WorldWideScience

Sample records for beam sputtering techniques

  1. Development of ion beam sputtering techniques for actinide target preparation

    International Nuclear Information System (INIS)

    Aaron, W.S.; Zevenbergen, L.A.; Adair, H.L.

    1985-01-01

    Ion beam sputtering is a routine method for the preparation of thin films used as targets because it allows the use of minimum quantity of starting material, and losses are much lower than most other vacuum deposition techniques. Work is underway in the Isotope Research Materials Laboratory (IRML) at ORNL to develop the techniques that will make the preparation of actinide targets up to 100 μg/cm 2 by ion beam sputtering a routinely available service from IRML. The preparation of the actinide material in a form suitable for sputtering is a key to this technique, as is designing a sputtering system that allows the flexibility required for custom-ordered target production. At present, development work is being conducted on low-activity in a bench-top system. The system will then be installed in a hood or glove box approved for radioactive materials handling where processing of radium, actinium, and plutonium isotopes among others will be performed. (orig.)

  2. Development of ion beam sputtering techniques for actinide target preparation

    Science.gov (United States)

    Aaron, W. S.; Zevenbergen, L. A.; Adair, H. L.

    1985-06-01

    Ion beam sputtering is a routine method for the preparation of thin films used as targets because it allows the use of a minimum quantity of starting material, and losses are much lower than most other vacuum deposition techniques. Work is underway in the Isotope Research Materials Laboratory (IRML) at ORNL to develop the techniques that will make the preparation of actinide targets up to 100 μg/cm 2 by ion beam sputtering a routinely available service from IRML. The preparation of the actinide material in a form suitable for sputtering is a key to this technique, as is designing a sputtering system that allows the flexibility required for custom-ordered target production. At present, development work is being conducted on low-activity actinides in a bench-top system. The system will then be installed in a hood or glove box approved for radioactive materials handling where processing of radium, actinium, and plutonium isotopes among others will be performed.

  3. Titanium carbide coatings on molybdenum by means of reactive sputtering and electron beam techniques

    International Nuclear Information System (INIS)

    Obata, T.; Aida, H.; Hirohata, Y.; Mohri, M.; Yamashina, T.

    1982-01-01

    This study is an experimental investigation of TiC coatings on Mo substrate by means of a reactive r.f. sputtering in the presence of CH 4 and a chemical reaction with interdiffusion in the sandwich structure of Ti/C/Mo by electron beam evaporation and heating. Using the reactive sputtering method, a homogeneous TiC coating with stoichiometric composition and good adhesion could be produced in the conditions of the partial pressure range of CH 4 , 2 approx. equal to 5 x 10 -4 Torr (total pressure, Psub(Ar) + Psub(CH) 4 = 5.6 x 10 -2 Torr) at 300 0 C (substrate). By using the electron beams, successively evaporated carbon and Ti on a Mo substrate was heated to 700 0 C to form a TiC surface layer on the top which then remained stable during further heating to 1000 0 C. Godd adhesion was brought about by interdiffusion to produce Mo 2 C layer between TiC layer and Mo substrate. It was also found that further heating of the coating layers subsequent to Ti evaporation on the TiC layer produced thicker TiC layer due to a chemical reaction between Ti and inner carbon layers. This could be a promising method of in situ replenishment for TiC coatings on the first wall and the limiter materials. (orig.)

  4. Study of Sb/SnO{sub 2} bi-layer films prepared by ion beam sputtering deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chun-Min [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Huang, Chun-Chieh [Department of Electrical Engineering, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Township, Kaohsiung 833, Taiwan, ROC (China); Kuo, Jui-Chao [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Huang, Jow-Lay, E-mail: jlh888@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 811, Taiwan, ROC (China); Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 701, Taiwan, ROC (China)

    2014-11-03

    In the present work, bi-layer thin films of Sb/SnO{sub 2} 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 SnO{sub 2} layers having thicknesses of 40 nm to 115 nm. The effect of thickness was studied on the morphological, electrical and optical properties. The Sb/SnO{sub 2} 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{sup −3} Ω cm and an optical transmittance of 26% for Sb film having 10 nm thickness. - Highlights: • Bi-layer Sb/SnO{sub 2} 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.

  5. Temperature dependence of InN film deposition by an RF plasma-assisted reactive ion beam sputtering deposition technique

    International Nuclear Information System (INIS)

    Shinoda, Hiroyuki; Mutsukura, Nobuki

    2005-01-01

    Indium nitride (InN) films were deposited on Si(100) substrates using a radiofrequency (RF) plasma-assisted reactive ion beam sputtering deposition technique at various substrate temperatures. The X-ray diffraction patterns of the InN films suggest that the InN films deposited at substrate temperatures up to 370 deg C were cubic crystalline InN; and at 500 deg C, the InN film was hexagonal crystalline InN. In a scanning electron microscope image of the InN film surface, facets of cubic single-crystalline InN grains were clearly observed on the InN film deposited at 370 deg C. The inclusion of metallic indium appeared on the InN film deposited at 500 deg C

  6. Ion beam sputter implantation method

    International Nuclear Information System (INIS)

    King, W.J.

    1978-01-01

    By means of ion beam atomizing or sputtering an integrally composed coating, the composition of which continuously changes from 100% of the substrate to 100% of the coating, can be surfaced on a substrate (e.g. molten quartz on plastic lenses). In order to do this in the facility there is directed a primary beam of accelerated noble gas ions on a target from the group of the following materials: SiO 2 , Al 2 O 3 , Corning Glass 7070, Corning Glass 7740 or borosilicate glass. The particles leaving the target are directed on the substrate by means of an acceleration potential of up to 10 KV. There may, however, be coated also metal layers (Ni, Co) on a mylar film resulting in a semireflecting metal film. (RW) [de

  7. Tests of a new axial sputtering technique in an ECRIS

    International Nuclear Information System (INIS)

    Scott, R.; Pardo, R.; Vondrasek, R.

    2012-01-01

    Axial and radial sputtering techniques have been used over the years to create beams from an ECRIS at multiple accelerator facilities. Operational experience has shown greater beam production when using the radial sputtering method versus axial sputtering. At Argonne National Laboratory, previous work with radial sputtering has demonstrated that the position of the sputter sample relative to the plasma chamber wall influences sample drain current, beam production and charge state distribution. The possibility of the chamber wall acting as a ground plane which influences the sputtering of material has been considered, and an attempt has been made to mimic this possible ground plane effect with a coaxial sample introduced from the injection end. Results of these tests will be shown as well as comparisons of outputs using the two methods. The paper is followed by the associated poster. (authors)

  8. 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.

  9. Preliminary results on adhesion improvement using Ion Beam Sputtering Deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yonggi; Kim, Bomsok; Lee, Jaesang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    Sputtering is an established technique for depositing films with smooth surfaces and interfaces and good thick control. Ejection of articles from a condensed matter due to impingement of high energy particles, termed as sputtering was observed as early as in 1852, however, it is only recently that the complex process of sputtering system. Coating adhesion and environmental stability of the ion beam sputtering deposition coatings performed very well. High-energy high-current ion beam thin film synthesis of adhesion problems can be solved by using. Enhancement of adhesion in thin film synthesis, using high energy and high current ion beam, of mobile phones, car parts and other possible applications in the related industry Alternative technology of wet chrome plating, considering environment and unit cost, for car parts and esthetic improvement on surface of domestic appliances.

  10. Preliminary results on adhesion improvement using Ion Beam Sputtering Deposition

    International Nuclear Information System (INIS)

    Kim, Yonggi; Kim, Bomsok; Lee, Jaesang

    2013-01-01

    Sputtering is an established technique for depositing films with smooth surfaces and interfaces and good thick control. Ejection of articles from a condensed matter due to impingement of high energy particles, termed as sputtering was observed as early as in 1852, however, it is only recently that the complex process of sputtering system. Coating adhesion and environmental stability of the ion beam sputtering deposition coatings performed very well. High-energy high-current ion beam thin film synthesis of adhesion problems can be solved by using. Enhancement of adhesion in thin film synthesis, using high energy and high current ion beam, of mobile phones, car parts and other possible applications in the related industry Alternative technology of wet chrome plating, considering environment and unit cost, for car parts and esthetic improvement on surface of domestic appliances

  11. Influence of ion beam and geometrical parameters on properties of Si thin films grown by Ar ion beam sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Bundesmann, Carsten; Feder, Rene; Neumann, Horst [Leibniz-Institut fuer Oberflaechenmodifizierung e.V., Leipzig (Germany)

    2012-07-01

    Ion beam sputtering (IBS) offers, in contrast to other physical vapour deposition techniques, such as magnetron sputtering or electron beam evaporation, the opportunity to change the properties of the layer forming particles (sputtered and scattered particles) by varying ion beam parameters (ion species, ion energy) and geometrical parameters (ion incidence angle, emission angle). Consequently, these effects can be utilized to tailor thin film properties [1]. The goal is to study systematically the correlations between the primary and secondary parameters and, at last, the effects on the properties of Si thin films, such as optical properties, stress, surface topography and composition. First experimental results are presented for Ar-ion sputtering of Si.

  12. Ion beam sputter coatings for laser technology

    Science.gov (United States)

    Ristau, Detlev; Gross, Tobias

    2005-09-01

    The initial motivation for the development of Ion Beam Sputtering (IBS) processes was the need for optical coatings with extremely low optical scatter losses for laser gyros. Especially, backscattering of the gyro-mirrors couples the directional modes in the ring resonator leading to the lock in effect which limits the sensitivity of the gyro. Accordingly, the first patent on IBS was approved for an aircraft company (Litton) in 1978. In the course of the rapid development of the IBS-concept during the last two decades, an extremely high optical quality could be achieved for laser coatings in the VIS- and NIR-spectral region. For example, high reflecting coatings with total optical losses below 1 ppm were demonstrated for specific precision measurement applications with the Nd:YAG-laser operating at 1.064 μm. Even though the high quality level of IBS-coatings had been confirmed in many applications, the process has not found its way into the production environment of most optical companies. Major restrictions are the relatively low rate of the deposition process and the poor lateral homogeneity of the coatings, which are related to the output characteristics of the currently available ion sources. In the present contribution, the basic principles of IBS will be discussed in the context of the demands of modern laser technology. Besides selected examples for special applications of IBS, aspects will be presented for approaches towards rapid manufacturing of coatings and the production of rugate filters on the basis of IBS-techniques.

  13. Improving depth resolutions in positron beam spectroscopy by concurrent ion-beam sputtering

    Science.gov (United States)

    John, Marco; Dalla, Ayham; Ibrahim, Alaa M.; Anwand, Wolfgang; Wagner, Andreas; Böttger, Roman; Krause-Rehberg, Reinhard

    2018-05-01

    The depth resolution of mono-energetic positron annihilation spectroscopy using a positron beam is shown to improve by concurrently removing the sample surface layer during positron beam spectroscopy. During ion-beam sputtering with argon ions, Doppler-broadening spectroscopy is performed with energies ranging from 3 keV to 5 keV allowing for high-resolution defect studies just below the sputtered surface. With this technique, significantly improved depth resolutions could be obtained even at larger depths when compared to standard positron beam experiments which suffer from extended positron implantation profiles at higher positron energies. Our results show that it is possible to investigate layered structures with a thickness of about 4 microns with significantly improved depth resolution. We demonstrated that a purposely generated ion-beam induced defect profile in a silicon sample could be resolved employing the new technique. A depth resolution of less than 100 nm could be reached.

  14. Nanofabrication by ion-beam sputtering fundamentals and applications

    CERN Document Server

    Som, Tapobrata

    2012-01-01

    Considerable attention has been paid to ion beam sputtering as an effective way to fabricate self-organized nano-patterns on various substrates. The significance of this method for patterning surfaces is that the technique is fast, simple, and less expensive. The possibility to create patterns on very large areas at once makes it even more attractive. This book reviews various fascinating results, understand the underlying physics of ion induced pattern formation, to highlight the potential applications of the patterned surfaces, and to explore the patterning behavior by different irradiation

  15. Development of ion beam sputtering technology for mold and die

    International Nuclear Information System (INIS)

    Lee, Jaehyung; Park, J.; Lee, J.; Jil, J.; Yang, D.; Noh, Y.; You, B.; You, J.

    2003-06-01

    Ion beam sputtering technique, one of the surface modification techniques, is to reduce surface roughness of materials with selective detaching atoms and micro particles from the surface by bombarding energetic ions of a few to a few tens keV onto the materials surfaces. This technique can be applied for the surfaces that need to have sub micrometer surface roughness, and it has already been used by companies and/or Institute over the world. Although this is relatively high cost process, it has been widely demanded in the industries with developing the eco-friend equipment due to its high quality of products. In the domestic industry, it has been pointed out that the mechanical polishing technique for molds and dies is relatively expensive and does not produce the required surface roughness. Therefore, in this R and D, techniques obtained from the ion source and the ion beam irradiation techniques developed for the proton accelerator has been applied to polish the surface of molds and dies to solve the above-mentioned problems that take place during mechanical polishing. In case that ion beam polishing technique is used, we expect not only producing the high quality polished surfaces but also producing the economically valuable end-products. In this R and D project, we are aiming at establishing ion beam techniques for industrialization as well as mass production of low cost products with developing the economical instrumentation techniques. Also, as a result of this R and D it is expected that importing of precise molds and dies may be reduced and technical competitiveness will be enhanced

  16. Orientation-dependent ion beam sputtering at normal incidence conditions in FeSiAl alloy

    International Nuclear Information System (INIS)

    Batic, Barbara Setina; Jenko, Monika

    2010-01-01

    The authors have performed Ar+ broad ion beam sputtering of a polycrystalline Fe-Si-Al alloy at normal incidence at energies varying from 6 to 10 keV. Sputtering results in the formation of etch pits, which can be classified in three shapes: triangular, rectangular, and square. As each grain of individual orientation exhibits a certain type of pattern, the etch pits were correlated with the crystal orientations by electron backscattered diffraction technique.

  17. Characterization of copper thin films prepared by metal self-ion beam sputter deposition

    International Nuclear Information System (INIS)

    Gotoh, Yasuhito; Amioka, Takao; Tsuji, Hiroshi; Ishikawa, Junzo

    1994-01-01

    New deposition technique, 'metal-ion beam self-sputtering' method has been developed. Using metal ions which is the same element with the target material, no contamination with noble gas atoms, which are often used in the conventional sputtering, will occur. In this paper, fundamental measurement of the film purity is reported. As a result of PIXE measurements, it was clarified that only slight amount of iron is incorporated in the films. (author)

  18. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A; Laird, J S; Bardos, R A; Legge, G J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T; Sekiguchi, H [Electrotechnical Laboratory, Tsukuba (Japan).

    1994-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  19. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A.; Laird, J.S.; Bardos, R.A.; Legge, G.J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T.; Sekiguchi, H. [Electrotechnical Laboratory, Tsukuba (Japan).

    1993-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  20. Nanopatterning of swinging substrates by ion-beam sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sun Mi; Kim, J.-S., E-mail: jskim@sm.ac.kr [Department of Physics, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of)

    2016-05-28

    Graphite substrates are azimuthally swung during ion-beam sputtering (IBS) at a polar angle θ = 78° from the surface normal. The swinging of the substrate not only causes quasi-two-dimensional mass transport but also makes various sputter effects from the different incident angles to work together. Through variation of the swing angle, both the transport and sputtering effects synergistically produce a series of salient patterns, such as asymmetric wall-like structures, which can grow to several tens of nanometers and exhibit a re-entrant orientational change with the increased swing angle. Thus, the present work demonstrates that dynamic variables such as the swing angle, which have been little utilized, offer an additional parameter space that can be exploited to diversify the sputtered patterns, thereby expanding the applicability of an IBS as well as the comprehension of the IBS nano patterning mechanism.

  1. Nanopatterning of swinging substrates by ion-beam sputtering

    International Nuclear Information System (INIS)

    Yoon, Sun Mi; Kim, J.-S.

    2016-01-01

    Graphite substrates are azimuthally swung during ion-beam sputtering (IBS) at a polar angle θ = 78° from the surface normal. The swinging of the substrate not only causes quasi-two-dimensional mass transport but also makes various sputter effects from the different incident angles to work together. Through variation of the swing angle, both the transport and sputtering effects synergistically produce a series of salient patterns, such as asymmetric wall-like structures, which can grow to several tens of nanometers and exhibit a re-entrant orientational change with the increased swing angle. Thus, the present work demonstrates that dynamic variables such as the swing angle, which have been little utilized, offer an additional parameter space that can be exploited to diversify the sputtered patterns, thereby expanding the applicability of an IBS as well as the comprehension of the IBS nano patterning mechanism.

  2. Towards a magnetic field separation in Ion Beam Sputtering processes

    Energy Technology Data Exchange (ETDEWEB)

    Malobabic, Sina, E-mail: s.malobabic@lzh.de [Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover (Germany); Quest: Centre of Quantum Engineering and Space-Time Research, Leibniz Universität Hannover (Germany); Jupé, Marco [Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover (Germany); Quest: Centre of Quantum Engineering and Space-Time Research, Leibniz Universität Hannover (Germany); Kadhkoda, Puja [Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover (Germany); Ristau, Detlev [Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover (Germany); Quest: Centre of Quantum Engineering and Space-Time Research, Leibniz Universität Hannover (Germany)

    2015-10-01

    Defects embedded in coatings due to particle contamination are considered as a primary factor limiting the quality of optical coatings in Ion Beam Sputtering. An approach combining the conventional Ion Beam Sputtering process with a magnetic separator in order to remove these particles from film growth is presented. The separator provides a bent axial magnetic field that guides the material flux towards the substrate positioned at the exit of the separator. Since there is no line of sight between target and substrate, the separator prevents that the particles generated in the target area can reach the substrate. In this context, optical components were manufactured that reveal a particle density three times lower than optical components which were deposited using a conventional Ion Beam Sputtering process. - Highlights: • We use bent magnetic fields to guide and separate the sputtered deposition material. • No line of sight between substrate and target prevents thin films from particles. • The transport efficiency of binary and ternary oxides is investigated. • The defect statistics of manufactured dielectric ternary multilayers are evaluated. • The phase separation leads to a drastically reduction of particle contamination.

  3. Studies on ion scattering and sputtering processes relevant to ion beam sputter deposition of multicomponent thin films

    International Nuclear Information System (INIS)

    Auciello, O.; Ameen, M.S.; Kingon, A.I.

    1989-01-01

    Results from computer simulation and experiments on ion scattering and sputtering processes in ion beam sputter deposition of high Tc superconducting and ferroelectric thin films are presented. It is demonstrated that scattering of neutralized ions from the targets can result in undesirable erosion of, and inert gas incorporation in, the growing films, depending on the ion/target atom ass ratio and ion beam angle of incidence/target/substrate geometry. The studies indicate that sputtering Kr + or Xe + ions is preferable to the most commonly used Ar + ions, since the undesirable phenomena mentioned above are minimized for the first two ions. These results are used to determine optimum sputter deposition geometry and ion beam parameters for growing multicomponent oxide thin films by ion beam sputter-deposition. 10 refs., 5 figs

  4. Advanced electron beam techniques

    International Nuclear Information System (INIS)

    Hirotsu, Yoshihiko; Yoshida, Yoichi

    2007-01-01

    After 100 years from the time of discovery of electron, we now have many applications of electron beam in science and technology. In this report, we review two important applications of electron beam: electron microscopy and pulsed-electron beam. Advanced electron microscopy techniques to investigate atomic and electronic structures, and pulsed-electron beam for investigating time-resolved structural change are described. (author)

  5. Sputtering of silicon and glass substrates with polyatomic molecular ion beams generated from ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Mitsuaki, E-mail: m-takeuchi@kuee.kyoto-u.ac.jp; Hoshide, Yuki; Ryuto, Hiromichi; Takaoka, Gikan H. [Photonics and Electronics Science and Engineering Center, Kyoto University, Kyotodaigaku-Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan)

    2016-03-15

    The effect of irradiating 1-ethyl-3-methylimidazolium positive (EMIM{sup +}) or dicyanamide negative (DCA{sup –}) ion beams using an ionic liquid ion source was characterized concerning its sputtering properties for single crystalline Si(100) and nonalkaline borosilicate glass substrates. The irradiation of the DCA{sup –} ion beam onto the Si substrate at an acceleration voltage of 4 and 6 kV exhibited detectable sputtered depths greater than a couple of nanometers with an ion fluence of only 1 × 10{sup 15} ions/cm{sup 2}, while the EMIM{sup +} ion beam produced the same depths with an ion fluence 5 × 10{sup 15} ions/cm{sup 2}. The irradiation of a 4 kV DCA{sup –} ion beam at a fluence of 1 × 10{sup 16} ions/cm{sup 2} also yields large etching depths in Si substrates, corresponding to a sputtering yield of Si/DCA{sup – }= 10, and exhibits a smoothed surface roughness of 0.05 nm. The interaction between DCA{sup –} and Si likely causes a chemical reaction that relates to the high sputtering yield and forms an amorphous C-N capping layer that results in the smooth surface. Moreover, sputtering damage by the DCA{sup –} irradiation, which was estimated by Rutherford backscattering spectroscopy with the channeling technique, was minimal compared to Ar{sup +} irradiation at the same condition. In contrast, the glass substrates exhibited no apparent change in surface roughnesses when sputtered by the DCA{sup –} irradiation compared to the unirradiated glass substrates.

  6. Ion beam and dual ion beam sputter deposition of tantalum oxide films

    Science.gov (United States)

    Cevro, Mirza; Carter, George

    1994-11-01

    Ion beam sputter deposition (IBS) and dual ion beam sputter deposition (DIBS) of tantalum oxide films was investigated at room temperature and compared with similar films prepared by e-gun deposition. Optical properties ie refractive index and extinction coefficient of IBS films were determined in the 250 - 1100 nm range by transmission spectrophotometry and at (lambda) equals 632.8 nm by ellipsometry. They were found to be mainly sensitive to the partial pressure of oxygen used as a reactive gas in the deposition process. The maximum value of the refractive index of IBS deposited tantalum oxide films was n equals 2.15 at (lambda) equals 550 nm and the extinction coefficient of order k equals 2 X 10-4. Films deposited by e-gun deposition had refractive index n equals 2.06 at (lambda) equals 550 nm. Films deposited using DIBS ie deposition assisted by low energy Ar and O2 ions (Ea equals 0 - 300 eV) and low current density (Ji equals 0 - 40 (mu) A/cm2) showed no improvement in the optical properties of the films. Preferential sputtering occurred at Ea(Ar) equals 300 eV and Ji equals 20 (mu) A/cm2 and slightly oxygen deficient films were formed. Different bonding states in the tantalum-oxide films were determined by x-ray spectroscopy while composition of the film and contaminants were determined by Rutherford scattering spectroscopy. Tantalum oxide films formed by IBS contained relatively high Ar content (approximately equals 2.5%) originating from the reflected argon neutrals from the sputtering target while assisted deposition slightly increased the Ar content. Stress in the IBS deposited films was measured by the bending technique. IBS deposited films showed compressive stress with a typical value of s equals 3.2 X 109 dyn/cm2. Films deposited by concurrent ion bombardment showed an increase in the stress as a function of applied current density. The maximum was s approximately equals 5.6 X 109 dyn/cm2 for Ea equals 300 eV and Ji equals 35 (mu) A/cm2. All

  7. Ion-beam and dual-ion-beam sputter deposition of tantalum oxide films

    Science.gov (United States)

    Cevro, Mirza; Carter, George

    1995-02-01

    Ion-beam sputter deposition (IBS) and dual-ion-beam sputter deposition (DIBS) of tantalum oxide films was investigated at room temperature and compared with similar films prepared by e-gun deposition. The optical properties, i.e., refractive index and extinction coefficient, of IBS films were determined in the 250- to 1100-nm range by transmission spectrophotometry and at (lambda) equals 632.8 nm by ellipsometry. They were found to be mainly sensitive to the partial pressure of oxygen used as a reactive gas in the deposition process. The maximum value of the refractive index of IBS deposited tantalum oxide films was n equals 2.15 at (lambda) equals 550 nm and the extinction coefficient of order k equals 2 X 10-4. Films deposited by e-gun deposition had refractive index n 2.06 at (lambda) equals 550 nm. Films deposited using DIBS, i.e., deposition assisted by low energy Ar and O2 ions (Ea equals 0 to 300 eV) and low current density (Ji equals 0 to 40 (mu) A/cm2), showed no improvement in the optical properties of the films. Preferential sputtering occurred at Ea(Ar) equals 300 eV and Ji equals 20 (mu) A/cm2 and slightly oxygen deficient films were formed. Different bonding states in the tantalum-oxide films were determined by x-ray spectroscopy, whereas composition of the film and contaminants were determined by Rutherford backscattering spectroscopy (RBS). Tantalum oxide films formed by IBS contained relatively high Ar content (approximately equals 2.5%) originating from the reflected argon neutrals from the sputtering target whereas assisted deposition slightly increased the Ar content. Stress in the IBS-deposited films was measured by the bending technique. IBS-deposited films showed compressive stress with a typical value of s equals 3.2 X 109 dyn/cm2. Films deposited by concurrent ion bombardment showed an increase in the stress as a function of applied current density. The maximum was s approximately equals 5.6 X 109 dyn/cm2 for Ea equals 300 eV and Ji equals

  8. Pattern evolution during ion beam sputtering; reductionistic view

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.-H.; Kim, J.-S., E-mail: jskim@sm.ac.kr

    2016-09-15

    The development of the ripple pattern during the ion beam sputtering (IBS) is expounded via the evolution of its constituent ripples. For that purpose, we perform numerical simulation of the ripple evolution that is based on Bradley–Harper model and its non-linear extension. The ripples are found to evolve via various well-defined processes such as ripening, averaging, bifurcation and their combinations, depending on their neighboring ripples. Those information on the growth kinetics of each ripple allow the detailed description of the pattern development in real space that the instability argument and the diffraction study both made in k-space cannot provide.

  9. Superconducting oxide thin films by ion beam sputtering

    International Nuclear Information System (INIS)

    Kobrin, P.H.; DeNatale, J.F.; Housley, R.M.; Flintoff, J.F.; Harker, A.B.

    1987-01-01

    Superconducting thin films of ternary copper oxides from the Y-Ba-Cu-O and La-Sr-Cu-O systems have been deposited by ion beam sputtering of ceramic targets. Crystallographic orientation of the polycrystalline films has been shown to vary with substrate identity, deposition temperature and annealing temperature. The onset of the superconductive transition occurs near 90K in the Y-Ba-Cu-O system. Fe impurities of < 0.2% have been found to inhibit the superconducting transition, probably by migrating to the grain boundaries

  10. Technology and applications of broad-beam ion sources used in sputtering. Part II. Applications

    International Nuclear Information System (INIS)

    Harper, J.M.E.; Cuomo, J.J.; Kaufman, H.R.

    1982-01-01

    The developments in broad-beam ion source technology described in the companion paper (Part I) have stimulated a rapid expansion in applications to materials processing. These applications are reviewed here, beginning with a summary of sputtering mechanisms. Next, etching applications are described, including microfabrication and reactive ion beam etching. The developing area of surface layer applications is summarized, and related to the existing fields of oxidation and implantation. Next, deposition applications are reviewed, including ion-beam sputter deposition and the emerging technique of ion-assisted vapor deposition. Many of these applications have been stimulated by the development of high current ion sources operating in the energy range of tens of hundreds of eV. It is in this energy range that ion-activated chemical etching is efficient, self-limiting compound layers can be grown, and the physical properties of vapor-deposited films can be modified. In each of these areas, broad ion beam technology provides a link between other large area plasma processes and surface analytical techniques using ion beams

  11. ITO/InP solar cells: A comparison of devices fabricated by ion beam and RF sputtering of the ITO

    Science.gov (United States)

    Coutts, T. J.

    1987-01-01

    This work was performed with the view of elucidating the behavior of indium tin oxide/indium phosphide (ITO/InP) solar cells prepared by RF and ion beam sputtering. It was found that using RF sputter deposition of the ITO always leads to more efficient devices than ion beam sputter deposition. An important aspect of the former technique is the exposure of the single crystal p-InP substrates to a very low plasma power prior to deposition. Substrates treated in this manner have also been used for ion beam deposition of ITO. In this case the cells behave very similarly to the RF deposited cells, thus suggesting that the lower power plasma exposure (LPPE) is the crucial process step.

  12. Differential ion beam sputtering of segregated phases in aluminum casting alloys

    International Nuclear Information System (INIS)

    Nguyen, Chuong L.; Wirtz, Tom; Fleming, Yves; Metson, James B.

    2013-01-01

    Highlights: ► Novel combination of SIMS and SPM for accurate 3D chemical mapping. ► Different removal rates of metallurgical phases by ion beam. ► Faster oxidation rate of silicon vs. aluminum at room temperature in vacuum. - Abstract: Differential sputtering of materials is an important phenomenon in materials science with many implications. One of the practical applications of this phenomenon is the modification of the interface between a substrate and coating during sputter coating of materials. Aluminum casting alloys, as common materials in many applications, are suitable candidates to investigate this phenomenon due to their phase separated microstructures. Changes at the sample surface under ion bombardment can be characterized by a range of complimentary techniques. The novel SIMS–SPM instrument used here enables a thorough investigation into the evolution of topography and composition caused by ion beam sputtering. For the alloy examined in this work, the aluminum regions are removed faster than the silicon particles. The faster oxidation rate of silicon compared to aluminum in the exposed surface can also be deduced from this study.

