, M; Constantinescu, S; Cornelissen, T; Correard, S; Corso Radu, A; Costa, G; Costa, M J; Costanzo, D; Cuneo, S; Cwetanski, P; Da Silva, D; Dam, M; Dameri, M; Danielsson, H O; Dannheim, D; Darbo, G; Davidek, T; De, K; Defay, P O; Dekhissi, B; Del Peso, J; Del Prete, T; Delmastro, M; Derue, F; Di Ciaccio, L; Di Girolamo, B; Dita, S; Dittus, F; Djama, F; Djobava, T; Dobos, D; Dobson, M; Dolgoshein, B A; Dotti, A; Drake, G; Drasal, Z; Dressnandt, N; Driouchi, C; Drohan, J; Ebenstein, W L; Eerola, P; Efthymiopoulos, I; Egorov, K; Eifert, T F; Einsweiler, K; El Kacimi, M; Elsing, M; Emelyanov, D; Escobar, C; Etienvre, A I; Fabich, A; Facius, K; Fakhr-Edine, A I; Fanti, M; Farbin, A; Farthouat, P; Fassouliotis, D; Fayard, L; Febbraro, R; Fedin, O L; Fenyuk, A; Fergusson, D; Ferrari, P; Ferrari, R; Ferreira, B C; Ferrer, A; Ferrere, D; Filippini, G; Flick, T; Fournier, D; Francavilla, P; Francis, D; Froeschl, R; Froidevaux, D; Fullana, E; Gadomski, S; Gagliardi, G; Gagnon, P; Gallas, M; Gallop, B J; Gameiro, S; Gan, K K; Garcia, R; Garcia, C; Gavrilenko, I L; Gemme, C; Gerlach, P; Ghodbane, N; Giakoumopoulou, V; Giangiobbe, V; Giokaris, N; Glonti, G; Göttfert, T.; Golling, T; Gollub, N; Gomes, A; Gomez, M D; Gonzalez-Sevilla, S; Goodrick, M J; Gorfine, G; Gorini, B; Goujdami, D; Grahn, K J; Grenier, P; Grigalashvili, N; Grishkevich, Y; Grosse-Knetter, J; Gruwe, M; Guicheney, C; Gupta, A; Haeberli, C; Härtel, R.; Hajduk, Z; Hakobyan, H; Hance, M; Hansen, J D; Hansen, P H; Hara, K; Harvey, A., Jr; Hawkings, R J; Heinemann, F E W; Henriques Correia, A; Henss, T; Hervas, L; Higon, E; Hill, J C; Hoffman, J; Hostachy, J Y; Hruska, I; Hubaut, F; Huegging, F; Hulsbergen, W; Hurwitz, M; Iconomidou-Fayard, L; Jansen, E; Jen-La Plante, I; Johansson, P D C; Jon-And, K; Joos, M; Jorgensen, S; Joseph, J; Kaczmarska, A; Kado, M; Karyukhin, A; Kataoka, M; Kayumov, F; Kazarov, A; Keener, P T; Kekelidze, G D; Kerschen, N; Kersten, S; Khomich, A; Khoriauli, G; Khramov, E; Khristachev, A; Khubua, J; Kittelmann, T H; Klingenberg, R; Klinkby, E B; Kodys, P; Koffas, T; Kolos, S; Konovalov, S P; Konstantinidis, N; Kopikov, S; Korolkov, I; Kostyukhin, V; Kovalenko, S; Kowalski, T Z; Krüger, K.; Kramarenko, V; Kudin, L G; Kulchitsky, Y; Lacasta, C; Lafaye, R; Laforge, B; Lampl, W; Lanni, F; Laplace, S; Lari, T; Le Bihan, A C; Lechowski, M; Ledroit-Guillon, F; Lehmann, G; Leitner, R; Lelas, D; Lester, C G; Liang, Z; Lichard, P; Liebig, W; Lipniacka, A; Lokajicek, M; Louchard, L; Lourerio, K F; Lucotte, A; Luehring, F; Lund-Jensen, B; Lundberg, B; Ma, H; Mackeprang, R; Maio, A; Maleev, V P; Malek, F; Mandelli, L; Maneira, J; Mangin-Brinet, M; Manousakis, A; Mapelli, L; Marques, C; Marti i Garcia, S; Martin, F; Mathes, M; Mazzanti, M; McFarlane, K W; McPherson, R; Mchedlidze, G; Mehlhase, S; Meirosu, C; Meng, Z; Meroni, C; Mialkovski, V; Mikulec, B; Milstead, D; Minashvili, I; Mindur, B; Mitsou, V A; Moed, S; Monnier, E; Moorhead, G; Morettini, P; Morozov, S V; Mosidze, M; Mouraviev, S V; Moyse, E W J; Munar, A; Myagkov, A; Nadtochi, A V; Nakamura, K; Nechaeva, P; Negri, A; Nemecek, S; Nessi, M; Nesterov, S Y; Newcomer, F M; Nikitine, I; Nikolaev, K; Nikolic-Audit, I; Ogren, H; Oh, S H; Oleshko, S B; Olszowska, J; Onofre, A; Padilla Aranda, C; Paganis, S; Pallin, D; Pantea, D; Paolone, V; Parodi, F; Parsons, J; Parzhitskiy, S; Pasqualucci, E; Passmored, S M; Pater, J; Patrichev, S; Peez, M; Perez Reale, V; Perini, L; Peshekhonov, V D; Petersen, J; Petersen, T C; Petti, R; Phillips, P W; Pina, J; Pinto, B; Podlyski, F; Poggioli, L; Poppleton, A; Poveda, J; Pralavorio, P; Pribyl, L; Price, M J; Prieur, D; Puigdengoles, C; Puzo, P; Røhne, O.; Ragusa, F; Rajagopalan, S; Reeves, K; Reisinger, I; Rembser, C; Bruckman de Renstrom, P A; Reznicek, P; Ridel, M; Risso, P; Riu, I; Robinson, D; Roda, C; Roe, S; Rohne, O; Romaniouk, A; Rousseau, D; Rozanov, A; Ruiz, A; Rusakovich, N; Rust, D; Ryabov, Y F; Ryjov, V; Salto, O; Salvachua, B; Salzburger, A; Sandaker, H; Santamarina Rios, C; Santi, L; Santoni, C; Saraiva, J G; Sarri, F; Sauvage, G; Says, L P; Schaefer, M; Schegelsky, V A; Schiavi, C; Schieck, J; Schlager, G; Schlereth, J; Schmitt, C; Schultes, J; Schwemling, P; Schwindling, J; Seixas, J M; Seliverstov, D M; Serin, L; Sfyrla, A; Shalanda, N; Shaw, C; Shin, T; Shmeleva, A; Silva, J; Simion, S; Simonyan, M; Sloper, J E; Smirnov, S.Yu; Smirnova, L; Solans, C; Solodkov, A; Solovianov, O; Soloviev, I; Sosnovtsev, V V; Spano, F; Speckmayer, P; Stancu, S; Stanek, R; Starchenko, E; Straessner, A; Suchkov, S I; Suk, M; Szczygiel, R; Tarrade, F; Tartarelli, F; Tas, P; Tayalati, Y; Tegenfeldt, F; Teuscher, R; Thioye, M; Tikhomirov, V O; Timmermans, C J W P; Tisserant, S; Toczek, B; Tremblet, L; Troncon, C; Tsiareshka, P; Tyndel, M; Karagoez Unel, M; Unal, G; Unel, G; Usai, G; Van Berg, R; Valero, A; Valkar, S; Valls, J A; Vandelli, W; Vannucci, F; Vartapetian, A; Vassilakopoulos, V I; Vasilyeva, L; Vazeille, F; Vernocchi, F; Vetter-Cole, Y; Vichou, I; Vinogradov, V; Virzi, J; Vivarelli, I; de Vivie, J B; Volpi, M; Vu Anh, T; Wang, C; Warren, M; Weber, J; Weber, M; Weidberg, A R; Weingarten, J; Wells, P S; Werner, P; Wheeler, S; Wiessmann, M; Wilkens, H; Williams, H H; Wingerter-Seez, I; Yasu, Y; Zaitsev, A; Zenin, A; Zenis, T; Zenonos, Z; Zhang, H; Zhelezko, A; Zhou, N

    2011-01-01

    A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of the calorimeter layer energy deposits, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20 and 180 GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by 11% to 25% compared to the response at the electromagnetic scale.

  8. A comparative study of CdS thin films deposited by different techniques

    International Nuclear Information System (INIS)

    Cadmium sulfide thin-films were deposited on glass slides and SnO2:F coated glass substrates by chemical bath deposition, sputtering and close-spaced sublimation techniques. The films were studied for the structural and opto-electronic properties after annealing in an ambient identical to that employed in the fabrication of CdTe/CdS devices. Quantum efficiency of the CdTe/CdS solar cells fabricated with CdS buffer films prepared by the three methods were investigated to understand the role of CdS film preparation method on the blue response of the devices. The higher blue response observed for the devices fabricated with chemical bath deposited CdS film is discussed. - Highlights: ► CdS films were prepared by different techniques. ► Role of CdS on the blue response of device was studied. ► Structural and optical properties of CdS were analyzed. ► Chemically deposited CdS has high blue transmittance. ► CdS deposition method influences diffusion of S and Te

  9. A comparative study of CdS thin films deposited by different techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pérez-Hernández, G., E-mail: german.perez@ujat.mx [Universidad Juárez Autónoma de Tabasco, Avenida Universidad s/n, Col. Magisterial, Villahermosa, Tabasco 86040 (Mexico); Pantoja-Enríquez, J. [Centro de Investigación y Desarrollo Tecnológico en Energías Renovables, UNICACH, Libramiento Norte No 1150, Tuxtla Gutiérrez, Chiapas 29039 (Mexico); Escobar-Morales, B. [Instituto Tecnológico de Cancún, Avenida Kábah Km 3, Cancún, Quintana Roo 77500 (Mexico); Martinez-Hernández, D.; Díaz-Flores, L.L.; Ricardez-Jiménez, C. [Universidad Juárez Autónoma de Tabasco, Avenida Universidad s/n, Col. Magisterial, Villahermosa, Tabasco 86040 (Mexico); Mathews, N.R.; Mathew, X. [Centro de Investigación en Energía, Universidad Nacional Autónoma de México, Temixco, Morelos 62580 (Mexico)

    2013-05-01

    Cadmium sulfide thin-films were deposited on glass slides and SnO{sub 2}:F coated glass substrates by chemical bath deposition, sputtering and close-spaced sublimation techniques. The films were studied for the structural and opto-electronic properties after annealing in an ambient identical to that employed in the fabrication of CdTe/CdS devices. Quantum efficiency of the CdTe/CdS solar cells fabricated with CdS buffer films prepared by the three methods were investigated to understand the role of CdS film preparation method on the blue response of the devices. The higher blue response observed for the devices fabricated with chemical bath deposited CdS film is discussed. - Highlights: ► CdS films were prepared by different techniques. ► Role of CdS on the blue response of device was studied. ► Structural and optical properties of CdS were analyzed. ► Chemically deposited CdS has high blue transmittance. ► CdS deposition method influences diffusion of S and Te.

  10. Characterisation of Pb thin films prepared by the nanosecond pulsed laser deposition technique for photocathode application

    International Nuclear Information System (INIS)

    Pb thin films were prepared by the nanosecond pulsed laser deposition technique on Si (100) and polycrystalline Nb substrates for photocathode application. As the photoemission performances of a cathode are strongly affected by its surface characteristics, the Pb films were grown at different substrate temperatures with the aim of modifying the morphology and structure of thin films. An evident morphological modification in the deposited films with the formation of spherical grains at higher temperatures has been observed. X-ray diffraction measurements showed that a preferred orientation of Pb (111) normal to the substrate was achieved at 30 °C while the Pb (200) plane became strongly pronounced with the increase in the substrate temperature. Finally, a Pb thin film deposited on Nb substrate at 30 °C and tested as the photocathode showed interesting results for the application of such a device in superconducting radio frequency guns. - Highlights: • Pb thin films obtained by the nanosecond pulsed laser deposition technique at different substrate temperature. • The substrate temperature modifies the morphology and structure of Pb films. • Pb thin film was deposited at room temperature for photocathode application. • The Pb thin film photocathode was tested and the quantum efficiency of the device improved after laser cleaning treatment of the film surface

  11. Comparison of SnO2/Si-n Thin Films Deposited by Pneumatic Spray Pyrolysis Technique with that Deposited by Ultrasonic Spray Pyrolysis Technique

    International Nuclear Information System (INIS)

    Pneumatic Spray Pyrolysis (PSP) technique has been generally used to grow low cost transparent conducting oxide/TCO films involving various interesting materials such as tin oxide/ SnO2, indium tin oxide/ITO and zinc oxide/ZnO. The PSP is widely acceptable because of its cost effectiveness, simple operation, easy doping etc. Since the emerging of ultrasonic spray pyrolysis (USP) technique, attention has been given more on this technique because of several advantageous over the PSP technique such as low pressure, lower consumption of source material, lower of overspray material so reduce the contamination around and also results in unclog nozzle. In this paper, we report the SnO2/Si-n thin films deposition using these two techniques by evaluate both parameter process (source materials, substrate temperature, requirement for catalyst chemicals etc.) and the resulted SnO2/Si-n thin film properties (structural, electrical and optical properties). We compare SnO2/Si-n best thin film samples obtained from both experiments under optimum experimental condition and evaluate them. In conclusion, the Ultrasonic Spray Pyrolysis technique, using the same quantity of source materials to grow the SnO2/Si-n thin film, results in same quality of tin oxide polycrystal with almost equal resistivity and homogeneity, need less consumption of source materials up to 80 %, lower required temperature (50 - 100) oC and simpler catalyst/less toxic compared with Pneumatic Spray Pyrolysis technique. The USP system here is being developed further to produce various thin films for energy devices (for example solar cell and fuel cell). (author)

  12. Differential deposition technique for figure corrections in grazing-incidence x-ray optics

    Science.gov (United States)

    Kilaru, Kiranmayee; Ramsey, Brian D.; Gubarev, Mikhail V.; Gregory, Don A.

    2011-10-01

    A differential deposition technique was investigated as a way to minimize axial figure errors in full-shell, grazing-incidence, reflective x-ray optics. These types of optics use a combination of off-axis conic segments--hyperbolic, parabolic, and/or elliptical, to reflect and image x-rays. Several such mirrors or ``shells'' of decreasing diameter are typically concentrically nested to form a single focusing unit. Individual mirrors are currently produced at Marshall Space Flight Center using an electroforming technique, in which the shells are replicated off figured and superpolished mandrels. Several factors in this fabrication process lead to low- and mid-spatial frequency deviations in the surface profile of the shell that degrade the imaging quality of the optics. A differential deposition technique, discussed in this paper, seeks to improve the achievable resolution of the optics by correcting the surface profile deviations of the shells after fabrication. As a proof of concept, the technique was implemented on small-animal radionuclide-imaging x-ray optics being considered for medical applications. This paper discusses the deposition technique, its implementation, and the experimental results obtained to date.

  13. Computational study of transport and energy deposition of intense laser-accelerated proton beams in solid density matter

    Science.gov (United States)

    Kim, J.; McGuffey, C.; Qiao, B.; Beg, F. N.; Wei, M. S.; Grabowski, P. E.

    2015-11-01

    With intense proton beams accelerated by high power short pulse lasers, solid targets are isochorically heated to become partially-ionized warm or hot dense matter. In this regime, the thermodynamic state of the matter significantly changes, varying the proton stopping power where both bound and free electrons contribute. Additionally, collective beam-matter interaction becomes important to the beam transport. We present self-consistent hybrid particle-in-cell (PIC) simulation results of proton beam transport and energy deposition in solid-density matter, where the individual proton stopping and the collective effects are taken into account simultaneously with updates of stopping power in the varying target conditions and kinetic motions of the beam in the driven fields. Broadening of propagation range and self-focusing of the beam led to unexpected target heating by the intense proton beams, with dependence on the beam profiles and target conditions. The behavior is specifically studied for the case of an experimentally measured proton beam from the 1.25 kJ, 10 ps OMEGA EP laser transporting through metal foils. This work was supported by the U.S. DOE under Contracts No. DE-NA0002034 and No. DE-AC52-07NA27344 and by the U.S. AFOSR under Contract FA9550-14-1-0346.