  13. A review of basic phenomena and techniques for sputter-deposition of high temperature superconducting films

    Energy Technology Data Exchange (ETDEWEB)

    Auciello, O. (Microelectronics Center of North Carolina, Research Triangle Park, NC (USA) North Carolina State Univ., Raleigh, NC (USA). Dept. of Materials Science and Engineering); Ameen, M.S.; Kingon, A.I.; Lichtenwalner, D.J. (North Carolina State Univ., Raleigh, NC (USA). Dept. of Materials Science and Engineering); Krauss, A.R. (Argonne National Lab., IL (USA))

    1990-01-01

    The processes involved in plasma and ion beam sputter-deposition of high temperature 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 produced. Control of film composition is a major issue in sputter-deposition of multicomponent materials. Low temperature processing of films is a common goal for each technique, particularly in relation to integrating high temperature superconducting films with the current microelectronics technology. It has been understood for some time that for Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} deposition, the most intensely studied high-{Tc} compound, incorporation of sufficient oxygen into the film during deposition is necessary to produce as-deposited superconducting films at relatively substrate temperatures. Recent results have shown that with the use of suitable buffer layers, high quality Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} sputtered films can be obtained on Si substrates without the need for post-deposition anneal processing. This review is mainly focussed on issues related to sputter-deposition of Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} thin films, although representative results concerning the bismuth and thallium based compounds are included. 143 refs., 11 figs.

  14. Computer simulation of scattered ion and sputtered species effects in ion beam sputter-deposition of high temperature superconducting thin films

    International Nuclear Information System (INIS)

    Krauss, A.R.; Auciello, O.

    1992-01-01

    Ion beam sputter-deposition is a technique currently used by many groups to produce single and multicomponent thin films. This technique provides several advantages over other deposition methods, which include the capability for yielding higher film density, accurate stoichiometry control, and smooth surfaces. However, the relatively high kinetic energies associated with ion beam sputtering also lead to difficulties if the process is not properly controlled. Computer simulations have been performed to determine net deposition rates, as well as the secondary erosion, lattice damage, and gas implantation in the films, associated with primary ions scattered from elemental Y, Ba and Cu targets used to produce high temperature superconducting Y-Ba-Cu-O films. The simulations were performed using the TRIM code for different ion masses and kinetic energies, and different deposition geometries. Results are presented for primary beams of Ar + , Kr + and Xe + incident on Ba and Cu targets at 0 degrees and 45 degrees with respect to the surface normal, with the substrate positioned at 0 degrees and 45 degrees. The calculations indicate that the target composition, mass and kinetic energy of the primary beam, angle of incidence on the target, and position and orientation of the substrate affect the film damage and trapped primary beam gas by up to 5 orders of magnitude

  15. Surfactant Sputtering: Theory of a new method of surface nanostructuring by ion beams

    International Nuclear Information System (INIS)

    Kree, R.; Yasseri, T.; Hartmann, A.K.

    2009-01-01

    We present a new Monte Carlo model and a new continuum theory of surface pattern formation due to 'surfactant sputtering', i.e. erosion by ion beam sputtering including a submonolayer coverage of additional, co-sputtered surfactant atoms. This setup, which has been realized in recent experiments in a controlled way leads to a number of interesting possibilities to modify pattern forming processing conditions. We will present three simple scenarios, which illustrate some potential applications of the method. In all three cases, simple Bradley-Harper type ripples appear in the absence of surfactant, whereas new, interesting structures emerge during surfactant sputtering.

  16. Beam Techniques - Beam Control and Manipulation

    International Nuclear Information System (INIS)

    Minty, Michiko G

    2003-01-01

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization

  17. Beam Techniques - Beam Control and Manipulation

    Energy Technology Data Exchange (ETDEWEB)

    Minty, Michiko G

    2003-04-24

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization.

  18. Simulating discrete models of pattern formation by ion beam sputtering

    International Nuclear Information System (INIS)

    Hartmann, Alexander K; Kree, Reiner; Yasseri, Taha

    2009-01-01

    A class of simple, (2+1)-dimensional, discrete models is reviewed, which allow us to study the evolution of surface patterns on solid substrates during ion beam sputtering (IBS). The models are based on the same assumptions about the erosion process as the existing continuum theories. Several distinct physical mechanisms of surface diffusion are added, which allow us to study the interplay of erosion-driven and diffusion-driven pattern formation. We present results from our own work on evolution scenarios of ripple patterns, especially for longer timescales, where nonlinear effects become important. Furthermore we review kinetic phase diagrams, both with and without sample rotation, which depict the systematic dependence of surface patterns on the shape of energy depositing collision cascades after ion impact. Finally, we discuss some results from more recent work on surface diffusion with Ehrlich-Schwoebel barriers as the driving force for pattern formation during IBS and on Monte Carlo simulations of IBS with codeposition of surfactant atoms.

  19. Magnetic and structural properties of ion beam sputtered Fe–Zr–Nb–B–Cu thin films

    International Nuclear Information System (INIS)

    Modak, S.S.; Kane, S.N.; Gupta, A.; Mazaleyrat, F.; LoBue, M.; Coisson, M.; Celegato, F.; Tiberto, P.; Vinai, F.

    2012-01-01

    Magnetic and structural properties of Fe–Zr–Nb–B–Cu thin films, prepared by ion beam sputtering on silicon substrates by using a target made up of amorphous ribbons of nominal composition Fe 84 Zr 3.5 Nb 3.5 B 8 Cu 1 , are reported. As-deposited thin film samples exhibit an in-plane uniaxial anisotropy, which can be ascribed to the preparation technique and the coupling of quenched-in internal stresses. Structural measurements indicate no significant variation of the grain size with thickness and with the annealing temperature. Increase in surface irregularities with annealing temperature and oxidation results in aggregates that would act as pinning centers, affecting the magnetic properties leading to magnetic hardening of the specimens. The role of the magnetic anisotropy is thoroughly discussed with the help of magnetic and ferromagnetic resonance measurements. - Highlights: ►Ion beam sputtered Fe–Zr–Nb–B–Cu thin films of different thickness are prepared. ►Films exhibit in-plane uniaxial anisotropy, which reduces with thermal treatments. ►Increased surface roughness leads to wall pinning, increasing the coercive field.

  20. Particle beam experiments for the analysis of reactive sputtering processes in metals and polymer surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Corbella, Carles; Grosse-Kreul, Simon; Kreiter, Oliver; Arcos, Teresa de los; Benedikt, Jan; Keudell, Achim von [RD Plasmas with Complex Interactions, Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum (Germany)

    2013-10-15

    A beam experiment is presented to study heterogeneous reactions relevant to plasma-surface interactions in reactive sputtering applications. Atom and ion sources are focused onto the sample to expose it to quantified beams of oxygen, nitrogen, hydrogen, noble gas ions, and metal vapor. The heterogeneous surface processes are monitored in situ by means of a quartz crystal microbalance and Fourier transform infrared spectroscopy. Two examples illustrate the capabilities of the particle beam setup: oxidation and nitriding of aluminum as a model of target poisoning during reactive magnetron sputtering, and plasma pre-treatment of polymers (PET, PP)

  1. Low temperature mechanical dissipation of an ion-beam sputtered silica film

    International Nuclear Information System (INIS)

    Martin, I W; Craig, K; Bassiri, R; Hough, J; Robie, R; Rowan, S; Nawrodt, R; Schwarz, C; Harry, G; Penn, S; Reid, S

    2014-01-01

    Thermal noise arising from mechanical dissipation in oxide mirror coatings is an important limit to the sensitivity of future gravitational wave detectors, optical atomic clocks and other precision measurement systems. Here, we present measurements of the temperature dependence of the mechanical dissipation of an ion-beam sputtered silica film between 10 and 300 K. A dissipation peak was observed at 20 K and the low temperature dissipation was found to have significantly different characteristics than observed for bulk silica and silica films deposited by alternative techniques. These results are important for better understanding the underlying mechanisms of mechanical dissipation, and thus thermal noise, in the most commonly-used reflective coatings for precision measurements. (paper)

  2. Electronic properties of single Ge/Si quantum dot grown by ion beam sputtering deposition.

    Science.gov (United States)

    Wang, C; Ke, S Y; Yang, J; Hu, W D; Qiu, F; Wang, R F; Yang, Y

    2015-03-13

    The dependence of the electronic properties of a single Ge/Si quantum dot (QD) grown by the ion-beam sputtering deposition technique on growth temperature and QD diameter is investigated by conductive atomic force microscopy (CAFM). The Si-Ge intermixing effect is demonstrated to be important for the current distribution of single QDs. The current staircase induced by the Coulomb blockade effect is observed at higher growth temperatures (>700 °C) due to the formation of an additional barrier between dislocated QDs and Si substrate for the resonant tunneling of holes. According to the proposed single-hole-tunneling model, the fact that the intermixing effect is observed to increase as the incoherent QD size decreases may explain the increase in the starting voltage of the current staircase and the decrease in the current step width.

  3. Capability of focused Ar ion beam sputtering for combinatorial synthesis of metal films

    International Nuclear Information System (INIS)

    Nagata, T.; Haemori, M.; Chikyow, T.

    2009-01-01

    The authors examined the use of focused Ar ion beam sputtering (FAIS) for combinatorial synthesis. A Langmuir probe revealed that the electron temperature and density for FAIS of metal film deposition was lower than that of other major combinatorial thin film growth techniques such as pulsed laser deposition. Combining FAIS with the combinatorial method allowed the compositional fraction of the Pt-Ru binary alloy to be systematically controlled. Pt-Ru alloy metal film grew epitaxially on ZnO substrates, and crystal structures changed from the Pt phase (cubic structure) to the Ru phase (hexagonal structure) in the Pt-Ru alloy phase diagram. The alloy film has a smooth surface, with the Ru phase, in particular, showing a clear step-and-terrace structure. The combination of FAIS and the combinatorial method has major potential for the fabrication of high quality composition-spread metal film.

  4. Capability of focused Ar ion beam sputtering for combinatorial synthesis of metal films

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, T.; Haemori, M.; Chikyow, T. [Advanced Electric Materials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2009-05-15

    The authors examined the use of focused Ar ion beam sputtering (FAIS) for combinatorial synthesis. A Langmuir probe revealed that the electron temperature and density for FAIS of metal film deposition was lower than that of other major combinatorial thin film growth techniques such as pulsed laser deposition. Combining FAIS with the combinatorial method allowed the compositional fraction of the Pt-Ru binary alloy to be systematically controlled. Pt-Ru alloy metal film grew epitaxially on ZnO substrates, and crystal structures changed from the Pt phase (cubic structure) to the Ru phase (hexagonal structure) in the Pt-Ru alloy phase diagram. The alloy film has a smooth surface, with the Ru phase, in particular, showing a clear step-and-terrace structure. The combination of FAIS and the combinatorial method has major potential for the fabrication of high quality composition-spread metal film.

  5. Atom beam sputtered Ag-TiO{sub 2} plasmonic nanocomposite thin films for photocatalytic applications

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jaspal; Sahu, Kavita [School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, Dwarka, NewDelhi 110078 (India); Pandey, A. [Solid State Physics Laboratory, Defence Research and Development Organization, Timarpur, Delhi 110054 (India); Kumar, Mohit [Institute of Physics, Sachivalaya Marg, Bhubaneswar, Odisha 751005 (India); Ghosh, Tapas; Satpati, B. [Saha Institute of Nuclear Physics, HBNI, 1/AF, Bidhannagar, Kolkata 700064 (India); Som, T.; Varma, S. [Institute of Physics, Sachivalaya Marg, Bhubaneswar, Odisha 751005 (India); Avasthi, D.K. [Amity Institute of Nanotechnology, Noida 201313, Uttar Pradesh (India); Mohapatra, Satyabrata, E-mail: smiuac@gmail.com [School of Basic and Applied Sciences, Guru Gobind Singh Indraprastha University, Dwarka, NewDelhi 110078 (India)

    2017-07-31

    The development of nanocomposite coatings with highly enhanced photocatalytic activity is important for photocatalytic purification of water and air. We report on the synthesis of Ag-TiO{sub 2} nanocomposite thin films with highly enhanced photocatalytic activity by atom beam co-sputtering technique. The effects of Ag concentration on the structural, morphological, optical, plasmonic and photocatalytic properties of the nanocomposite thin films were investigated. UV–visible DRS studies revealed the presence of surface plasmon resonance (SPR) peak characteristic of Ag nanoparticles together with the excitonic absorption peak originating from TiO{sub 2} nanoparticles in the nanocomposites. XRD studies showed that the nanocomposite thin films consist of Ag nanoparticles and rutile TiO{sub 2} nanoparticles. The synthesized Ag-TiO{sub 2} nanocomposite thin films with 5 at% Ag were found to exhibit highly enhanced photocatalytic activity for sun light driven photocatalytic degradation of methylene blue in water, indicating their potential application in water purification.

  6. Ion beam sputtering of Ti: Influence of process parameters on angular and energy distribution of sputtered and backscattered particles

    Energy Technology Data Exchange (ETDEWEB)

    Lautenschläger, T. [Leibniz-Institute of Surface Modification, 04318 Leipzig (Germany); Feder, R., E-mail: thomas.lautenschlaeger@iom-leipzig.de [Leibniz-Institute of Surface Modification, 04318 Leipzig (Germany); Neumann, H. [Leibniz-Institute of Surface Modification, 04318 Leipzig (Germany); Rice, C.; Schubert, M. [Department of Electrical and Computer Engineering and Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0511 (United States); Bundesmann, C. [Leibniz-Institute of Surface Modification, 04318 Leipzig (Germany)

    2016-10-15

    Highlights: • Ion beam sputter deposition under systematic variation of process parameters. • Angular and energy distribution of secondary particles. • Interaction between incorporated and impinging process gas. • Measured data compared with simulations. - Abstract: In the present study, the influence of ion energy and geometrical parameters onto the angular and energy distribution of secondary particles for sputtering a Ti target with Ar ions is investigated. The angular distribution of the particle flux of the sputtered Ti atoms was determined by the collection method, i.e. by growing Ti films and measuring their thickness. The formal description of the particle flux can be realized by dividing it into an isotropic and an anisotropic part. The experimental data show that increasing the ion energy or decreasing the ion incidence angle lead to an increase of the isotropic part, which is in good agreement with basic sputtering theory. The energy distribution of the secondary ions was measured using an energy-selective mass spectrometer. The energy distribution of the sputtered target ions shows a maximum at an energy between 10 eV and 20 eV followed by a decay proportional to E{sup −n}, which is in principle in accordance with Thompson’s theory, followed by a high energetic tail. When the sum of incidence angle and emission angle is increased, the high-energetic tail expands to higher energies and an additional peak due to direct sputtering events may occur. In the case of backscattered primary Ar ions, a maximum at an energy between 5 eV and 10 eV appears and, depending on the scattering geometry, an additional broad peak at a higher energy due to direct scattering events is observed. The center energy of the additional structure shifts systematically to higher energies with decreasing scattering angle or increasing ion energy. The experimental results are compared to calculations based on simple elastic two-particle-interaction theory and to

  7. Study on the Deposition Rate Depending on Substrate Position by Using Ion Beam Sputtering Deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yonggi; Kim, Bomsok; Lee, Jaesang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Ion beams have been used for over thirty years to modify materials in manufacturing of integrated circuits, and improving the corrosion properties of surfaces. Recently, the requirements for ion beam processes are becoming especially challenging in the following areas : ultra shallow junction formation for LSI fabrication, low damage high rate ion beam sputtering and smoothing, high quality functional surface treatment for electrical and optical properties. Ion beam sputtering is an attractive technology for the deposition of thin film coatings onto a broad variety of polymer, Si-wafer, lightweight substrates. Demand for the decoration metal is increasing. In addition, lightweight of parts is important, because of energy issues in the industries. Although a lot of researches have been done with conventional PVD methods for the deposition of metal or ceramic films on the surface of the polymer, there are still adhesion problems.

  8. Second order nonlinear optical properties of zinc oxide films deposited by low temperature dual ion beam sputtering

    International Nuclear Information System (INIS)

    Larciprete, M.C.; Passeri, D.; Michelotti, F.; Paoloni, S.; Sibilia, C.; Bertolotti, M.; Belardini, A.; Sarto, F.; Somma, F.; Lo Mastro, S.

    2005-01-01

    We investigated second order optical nonlinearity of zinc oxide thin films, grown on glass substrates by the dual ion beam sputtering technique under different deposition conditions. Linear optical characterization of the films was carried out by spectrophotometric optical transmittance and reflectance measurements, giving the complex refractive index dispersion. Resistivity of the films was determined using the four-point probe sheet resistance method. Second harmonic generation measurements were performed by means of the Maker fringes technique where the fundamental beam was originated by nanosecond laser at λ=1064 nm. We found a relatively high nonlinear optical response, and evidence of a dependence of the nonlinear coefficient on the deposition parameters for each sample. Moreover, the crystalline properties of the films were investigated by x-ray diffraction measurements and correlation with second order nonlinearity were analyzed. Finally, we investigated the influence of the oxygen flow rate during the deposition process on both the second order nonlinearity and the structural properties of the samples

  9. Multilayered nanostructured coverings generated by a method of ion beam sputtering in vacuum

    International Nuclear Information System (INIS)

    Il'yushenko, A.F.; Andreev, M.A.; Markova, L.V.; Lisovskaya, Yu. O.

    2013-01-01

    Technological process of the formation of multilayered coverings by ion -beam sputtering is developed. At research of samples by method of AFM it is established, that the heating of a substrate leads to formation of rather large grains up to 100 nanometers in size, consisting of dispersed subgrains in the size 10-25 nanometers. The obtained results allow to say that in the course of formation of coverings interphase borders of section in one layer and section border between coat layers are formed. The use of a method of Electron Backscatter Diffraction Analysis (EBSD) has helped to confirm that the at ion-beam sputtering, ultrafine diamonds remain their diamond-like structure when migrating to the surface of the coating. It is found that with increasing number of monolayers coating microhardness increases. However, this relationship is described by a nonlinear and exponential model. (authors)

  10. Nanoscale pattern formation at surfaces under ion-beam sputtering: A perspective from continuum models

    International Nuclear Information System (INIS)

    Cuerno, Rodolfo; Castro, Mario; Munoz-Garcia, Javier; Gago, Raul; Vazquez, Luis

    2011-01-01

    Although reports on surface nanostructuring of solid targets by low to medium energy ion irradiation date back to the 1960s, only with the advent of high resolution tools for surface/interface characterization has the high potential of this procedure been recognized as a method for efficient production of surface patterns. Such morphologies are made up of periodic arrangements of nanometric sized features, like ripples and dots, with interest for technological applications due to their electronic, magnetic, and optical properties. Thus, roughly for the last ten years large efforts have been directed towards harnessing this nanofabrication technique. However, and particularly in view of recent experimental developments, we can say that the basic mechanisms controlling these pattern formation processes remain poorly understood. The lack of nanostructuring at low angles of incidence on some pure monoelemental targets, the role of impurities in the surface dynamics and other recent observations are challenging the classic view on the phenomenon as the mere interplay between the curvature dependence of the sputtering yield and surface diffusion. We review the main attempts at a theoretical (continuum) description of these systems, with emphasis on recent developments. Strong hints already exist that the nature of the morphological instability has to be rethought as originating in the material flow that is induced by the ion beam.

  11. Lead-silicate glass surface sputtered by an argon cluster ion beam investigated by XPS

    Czech Academy of Sciences Publication Activity Database

    Zemek, Josef; Jiříček, Petr; Houdková, Jana; Jurek, Karel; Gedeon, O.

    2017-01-01

    Roč. 469, Aug (2017), s. 1-6 ISSN 0022-3093 R&D Projects: GA MŠk LM2015088; GA ČR(CZ) GA15-12580S Institutional support: RVO:68378271 Keywords : lead-silicate glass * XPS * BO * NBO * Argon duster ion beam sputtering * X-ray irradiation Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.124, year: 2016

  12. Thin copper oxide films prepared by ion beam sputtering with subsequent thermal oxidation: Application in chemiresistors

    Czech Academy of Sciences Publication Activity Database

    Horák, Pavel; Bejšovec, Václav; Vacík, Jiří; Lavrentiev, Vasyl; Vrňata, M.; Kormunda, M.; Daniš, S.

    2016-01-01

    Roč. 389, DEC (2016), s. 751-759 ISSN 0169-4332 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : Copper oxide * ion beam sputtering * Van der Pauw * nuclear reaction analysis * gas sensing Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.387, year: 2016

  13. Systematic investigations of low energy Ar ion beam sputtering of Si and Ag

    Energy Technology Data Exchange (ETDEWEB)

    Feder, R., E-mail: rene.feder@iom-leipzig.de [Leibniz-Institut für Oberflächenmodifizierung, Permoserstraße 15, 04318 Leipzig (Germany); Frost, F.; Neumann, H.; Bundesmann, C.; Rauschenbach, B. [Leibniz-Institut für Oberflächenmodifizierung, Permoserstraße 15, 04318 Leipzig (Germany)

    2013-12-15

    Ion beam sputter deposition (IBD) delivers some intrinsic features influencing the growing film properties, because ion properties and geometrical process conditions generate different energy and spatial distributions of the sputtered and scattered particles. Even though IBD has been used for decades, the full capabilities are not investigated systematically and specifically used yet. Therefore, a systematic and comprehensive analysis of the correlation between the properties of the ion beam, the generated secondary particles and backscattered ions and the deposited films needs to be done. A vacuum deposition chamber has been set up which allows ion beam sputtering of different targets under variation of geometrical parameters (ion incidence angle, position of substrates and analytics in respect to the target) and of ion beam parameters (ion species, ion energy) to perform a systematic and comprehensive analysis of the correlation between the properties of the ion beam, the properties of the sputtered and scattered particles, and the properties of the deposited films. A set of samples was prepared and characterized with respect to selected film properties, such as thickness and surface topography. The experiments indicate a systematic influence of the deposition parameters on the film properties as hypothesized before. Because of this influence, the energy distribution of secondary particles was measured using an energy-selective mass spectrometer. Among others, experiments revealed a high-energetic maximum for backscattered primary ions, which shifts with increasing emission angle to higher energies. Experimental data are compared with Monte Carlo simulations done with the well-known Transport and Range of Ions in Matter, Sputtering version (TRIM.SP) code [J.P. Biersack, W. Eckstein, Appl. Phys. A: Mater. Sci. Process. 34 (1984) 73]. The thicknesses of the films are in good agreement with those calculated from simulated particle fluxes. For the positions of the

  14. Resonance ionization of sputtered atoms: Progress toward a quantitative technique

    International Nuclear Information System (INIS)

    Calaway, W.F.; Pellin, M.J.; Young, C.E.; Whitten, J.E.; Gruen, D.M.; Coon, S.R.; Texas Univ., Austin, TX; Wiens, R.C.; Burnett, D.S.; Stingeder, G.; Grasserbauer, M.

    1992-01-01

    The combination of RIMS and ion sputtering has been heralded as the ideal means of quantitatively probing the surface of a solid. While several laboratories have demonstrated the extreme sensitivity of combining RIMS with sputtering, less effort has been devoted to the question of accuracy. Using the SARISA instrument developed at Argonne National Laboratory, a number of well-characterized metallic samples have been analyzed. Results from these determinations have been compared with data obtained by several other analytical methods. One significant finding is that impurity measurements down to ppb levels in metal matrices can be made quantitative by employing polycrystalline metal foils as calibration standards. This discovery substantially reduces the effort required for quantitative analysis since a single standard can be used for determining concentrations spanning nine orders of magnitude

  15. Growth and surface morphology of ion-beam sputtered Ti-Ni thin films

    International Nuclear Information System (INIS)

    Rao, Ambati Pulla; Sunandana, C.S.

    2008-01-01

    Titanium-nickel thin films have been deposited on float glass substrates by ion beam sputtering in 100% pure argon atmosphere. Sputtering is predominant at energy region of incident ions, 1000 eV to 100 keV. The as-deposited films were investigated by X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). In this paper we attempted to study the surface morphology and elemental composition through AFM and XPS, respectively. Core level as well as valence band spectra of ion-beam sputtered Ti-Ni thin films at various Ar gas rates (5, 7 and 12 sccm) show that the thin film deposited at 3 sccm possess two distinct peaks at binding energies 458.55 eV and 464.36 eV mainly due to TiO 2 . Upon increasing Ar rate oxidation of Ti-Ni is reduced and the Ti-2p peaks begin approaching those of pure elemental Ti. Here Ti-2p peaks are observed at binding energy positions of 454.7 eV and 460.5 eV. AFM results show that the average grain size and roughness decrease, upon increasing Ar gas rate, from 2.90 μm to 0.096 μm and from 16.285 nm to 1.169 nm, respectively

  16. Stoichiometry of Silicon Dioxide Films Obtained by Ion-Beam Sputtering

    Science.gov (United States)

    Telesh, E. V.; Dostanko, A. P.; Gurevich, O. V.

    2018-03-01

    The composition of SiOx films produced by ion-beam sputtering (IBS) of silicon and quartz targets were studied by infrared spectrometry. Films with thicknesses of 150-390 nm were formed on silicon substrates. It was found that increase in the partial pressure of oxygen in the working gas, increase in the temperature of the substrate, and the presence of a positive potential on the target during reactive IBS of silicon shifted the main absorption band νas into the high-frequency region and increased the composition index from 1.41 to 1.85. During IBS of a quartz target the stoichiometry of the films deteriorates with increase of the energy of the sputtering argon ions. This may be due to increase of the deposition rate. Increase in the current of the thermionic compensator, increase of the substrate temperature, and addition of oxygen led to the formation of SiOx films with improved stoichiometry.

  17. Nanocrystalline magnetite thin films grown by dual ion-beam sputtering

    International Nuclear Information System (INIS)

    Prieto, Pilar; Ruiz, Patricia; Ferrer, Isabel J.; Figuera, Juan de la; Marco, José F.

    2015-01-01

    Highlights: • We have grown tensile and compressive strained nanocrystalline magnetite thin films by dual ion beam sputtering. • The magnetic and thermoelectric properties can be controlled by the deposition conditions. • The magnetic anisotropy depends on the crystalline grain size. • The thermoelectric properties depend on the type of strain induced in the films. • In plane uniaxial magnetic anisotropy develops in magnetite thin films with grain sizes ⩽20 nm. - Abstract: We have explored the influence of an ion-assisted beam in the thermoelectric and magnetic properties of nanocrystalline magnetite thin films grown by ion-beam sputtering. The microstructure has been investigated by XRD. Tensile and compressive strained thin films have been obtained as a function of the parameters of the ion-assisted beam. The evolution of the in-plane magnetic anisotropy was attributed to crystalline grain size. In some films, magneto-optical Kerr effect measurements reveal the existence of uniaxial magnetic anisotropy induced by the deposition process related with a small grain size (⩽20 nm). Isotropic magnetic properties have observed in nanocrystalline magnetite thin film having larger grain sizes. The largest power factor of all the films prepared (0.47 μW/K 2 cm), obtained from a Seebeck coefficient of −80 μV/K and an electrical resistivity of 13 mΩ cm, is obtained in a nanocrystalline magnetite thin film with an expanded out-of-plane lattice and with a grain size ≈30 nm

  18. Molecular dynamics and experimental studies on deposition mechanisms of ion beam sputtering

    International Nuclear Information System (INIS)

    Fang, T.-H.; Chang, W.-J.; Lin, C.-M.; Lien, W.-C.

    2008-01-01

    Molecular dynamics (MD) simulation and experimental methods are used to study the deposition mechanism of ionic beam sputtering (IBS), including the effects of incident energy, incident angle and deposition temperature on the growth process of nickel nanofilms. According to the simulation, the results showed that increasing the temperature of substrate decreases the surface roughness, average grain size and density. Increasing the incident angle increases the surface roughness and the average grain size of thin film, while decreasing its density. In addition, increasing the incident energy decreases the surface roughness and the average grain size of thin film, while increasing its density. For the cases of simulation, with the substrate temperature of 500 K, normal incident angle and 14.6 x 10 -17 J are appropriate, in order to obtain a smoother surface, a small grain size and a higher density of thin film. From the experimental results, the surface roughness of thin film deposited on the substrates of Si(1 0 0) and indium tin oxide (ITO) decreases with the increasing sputtering power, while the thickness of thin film shows an approximately linear increase with the increase of sputtering power

  19. Ion beam techniques in arts and archaeology

    International Nuclear Information System (INIS)

    Qin Guangyong; Pan Xianjia; Sun Zhongtian; Gao Zhengyao

    1991-01-01

    The ion beam techniques used in studies of arts and archaeology are compared with other analytical techniques. Some examples are specially selected to illustrate the achievements and trends of the techniques in this field

  20. Production of intensive negative lithium beam with caesium sputter-type ion source

    Science.gov (United States)

    Lobanov, Nikolai R.