  14. Pulsed laser deposition: the road to hybrid nanocomposites coatings and novel pulsed laser adaptive technique.

    Science.gov (United States)

    Serbezov, Valery

    2013-01-01

    The applications of Pulsed Laser Deposition (PLD) for producing nanoparticles, nanostructures and nanocomposites coatings based on recently developed laser ablating techniques and their convergence are being reviewed. The problems of in situ synthesis of hybrid inorganic-organic nanocomposites coatings by these techniques are being discussed. The novel modification of PLD called Pulsed Laser Adaptive Deposition (PLAD) technique is presented. The in situ synthesized inorganic/organic nanocomposites coatings from Magnesium (Mg) alloy/Rhodamine B and Mg alloy/ Desoximetasone by PLAD are described. The trends, applications and future development of discussed patented methods based on the laser ablating technologies for producing hybrid nanocomposite coatings have also been discussed in this review. PMID:22747717

  15. An ultra-low energy (30-200 eV) ion-atomic beam source for ion-beam-assisted deposition in ultrahigh vacuum.

    Science.gov (United States)

    Mach, Jindrich; Samoril, Tomás; Voborný, Stanislav; Kolíbal, Miroslav; Zlámal, Jakub; Spousta, Jirí; Dittrichová, Libuse; Sikola, Tomás

    2011-08-01

    The paper describes the design and construction of an ion-atomic beam source with an optimized generation of ions for ion-beam-assisted deposition under ultrahigh vacuum (UHV) conditions. The source combines an effusion cell and an electron impact ion source and produces ion beams with ultra-low energies in the range from 30 eV to 200 eV. Decreasing ion beam energy to hyperthermal values (≈10(1) eV) without loosing optimum ionization conditions has been mainly achieved by the incorporation of an ionization chamber with a grid transparent enough for electron and ion beams. In this way the energy and current density of nitrogen ion beams in the order of 10(1) eV and 10(1) nA/cm(2), respectively, have been achieved. The source is capable of growing ultrathin layers or nanostructures at ultra-low energies with a growth rate of several MLs/h. The ion-atomic beam source will be preferentially applied for the synthesis of GaN under UHV conditions. PMID:21895238

  16. A Novel Catalyst Deposition Technique for the Growth of Carbon Nanotubes

    Science.gov (United States)

    Delzeit, Lance; Cassell, A.; Stevens, R.; Nguyen, C.; Meyyappan, M.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    This viewgraph presentation provides information on the development of a technique at NASA's Ames Research Center by which carbon nanotubes (NT) can be grown. The project had several goals which included: 1) scaleability, 2) ability to control single wall nanotube (SWNT) and multiwall nanotube (MWNT) formation, 3) ability to control the density of nanotubes as they grow, 4) ability to apply standard masking techniques for NT patterning. Information regarding the growth technique includes its use of a catalyst deposition process. SWNTs of varying thicknesses can be grown by changing the catalyst composition. Demonstrations are given of various methods of masking including the use of transmission electron microscopic (TEM) grids.

  17. Electrochemical characterization of NiO electrodes deposited via a scalable powder microblasting technique

    OpenAIRE

    Awais, Muhammad; Dini, Danilo; MacElroy, J. M. Don; Halpin, Yvonne; Vos, Johannes G.; Dowling, Denis P.

    2013-01-01

    In this contribution a novel powder coating processing technique (microblasting) for the fabrication of nickel oxide (NiOx) coatings is reported. ~1.2 μm thick NiOx coatings are deposited at 20 mm2 s−1 by the bombardment of the NiOx powder onto a Ni sheet using an air jet at a speed of more than 180 m s−1. Microblast deposited NiOx coatings can be prepared at a high processing rate, do not need further thermal treatment. Therefore, this scalable method is time and energy efficient. The mechan...

  18. Synthesis of carbon nanotubes using the cobalt nanocatalyst by thermal chemical vapor deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Madani, S.S. [Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Zare, K. [Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Department of Chemistry, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Ghoranneviss, M. [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Salar Elahi, A., E-mail: Salari_phy@yahoo.com [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2015-11-05

    The three main synthesis methods of Carbon nanotubes (CNTs) are the arc discharge, the laser ablation and the chemical vapour deposition (CVD) with a special regard to the latter one. CNTs were produced on a silicon wafer by Thermal Chemical Vapor Deposition (TCVD) using acetylene as a carbon source, cobalt as a catalyst and ammonia as a reactive gas. The DC-sputtering system was used to prepare cobalt thin films on Si substrates. A series of experiments was carried out to investigate the effects of reaction temperature and deposition time on the synthesis of the nanotubes. The deposition time was selected as 15 and 25 min for all growth temperatures. Energy Dispersive X-ray (EDX) measurements were used to investigate the elemental composition of the Co nanocatalyst deposited on Si substrates. Atomic Force Microscopy (AFM) was used to characterize the surface topography of the Co nanocatalyst deposited on Si substrates. The as-grown CNTs were characterized under Field Emission Scanning Electron Microscopy (FESEM) to study the morphological properties of CNTs. Also, the grown CNTs have been investigated by High Resolution Transmission Electron Microscopy (HRTEM) and Raman spectroscopy. The results demonstrated that increasing the temperature leads to increasing the diameter of CNTs. The ideal reaction temperature was 850 °C and the deposition time was 15 min. - Graphical abstract: FESEM images of CNTs grown on the cobalt catalyst at growth temperatures of (a) 850 °C, (b) 900 °C, (c) 950 °C and (d) 1000 °C during the deposition time of 15 min. - Highlights: • Carbon nanotubes (CNTs) were produced on a silicon wafer by TCVD technique. • EDX and AFM were used to investigate the elemental composition and surface topography. • FESEM was used to study the morphological properties of CNTs. • The grown CNTs have been investigated by HRTEM and Raman spectroscopy.

  19. Synthesis of carbon nanotubes using the cobalt nanocatalyst by thermal chemical vapor deposition technique

    International Nuclear Information System (INIS)

    The three main synthesis methods of Carbon nanotubes (CNTs) are the arc discharge, the laser ablation and the chemical vapour deposition (CVD) with a special regard to the latter one. CNTs were produced on a silicon wafer by Thermal Chemical Vapor Deposition (TCVD) using acetylene as a carbon source, cobalt as a catalyst and ammonia as a reactive gas. The DC-sputtering system was used to prepare cobalt thin films on Si substrates. A series of experiments was carried out to investigate the effects of reaction temperature and deposition time on the synthesis of the nanotubes. The deposition time was selected as 15 and 25 min for all growth temperatures. Energy Dispersive X-ray (EDX) measurements were used to investigate the elemental composition of the Co nanocatalyst deposited on Si substrates. Atomic Force Microscopy (AFM) was used to characterize the surface topography of the Co nanocatalyst deposited on Si substrates. The as-grown CNTs were characterized under Field Emission Scanning Electron Microscopy (FESEM) to study the morphological properties of CNTs. Also, the grown CNTs have been investigated by High Resolution Transmission Electron Microscopy (HRTEM) and Raman spectroscopy. The results demonstrated that increasing the temperature leads to increasing the diameter of CNTs. The ideal reaction temperature was 850 °C and the deposition time was 15 min. - Graphical abstract: FESEM images of CNTs grown on the cobalt catalyst at growth temperatures of (a) 850 °C, (b) 900 °C, (c) 950 °C and (d) 1000 °C during the deposition time of 15 min. - Highlights: • Carbon nanotubes (CNTs) were produced on a silicon wafer by TCVD technique. • EDX and AFM were used to investigate the elemental composition and surface topography. • FESEM was used to study the morphological properties of CNTs. • The grown CNTs have been investigated by HRTEM and Raman spectroscopy

  20. Spin-polarized radioactive isotope beam produced by tilted-foil technique

    Energy Technology Data Exchange (ETDEWEB)

    Hirayama, Yoshikazu, E-mail: yoshikazu.hirayama@kek.jp [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Mihara, Mototsugu [Department of Physics, Osaka University, Osaka 560-0043 (Japan); Watanabe, Yutaka; Jeong, Sun-Chan; Miyatake, Hiroari [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Momota, Sadao [Kochi University of Technology, Kochi 782-8502 (Japan); Hashimoto, Takashi; Imai, Nobuaki [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Matsuta, Kensaku [Department of Physics, Osaka University, Osaka 560-0043 (Japan); Ishiyama, Hironobu [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Ichikawa, Shin-ichi; Ishii, Tetsuro [Japan Atomic Energy Agency (JAEA), Ibaraki 319-1195 (Japan); Izumikawa, Takuji [Radioisotope Center, Niigata University, Niigata 951-8510 (Japan); Katayama, Ichiro; Kawakami, Hirokane [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Kawamura, Hirokazu [Department of Physics, Rikkyo University, Tokyo 171-8501 (Japan); Nishinaka, Ichiro; Nishio, Katsuhisa; Makii, Hiroyuki; Mitsuoka, Shin-ichi [Japan Atomic Energy Agency (JAEA), Ibaraki 319-1195 (Japan); and others

    2013-12-15

    Highlights: • Detail study for tilted foil technique. • New equation for estimating nuclear polarization dependence on the beam energy. • Production of nuclear polarization for heaviest nucleus {sup 123}In in ground state. -- Abstract: The tilted-foil method for producing spin-polarized radioactive isotope beams has been studied using the re-accelerated radioactive {sup 8}Li and {sup 123}In beams produced at Tokai Radioactive Ion Accelerator Complex (TRIAC) facility. We successfully produced polarization in a {sup 8}Li beam of 7.3(5)% using thin polystyrene foils (4.2 μg/cm{sup 2}). The systematic study of the nuclear polarization as a function of the number of foils and beam energy has been performed, confirming the features of the tilted-foil technique experimentally. After the study, a spin-polarized radioactive {sup 123}In beam, which is the heaviest ever polarized in its ground state by this method, has been successfully generated by the tilted-foil method, for the nuclear spectroscopy around the doubly magic nucleus {sup 132}Sn.

  1. Growth modes and epitaxy of FeAl thin films on a-cut sapphire prepared by pulsed laser and ion beam assisted deposition

    International Nuclear Information System (INIS)

    FeAl films around equiatomic composition are grown on a-cut (112¯0) sapphire substrates by ion beam assisted deposition (IBAD) and pulsed laser deposition (PLD) at ambient temperature. Subsequent successive annealing is used to establish chemical order and crystallographic orientation of the films with respect to the substrate. We find a strongly [110]-textured growth for both deposition techniques. Pole figures prove the successful preparation of high quality epitaxial films by PLD with a single in-plane orientation. IBAD-grown films, however, exhibit three in-plane orientations, all of them with broad angular distributions. The difference of the two growth modes is attributed to the existence of a metastable intermediate crystalline orientation as concluded from nonassisted sputter depositions at different substrate temperatures. The formation of the chemically ordered crystalline B2 phase is accompanied by the expected transition from ferromagnetic to paramagnetic behavior of the films. In accordance with the different thermally induced structural recovery, we find a step-like magnetic transition to paramagnetic behavior after annealing for 1 h at TA = 300 °C for IBAD deposition, while PLD-grown films show a gradual decrease of ferromagnetic signals with rising annealing temperatures

  2. Comparison of linear energy transfer scoring techniques in Monte Carlo simulations of proton beams

    International Nuclear Information System (INIS)

    Monte Carlo (MC) simulations are commonly used to study linear energy transfer (LET) distributions in therapeutic proton beams. Various techniques have been used to score LET in MC simulations. The goal of this work was to compare LET distributions obtained using different LET scoring techniques and examine the sensitivity of these distributions to changes in commonly adjusted simulation parameters. We used three different techniques to score average proton LET in TOPAS, which is a MC platform based on the Geant4 simulation toolkit. We determined the sensitivity of each scoring technique to variations in the range production thresholds for secondary electrons and protons. We also compared the depth-LET distributions that we acquired using each technique in a simple monoenergetic proton beam and in a more clinically relevant modulated proton therapy beam. Distributions of both fluence-averaged LET (LETΦ) and dose-averaged LET (LETD) were studied. We found that LETD values varied more between different scoring techniques than the LETΦ values did, and different LET scoring techniques showed different sensitivities to changes in simulation parameters. (note)

  3. Study of the growth of biaxially textured CeO2 films during ion-beam-assisted deposition

    International Nuclear Information System (INIS)

    Biaxially textured CeO2 films were deposited on Hastelloy C276 substrates at room temperature using ion-beam-assisted e-beam evaporation with the ion beam directed at 55 deg. to the normal of the film plane. The crystalline structure and in-plane orientation of films were investigated by x-ray diffraction 2θ-scan and φ-scan. The orientation of the films was studied as a function of ion-to-atom ratio and film thickness. The ion-to-atom ratio was varied by independently adjusting the deposition rate and the ion current density. Under optimum condition, (200) textured CeO2 films have been successfully grown on Hastelloy C276

  4. Study of the growth of biaxially textured CeO{sub 2} films during ion-beam-assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Su [Department of Metallurgical Engineering, Yonsei University, Seodaemoon Ku, Shinchon Dong 134, Seoul 120-749 (Korea, Republic of); Jo, Sung Jin [Department of Metallurgical Engineering, Yonsei University, Seodaemoon Ku, Shinchon Dong 134, Seoul 120-749 (Korea, Republic of); Jeong, Soon Moon [Department of Metallurgical Engineering, Yonsei University, Seodaemoon Ku, Shinchon Dong 134, Seoul 120-749 (Korea, Republic of); Kim, Woo Jin [Department of Metallurgical Engineering, Yonsei University, Seodaemoon Ku, Shinchon Dong 134, Seoul 120-749 (Korea, Republic of); Baik, Hong Koo [Department of Metallurgical Engineering, Yonsei University, Seodaemoon Ku, Shinchon Dong 134, Seoul 120-749 (Korea, Republic of); Lee, Se Jong [Department of Materials Science and Engineering, Kyungsung University, Busan 608-736 (Korea, Republic of); Song, Kie Moon [Department of Applied Physics, Konkuk University, Chungju 380-701 (Korea, Republic of)

    2005-03-01

    Biaxially textured CeO{sub 2} films were deposited on Hastelloy C276 substrates at room temperature using ion-beam-assisted e-beam evaporation with the ion beam directed at 55 deg. to the normal of the film plane. The crystalline structure and in-plane orientation of films were investigated by x-ray diffraction 2{theta}-scan and {phi}-scan. The orientation of the films was studied as a function of ion-to-atom ratio and film thickness. The ion-to-atom ratio was varied by independently adjusting the deposition rate and the ion current density. Under optimum condition, (200) textured CeO{sub 2} films have been successfully grown on Hastelloy C276.

  5. Study of the growth of biaxially textured CeO2 films during ion-beam-assisted deposition

    Science.gov (United States)

    Kim, Chang Su; Jo, Sung Jin; Jeong, Soon Moon; Kim, Woo Jin; Baik, Hong Koo; Lee, Se Jong; Song, Kie Moon

    2005-03-01

    Biaxially textured CeO2 films were deposited on Hastelloy C276 substrates at room temperature using ion-beam-assisted e-beam evaporation with the ion beam directed at 55° to the normal of the film plane. The crystalline structure and in-plane orientation of films were investigated by x-ray diffraction 2θ-scan and phgr-scan. The orientation of the films was studied as a function of ion-to-atom ratio and film thickness. The ion-to-atom ratio was varied by independently adjusting the deposition rate and the ion current density. Under optimum condition, (200) textured CeO2 films have been successfully grown on Hastelloy C276.