    2018-01-01

    Compounds of lithium oxide, hydroxide and carbonate, mixed with silver, were prepared for use as a cathode in caesium-sputter ion source. The intention was to determine the procedure which would produce the highest intensity negative lithium beams over extended period and with maximum stability. The chemical composition and properties of the samples were analysed using mass-spectrometry, optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analyses (EDX) and Raman spectroscopy. These analyses showed that the chemical transformations with components resulted from pressing, storage and bake out were qualitatively in agreement with expectations. Intensive negative lithium ion beams >1 μA were delivered using cathodes fabricated from materials with multicomponent chemical composition when the following conditions were met: (i) use of components with moderate enthalpy of formation; (ii) low moisture content at final stage of cathode production and (iii) small concentration of water molecules in hydrate phase in the cathode mixture.

  1. Ion beam sputtered aluminum based multilayer mirrors for extreme ultraviolet solar imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ziani, A. [Laboratoire Charles Fabry, Institut d' Optique, CNRS, Univ Paris Sud, 2 Avenue Augustin Fresnel, 91127 Palaiseau cedex France (France); Centre National d’Etudes Spatiales (CNES), 18 Avenue E. Belin, 31401 Toulouse (France); Delmotte, F., E-mail: Franck.Delmotte@InstitutOptique.fr [Laboratoire Charles Fabry, Institut d' Optique, CNRS, Univ Paris Sud, 2 Avenue Augustin Fresnel, 91127 Palaiseau cedex France (France); Le Paven-Thivet, C. [Institut d' Electronique et de Télécommunications de Rennes (IETR) UMR-CNRS 6164, Université de Rennes 1, UEB, IUT Saint Brieuc, 18 rue Henri Wallon, 22004 Saint Brieuc cedex France (France); Meltchakov, E.; Jérome, A. [Laboratoire Charles Fabry, Institut d' Optique, CNRS, Univ Paris Sud, 2 Avenue Augustin Fresnel, 91127 Palaiseau cedex France (France); Roulliay, M. [Institut des Sciences Moléculaires d’Orsay UMR 8214, Univ Paris Sud, 91405 Orsay France (France); Bridou, F. [Laboratoire Charles Fabry, Institut d' Optique, CNRS, Univ Paris Sud, 2 Avenue Augustin Fresnel, 91127 Palaiseau cedex France (France); Gasc, K. [Centre National d’Etudes Spatiales (CNES), 18 Avenue E. Belin, 31401 Toulouse (France)

    2014-02-03

    In this paper, we report on the design, synthesis and characterization of extreme ultraviolet interferential mirrors for solar imaging applications in the spectral range 17 nm–34 nm. This research is carried out in the context of the preparation of the European Space Agency Solar Orbiter mission. The purpose of this study consists in optimizing the deposition of Al-based multilayers by ion beam sputtering according to several parameters such as the ion beam current and the sputtering angle. After optimization of Al thin films, several kinds of Al-based multilayer mirrors have been compared. We have deposited and characterized bi-material and also tri-material periodic multilayers: aluminum/molybdenum [Al/Mo], aluminum/molybdenum/boron carbide [Al/Mo/B{sub 4}C] and aluminum/molybdenum/silicon carbide [Al/Mo/SiC]. Best experimental results have been obtained on Al/Mo/SiC samples: we have measured reflectivity up to 48% at 17.3 nm and 27.5% at 28.2 nm on a synchrotron radiation source. - Highlights: • Design and synthesis of extreme ultraviolet interferential mirrors. • Optimization of aluminum thin films by adjusting several deposition parameters. • Comparison of results obtained with different types of Al-based multilayer mirrors. • Reflectivity up to 48% at 17.3 nm on a synchrotron radiation source.

  2. Ion beam sputtered aluminum based multilayer mirrors for extreme ultraviolet solar imaging

    International Nuclear Information System (INIS)

    Ziani, A.; Delmotte, F.; Le Paven-Thivet, C.; Meltchakov, E.; Jérome, A.; Roulliay, M.; Bridou, F.; Gasc, K.

    2014-01-01

    In this paper, we report on the design, synthesis and characterization of extreme ultraviolet interferential mirrors for solar imaging applications in the spectral range 17 nm–34 nm. This research is carried out in the context of the preparation of the European Space Agency Solar Orbiter mission. The purpose of this study consists in optimizing the deposition of Al-based multilayers by ion beam sputtering according to several parameters such as the ion beam current and the sputtering angle. After optimization of Al thin films, several kinds of Al-based multilayer mirrors have been compared. We have deposited and characterized bi-material and also tri-material periodic multilayers: aluminum/molybdenum [Al/Mo], aluminum/molybdenum/boron carbide [Al/Mo/B 4 C] and aluminum/molybdenum/silicon carbide [Al/Mo/SiC]. Best experimental results have been obtained on Al/Mo/SiC samples: we have measured reflectivity up to 48% at 17.3 nm and 27.5% at 28.2 nm on a synchrotron radiation source. - Highlights: • Design and synthesis of extreme ultraviolet interferential mirrors. • Optimization of aluminum thin films by adjusting several deposition parameters. • Comparison of results obtained with different types of Al-based multilayer mirrors. • Reflectivity up to 48% at 17.3 nm on a synchrotron radiation source

  3. Gold removal rate by ion sputtering as a function of ion-beam voltage and raster size using Auger electron spectroscopy. Final report

    International Nuclear Information System (INIS)

    Boehning, C.W.

    1983-01-01

    Gold removal rate was measured as a function of ion beam voltage and raster size using Auger electron spectroscopy (AES). Three different gold thicknesses were developed as standards. Two sputter rate calibration curves were generated by which gold sputter rate could be determined for variations in ion beam voltage or raster size

  4. Characterization of TiO2 Thin Films on Glass Substrate Growth Using DC Sputtering Technique

    International Nuclear Information System (INIS)

    Agus Santoso; Tjipto Sujitno; Sayono

    2002-01-01

    It has been fabricated and characterization a TiO 2 thin films deposited on glass substrate using DC sputtering technique. Fabrication of TiO 2 thin films were carried out at electrode voltage 4 kV, sputtering current 5 mA, vacuum pressure 5 x 10 -4 torr, deposition time 150 minutes, and temperature of the substrate were varied from 150 -350 o C, while as a gas sputter was argon. The results was tested their micro structure using SEM, and crystal structure using XRD and found that the crystal structure of TiO 2 powder before deposited on glass substrate was rutile and anatase with orientation (110) and (200) for anatase and (100) and (111) rutile structure. While the crystal structure which deposited at temperature 150 o C and deposition time 2.5 hours was anatase with orientation (001) and (200). (author)

  5. Techniques to sort Bessel beams

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2013-09-01

    Full Text Available -polar coordinate transformation, translating helically phased beams into a transverse phase gradient. By introducing two cylindrical lenses we can focus each of the azimuthal modes associated with each Bessel beam to a different lateral position in the Fourier...

  6. Stoichiometric carbon nitride synthesized by ion beam sputtering and post nitrogen ion implantation

    International Nuclear Information System (INIS)

    Valizadeh, R.; Colligon, J.S.; Katardiev, I.V.; Faunce, C.A.; Donnelly, S.E.

    1998-01-01

    Full text: Carbon nitride films have been deposited on Si (100) by ion beam sputtering a vitreous graphite target with nitrogen and argon ions with and without concurrent N2 ion bombardment at room temperature. The sputtering beam energy was 1000 eV and the assisted beam energy was 300 eV with ion / atom arrival ratio ranging from 0.5 to 5. The carbon nitride films were deposited both as single layer directly on silicon substrate and as multilayer between two layers of stoichiometric amorphous silicon nitride and polycrystalline titanium nitride. The deposited films were implanted ex-situ with 30 keV nitrogen ions with various doses ranging from 1E17 to 4E17 ions.cm -2 and 2 GeV xenon ion with a dose of 1E12 ions.cm -2 . The nitrogen concentration of the films was measured with Rutherford Backscattering (RBS), Secondary Neutral Mass Spectrometry (SNMS) and Parallel Electron Energy Loss Spectroscopy (PEELS). The nitrogen concentration for as deposited sample was 34 at% and stoichiometric carbon nitride C 3 N 4 was achieved by post nitrogen implantation of the multi-layered films. Post bombardment of single layer carbon nitride films lead to reduction in the total nitrogen concentration. Carbon K edge structure obtained from PEELS analysis suggested that the amorphous C 3 N 4 matrix was predominantly sp 2 bonded. This was confirmed by Fourier Transforrn Infra-Red Spectroscopy (FTIR) analysis of the single CN layer which showed the nitrogen was mostly bonded with carbon in nitrile (C≡N) and imine (C=N) groups. The microstructure of the film was determined by Transmission Electron Microscopy (TEM) which indicated that the films were amorphous

  7. Structural and corrosion characterization of hydroxyapatite/zirconium nitride-coated AZ91 magnesium alloy by ion beam sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Kiahosseini, Seyed Rahim, E-mail: rkiahoseyni@yahoo.com [Young Researchers and Elite Club, Damghan Branch, Islamic Azad University, Damghan (Iran, Islamic Republic of); Afshar, Abdollah [Department of Material Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Mojtahedzadeh Larijani, Majid [Radiation Applications Research School, Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Yousefpour, Mardali [Faculty of Materials and Metallurgical Engineering, Semnan University, Semnan, 35131-19111 (Iran, Islamic Republic of)

    2017-04-15

    Highlights: • The thickness of HA coatings increase by ion beam sputtering time. • The residual strain in HA structure decrease by deposition time increment. • Crystallite size of HA coatings increase by deposition time increment. • The best corrosion resistance occurs at intermediate deposition time. - Abstract: The adhesion of hydroxyapatite (HA) as a coating for the AZ91 magnesium alloy substrate can be improved by using the sputtering method and an intermediate layer, such as ZrN. In this study, HA coatings were applied on ZrN intermediate layers at a temperature of 300 °C for 180, 240, 300, 360, and 420 min by ion beam sputtering. A profilometer device was used to study the HA coating thickness, which changed from 2 μm for the 180-min deposition to 4.7 μm for 420-min deposition. The grazing incidence X-ray diffraction analysis method and the Williamson–Hall analysis were used for structural investigation. As the deposition time increased, the crystalline size increased from 50 nm to 690 nm. However, given sufficient time for stress relief on the coating structure, the lattice strain values were close to zero. Energy-dispersive X-ray spectroscopy results showed that the Ca/P ratio ranged from 1.73 to 1.81. The external indentation method was used to evaluate the coating adhesion to the substrate. The slope of curve for applied force changes versus the radius of cracks in the coating (dP/dr) varied in the range of 0.2–0.07 by the deposition time, indicating that the adhesion increased with the increase in coating thickness. The potentiodynamic polarization technique was used to study the corrosion behavior. With increasing deposition time, the corrosion potential of samples did not show a significant change, and the corrosion potential of all samples (coated and uncoated substrates) was more positive than approximately 55 mV. When the deposition time increased to 360 min, the corrosion current density decreased from 5.5 μA/cm{sup 2} to 0.33

  8. Titanium dioxide fine structures by RF magnetron sputter method deposited on an electron-beam resist mask

    Science.gov (United States)

    Hashiba, Hideomi; Miyazaki, Yuta; Matsushita, Sachiko

    2013-09-01

    Titanium dioxide (TiO2) has been draw attention for wide range of applications from photonic crystals for visible light range by its catalytic characteristics to tera-hertz range by its high refractive index. We present an experimental study of fabrication of fine structures of TiO2 with a ZEP electron beam resist mask followed by Ti sputter deposition techniques. A TiO2 thin layer of 150 nm thick was grown on an FTO glass substrate with a fine patterned ZEP resist mask by a conventional RF magnetron sputter method with Ti target. The deposition was carried out with argon-oxygen gases at a pressure of 5.0 x 10 -1 Pa in a chamber. During the deposition, ratio of Ar-O2 gas was kept to the ratio of 2:1 and the deposition ratio was around 0.5 Å/s to ensure enough oxygen to form TiO2 and low temperature to avoid deformation of fine pattern of the ZPU resist mask. Deposited TiO2 layers are white-transparent, amorphous, and those roughnesses are around 7 nm. Fabricated TiO2 PCs have wider TiO2 slabs of 112 nm width leaving periodic 410 x 410 nm2 air gaps. We also studied transformation of TiO2 layers and TiO2 fine structures by baking at 500 °C. XRD measurement for TiO2 shows that the amorphous TiO2 transforms to rutile and anatase forms by the baking while keeping the same profile of the fine structures. Our fabrication method can be one of a promising technique to optic devices on researches and industrial area.

  9. Control of surface ripple amplitude in ion beam sputtered polycrystalline cobalt films

    Energy Technology Data Exchange (ETDEWEB)

    Colino, Jose M., E-mail: josemiguel.colino@uclm.es [Institute of Nanoscience, Nanotechnology and Molecular Materials, University of Castilla-La Mancha, Campus de la Fabrica de Armas, Toledo 45071 (Spain); Arranz, Miguel A. [Facultad de Ciencias Quimicas, University of Castilla-La Mancha, Ciudad Real 13071 (Spain)

    2011-02-15

    We have grown both polycrystalline and partially textured cobalt films by magnetron sputter deposition in the range of thickness (50-200 nm). Kinetic roughening of the growing film leads to a controlled rms surface roughness values (1-6 nm) increasing with the as-grown film thickness. Ion erosion of a low energy 1 keV Ar+ beam at glancing incidence (80{sup o}) on the cobalt film changes the surface morphology to a ripple pattern of nanometric wavelength. The wavelength evolution at relatively low fluency is strongly dependent on the initial surface topography (a wavelength selection mechanism hereby confirmed in polycrystalline rough surfaces and based on the shadowing instability). At sufficiently large fluency, the ripple wavelength steadily increases on a coarsening regime and does not recall the virgin surface morphology. Remarkably, the use of a rough virgin surface makes the ripple amplitude in the final pattern can be controllably increased without affecting the ripple wavelength.

  10. Optical and tribomechanical stability of optically variable interference security devices prepared by dual ion beam sputtering.

    Science.gov (United States)

    Çetinörgü-Goldenberg, Eda; Baloukas, Bill; Zabeida, Oleg; Klemberg-Sapieha, Jolanta; Martinu, Ludvik

    2011-07-01

    Optical security devices applied to banknotes and other documents are exposed to different types of harsh environments involving the cycling of temperature, humidity, chemical agents, and tribomechanical intrusion. In the present work, we study the stability of optically variable devices, namely metameric interference filters, prepared by dual ion beam sputtering onto polycarbonate and glass substrates. Specifically, we assess the color difference as well as the changes in the mechanical properties and integrity of all-dielectric and metal-dielectric systems due to exposure to bleach, detergent and acetone agents, and heat and humidity. The results underline a significant role of the substrate material, of the interfaces, and of the nature and microstructure of the deposited films in long term stability under everyday application conditions.

  11. Preparation and comparison of a-C:H coatings using reactive sputter techniques

    Energy Technology Data Exchange (ETDEWEB)

    Keunecke, M., E-mail: martin.keunecke@ist.fraunhofer.d [Fraunhofer Institute for Surface Engineering and Thin Films (IST), Braunschweig (Germany); Weigel, K.; Bewilogua, K. [Fraunhofer Institute for Surface Engineering and Thin Films (IST), Braunschweig (Germany); Cremer, R.; Fuss, H.-G. [CemeCon AG, Wuerselen (Germany)

    2009-12-31

    Amorphous hydrogenated carbon (a-C:H) coatings are widely used in several industrial applications. These coatings commonly will be prepared by plasma activated chemical vapor deposition (PACVD). The main method used to prepare a-C:H coating in industrial scale is based on a glow discharge in a hydrocarbon gas like acetylene or methane using a substrate electrode powered with medium frequency (m.f. - some 10 to 300 kHz). Some aims of further development are adhesion improvement, increase of hardness and high coating quality on complex geometries. A relatively new and promising technique to fulfil these requirements is the deposition of a-C:H coatings by a reactive d.c. magnetron sputter deposition from a graphite target with acetylene as reactive gas. An advancement of this technique is the deposition in a pulsed magnetron sputter process. Using these three mentioned techniques a-C:H coatings were prepared in the same deposition machine. For adhesion improvement different interlayer systems were applied. The effect of different substrate bias voltages (d.c. and d.c. pulse) was investigated. By applying the magnetron sputter technique in the d.c. pulse mode, plastic hardness values up to 40 GPa could be reached. Besides hardness other mechanical properties like resistance against abrasive wear were measured and compared. Cross sectional SEM images showed the growth structure of the coatings.

  12. The rf-power dependences of the deposition rate, the hardness and the corrosion-resistance of the chromium nitride film deposited by using a dual ion beam sputtering system

    International Nuclear Information System (INIS)

    Lim, Jongmin; Lee, Chongmu

    2006-01-01

    The hexavalent chromium used in chromium plating is so toxic that it is very hazardous to human body and possibly causes cancer in humans. Therefore, it is indispensable to develop an alternative deposition technique. Dependences of the deposition rate, the phases, the hardness, the surface roughness and the corrosion-resistance of CrN x deposited on the high speed steel substrate by using a dual ion beam sputtering system on the rf-power were investigated to see the feasibility of sputtering as an alternative technique for chromium plating. The dual ion beam sputtering system used in this study was designed in such a way as the primary argon ion beam and the secondary nitrogen ion beam are injected toward the target and the substrate, respectively so that the chromium atoms at the chromium target surface may not nearly react with nitrogen atoms. The hardness and the surface roughness were measured by a micro-Vicker's hardness tester and an atomic force microscope (AFM), respectively. X-ray diffraction analyses were performed to identify phases in the films. The deposition rate of CrN x depends more strongly upon the rf-power for argon ion beam than that for nitrogen ion beam. The hardness of the CrN x film is highest when the volume percent of the Cr 2 N phase in the film is highest. Amorphous films are obtained when the rf-power for nitrogen ion beam is much higher than that for argon ion beam. The CrN x film deposited by using the sputtering technique under the optimal condition provides corrosion-resistance comparable to that of the electroplated chromium

  13. 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

  14. Laser sputter neutral mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    King, B V; Clarke, M; Hu, H; Betz, [Newcastle Univ., NSW (Australia). Dept. of Physics

    1994-12-31

    Laser sputter neutral mass spectrometry (LSNMS) is an emerging technique for highly sensitive surface analysis. In this technique a target is bombarded with a pulsed beam of keV ions. The sputtered particles are intercepted by a high intensity pulsed laser beam above the surface and ionised with almost 100% efficiency. The photions may then be mass analysed using a quadrupole or, more commonly, using time of flight (TOF) techniques. In this method photoions are extracted from the ionisation region, accelerated to a known energy E{sub o} and strike a channelplate detector a distance `d` away. The flight time `t` of the photoions is then related to their mass by `d` {radical}m / {radical} 2E{sub o} so measurement of `t` allows mass spectra to be obtained. It is found that LSNMS is an emerging technique of great sensitivity and flexibility, useful for both applied analysis and to investigate basic sputtering processes. 4 refs., 3 figs.

  15. Laser sputter neutral mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    King, B.V.; Clarke, M.; Hu, H.; Betz [Newcastle Univ., NSW (Australia). Dept. of Physics

    1993-12-31

    Laser sputter neutral mass spectrometry (LSNMS) is an emerging technique for highly sensitive surface analysis. In this technique a target is bombarded with a pulsed beam of keV ions. The sputtered particles are intercepted by a high intensity pulsed laser beam above the surface and ionised with almost 100% efficiency. The photions may then be mass analysed using a quadrupole or, more commonly, using time of flight (TOF) techniques. In this method photoions are extracted from the ionisation region, accelerated to a known energy E{sub o} and strike a channelplate detector a distance `d` away. The flight time `t` of the photoions is then related to their mass by `d` {radical}m / {radical} 2E{sub o} so measurement of `t` allows mass spectra to be obtained. It is found that LSNMS is an emerging technique of great sensitivity and flexibility, useful for both applied analysis and to investigate basic sputtering processes. 4 refs., 3 figs.

  16. Zn Thin Film Deposition for Fe Layer Shielding Use the Sputtering Technique on Cylindrical Form

    International Nuclear Information System (INIS)

    Yunanto; Tjipto Sujitno, BA; Suprapto; Simbolon, Sahat

    2002-01-01

    Deposition of thin film on Fe substrate use sputtering technique on cylindrical form was carried out. The purpose of this research is to protect Fe due to the corrosion with Zn thin film. Sputtering method was proposed to protect a component of complex form. Substrate has functioned as anode, meanwhile target in cylindrical form as a cathode. Argon ion from anode bombard Zn with enough energy for releasing Zn. Zn atom would scatter and some of then was focused on the anode. For testing Zn atom on Fe by using XRF and corrosion rate with potentiostat. It was found that corrosion rate was decreased from 0.051 mpy to 0.031 mpy on 0.63 % of Fe substrate. (author)

  17. Energy dependence of angular distributions of sputtered particles by ion-beam bombardment at normal incidence

    International Nuclear Information System (INIS)

    Matsuda, Yoshinobu; Ueda, Yasutoshi; Uchino, Kiichiro; Muraoka, Katsunori; Maeda, Mitsuo; Akazaki, Masanori; Yamamura, Yasunori.

    1986-01-01

    The angular distributions of sputtered Fe-atoms were measured using the laser fluorescence technique during Ar-ion bombardment for energies of 0.6, 1, 2 and 3 keV at normal incidence. The measured cosine distribution at 0.6 keV progressively deviated to an over-cosine distribution at higher energies, and at 3 keV the angular distribution was an overcosine distribution of about 20 %. The experimental results agree qualitatively with calculations by a recent computer simulation code, ACAT. The results are explained by the competition between surface scattering and the effects of primary knock-on atoms, which tend to make the angular distributions over-cosine and under-cosine, respectively. (author)

  18. Experience with Kicker Beam Coupling Reduction Techniques

    CERN Document Server

    Gaxiola, Enrique; Caspers, Friedhelm; Ducimetière, Laurent; Kroyer, Tom

    2005-01-01

    SPS beam impedance is still one of the worries for operation with nominal LHC beam over longer periods, once the final configuration will be installed in 2006. Several CERN SPS kickers suffer from significant beam induced ferrite heating. In specific cases, for instance beam scrubbing, the temperature of certain ferrite yokes went beyond the Curie point. Several retrofit impedance reduction techniques have been investigated theoretically and with practical tests. We report on experience gained during the 2004 SPS operation with resistively coated ceramic inserts in terms of kicker heating, pulse rise time, operating voltage, and vacuum behaviour. For another technique using interleaved metallic stripes we observed significant improvements in bench measurements. Advantages and drawbacks of both methods and potential combinations of them are discussed and simulation as well as measured data are shown. Prospects for further improvements beyond 2006 are briefly outlined.

  19. 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.

  20. Fabrication of highly oriented β-FeSi2 by ion beam sputter deposition

    International Nuclear Information System (INIS)

    Nakanoya, Takamitsu; Sasase, Masato; Yamamoto, Hiroyuki; Saito, Takeru; Hojou, Kiichi

    2002-01-01

    We have prepared the 'environmentally friendly' semiconductor, β-FeSi 2 thin films by ion beam sputter deposition method. The temperature of Si (100) substrate during the deposition and total amount of deposited Fe have been changed in order to find the optimum condition of the film formation. The crystallinity and surface morphology of the formed silicides were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. It is understood that the domain of the epitaxially grown β-FeSi 2 increases with the substrate temperature up to 700degC at the fixed amount of deposited Fe (33 nm) by XRD spectra. On the other hand, α-FeSi 2 is appeared and increased with the temperature above 700degC. Granulation of the surface is also observed by SEM images at this temperature region. At the fixed temperature condition (700degC), formation of α phase, which is obtained at the higher temperature compared with β phase, is observed for the fewer deposited samples. These results suggest the possibility of the epitaxially grown β-FeSi 2 formation at the lower (< 700degC) temperature region. (author)

  1. ZrN coatings deposited by high power impulse magnetron sputtering and cathodic arc techniques

    Energy Technology Data Exchange (ETDEWEB)

    Purandare, Yashodhan, E-mail: Y.Purandare@shu.ac.uk; Ehiasarian, Arutiun; Hovsepian, Papken [Nanotechnology Centre for PVD Research, Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom); Santana, Antonio [Ionbond AG Olten, Industriestrasse 211, CH-4600 Olten (Switzerland)

    2014-05-15

    Zirconium nitride (ZrN) coatings were deposited on 1 μm finish high speed steel and 316L stainless steel test coupons. Cathodic Arc (CA) and High Power Impulse Magnetron Sputtering (HIPIMS) + Unbalanced Magnetron Sputtering (UBM) techniques were utilized to deposit coatings. CA plasmas are known to be rich in metal and gas ions of the depositing species as well as macroparticles (droplets) emitted from the arc sports. Combining HIPIMS technique with UBM in the same deposition process facilitated increased ion bombardment on the depositing species during coating growth maintaining high deposition rate. Prior to coating deposition, substrates were pretreated with Zr{sup +} rich plasma, for both arc deposited and HIPIMS deposited coatings, which led to a very high scratch adhesion value (L{sub C2}) of 100 N. Characterization results revealed the overall thickness of the coatings in the range of 2.5 μm with hardness in the range of 30–40 GPa depending on the deposition technique. Cross-sectional transmission electron microscopy and tribological experiments such as dry sliding wear tests and corrosion studies have been utilized to study the effects of ion bombardment on the structure and properties of these coatings. In all the cases, HIPIMS assisted UBM deposited coating fared equal or better than the arc deposited coatings, the reasons being discussed in this paper. Thus H+U coatings provide a good alternative to arc deposited where smooth, dense coatings are required and macrodroplets cannot be tolerated.

  2. Fabrication of hydroxyapatite thin films on polyetheretherketone substrates using a sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, K., E-mail: kazuhide.ozeki.365@vc.ibaraki.ac.jp [Department of Mechanical Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Masuzawa, T. [Department of Mechanical Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Aoki, H. [International Apatite Institute Co., Ltd., 2-12-9, Misaki-cho, Chiyoda-ku, Tokyo 101-0061 (Japan)

    2017-03-01

    Hydroxyapatite (HA) thin films were coated on a polyetheretherketone (PEEK) substrate using a sputtering technique. A thin titanium (Ti) intermediate layer was formed between the HA and the PEEK surface to improve adhesion of the HA film to the PEEK substrate. The coated films were recrystallized using a hydrothermal treatment to reduce the dissolution of the HA film. The films were then characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and a UV-Vis spectrophotometer. A pull-out test was performed to measure the film-to-substrate adhesion strength, and an immersion test was performed in ultra-pure water. In the XRD patterns of the sputtered film with the Ti intermediate layer on the PEEK substrate, small HA peaks and large Ti peaks were observed. After the hydrothermal treatment, the intensity of the HA peaks increased. The transmittance of the HA films with 5 and 10 nm Ti intermediate layers was > 79% and 68%, respectively, in the visible light wavelength region (400–700 nm) after the hydrothermal treatment. The adhesion strength of the hydrothermally treated HA films increased with decreasing thickness of the Ti intermediate layer, and the strength reached 2.7 MPa with the 5-nm-thick Ti intermediate layer. In the immersion test, the HA film with a 5-nm-thick Ti intermediate layer without hydrothermal treatment exhibited a released Ti concentration of 42.0 ± 2.4 ppb. After hydrothermal treatment, the released Ti concentration decreased to 17.3 ± 1.1 ppb. - Highlights: • Hydroxyapatite (HA) thin films were coated on a polyetheretherketone (PEEK) substrate using a sputtering technique. • A thin Ti intermediate layer was formed between the HA and the PEEK surface to improve adhesion of the HA film. • The adhesion strength of the HA films with the Ti intermediate layer increased with decreasing thickness of the Ti layer.

  3. Fabrication of hydroxyapatite thin films on polyetheretherketone substrates using a sputtering technique

    International Nuclear Information System (INIS)

    Ozeki, K.; Masuzawa, T.; Aoki, H.

    2017-01-01

    Hydroxyapatite (HA) thin films were coated on a polyetheretherketone (PEEK) substrate using a sputtering technique. A thin titanium (Ti) intermediate layer was formed between the HA and the PEEK surface to improve adhesion of the HA film to the PEEK substrate. The coated films were recrystallized using a hydrothermal treatment to reduce the dissolution of the HA film. The films were then characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and a UV-Vis spectrophotometer. A pull-out test was performed to measure the film-to-substrate adhesion strength, and an immersion test was performed in ultra-pure water. In the XRD patterns of the sputtered film with the Ti intermediate layer on the PEEK substrate, small HA peaks and large Ti peaks were observed. After the hydrothermal treatment, the intensity of the HA peaks increased. The transmittance of the HA films with 5 and 10 nm Ti intermediate layers was > 79% and 68%, respectively, in the visible light wavelength region (400–700 nm) after the hydrothermal treatment. The adhesion strength of the hydrothermally treated HA films increased with decreasing thickness of the Ti intermediate layer, and the strength reached 2.7 MPa with the 5-nm-thick Ti intermediate layer. In the immersion test, the HA film with a 5-nm-thick Ti intermediate layer without hydrothermal treatment exhibited a released Ti concentration of 42.0 ± 2.4 ppb. After hydrothermal treatment, the released Ti concentration decreased to 17.3 ± 1.1 ppb. - Highlights: • Hydroxyapatite (HA) thin films were coated on a polyetheretherketone (PEEK) substrate using a sputtering technique. • A thin Ti intermediate layer was formed between the HA and the PEEK surface to improve adhesion of the HA film. • The adhesion strength of the HA films with the Ti intermediate layer increased with decreasing thickness of the Ti layer.

  4. Laser damage resistance of hafnia thin films deposited by electron beam deposition, reactive low voltage ion plating, and dual ion beam sputtering

    International Nuclear Information System (INIS)

    Gallais, Laurent; Capoulade, Jeremie; Natoli, Jean-Yves; Commandre, Mireille; Cathelinaud, Michel; Koc, Cian; Lequime, Michel

    2008-01-01

    A comparative study is made of the laser damage resistance of hafnia coatings deposited on fused silica substrates with different technologies: electron beam deposition (from Hf or HfO2 starting material), reactive low voltage ion plating, and dual ion beam sputtering.The laser damage thresholds of these coatings are determined at 1064 and 355 nm using a nanosecond pulsed YAG laser and a one-on-one test procedure. The results are associated with a complete characterization of the samples: refractive index n measured by spectrophotometry, extinction coefficient k measured by photothermal deflection, and roughness measured by atomic force microscopy

  5. Techniques for beam impedance measurements above cutoff

    International Nuclear Information System (INIS)

    Lambertson, G.R.; Jacob, A.F.; Rimmer, R.A.; Voelker, F.

    1990-08-01

    Methods for measuring beam impedance above cutoff have been very limited. For design work on the ALS we have developed two techniques that yield data in the frequency domain with high sensitivity. The first is an extension of the wire method; the second utilizes traveling TM waves to simulate the beam's fields at the wall, and thus avoids the mechanical difficulties of mounting the wire. It is also more sensitive than the other method but the interpretation is complicated by the presence of higher order modes. With either method we were able to detect resonant peaks smaller than 1 Ohm at 10 GHz

  6. Angular Distributions of Sputtered Atoms from Semiconductor Targets at Grazing Ion Beam Incidence Angles

    International Nuclear Information System (INIS)

    Sekowski, M.; Burenkov, A.; Martinez-Limia, A.; Hernandez-Mangas, J.; Ryssel, H.

    2008-01-01

    Angular distributions of ion sputtered germanium and silicon atoms are investigated within this work. Experiments are performed for the case of grazing ion incidence angles, where the resulting angular distributions are asymmetrical with respect to the polar angle of the sputtered atoms. The performed experiments are compared to Monte-Carlo simulations from different programs. We show here an improved model for the angular distribution, which has an additional dependence of the ion incidence angle.

  7. Compensation techniques in NIRS proton beam radiotherapy

    International Nuclear Information System (INIS)

    Akanuma, A.; Majima, H.; Furukawa, S.

    1982-01-01

    Proton beam has the dose distribution advantage in radiation therapy, although it has little advantage in biological effects. One of the best advantages is its sharp fall off of dose after the peak. With proton beam, therefore, the dose can be given just to cover a target volume and potentially no dose is delivered thereafter in the beam direction. To utilize this advantage, bolus techniques in conjunction with CT scanning are employed in NIRS proton beam radiation therapy planning. A patient receives CT scanning first so that the target volume can be clearly marked and the radiation direction and fixation method can be determined. At the same time bolus dimensions are calculated. The bolus frames are made with dental paraffin sheets according to the dimensions. The paraffin frame is replaced with dental resin. Alginate (a dental impression material with favorable physical density and skin surface contact) is now employed for the bolus material. With fixation device and bolus on, which are constructed individually, the patient receives CT scanning again prior to a proton beam treatment in order to prove the devices are suitable. Alginate has to be poured into the frame right before each treatments. Further investigations are required to find better bolus materials and easier construction methods

  8. Compensation techniques in NIRS proton beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Akanuma, A. (Univ. of Tokyo, Japan); Majima, H.; Furukawa, S.

    1982-09-01

    Proton beam has the dose distribution advantage in radiation therapy, although it has little advantage in biological effects. One of the best advantages is its sharp fall off of dose after the peak. With proton beam, therefore, the dose can be given just to cover a target volume and potentially no dose is delivered thereafter in the beam direction. To utilize this advantage, bolus techniques in conjunction with CT scanning are employed in NIRS proton beam radiation therapy planning. A patient receives CT scanning first so that the target volume can be clearly marked and the radiation direction and fixation method can be determined. At the same time bolus dimensions are calculated. The bolus frames are made with dental paraffin sheets according to the dimensions. The paraffin frame is replaced with dental resin. Alginate (a dental impression material with favorable physical density and skin surface contact) is now employed for the bolus material. With fixation device and bolus on, which are constructed individually, the patient receives CT scanning again prior to a proton beam treatment in order to prove the devices are suitable. Alginate has to be poured into the frame right before each treatments. Further investigations are required to find better bolus materials and easier construction methods.

  9. Electron beam instrumentation techniques using coherent radiation

    International Nuclear Information System (INIS)

    Wang, D.X.

    1997-01-01

    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

  10. Novel magnetic controlled plasma sputtering method

    International Nuclear Information System (INIS)

    Axelevich, A.; Rabinovich, E.; Golan, G.

    1996-01-01

    A novel method to improve thin film vacuum sputtering is presented. This method is capable of controlling the sputtering plasma via an external set of magnets, in a similar fashion to the tetrode sputtering method. The main advantage of the Magnetic Controlled Plasma Sputtering (MCPS) is its ability to independently control all deposition parameters without any interference or cross-talk. Deposition rate, using the MCPS, is found to be almost twice the rate of triode and tetrode sputtering techniques. Experimental results using the MCPS to deposit Ni layers are described. It was demonstrated that using the MCPS method the ion beam intensity at the target is a result of the interaction of a homogeneous external magnetic field and the controlling magnetic fields. The MCPS method was therefore found to be beneficial for the production of pure stoichiometric thin solid films with high reproducibility. This method could be used for the production of compound thin films as well. (authors)

  11. Nickel oxide films by thermal annealing of ion-beam-sputtered Ni: Structure and electro-optical properties

    Czech Academy of Sciences Publication Activity Database

    Horák, Pavel; Remeš, Zdeněk; Bejšovec, Václav; Vacík, Jiří; Daniš, S.; Kormunda, M.

    2017-01-01

    Roč. 640, č. 10 (2017), s. 52-59 ISSN 0040-6090 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA ČR(CZ) GA14-05053S; GA MŠk LM2015056 Institutional support: RVO:61389005 ; RVO:68378271 Keywords : NiO * ion beam sputtering * thermal annealing * nuclear analytical methods * optical properties Subject RIV: JK - Corrosion ; Surface Treatment of Materials; BM - Solid Matter Physics ; Magnetism (FZU-D) OBOR OECD: Coating and films; Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D) Impact factor: 1.879, year: 2016

  12. Effect of Annealing Temperature and Oxygen Flow in the Properties of Ion Beam Sputtered SnO-₂x Thin Films.

    Science.gov (United States)

    Wang, Chun-Min; Huang, Chun-Chieh; Kuo, Jui-Chao; Sahu, Dipti Ranjan; Huang, Jow-Lay

    2015-08-14

    Tin oxide (SnO 2-x ) thin films were prepared under various flow ratios of O₂/(O₂ + Ar) on unheated glass substrate using the ion beam sputtering (IBS) deposition technique. This work studied the effects of the flow ratio of O₂/(O₂ + Ar), chamber pressures and post-annealing treatment on the physical properties of SnO₂ thin films. It was found that annealing affects the crystal quality of the films as seen from both X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis. In addition, the surface RMS roughness was measured with atomic force microscopy (AFM). Auger electron spectroscopy (AES) analysis was used to obtain the changes of elemental distribution between tin and oxygen atomic concentration. The electrical property is discussed with attention to the structure factor.

  13. Effect of Annealing Temperature and Oxygen Flow in the Properties of Ion Beam Sputtered SnO—2x Thin Films

    Directory of Open Access Journals (Sweden)

    Chun-Min Wang

    2015-08-01

    Full Text Available Tin oxide (SnO2—x thin films were prepared under various flow ratios of O2/(O2 + Ar on unheated glass substrate using the ion beam sputtering (IBS deposition technique. This work studied the effects of the flow ratio of O2/(O2 + Ar, chamber pressures and post-annealing treatment on the physical properties of SnO2 thin films. It was found that annealing affects the crystal quality of the films as seen from both X-ray diffraction (XRD and transmission electron microscopy (TEM analysis. In addition, the surface RMS roughness was measured with atomic force microscopy (AFM. Auger electron spectroscopy (AES analysis was used to obtain the changes of elemental distribution between tin and oxygen atomic concentration. The electrical property is discussed with attention to the structure factor.

  14. Thin copper oxide films prepared by ion beam sputtering with subsequent thermal oxidation: Application in chemiresistors

    Science.gov (United States)

    Horak, P.; Bejsovec, V.; Vacik, J.; Lavrentiev, V.; Vrnata, M.; Kormunda, M.; Danis, S.

    2016-12-01

    Copper oxide films were prepared by thermal oxidation of thin Cu films deposited on substrates by ion beam sputtering. The subsequent oxidation was achieved in the temperature range of 200 °C-600 °C with time of treatment from 1 to 7 h (with a 1-h step) in a furnace open to air. At temperatures 250 °C-600 °C, the dominant phase formed was CuO, while at 200 °C mainly the Cu2O phase was identified. However, the oxidation at 200 °C led to a more complicated composition - in the depth Cu2O phase was observed, though in the near-surface layer the CuO dominant phase was found with a significant presence of Cu(OH)2. A limited amount of Cu2O was also found in samples annealed at 600 °C. The sheet resistance RS of the as-deposited Cu sample was 2.22 Ω/□, after gradual annealing RS was measured in the range 2.64 MΩ/□-2.45 GΩ/□. The highest RS values were obtained after annealing at 300 °C and 350 °C, respectively. Oxygen depth distribution was studied using the 16O(α,α) nuclear reaction with the resonance at energy 3032 keV. It was confirmed that the higher oxidation degree of copper is located in the near-surface region. Preliminary tests of the copper oxide films as an active layer of a chemiresistor were also performed. Hydrogen and methanol vapours, with a concentration of 1000 ppm, were detected by the sensor at an operating temperature of 300 °C and 350 °C, respectively. The response of the sensors, pointed at the p-type conductivity, was improved by the addition of thin Pd or Au catalytic films to the oxidic film surface. Pd-covered films showed an increased response to hydrogen at 300 °C, while Au-covered films were more sensitive to methanol vapours at 350 °C.

  15. Thin copper oxide films prepared by ion beam sputtering with subsequent thermal oxidation: Application in chemiresistors

    Energy Technology Data Exchange (ETDEWEB)

    Horak, P., E-mail: phorak@ujf.cas.cz [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, 250 68 Řež (Czech Republic); Bejsovec, V.; Vacik, J.; Lavrentiev, V. [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, 250 68 Řež (Czech Republic); Vrnata, M. [Department of Physics and Measurements, The University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6 (Czech Republic); Kormunda, M. [Department of Physics, Jan Evangelista Purkyně University in Ústí nad Labem, České mládeže 8, 400 96 Ústí nad Labem (Czech Republic); Danis, S. [Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic)

    2016-12-15

    Highlights: • A rapid oxidation process of thin copper films. • Sheet resistance up to 10{sup 9} Ω/◊. • Mixed oxide phase at 200 °C with significant hydroxide presence. • Gas sensing response to 1000 ppm of hydrogen and methanol vapours. • Increased sensitivity with Pd and Au catalyst to hydrogen and methanol, respectively. - Abstract: Copper oxide films were prepared by thermal oxidation of thin Cu films deposited on substrates by ion beam sputtering. The subsequent oxidation was achieved in the temperature range of 200 °C–600 °C with time of treatment from 1 to 7 h (with a 1-h step) in a furnace open to air. At temperatures 250 °C–600 °C, the dominant phase formed was CuO, while at 200 °C mainly the Cu{sub 2}O phase was identified. However, the oxidation at 200 °C led to a more complicated composition − in the depth Cu{sub 2}O phase was observed, though in the near-surface layer the CuO dominant phase was found with a significant presence of Cu(OH){sub 2}. A limited amount of Cu{sub 2}O was also found in samples annealed at 600 °C. The sheet resistance R{sub S} of the as-deposited Cu sample was 2.22 Ω/□, after gradual annealing R{sub S} was measured in the range 2.64 MΩ/□–2.45 GΩ/□. The highest R{sub S} values were obtained after annealing at 300 °C and 350 °C, respectively. Oxygen depth distribution was studied using the {sup 16}O(α,α) nuclear reaction with the resonance at energy 3032 keV. It was confirmed that the higher oxidation degree of copper is located in the near-surface region. Preliminary tests of the copper oxide films as an active layer of a chemiresistor were also performed. Hydrogen and methanol vapours, with a concentration of 1000 ppm, were detected by the sensor at an operating temperature of 300 °C and 350 °C, respectively. The response of the sensors, pointed at the p-type conductivity, was improved by the addition of thin Pd or Au catalytic films to the oxidic film surface. Pd-covered films showed

  16. Sputtering of carbon using hydrogen ion beams with energies of 60–800 eV

    Energy Technology Data Exchange (ETDEWEB)

    Sidorov, Dmitry S., E-mail: dmitrisidoroff@rambler.ru [Nizhny Novgorod State University, 23 Gagarina Avenue, Nizhny Novgorod, Nizhny Novgorod Region 603950 (Russian Federation); Chkhalo, Nikolay I., E-mail: chkhalo@ipm.sci-nnov.ru [Institute for Physics of Microstructures RAS, Academicheskaya Str. 7, Afonino, Nizhny Novgorod Region, Kstovsky District, Kstovo Region 603087 (Russian Federation); Mikhailenko, Mikhail S.; Pestov, Alexey E.; Polkovnikov, Vladimir N. [Institute for Physics of Microstructures RAS, Academicheskaya Str. 7, Afonino, Nizhny Novgorod Region, Kstovsky District, Kstovo Region 603087 (Russian Federation)

    2016-11-15

    This article presents the result of a study on the sputtering of carbon films by low-energy hydrogen ions. In particular, the etching rate and surface roughness were measured. The range of energies where the sputtering switches from pure chemical to a combination of chemical and physical mechanisms was determined. It is shown that Sigmund’s theory for ion etching does not work well for fields of energy less than 150 eV and that it accurately describes the dependence of a sputtering coefficient on ion energy for energies greater than 300 eV. A strong smoothing effect for the surface of carbon film was also found. This result is interesting in itself and for its significance for the manufacture of super-smooth surfaces for X-ray applications.

  17. Determining the sputter yields of molybdenum in low-index crystal planes via electron backscattered diffraction, focused ion beam and atomic force microscope

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.S., E-mail: 160184@mail.csc.com.tw [New Materials Research and Development Department, China Steel Corporation, 1 Chung Kang Road, Hsiao Kang, Kaohsiung 812, Taiwan, ROC (China); Chiu, C.H.; Hong, I.T.; Tung, H.C. [New Materials Research and Development Department, China Steel Corporation, 1 Chung Kang Road, Hsiao Kang, Kaohsiung 812, Taiwan, ROC (China); Chien, F.S.-S. [Department of Physics, Tunghai University, 1727, Sec. 4, Xitun Dist., Taiwan Boulevard, Taichung 407, Taiwan, ROC (China)

    2013-09-15

    Previous literature has used several monocrystalline sputtering targets with various crystalline planes, respectively, to investigate the variations of the sputter yield of materials in different crystalline orientations. This study presents a method to measure the sputtered yields of Mo for the three low-index planes (100), (110), and (111), through using an easily made polycrystalline target. The procedure was firstly to use electron backscattered diffraction to identify the grain positions of the three crystalline planes, and then use a focused ion beam to perform the micro-milling of each identified grain, and finally the sputter yields were calculated from the removed volumes, which were measured by atomic force microscope. Experimental results showed that the sputter yield of the primary orientations for Mo varied as Y{sub (110)} > Y{sub (100)} > Y{sub (111)}, coincidental with the ranking of their planar atomic packing densities. The concept of transparency of ion in the crystalline substance was applied to elucidate these results. In addition, the result of (110) orientation exhibiting higher sputter yield is helpful for us to develop a Mo target with a higher deposition rate for use in industry. By changing the deformation process from straight rolling to cross rolling, the (110) texture intensity of the Mo target was significantly improved, and thus enhanced the deposition rate. - Highlights: • We used EBSD, FIB and AFM to measure the sputter yields of Mo in low-index planes. • The sputter yield of the primary orientations for Mo varied as Y{sub (110)} > Y{sub (100)} > Y{sub (111)}. • The transparency of ion was used to elucidate the differences in the sputter yield. • We improved the sputter rate of polycrystalline Mo target by adjusting its texture.

  18. Production of rare-earth atomic negative ion beams in a cesium-sputter-type negative ion source

    International Nuclear Information System (INIS)

    Davis, V.T.; Covington, A.M.; Duvvuri, S.S.; Kraus, R.G.; Emmons, E.D.; Kvale, T.J.; Thompson, J.S.

    2007-01-01

    The desire to study negative ion structure and negative ion-photon interactions has spurred the development of ion sources for use in research and industry. The many different types of negative ion sources available today differ in their characteristics and abilities to produce anions of various species. Thus the importance of choosing the correct type of negative ion source for a particular research or industrial application is clear. In this study, the results of an investigation on the production of beams composed of negatively-charged rare-earth ions from a cylindrical-cathode-geometry, cesium-sputter-type negative ion source are presented. Beams of atomic anions have been observed for most of the first-row rare-earth elements, with typical currents ranging from hundreds of picoamps to several nanoamps

  19. Comparison of the Al back contact deposited by sputtering, e-beam, or thermal evaporation for inverted perovskite solar cells

    Science.gov (United States)

    Wahl, Tina; Hanisch, Jonas; Ahlswede, Erik

    2018-04-01

    In this work, we present inverted perovskite solar cells with Al top electrodes, which were deposited by three different methods. Besides the widely used thermal evaporation of Al, we also used the industrially important high deposition rate processes sputtering and electron beam evaporation for aluminium electrodes and examined the influence of the deposition method on the solar cell performance. The current-voltage characteristics of as grown solar cells with sputtered and e-beam Al electrode show an s-shape due to damage done to the organic electronic transport layers (ETL) during Al deposition. It can be cured by a short annealing step at a moderate temperature so that fill factors  >60% and power conversion efficiencies of almost 12% with negligible hysteresis can be achieved. While solar cells with thermally evaporated Al electrode do not show an s-shape, they also exhibit a clear improvement after a short annealing step. In addition, we varied the thickness of the ETL consisting of a double layer ([6,6]-Phenyl-C61-butyric acid methyl ester and bathocuproine) and investigated the influence on the solar cell parameters for the three different Al deposition methods, which showed distinct dependencies on ETL thickness.

  20. 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.

  1. Improving the growth of Ge/Si islands by modulating the spacing between screen and accelerator grids in ion beam sputtering deposition system

    International Nuclear Information System (INIS)

    Yang, Jie; Zhao, Bo; Wang, Chong; Qiu, Feng; Wang, Rongfei; Yang, Yu

    2016-01-01

    Highlights: • Ge islands were prepared by ion beam sputtering with different grid-to-grid gaps. • Ge islands with larger sizes and low density are observed in 1-mm-spaced samples. • The island growth was determined by sputter energy and the quality of Si buffer. • The crystalline volume fraction of buffer must be higher than 72% to grow islands. - Abstract: Ge islands were fabricated on Si buffer layer by ion beam sputtering deposition with a spacing between the screen and accelerator grids of either 1 mm or 2 mm. The Si buffer layer exhibits mixed-phase microcrystallinity for samples grown with 1 mm spacing and crystallinity for those with 2 mm spacing. Ge islands are larger and less dense than those grown on the crystalline buffer because of the selective growth mechanism on the microcrystalline buffer. Moreover, the nucleation site of Ge islands formed on the crystalline Si buffer is random. Ge islands grown at different grid-to-grid gaps are characterized by two key factors, namely, divergence half angle of ion beam and crystallinity of buffer layer. High grid-to-grid spacing results in small divergence half angle, thereby enhancing the sputtering energy and redistribution of sputtered atoms. The crystalline volume fraction of the microcrystalline Si buffer was obtained based on the integrated intensity ratio of Raman peaks. The islands show decreased density with decreasing crystalline volume fraction and are difficult to observe at crystalline volume fractions lower than 72%.

  2. Improving the growth of Ge/Si islands by modulating the spacing between screen and accelerator grids in ion beam sputtering deposition system

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jie; Zhao, Bo [Institute of Optoelectronic Information Materials, School of Materials Science and Engineering, Yunnan University, Kunming 650091 (China); Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming 650091 (China); Wang, Chong, E-mail: cwang@mail.sitp.ac.cn [Institute of Optoelectronic Information Materials, School of Materials Science and Engineering, Yunnan University, Kunming 650091 (China); Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming 650091 (China); Qiu, Feng; Wang, Rongfei [Institute of Optoelectronic Information Materials, School of Materials Science and Engineering, Yunnan University, Kunming 650091 (China); Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming 650091 (China); Yang, Yu, E-mail: yuyang@ynu.edu.cn [Institute of Optoelectronic Information Materials, School of Materials Science and Engineering, Yunnan University, Kunming 650091 (China); Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming 650091 (China)

    2016-11-15

    Highlights: • Ge islands were prepared by ion beam sputtering with different grid-to-grid gaps. • Ge islands with larger sizes and low density are observed in 1-mm-spaced samples. • The island growth was determined by sputter energy and the quality of Si buffer. • The crystalline volume fraction of buffer must be higher than 72% to grow islands. - Abstract: Ge islands were fabricated on Si buffer layer by ion beam sputtering deposition with a spacing between the screen and accelerator grids of either 1 mm or 2 mm. The Si buffer layer exhibits mixed-phase microcrystallinity for samples grown with 1 mm spacing and crystallinity for those with 2 mm spacing. Ge islands are larger and less dense than those grown on the crystalline buffer because of the selective growth mechanism on the microcrystalline buffer. Moreover, the nucleation site of Ge islands formed on the crystalline Si buffer is random. Ge islands grown at different grid-to-grid gaps are characterized by two key factors, namely, divergence half angle of ion beam and crystallinity of buffer layer. High grid-to-grid spacing results in small divergence half angle, thereby enhancing the sputtering energy and redistribution of sputtered atoms. The crystalline volume fraction of the microcrystalline Si buffer was obtained based on the integrated intensity ratio of Raman peaks. The islands show decreased density with decreasing crystalline volume fraction and are difficult to observe at crystalline volume fractions lower than 72%.

  3. Low-damage high-throughput grazing-angle sputter deposition on graphene

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.-T.; Gajek, M.; Raoux, S. [IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Casu, E. A. [IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Politecnico di Torino, Turin 10129 (Italy)

    2013-07-15

    Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications.

  4. Low-damage high-throughput grazing-angle sputter deposition on graphene

    International Nuclear Information System (INIS)

    Chen, C.-T.; Gajek, M.; Raoux, S.; Casu, E. A.

    2013-01-01

    Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications

  5. Low-damage high-throughput grazing-angle sputter deposition on graphene

    Science.gov (United States)

    Chen, C.-T.; Casu, E. A.; Gajek, M.; Raoux, S.

    2013-07-01

    Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications.

  6. Specific features of fullerene-bearing thin film growth using ion beam vacuum sputtering of fullerene mixtures with B, Fe, Se, Gd and Na

    International Nuclear Information System (INIS)

    Semenov, A.P.; Semenova, I.A.; Bulina, N.V.; Lopatin, V.A.; Karmanov, N.S.; Churilov, G.N.

    2005-01-01

    A new approach to the growth of films containing fullerenes and doping elements is described. It is suggested that a cluster mechanism of the target sputtering by accelerated ions makes possible the deposition of fullerenes on a substrate with a certain probability for dopant atoms being introduced into the cavities of fullerene molecules and a higher probability of the doping element introduction between fullerene molecules. The proposed method has been experimentally implemented by using an Ar ion beam to sputter C 60 /C 70 fullerene mixtures, synthesized in a plasmachemical reactor at a pressure of 10 5 Pa and containing a doping element, i.e. Fe, Na, B, Gd or Se. Micron-thick films containing C 60 and C 70 fullerenes and the corresponding dopant element, i.e. Fe, Na, B, Gd or Se, were grown from dopant-containing fullerene mixtures by ion beam sputtering in a vacuum of ∼10 -2 Pa [ru

  7. Effect of argon ion beam voltages on the microstructure of aluminum nitride films prepared at room temperature by a dual ion beam sputtering system

    International Nuclear Information System (INIS)

    Chen, H.-Y.; Han Sheng; Cheng, C.-H.; Shih, H.C.

    2004-01-01

    Aluminum nitride (AlN) films were successfully deposited at room temperature onto p-type (1 0 0) silicon wafers by manipulating argon ion beam voltages in a dual ion beam sputtering (DIBS). X-ray diffraction spectra showed that aluminum nitride films could be synthesized above 800 V. The (0 0 2) orientation was dominant at 800 V, above which the orientation was random. The atomic force microscope (AFM) images displayed a relatively smooth surface with the root-mean-square roughness of 2-3 nm, where this roughness decreased with argon ion beam voltage. The Al 2p 3/2 and N 1s spectra indicated that both the aluminum-aluminum bond and aluminum-nitrogen bond appeared at 600 V, above which only the aluminum-nitrogen bond was detected. Moreover, the atomic concentration in aluminum nitride films was concentrated in aluminum-rich phases in all cases. Nevertheless, the aluminum concentration markedly increased with argon ion beam voltages below 1000 V, above which the concentration decreased slightly. The correlation between the microstructure of aluminum nitride films and argon ion beam voltages is also discussed

  8. Multi-jump magnetic switching in ion-beam sputtered amorphous Co20Fe60B20 thin films

    International Nuclear Information System (INIS)

    Raju, M.; Chaudhary, Sujeet; Pandya, D. K.

    2013-01-01

    Unconventional multi-jump magnetization reversal and significant in-plane uniaxial magnetic anisotropy (UMA) in the ion-beam sputtered amorphous Co 20 Fe 60 B 20 (5–75 nm) thin films grown on Si/amorphous SiO 2 are reported. While such multi-jump behavior is observed in CoFeB(10 nm) film when the magnetic field is applied at 10°–20° away from the easy-axis, the same is observed in CoFeB(12.5 nm) film when the magnetic field is 45°–55° away from easy-axis. Unlike the previous reports of multi-jump switching in epitaxial films, their observance in the present case of amorphous CoFeB is remarkable. This multi-jump switching is found to disappear when the films are crystallized by annealing at 420 °C. The deposition geometry and the energy of the sputtered species appear to intrinsically induce a kind of bond orientation anisotropy in the films, which leads to the UMA in the as-grown amorphous CoFeB films. Exploitation of such multi-jump switching in amorphous CoFeB thin films could be of technological significance because of their applications in spintronic devices

  9. The influence of sequence of precursor films on CZTSe thin films prepared by ion-beam sputtering deposition

    Science.gov (United States)

    Zhao, Jun; Liang, Guangxing; Zeng, Yang; Fan, Ping; Hu, Juguang; Luo, Jingting; Zhang, Dongping

    2017-02-01

    The CuZnSn (CZT) precursor thin films are grown by ion-beam sputtering Cu, Zn, Sn targets with different orders and then sputtering Se target to fabricate Cu2ZnSnSe4 (CZTSe) absorber thin films on molybdenum substrates. They are annealed in the same vacuum chamber at 400 °C. The characterization methods of CZTSe thin films include X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray photoelectron spectra (XPS) in order to study the crystallographic properties, composition, surface morphology, electrical properties and so on. The results display that the CZTSe thin films got the strongest diffraction peak intensity and were with good crystalline quality and its morphology appeared smooth and compact with a sequence of Cu/Zn/Sn/Se, which reveals that the expected states for CZTSe are Cu1+, Zn2+, Sn4+, Se2+. With the good crystalline quality and close to ideal stoichiometric ratio the resistivity of the CZTSe film with the sequence of Cu/Zn/Sn/Se is lower, whose optical band gap is about 1.50 eV. Project supported by the National Natural Science Foundation of China (No. 61404086), the Basical Research Program of Shenzhen (Nos. JCYJ20150324140036866, JCYJ20150324141711581), and the Natural Science Foundation of SZU (No. 2014017).

  10. The effect of FR enhancement in reactive ion beam sputtered Bi, Gd, Al-substituted iron- garnets: Bi2O3 nanocomposite films

    OpenAIRE

    Berzhansky, V.; Shaposhnikov, A.; Karavainikov, A.; Prokopov, A.; Mikhailova, T.; Lukienko, I.; Kharchenko, Yu.; Miloslavskaya, O.; Kharchenko, N.

    2012-01-01

    The effect of considerable Faraday rotation (FR) and figure of merit (Q) enhancement in Bi, Gd, Al-substituted iron garnets: Bi2O3 nano-composite films produced by separate reactive ion beam sputtered Bi:YIG and Bi2O3 films was found. It reached threefold enhancement of the FR and twofold of the Q one on GGG substrates.