  6. Total body superficial electron beam therapy using a dual field technique

    International Nuclear Information System (INIS)

    A technique using a dual field is presented. This technique has applications in mycosis fungoides using superficial electron-beam with 8 MeV therapy. For the multiple-field irradiation with dual field technique, a six distribution setup is used with 8 MeV electron-beam disperes around the whole body surface 1 cm in depth for treatment of mycosis fungoides. Some of the physical aspects, dosimetory, loss of build-up, depth-dose shift and increasing braking radiation (bremsstrahlung) using multiple overlapping because of high energy for superficial whole-body irradiation therapy were discussed. The 6-field technique is the methods of choice for superficial whole-body treatment. (author)

  7. Indium-doped ZnO thin films deposited by the sol-gel technique

    International Nuclear Information System (INIS)

    Conducting and transparent indium-doped ZnO thin films were deposited on sodocalcic glass substrates by the sol-gel technique. Zinc acetate and indium chloride were used as precursor materials. The electrical resistivity, structure, morphology and optical transmittance of the films were analyzed as a function of the film thickness and the post-deposition annealing treatments in vacuum, oxygen or argon. The obtained films exhibited a (002) preferential growth in all the cases. Surface morphology studies showed that an increase in the films' thickness causes an increase in the grain size. Films with 0.18 μm thickness, prepared under optimal deposition conditions followed by an annealing treatment in vacuum showed electrical resistivity of 1.3 x 10-2 Ωcm and optical transmittance higher than 85%. These results make ZnO:In thin films an attractive material for transparent electrodes in thin film solar cells

  8. Thin Film Formation of Gallium Nitride Using Plasma-Sputter Deposition Technique

    Directory of Open Access Journals (Sweden)

    R. Flauta

    2003-06-01

    Full Text Available The formation of gallium nitride (GaN thin film using plasma-sputter deposition technique has beenconfirmed. The GaN film deposited on a glass substrate at an optimum plasma condition has shown x-raydiffraction (XRD peaks at angles corresponding to that of (002 and (101 reflections of GaN. The remainingmaterial on the sputtering target exhibited XRD reflections corresponding to that of bulk GaN powder. Toimprove the system’s base pressure, a new UHV compatible system is being developed to minimize theimpurities in residual gases during deposition. The sputtering target configuration was altered to allow themonitoring of target temperature using a molybdenum (Mo holder, which is more stable against Gaamalgam formation than stainless steel.

  9. Characterization of defects in hydrogenated amorphous silicon deposited on different substrates by capacitance techniques

    Energy Technology Data Exchange (ETDEWEB)

    Darwich, R., E-mail: rdarwich@aec.org.sy [Physics Department, Atomic Energy Commission of Syria, P. O. Box 6091, Damascus (Syrian Arab Republic); Roca i Cabarrocas, P. [Laboratoire de physique des interfaces et des couches minces, CNRS, Ecole Polytechnique, 91128 Palaiseau France (France)

    2011-06-01

    Hydrogenated amorphous silicon (a-Si:H) thin films deposited on crystalline silicon and Corning glass substrate were analyzed using different capacitance techniques. The distribution of localized states and some electronic properties were studied using the temperature, frequency and bias dependence of the Schottky barrier capacitance and deep level transient spectroscopy. Our results show that the distribution of the gap states depends on the type of substrate. We have found that the films deposited on c-Si substrate represent only one positively charged or prerelaxed neutral deep state and one interface state, while the films deposited on glass substrate have one interface state and three types of deep defect states, positively or prerelaxed neutral, neutral and negatively charged.

  10. Characterization of defects in hydrogenated amorphous silicon deposited on different substrates by capacitance techniques

    International Nuclear Information System (INIS)

    Hydrogenated amorphous silicon (a-Si:H) thin films deposited on crystalline silicon and Corning glass substrate were analyzed using different capacitance techniques. The distribution of localized states and some electronic properties were studied using the temperature, frequency and bias dependence of the Schottky barrier capacitance and deep level transient spectroscopy. Our results show that the distribution of the gap states depends on the type of substrate. We have found that the films deposited on c-Si substrate represent only one positively charged or pre relaxed neutral deep state and one interface state, while the films deposited on glass substrate have one interface state and three types of deep defect states, positively or pre relaxed neutral, neutral and negatively charged. (author)

  11. Characterization of defects in hydrogenated amorphous silicon deposited on different substrates by capacitance techniques

    International Nuclear Information System (INIS)

    Hydrogenated amorphous silicon (a-Si:H) thin films deposited on crystalline silicon and Corning glass substrate were analyzed using different capacitance techniques. The distribution of localized states and some electronic properties were studied using the temperature, frequency and bias dependence of the Schottky barrier capacitance and deep level transient spectroscopy. Our results show that the distribution of the gap states depends on the type of substrate. We have found that the films deposited on c-Si substrate represent only one positively charged or prerelaxed neutral deep state and one interface state, while the films deposited on glass substrate have one interface state and three types of deep defect states, positively or prerelaxed neutral, neutral and negatively charged.

  12. Three-dimensional microstructural characterization of bulk plutonium and uranium metals using focused ion beam technique

    Science.gov (United States)

    Chung, Brandon W.; Erler, Robert G.; Teslich, Nick E.

    2016-05-01

    Nuclear forensics requires accurate quantification of discriminating microstructural characteristics of the bulk nuclear material to identify its process history and provenance. Conventional metallographic preparation techniques for bulk plutonium (Pu) and uranium (U) metals are limited to providing information in two-dimension (2D) and do not allow for obtaining depth profile of the material. In this contribution, use of dual-beam focused ion-beam/scanning electron microscopy (FIB-SEM) to investigate the internal microstructure of bulk Pu and U metals is demonstrated. Our results demonstrate that the dual-beam methodology optimally elucidate microstructural features without preparation artifacts, and the three-dimensional (3D) characterization of inner microstructures can reveal salient microstructural features that cannot be observed from conventional metallographic techniques. Examples are shown to demonstrate the benefit of FIB-SEM in improving microstructural characterization of microscopic inclusions, particularly with respect to nuclear forensics.

  13. Application of real-time digitization techniques in beam measurement for accelerators

    Science.gov (United States)

    Zhao, Lei; Zhan, Lin-Song; Gao, Xing-Shun; Liu, Shu-Bin; An, Qi

    2016-04-01

    Beam measurement is very important for accelerators. In this paper, modern digital beam measurement techniques based on IQ (In-phase & Quadrature-phase) analysis are discussed. Based on this method and high-speed high-resolution analog-to-digital conversion, we have completed three beam measurement electronics systems designed for the China Spallation Neutron Source (CSNS), Shanghai Synchrotron Radiation Facility (SSRF), and Accelerator Driven Sub-critical system (ADS). Core techniques of hardware design and real-time system calibration are discussed, and performance test results of these three instruments are also presented. Supported by National Natural Science Foundation of China (11205153, 10875119), Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-YW-N27), and the Fundamental Research Funds for the Central Universities (WK2030040029),and the CAS Center for Excellence in Particle Physics (CCEPP).

  14. Direct growth of Ge quantum dots on a graphene/SiO2/Si structure using ion beam sputtering deposition.

    Science.gov (United States)

    Zhang, Z; Wang, R F; Zhang, J; Li, H S; Zhang, J; Qiu, F; Yang, J; Wang, C; Yang, Y

    2016-07-29

    The growth of Ge quantum dots (QDs) using the ion beam sputtering deposition technique has been successfully conducted directly on single-layer graphene supported by SiO2/Si substrate. The results show that the morphology and size of Ge QDs on graphene can be modulated by tuning the Ge coverage. Charge transfer behavior, i.e. doping effect in graphene has been demonstrated at the interface of Ge/graphene. Compared with that of traditional Ge dots grown on Si substrate, the positions of both corresponding photoluminescence (PL) peaks of Ge QDs/graphene hybrid structure undergo a large red-shift, which can probably be attributed to the lack of atomic intermixing and the existence of surface states in this hybrid material. According to first-principles calculations, the Ge growth on the graphene should follow the so-called Volmer-Weber mode instead of the Stranski-Krastanow one which is observed generally in the traditional Ge QDs/Si system. The calculations also suggest that the interaction between Ge and graphene layer can be enhanced with the decrease of the Ge coverage. Our results may supply a prototype for fabricating novel optoelectronic devices based on a QDs/graphene hybrid nanostructure. PMID:27302495

  15. Direct growth of Ge quantum dots on a graphene/SiO2/Si structure using ion beam sputtering deposition

    Science.gov (United States)

    Zhang, Z.; Wang, R. F.; Zhang, J.; Li, H. S.; Zhang, J.; Qiu, F.; Yang, J.; Wang, C.; Yang, Y.

    2016-07-01

    The growth of Ge quantum dots (QDs) using the ion beam sputtering deposition technique has been successfully conducted directly on single-layer graphene supported by SiO2/Si substrate. The results show that the morphology and size of Ge QDs on graphene can be modulated by tuning the Ge coverage. Charge transfer behavior, i.e. doping effect in graphene has been demonstrated at the interface of Ge/graphene. Compared with that of traditional Ge dots grown on Si substrate, the positions of both corresponding photoluminescence (PL) peaks of Ge QDs/graphene hybrid structure undergo a large red-shift, which can probably be attributed to the lack of atomic intermixing and the existence of surface states in this hybrid material. According to first-principles calculations, the Ge growth on the graphene should follow the so-called Volmer–Weber mode instead of the Stranski–Krastanow one which is observed generally in the traditional Ge QDs/Si system. The calculations also suggest that the interaction between Ge and graphene layer can be enhanced with the decrease of the Ge coverage. Our results may supply a prototype for fabricating novel optoelectronic devices based on a QDs/graphene hybrid nanostructure.

  16. A Review: Welding Of Dissimilar Metal Alloys by Laser Beam Welding & Friction Stir Welding Techniques

    OpenAIRE

    Ms. Deepika Harwani; Mr. Kapil Banker

    2014-01-01

    Welding of dissimilar metals has attracted attention of the researchers worldwide, owing to its many advantages and challenges. There is no denial in the fact that dissimilar welded joints offer more flexibility in the design and production of the commercial and industrial components. Many welding techniques have been analyzed to join dissimilar metal combinations. The objective of this paper is to review two such techniques – Laser welding and Friction stir welding. Laser beam we...

  17. Characterization of the Plasma Edge for Technique of Atomic Helium Beam in the CIEMAT Fusion Device

    International Nuclear Information System (INIS)

    In this report, the measurement of Electron Temperature and Density in the Boundary Plasma of TJ-II with a Supersonic Helium Beam Diagnostic and work devoted to the upgrading of this technique are described. Also, simulations of Laser Induced Fluorescence (LIF) studies of level populations of electronically excited He atoms are shown. This last technique is now being installed in the CIEMAT fusion device. (Author )

  18. Joining of high temperature refractory alloys by electron beam welding technique

    International Nuclear Information System (INIS)

    High temperature refractory alloys, due to their high melting point and poor oxidation resistance, need a special welding technique which is capable of melting and simultaneously joining them without being contaminated by interstitial impurities. In the present study, joining of TZM alloy was studied by electron beam welding (EBW) technique. Welding parameters such as accelerating voltage, current and speed of welding were varied to achieve good quality weld joint. Optical characterization and microhardness evaluation were carried out on the weld material. (author)

  19. Structure and electrical properties of quaternary Cr–Si–Ni–W films prepared by ion beam sputter deposition

    International Nuclear Information System (INIS)

    Highlights: • Quaternary Cr–Si–Ni–W thin film was prepared by IBSD. • As-deposited Cr–Si–Ni–W films show nanocrystalline state in XRD analysis. • Big massive particles in Cr–Si–Ni–W films are mainly formed in deposition process. • Conduction mechanism was discussed based on microscopic analysis. - Abstract: Si-rich Cr–Si–Ni–W films were deposited by ion beam sputter deposition (IBSD) using a mother alloy target on polished Al2O3 substrates. Effects of ion beam voltage, annealing temperature and deposition time on sheet resistance and TCR of Cr–Si–Ni–W films were studied. Experimental results reveal that the as-deposited Cr–Si–Ni–W films obtained by IBSD show a crystalline state because of a high mobility of deposition atoms and molecules with more energy obtained from high energy ions. XRD and AFM analysis show that the big massive particles mainly composed of Si and CrSi2 in Cr–Si–Ni–W films are formed in the process of IBSD rather than in post-annealing stage. Long deposition time is significantly important to a decrease of the number and size of gaps between big particles in Cr–Si–Ni–W films and to an improvement of the continuity and compactness of film structure, influencing resistivity and TCR of deposition film. The conduction mechanism was discussed based on microscopic analysis and the conductive model proposed for Cr–Si–Ni–W films mainly composed of big particles

  20. Excellent crystalline silicon surface passivation by amorphous silicon irrespective of the technique used for chemical vapor deposition

    NARCIS (Netherlands)

    Schuttauf, J.A.; van der Werf, C.H.M.; Kielen, I.M.; van Sark, W.G.J.H.M.; Rath, J.K.; Schropp, R.E.I.

    2011-01-01

    Crystalline silicon surface passivation by amorphous silicon deposited by three different chemical vapor deposition (CVD) techniques at low (T ∼ 130 °C) temperatures is compared. For all three techniques, surface recombination velocities (SRVs) are reduced by two orders of magnitude after prolonged

  1. CdS thin films growth by ammonia free chemical bath deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Jaber, A.Y.; Alamri, S.N.; Aida, M.S., E-mail: aida_salah2@yahoo.fr

    2012-02-29

    Cadmium Sulfide CdS thin films were deposited by chemical bath deposition technique using ethanolamine as complexing agent instead of commonly used ammonia to avoid its toxicity and volatility during film preparation. In order to investigate the film growth mechanism samples were prepared with different deposition times. A set of substrates were dropped in the same bath and each 30 minutes a sample is withdrawn from the bath, by this way all the obtained films were grown in the same condition. The films structure was analyzed by X rays diffraction. In early stage of growth the obtained films are amorphous, with increasing the deposition time, the films exhibits a pure hexagonal structure with (101) preferential orientation. The film surface morphology was studied by atomic force microscopy. From these observations we concluded that the early growth stage starts in the 3D Volmer-Weber mode, followed by a transition to the Stransky-Krastanov mode with increasing deposition time. The critical thickness of this transition is 120 nm. CdS quantum dots were formed at end of the film growth. The optical transmittance characterization in the UV-Visible range shows that the prepared films have a high transparency ranging from 60 to 80% for photons having wavelength greater than 600 nm. - Highlights: Black-Right-Pointing-Pointer CdS thin films are deposited by ammonia-free chemical bath deposition. Black-Right-Pointing-Pointer Films have hexagonal structure with (101) preferential orientation. Black-Right-Pointing-Pointer Growth begins in the Volmer-Weber mode and changes to the Stransky-Krastanov mode. Black-Right-Pointing-Pointer CdS quantum dots are formed in the late stage of growth.

  2. Lipase immobilization for catalytic applications obtained using fumed silica deposited with MAPLE technique

    Science.gov (United States)

    Bloisi, Francesco; Califano, Valeria; Perretta, Giuseppe; Nasti, Libera; Aronne, Antonio; Di Girolamo, Rocco; Auriemma, Finizia; De Rosa, Claudio; Vicari, Luciano R. M.

    2016-06-01

    Lipases are enzymes used for catalyzing reactions of acylglycerides in biodiesel production from lipids, where enzyme immobilization on a substrate is required. Silica nanoparticles in different morphologies and configurations are currently used in conjunction with biological molecules for drug delivery and catalysis applications, but up to date their use for triglycerides has been limited by the large size of long-chain lipid molecules. Matrix assisted pulsed laser evaporation (MAPLE), a laser deposition technique using a frozen solution/suspension as a target, is widely used for deposition of biomaterials and other delicate molecules. We have carried out a MAPLE deposition starting from a frozen mixture containing fumed silica and lipase in water. Deposition parameters were chosen in order to increase surface roughness and to promote the formation of complex structures. Both the target (a frozen thickened mixture of nanoparticles/catalyst in water) and the deposition configuration (a small target to substrate distance) are unusual and have been adopted in order to increase surface contact of catalyst and to facilitate access to long-chain molecules. The resulting innovative film morphology (fumed silica/lipase cluster level aggregation) and the lipase functionality (for catalytic biodiesel production) have been studied by FESEM, FTIR and transesterification tests.

  3. Photoelectric response of thiamonomethinecyanine J-aggregate nanoribbons deposited via dielectrophoresis technique

    International Nuclear Information System (INIS)

    Different dyes can produce the two-dimensional self-assembled structures called J- and H-aggregates that make them attractive material for various nano-electronics applications. This paper shows that electrokinetic deposition technique of cyanine dye J-aggregates is appropriate for the photoelectric devices production. The influence of excitation in visible on conductivity is observed in J-aggregate channel structure deposited using dielectrophoresis technique. The effect was observed in self-assembled thiamonomethinecyanine nanostructures. Samples were analyzed using AFM and micro-Raman spectroscopy methods. Analysis shows that photoelectric response must be the result of conductive channel formation in the structure of J-aggregate between the electrodes. The observed increase in conductivity manifold exceeds the structure dark conductivity: maximal increase comprised 6.3 times.

  4. Photoelectric response of thiamonomethinecyanine J-aggregate nanoribbons deposited via dielectrophoresis technique

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, I.V.; Bobrinetskiy, I.I. [National Research University of Electronic Technology (MIET), Bld. 5, Pas. 4806, 124498, Zelenograd, Moscow (Russian Federation); Shapiro, B.I. [Lomonosov Moscow State University of Fine Chemical Technologies, Prospekt Vernadskogo, 86, 119571, Moscow (Russian Federation); Romashkin, A.V.; Nevolin, V.K. [National Research University of Electronic Technology (MIET), Bld. 5, Pas. 4806, 124498, Zelenograd, Moscow (Russian Federation)

    2014-01-10

    Different dyes can produce the two-dimensional self-assembled structures called J- and H-aggregates that make them attractive material for various nano-electronics applications. This paper shows that electrokinetic deposition technique of cyanine dye J-aggregates is appropriate for the photoelectric devices production. The influence of excitation in visible on conductivity is observed in J-aggregate channel structure deposited using dielectrophoresis technique. The effect was observed in self-assembled thiamonomethinecyanine nanostructures. Samples were analyzed using AFM and micro-Raman spectroscopy methods. Analysis shows that photoelectric response must be the result of conductive channel formation in the structure of J-aggregate between the electrodes. The observed increase in conductivity manifold exceeds the structure dark conductivity: maximal increase comprised 6.3 times.

  5. A Precious Metal-Free Electroless Technique for the Deposition of Copper on Carbon Fibers

    Science.gov (United States)

    Che, Dehui; Yao, Guangchun; Cao, Zhuokun

    2012-11-01

    This article introduces a new technique of electroless copper deposition on carbon fibers in the absence of precious metal as the catalyst. Copper layers were electrolessly deposited on the surface of carbon fiber without using the conventional palladium or silver catalyst to initiate redox reactions leading to metallization. This new technique shows that nickel seeds can serve as excellent catalysts to expedite the redox reactions. By performing experiments, parameters such as activation temperature, nickel ion concentration, and pH value were optimized, and an orbicular copper plating layer of carbon fiber was obtained in the copper sulfate salt-based conventional electroless solution. The surface morphology of copper coating was characterized by scanning electron microscopy and X-ray diffraction. The results indicate that uniform and smooth copper coating could be obtained by the new precious-metal free activation process. The resulting copper coating thickness is about 1 μm.

  6. Deposit subscribe Prediction using Data Mining Techniques based Real Marketing Dataset

    Science.gov (United States)

    Abbas, Safia

    2015-01-01

    Recently, economic depression, which scoured all over the world, affects business organizations and banking sectors. Such economic pose causes a severe attrition for banks and customer retention becomes impossible. Accordingly, marketing managers are in need to increase marketing campaigns, whereas organizations evade both expenses and business expansion. In order to solve such riddle, data mining techniques is used as an uttermost factor in data analysis, data summarizations, hidden pattern discovery, and data interpretation. In this paper, rough set theory and decision tree mining techniques have been implemented, using a real marketing data obtained from Portuguese marketing campaign related to bank deposit subscription [Moro et al., 2011]. The paper aims to improve the efficiency of the marketing campaigns and helping the decision makers by reducing the number of features, that describes the dataset and spotting on the most significant ones, and predict the deposit customer retention criteria based on potential predictive rules.

  7. Amorphous solar cells, the micromorph concept and the role of VHF-GD deposition technique

    OpenAIRE

    Meier, Johannes; Kroll, U.; Vallat-Sauvain, Evelyne; Spitznagel, J.; U. Graf; Shah, Arvind

    2008-01-01

    During the last two decades, the Institute of Microtechnology (IMT) has contributed in two important fields to future thin-film silicon solar cell processing and design: (1) In 1987, IMT introduced the so-called “very high frequency glow discharge (VHF-GD)” technique, a method that leads to a considerable enhancement in the deposition rate of amorphous and microcrystalline silicon layers. As a direct consequence of reduced plasma impedances at higher plasma excitation frequencies, silane dis...

  8. Fabrication of nano-structured TiO2 coatings using a microblast deposition technique

    OpenAIRE

    McDonnell, Kevin; English, Niall J.; Stallard, Charlie P.; et al.

    2013-01-01

    Micron thick titanium dioxide (TiO2) coatings exhibiting a nano-structured, anatase, meso-porous structure were successfully deposited across a range of polymer, conductive glass and metallic substrates at low velocities using a microblasting technique. This process was conducted at atmospheric pressure using compressed air as the carrier gas and commercially available agglomerated nano particles of TiO2 as the feedstock. An examination of the effect of impact kinetics on the agglomerated pow...

  9. The Influence of Various Deposition Techniques on the Photoelectrochemical Properties of the Titanium Dioxide Thin Fil

    Czech Academy of Sciences Publication Activity Database

    Morozová, Magdalena; Klusoň, Petr; Dzik, P.; Veselý, M.; Baudyš, M.; Krýsa, J.; Šolcová, Olga

    2013-01-01

    Roč. 65, č. 3 (2013), s. 452-458. ISSN 0928-0707 R&D Projects: GA TA ČR TA01020804 Grant ostatní: GA ČR(CZ) GP104/09/P165 Institutional support: RVO:67985858 Keywords : titanium dioxide * photoelectrochemical properties * deposition techniques Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.547, year: 2013

  10. Fabrication of multiferroic GdMnO3 thin film by pulsed laser deposition technique

    Science.gov (United States)

    Negi, Puneet; Agrawal, H. M.; Srivastava, R. C.; Asokan, K.

    2012-06-01

    Here, we report the fabrication of GdMnO3 multiferroic thin film on SrTiO3 (110) substrate by pulsed laser deposition (PLD) technique. The target sample was synthesized using modified solgel route. The thickness of the film observed by Talystep profilometer, is about 200 nm. X-ray diffraction and Raman spectroscopic techniques were used to investigate the structure of the target as well as of the film. The surface topography of the film was investigated by atomic force microscopy.

  11. Ion exchange blinding-preventing technique of in-situ uranium leaching in Qianerkuai uranium deposit

    International Nuclear Information System (INIS)

    Qianerkuai uranium deposit contains high carbonates and rich clay. It is a low penetrability sandstone uranium ore which can be exploited by in-situ leaching technique. During the pilot production, the blinding phenomena occurred because of its low penetrability. According to the in-situ uranium leaching mechanism, the 001 x 7 cation exchange resin was selected to remove Ca2+ and Mg2+ from the injection liquid, which are the main cations to form the precipitation. The experiment results show that the removal effect of Ca2+ and Mg2+ is excellent. This technique can be applied in in-situ leaching of uranium. (authors)

  12. Studies on non-oxide coating on carbon fibers using plasma enhanced chemical vapor deposition technique

    Science.gov (United States)

    Patel, R. H.; Sharma, S.; Prajapati, K. K.; Vyas, M. M.; Batra, N. M.

    2016-05-01

    A new way of improving the oxidative behavior of carbon fibers coated with SiC through Plasma Enhanced Chemical Vapor Deposition technique. The complete study includes coating of SiC on glass slab and Stainless steel specimen as a starting test subjects but the major focus was to increase the oxidation temperature of carbon fibers by PECVD technique. This method uses relatively lower substrate temperature and guarantees better stoichiometry than other coating methods and hence the substrate shows higher resistance towards mechanical and thermal stresses along with increase in oxidation temperature.

  13. Synthesis of nanocrystalline silicon thin films using the increase of the deposition pressure in the hot-wire chemical vapour deposition technique

    Directory of Open Access Journals (Sweden)

    J.K. Rath

    2010-01-01

    Full Text Available Nanostructured thin silicon-based films have been deposited using the hot-wire chemical vapour deposition (HWCVD technique at the University of the Western Cape. A variety of techniques including optical and infrared spectroscopy, Raman scattering spectroscopy, X-rays diffraction (XRD and transmission electron microscopy (TEM have been used for characterisation of the films. The electrical measurements show that the films have good values of photoresponse, and the photocurrent remains stable after several hours of light soaking. This contribution will discuss the characteristics of the hydrogenated nanocrystalline silicon thin films deposited using increased process chamber pressure at a fixed hydrogen dilution ratio in monosilane gas.

  14. Mossbauer investigation of Fe1-x Crx films grown by ion-beam sputter deposition

    International Nuclear Information System (INIS)

    Fe1-xCrx (02 substrates were prepared using ion-beam sputter deposition, and their structural properties were determined by 57Fe conversion electron Mossbauer spectroscopy (CEMS) and X-ray diffraction experiments (XRD) at room temperature. CEM spectra show magnetic ordering for 0< x=<0.28, and the BCC α-phase is evidenced through XRD diagrams in all cases. The general trend for the films is that the average hyperfine magnetic field (HMF) values are lower compared to bulk counterparts. Moreover, a parabolic change in average HMF with Cr content x could be established. For 0.32=< x<0.70, the CEM spectra exhibit a pseudo-single line, which denotes paramagnetic state. Between x=0.32 and x=0.38, there exists a multiphase region where the alloys mainly consist of α and δ (A15-type) phases. Then, in the concentration range x=0.38-0.58, the films only display the metastable δ-phase. For 0.58=< x=<0.66, there appears a new transition region where α- and δ-phases coexist. Finally, the domain of the paramagnetic α-phase alone stretches from x=0.66 to at least x=0.70. Emphasis is placed on the metastable δ-phase which appears over a wide monophase region. Particularly, the site occupancy could be determined through the CEM spectrum for x=0.49

  15. Optical properties of ion-beam-deposited ion-modified diamondlike (a-C:H) carbon

    International Nuclear Information System (INIS)

    Diamondlike carbon (DLC) is a hard, semitransparent material usually containing varying amounts of hydrogen. These materials have numerous potential applications, including use as coatings for infrared optics, and as such, the effects of damaging irradiation is of practical interest. In this paper we present results of variable angle spectroscopic ellipsometric (VASE) studies of ion-beam-deposited DLC films. These films have been further modified by directing 1-MeV gold ions, as well as 6.4-MeV fluorine ions, through the DLC and into the underlying silicon substrates, and the percentage of hydrogen in the film was measured versus fluence using proton recoil analysis. Optical analysis was performed assuming the Lorentz oscillator model. Three versions were used: one oscillator, two oscillator (with one fixed in energy), and two oscillator with all parameter variable. The latter model fits the VASE data extremely well, and the two oscillators can be interpreted as involving π to π* and σ to σ* band transitions. With ion modification the oscillators shift to lower photon energy, consistent with reduction in hydrogen concentration and possible increased graphitization

  16. Tribological coatings for complex mechanical elements produced by supersonic cluster beam deposition of metal dichalcogenide nanoparticles

    International Nuclear Information System (INIS)

    Fullerene-like MoS2 and WS2 nanoparticles can be used as building blocks for the fabrication of fluid and solid lubricants. Metal dichalcogenide films have a very low friction coefficient in vacuum, therefore they have mostly been used as solid lubricants in space and vacuum applications. Unfortunately, their use is significantly hampered by the fact that in the presence of humidity, oxygen and moisture, the low-friction properties of these materials rapidly degrade due to oxidation. The use of closed-cage MoS2 and WS2 nanoparticles may eliminate this problem, although the fabrication of lubricant thin films starting from dichalcogenide nanoparticles is, to date, a difficult task. Here we demonstrate the use of supersonic cluster beam deposition for the coating of complex mechanical elements (angular contact ball bearings) with nanostructured MoS2 and WS2 thin films. We report structural and tribological characterization of the coatings in view of the optimization of tribological performances for aerospace applications. (paper)

  17. Electrochemical characteristics of CrN thin films prepared by ion-beam-enhanced deposition

    International Nuclear Information System (INIS)

    It has been known that CrN has high hardness and high resistance against wear, oxidation and corrosion. Although many studies have been done on its mechanical and high temperature oxidation properties, studies on its electrochemical and corrosion properties in aqueous solutions are still limited. The aim of this study is to produce CrN thin films by ion-beam-enhanced deposition (IBED) and to make clear the corrosion behavior of CrN by electrochemical measurements. CrN thin films were prepared by IBED under various conditions and their polarization curves were measured in 1 kmol·m-3 H2SO4 and 12 kmol·m-3 HCl. Changes in the surface of the thin films by polarization were examined by XPS and in-situ ellipsometry. The thin films prepared by IBED were composed of the large amount of CrN and small amounts of Cr2N and Cr. The fraction of CrN in the films increased with increasing flow rate of nitrogen. Potentiodynamic polarization curves exhibited that the active dissolution rate of the films decreased with increasing CrN content of the films. The films with high CrN content showed excellent corrosion resistance up to the start potential of transpassive dissolution without formation of passive films. That is, the excellent corrosion resistance of CrN results from the intrinsic inactive nature of CrN surface. (author)

  18. Tribological coatings for complex mechanical elements produced by supersonic cluster beam deposition of metal dichalcogenide nanoparticles

    Science.gov (United States)

    Piazzoni, C.; Buttery, M.; Hampson, M. R.; Roberts, E. W.; Ducati, C.; Lenardi, C.; Cavaliere, F.; Piseri, P.; Milani, P.

    2015-07-01

    Fullerene-like MoS2 and WS2 nanoparticles can be used as building blocks for the fabrication of fluid and solid lubricants. Metal dichalcogenide films have a very low friction coefficient in vacuum, therefore they have mostly been used as solid lubricants in space and vacuum applications. Unfortunately, their use is significantly hampered by the fact that in the presence of humidity, oxygen and moisture, the low-friction properties of these materials rapidly degrade due to oxidation. The use of closed-cage MoS2 and WS2 nanoparticles may eliminate this problem, although the fabrication of lubricant thin films starting from dichalcogenide nanoparticles is, to date, a difficult task. Here we demonstrate the use of supersonic cluster beam deposition for the coating of complex mechanical elements (angular contact ball bearings) with nanostructured MoS2 and WS2 thin films. We report structural and tribological characterization of the coatings in view of the optimization of tribological performances for aerospace applications.