  11. Moving strip technique of electron beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, Kishio; Wakasa, Hiroyuki; Oguri, Nobuhiro; Kitayama, Takuichi; Nakagiri, Yoshitada; Mikami, Yasutaka; Hashimoto, Keiji; Hiraki, Yoshio; Aono, Kaname

    1984-12-01

    The fieldsize in electron beam therapy is determined by the cone size. In case of skin metastasis of a malignant tumor and so on, which need a large field size and whose area is much larger than the size of the cone, a large field size is usually produced by dividing the portals. However, the dose distribution at the border of the field becomes unequal, and hot and cold dose areas are produced according to the distance between portals. We tried the strip field technique in a large field along the long axis of the body in order to flatten the dose of the border employing the moving strip used for whole abdominal irradiation in ovarian cancer. We set the film in Mix-DP and used the strip field technique with 2.5cm steps. We discussed the relationship between the interval (distance between portals) and the flattening of the dose within the field. Skin movement due to breathing and influences on the flattening of the dose were considered. The proper flatness was obtained at depths of 0,1,2, and 3cm by setting the interval at 0.5cm. When skin movement was produced by breathing in +-1.5mm, the proper flaness was obtained also at a 0.5-cm interval. It seems that smoothing is increased by breathing. An ''electron beam moving strip'' with a 2.5-cm step and 0.5-cm interval was clinically effective in the treatment of patients with skin metastasis of colon cancer. (author).

  12. Electron beam induced coloration and luminescence in layered structure of WO3 thin films grown by pulsed dc magnetron sputtering

    International Nuclear Information System (INIS)

    Karuppasamy, A.; Subrahmanyam, A.

    2007-01-01

    Tungsten oxide thin films have been deposited by pulsed dc magnetron sputtering of tungsten in argon and oxygen atmosphere. The as-deposited WO 3 film is amorphous, highly transparent, and shows a layered structure along the edges. In addition, the optical properties of the as-deposited film show a steplike behavior of extinction coefficient. However, the electron beam irradiation (3.0 keV) of the as-deposited films results in crystallization, coloration (deep blue), and luminescence (intense red emission). The above changes in physical properties are attributed to the extraction of oxygen atoms from the sample and the structural modifications induced by electron bombardment. The present method of coloration and luminescence has a potential for fabricating high-density optical data storage device

  13. Electron Beam Polarization Measurement Using Touschek Lifetime Technique

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Changchun; /Duke U., DFELL; Li, Jingyi; /Duke U., DFELL; Mikhailov, Stepan; /Duke U., DFELL; Popov, Victor; /Duke U., DFELL; Wu, Wenzhong; /Duke U., DFELL; Wu, Ying; /Duke U., DFELL; Chao, Alex; /SLAC; Xu, Hong-liang; /Hefei, NSRL; Zhang, Jian-feng; /Hefei, NSRL

    2012-08-24

    Electron beam loss due to intra-beam scattering, the Touschek effect, in a storage ring depends on the electron beam polarization. The polarization of an electron beam can be determined from the difference in the Touschek lifetime compared with an unpolarized beam. In this paper, we report on a systematic experimental procedure recently developed at Duke FEL laboratory to study the radiative polarization of a stored electron beam. Using this technique, we have successfully observed the radiative polarization build-up of an electron beam in the Duke storage ring, and determined the equilibrium degree of polarization and the time constant of the polarization build-up process.

  14. Nanoripple formation on GaAs (001) surface by reverse epitaxy during ion beam sputtering at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Debasree; Ghose, Debabrata, E-mail: debabrata1.ghose@gmail.com

    2016-11-01

    Highlights: • GaAs (001) surfaces are sputtered by 1 keV Ar{sup +} at sample temperature of 450 °C. • Highly ordered defect-free ripples develop at near-normal incidence angles (θ ≈ 0–25{sup 0}). • Concurrent sample rotation does not alter the ripple orientation with respect to the ion beam. • At grazing incidence angles anisotropic structure is formed. • Concurrent sample rotation shows that the structure orientation depends on the beam direction. - Abstract: Self-organized pattern formation by the process of reverse epitaxial growth has been investigated on GaAs (001) surfaces during 1 keV Ar{sup +} bombardment at target temperature of 450 °C for a wide range of incident angles. Highly ordered ripple formation driven by diffusion instability is evidenced at near normal incidence angles. Concurrent sample rotation shows that the ripple morphology and its orientation do not depend on the incident beam direction; rather they are determined by the symmetry of the crystal face.

  15. Temperature dependence of the optical properties of ion-beam sputtered ZrN films

    Energy Technology Data Exchange (ETDEWEB)

    Larijani, M.M. [NSTRI, AEOI, Radiation Applications Research School, Karaj (Iran, Islamic Republic of); Kiani, M. [Azad University, South Tehran Branch, Department of Physics, Tehran (Iran, Islamic Republic of); Jafari-Khamse, E. [NSTRI, AEOI, Radiation Applications Research School, Karaj (Iran, Islamic Republic of); University of Kashan, Department of Physics, Kashan (Iran, Islamic Republic of); Fathollahi, V. [Nuclear Science Research School, NSTRI, Tehran (Iran, Islamic Republic of)

    2014-11-15

    The reflectivity of sputtered Zirconium nitride films on glass substrate has been investigated in the spectral energy range of 0.8-6.1 eV as a function of deposition temperature varying between 373 and 723 K. Optical constants of the prepared films have been determined using the Drude analysis. Experimental results showed strong dependency of optical properties of the films, such as optical resistivity on the substrate temperature. The temperature increase of the substrate has shown an increase in both the plasmon frequency and electron scattering time. The electrical behavior of the films showed a good agreement between their optical and electrical resistivity. (orig.)

  16. Argonne inverted sputter source

    International Nuclear Information System (INIS)

    Yntema, J.L.; Billquist, P.J.

    1983-01-01

    The emittance of the inverted sputter source with immersion lenses was measured to be about 5π mm mrad MeV/sup 1/2/ at the 75% level over a wide range of beam intensities. The use of the source in experiments with radioactive sputter targets and hydrogen loaded targets is described. Self contamination of the source is discussed

  17. High current density ion beam measurement techniques

    International Nuclear Information System (INIS)

    Ko, W.C.; Sawatzky, E.

    1976-01-01

    High ion beam current measurements are difficult due to the presence of the secondary particles and beam neutralization. For long Faraday cages, true current can be obtained only by negative bias on the target and by summing the cage wall and target currents; otherwise, the beam will be greatly distorted. For short Faraday cages, a combination of small magnetic field and the negative target bias results in correct beam current. Either component alone does not give true current

  18. Ultraviolet optical and microstructural properties of MgF2 and LaF3 coatings deposited by ion-beam sputtering and boat and electron-beam evaporation

    Science.gov (United States)

    Ristau, Detlev; Gunster, Stefan; Bosch, Salvador; Duparre, Angela; Masetti, Enrico; Ferre-Borrull, Josep; Kiriakidis, George; Peiro, Francesca; Quesnel, Etienne; Tikhonravov, Alexander

    2002-06-01

    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 approx1.80 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.

  19. Study of ion beam sputtered Fe/Si interfaces as a function of Si layer thickness

    Science.gov (United States)

    Kumar, Anil; Brajpuriya, Ranjeet; Singh, Priti

    2018-01-01

    The exchange interaction in metal/semiconductor interfaces is far from being completely understood. Therefore, in this paper, we have investigated the nature of silicon on the Fe interface in the ion beam deposited Fe/Si/Fe trilayers keeping the thickness of the Fe layers fixed at 3 nm and varying the thickness of the silicon sandwich layer from 1.5 nm to 4 nm. Grazing incidence x-ray diffraction and atomic force microscopy techniques were used, respectively, to study the structural and morphological changes in the deposited films as a function of layer thickness. The structural studies show silicide formation at the interfaces during deposition and better crystalline structure of Fe layers at a lower spacer layer thickness. The magnetization behavior was investigated using magneto-optical Kerr effect, which clearly shows that coupling between the ferromagnetic layers is highly influenced by the semiconductor spacer layer thickness. A strong antiferromagnetic coupling was observed for a value of tSi = 2.5 nm but above this value an unexpected behavior of hysteresis loop (step like) with two coercivity values is recorded. For spacer layer thickness greater than 2.5 nm, an elemental amorphous Si layer starts to appear in the spacer layer in addition to the silicide layer at the interfaces. It is observed that in the trilayer structure, Fe layers consist of various stacks, viz., Si doped Fe layers, ferromagnetic silicide layer, and nonmagnetic silicide layer at the interfaces. The two phase hysteresis loop is explained on the basis of magnetization reversal of two ferromagnetic layers, independent of each other, with different coercivities. X-ray photo electron spectroscopy technique was also used to study interfaces characteristics as a function of tSi.

  20. Sputtered Encapsulation as Wafer Level Packaging for Isolatable MEMS Devices: A Technique Demonstrated on a Capacitive Accelerometer

    Directory of Open Access Journals (Sweden)

    Azrul Azlan Hamzah

    2008-11-01

    Full Text Available This paper discusses sputtered silicon encapsulation as a wafer level packaging approach for isolatable MEMS devices. Devices such as accelerometers, RF switches, inductors, and filters that do not require interaction with the surroundings to function, could thus be fully encapsulated at the wafer level after fabrication. A MEMSTech 50g capacitive accelerometer was used to demonstrate a sputtered encapsulation technique. Encapsulation with a very uniform surface profile was achieved using spin-on glass (SOG as a sacrificial layer, SU-8 as base layer, RF sputtered silicon as main structural layer, eutectic gold-silicon as seal layer, and liquid crystal polymer (LCP as outer encapsulant layer. SEM inspection and capacitance test indicated that the movable elements were released after encapsulation. Nanoindentation test confirmed that the encapsulated device is sufficiently robust to withstand a transfer molding process. Thus, an encapsulation technique that is robust, CMOS compatible, and economical has been successfully developed for packaging isolatable MEMS devices at the wafer level.

  1. Flush-mounting technique for composite beams

    Science.gov (United States)

    Harman, T. C.; Kay, B. F.

    1980-01-01

    Procedure permits mounting of heavy parts to surface of composite beams without appreciably weakening beam web. Web is split and held apart in region where attachment is to be made by lightweight precast foam filler. Bolt hole penetrates foam rather than web, and is secured by barrelnut in transverse bushing through web.

  2. Highly ordered nanopatterns on Ge and Si surfaces by ion beam sputtering

    International Nuclear Information System (INIS)

    Ziberi, B; Cornejo, M; Frost, F; Rauschenbach, B

    2009-01-01

    The bombardment of surfaces with low-energy ion beams leads to material erosion and can be accompanied by changes in the topography. Under certain conditions this surface erosion can result in well-ordered nanostructures. Here an overview of the pattern formation on Si and Ge surfaces under low-energy ion beam erosion at room temperature will be given. In particular, the formation of ripple and dot patterns, and the influence of different process parameters on their formation, ordering, shape and type will be discussed. Furthermore, the internal ion beam parameters inherent to broad beam ion sources are considered as an additional degree of freedom for controlling the pattern formation process. In this context: (i) formation of ripples at near-normal ion incidence, (ii) formation of dots at oblique ion incidence without sample rotation, (iii) transition between patterns, (iv) formation of ripples with different orientations and (v) long range ordered dot patterns will be presented and discussed.

  3. Sputtering as a means of depth profiling

    International Nuclear Information System (INIS)

    Whitton, J.L.

    1978-01-01

    Probably the most common technique for determination of depth profiles by sputtering is that of secondary ion mass spectrometry. Many problems occur in the important step of converting the time (of sputtering) scale to a depth scale and these problems arise before the secondary ions are ejected. An attempt is made to present a comprehensive list of the effects that should be taken into consideration in the use of sputtering as a means of depth profiling. The various parameters liable to affect the depth profile measurements are listed in four sections: beam conditions; target conditions; experimental environment; and beam-target interactions. The effects are discussed and where interplay occurs, cross-reference is made and examples are provided where possible. (B.R.H.)

  4. Development of an ion-beam sputtering system for depositing thin films and multilayers of alloys and compounds

    International Nuclear Information System (INIS)

    Gupta, Mukul; Gupta, Ajay; Phase, D.M.; Chaudhari, S.M.; Dasannacharya, B.A.

    2002-01-01

    An ion-beam sputtering (IBS) system has been designed and developed for preparing thin films and multilayers of various elements, alloys and compounds. The ion source used is a 3 cm diameter, hot-cathode Kaufman type 1.5 kV ion source. The system has been successfully tested with the deposition of various materials, and the deposition parameters were optimised for achieving good quality of thin films and multilayers. A systematic illustration of the versatility of the system to produce a variety of structures is done by depositing thin film of pure iron, an alloy film of Fe-Zr, a compound thin film of FeN, a multilayer of Fe-Ag and an isotopic multilayer of 57 FeZr/FeZr. Microstructural measurements on these films using X-ray and neutron reflectivity, atomic force microscopy (AFM), and X-ray diffraction are presented and discussed to reveal the quality of the microstructures obtained with the system. It is found that in general, the surface roughnesses of the film deposited by IBS are significantly smaller as compared to those for films deposited by e-beam evaporation. Further, the grain size of the IBS crystalline films is significantly refined as compared to the films deposited by e-beam evaporation. Grain refinement may be one of the reasons for reduced surface roughness. In the case of amorphous films, the roughness of the films does not increase appreciably beyond that of the substrate even after depositing thicknesses of several hundred angstroms

  5. Reactive sputter deposition

    CERN Document Server

    Mahieu, Stijn

    2008-01-01

    In this valuable work, all aspects of the reactive magnetron sputtering process, from the discharge up to the resulting thin film growth, are described in detail, allowing the reader to understand the complete process. Hence, this book gives necessary information for those who want to start with reactive magnetron sputtering, understand and investigate the technique, control their sputtering process and tune their existing process, obtaining the desired thin films.

  6. Spectral artefacts post sputter-etching and how to cope with them - A case study of XPS on nitride-based coatings using monoatomic and cluster ion beams

    Science.gov (United States)

    Lewin, Erik; Counsell, Jonathan; Patscheider, Jörg

    2018-06-01

    The issue of artefacts due to sputter-etching has been investigated for a group of AlN-based thin film materials with varying thermodynamical stability. Stability of the materials was controlled by alloying AlN with the group 14 elements Si, Ge or Sn in two different concentrations. The coatings were sputter-etched with monoatomic Ar+ with energies between 0.2 and 4.0 keV to study the sensitivity of the materials for sputter damage. The use of Arn+ clusters to remove an oxidised surface layer was also evaluated for a selected sample. The spectra were compared to pristine spectra obtained after in-vacuo sample transfer from the synthesis chamber to the analysis instrument. It was found that the all samples were affected by high energy (4 keV) Ar+ ions to varying degrees. The determining factors for the amount of observed damage were found to be the materials' enthalpy of formation, where a threshold value seems to exist at approximately -1.25 eV/atom (∼-120 kJ/mol atoms). For each sample, the observed amount of damage was found to have a linear dependence to the energy deposited by the ion beam per volume removed material. Despite the occurrence of sputter-damage in all samples, etching settings that result in almost artefact-free spectral data were found; using either very low energy (i.e. 200 eV) monoatomic ions, or an appropriate combination of ion cluster size and energy. The present study underlines that analysis post sputter-etching must be carried out with an awareness of possible sputter-induced artefacts.

  7. Characterization of ZnO:SnO{sub 2} (50:50) thin film deposited by RF magnetron sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Cynthia, S. R.; Sanjeeviraja, C.; Ponmudi, S. [Department of Physics, Alagappa Chettiar College of Engineering and Technology, Karaikudi-630004 (India); Sivakumar, R., E-mail: krsivakumar1979@yahoo.com [Directorate of Distance Education, Alagappa University, Karaikudi-630004 (India)

    2016-05-06

    Zinc oxide (ZnO) and tin oxide (SnO{sub 2}) thin films have attracted significant interest recently for use in optoelectronic application such as solar cells, flat panel displays, photonic devices, laser diodes and gas sensors because of their desirable electrical and optical properties and wide band gap. In the present study, thin films of ZnO:SnO{sub 2} (50:50) were deposited on pre-cleaned microscopic glass substrate by RF magnetron sputtering technique. The substrate temperature and RF power induced changes in structural, surface morphological, compositional and optical properties of the films have been studied.

  8. HF treatment effect for carbon deposition on silicon (111) by DC sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Aji, A. S., E-mail: aji.ravazes70@gmail.com; Darma, Y., E-mail: aji.ravazes70@gmail.com [Quantum Semiconductor and Devices Lab., Physics of Material Electronics Research Division, Department of Physics, Institut Teknologi Bandung (Indonesia)

    2014-03-24

    Surface modifications of Si (111) substrate by HF solution for thin film carbon deposition have been systematically studied. Thin film carbon on Si (111) has been deposited using DC Unbalanced Magnetron Sputtering with carbon pellet doped by 5% Fe as the target. EDAX characterization confirmed that the carbon fraction on Si substrate much higher by dipping a clean Si substrate by HF solution before sputtering process in comparison with carbon fraction on Si substrate just after conventional RCA. Moreover, SEM and AFM images show the uniform thin film carbon on Si with HF treatment, in contrast to the Si without HF solution treatment. These experimental results suggest that HF treatment of Si surface provide Si-H bonds on top Si surface that useful to enhance the carbon deposition during sputtering process. Furthermore, we investigate the thermal stability of thin film carbon on Si by thermal annealing process up to 900 °C. Atomic arrangements during annealing process were characterized by Raman spectroscopy. Raman spectra indicate that thin film carbon on Si is remaining unchanged until 600 °C and carbon atoms start to diffuse toward Si substrate after annealing at 900 °C.

  9. Acceleration of 14C beams in electrostatic accelerators

    International Nuclear Information System (INIS)

    Rowton, L.J.; Tesmer, J.R.

    1981-01-01

    Operational problems in the production and acceleration of 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators and personnel are described. Sputter source target fabrication techniques and the relative beam production efficiencies of various types of bound particulate carbon sputter source targets are presented

  10. Spin pumping in ion-beam sputtered C o2FeAl /Mo bilayers: Interfacial Gilbert damping

    Science.gov (United States)

    Husain, Sajid; Kumar, Ankit; Barwal, Vineet; Behera, Nilamani; Akansel, Serkan; Svedlindh, Peter; Chaudhary, Sujeet

    2018-02-01

    The spin-pumping mechanism and associated interfacial Gilbert damping are demonstrated in ion-beam sputtered C o2FeAl (CFA)/Mo bilayer thin films employing ferromagnetic resonance spectroscopy. The dependence of the net spin-current transportation on Mo layer thickness, 0 to 10 nm, and the enhancement of the net effective Gilbert damping are reported. The experimental data have been analyzed using spin-pumping theory in terms of spin current pumped through the ferromagnet/nonmagnetic metal interface to deduce the real spin-mixing conductance and the spin-diffusion length, which are estimated to be 1.56 (±0.30 ) ×1019m-2 and 2.61 (±0.15 )nm , respectively. The damping constant is found to be 8.8 (±0.2 ) ×10-3 in the Mo(3.5 nm)-capped CFA(8 nm) sample corresponding to an ˜69 % enhancement of the original Gilbert damping 5.2 (±0.6 ) ×10-3 in the Al-capped CFA thin film. This is further confirmed by inserting the Cu dusting layer which reduces the spin transport across the CFA/Mo interface. The Mo layer thickness-dependent net spin-current density is found to lie in the range of 1 -4 MA m-2 , which also provides additional quantitative evidence of spin pumping in this bilayer thin-film system.

  11. Effect of heat treatment on properties of HfO2 film deposited by ion-beam sputtering

    Science.gov (United States)

    Liu, Huasong; Jiang, Yugang; Wang, Lishuan; Li, Shida; Yang, Xiao; Jiang, Chenghui; Liu, Dandan; Ji, Yiqin; Zhang, Feng; Chen, Deying

    2017-11-01

    The effects of atmosphere heat treatment on optical, stress, and microstructure properties of an HfO2 film deposited by ion-beam sputtering were systematically researched. The relationships among annealing temperature and refractive index, extinction coefficient, physical thickness, forbidden-band width, tape trailer width, Urbach energy, crystal phase structure, and stress were assessed. The results showed that 400 °C is the transformation point, and the microstructure of the HfO2 film changed from an amorphous into mixed-phase structure. Multistage phonons appeared on the HfO2 film, and the trends of the refractive index, extinction coefficient, forbidden-band width change, and Urbach energy shifted from decrease to increase. With the elevation of the annealing temperature, the film thickness increased monotonously, the compressive stress gradually turned to tensile stress, and the transformation temperature point for the stress was between 200 °C and 300 °C. Therefore, the change in the stress is the primary cause for the shifts in thin-film thickness.

  12. Thermoelectric properties of bismuth antimony tellurium thin films through bilayer annealing prepared by ion beam sputtering deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Zhuang-hao [College of Physics Science and Technology, Shenzhen University, 518060 (China); Shenzhen Key Laboratory of Sensor Technology, Shenzhen 518060 (China); Fan, Ping, E-mail: fanping308@126.com [College of Physics Science and Technology, Shenzhen University, 518060 (China); Shenzhen Key Laboratory of Sensor Technology, Shenzhen 518060 (China); Luo, Jing-ting [College of Physics Science and Technology, Shenzhen University, 518060 (China); Shenzhen Key Laboratory of Sensor Technology, Shenzhen 518060 (China); Cai, Xing-min; Liang, Guang-xing; Zhang, Dong-ping [College of Physics Science and Technology, Shenzhen University, 518060 (China); Ye, Fan [Shenzhen Key Laboratory of Sensor Technology, Shenzhen 518060 (China)

    2014-07-01

    Bismuth antimony tellurium is one of the most important tellurium-based materials for high-efficient thermoelectric application. In this paper, ion beam sputtering was used to deposit Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} bilayer thin films on borosilicate substrates at room-temperature. Then the bismuth antimony tellurium thin films were synthesized via post thermal treatment of the Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} bilayer thin films. The effect of annealing temperature and compositions on the thermoelectric properties of the thin films was investigated. After the thin films were annealed from 150 °C to 350 °C for 1 h in the high vacuum condition, the Seebeck coefficient changed from a negative sign to a positive sign. The X-ray diffraction results showed that the synthesized tellurium-based thermoelectric thin film exhibited various alloys phases, which contributed different thermoelectricity conductivity to the synthesized thin film. The overall Seebeck coefficient of the synthesized thin film changed from negative sign to positive sign, which was due to the change of the primary phase of the tellurium-based materials at different annealing conditions. Similarly, the thermoelectric properties of the films were also associated with the grown phase. High-quality thin film with the Seebeck coefficient of 240 μV K{sup −1} and the power factor of 2.67 × 10{sup −3} Wm{sup −1} K{sup −2} showed a single Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} phase when the Sb/Te thin film sputtering time was 40 min. - Highlights: • Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} thermoelectric thin films synthesized via bilayer annealing • The film has single Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} phase with best thermoelectric performance. • The film has high thermoelectric properties comparable with other best results.

  13. Fundamental aspects of cathodic sputtering

    International Nuclear Information System (INIS)

    Harman, R.

    1979-01-01

    The main fundamental aspects and problems of cathodic sputtering used mainly for thin film deposition and sputter etching are discussed. Among many types of known sputtering techniques the radiofrequency /RF/ diode sputtering is the most universal one and is used for deposition of metals, alloys, metallic compounds, semiconductors and insulators. It seems that nowadays the largest number of working sputtering systems is of diode type. Sometimes also the dc or rf triode sputtering systems are used. The problems in these processes are practically equivalent and comparable with the problems in the diode method and therefore our discussion will be, in most cases applicable for both, the diode and triode methods

  14. Directed ion beam sputter etching of polytetrafluorethylene (teflon) using an argon ion source

    Energy Technology Data Exchange (ETDEWEB)

    Garner, C E; Gabriel, S B; Kuo, Y S

    1982-09-24

    Polytetrafluoroethylene (Teflon) tubes of outside diameter 375-625 ..mu..m were perforated by bombarding the tubes with an argon ion beam. Holes of diameter 18 ..mu..m and 40 ..mu..m on a side and open-are ratios of 55% and 65% respectively were formed using electroformed nickel mesh masks. Scanning electron micrographs of the hole walls reveal that they are relatively smooth and that the holes go completely through the tubing walls. Holes with the smoothest walls and the sharpest definition were obtained by using low beam power densities and a tubing target temperature of less than 50/sup 0/C. Volumetric flow rate measurements show that the flow rate through the perforated tubules is 0.2-0.5 cm/sup 3/ min/sup -1/ for a pressure drop across the tubes of 2.2 Torr. The perforated microtubules have an important application in medicine for sufferers of hydrocephalus, a malady which results in the build-up of cerebrospinal fluid in the brain. The perforated tubing is inserted into the ventricle and serves as a shunt by draining off the excess cerebrospinal fluid into another part of the brain, where the fluid is absorbed by normal processes.

  15. Surface structuring in polypropylene using Ar+ beam sputtering: Pattern transition from ripples to dot nanostructures

    Science.gov (United States)

    Goyal, Meetika; Aggarwal, Sanjeev; Sharma, Annu; Ojha, Sunil

    2018-05-01

    Temporal variations in nano-scale surface morphology generated on Polypropylene (PP) substrates utilizing 40 keV oblique argon ion beam have been presented. Due to controlled variation of crucial beam parameters i.e. ion incidence angle and erosion time, formation of ripple patterns and further its transition into dot nanostructures have been realized. Experimental investigations have been supported by evaluation of Bradley and Harper (B-H) coefficients estimated using SRIM (The Stopping and Range of Ions in Matter) simulations. Roughness of pristine target surfaces has been accredited to be a crucial factor behind the early time evolution of nano-scale patterns over the polymeric surface. Study of Power spectral density (PSD) spectra reveals that smoothing mechanism switch from ballistic drift to ion enhanced surface diffusion (ESD) which can be the most probable cause for such morphological transition under given experimental conditions. Compositional analysis and depth profiling of argon ion irradiated specimens using Rutherford Backscattering Spectroscopy (RBS) has also been correlated with the AFM findings.

  16. Automation of neutral beam source conditioning with artificial intelligence techniques

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.W.; Lager, D.L.

    1985-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques. The architecture of the system is presented followed by a description of its performance

  17. Automation of neutral beam source conditioning with artificial intelligence techniques

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.; Lager, D.

    1986-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques. The architecture of the system is presented followed by a description of its performance

  18. The influence of target structure on topographical features produced by ion beam sputtering

    International Nuclear Information System (INIS)

    Whitton, J.L.; Grant, W.A.

    1981-01-01

    Ion beam erosion of solid surfaces often results in the development of distinctive topographical features. The relationship between the type of features formed by ion erosion and target structure has been investigated. Single crystals of copper and nickel and the amorphous alloy Metglas have been bombarded to high doses (approx. >=10 19 ions cm -2 ) with 40 keV Ar + and P + . Topography changes were monitored using SEM and structural changes by TEM. Targets that retain their long range crystallinity show sharply defined, regular features that are related to the target structure. Targets that are highly disordered, either intrinsically or as a result of the ion bombardment, produce diffuse, smaller features. Those differences are observed at all stages in topographical evolution. (orig.)

  19. Effects of nitrogen gas ratio on the structural and corrosion properties of ZrN thin films grown on biodegradable magnesium alloy by ion-beam sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Kiahosseini, Seyed Rahim [Islamic Azad University, Department of Engineering, Damghan Branch, Damghan (Iran, Islamic Republic of); Mojtahedzadeh Larijani, Majid [Nuclear Sciences and Technology Institute, Radiation Application Research School, Tehran (Iran, Islamic Republic of)

    2017-12-15

    Studies on the corrosion resistance of magnesium alloys, which are widely applied as biomaterials, have increased in recent years. In this work, zirconium nitride (ZrN) coatings were deposited on AZ91 magnesium alloy through ion-beam sputtering at 473 K with 0.3, 0.4, 0.5, and 0.6 nitrogen proportions [F(N{sub 2})] in ionized gas. X-ray diffraction, profilometry, hardness tests, scanning electron microscopy, and potentiodynamic polarization techniques were used to analyze the structure, thickness, adhesion, microstructure, and corrosion resistance of coated samples, respectively. Results showed that the (111) crystalline orientation dominated in all coatings. Williamson-Hall technique revealed that the crystallite size of ZrN films decreased from 73 to 20 nm with increasing F(N{sub 2}), and compressive microstrain increased from 0.004 to 0.030. Film thicknesses were inversely correlated with N{sub 2} amount and significantly decreased from 1.7 to 0.8 μm. The maximum dP/dr ratio, a dependent factor of adhesion, was 0.04 kg/cm for the film deposited under the F(N{sub 2}) value of 0.5. The corrosion potential of coated samples was not significantly different from that of uncoated AZ91. Under the F(N{sub 2}) value of 0.6, corrosion current density slightly decreased from 14 to 9.7 μA/cm{sup 2} and significantly increased to 13.5 μA/cm{sup 2}. Results indicated that ZrN film deposited under the F(N{sub 2}) value of 0.5 showed high adhesion and corrosion resistance. (orig.)