  19. Synthesis of MoSi2 by energetic molybdenum cluster beam deposited on monocrystalline silicon at room temperature

    International Nuclear Information System (INIS)

    Mon- cluster beam was produced by a new type magnetron sputter gas aggregation cluster source. The beam was accelerated by the voltage of 0, 1, 3, 5, 10 kV and deposited onto polished p-type Si(111) substrate surface at room temperature, respectively, and then the thin film samples of Mo/Si(111) were prepared. X-ray diffraction analysis showed that there was no MoSi2 thin film formation in the area interface of Mo/Si(111) samples deposited by using both regular magnetron sputter and new type cluster source when the accelerated voltage was no more than 5 kV, whereas at the voltage of about 10 kV, there was MoSi2 thin film formed in the area interface of Mo/Si(111) samples deposited by using the new type cluster source. Only for the accelerated voltage higher than a threshold voltage (≥3 kV in this experiment), can the (110) oriented Mo thin film by the cluster beam deposition grow up. (authors)

  20. Focused-electron-beam-induced deposition of freestanding three-dimensional nanostructures of pure coalesced copper crystals

    International Nuclear Information System (INIS)

    We report on direct writing of three-dimensional freestanding nanostructures of Cu by use of a focused electron beam (FEB) and the metalorganic precursor hfac-Cu-TMVS. Freestanding horizontal rods were deposited over about 10 μm length and consist of small 2-5 nm Cu nanocrystals dispersed in an amorphous matrix containing carbon, fluorine, silicon, and oxygen. The freestanding horizontal rods were used as support for further vertical deposits resulting in tips of coalesced facetted Cu nanocrystals of up to 100 nm in size. The almost constant deposition rate of 5-6 nm/s is in contrast to vertical tips on bulk supports, which show a deposition rate decreasing from 23 to 10 nm/s. The above results suggest a thermal decomposition process induced by electron energy absorption

  1. Introduction to analytical techniques of beam-target interactions and resolutions

    International Nuclear Information System (INIS)

    For several years, new analysis and observation techniques have been developed, which have considerably improved material research. Almost all these techniques are based on the interaction of a beam of 'primary particles' (electrons, photons, ions, particles, etc) with target. Correct and appropriate use of these techniques requires a good knowledge of these interactions and their consequences (emissions of 'secondary particles', modifications of the primary beam and target, etc). The first part of this report deals with the radiation/material interactions according to the nature of the radiation and its energy. The nature and consequences of the interaction of an electromagnetic wave, a beam of electrons, ions and neutrons are examined over an extended range of energy from MeV to MeV. Certain notions such as the analysis area, spatial resolutions or limits of detection can also be defined. In the second part, some of the most important and widespread techniques of analysis and observation are compared in terms of properties and performance. In particular, there is a brief principle of the technique, nature of the data obtained, spatial resolution, and the limits of detection with today's methods permit. (author). 5 refs., 23 figs., 9 tabs

  2. Optical properties of organic films, multilayers and plasmonic metal-organic waveguides fabricated by organic molecular beam deposition

    Science.gov (United States)

    Wickremasinghe, Niranjala D.

    In this thesis, the optical properties of tris (8-hydroxyquinoline) aluminum (Alq3) and 3,5,9,10-perylentetracarboxylic dianhydride (PTCDA) organic films, PTCDA/ Alq3 multilayers and plasmonic Alq3 -metal waveguides are investigated. The organic films and heterostructures used for this work were fabricated by organic molecular beam deposition (OMBD). We investigated the quenching of the light emission in Alq3 films grown on a Si substrate as a function of cw laser excitation intensity at varying temperatures from 15 to 300 K. The saturation of the singlet-singlet annihilation coefficient was measured with spectrally-integrated (SI) photoluminescence (PL) using a photodiode. The bimolecular quenching coefficient was further studied with time-resolved (TR) PL as a function of 100 fs pulse fluences. The PL quenching is attributed to the annihilation of trapped excitons at Alq3 nanocrystal grain boundaries. The saturation is explained by the limited density of available trapping states at the grain boundaries. Our interpretation is supported by structural investigations of ultrathin Alq3 films with atomic force microscopy (AFM), scanning electron microscopy (SEM) and by comparing the experimental data with calculations using a coupled rate equation model. The wavelength dispersion of the refractive indices of PTCDA and Alq 3 layers and of PTCDA/Alq3 multilayer waveguides grown on Pyrex substrates was investigated. The m-line technique, an evanescent prism coupling technique, was used to determine the layers' thickness and the in-plane (TE modes) and normal (TM modes) refractive indices. The potential for controlling the refractive index dispersion and anisotropy by tailored organic multilayer waveguides is discussed.

  3. Practical Framework for an Electron Beam Induced Current Technique Based on a Numerical Optimization Approach

    Science.gov (United States)

    Yamaguchi, Hideshi; Soeda, Takeshi

    2015-03-01

    A practical framework for an electron beam induced current (EBIC) technique has been established for conductive materials based on a numerical optimization approach. Although the conventional EBIC technique is useful for evaluating the distributions of dopants or crystal defects in semiconductor transistors, issues related to the reproducibility and quantitative capability of measurements using this technique persist. For instance, it is difficult to acquire high-quality EBIC images throughout continuous tests due to variation in operator skill or test environment. Recently, due to the evaluation of EBIC equipment performance and the numerical optimization of equipment items, the constant acquisition of high contrast images has become possible, improving the reproducibility as well as yield regardless of operator skill or test environment. The technique proposed herein is even more sensitive and quantitative than scanning probe microscopy, an imaging technique that can possibly damage the sample. The new technique is expected to benefit the electrical evaluation of fragile or soft materials along with LSI materials.

  4. Thermal diffusivity measurements using a pulsed dual-beam thermal lens technique

    Science.gov (United States)

    Gupta, M. C.; Hong, S.-D.; Gupta, A.; Moacanin, J.

    1980-01-01

    A novel pulsed dual-beam thermal lens technique for the determination of thermal diffusivity of liquids and solids was developed. In this technique a transient thermal lens is formed in the test specimen by using a dye laser pulse as a heating source and the thermal lens decay is monitored by means of a CW He-Ne laser. The technique is fast and contactless and avoids some of the major difficulties of conventional methods. Thermal diffusivities for water and a polycarbonate plastic were measured and found to be in agreement with literature values. Considerable simplification and minimization of certain errors was achieved by use of a reference material.

  5. Analysis of Adaptive Fuzzy Technique for Multiple Crack Diagnosis of Faulty Beam Using Vibration Signatures

    Directory of Open Access Journals (Sweden)

    Amiya Kumar Dash

    2013-01-01

    Full Text Available This paper discusses the multicrack detection of structure using fuzzy Gaussian technique. The vibration parameters derived from the numerical methods of the cracked cantilever beam are used to set several fuzzy rules for designing the fuzzy controller used to predict the crack location and depth. Relative crack locations and relative crack depths are the output parameters from the fuzzy inference system. The method proposed in the current analysis is used to evaluate the dynamic response of cracked cantilever beam. The results of the proposed method are in good agreement with the results obtained from the developed experimental setup.

  6. A novel technique for tuning of co-axial cavity of multi-beam klystron

    Science.gov (United States)

    Saha, Sukalyan; Bandyopadhyay, Ayan Kumar; Pal, Debashis; Kant, Deepender; Joshi, Lalit Mohan; Kumar, Bijendra; Meena, Rakesh; Rawat, Vikram

    2016-03-01

    Multi-beam Klystrons (MBKs) have gained wide acceptances in the research sector for its inherent advantages. But developing a robust tuning technique for an MBK cavity of coaxial type has still remained a challenge as these designs are very prone to suffer from asymmetric field distribution with inductive tuning of the cavity. Such asymmetry leads to inhomogeneous beam-wave interaction, an undesirable phenomenon. Described herein is a new type of coaxial cavity that has the ability to suppress the asymmetry, thereby allowing tuning of the cavity with a single tuning post.

  7. Statistical signal processing techniques for coherent transversal beam dynamics in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Alhumaidi, Mouhammad

    2015-03-04

    identifying and analyzing the betatron oscillation sourced from the kick based on its mixing and temporal patterns. The accelerator magnets can generate unwanted spurious linear and non-linear fields due to fabrication errors or aging. These error fields in the magnets can excite undesired resonances leading together with the space charge tune spread to long term beam losses and reducing dynamic aperture. Therefore, the knowledge of the linear and non-linear magnets errors in circular accelerator optics is very crucial for controlling and compensating resonances and their consequent beam losses and beam quality deterioration. This is indispensable, especially for high beam intensity machines. Fortunately, the relationship between the beam offset oscillation signals recorded at the BPMs is a manifestation of the accelerator optics, and can therefore be exploited in the determination of the optics linear and non-linear components. Thus, beam transversal oscillations can be excited deliberately for purposes of diagnostics operation of particle accelerators. In this thesis, we propose a novel method for detecting and estimating the optics lattice non-linear components located in-between the locations of two BPMs by analyzing the beam offset oscillation signals of a BPMs-triple containing these two BPMs. Depending on the non-linear components in-between the locations of the BPMs-triple, the relationship between the beam offsets follows a multivariate polynomial accordingly. After calculating the covariance matrix of the polynomial terms, the Generalized Total Least Squares method is used to find the model parameters, and thus the non-linear components. A bootstrap technique is used to detect the existing polynomial model orders by means of multiple hypothesis testing, and determine confidence intervals for the model parameters.

  8. Room-Temperature Growth of SiC Thin Films by Dual-Ion-Beam Sputtering Deposition

    Directory of Open Access Journals (Sweden)

    C. G. Jin

    2008-01-01

    Full Text Available Silicon carbide (SiC films were prepared by single and dual-ion-beamsputtering deposition at room temperature. An assisted Ar+ ion beam (ion energy Ei = 150 eV was directed to bombard the substrate surface to be helpful for forming SiC films. The microstructure and optical properties of nonirradicated and assisted ion-beam irradicated films have been characterized by transmission electron microscopy (TEM, scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FTIR, and Raman spectra. TEM result shows that the films are amorphous. The films exposed to a low-energy assisted ion-beam irradicated during sputtering from a-SiC target have exhibited smoother and compacter surface topography than which deposited with nonirradicated. The ion-beam irradicated improves the adhesion between film and substrate and releases the stress between film and substrate. With assisted ion-beam irradicated, the density of the Si–C bond in the film has increased. At the same time, the excess C atoms or the size of the sp2 bonded clusters reduces, and the a-Si phase decreases. These results indicate that the composition of the film is mainly Si–C bond.

  9. Ion beam-assisted deposition of boron nitride from a condensed layer of diborane and ammonia at 78 K

    International Nuclear Information System (INIS)

    This paper examines the ion beam-assisted deposition (IBAD) of thin boron nitride films using cryogenically condensed precursors. Low energy (1100 eV) argon ad (2000 eV) deuterated ammonia beams with currents of 600--850 nA were used to mix and initiate reactions in frozen (90 K) layers of diborane (B2H6 and ammonia (NH3) or only B2H6, respectively. The resulting film is shown to be an amorphous BN coating approximately 30 Angstrom thick

  10. The Post—deposition Anneal Effects on the Electrical Properties of HfO2 Gate Dielectric Deposited by Ion Beam Sputtering at Room Temperature

    Institute of Scientific and Technical Information of China (English)

    KANGJinfeng; LIUXiaoyan; TIANDayu; WANGWei; LIANGuijun; XIONGGuangcheng; HANRuqi

    2003-01-01

    HfO2 high K gate dielectric films were fab-ricated on p-Si(100) substrates by ion beam sputtering at room temperature followed by a post-deposition anneal-ing (PDA). The PDA effects on the electrical properties of HfO2 gate dielectric films were studied. High quality HfO2 gate dielectric with small equivalent oxide thickness (EOT = 2.3nm), small hystereis (△VFB<50mV), and lowleakage current (< 1× 10-4A/cm2@lV) was fabricated.The studies of PDA effects on the electrical properties in-dicate that the PDA process in nitrogen ambient will be necessary for the HfO2 gate dielectric films deposited by ion beam sputtering the sintered target at room temper-ature in order to obtain small equivalent oxide thickness and low leakage currents, whereas a PDA in oxygen ambi-ent will be not required. The results also means that there is less oxygen vacancy defect produced in the HfO2 gate dielectric films during the deposition at room temperature.

  11. Electrical performance of phase change memory cells with Ge{sub 3}Sb{sub 2}Te{sub 6} deposited by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Boschker, Jos E.; Riechert, Henning; Calarco, Raffaella [Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany); Boniardi, Mattia; Redaelli, Andrea [Micron Semiconductor Italia S.r.l., Via C. Olivetti, 2, 20864, Agrate Brianza, MB (Italy)

    2015-01-12

    Here, we report on the electrical characterization of phase change memory cells containing a Ge{sub 3}Sb{sub 2}Te{sub 6} (GST) alloy grown in its crystalline form by Molecular Beam Epitaxy (MBE). It is found that the high temperature growth on the amorphous substrate results in a polycrystalline film exhibiting a rough surface with a grain size of approximately 80–150 nm. A detailed electrical characterization has been performed, including I-V characteristic curves, programming curves, set operation performance, crystallization activation at low temperature, and resistance drift, in order to determine the material related parameters. The results indicate very good alignment of the electrical parameters with the current state-of-the-art GST, deposited by physical vapor deposition. Such alignment enables a possible employment of the MBE deposition technique for chalcogenide materials in the phase change memory technology, thus leading to future studies of as-deposited crystalline chalcogenides as integrated in electrical vehicles.

  12. Reel-to-reel preparation of ion-beam assisted deposition (IBAD)-MgO based coated conductors

    International Nuclear Information System (INIS)

    We report on our efforts in developing and scaling-up the systems for IBAD-MgO based coated conductor fabrication. The overall fabrication process involves a number of different processes including: electropolishing of the substrates; barrier-layer, seed-layer, and IBAD-MgO deposition by e-beam evaporation; and pulsed laser deposition of buffer and YBCO layers. All processes are realized in reel-to-reel processing systems. Latest results have shown that the IBAD-MgO approach yields coated conductor performance comparable to the best results achieved elsewhere to date

  13. Reel-to-reel preparation of ion-beam assisted deposition (IBAD)-MgO based coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Kreiskott, Sascha; Arendt, Paul N; Coulter, J Yates; Dowden, Paul C; Foltyn, Stephen R; Gibbons, Brady J; Matias, Vladimir; Sheehan, Chris J [Superconductivity Technology Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2004-05-01

    We report on our efforts in developing and scaling-up the systems for IBAD-MgO based coated conductor fabrication. The overall fabrication process involves a number of different processes including: electropolishing of the substrates; barrier-layer, seed-layer, and IBAD-MgO deposition by e-beam evaporation; and pulsed laser deposition of buffer and YBCO layers. All processes are realized in reel-to-reel processing systems. Latest results have shown that the IBAD-MgO approach yields coated conductor performance comparable to the best results achieved elsewhere to date.

  14. Effects of oxygen on electron beam induced deposition of SiO2 using physisorbed and chemisorbed tetraethoxysilane

    Science.gov (United States)

    Bishop, James; Toth, Milos; Phillips, Matthew; Lobo, Charlene

    2012-11-01

    Electron beam induced deposition (EBID) is limited by low throughput and purity of as-grown material. Co-injection of O2 with the growth precursor is known to increase both the purity and deposition rate of materials such as SiO2 at room temperature. Here, we show that O2 inhibits rather than enhances EBID from tetraethoxysilane (TEOS) precursor at elevated temperatures. This behavior is attributed to surface site competition between chemisorbates at elevated temperature, and TEOS decomposition by atomic oxygen produced through electron dissociation of physisorbed O2 at room temperature.

  15. Effects of oxygen on electron beam induced deposition of SiO{sub 2} using physisorbed and chemisorbed tetraethoxysilane

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, James; Toth, Milos; Phillips, Matthew; Lobo, Charlene [School of Physics and Advanced Materials, University of Technology, Sydney, P.O. Box 123, Broadway, New South Wales 2007 (Australia)

    2012-11-19

    Electron beam induced deposition (EBID) is limited by low throughput and purity of as-grown material. Co-injection of O{sub 2} with the growth precursor is known to increase both the purity and deposition rate of materials such as SiO{sub 2} at room temperature. Here, we show that O{sub 2} inhibits rather than enhances EBID from tetraethoxysilane (TEOS) precursor at elevated temperatures. This behavior is attributed to surface site competition between chemisorbates at elevated temperature, and TEOS decomposition by atomic oxygen produced through electron dissociation of physisorbed O{sub 2} at room temperature.