  20. Effects of nitrogen gas ratio on the structural and corrosion properties of ZrN thin films grown on biodegradable magnesium alloy by ion-beam sputtering

    Science.gov (United States)

    Kiahosseini, Seyed Rahim; Mojtahedzadeh Larijani, Majid

    2017-12-01

    Studies on the corrosion resistance of magnesium alloys, which are widely applied as biomaterials, have increased in recent years. In this work, zirconium nitride (ZrN) coatings were deposited on AZ91 magnesium alloy through ion-beam sputtering at 473 K with 0.3, 0.4, 0.5, and 0.6 nitrogen proportions [F(N2)] in ionized gas. X-ray diffraction, profilometry, hardness tests, scanning electron microscopy, and potentiodynamic polarization techniques were used to analyze the structure, thickness, adhesion, microstructure, and corrosion resistance of coated samples, respectively. Results showed that the (111) crystalline orientation dominated in all coatings. Williamson-Hall technique revealed that the crystallite size of ZrN films decreased from 73 to 20 nm with increasing F(N2), and compressive microstrain increased from 0.004 to 0.030. Film thicknesses were inversely correlated with N2 amount and significantly decreased from 1.7 to 0.8 µm. The maximum d P/d r ratio, a dependent factor of adhesion, was 0.04 kg/cm for the film deposited under the F(N2) value of 0.5. The corrosion potential of coated samples was not significantly different from that of uncoated AZ91. Under the F(N2) value of 0.6, corrosion current density slightly decreased from 14 to 9.7 µA/cm2 and significantly increased to 13.5 µA/cm2. Results indicated that ZrN film deposited under the F(N2) value of 0.5 showed high adhesion and corrosion resistance.

  1. Preparation and characterization of nanocrystalline ITO thin films on glass and clay substrates by ion-beam sputter deposition method

    International Nuclear Information System (INIS)

    Venkatachalam, S.; Nanjo, H.; Kawasaki, K.; Wakui, Y.; Hayashi, H.; Ebina, T.

    2011-01-01

    Nanocrystalline indium tin oxide (ITO) thin films were prepared on clay-1 (Clay-TPP-LP-SA), clay-2 (Clay-TPP-SA) and glass substrates using ion-beam sputter deposition method. X-ray diffraction (XRD) patterns showed that the as-deposited ITO films on both clay-1 and clay-2 substrates were a mixture of amorphous and polycrystalline. But the as-deposited ITO films on glass substrates were polycrystalline. The surface morphologies of as-deposited ITO/glass has smooth surface; in contrast, ITO/clay-1 has rough surface. The surface roughnesses of ITO thin films on glass and clay-1 substrate were calculated as 4.3 and 83 nm, respectively. From the AFM and SEM analyses, the particle sizes of nanocrystalline ITO for a film thickness of 712 nm were calculated as 19.5 and 20 nm, respectively. Optical study showed that the optical transmittance of ITO/clay-2 was higher than that of ITO/clay-1. The sheet resistances of as-deposited ITO/clay-1 and ITO/clay-2 were calculated as 76.0 and 63.0 Ω/□, respectively. The figure of merit value for as-deposited ITO/clay-2 (12.70 x 10 -3 /Ω) was also higher than that of ITO/clay-1 (9.6 x 10 -3 /Ω), respectively. The flexibilities of ITO/clay-1 and ITO/clay-2 were evaluated as 13 and 12 mm, respectively. However, the ITO-coated clay-2 substrate showed much better optical and electrical properties as well as flexibility as compared to clay-1.

  2. Depth profile investigation of the incorporated iron atoms during Kr{sup +} ion beam sputtering on Si (001)

    Energy Technology Data Exchange (ETDEWEB)

    Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de [Solid State Physics, University of Siegen, D-57068 Siegen (Germany); Arezki, B.; Biermanns, A. [Solid State Physics, University of Siegen, D-57068 Siegen (Germany); Cornejo, M.; Hirsch, D. [Leibniz-Institut für Oberflächenmodifizierung e. V. (IOM), Permoserstraße 15, D-04318 Leipzig (Germany); Lützenkirchen-Hecht, D. [Abteilung Physik, Bergische Universität Wuppertal, D-42097 Wuppertal (Germany); Frost, F. [Leibniz-Institut für Oberflächenmodifizierung e. V. (IOM), Permoserstraße 15, D-04318 Leipzig (Germany); Pietsch, U. [Solid State Physics, University of Siegen, D-57068 Siegen (Germany)

    2013-01-01

    We investigate the incorporation of iron atoms during nano-patterning of Si surfaces induced by 2 keV Kr{sup +} ion beam erosion under an off-normal incidence angle of 15°. Considering the low penetration depth of the ions, we have used X-ray reflectivity (XRR) and X-ray absorption near edge spectroscopy (XANES) under grazing-incidence angles in order to determine the depth profile and phase composition of the incorporated iron atoms in the near surface region, complemented by secondary ion mass spectrometry and atomic force microscopy. XRR analysis shows the accumulation of metallic atoms within a near surface layer of a few nanometer thickness. We verify that surface pattern formation takes place only when the co-sputtered Fe concentration exceeds a certain limit. For high Fe concentration, the ripple formation is accompanied by the enhancement of Fe close to the surface, whereas no Fe enhancement is found for low Fe concentration at samples with smooth surfaces. Modeling of the measured XANES spectra reveals the appearance of different silicide phases with decreasing Fe content from the top towards the volume. - Highlights: ► We investigate the incorporation of iron atoms during nano-patterning of Si surfaces. ► Pattern formation occurs when the areal density of Fe exceeds a certain threshold. ► X-ray reflectivity shows a layering at near surface due to incorporated Fe atoms. ► It is shown that the patterning is accompanied with the appearance of Fe-rich silicide.

  3. 125 MeV Si 9+ ion irradiation of calcium phosphate thin film coated by rf-magnetron sputtering technique

    Science.gov (United States)

    Elayaraja, K.; Joshy, M. I. Ahymah; Suganthi, R. V.; Kalkura, S. Narayana; Palanichamy, M.; Ashok, M.; Sivakumar, V. V.; Kulriya, P. K.; Sulania, I.; Kanjilal, D.; Asokan, K.

    2011-01-01

    Titanium substrate was coated with hydroxyapatite by radiofrequency magnetron sputtering (rf-magnetron sputtering) technique and subjected to swift heavy ion (SHI) irradiation of 125 MeV with Si 9+ at fluences of 1 × 10 10, 1 × 10 11 and 1 × 10 12 ions/cm 2. The glancing incidence X-ray diffraction (GIXRD) analysis confirmed the HAp phase of the irradiated film. There was a considerable decrease in crystallinity and particle size after irradiation. In addition, DRS-UV reflectance spectra revealed a decrease in optical band gap ( Eg) from 5.2 to 4.6 eV. Wettability of biocompatible materials plays an important role in biological cells proliferation for tissue engineering, drug delivery, gene transfer and bone growth. HAp thin films irradiated with 1 × 10 11 ions/cm 2 fluence showed significant increase in wettability. While the SHI irradiated samples exhibited enhanced bioactivity, there was no significant variation in cell viability. Surface roughness, pores and average particle size were analyzed by atomic force microscopy (AFM).

  4. Applying field mapping refractive beam shapers to improve holographic techniques

    Science.gov (United States)

    Laskin, Alexander; Williams, Gavin; McWilliam, Richard; Laskin, Vadim

    2012-03-01

    Performance of various holographic techniques can be essentially improved by homogenizing the intensity profile of the laser beam with using beam shaping optics, for example, the achromatic field mapping refractive beam shapers like πShaper. The operational principle of these devices presumes transformation of laser beam intensity from Gaussian to flattop one with high flatness of output wavefront, saving of beam consistency, providing collimated output beam of low divergence, high transmittance, extended depth of field, negligible residual wave aberration, and achromatic design provides capability to work with several laser sources with different wavelengths simultaneously. Applying of these beam shapers brings serious benefits to the Spatial Light Modulator based techniques like Computer Generated Holography or Dot-Matrix mastering of security holograms since uniform illumination of an SLM allows simplifying mathematical calculations and increasing predictability and reliability of the imaging results. Another example is multicolour Denisyuk holography when the achromatic πShaper provides uniform illumination of a field at various wavelengths simultaneously. This paper will describe some design basics of the field mapping refractive beam shapers and optical layouts of their applying in holographic systems. Examples of real implementations and experimental results will be presented as well.

  5. High energy (MeV) ion beam modifications of sputtered MoS2 coatings on sapphire

    International Nuclear Information System (INIS)

    Bhattacharya, R.S.; Rai, A.K.; Erdemir, A.

    1991-01-01

    The present article reports on the results of our investigations of high-energy (MeV) ion irradiation on the microstructural and tribological properties of dc magnetron sputtered MoS 2 films. Films of thicknesses 500-7500 A were deposited on NaCl, Si and sapphire substrates and subsequently ion irradiated by 2 MeV Ag + ions at a dose of 5x10 15 cm -2 . Scanning and transmission electron microscopy. Rutherford backscattering and X-ray diffraction techniques were utilized to study the structural, morphological and compositional changes of the film due to ion irradiation. The friction coefficient and sliding life were determined by pin-on-disc tests. Both as-deposited and ion-irradiated films were found to be amorphous having a stoichiometry of MoS 1.8 . A low friction coefficient in the range 0.03-0.04 was measured for both as-deposited and ion-irradiated films. However, the sliding life of ion-irradiated film was found to increase more than tenfold compared to as-deposited films indicating improved bonding at the interface. (orig.)

  6. A technique for aligning sextupole systems using beam optics

    International Nuclear Information System (INIS)

    Chao, Yu-Chiu.

    1992-03-01

    A technique for beam based alignment of sextupole system is developed exploiting the enhancement effect of orbit differences by the sextupoles. This technique can in principle be applied to sextupole or sextupole strings with controlled orbit pattern and BPM configurations. This paper will discuss the theoretical basis, special optimization considerations and expected accuracy. Application to the SLC final focus is also discussed

  7. Beam dynamics in rf guns and emittance correction techniques

    International Nuclear Information System (INIS)

    Serafini, L.

    1994-01-01

    In this paper we present a general review of beam dynamics in a laser-driven rf gun. The peculiarity of such an accelerating structure versus other conventional multi-cell linac structures is underlined on the basis of the Panofsky-Wenzel theorem, which is found to give a theoretical background for the well known Kim's model. A basic explanation for some proposed methods to correct rf induced emittance growth is also derived from the theorem. We also present three emittance correction techniques for the recovery of space-charge induced emittance growth, namely the optimum distributed disk-like bunch technique, the use of rf spatial harmonics to correct spherical aberration induced by space charge forces and the technique of emittance filtering by clipping the electron beam. The expected performances regarding the beam quality achievable with different techniques, as predicted by scaling laws and simulations, are analyzed, and, where available, compared to experimental results. (orig.)

  8. 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.

  9. Improved beam-energy calibration technique for heavy ion accelerators

    International Nuclear Information System (INIS)

    Ferrero, A.M.J.; Garcia, A.; Gil, Salvador

    1989-01-01

    A simple technique for beam energy calibration of heavy-ion accelerators is presented. A thin hydrogenous target was bombarded with 12 C and 19 F, and the energies of the protons knocked out, elastically were measured at several angles using two detectors placed at equal angles on opposite sides of the beam. The use of these two detectors cancels the largest errors due to uncertainties in the angle and position at which the beam hits the target. An application of this energy calibration method to an electrostatic accelerator is described and the calibration constant of the analyzing magnet was obtained with an estimated error of 0.4 (Author) [es

  10. Magnetically scanned proton therapy beams: rationales and techniques

    International Nuclear Information System (INIS)

    Jones, D.T.L.; Schreuder, A.N.

    2000-01-01

    Perhaps the most important advantages of beam scanning systems for proton therapy in comparison with conventional passive beam spreading systems are: (1) Intensity modulation and inverse planning are possible. (2) There is negligible reduction in the range of the beam. (3) Integral dose is reduced as dose conformation to the proximal edge of the lesion is possible. (4) In principle no field-specific modifying devices are required. (5) There is less activation of the surroundings. (6) Scanning systems axe almost infinitely flexible. The main disadvantages include: (1) Scanning systems are more complicated and therefore potentially less reliable and more dangerous. (2) The development of such systems is more demanding in terms of cost, time and manpower. (3) More stable beams are required. (4) Dose and beam position monitoring are more difficult. (5) The problems associated with patient and organ movement axe more severe. There are several techniques which can be used for scanning. For lateral beam spreading, circular scanning (wobbling) or linear scanning can be done. In the latter case the beam can be scanned continuously or in a discrete fashion (spot scanning). Another possibility is to undertake the fastest scan in one dimension (strip scanning) and translate the patient or the scanning magnet in the other dimension. Depth variation is achieved by interposing degraders in the beam (cyclotrons) or by changing the beam energy (synchrotrons). The aim of beam scanning is to deliver a predetermined dose at any point in the body. Special safety precautions must be taken because of the high instantaneous dose rates. The beam position and the dose delivered at each point must be accurately and redundantly determined. (author)

  11. Techniques for intense-proton-beam profile measurements

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.

    1998-01-01

    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 + cw beam to 1.7 GeV and the SNS linac is planned to accelerate a 1- to 4-mA-average, H - , 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

  12. Nanostructured hydroxyapatite/TiO2 composite coating applied to commercially pure titanium by a co-sputtering technique

    International Nuclear Information System (INIS)

    Lee, Baek-Hee; Koshizaki, Naoto

    2008-01-01

    We demonstrate an approach for the coating of nanostructured hydroxyapatite(HAP)/TiO 2 composite on commercially pure Ti (CP-Ti) by a co-sputtering process. HAP/TiO 2 composite film was obtained by controlling the processing pressure. It was observed that decomposition of HAP into CaO was easily induced during sputtering at 0.53 Pa, a typical sputtering condition for film deposition. However, HAP/TiO 2 composite film was obtained with the sputtering pressure of 2.67 Pa. The Ca/P ratio was nearly maintained at 1.66 by sputter deposition at 2.67 Pa. We further confirmed by analysis of plasma spectral emission that the variation of the hydroxyl (OH) radical present was due to the Ar pressure during sputtering. It has been shown that HAP coatings are dependent on the processing pressure, which the hydroxyl radical requires in order to create HAP

  13. Field emission from ZnS nanorods synthesized by radio frequency magnetron sputtering technique

    Science.gov (United States)

    Ghosh, P. K.; Maiti, U. N.; Jana, S.; Chattopadhyay, K. K.

    2006-11-01

    The field emission property of zinc sulphides nanorods synthesized in the thin film form on Si substrates has been studied. It is seen that ZnS nanorod thin films showed good field emission properties with a low-macroscopic turn-on field (2.9-6.3 V/μm). ZnS nanorods were synthesized by using radio frequency magnetron sputtering of a polycrystalline prefabricated ZnS target at a relatively higher pressure (10 -1 mbar) and at a lower substrate temperature (233-273 K) without using any catalyst. Transmission electron microscopic image showed the formation of ZnS nanorods with high aspect ratio (>60). The field emission data were analysed using Fowler-Nordhiem theory and the nearly straight-line nature of the F-N plots confirmed cold field emission of electrons. It was also found that the turn-on field decreased with the decrease of nanorod's diameters. The optical properties of the ZnS nanorods were also studied. From the measurements of transmittance of the films deposited on glass substrates, the direct allowed bandgap values have been calculated and they were in the range 3.83-4.03 eV. The thickness of the films was ˜600 nm.

  14. Stress, microstructure and evolution under ion irradiation in thin films grown by ion beam sputtering: modelling and application to interfacial effects in metallic multilayers

    International Nuclear Information System (INIS)

    Debelle, A.

    2006-09-01

    We have investigated the formation of the interfacial chemical mixing in Mo/Ni multilayers, and particularly the influence of ballistic effects during the growth. For this purpose, hetero-epitaxial b.c.c./f.c.c. Mo(110)/Ni(111) multilayers were grown by two deposition methods: thermal evaporation and direct ion beam sputtering. As a preliminary, an accurate description of the stress state in pure sputtered Mo thin films was required. Microstructural and stress state analyses were essentially carried out by X-ray diffraction, and ion irradiation was used as a powerful tool to control the stress level. We showed that thermal evaporated thin films exhibit a weak tensile growth stress (∼ 0.6 GPa) that can be accounted for by the grain boundary relaxation model, whereas sputtered thin films develop large compressive growth stress (- 2 to - 4 GPa). This latter results from the bombardment of the growing film by the energetic particles involved during the sputtering process (atomic peening phenomenon), which induces the formation of defects in the layers, generating volume distortions. We thus developed a stress model that includes a hydrostatic stress component to account for these volume strains. This model allowed us to determine the 'unstressed and free of defects lattice parameter' a 0 , solely linked to chemical effects. For epitaxial Mo layers, it was possible to separate coherency stress from growth stress due to their distinct kinetic evolution during ion irradiation. Therefore, the stress analysis enabled us to determine the a 0 values in Mo sub-layers of Mo/Ni superlattices. A tendency to the formation of an interfacial alloy is observed independently of the growth conditions, which suggests that thermodynamic forces favour the exchange mechanism. However, the extent of the intermixing effect is clearly enhanced by ballistic effects. (author)

  15. Novel uses of a wide beam saddle field ion source for producing targets used in nuclear physics experiments at the Argonne National Laboratory ATLAS facility

    International Nuclear Information System (INIS)

    Greene, J.P.; Thomas, G.E.

    1996-01-01

    The wide beam ion sputter source has several unique characteristics which make it very useful for producing, reducing the thickness or cleaning the surface of targets needed for nuclear physics experiments. A discussion of these techniques as well as the sputter source characteristics will be given. Sputter yields obtained utilizing the source are presented for a variety of materials common to nuclear target production

  16. Application of the Ta liner technique to produce Ca beams at INFN-Legnaro National Laboratories (INFN-LNL)

    Energy Technology Data Exchange (ETDEWEB)

    Galatà, A., E-mail: alessio.galata@lnl.infn.it; Sattin, M.; Manzolaro, M.; Martini, D.; Facco, A. [INFN-Legnaro National Laboratories, Legnaro (Pd) (Italy); Tinschert, K.; Spaedtke, P.; Lang, R. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Kulevoy, T. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation)

    2014-02-15

    The ECR ion sources are able to produce a wide variety of highly charged metallic ion beams thanks to the development of different techniques (ovens, sputtering, direct insertion, metal ions from volatile compounds (MIVOC)). In the case of the ovens, the sticking of the hot vapors on the surface of the plasma chamber leads to high material consumption rates. For elements like Ca, a tantalum liner inserted inside the chamber can be used to limit this phenomenon. The modeling of temperature distribution inside the chamber with and without the liner was carried out with COMSOL-multiphysics code. Results of simulation and the comparison with experiments performed at INFN-Legnaro National Laboratories with Ca beams are discussed.

  17. Mechanical properties of micro-sized copper bending beams machined by the focused ion beam technique

    International Nuclear Information System (INIS)

    Motz, C.; Schoeberl, T.; Pippan, R.

    2005-01-01

    Micro-sized bending beams with thicknesses, t, from 7.5 down to 1.0 μm were fabricated with the focused ion beam technique from a copper single crystal with an {1 1 1} orientation. The beams were loaded with a nano-indenter and the force vs. displacement curves were recorded. A strong size effect was found where the flow stress reaches almost 1 GPa for the thinnest beams. A common strain gradient plasticity approach was used to explain the size effect. However, the strong t -1.14 dependence of the flow stress could not be explained by this model. Additionally, the combination of two other dislocation mechanisms is discussed: the limitation of available dislocation sources and a dislocation pile-up at the beam centre. The contribution of the pile-up stress to the flow stress gives a t -1 dependence, which is in good agreement with the experimental results

  18. Photocatalytic efficiency of reusable ZnO thin films deposited by sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Ahumada-Lazo, R.; Torres-Martínez, L.M. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Civil, Departamento de Ecomateriales y Energía, Av. Universidad S/N Ciudad Universitaria, San Nicolás de los Garza, Nuevo León C.P. 66450, México (Mexico); Ruíz-Gómez, M.A. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Civil, Departamento de Ecomateriales y Energía, Av. Universidad S/N Ciudad Universitaria, San Nicolás de los Garza, Nuevo León C.P. 66450, México (Mexico); Departmento de Física Aplicada, CINVESTAV-IPN, Antigua Carretera a Progreso km 6, Mérida, Yucatán 97310, México (Mexico); Vega-Becerra, O.E. [Centro de Investigación en Materiales Avanzados S.C, Alianza norte 202, Parque de Investigación e Innovación Tecnológica, C.P. 66600 Apodaca Nuevo León, México (Mexico); and others

    2014-12-15

    Graphical abstract: - Highlights: • Decolorization of Orange G dye using highly c-axis-oriented ZnO thin films. • The flake-shaped film shows superior and stable photoactivity at a wide range of pH. • The highest photodecolorization was achieved at pH of 7. • The exposure of (101) and (100) facets enhanced the photoactivity. • ZnO thin films exhibit a promising performance as recyclable photocatalysts. - Abstract: The photocatalytic activity of ZnO thin films with different physicochemical characteristics deposited by RF magnetron sputtering on glass substrate was tested for the decolorization of orange G dye aqueous solution (OG). The crystalline phase, surface morphology, surface roughness and the optical properties of these ZnO films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV–visible spectroscopy (UV–Vis), respectively. The dye photodecolorization process was studied at acid, neutral and basic pH media under UV irradiation of 365 nm. Results showed that ZnO films grow with an orientation along the c-axis of the substrate and exhibit a wurtzite crystal structure with a (002) preferential crystalline orientation. A clear relationship between surface morphology and photocatalytic activity was observed for ZnO films. Additionally, the recycling photocatalytic abilities of the films were also evaluated. A promising photocatalytic performance has been found with a very low variation of the decolorization degree after five consecutive cycles at a wide range of pH media.

  19. Photocatalytic efficiency of reusable ZnO thin films deposited by sputtering technique

    International Nuclear Information System (INIS)

    Ahumada-Lazo, R.; Torres-Martínez, L.M.; Ruíz-Gómez, M.A.; Vega-Becerra, O.E.

    2014-01-01

    Graphical abstract: - Highlights: • Decolorization of Orange G dye using highly c-axis-oriented ZnO thin films. • The flake-shaped film shows superior and stable photoactivity at a wide range of pH. • The highest photodecolorization was achieved at pH of 7. • The exposure of (101) and (100) facets enhanced the photoactivity. • ZnO thin films exhibit a promising performance as recyclable photocatalysts. - Abstract: The photocatalytic activity of ZnO thin films with different physicochemical characteristics deposited by RF magnetron sputtering on glass substrate was tested for the decolorization of orange G dye aqueous solution (OG). The crystalline phase, surface morphology, surface roughness and the optical properties of these ZnO films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV–visible spectroscopy (UV–Vis), respectively. The dye photodecolorization process was studied at acid, neutral and basic pH media under UV irradiation of 365 nm. Results showed that ZnO films grow with an orientation along the c-axis of the substrate and exhibit a wurtzite crystal structure with a (002) preferential crystalline orientation. A clear relationship between surface morphology and photocatalytic activity was observed for ZnO films. Additionally, the recycling photocatalytic abilities of the films were also evaluated. A promising photocatalytic performance has been found with a very low variation of the decolorization degree after five consecutive cycles at a wide range of pH media

  20. The application of Lie algebra techniques to beam transport design

    International Nuclear Information System (INIS)

    Irwin, J.

    1990-01-01

    Using a final focus system for high-energy linear colliders as an example of a beam transport system, we illustrate for each element, and for the interplay of elements, the connection of Lie algebra techniques with usual optical analysis methods. Our analysis describes, through fourth order, the calculation and compensation of all important aberrations. (orig.)

  1. Effects of deposition and post-annealing conditions on electrical properties and thermal stability of TiAlN films by ion beam sputter deposition

    International Nuclear Information System (INIS)

    Lee, S.-Y.; Wang, S.-C.; Chen, J.-S.; Huang, J.-L.

    2006-01-01

    TiAlN films were deposited by ion beam sputter deposition (IBSD) using a Ti-Al (90/10) alloy target in a nitrogen atmosphere on thermal oxidized Si wafers. Effects of ion beam voltage, substrate temperature (T s ) and post-annealing conditions on electrical properties and oxidation resistance of TiAlN films were studied. According to the experimental results, the proper kinetic energy provided good crystallinity and a dense structure of the films. Because of their better crystallinity and predomination of (200) planes, TiAlN films deposited with 900 V at low T s (50 deg. C) have shown lower resistivity than those at high T s (250 deg. C). They also showed better oxidation resistance. If the beam voltage was too high, it caused some damage to the film surfaces, which caused poor oxidation resistance of films. When sufficient kinetic energy was provided by the beam voltage, the mobility of adatoms was too high due to their extra thermal energy, thus reducing the crystallinity and structure density of the films. A beam voltage of 900 V and a substrate temperature of 50 deg. C were the optimum deposition conditions used in this research. They provided good oxidation resistance and low electrical resistivity for IBSD TiAlN films

  2. Ion beam techniques for analyzing polymers irradiated by ions

    International Nuclear Information System (INIS)

    Rickards, J.; Zironi, E.P.; Andrade, E.; Dominguez, B.

    1992-01-01

    In the study of the effects of ion beam irradiation of polymers very large doses can be administered in short times. Thousands of MGy can be produced in a small volume of a sample in a few minutes by bombarding with typical ion beam currents. For instance, in an experiment done to observe the effects of 750 keV proton irradiation PVC, using a collimator of 1 mm diameter, 1 μC of charge integration deposits a dose of 50 MGy. The use of ion beams also opens up the possibility of using the same beam for irradiation and for analysis of the effects, using the well known ion beam analysis techniques. PIXE allows the measurement of chlorine in PVC. Polymers containing fluorine can be measured with the resonant nuclear reaction (RNR) technique, which is specific only to certain elements. The amount of hydrogen in the sample and its profile can be obtained using energy recoil detection analysis (ERDA); carbon, oxygen, and nitrogen can be measured and profiled using Rutherford backscattering (RBS) and also using the (d,p) and (d, α) nuclear reactions (NR). Loss of mass is one effect that can be studied using these techniques. It was studied in two different polymers, PVC and CR-39, in order to determine carbon buildup during ion irradiation. It was concluded that carbon builds up following different mechanisms in these two materials, due to the different possibilities of forming volatile compounds. It is also suggested that CR-39 should be a good material for ion beam lithography. (author)

  3. Synthesis and characterization of porous crystalline SiC thin films prepared by radio frequency reactive magnetron sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Qamar, Afzaal, E-mail: afzaalqamar@gmail.com [Department of Physics and Applied Mathematics, PIEAS, Nilore, Islamabad, Punjab 42600 (Pakistan); Mahmood, Arshad [National Institute of Laser and Optronics, Nilore, Islamabad (Pakistan); Sarwar, Tuba; Ahmed, Nadeem [Department of Physics and Applied Mathematics, PIEAS, Nilore, Islamabad, Punjab 42600 (Pakistan)

    2011-05-15

    Hexagonal SiC thin films have been deposited using radio frequency reactive magnetron sputtering technique by varying the substrate temperature and other deposition conditions. Prior to deposition surface modification of the substrate Si(1 0 0) played an important role in deposition of the hexagonal SiC structure. The effect of substrate temperature during deposition on structure, composition and surface morphology of the SiC films has been analyzed using atomic force microscopy, Fourier transform infrared spectroscopy and spectroscopic ellipsometry. X-ray diffraction in conventional {theta}-2{theta} mode and omega scan mode revealed that the deposited films were crystalline having 8H-SiC structure and crystallinity improved with increase of deposition temperature. The bonding order and Si-C composition within the films showed improvement with the increase of deposition temperature. The surface of thin films grew in the shape of globes and columns depending upon deposition temperature. The optical properties also showed improvement with increase of deposition temperature and the results obtained by ellipsometry reinforced the results of other techniques.

  4. Radioactive ion beams and techniques for solid state research

    International Nuclear Information System (INIS)

    Correia, J.G.

    1998-01-01

    In this paper we review the most recent and new applications of solid state characterization techniques using radioactive ion beams. For such type ofresearch, high yields of chemically clean ion beams of radioactive isotopesare needed which are provided by the on-line coupling of high resolution isotope separators to particle accelerators, such as the isotope separator on-line (ISOLDE) facility at CERN. These new experiments are performed by an increasing number of solid state groups. They combine nuclear spectroscopic techniques such as Moessbauer, perturbed angular correlations (PAC) and emission channeling with the traditional non-radioactive techniques liked deep level transient spectroscopy (DLTS) and Hall effect measurements. Recently isotopes of elements, not available before, were successfully used in new PAC experiments, and the first photoluminescence (PL) measurements, where the element transmutation plays the essential role on the PL peak identification, have been performed. The scope of applications of radioactive ion beams for research in solid state physics will be enlarged in the near future, with the installation at ISOLDE of a post-accelerator device providing radioactive beams with energies ranging from a few keV up to a few MeV. (orig.)

  5. Sputtered catalysts

    International Nuclear Information System (INIS)

    Tyerman, W.J.R.

    1978-01-01

    A method is described for preparing a supported catalyst by a sputtering process. A material that is catalytic, or which is a component of a catalytic system, is sputtered on to the surface of refractory oxide particles that are compatible with the sputtered material and the sputtered particles are consolidated into aggregate form. The oxide particles before sputtering should have a diameter in the range 1000A to 50μ and a porosity less than 0.4 ml/g, and may comprise MgO, Al 2 O 3 or SiO 2 or mixtures of these oxides, including hydraulic cement. The particles may possess catalytic activity by themselves or in combination with the catalytic material deposited on them. Sputtering may be effected epitaxially and consolidation may be effected by compaction pelleting, extrusion or spray drying of a slurry. Examples of the use of such catalysts are given. (U.K.)