  16. Ion beam co-deposition of HTSC films on SrTiO3 and ITO/Si

    International Nuclear Information System (INIS)

    Superconducting YBa2Cu3O7-δ (YBCO) thin films were grown on Si with transparent, conducting Indium Tin Oxide (ITO) buffer layers. The onset temperature at 92K and zero resistance at 68K were measured. Both, ITO and YBCO films were deposited by ion beam co-deposition. The YBCO/ITO films exhibit metallic resistivity with positive slopes (∼0.055 Ω/K). The YBCO is uniform, textured and polycrystalline. In this paper the relevance for hybrid opto-electronic device structures is briefly discussed

  17. Tilting of carbon encapsulated metallic nanocolumns in carbon-nickel nanocomposite films by ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Matthias [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Technische Universitaet Dresden, D-01062 Dresden (Germany); Muecklich, Arndt; Zschornak, Matthias; Wintz, Sebastian; Gemming, Sibylle; Abrasonis, Gintautas [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Oates, Thomas W. H. [Leibniz-Institut fuer Analytische Wissenschaft, ISAS e.V., Albert-Einstein-Str. 9, 12489 Berlin (Germany); Luis Endrino, Jose [Surfaces and Coatings Department, Instituto de Ciencia de Materiales de Madrid, c/Sor Juana Ines de la Cruz 3, Cantoblanco, 28049 Madrid (Spain); Baehtz, Carsten; Shalimov, Artem [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Rossendorf Beamline, European Synchrotron Radiation Facility, F-38043 Grenoble (France)

    2012-07-30

    The influence of assisting low-energy ({approx}50-100 eV) ion irradiation effects on the morphology of C:Ni ({approx}15 at. %) nanocomposite films during ion beam assisted deposition (IBAD) is investigated. It is shown that IBAD promotes the columnar growth of carbon encapsulated metallic nanoparticles. The momentum transfer from assisting ions results in tilting of the columns in relation to the growing film surface. Complex secondary structures are obtained, in which a significant part of the columns grows under local epitaxy via the junction of sequentially deposited thin film fractions. The influence of such anisotropic film morphology on the optical properties is highlighted.

  18. Synthesis of Colloidal ZnO Nanoparticles and Deposit of Thin Films by Spin Coating Technique

    Directory of Open Access Journals (Sweden)

    Jose Alberto Alvarado

    2013-01-01

    Full Text Available ZnO colloidal nanoparticles were synthesized, the average size of these nanoparticles is around 25 nm with hexagonal form. It was noted that stabilization depends directly on the purifying process; in this work we do not change the nature of the solution as a difference from Meulekamp's method, and we do not use any alkanes to remove the byproducts; only a centrifuge to remove those ones was used, thereby the stabilization increases up to 24 days. It is observed from the results that only three times of washing is enough to prevent the rapid aging process. The effect of annealing process on the composition, size, and geometrical shape of ZnO nanoparticles was studied in order to know whether the annealing process affects the crystallization and growth of the nanoparticles. After the synthesis, the colloidal nanoparticles were deposited by spin coating technique showing that the formed nanoparticles have no uniformly deposition pattern. But is possible to deposit those ones in glass substrates. A possible deposition process of the nanoparticles is proposed.

  19. Structural, optical and electrical properties of zinc oxide thin films deposited by a spray pyrolysis technique

    International Nuclear Information System (INIS)

    Zinc oxide (ZnO) thin films were deposited on glass substrates by spray pyrolysis technique decomposition of zinc acetate dihydrate in an ethanol solution with 30 mL of deposition rate, the ZnO thin films were deposited at two different temperatures: 300 and 350 °C. The substrates were heated using the solar cells method. The substrate was R217102 glass, whose size was 30 × 17.5 × 1 mm3. The films exhibit a hexagonal wurtzite structure with a strong (002) preferred orientation. The higher value of crystallite size is attained for sprayed films at 350 °C, which is probably due to an improvement of the crystallinity of the films at this point. The average transmittance of obtain films is about 90%–95%, as measured by a UV—vis analyzer. The band gap energy varies from 3.265 to 3.294 eV for the deposited ZnO thin film at 300 and 350 °C, respectively. The electrical resistivity measured of our films are in the order 0.36 Ω·cm. (semiconductor materials)

  20. Functional metal oxide coatings by molecule-based thermal and plasma chemical vapor deposition techniques.

    Science.gov (United States)

    Mathur, S; Ruegamer, T; Donia, N; Shen, H

    2008-05-01

    Deposition of thin films through vaccum processes plays an important role in industrial processing of decorative and functional coatings. Many metal oxides have been prepared as thin films using different techniques, however obtaining compositionally uniform phases with a control over grain size and distribution remains an enduring challenge. The difficulties are largely related to complex compositions of functional oxide materials, which makes a control over kinetics of nucleation and growth processes rather difficult to control thus resulting in non-uniform material and inhomogeneous grain size distribution. Application of tailor-made molecular precursors in low pressure or plasma-enhanced chemical vapor deposition (CVD) techniques offers a viable solution for overcoming thermodynamic impediments involved in thin film growth. In this paper molecule-based CVD of functional coatings is demonstrated for iron oxide (Fe2O3, Fe3O4), vanadium oxide (V2O5, VO2) and hafnium oxide (HfO2) phases followed by the characterization of their microstructural, compositional and functional properties which support the advantages of chemical design in simplifying deposition processes and optimizing functional behavior. PMID:18572690

  1. Radiation detectors based on Multiwall Carbon Nanotubes deposited by a spray technique

    Energy Technology Data Exchange (ETDEWEB)

    Melisi, D., E-mail: domenico.melisi@ba.infn.it [INFN – Sezione di Bari, Via Orabona 4, 70126 (Italy); Nitti, M.A. [Department of Physics, University of Bari “A. Moro”, Via Orabona 4, 70126 (Italy); Valentini, M. [INFN – Sezione di Bari, Via Orabona 4, 70126 (Italy); Valentini, A. [INFN – Sezione di Bari, Via Orabona 4, 70126 (Italy); Department of Physics, University of Bari “A. Moro”, Via Orabona 4, 70126 (Italy); Ditaranto, N.; Cioffi, N. [Department of Chemistry, University of Bari “A. Moro”, Via Orabona 4, 70126 (Italy); Di Franco, C. [CNR-IFN Bari, Via Amendola 173, 70126 (Italy)

    2013-09-30

    In this paper a study of Multi Wall Carbon Nanotube films deposited at low temperature by means of a spray technique on different substrates is presented. Nanodispersion of nanotube powder in a non-polar 1,2-dichloroethane solvent was used as starting solution. Electron Microscopy in Scanning and Transmission modes were used in order to verify the morphological properties of the deposited films. Visible light detectors were prepared spraying Multi Wall Carbon Nanotubes on silicon substrates with different layouts. In some detectors the nanotubes were covered by an Indium Tin Oxide (ITO) layer. Electrical measurements, both in dark and under light irradiation, were performed and Current-Voltage characteristics are reported. The Indium Tin Oxide coating effect on the photoconductivity yield is presented and discussed along with device ageing test, resulting in a very good photoconduction and stability over four months. - Highlights: • Carbon nanotubes were deposited at low temperature using a spray technique. • Visible photodetectors based on carbon nanotubes films were produced. • Contribution of carbon nanotubes to the quantum efficiency is shown. • Charge collection from the devices increases with an indium tin oxide contact. • Time stability of photodetectors based on carbon nanotubes is demonstrated.

  2. Liquid phase deposition methods monitoring techniques influence for solid substrates and thin metal oxide films properties

    Directory of Open Access Journals (Sweden)

    A.V. Valiulis

    2007-09-01

    Full Text Available Purpose: Liquid phase deposition (LPD method is a useful method to create thin oxide films from aqueous solutions under ambient conditions. Deposition of ceramic layers on polymers is a technological challenge because of polymer sensitivity to chemicals and high temperature processing.Design/methodology/approach: The work attempts to elucidate the role of the substrate during LPD of TiO2 films by using Kapton with different types of surface treatments.Findings: Was found that small differences in pH, temperature, and solution composition can lead to dramatic differences in the film’s crystallinity, adherence, and growth rate. Thin films are very smooth, uniform with small amount of cracks.Research limitations/implications: Independent of technique and substrate, film thicker than a few hundred nm exhibited cracks, attributed to stresses that result during drying of the film.Originality/value: Techniques for monitoring the surface chemistry of the solid substrate and the deposited ceramic film have been developed.

  3. Application of the combined electrochemical quartz crystal microbalance and probe beam deflection technique in deep eutectic solvents

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • The EQCM/PBD method has for the first time been applied to metal deposition/dissolution processes in deep eutectic solvents • The PBD responds to solution phase chemistry, while the E and QCM probes respond to interfacial processes only • The combination of electrochemical (E), gravimetric (QCM) and optical (PBD) responses provides diagnostic capability • EQCM/PBD data reveal the influence of Ag/Cl− complex speciation in the high chloride concentration ionic liquid • The PBD response reveals the intrusion of solubility limitations into Sn anodic stripping - Abstract: The electrochemical quartz crystal microbalance (EQCM) and probe beam deflection (PBD) have been widely used to study interfacial processes in molecular solvent-based electrolytes. However, there has been limited use of the EQCM and none of PBD in room temperature ionic liquids, including deep eutectic solvents (DES). Here we explore the use of the combined EQCM/PBD technique to the study of Ag and Sn electrodeposition from a DES comprising a 1:2 mixture of choline chloride and ethylene glycol. While overcoming the effect of viscous loss in the acoustic wave (EQCM) part of the experiment is understood, the optical (PBD) technique fails to provide a meaningful response in slow scan rate voltammetric experiments; this contrasts sharply with the straightforward behaviour seen in aqueous media. Solution transport considerations reveal this to be a consequence of long surface-to-beam transit times in the viscous DES. The problem can be overcome by operating at scan rates 1-2 orders of magnitude slower, permitting application of this powerful technique to novel media of technological interest. The PBD responses reveal unanticipated chemical effects: multiple complexes in the Ag system and solubility limitations in the Sn system, neither of which is evident from the electrochemical or QCM responses

  4. Adhesion-enhanced thick copper film deposition on aluminum oxide by an ion-beam-mixed Al seed layer

    International Nuclear Information System (INIS)

    We report a highly-adherent 30-μm Cu conductive-path coating on an aluminum-oxide layer anodized on an aluminum-alloy substrate for a metal-printed circuit-board application. A 50-nm Al layer was first coated with an e-beam evaporative deposition method on the anodized oxide, followed by ion bombardment to mix the interfacial region. Subsequently, a Cu coating was deposited onto the mixed seed layer to the designed thickness. Adhesions of the interface were tested by using tape adhesion test, and pull-off tests and showed commercially acceptable adhesions for such thick coating layers. The ion beam mixing (IBM) plays the role of fastening the thin seed coating layer to the substrate and enhancing the adhesion of the Cu conductive path on the anodized aluminum surface.

  5. Minimal interference beam size/profile measurement techniques applicable to the Collider

    International Nuclear Information System (INIS)

    The imaging of synchrotron radiation (SR) has been suggested as a technique for providing a continuous, non-interfering monitor of the beam profile in the Collider rings at the Superconducting Super Collider. A closer examination has raised questions concerning the applicability of SR imaging in this case because of the diffraction broadening of the image, the requirements for axial space and location in the lattice, and the complexity of the system. We have surveyed the known, alternative, minimal interference techniques for measuring beam size and have evaluated them for possible Collider usage. We conclude that of the approaches that appear feasible, all require at least some development for our usage and that the development of an electron beam probe offers the best promise. We recommend that flying wires be used for cross-checking and calibrating the electron beam probe diagnostic and for luminosity measurements when the highest accuracy is required, but flying wires should not be used as the primary diagnostic because of their limited lifetime

  6. Minimal interference beam size/profile measurement techniques applicable to the Collider

    Energy Technology Data Exchange (ETDEWEB)

    Nexsen, W.; Dutt, S.; Kauffmann, S.; Lebedev, V.; Maschke, A.; Mokhov, N.; Richardson, R.; Tsyganov, E.; Zinchenko, A.

    1993-05-01

    The imaging of synchrotron radiation (SR) has been suggested as a technique for providing a continuous, non-interfering monitor of the beam profile in the Collider rings at the Superconducting Super Collider. A closer examination has raised questions concerning the applicability of SR imaging in this case because of the diffraction broadening of the image, the requirements for axial space and location in the lattice, and the complexity of the system. We have surveyed the known, alternative, minimal interference techniques for measuring beam size and have evaluated them for possible Collider usage. We conclude that of the approaches that appear feasible, all require at least some development for our usage and that the development of an electron beam probe offers the best promise. We recommend that flying wires be used for cross-checking and calibrating the electron beam probe diagnostic and for luminosity measurements when the highest accuracy is required, but flying wires should not be used as the primary diagnostic because of their limited lifetime.

  7. New technique for investigation of solar cell sheet resistance distribution by laser beam scanning

    Science.gov (United States)

    Goncharov, Vadym O.; Ilchenko, Leonid M.; Kilchitskaya, S.; Litvinenko, Sergiy V.; Smirnov, Eugene M.

    1998-04-01

    Laser beam scanning was applied for evaluating the distribution of sheet resistance of solar cell emitter. It was shown that the voltage drop around the illuminated spot has an information about the local sheet resistance since the most part of the voltage drop occurs near the illuminated area. The current under local illumination in reverse direction depends on the local quantum efficiency while in forward direction it depends on the same local properties and on the local sheet resistance. The processing of laser beam induced current images at different bias voltage gives a map of local sheet resistance complementing other techniques for investigation the electron devices. We investigated one and dual-beam technique for amplitude and phase LBIC measurement by means of universal laser scanning microscope worked in amplitude and differential-phase regimes. Acousto-optical scanning results in 2D distribution of amplitude or phase LBIC. For convenience of image processing and visualization, TV type scanning is applied to laser beams.

  8. Modulating the Optoelectronic Properties of Silver Nanowires Films: Effect of Capping Agent and Deposition Technique

    Directory of Open Access Journals (Sweden)

    D. Lopez-Diaz

    2015-11-01

    Full Text Available Silver nanowires 90 nm in diameter and 9 µm in length have been synthesized using different capping agents: polyvinyl pyrrolidone (PVP and alkyl thiol of different chain lengths. The nanowire structure is not influenced by the displacement of PVP by alkyl thiols, although alkyl thiols modify the lateral aggregation of nanowires. We examined the effect of the capping agent and the deposition method on the optical and electrical properties of films prepared by Spray and the Langmuir-Schaefer methodologies. Our results revealed that nanowires capped with PVP and C8-thiol present the best optoelectronic properties. By using different deposition techniques and by modifying the nanowire surface density, we can modulate the optoelectronic properties of films. This strategy allows obtaining films with the optoelectronic properties required to manufacture touch screens and electromagnetic shielding.

  9. Studies of aluminum oxide thin films deposited by laser ablation technique

    Science.gov (United States)

    Płóciennik, P.; Guichaoua, D.; Korcala, A.; Zawadzka, A.

    2016-06-01

    This paper presents the structural and optical investigations of the aluminum oxide nanocrystalline thin films. Investigated films were fabricated by laser ablation technique in high vacuum onto quartz substrates. The films were deposited at two different temperatures of the substrates equal to room temperature and 900 K. X-ray Diffraction spectra proved nanocrystalline character and the corundum phase of the film regardless on the substrate temperature during the deposition process. Values of the refractive indices, extinction and absorption coefficients were calculated by using Transmission and Reflection Spectroscopy in the UV-VIS-NIR range of the wavelength. Coupling Prism Method was used for films thickness estimations. Experimental measurements and theoretical calculations of the Third Harmonic Generation were also reported. Obtained results show that the lattice strain may affect obtained values of the third order nonlinear optical susceptibility.

  10. Fabricating Arrays of Vanadium Dioxide Nanodisks by Focused Ion-Beam Lithography and Pulsed-Laser Deposition

    International Nuclear Information System (INIS)

    Vanadium dioxide undergoes a structural (monoclinic to tetragonal) insulator-to-metal transition at 70 C, accompanied by large changes in electrical and optical properties. By combining focused ion-beam lithography and pulsed laser depo-sition, patterned arrays of vanadium dioxide nanoparticles are created that can be used for studies of linear and nonlinear optical physics, as well as demonstrating the potential for a variety of applications.

  11. Crystalline garnet Bragg reflectors for high power, high temperature, and integrated applications fabricated by multi-beam pulsed laser deposition

    OpenAIRE

    Sloyan, Katherine A.; May-Smith, Timothy C.; Zervas, Michalis N.; Eason, Robert W.