  6. Textured surface structures formed using new techniques on transparent conducting Al-doped zinc oxide films prepared by magnetron sputtering

    International Nuclear Information System (INIS)

    Minami, Tadatsugu; Miyata, Toshihiro; Uozaki, Ryousuke; Sai, Hitoshi; Koida, Takashi

    2016-01-01

    Surface-textured Al-doped ZnO (AZO) films formed using two new techniques based on magnetron sputtering deposition were developed by optimizing the light scattering properties to be suitable for transparent electrode applications in thin-film silicon solar cells. Scrambled egg-like surface-textured AZO films were prepared using a new texture formation technique that post-etched pyramidal surface-textured AZO films prepared under deposition conditions suppressing c-axis orientation. In addition, double surface-textured AZO films were prepared using another new texture formation technique that completely removed, by post-etching, the pyramidal surface-textured AZO films previously prepared onto the initially deposited low resistivity AZO films; simultaneously, the surface of the low resistivity films was slightly etched. However, the obtained very high haze value in the range from the near ultraviolet to visible light in the scrambled egg-like surface-textured AZO films did not contribute significantly to the obtainable photovoltaic properties in the solar cells fabricated using the films. Significant light scattering properties as well as a low sheet resistance could be achieved in the double surface-textured AZO films. In addition, a significant improvement of external quantum efficiency in the range from the near ultraviolet to visible light was achieved in superstrate-type n-i-p μc-Si:H solar cells fabricated using a double surface-textured AZO film prepared under optimized conditions as the transparent electrode. - Highlights: • Double surface-textured AZO films prepared using a new texture formation technique • Extensive light scattering properties with low sheet resistance achieved in the double surface-textured AZO films • Improved external quantum efficiency of μc-Si:H solar cells using a double surface-textured AZO film

  7. Textured surface structures formed using new techniques on transparent conducting Al-doped zinc oxide films prepared by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Minami, Tadatsugu [Optoelectronic Device System R& D Center, Kanazawa Institute of Technology, Nonoichi, Ishikawa 921-8501 (Japan); Miyata, Toshihiro, E-mail: tmiyata@neptune.kanazawa-it.ac.jp [Optoelectronic Device System R& D Center, Kanazawa Institute of Technology, Nonoichi, Ishikawa 921-8501 (Japan); Uozaki, Ryousuke [Optoelectronic Device System R& D Center, Kanazawa Institute of Technology, Nonoichi, Ishikawa 921-8501 (Japan); Sai, Hitoshi; Koida, Takashi [Research Center for Photovoltaics, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan)

    2016-09-01

    Surface-textured Al-doped ZnO (AZO) films formed using two new techniques based on magnetron sputtering deposition were developed by optimizing the light scattering properties to be suitable for transparent electrode applications in thin-film silicon solar cells. Scrambled egg-like surface-textured AZO films were prepared using a new texture formation technique that post-etched pyramidal surface-textured AZO films prepared under deposition conditions suppressing c-axis orientation. In addition, double surface-textured AZO films were prepared using another new texture formation technique that completely removed, by post-etching, the pyramidal surface-textured AZO films previously prepared onto the initially deposited low resistivity AZO films; simultaneously, the surface of the low resistivity films was slightly etched. However, the obtained very high haze value in the range from the near ultraviolet to visible light in the scrambled egg-like surface-textured AZO films did not contribute significantly to the obtainable photovoltaic properties in the solar cells fabricated using the films. Significant light scattering properties as well as a low sheet resistance could be achieved in the double surface-textured AZO films. In addition, a significant improvement of external quantum efficiency in the range from the near ultraviolet to visible light was achieved in superstrate-type n-i-p μc-Si:H solar cells fabricated using a double surface-textured AZO film prepared under optimized conditions as the transparent electrode. - Highlights: • Double surface-textured AZO films prepared using a new texture formation technique • Extensive light scattering properties with low sheet resistance achieved in the double surface-textured AZO films • Improved external quantum efficiency of μc-Si:H solar cells using a double surface-textured AZO film.

  8. Source reconstruction using phase space beam summation technique

    International Nuclear Information System (INIS)

    Graubart, Gideon.

    1990-10-01

    In this work, the phase-space beam summation technique (PSBS), is applied to back propagation and inverse source problems. The PSBS expresses the field as a superposition of shifted and tilted beams. This phase space spectrum of beams is matched to the source distribution via an amplitude function which expresses the local spectrum of the source function in terms of a local Fourier transform. In this work, the emphasis is on the phase space processing of the data, on the information content of this data and on the back propagation scheme. More work is still required to combine this back propagation approach in a full, multi experiment inverse scattering scheme. It is shown that the phase space distribution of the data, computed via the local spectrum transform, is localized along lines that define the local arrival direction of the wave data. We explore how the choice of the beam width affects the compactification of this distribution, and derive criteria for choosing a window that optimizes this distribution. It should be emphasized that compact distribution implies fewer beams in the back propagation scheme and therefore higher numerical efficiency and better physical insight. Furthermore it is shown how the local information property of the phase space representation can be used to improve the performance of this simple back propagation problem, in particular with regard to axial resolution; the distance to the source can be determined by back propagating only the large angle phase space beams that focus on the source. The information concerning transverse distribution of the source, on the other hand, is contained in the axial phase space region and can therefore be determined by the corresponding back propagating beams. Because of the global nature of the plane waves propagators the conventional plane wave back propagation scheme does not have the same 'focusing' property, and therefore suffers from lack of information localization and axial resolution. The

  9. Low-temperature deposition of ZnO thin films on PET and glass substrates by DC-sputtering technique

    International Nuclear Information System (INIS)

    Banerjee, A.N.; Ghosh, C.K.; Chattopadhyay, K.K.; Minoura, Hideki; Sarkar, Ajay K.; Akiba, Atsuya; Kamiya, Atsushi; Endo, Tamio

    2006-01-01

    The structural, optical and electrical properties of ZnO thin films (260 - 490 nm thick) deposited by direct-current sputtering technique, at a relatively low-substrate temperature (363 K), onto polyethylene terephthalate and glass substrates have been investigated. X-ray diffraction patterns confirm the proper phase formation of the material. Optical transmittance data show high transparency (80% to more than 98%) of the films in the visible portion of solar radiation. Slight variation in the transparency of the films is observed with a variation in the deposition time. Electrical characterizations show the room-temperature conductivity of the films deposited onto polyethylene terephthalate substrates for 4 and 5 h around 0.05 and 0.25 S cm -1 , respectively. On the other hand, for the films deposited on glass substrates, these values are 8.5 and 9.6 S cm -1 for similar variation in the deposition time. Room-temperature conductivity of the ZnO films deposited on glass substrates is at least two orders of magnitude higher than that of ZnO films deposited onto polyethylene terephthalate substrates under identical conditions. Hall-measurements show the maximum carrier concentration of the films on PET and glass substrate around 2.8 x 10 16 and 3.1 x 10 2 cm -3 , respectively. This report will provide newer applications of ZnO thin films in flexible display technology

  10. Development of high-polarization Fe/Ge neutron polarizing supermirror: Possibility of fine-tuning of scattering length density in ion beam sputtering

    Science.gov (United States)

    Maruyama, R.; Yamazaki, D.; Akutsu, K.; Hanashima, T.; Miyata, N.; Aoki, H.; Takeda, M.; Soyama, K.

    2018-04-01

    The multilayer structure of Fe/Si and Fe/Ge systems fabricated by ion beam sputtering (IBS) was investigated using X-ray and polarized neutron reflectivity measurements and scanning transmission electron microscopy with energy-dispersive X-ray analysis. The obtained result revealed that the incorporation of sputtering gas particles (Ar) in the Ge layer gives rise to a marked reduction in the neutron scattering length density (SLD) and contributes to the SLD contrast between the Fe and Ge layers almost vanishing for spin-down neutrons. Bundesmann et al. (2015) have shown that the implantation of primary Ar ions backscattered at the target is responsible for the incorporation of Ar particles and that the fraction increases with increasing ion incidence angle and increasing polar emission angle. This leads to a possibility of fine-tuning of the SLD for the IBS, which is required to realize a high polarization efficiency of a neutron polarizing supermirror. Fe/Ge polarizing supermirror with m = 5 fabricated under the same condition showed a spin-up reflectivity of 0.70 at the critical momentum transfer. The polarization was higher than 0.985 for the qz range where the correction for the polarization inefficiencies of the beamline works properly. The result of the polarized neutron reflectivity measurement suggests that the "magnetically-dead" layers formed at both sides of the Fe layer, together with the SLD contrast, play a critical role in determining the polarization performance of a polarizing supermirror.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    crystal fiber (PCF). Using this technique we fabricate a highly compact fiber-optic Fabry-Pérot (FP) refractive index sensor near the tip of fiber taper, and a highly sensitive in-line temperature sensor in PCF. We also demonstrate the potential of using FIB to selectively fill functional fluid......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...

  12. Carbon thin films deposited by the magnetron sputtering technique using cobalt, copper and nickel as buffer-layers

    International Nuclear Information System (INIS)

    Costa e Silva, Danilo Lopes

    2015-01-01

    In this work, carbon thin films were produced by the magnetron sputtering technique using single crystal substrates of alumina c-plane (0001) and Si (111) and Si (100) substrates, employing Co, Ni and Cu as intermediate films (buffer-layers). The depositions were conducted in three stages, first with cobalt buffer-layers where only after the production of a large number of samples, the depositions using cooper buffer-layers were carried out on Si substrates. Then, depositions were performed with nickel buffer layers using single-crystal alumina substrates. The crystallinity of the carbon films was evaluated by using the technique of Raman spectroscopy and, then, by X-ray diffraction (XRD). The morphological characterization of the films was performed by scanning electron microscopy (SEM and FEG-SEM) and high-resolution transmission electron microscopy (HRTEM). The XRD peaks related to the carbon films were observed only in the results of the samples with cobalt and nickel buffer-layers. The Raman spectroscopy showed that the carbon films with the best degree of crystallinity were the ones produced with Si (111) substrates, for the Cu buffers, and sapphire substrates for the Ni and Co buffers, where the latter resulted in a sample with the best crystallinity of all the ones produced in this work. It was observed that the cobalt has low recovering over the alumina substrates when compared to the nickel. Sorption tests of Ce ions by the carbon films were conducted in two samples and it was observed that the sorption did not occur probably because of the low crystallinity of the carbon films in both samples. (author)

  13. Electrical characterization of sputtered ZnO:Al films with microprobe technique

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Kjær, Daniel; Petersen, Dirch Hjorth

    2014-01-01

    Determination of sheet resistance, carrier density and mobility in transparent conductive films is typically done with the van der Pauw technique, a rather destructive macroscopic method requiring special sample geometry or dedicated sample patterning. In this work a miniaturized non-destructive ......Determination of sheet resistance, carrier density and mobility in transparent conductive films is typically done with the van der Pauw technique, a rather destructive macroscopic method requiring special sample geometry or dedicated sample patterning. In this work a miniaturized non...... obtained in one location the electrical properties are extracted and the resulting measurement errors are below 1% for sheet resistance and 4% for carrier density and Hall mobility. Such a setup eliminates the need for ad-hoc sample geometries and allows line scans along a cleaved edge of the sample...... microscopy (AFM). The most appropriate choice of deposition and post-deposition process parameters is discussed for application of ZnO:Al films as window layers in thin-film chalcogenide solar cells, where film resistivity should be minimized while maintaining a high transmittance in the spectral region...

  14. Low-temperature growth of (2 1-bar 1-bar 0) ZnO nanofilm on NaCl (0 0 1) surface by ion beam sputtering

    International Nuclear Information System (INIS)

    Shen, Jung-Hsiung; Yeh, Sung-Wei; Huang, Hsing-Lu; Gan, Dershin

    2009-01-01

    ZnO nanofilm of the (2 1 -bar 1 -bar 0) surface was prepared by ion beam sputtering deposition. The nanofilm was prepared on NaCl (0 0 1) surface at 200 o C to produce nearly pure (2 1 -bar 1 -bar 0) ZnO texture and the orientation relationship was determined and the interface discussed. Transmission electron microscopy lattice images were used to find the interface formed between ZnO nanocrystals. The ZnO nanocrystals coalesced to form a straight (0 1 -bar 1 -bar 2) interface. The photoluminescence spectrum from the (2 1 -bar 1 -bar 0) ZnO surface showed only a near-band-edge UV emission peak.

  15. Realization of synaptic learning and memory functions in Y2O3 based memristive device fabricated by dual ion beam sputtering

    Science.gov (United States)

    Das, Mangal; Kumar, Amitesh; Singh, Rohit; Than Htay, Myo; Mukherjee, Shaibal

    2018-02-01

    Single synaptic device with inherent learning and memory functions is demonstrated based on a forming-free amorphous Y2O3 (yttria) memristor fabricated by dual ion beam sputtering system. Synaptic functions such as nonlinear transmission characteristics, long-term plasticity, short-term plasticity and ‘learning behavior (LB)’ are achieved using a single synaptic device based on cost-effective metal-insulator-semiconductor (MIS) structure. An ‘LB’ function is demonstrated, for the first time in the literature, for a yttria based memristor, which bears a resemblance to certain memory functions of biological systems. The realization of key synaptic functions in a cost-effective MIS structure would promote much cheaper synapse for artificial neural network.

  16. X-ray photoelectron spectroscopy investigation of ion beam sputtered indium tin oxide films as a function of oxygen pressure during deposition

    International Nuclear Information System (INIS)

    Nelson, A.J.; Aharoni, H.

    1987-01-01

    X-ray photoelectron spectroscopy analysis was performed on ion beam sputter deposited films of indium tin oxide as a function of O 2 partial pressure during deposition. The oxygen partial pressure was varied over the range of 2.5 x 10 -6 --4.0 x 10 -5 Torr. Changes in composition as well as in the deconvoluted In 3d 5 /sub // 2 , Sn 3d 5 /sub // 2 , and O 1s core level spectra were observed and correlated with the variation of the oxygen partial pressure during deposition. Results show that the films become increasingly stoichiometric as P/sub =/ is increased and that the excess oxygen introduced during deposition is bound predominantly to the Sn and has little or no effect on the In--O bonding

  17. Ion source techniques for high-speed processing of material surface by ion beams

    International Nuclear Information System (INIS)

    Ishikawa, Junzo

    1990-01-01

    The present paper discusses some key or candidate techniques for future ion source development and such ion sources developed by the author. Several types of microwave ion sources for producing low charge state ions have been developed in Japan. When a microwave plasma cathode developed by the author is adapted to a Kaufman type ion source, the electron emission currents are found to be 2.5 A for argon gas and 0.5-0.9 A for oxygen gas. An alternative ionization method for metal atoms is strongly required for high-speed processing of material surface by metal-ion beams. Detailed discussion is made of collisional ionization of vaporized atoms, and negative-ion production (secondary negative-ion emission by sputtering). An impregnated electrode type liquid-metal ion source developed by the author, which has a porous tip structure, is described. The negative-ion production efficiency is quite high. The report also presents a neutral and ionized alkaline-metal bombardment type heavy negative-ion source, which consists of a cesium plasma ion source, suppressor, target electrode, negative-ion extraction electrode, and einzel lens. (N.K.)

  18. Identification and roles of nonstoichiometric oxygen in amorphous Ta{sub 2}O{sub 5} thin films deposited by electron beam and sputtering processes

    Energy Technology Data Exchange (ETDEWEB)

    Mannequin, Cedric, E-mail: MANNEQUIN.Cedricromuald@nims.go.jp [International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan); Tsuruoka, Tohru [International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan); Hasegawa, Tsuyoshi [Department of Applied Physics, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Aono, Masakazu [International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan)

    2016-11-01

    Highlights: • A detail study of the composition and morphology of amorphous tantalum oxide films obtained by electron-beam evaporation and radio-frequency sputtering is carried out. • The mechanisms for moisture absorption by tantalum oxides are proposed. • Deposition-dependent high oxygen stoichiometry of the films is revealed. • Formations of dangling bonds, hydroxyls groups and bidendate water bridges are identified to support the moisture absorption. - Abstract: The morphology and composition of tantalum oxide (Ta{sub 2}O{sub 5}) thin films prepared by electron-beam (EB) evaporation and radio-frequency sputtering (SP) were investigated by grazing incidence X-ray diffraction (GIXRD), X-ray reflectometry (XRR), atomic force microscopy, Fourier transformed infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). GIXRD revealed an amorphous nature for both films, and XRR showed that the density of the Ta{sub 2}O{sub 5}-EB films was lower than that of the Ta{sub 2}O{sub 5}-SP films; both films have lower density than the bulk value. A larger amount of molecular water and peroxo species were detected for the Ta{sub 2}O{sub 5}-EB films by FTIR performed in ambient atmosphere. XPS analyses performed in vacuum confirmed the presence of hydroxyl groups, but no trace of chemisorbed molecular water was detected. In addition, a higher oxygen nonstoichiometry (higher O/Ta ratio) was found for the EB films. From these results, we conclude that the oxygen nonstoichiometry of the EB film accounted for its lower density and higher amount of absorbed molecular water. The results also suggest the importance of understanding the dependence of the structural and chemical properties of thin amorphous oxide films on the deposition process.

  19. Growth stress buildup in ion beam sputtered Mo thin films and comparative study of stress relaxation upon thermal annealing or ion irradiation

    International Nuclear Information System (INIS)

    Debelle, A.; Abadias, G.; Michel, A.; Jaouen, C.; Pelosin, V.

    2007-01-01

    In an effort to address the understanding of the origin of growth stress in thin films deposited under very energetic conditions, the authors investigated the stress state and microstructure of Mo thin films grown by ion beam sputtering (IBS) as well as the stress relaxation processes taking place during subsequent thermal annealing or ion irradiation. Different sets of samples were grown by varying the IBS deposition parameters, namely, the energy E 0 and the flux j of the primary ion beam, the target-to-sputtering gas mass ratio M 1 /M 2 as well as film thickness. The strain-stress state was determined by x-ray diffraction using the sin 2 ψ method and data analyzed using an original stress model which enabled them to correlate information at macroscopic (in terms of stress) and microscopic (in terms of defect concentration) levels. Results indicate that these refractory metallic thin films are characterized by a high compressive growth stress (-2.6 to -3.8 GPa), resulting from the creation of a large concentration (up to ∼1.4%) of point or cluster defects, due to the atomic peening mechanism. The M 1 /M 2 mass ratio enables tuning efficiently the mean deposited energy of the condensing atoms; thus, it appears to be the more relevant deposition parameter that allows modifying both the microstructure and the stress level in a significant way. The growth stress comes out to be highly unstable. It can be easily relaxed either by postgrowth thermal annealing or ion irradiation in the hundred keV range at very low dose [<0.1 dpa (displacement per atom)]. It is shown that thermal annealing induces deleterious effects such as oxidation of the film surface, decrease of the film density, and in some cases adhesion loss at the film/substrate interface, while ion irradiation allows controlling the stress level without generating any macroscopic damage

  20. Ion-beam mixed ultra-thin cobalt suicide (CoSi2) films by cobalt sputtering and rapid thermal annealing

    Science.gov (United States)

    Kal, S.; Kasko, I.; Ryssel, H.

    1995-10-01

    The influence of ion-beam mixing on ultra-thin cobalt silicide (CoSi2) formation was investigated by characterizing the ion-beam mixed and unmixed CoSi2 films. A Ge+ ion-implantation through the Co film prior to silicidation causes an interface mixing of the cobalt film with the silicon substrate and results in improved silicide-to-silicon interface roughness. Rapid thermal annealing was used to form Ge+ ion mixed and unmixed thin CoSi2 layer from 10 nm sputter deposited Co film. The silicide films were characterized by secondary neutral mass spectroscopy, x-ray diffraction, tunneling electron microscopy (TEM), Rutherford backscattering, and sheet resistance measurements. The experi-mental results indicate that the final rapid thermal annealing temperature should not exceed 800°C for thin (micrographs of the ion-beam mixed and unmixed CoSi2 films reveals that Ge+ ion mixing (45 keV, 1 × 1015 cm-2) produces homogeneous silicide with smooth silicide-to-silicon interface.

  1. New technique for levitating solid particles using a proton beam

    International Nuclear Information System (INIS)

    Misconi, N.Y.

    1996-01-01

    A new technique for levitating solid particles inside a vacuum chamber is developed using a proton beam. This new technique differs from the classical laser-levitation technique invented by Ashkin in that it does not heat up light-absorbing levitated particles to vaporization. This unique property of the method will make it possible to levitate real interplanetary dust particles in a vacuum chamber and study their spin-up dynamics in a ground-based laboratory. It is found that a flux of protons from a proton gun of ∼ 10 15 cm -2 sec -1 is needed to levitate a 10-mm particle. Confinement of the levitated particle can be achieved by a Z or θ pinch to create a gravity well, or by making the beam profile doughnut in shape. In levitating real interplanetary particles, two spin-up mechanisms can be investigated using this technique: one is the Paddack Effect and the other is a spin-up mechanism by the interaction of F-coronal dust with CMEs (Coronal Mass Ejections). The real interplanetary particles were collected by Brownie and associates (also known as the Brownie Particles) from the earth's upper atmosphere. (author)

  2. Ion Beam Analysis, structure and corrosion studies of nc-TiN/a-Si{sub 3}N{sub 4} nanocomposite coatings deposited by sputtering on AISI 316L

    Energy Technology Data Exchange (ETDEWEB)

    García, J. [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, J. Guadalupe Zuno 48, Los Belenes, Zapopan, Jal. 45101 (Mexico); Canto, C.E. [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, México, D.F. 04510 (Mexico); Flores, M. [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, J. Guadalupe Zuno 48, Los Belenes, Zapopan, Jal. 45101 (Mexico); Andrade, E., E-mail: andrade@fisica.unam.mx [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, México, D.F. 04510 (Mexico); Rodríguez, E.; Jiménez, O. [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, J. Guadalupe Zuno 48, Los Belenes, Zapopan, Jal. 45101 (Mexico); Solis, C.; Lucio, O.G. de [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, México, D.F. 04510 (Mexico); Rocha, M.F. [ESIME-Z, Instituto Politécnico Nacional, ALM Zacatenco, México, D.F. 07738 (Mexico)

    2014-07-15

    In this work, nanocomposite coatings of nc-TiN/a-Si{sub 3}N{sub 4}, were deposited on AISI 316L stainless steel substrate by a DC and RF reactive magnetron co-sputtering technique using an Ar–N{sub 2} plasma. The structure of the coatings was characterized by means of XRD (X-ray Diffraction). The substrate and coating corrosion resistance were evaluated by potentiodynamic polarization using a Ringer solution as electrolyte. Corrosion tests were conducted with the purpose to evaluate the potential of this coating to be used on biomedical alloys. IBA (Ion Beam Analysis) techniques were applied to measure the elemental composition profiles of the films and, XPS (X-ray Photoelectron Spectroscopy) were used as a complementary technique to obtain information about the compounds present in the films. The nanocomposite coatings of nc-TiN/a-Si{sub 3}N{sub 4} show crystalline (TiN) and amorphous (Si{sub 3}N{sub 4}) phases which confer a better protection against the corrosion effects compared with that of the AISI 316L.

  3. Proposal to negotiate a collaboration agreement related to the application of novel cavity fabrication techniques and Nb/Cu sputter coating technology in the field of superconducting RF for the Future Circular Collider (FCC) study

    CERN Document Server

    2015-01-01

    Proposal to negotiate a collaboration agreement related to the application of novel cavity fabrication techniques and Nb/Cu sputter coating technology in the field of superconducting RF for the Future Circular Collider (FCC) study

  4. 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)

    1994-12-31

    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.

  5. 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.

  6. An x-ray technique for precision laser beam synchronization

    International Nuclear Information System (INIS)

    Landen, O.L.; Lerche, R.A.; Hay, R.G.; Hammel, B.A.; Kalantar, D.; Cable, M.D.

    1994-01-01

    A new x-ray technique for recording the relative arrival times of multiple laser beams at a common target with better than ± 10 ps accuracy has been implemented at the Nova laser facility. 100 ps, 3ω Nova beam are focused to separate locations on a gold ribbon target viewed from the side. The measurement consists of using well characterized re-entrant x-ray streak cameras for 1-dimensional streaked imaging of the > 3 keV x-rays emanating from these isolated laser plasmas. After making the necessary correction for the differential laser, x-ray and electron transit times involved, timing offsets as low as ± 7 ps are resolved, and on subsequent shots, corrected for, verified and independently checked. This level of synchronization proved critical in meeting the power balance requirements for indirectly-driven pulse-shaped Nova implosions

  7. A new technique for ion beam tritium labelling

    International Nuclear Information System (INIS)

    Zhang Nianbao; Sheng Shugang; Yao Fuzeng

    1990-06-01

    An advanced technique, the ion beam tritium labelling method (IBTL), used for labelling proteins, peptides and other nonvolatile organic compounds is introduced. In this method the excited tritium ion beam is accelerated and then bombs a solid sample target in which tritium exchanging for hydrogen is taken place. The IBTL has been used for preparation of tritiated soybean trypsin inhibitor, ribonuclease A, elastin and pachyman etc. After purifing by dialysis, ion exchange chromatography and gel filtration, the tritiated proteins and polysaccharide were obtained with the specific activity over 37 GBq/mmol, the function of tritiated decomposition products was not found. The product was shown to have native biological activity. Amino acid analysis of tritiated protein showed that the relative specific radioactivities were higher for His., Tyr. and Phe. but lower for Val., Ile. and Ser

  8. 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...

  9. Effects of oxygen addition in reactive cluster beam deposition of tungsten by magnetron sputtering with gas aggregation

    International Nuclear Information System (INIS)

    Polášek, J.; Mašek, K.; Marek, A.; Vyskočil, J.

    2015-01-01

    In this work, we investigated the possibilities of tungsten and tungsten oxide nanoclusters generation by means of non-reactive and reactive magnetron sputtering with gas aggregation. It was found that in pure argon atmosphere, cluster aggregation proceeded in two regimes depending on argon pressure in the aggregation chamber. At the lower pressure, cluster generation was dominated by two-body collisions yielding larger clusters (about 5.5 nm in diameter) at lower rate. At higher pressures, cluster generation was dominated by three-body collisions yielding smaller clusters (3–4 nm in diameter) at higher rate. The small amount of oxygen admixture in the aggregation chamber had considerable influence on cluster aggregation process. At certain critical pressure, the presence of oxygen led to the raise of deposition rate and cluster size. Resulting clusters were composed mostly of tungsten trioxide. The oxygen pressure higher than critical led to the target poisoning and the decrease in the sputtering rate. Critical oxygen pressure decreased with increasing argon pressure, suggesting that cluster aggregation process was influenced by atomic oxygen species (namely, O"− ion) generated by oxygen–argon collisions in the magnetron plasma. - Highlights: • Formation of tungsten and tungsten oxide clusters was observed. • Two modes of cluster aggregation in pure argon atmosphere were found. • Dependence of cluster deposition speed and size on oxygen admixture was observed. • Changes of dependence on oxygen with changing argon pressure were described.

  10. Effects of oxygen addition in reactive cluster beam deposition of tungsten by magnetron sputtering with gas aggregation

    Energy Technology Data Exchange (ETDEWEB)

    Polášek, J., E-mail: xpolasekj@seznam.cz [Department of Surface and Plasma Science, Faculty of Mathematics and Physic, Charles University, V Holešovičkách 2, Prague 8, CZ-18000 (Czech Republic); Mašek, K. [Department of Surface and Plasma Science, Faculty of Mathematics and Physic, Charles University, V Holešovičkách 2, Prague 8, CZ-18000 (Czech Republic); Marek, A.; Vyskočil, J. [HVM Plasma Ltd., Na Hutmance 2, Prague 5, CZ-158 00 (Czech Republic)

    2015-09-30

    In this work, we investigated the possibilities of tungsten and tungsten oxide nanoclusters generation by means of non-reactive and reactive magnetron sputtering with gas aggregation. It was found that in pure argon atmosphere, cluster aggregation proceeded in two regimes depending on argon pressure in the aggregation chamber. At the lower pressure, cluster generation was dominated by two-body collisions yielding larger clusters (about 5.5 nm in diameter) at lower rate. At higher pressures, cluster generation was dominated by three-body collisions yielding smaller clusters (3–4 nm in diameter) at higher rate. The small amount of oxygen admixture in the aggregation chamber had considerable influence on cluster aggregation process. At certain critical pressure, the presence of oxygen led to the raise of deposition rate and cluster size. Resulting clusters were composed mostly of tungsten trioxide. The oxygen pressure higher than critical led to the target poisoning and the decrease in the sputtering rate. Critical oxygen pressure decreased with increasing argon pressure, suggesting that cluster aggregation process was influenced by atomic oxygen species (namely, O{sup −} ion) generated by oxygen–argon collisions in the magnetron plasma. - Highlights: • Formation of tungsten and tungsten oxide clusters was observed. • Two modes of cluster aggregation in pure argon atmosphere were found. • Dependence of cluster deposition speed and size on oxygen admixture was observed. • Changes of dependence on oxygen with changing argon pressure were described.