    2012-01-01

    Crystalline Bragg reflectors are of interest for high power, high temperature and integrated applications. We demonstrate the automated growth of such structures by shuttered multi-beam Pulsed Laser Deposition (PLD). Geometries include 145 layer stacks exhibiting >99.5% reflection and ? phase-shifted designs. A crystalline grating strength-apodized sample was grown by mixing plumes to obtain layers with custom refractive indices. Peak reflection wavelength was tuneable with incident position,...

  12. Silver nano-particles in fluoride films fabricated by Pulsed Laser Deposition with auxiliary Electron Beam Evaporation

    Czech Academy of Sciences Publication Activity Database

    Novotný, Michal; Lančok, Ján; Bulíř, Jiří; Hruška, Petr; Fekete, Ladislav; Fitl, Přemysl

    Strasbourg: European Materials Research Society, 2013. [E- MRS 2013 Spring Meeting. 27.05.2013-31.05.2013, Strasbourg] R&D Projects: GA MŠk(CZ) 7AMB12FR034; GA ČR(CZ) GAP108/11/1312 Grant ostatní: AVČR(CZ) M100101271 Institutional support: RVO:68378271 Keywords : lanthanum fluoride * calcium fluoride * thin film * silver nanoparticles * pulsed laser deposition * electron beam evaporation Subject RIV: BM - Solid Matter Physics ; Magnetism

  13. Comparison of Morphology Evolution of Ge(001) Homoepitaxial Films Grown by Pulsed Laser Deposition and Molecular Beam Epitaxy

    OpenAIRE

    McCamy, James W.; Shin, Byungha; Leonard, John P.; Aziz, Michael

    2005-01-01

    Using a dual Molecular Beam Epitaxy (MBE)-Pulsed Laser Deposition (PLD) Ultra-High Vacuum chamber, we have conducted the first experiments under identical thermal, background, and surface preparation conditions to compare Ge(001) homoepitaxial growth morphology in PLD and MBE. We find that in PLD with low kinetic energy and in MBE the film morphology evolves in a similar fashion: initially irregularly shaped mounds form, followed by pyramidal mounds with edges of the square-base along direc...

  14. Cavity Ringdown Technique for negative-hydrogen-ion measurement in ion source for neutral beam injector

    International Nuclear Information System (INIS)

    The Cavity Ringdown Technique (CRD) is applied for negative hydrogen ion (H−) density measurement in H− source for the neutral beam injector. The CRD is one of the laser absorption techniques. Nd:YAG pulse laser was utilized for negative-hydrogen-ion photodetachment. The H− density related to extracted H− beam was successfully observed by a fixed position CRD. A two-dimensional movable CRD has been developed to measure the H− density profile. Measured profiles were consistent with expected profiles from the H− production area in pure hydrogen and cesium seeded plasmas. By applying absorption saturation in the optical cavity, negative hydrogen ion temperature was evaluated and was confirmed as being a similar value measured with other diagnostics

  15. Transverse Phase Space Reconstruction and Emittance Measurement of Intense Electron Beams using a Tomography Technique

    International Nuclear Information System (INIS)

    Tomography is the technique of reconstructing an image from its projections. It is widely used in the medical community to observe the interior of the human body by processing multiple x-ray images taken at different angles, A few pioneering researchers have adapted tomography to reconstruct detailed phase space maps of charged particle beams. Some questions arise regarding the limitations of tomography technique for space charge dominated beams. For instance is the linear space charge force a valid approximation? Does tomography equally reproduce phase space for complex, experimentally observed, initial particle distributions? Does tomography make any assumptions about the initial distribution? This study explores the use of accurate modeling with the particle-in-cell code WARP to address these questions, using a wide range of different initial distributions in the code. The study also includes a number of experimental results on tomographic phase space mapping performed on University of Maryland Electron Ring (UMER)

  16. A Review: Welding Of Dissimilar Metal Alloys by Laser Beam Welding & Friction Stir Welding Techniques

    Directory of Open Access Journals (Sweden)

    Ms. Deepika Harwani

    2014-12-01

    Full Text Available Welding of dissimilar metals has attracted attention of the researchers worldwide, owing to its many advantages and challenges. There is no denial in the fact that dissimilar welded joints offer more flexibility in the design and production of the commercial and industrial components. Many welding techniques have been analyzed to join dissimilar metal combinations. The objective of this paper is to review two such techniques – Laser welding and Friction stir welding. Laser beam welding, a high power density and low energy-input process, employs a laser beam to produce welds of dissimilar materials. Friction stir welding, a solid-state joining process, is also successfully used in dissimilar welding applications like aerospace and ship building industries. This paper summarizes the trends and advances of these two welding processes in the field of dissimilar welding. Future aspects of the study are also discussed.

  17. Phased-array beam steering using optical true time delay technique

    Science.gov (United States)

    Yang, Dong-Hua; Lin, Wen-Piao

    2015-09-01

    An optical dispersion technique for phased-array beam steering is proposed and analyzed. Optical true time delay using a high-dispersion compensation fiber (HDCF) and a phased array antenna (PAA) can provide a continuous radio-frequency squint-free beam scanning. When the dispersion of the fabricated DCF-C band is as high as -1020±31 ps/nm/km, the laser wavelength can be tuned from 1549.95 to 1550.2 nm. The experimental results confirmed that the scanning angle of far field radiation patterns for proposed technique can be tuned to have a range 51° (from -22° to +29°) at frequency of 5.9, 12.7 and 17 GHz.

  18. Determination of Redistribution of Erosion/Deposition Rate in Cultivated Area Using 137Cs Technique

    International Nuclear Information System (INIS)

    The aim of the research is to determine the rate of redistribution of erosion/deposition in cultivated area. The application of 137Cs technique was carried out at cultivated area in Bojong - Ciawi, with slope less than 10o and slope length of about 2 km. A reference site was selected at the top of the slope, and this site is flat, open and covered with grass. Two sites in the cultivated area were selected as study site namely LU-I ( 15 x 25 ) m with the distance of 1000 m from the top, and LU-II (17.5 x 20) m with the distance of 1300 m from the top. Sampling of soil at reference site was done by using scraper (20 x 50) cm, while sampling at study site by using core sampling (di = 7 cm). Soil samples were brought to the laboratorium for preparation and analysis of 137Cs content. Preparation are including of drying, weighing the total dry, sieving and crushing. Analysis of 137Cs content was done using multi channel analyzer (MCA) that connected to high purity germanium (HPGe), at 661 keV, and the minimum counting time of 16 hours. To estimate the erosion/deposit rate, two mathematical model were used, namely Proportional Model (PM) and Mass Balance Model 1 (MBM1). The result for application of 137Cs technique showed that MBM1 gives somewhat higher value for deposit rate and somewhat lower value for erosion than PM. Land use - I (LU-I) of Bojong - Ciawi was suffering from erosion with the erosion rate from 1 t/(ha.y) to 13 t/(ha.y), and LU-II has deposit rate from 1 t/(ha.y) to 50 t/(ha.y). (author)

  19. Synthesis of conductive semi-transparent silver films deposited by a Pneumatically-Assisted Ultrasonic Spray Pyrolysis Technique

    International Nuclear Information System (INIS)

    Highlights: • We deposited metallic silver films without post-deposition annealing. • The spray pyrolysis technique is of low cost and scalable for industrial applications. • We obtained deposition rate of 60 nm min−1 at 300 °C. • The average resistivity was 1E−7 Ω m. • Semi-transparent silver films were obtained at 350 °C and deposition time of 45 s. -- Abstract: The synthesis and characterization of nanostructured silver films deposited on corning glass by a deposition technique called Pneumatically-Assisted Ultrasonic Spray Pyrolysis are reported. Silver nitrate and triethanolamine were used as silver precursor and reducer agent, respectively. The substrate temperatures during deposition were in the range of 300–450 °C and the deposition times from 30 to 240 s. The deposited films are polycrystalline with cubic face-centered structure, and crystalline grain size less than 30 nm. Deposition rates up to 600 Å min−1 were obtained at substrate temperature as low as 300 °C. The electrical, optical, and morphological properties of these films are also reported. Semi-transparent conductive silver films were obtained at 350 °C with a deposition time of 45 s

  20. Synthesis of conductive semi-transparent silver films deposited by a Pneumatically-Assisted Ultrasonic Spray Pyrolysis Technique

    Energy Technology Data Exchange (ETDEWEB)

    Zaleta-Alejandre, E.; Balderas-Xicoténcatl, R. [Centro de Investigación y de Estudios Avanzados-IPN, Departamento de Física, , Apdo. Postal 14-470, Del, Gustavo A. Madero, C.P. 07000, México, D.F. (Mexico); Arrieta, M.L. Pérez [Universidad Autónoma de Zacatecas, Unidad Académica de Física, Calzada Solidaridad esq. Paseo, La Bufa s/n, C.P. 98060, Zacatecas, México (Mexico); Meza-Rocha, A.N.; Rivera-Álvarez, Z. [Centro de Investigación y de Estudios Avanzados-IPN, Departamento de Física, , Apdo. Postal 14-470, Del, Gustavo A. Madero, C.P. 07000, México, D.F. (Mexico); Falcony, C., E-mail: cfalcony@fis.cinvestav.mx [Centro de Investigación y de Estudios Avanzados-IPN, Departamento de Física, , Apdo. Postal 14-470, Del, Gustavo A. Madero, C.P. 07000, México, D.F. (Mexico)

    2013-10-01

    Highlights: • We deposited metallic silver films without post-deposition annealing. • The spray pyrolysis technique is of low cost and scalable for industrial applications. • We obtained deposition rate of 60 nm min{sup −1} at 300 °C. • The average resistivity was 1E−7 Ω m. • Semi-transparent silver films were obtained at 350 °C and deposition time of 45 s. -- Abstract: The synthesis and characterization of nanostructured silver films deposited on corning glass by a deposition technique called Pneumatically-Assisted Ultrasonic Spray Pyrolysis are reported. Silver nitrate and triethanolamine were used as silver precursor and reducer agent, respectively. The substrate temperatures during deposition were in the range of 300–450 °C and the deposition times from 30 to 240 s. The deposited films are polycrystalline with cubic face-centered structure, and crystalline grain size less than 30 nm. Deposition rates up to 600 Å min{sup −1} were obtained at substrate temperature as low as 300 °C. The electrical, optical, and morphological properties of these films are also reported. Semi-transparent conductive silver films were obtained at 350 °C with a deposition time of 45 s.

  1. Comparative analysis of electrophysical properties of ceramic tantalum pentoxide coatings, deposited by electron beam evaporation and magnetron sputtering methods

    Science.gov (United States)

    Donkov, N.; Mateev, E.; Safonov, V.; Zykova, A.; Yakovin, S.; Kolesnikov, D.; Sudzhanskaya, I.; Goncharov, I.; Georgieva, V.

    2014-12-01

    Ta2O5 ceramic coatings have been deposited on glass substrates by e-beam evaporation and magnetron sputtering methods. For the magnetron sputtering process Ta target was used. X-ray diffraction measurements show that these coatings are amorphous. XPS survey spectra of the ceramic Ta2O5 coatings were obtained. All spectra consist of well-defined XPS lines of Ta 4f, 4d, 4p and 4s; O 1s; C 1s. Ta 4f doublets are typical for Ta2O5 coatings with two main peaks. Scanning electron microscopy and atomic force microscopy images of the e-beam evaporated and magnetron sputtered Ta2O5 ceramic coatings have revealed a relatively flat surface with no cracks. The dielectric properties of the tantalum pentoxide coatings have been investigated in the frequency range of 100 Hz to 1 MHz. The electrical behaviour of e-beam evaporated and magnetron sputtered Ta2O5 ceramic coatings have also been compared. The deposition process conditions principally effect the structure parameters and electrical properties of Ta2O5 ceramic coatings. The coatings deposited by different methods demonstrate the range of dielectric parameters due to the structural and stoichiometric composition changes

  2. Mechanical properties and wear resistance of ion-beam-assisted sputter-deposited NiTi(N) coatings

    International Nuclear Information System (INIS)

    Thin films are deposited on an austenitic type 304L stainless steel using the sputtering of an Ni49Ti51 target with 1.5 keV N+ ions. The influence of a simultaneous 160 keV Ar+ implantation on hardness and wear resistance is studied. Hardness is measured with a nanoindenter. N+ reactive sputtering forms a coating harder than the substrate. The hardness increases by 80% when the eposit is ion beam assisted. Transmission electron microscopy analyses of the thin films reveal that the N+ sputtered films present a large content of nitrogen which forms with titanium strong disorganized metal-metalloid Ti-N bonds; when ion implantation is simultaneously used, very tiny crystalline TiN precipitates embedded in an amorphous matrix are observed. This could explain the increase in hardness. The simultaneous ion irradiation would favour TiN precipitation through an enhanced diffusion mechanism in the cascades. Subsequent wear resistance of these coatings is measured through three-dimensional profile analyses of the wear tracks obtained after tests performed on a pin-on-disc machine. It is shown that sputtered NiTi(N) coatings largely increase the wear resistance. When the deposit is ion beam assisted, the improvement is much more pronounced; it can be related to either the increase in the hardness or the ion beam mixing of the interface, or both these processes. The influence of the coating thickness and the ratio of the implanted ions to the deposited atoms are also studied. (orig.)

  3. Nanocomposite metal amorphous-carbon thin films deposited by hybrid PVD and PECVD technique.

    Science.gov (United States)

    Teixeira, V; Soares, P; Martins, A J; Carneiro, J; Cerqueira, F

    2009-07-01

    Carbon based films can combine the properties of solid lubricating graphite structure and hard diamond crystal structure, i.e., high hardness, chemical inertness, high thermal conductivity and optical transparency without the crystalline structure of diamond. Issues of fundamental importance associated with nanocarbon coatings are reducing stress, improving adhesion and compatibility with substrates. In this work new nanocomposite coatings with improved toughness based in nanocrystalline phases of metals and ceramics embedded in amorphous carbon matrix are being developed within the frame of a research project: nc-MeNxCy/a-C(Me) with Me = Mo, Si, Al, Ti, etc. Carbide forming metal/carbon (Me/C) composite films with Me = Mo, W or Ti possess appropriate properties to overcome the limitation of pure DLC films. These novel coating architectures will be adopted with the objective to decrease residual stress, improve adherence and fracture toughness, obtain low friction coefficient and high wear-resistance. Nanocomposite DLC's films were deposited by hybrid technique using a PVD-Physically Vapor Deposition (magnetron sputtering) and Plasma Enhanced Chemical Vapor Deposition (PECVD), by the use of CH4 gas. The parameters varied were: deposition time, substrate temperature (180 degrees C) and dopant (Si + Mo) of the amorphous carbon matrix. All the depositions were made on silicon wafers and steel substrates precoated with a silicon inter-layer. The characterisation of the film's physico-mechanical properties will be presented in order to understand the influence of the deposition parameters and metal content used within the a-C matrix in the thin film properties. Film microstructure and film hybridization state was characterized by Raman Spectroscopy. In order to characterize morphology SEM and AFM will be used. Film composition was measured by Energy-Dispersive X-ray analysis (EDS) and by X-ray photoelectron spectroscopy (XPS). The contact angle for the produced DLC's on

  4. Studies of aerosol particle formation from various sources using ion and electron beam analytical techniques.

    OpenAIRE

    Gharibi, Arash

    2006-01-01

    The thesis presents the results of studies of aerosol particle formation using ion and electron beam analytical techniques. The sources of aerosol particle formation studied are the following: 1. production of primary aerosol particles in the high Arctic region during summers 2. emission of ultrafine aerosol particles from wear on the road-tire interface 3. emission of aerosol particles from district heating units operating on three commonly-used biofuels. A source...

  5. A Technique for Temperature and Ultimate Load Calculations of Thin Targets in a Pulsed Electron Beam

    DEFF Research Database (Denmark)

    Hansen, Jørgen-Walther; Lundsager, Per

    1979-01-01

    A technique is presented for the calculation of transient temperature distributions and ultimate load of rotationally symmetric thin membranes with uniform lateral load and exposed to a pulsed electron beam from a linear accelerator. Heat transfer by conduction is considered the only transfer...... mechanism. The ultimate load is calculated on the basis of large plastic strain analysis. Analysis of one aluminum and one titanium membrane is shown....

  6. A novel technique for the deposition of aluminium-doped zinc oxide films

    International Nuclear Information System (INIS)

    Aluminium-doped zinc oxide is used in many applications as a transparent conductive oxide coating. Such coatings are often deposited by DC reactive sputtering of metallic targets, or RF sputtering of ceramic targets. Both of these techniques have their limitations. In the DC case, alloy targets are expensive and only allow a single composition per target. Additionally, in the RF case, targets produced by hot-pressing, or sintering may have a tendency to crack unless sputtered at low powers, thus restricting the deposition rate. However, sputtering from blended powder targets offers a potential solution to all of these problems. In this project, therefore, a series of Al-doped ZnO films have been produced by the pulsed DC magnetron sputtering of blended ZnO/Al2O3 powder targets. Initial results, presented here, indicate that high quality, defect-free films can be produced with suitable electrical and optical properties. The crystallinity of the films has been examined by X-ray diffraction, before and after annealing in controlled atmospheres. A thorough investigation of glass substrate cleaning techniques has also been carried out, with the effectiveness of each technique being assessed in terms of the coating-to-substrate adhesion, as measured by the scratch testing method

  7. The Effect of Annealing on the Structural and Optical Properties of Titanium Dioxide Films Deposited by Electron Beam Assisted PVD

    Directory of Open Access Journals (Sweden)

    Yaser M. Abdulraheem

    2013-01-01

    Full Text Available Titanium dioxide thin films were deposited on crystalline silicon substrates by electron beam physical vapor deposition. The deposition was performed under vacuum ranging from 10−5 to 10−6 Torr without process gases, resulting in homogeneous TiO2-x layers with a thickness of around 100 nm. Samples were then annealed at high temperatures ranging from 500°C to 800°C for 4 hours under nitrogen, and their structural and optical properties along with their chemical structure were characterized before and after annealing. The chemical and structural characterization revealed a substoichiometric TiO2-x film with oxygen vacancies, voids, and an interface oxide layer. It was found from X-ray diffraction that the deposited films were amorphous and crystallization to anatase phase occurred for annealed samples and was more pronounced for annealing temperatures above 700°C. The refractive index obtained through spectroscopic ellipsometry ranged between 2.09 and 2.37 in the wavelength range, 900 nm to 400 nm for the as-deposited sample, and jumped to the range between 2.23 and 2.65 for samples annealed at 800°C. The minimum surface reflectance changed from around 0.6% for the as-deposited samples to 2.5% for the samples annealed at 800°C.

  8. Overview of Alternative Bunching and Current-shaping Techniques for Low-Energy Electron Beams

    Energy Technology Data Exchange (ETDEWEB)

    Piot, Philippe [Northern Illinois U.

    2015-12-01

    Techniques to bunch or shape an electron beam at low energies (E <15 MeV) have important implications toward the realization of table-top radiation sources [1] or to the design of compact multi-user free-electron lasers[2]. This paper provides an overview of alternative methods recently developed including techniques such as wakefield-based bunching, space-charge-driven microbunching via wave-breaking [3], ab-initio shaping of the electron-emission process [4], and phase space exchangers. Practical applications of some of these methods to foreseen free-electron-laser configurations are also briefly discussed [5].

  9. Accelerated single-beam wavefront reconstruction techniques based on relaxation and multiresolution strategies.

    Science.gov (United States)

    Falaggis, Konstantinos; Kozacki, Tomasz; Kujawinska, Malgorzata

    2013-05-15

    A previous Letter by Pedrini et al. [Opt. Lett. 30, 833 (2005)] proposed an iterative single-beam wavefront reconstruction algorithm that uses a sequence of interferograms recorded at different planes. In this Letter, the use of relaxation and multiresolution strategies is investigated in terms of accuracy and computational effort. It is shown that the convergence rate of the conventional iterative algorithm can be significantly improved with the use of relaxation techniques combined with a hierarchy of downsampled intensities that are used within a preconditioner. These techniques prove to be more robust, to achieve a higher accuracy, and to overcome the stagnation problem met in the iterative wavefront reconstruction. PMID:23938902

  10. Thickness and component distributions of yttrium-titanium alloy films in electron-beam physical vapor deposition

    Institute of Scientific and Technical Information of China (English)

    LI ShuaiHui; SHU YongHua; FAN Jing

    2008-01-01

    Thickness and component distributions of large-area thin films are an issue of in-ternational concern in the field of material processing. The present wor0k employs experiments and direct simulation Monte Carlo (DSMC) method to investigate three-dimensional low-density, non-equilibrium jets of yttrium and titanium vapor atoms in an electron-beams physical vapor deposition (EBPVD) system furnished with two or three electron-beams, and obtains their deposition thickness and component distributions onto 4-inch and 6-inch mono-crystal silicon wafers. The DSMC results are found in excellent agreement with our measurements, such as evaporation rates of yttrium and titanium measured in-situ by quartz crystal reso-nators, deposited film thickness distribution measured by Rutherford backscat-tering spectrometer (RBS) and surface profilometer and deposited film molar ratio distribution measured by RBS and inductively coupled plasma atomic emission spectrometer (ICP-AES). This can be taken as an indication that a combination of DSMC method with elaborate measurements may be satisfactory for predicting and designing accurately the transport process of EBPVD at the atomic level.

  11. Ion-beam assisted deposition of MgO with in situ RHEED monitoring to control Bi-axial texture

    Energy Technology Data Exchange (ETDEWEB)

    Arendt, P. N. (Paul N.); Foltyn, S. R. (Stephen R.); Jia, Quanxi; DePaula, R. F. (Raymond Felix); Dowden, P. C. (Paul C.); Kung, H. (Harriett); Holesinger, T. G. (Terry G.); Stan, L. (Liliana); Emmert, L. A. (Luke A.); Peterson, E. J. (Eric J.); Groves, J. R. (James R.)

    2001-01-01

    We have studied the growth of magnesium oxide using ion-beam assisted deposition (IBAD) to achieve (100) oriented, bi-axially textured films with low mosaic spread, for film thicknesses of 10 nm on silicon substrates. We have refined the process by using reflected high-energy electron diffraction (RHEED) to monitor the growth of IBAD MgO films and found that the diffracted intensity can be used to determine (and ultimately control) final in-plane texture of the film. Here we present results on our work to develop the use of real-time RHEED monitoring to deposit well-oriented IBAD MgO films. The results have been corroborated with extensive grazing-incidence X-ray diffraction (GID). Results of these analyses have allowed us to deposit films on metallic substrates with in-plane mosaic spread less than 7{sup o}.

  12. Molecular beam epitaxy deposition of Gd2O3 thin films on SrTiO3 (100) substrate

    Science.gov (United States)

    Wang, Jinxing; Hao, Jinghua; Zhang, Yangyang; Wei, Hongmei; Mu, Juyi

    2016-06-01

    Gd2O3 thin films are grown on the SrTiO3 (100) substrate by molecular beam epitaxy (MBE) deposition. X-ray diffraction (XRD) analysis, conventional transmission electron microscopy (TEM) and aberration-corrected scanning transmission electron microscopy (STEM) are performed to investigate the microstructure of deposited thin films. It is found that the as-deposited thin film possesses a very uniform thickness of ∼40 nm and is composed of single cubic phase Gd2O3 grains. STEM and TEM observations reveal that Gd2O3 thin film grows epitaxially on the SrTiO3 (100) substrate with (001)Gd2O3//(100)STO and [110]Gd2O3//[001]STO orientations. Furthermore, the Gd atoms are found to diffuse into the SrTiO3 substrate for a depth of one unit cell and substitute for the Sr atoms near the interface.

  13. Growth of polycrystalline InP thin films by the pulsed laser deposition technique

    International Nuclear Information System (INIS)

    The growth of polycrystalline InP films on glass substrates by the pulsed laser deposition technique is reported. Optimal growth conditions as high vacuum and relatively low substrate temperature were necessary to obtain stoichiometric InP layers. Structural and morphological characterizations of the samples are shown. X-ray diffraction shows that the stoichiometric InP films were face-centered cubic with preferred orientation of the crystallites over the (111) plane and mean grain size of about 60 nm. We also discuss the consequences of adverse growth conditions as bad vacuum and high substrate temperature on the film stoichiometry

  14. Growth of polycrystalline InP thin films by the pulsed laser deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Iribarren, A. [Instituto de Materiales y Reactivos, Universidad de La Habana, Zapata y G, Vedado, Plaza, Havana 10400 (Cuba)]. E-mail: augusto@fisica.uh.cu; Castro-Rodriguez, R. [Applied Physics Department, CINVESTAV-IPN Merida, C.P. 97310, Merida Yucatan (Mexico); Ponce-Cabrera, L. [CICATA-IPN, Altamira, Km. 14.5 Carretera Tampico-Puerto Industrial, Altamira 89600, Tamps. (Mexico); Pena, J.L. [Applied Physics Department, CINVESTAV-IPN Merida, C.P. 97310, Merida Yucatan (Mexico)

    2006-07-03

    The growth of polycrystalline InP films on glass substrates by the pulsed laser deposition technique is reported. Optimal growth conditions as high vacuum and relatively low substrate temperature were necessary to obtain stoichiometric InP layers. Structural and morphological characterizations of the samples are shown. X-ray diffraction shows that the stoichiometric InP films were face-centered cubic with preferred orientation of the crystallites over the (111) plane and mean grain size of about 60 nm. We also discuss the consequences of adverse growth conditions as bad vacuum and high substrate temperature on the film stoichiometry.

  15. The "Hoover" (vacuum cleaner technique for calcifying tendonitis deposits excision and removal of the calcific debris

    Directory of Open Access Journals (Sweden)

    Atoun Ehud

    2012-01-01

    Full Text Available A new technical tip for the improvement of the arthroscopic treatment of symptomatic calcifying tendinitis is described. Arthroscopic excision of calcifying tendonitis may result with multiple minute calcific debris in the subacromial bursa, causing severe post operative pain due to chemical irritation of the bursa. We suggest the use of a bladeless shaver barrel as a "Hoover" (vacuum cleaner for arthroscopic clearance of these miniature calcific debris from the subacromial space after resection of the major deposits. The use of this technique resulted in good clinical outcome with improved post operative pain.

  16. Synthesis and characterization of Bi1−xNdxFeO3 thin films deposited using a high throughput physical vapour deposition technique

    International Nuclear Information System (INIS)

    The high throughput synthesis of BiFeO3 and rare earth doped BiFeO3 films using a modified molecular beam epitaxy technique is reported. Optimum conditions for deposition have been established and compositionally graded Bi(1−x)NdxFeO3 (x = 0.08 to 0.24) thin films have been fabricated on platinised silicon substrate (Si/SiO2/TiO2/Pt) with the aim of finding the optimum Nd dopant concentrations for enhanced piezoelectric properties. For x < 0.12, the structure and symmetry were identical to that of the R3c BiFeO3 end member. For x > 0.20, the structure and symmetry were consistent with the NdFeO3 end member (Pnma). For compositions 0.12 < x < 0.2, a gradual transition from R3c to Pnma was observed via a mixed phase region but no compositional interval could be unambiguously identified in which the intermediate PbZrO3-like structure, reported by Karimi et al. (2009) [6], existed as a single phase. Piezoresponse force microscopy remanent hysteresis measurements of the film revealed a statistical increase in the piezoelectric response at x ≈ 0.11 within the R3c region adjacent to the mixed phase field. - Highlights: ► High throughput synthesis and characterization of BiFeO3 and Nd-doped BiFeO3 films ► The piezoelectric properties of compositionally graded bismuth ferrite are studied. ► The structure and phase assemblage of Nd-doped bismuth ferrite have been studied

  17. Deposition of (ZnO:In) TCO Thin Film on Glass Substrate Using DC Sputtering Technique

    International Nuclear Information System (INIS)

    The (ZnO:In) TCO film has been deposited on glass structure using DC sputtering technique. The objective of this research is to study the effect of time deposition, gas pressure, substrate temperature, impurity of In on the resistance, transmittance, micro structure and crystal structure of (ZnO:In) thin film, so that it can be used as a CIS solar cell. The ZnO main target and In pinhole target was bombarded by Ar ion, so that the Zn, O, In atoms were sputtered and form thin film of (ZnO:In) on glass substrate. The resistance were measured using digital ohm meter, the transmittance using UV-Vis, micro structure and thickness using SEM and the crystal structure using XRD. The experiment results, show that the minimum resistance is 0.334 kΩ this obtained at the process parameter on 75 min of time deposition, 5x10-2 Torr of gas pressure, 225℃ of substrate temperature and 8% of content In. The maximum transmittance is 80% at the wave length in (400-900) nm, while the crystal structure of ZnO and In thin film were oriented at the plane ( 0 0 4 ); ( 2 0 2 ) and ( 3 0 1 ). The surface morphology were distributed homogeneously with the thickness of the thin film was in order of 0.41 µm. (author)

  18. Investigation on vanadium oxide thin films deposited by spray pyrolysis technique

    Science.gov (United States)

    Margoni, Mudaliar Mahesh; Mathuri, S.; Ramamurthi, K.; Babu, R. Ramesh; Sethuraman, K.

    2016-05-01

    Vanadium oxide thin films were deposited at 400 °C by spray pyrolysis technique using 0.1 M aqueous precursor solution of ammonium meta vanadate (AMV) with two different pH values. X-ray diffraction results showed that the film prepared using aqueous precursor AMV solution (solution A; pH 7) is amorphous in nature and the film prepared by adding HNO3 in the AMV aqua solution A (solution B; pH 3) is polycrystalline in nature. Vanadium oxide film prepared from the precursor solution B is in the mixed phases of V2O5 and V4O7. Crystallinity is improved for the film prepared using solution B when compared to film prepared from solution A. Crystallite size, strain and dislocation density calculated for the film prepared from solution B is respectively 72.1 nm, 0.4554 × 10-3 lin.-2m-4 and 1.7263 × 1014 lin.m-2. Morphology study revealed that the size of the flakes formed on the surface of the films is influenced by the pH of the precursor solution. Average Visible Transmittance and maximum transmittance of the deposited films exceed 70% and the direct optical band gap value calculated for the films deposited from A and B solution is 1.91 eV and 2.08 eV respectively.

  19. Effects of deposition conditions on gas-barrier performance of SiOxNy thin films formed via ion-beam-assisted vapor deposition

    International Nuclear Information System (INIS)

    SiOxNy thin films were synthesized via ion-beam-assisted vapor deposition (IVD) where deposition of SiOx was irradiated by nitrogen ions. Firstly, reasonable-cost evaporation materials showing less splashing for the SiOx films were investigated by selecting appropriate sintering condition regimes of Si and SiO2 mixed powders. The SiOxNy thin films on a polyethylene terephtalate film substrate obtained via IVD showed a low oxygen transmission rate (OTR) of less than 1 cm3/m2 day. Effective nitrogen ion irradiation energy per atom was 8 eV/at. or greater, which is consistent with regimes where densification of thin films is reported to occur. Higher N2 partial pressure yielded a lower OTR and a higher nitrogen atomic ratio of the films obtained. It is suggested that the improvement in gas-barrier performance resulted from densification and chemical change of the films due to energy addition and nitrification produced by nitrogen ion-beam irradiation

  20. Hybrid solar cells using CdS thin films deposited via spray pyrolysis technique

    International Nuclear Information System (INIS)

    The paper presents the photovoltaic performance of hybrid solar cells comprising of thin films of cadmium sulphide and poly(3-hexyl)thiophene. Cadmium sulphide thin films were deposited using spray pyrolysis technique. Current-voltage characterizations were performed for cadmium sulphide/poly(3-hexyl)thiophene heterojunctions in dark and under illumination (100 mWcm−2). The best device yields a short circuit current density of 1.54 mA/cm2, an open circuit voltage of 343 mV, and a power conversion efficiency of 0.15%. - Highlights: • Hybrid solar cells were fabricated using CdS and poly(3-hexyl)thiophene. • CdS thin films were grown by spray pyrolysis technique. • The best cell performance was achieved for the 100 nm thick CdS films. • The highest short circuit current was measured as 1.54 mAcm−2 for the best cell