  11. Kinetic Monte Carlo simulations compared with continuum models and experimental properties of pattern formation during ion beam sputtering

    International Nuclear Information System (INIS)

    Chason, E; Chan, W L

    2009-01-01

    Kinetic Monte Carlo simulations model the evolution of surfaces during low energy ion bombardment using atomic level mechanisms of defect formation, recombination and surface diffusion. Because the individual kinetic processes are completely determined, the resulting morphological evolution can be directly compared with continuum models based on the same mechanisms. We present results of simulations based on a curvature-dependent sputtering mechanism and diffusion of mobile surface defects. The results are compared with a continuum linear instability model based on the same physical processes. The model predictions are found to be in good agreement with the simulations for predicting the early-stage morphological evolution and the dependence on processing parameters such as the flux and temperature. This confirms that the continuum model provides a reasonable approximation of the surface evolution from multiple interacting surface defects using this model of sputtering. However, comparison with experiments indicates that there are many features of the surface evolution that do not agree with the continuum model or simulations, suggesting that additional mechanisms are required to explain the observed behavior.

  12. Comparative microstructure and electrical property studies of lead scandium tantalate thin films as prepared by LDCVD, sol-gel and sputtering techniques

    International Nuclear Information System (INIS)

    Huang, Z; Donohue, P P; Zhang, Q; Williams, D J; Anthony, C J; Whatmore, R W; Todd, M A

    2003-01-01

    Lead scandium tantalate (PST) thin films for uncooled infrared (IR) detector applications have been deposited by liquid delivery chemical vapour deposition (LDCVD), sputtering and sol-gel techniques. The sol-gel and sputtered films were deposited at low temperature into a non-ferroelectric phase with the required perovskite structure being formed using a high temperature rapid thermal anneal (RTA). In contrast to this, the LDCVD films were deposited at high temperature directly into the perovskite phase but were found to still require a high temperature RTA step to optimize their merit for IR detection. Detailed structural and electrical characterization of the PST films deposited by these different methods have revealed that there is no simple relationship between microstructure and electrical properties. The sol-gel and LDCVD techniques produce thin films with excellent microstructures, as determined by x-ray diffraction analysis and transmission electron microscopy, but inferior electrical properties and relatively low merit figures. By contrast, the sputtered and then rapid thermal annealed films have inferior microstructures, characterized by extensive voiding, but excellent electrical properties and high merit figures

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

    NARCIS (Netherlands)

    Molenaar, P.A.; Straten, P. van der; Heideman, H.G.M.; Metcalf, H.

    1997-01-01

    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

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

    International Nuclear Information System (INIS)

    IghigeanuI, D.; Martin, D.; OproiuI, C.; Manaila, E.; Craciun, G.; Calinescu, I.; Zissulescu, E.

    2007-01-01

    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 SO 2 and NO x removal. Real synergy effects between EB induced NTP, MW induced NTP and catalysis can be observed

  15. Development of a micro-tomography technique by ion beams

    International Nuclear Information System (INIS)

    Moretto, Ph.; Michelet, C.

    1997-01-01

    The capability for an ion beam to penetrate easily the matter is an original feature for the nuclear microprobe analysis when compared to other techniques. Information in death of the sample can thus be obtained. Scanning Transmission Ion Microscopy (STIM) takes advantage of this capability to provide two dimensional maps of the sample thickness. Cross-sectional images of an object may be calculated from a set of STIM projections allowing the determination of the three-dimensional structure. This is the principle of STIM-Tomography. When PIXE analysis is carried out rotating the object under investigation, the elemental 3-D chemical distribution may also be elucidated at a microscopic scale. (authors)

  16. New approaches for investigating paintings by ion beam techniques

    International Nuclear Information System (INIS)

    Beck, L.; Viguerie, L. de; Walter, Ph.; Pichon, L.; Gutierrez, P.C.; Salomon, J.; Menu, M.; Sorieul, S.

    2010-01-01

    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).

  17. Beam synchronous detection techniques for X-Ray spectroscopy

    International Nuclear Information System (INIS)

    Goujon, Gérard; Rogalev, Andreï; Goulon, José; Feite, Serge; Wilhelm, Fabrice

    2013-01-01

    The Photo diode detectors combine a set of properties that make them most appropriate, in particular, for X-ray Magnetic Circular Dichroism (XMCD) experiments. Under standard operating conditions, the detection bandwidth is primarily limited by the transimpedance preamplifier that converts the very low ac photocurrent into a voltage. On the other hand, when the photodiode is reverse biased, its finite shunt resistance will cause an undesirable, temperature dependent DC dark current. The best strategy to get rid of it is to use synchronous detection techniques. A classical implementation is based on the use of a chopper modulating the X-ray beam intensity at rather low frequencies (typically below 1 kHz). Here we report on the recent development of a fast Xray detection which has the capability to fully exploit the frequency structure of the ESRF X-ray beam (355 KHz and its harmonics). The availability of new wide band preamplifiers allowed us to extend the working frequency range up to a few MHz. A beam synchronous data processing was implemented in large FPGAs. Performances of the new detection system implemented at the ESRF beamline ID12 are illustrated with detection of the Fe K-edge XMCD spectra in garnets, using 4 bunches operation mode with modulation frequency of 1.4 MHz.

  18. New approaches for investigating paintings by ion beam techniques

    Science.gov (United States)

    Beck, L.; de Viguerie, L.; Walter, Ph.; Pichon, L.; Gutiérrez, P. C.; Salomon, J.; Menu, M.; Sorieul, S.

    2010-06-01

    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).

  19. New approaches for investigating paintings by ion beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Beck, L., E-mail: Lucile.beck@cea.f [Centre de Recherche et de Restauration des Musees de France (C2RMF), CNRS-UMR 171, Palais du Louvre - Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); Viguerie, L. de; Walter, Ph.; Pichon, L. [Centre de Recherche et de Restauration des Musees de France (C2RMF), CNRS-UMR 171, Palais du Louvre - Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); Gutierrez, P.C. [Centro de Micro-Analisis de Materiales (CMAM), Universidad Autonoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Salomon, J.; Menu, M. [Centre de Recherche et de Restauration des Musees de France (C2RMF), CNRS-UMR 171, Palais du Louvre - Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); Sorieul, S. [Centre d' Etudes Nucleaires de Bordeaux-Gradignan, IN2P3, UMR 5797, Universite de Bordeaux 1, Chemin du Solarium BP120, 33175 Gradignan Cedex (France)

    2010-06-15

    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).

  20. Neutral atom beam technique enhances bioactivity of PEEK

    International Nuclear Information System (INIS)

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

    2013-01-01

    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

  1. Proton sputtering. Final report

    International Nuclear Information System (INIS)

    Finfgeld, C.R.

    1975-01-01

    This research provides sputtering yields as a function of energy for H + and D + on several representative pure metallic elements, in the absence of surface contaminants. The experimental technique and apparatus are described. Data are given for Au, Co, Ta, W, and Mo

  2. Modification of PMMA/graphite nanocomposites through ion beam technique

    Science.gov (United States)

    Singhal, Prachi; Rattan, Sunita; Avasthi, Devesh Kumar; Tripathi, Ambuj

    2013-08-01

    Swift heavy ion (SHI) irradiation is a special technique for inducing physical and chemical modifications in bulk materials. In the present work, the SHI hs been used to prepare nanocomposites with homogeneously dispersed nanoparticles. The nanographite was synthesized from graphite using the intercalation-exfoliation method. PMMA Poly(methyl methacrylate)/graphite nanocomposites have been synthesized by in situ polymerization. The prepared PMMA/graphite nanocomposite films were irradiated with SHI irradiation (Ni ion beam, 80 MeV and C ion beam, 50 MeV) at a fluence of 1×1010 to 3×1012 ions/cm2. The nanocomposite films were characterized by scanning electron microscope (SEM) and were evaluated for their electrical and sensor properties. After irradiation, significant changes in surface morphology of nanocomposites were observed as evident from the SEM images, which show the presence of well-distributed nanographite platelets. The irradiated nanocomposites exhibit better electrical and sensor properties for the detection of nitroaromatics with marked improvement in sensitivity as compared with unirradiated nanocomposites.

  3. Electrostatic mechanism of shaping the wave micro-relief on the surface of a semiconductor, sputtered by an ion beam

    International Nuclear Information System (INIS)

    Grigor'ev, A.I.

    2000-01-01

    The effect of the electric field formed due to the surface charging, is not accounted for in the weakly-developed theoretical models for the ordered micro-relief formation on the surface of a semiconductor under the impact of an ion beam. It is shown, that the problem on modeling the physical mechanism of forming the ordered wave micro-relief on the semiconductor surface under the impact of a high-energy ion beam may be interpreted as an electrostatic one [ru

  4. Effects of ion sputtering on semiconductor surfaces

    International Nuclear Information System (INIS)

    McGuire, G.E.

    1978-01-01

    Ion beam sputtering has been combined with Auger spectroscopy to study the effects of ion beams on semiconductor surfaces. Observations on the mass dependence of ion selective sputtering of two component systems are presented. The effects of ion implantation are explained in terms of atomic dilution. Experimental data are presented that illustrate the super-position of selective sputtering and implantation effects on the surface composition. Sample reduction from electron and ion beam interaction is illustrated. Apparent sample changes which one might observe from the effects of residual gas contamination and electric fields are also discussed. (Auth.)

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

    OpenAIRE

    Molenaar, P.A.; Straten, P. van der; Heideman, H.G.M.; Metcalf, H.

    1997-01-01

    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...

  6. A new technique of ion beam tritium labelling

    International Nuclear Information System (INIS)

    Zhang Nianbao; Sheng Shugang; Yao Fuzeng

    1990-01-01

    In this paper a new technique is reported for tritium labelling of proteins, peptides and other nonvolatile organic compounds. A tritium ion beam is accelerated to bombard solid sample target for producing tritium exchange with hydrogen. The tritium labelling method has been applied to tritiated soybean trypsin inhibitor, ribonuclease A, elastin, pachyman and others totalled 11. After purifying by dialysis, ion exchange chromatography and gel filtration, the tritiated proteins and polysaccharide were obtained with specific activity over 37 GBq/mmol, without decomposition and with biological activity well preserved. By amino acid analysis of tritiated protein it was shown that the relative specific radioactivities for His., Tyr. and Phe. residues were higher while those for Val., Ile. and Ser. residues were lower

  7. Multi-beam backscatter image data processing techniques employed to EM 1002 system

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, W.A.; Chakraborty, B.

    to compensate outer-beam backscatter strength data in such a way that the effect of angular backscatter strength is removed. In this work we have developed backscatter data processing techniques for EM1002 multi-beam system...

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

    International Nuclear Information System (INIS)

    Beck, L.

    2013-01-01

    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) [fr

  9. Thermally induced formation of SiC nanoparticles from Si/C/Si multilayers deposited by ultra-high-vacuum ion beam sputtering

    International Nuclear Information System (INIS)

    Chung, C-K; Wu, B-H

    2006-01-01

    A novel approach for the formation of SiC nanoparticles (np-SiC) is reported. Deposition of Si/C/Si multilayers on Si(100) wafers by ultra-high-vacuum ion beam sputtering was followed by thermal annealing in vacuum for conversion into SiC nanoparticles. The annealing temperature significantly affected the size, density, and distribution of np-SiC. No nanoparticles were formed for multilayers annealed at 500 0 C, while a few particles started to appear when the annealing temperature was increased to 700 0 C. At an annealing temperature of 900 0 C, many small SiC nanoparticles, of several tens of nanometres, surrounding larger submicron ones appeared with a particle density approximately 16 times higher than that observed at 700 0 C. The higher the annealing temperature was, the larger the nanoparticle size, and the higher the density. The higher superheating at 900 0 C increased the amount of stable nuclei, and resulted in a higher particle density compared to that at 700 0 C. These particles grew larger at 900 0 C to reduce the total surface energy of smaller particles due to the higher atomic mobility and growth rate. The increased free energy of stacking defects during particle growth will limit the size of large particles, leaving many smaller particles surrounding the large ones. A mechanism for the np-SiC formation is proposed in this paper

  10. Ion beam analysis, corrosion resistance and nanomechanical properties of TiAlCN/CN{sub x} multilayer grown by reactive magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Alemón, B.; Flores, M. [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, J. Guadalupe Zuno 48, Los Belenes, Zapopan, Jal. 45101 (Mexico); Canto, C. [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, Mexico, DF 04510 (Mexico); Andrade, E., E-mail: andrade@fisica.unam.mx [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, Mexico, DF 04510 (Mexico); Lucio, O.G. de [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, Mexico, DF 04510 (Mexico); Rocha, M.F. [ESIME-Z, Instituto Politécnico Nacional, ALM Zacatenco, Mexico, DF 07738 (Mexico); Broitman, E. [Thin Films Physics Division, IFM, Linköping University, SE-58183 Linköping (Sweden)

    2014-07-15

    A novel TiAlCN/CN{sub x} multilayer coating, consisting of nine TiAlCN/CN{sub x} periods with a top layer 0.5 μm of CN{sub x}, was designed to enhance the corrosion resistance of CoCrMo biomedical alloy. The multilayers were deposited by dc and RF reactive magnetron sputtering from Ti{sub 0.5}Al{sub 0.5} and C targets respectively in a N{sub 2}/Ar plasma. The corrosion resistance and mechanical properties of the multilayer coatings were analyzed and compared to CoCrMo bulk alloy. Ion beam analysis (IBA) and X-ray diffraction tests were used to measure the element composition profiles and crystalline structure of the films. Corrosion resistance was evaluated by means of potentiodynamic polarization measurements using simulated body fluid (SBF) at typical body temperature and the nanomechanical properties of the multilayer evaluated by nanoindentation tests were analyzed and compared to CoCrMo bulk alloy. It was found that the multilayer hardness and the elastic recovery are higher than the substrate of CoCrMo. Furthermore the coated substrate shows a better general corrosion resistance than that of the CoCrMo alloy alone with no observation of pitting corrosion.

  11. Low temperature growth of Co{sub 2}MnSi films on diamond semiconductors by ion-beam assisted sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Nishiwaki, M.; Ueda, K., E-mail: k-ueda@numse.nagoya-u.ac.jp; Asano, H. [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2015-05-07

    High quality Schottky junctions using Co{sub 2}MnSi/diamond heterostructures were fabricated. Low temperature growth at ∼300–400 °C by using ion-beam assisted sputtering (IBAS) was necessary to obtain abrupt Co{sub 2}MnSi/diamond interfaces. Only the Co{sub 2}MnSi films formed at ∼300–400 °C showed both saturation magnetization comparable to the bulk values and large negative anisotropic magnetoresistance, which suggests half-metallic nature of the Co{sub 2}MnSi films, of ∼0.3% at 10 K. Schottky junctions formed using the Co{sub 2}MnSi films showed clear rectification properties with rectification ratio of more than 10{sup 7} with Schottky barrier heights of ∼0.8 eV and ideality factors (n) of ∼1.2. These results indicate that Co{sub 2}MnSi films formed at ∼300–400 °C by IBAS are a promising spin source for spin injection into diamond semiconductors.

  12. Ion beam sputter deposited TiAlN films for metal-insulator-metal (Ba,Sr)TiO{sub 3} capacitor application

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.-Y. [Department of Materials Science and Engineering, National Cheng Kung University, No. 1, Ta-Hsueh Road, Tainan, Taiwan (China); Wang, S.-C. [Department of Mechanical Engineering, Southern Taiwan University of Technology, No. 1, Nantai St, Yung-Kang City, Tainan, Taiwan (China); Chen, J.-S. [Department of Materials Science and Engineering, National Cheng Kung University, No. 1, Ta-Hsueh Road, Tainan, Taiwan (China); Huang, J.-L. [Department of Materials Science and Engineering, National Cheng Kung University, No. 1, Ta-Hsueh Road, Tainan, Taiwan (China)], E-mail: jlh888@mail.ncku.edu.tw

    2008-09-01

    The present study evaluated the feasibility of TiAlN films deposited using the ion beam sputter deposition (IBSD) method for metal-insulator-metal (MIM) (Ba,Sr)TiO{sub 3} (BST) capacitors. The BST films were crystallized at temperatures above 650 deg. C. TiAlN films deposited using the IBSD method were found having smooth surface and low electrical resistivity at high temperature conditions. TiAlN films showed a good diffusion barrier property against BST components. The J-E (current density-electric field) characteristics of Al/BST/TiAlN capacitors were good, with a high break down electric field of {+-} 2.5 MV/cm and a leakage current density of about 1 x 10{sup -5} A/cm{sup 2} at an applied field of {+-} 0.5 MV/cm. Thermal stress and lateral oxidation that occurred at the interface damaged the capacitor stacking structure. Macro holes that dispersed on the films resulted in higher leakage current and inconsistent J-E characteristics. Vacuum annealing with lower heating rate and furnace cooling, and a Ti-Al adhesion layer between TiAlN and the SiO{sub 2}/Si substrate can effectively minimize the stress effect. TiAlN film deposited using IBSD can be considered as a potential electrode and diffusion barrier material for MIM BST capacitors.

  13. ITO films realized at room-temperature by ion beam sputtering for high-performance flexible organic light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, B.; Rammal, W.; Moliton, A. [Limoges Univ., Faculte des Sciences et Techniques, CNRS, UMR 6172, Institut de Recherche XLIM, Dept. MINACOM, 87 - Limoges (France)

    2006-06-15

    Indium-tin oxide (ITO) thin layers are obtained by an IBS (Ion Beam Sputtering) deposition process. We elaborated ITO films on flexible substrates of polyethylene terephthalate (PET), under soft conditions of low temperatures and fulfilling the requirements of fabrication processes of the organic optoelectronic components. With a non thermally activated (20 Celsius degrees) ITO deposition assisted by an oxygen flow (1 cm{sup 3}/min), we got an optical transmittance of 90% in the visible range, a resistivity around 10{sup -3} {omega}.cm and a surface roughness lower than 1.5 mm. Thus we realized flexible organic light-emitting diodes (FOLEDs) with good performances: a maximum luminance of 12000 cd/m{sup 2} at a voltage of 19 V and a maximum luminous power efficiency around 1 lm/W at a voltage of 10 V (or a maximum current efficiency of 4 cd/A at 14 V) for the (PET(50 {mu}m) / ITO(200 nm) / TPD(40 nm) / Alq3(60 nm) / Ca / Al) structure. (authors)

  14. Two-dimensional electron gases in MgZnO/ZnO and ZnO/MgZnO/ZnO heterostructures grown by dual ion beam sputtering

    Science.gov (United States)

    Singh, Rohit; Arif Khan, Md; Sharma, Pankaj; Than Htay, Myo; Kranti, Abhinav; Mukherjee, Shaibal

    2018-04-01

    This work reports on the formation of high-density (~1013-1014 cm-2) two-dimensional electron gas (2DEG) in ZnO-based heterostructures, grown by a dual ion beam sputtering system. We probe 2DEG in bilayer MgZnO/ZnO and capped ZnO/MgZnO/ZnO heterostructures utilizing MgZnO barrier layers with varying thickness and Mg content. The effect of the ZnO cap layer thickness on the ZnO/MgZnO/ZnO heterostructure is also studied. Hall measurements demonstrate that the addition of a 5 nm ZnO cap layer results in an enhancement of the 2DEG density by about 1.5 times compared to 1.11 × 1014 cm-2 for the uncapped bilayer heterostructure with the same 30 nm barrier thickness and 30 at.% Mg composition in the barrier layer. From the low-temperature Hall measurement, the sheet carrier concentration and mobility are both found to be independent of the temperature. The capacitance-voltage measurement suggests a carrier density of ~1020 cm-3, confined in 2DEG at the MgZnO/ZnO heterointerface. The results presented are significant for the optimization of 2DEG for the eventual realization of cost-effective and large-area MgZnO/ZnO-based high-electron-mobility transistors.

  15. The effect of substrate bias voltages on impact resistance of CrAlN coatings deposited by modified ion beam enhanced magnetron sputtering

    Science.gov (United States)

    Chunyan, Yu; Linhai, Tian; Yinghui, Wei; Shebin, Wang; Tianbao, Li; Bingshe, Xu

    2009-01-01

    CrAlN coatings were deposited on silicon and AISI H13 steel substrates using a modified ion beam enhanced magnetron sputtering system. The effect of substrate negative bias voltages on the impact property of the CrAlN coatings was studied. The X-ray diffraction (XRD) data show that all CrAlN coatings were crystallized in the cubic NaCl B1 structure, with the (1 1 1), (2 0 0) (2 2 0) and (2 2 2) diffraction peaks observed. Two-dimensional surface morphologies of CrAlN coatings were investigated by atomic force microscope (AFM). The results show that with increasing substrate bias voltage the coatings became more compact and denser, and the microhardness and fracture toughness of the coatings increased correspondingly. In the dynamic impact resistance tests, the CrAlN coatings displayed better impact resistance with the increase of bias voltage, due to the reduced emergence and propagation of the cracks in coatings with a very dense structure and the increase of hardness and fracture toughness in coatings.

  16. Ion beam sputter deposited TiAlN films for metal-insulator-metal (Ba,Sr)TiO3 capacitor application

    International Nuclear Information System (INIS)

    Lee, S.-Y.; Wang, S.-C.; Chen, J.-S.; Huang, J.-L.

    2008-01-01

    The present study evaluated the feasibility of TiAlN films deposited using the ion beam sputter deposition (IBSD) method for metal-insulator-metal (MIM) (Ba,Sr)TiO 3 (BST) capacitors. The BST films were crystallized at temperatures above 650 deg. C. TiAlN films deposited using the IBSD method were found having smooth surface and low electrical resistivity at high temperature conditions. TiAlN films showed a good diffusion barrier property against BST components. The J-E (current density-electric field) characteristics of Al/BST/TiAlN capacitors were good, with a high break down electric field of ± 2.5 MV/cm and a leakage current density of about 1 x 10 -5 A/cm 2 at an applied field of ± 0.5 MV/cm. Thermal stress and lateral oxidation that occurred at the interface damaged the capacitor stacking structure. Macro holes that dispersed on the films resulted in higher leakage current and inconsistent J-E characteristics. Vacuum annealing with lower heating rate and furnace cooling, and a Ti-Al adhesion layer between TiAlN and the SiO 2 /Si substrate can effectively minimize the stress effect. TiAlN film deposited using IBSD can be considered as a potential electrode and diffusion barrier material for MIM BST capacitors

  17. The preparation of Zn-ferrite epitaxial thin film from epitaxial Fe3O4:ZnO multilayers by ion beam sputtering deposition

    International Nuclear Information System (INIS)

    Su, Hui-Chia; Dai, Jeng-Yi; Liao, Yen-Fa; Wu, Yu-Han; Huang, J.C.A.; Lee, Chih-Hao

    2010-01-01

    A new method to grow a well-ordered epitaxial ZnFe 2 O 4 thin film on Al 2 O 3 (0001) substrate is described in this work. The samples were made by annealing the ZnO/Fe 3 O 4 multilayer which was grown with low energy ion beam sputtering deposition. Both the Fe 3 O 4 and ZnO layers were found grown epitaxially at low temperature and an epitaxial ZnFe 2 O 4 thin film was formed after annealing at 1000 o C. X-ray diffraction shows the ZnFe 2 O 4 film is grown with an orientation of ZnFe 2 O 4 (111)//Al 2 O 3 (0001) and ZnFe 2 O 4 (1-10)//Al 2 O 3 (11-20). X-ray absorption spectroscopy studies show that Zn 2+ atoms replace the tetrahedral Fe 2+ atoms in Fe 3 O 4 during the annealing. The magnetic properties measured by vibrating sample magnetometer show that the saturation magnetization of ZnFe 2 O 4 grown from ZnO/Fe 3 O 4 multilayer reaches the bulk value after the annealing process.

  18. Domain structure and magnetic properties of epitaxial SrRuO sub 3 films grown on SrTiO sub 3 (100) substrates by ion beam sputtering

    CERN Document Server

    Oh, S H

    2000-01-01

    The domain structure of epitaxial SrRuO sub 3 thin films grown on SrTiO sub 3 (100) substrates by using ion beam sputtering has been investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). The SrRuO sub 3 films grown in the present study revealed a unique cube-on-cube epitaxial relationship, i.e., (100) sub S sub R sub O ll (100) sub S sub T sub O , [010] sub S sub R sub O ll [101] sub S sub T sub O , prevailing with a cubic single-domain structure. The cubic SrRuO sub 3 thin films that were inherently with free from RuO sub 6 octahedron tilting exhibited higher resistivity with suppressed magnetic properties. The Curie temperature of the thin films was suppressed by 60 K from 160 K for the bulk specimen, and the saturation magnetic moment was reduced by a significant amount. The tetragonal distortion of the SrRuO sub 3 thin films due to coherent growth with the substrate seemed to result in a strong magnetic anisotropy.

  19. Electronic sputtering

    International Nuclear Information System (INIS)

    Johnson, R.E.

    1989-01-01

    Electronic sputtering covers a range of phenomena from electron and photon stimulated desorption from multilayers to fast heavy ion-induced desorption (sputtering) of biomolecules. In this talk the author attempted. Therefore, to connect the detailed studies of argon ejection from solid argon by MeV ions and keV electrons to the sputtering of low temperatures molecular ices by MeV ions then to biomolecule ejection from organic solids. These are related via changing (dE/dx) e , molecular size, and transport processes occurring in materials. In this regard three distinct regions of (dE/dx) e have been identified. Since the talk this picture has been made explicit using a simple spike model for individual impulsive events in which spike interactions are combined linearly. Since that time also the molecular dynamics programs (at Virginia and Uppsala) have quantified both single atom and dimer processes in solid Ar and the momentum transport in large biomolecule sputtering. 5 refs

  20. Simulation experiments and solar wind sputtering

    International Nuclear Information System (INIS)

    Griffith, J.E.; Papanastassiou, D.A.; Russell, W.A.; Tombrello, T.A.; Weller, R.A.

    1978-01-01

    In order to isolate the role played by solar wind sputtering from other lunar surface phenomena a number of simulation experiments were performed, including isotope abundance measurements of Ca sputtered from terrestrial fluorite and plagioclase by 50-keV and 130-keV 14 N beams, measurement of the energy distribution of U atoms sputtered with 80-keV 40 Ar, and measurement of the fraction of sputtered U atoms which stick on the surfaces used to collect these atoms. 10 references

  1. Techniques for slow positron beam generation and the applications

    International Nuclear Information System (INIS)

    Okada, Sohei

    1994-01-01

    Slow positron beams have been expected to be a powerful tool for observation of nature in wide range of research fields from materials science to basic physics, chemistry and biology. In this paper, at first, the beam technology is reviewed, which includes the positron generation, the transformation to slow positron beams and the beam manipulation such as beam stretching, bunching and brightness enhancement. Next, the present status of the slow positron beam applications to a variety of fields is demonstrated in terms of special characteristics of positron, that is, depth controllability, surface sensitivity, unique ionization channels and elemental anti-particle properties. Finally, prospects to produce intense slow positron beams are described. (author) 65 refs

  2. Alkali metal adsorbate sputtering by molecular impact

    International Nuclear Information System (INIS)

    Moran, J.P.; Wachman, H.Y.; Trilling, L.

    1974-01-01

    An exploratory study of the sputtering by a krypton molecular beam of rubidium adsorbed at low coverage on a tungsten substrate has been described in a previous paper. An extension of this work is reported now

  3. Application of a transverse phase-space measurement technique for high-brightness, H- beams to the GTA H- beam

    International Nuclear Information System (INIS)

    Johnson, K.F.; Garcia, R.C.; Rusthoi, D.P.; Sander, O.R.; Sandoval, D.P.; Shinas, M.A.; Smith, M.; Yuan, V.W.; Connolly, R.C.

    1995-01-01

    The Ground Test Accelerator (GTA) had the objective Of Producing a high-brightness, high-current H-beam. The major components were a 35 keV injector, a Radio Frequency Quadrupole (RFQ), an intertank matching section (IMS), and a drift tube linac (DTL), consisting of 10 modules. A technique for measuring the transverse phase-space of high-power density beams has been developed and tested. This diagnostic has been applied to the GTA H-beam. Experimental results are compared to the slit and collector technique for transverse phase-space measurements and to simulations

  4. Synthesis and characterization of Al2O3 and SiO2 films with fluoropolymer content using rf-plasma magnetron sputtering technique

    International Nuclear Information System (INIS)

    Islam, Mohammad; Inal, Osman T.

    2008-01-01

    Pure and molecularly mixed inorganic films for protection against atomic oxygen in lower earth orbit were prepared using radio-frequency (rf) plasma magnetron sputtering technique. Alumina (Al 2 O 3 ) and silica (SiO 2 ) films with average grain size in the range of 30-80 nm and fully dense or dense columnar structure were synthesized under different conditions of pressure and power. Simultaneous oxide sputtering and plasma polymerization (PP) of hexafluoropropylene (HFP) led to the formation of molecularly mixed films with fluoropolymer content. The degree of plasma polymerization was strongly influenced by total chamber pressure and the argon to HFP molar ratio (n Ar /n M ). An order of magnitude increase in pressure due to argon during codeposition changed the plasma-polymerization mechanism from radical-chain- to radical-radical-type processes. Subsequently, a shift from linear CH 2 group based chain polymerization to highly disordered fluoropolymer content with branching and cross-linking was observed. Fourier transform infrared spectroscopy studies revealed chemical interaction between depositing SiO 2 and PP-HFP through appearance of absorption bands characteristic of Si-F stretching and expansion of SiO 2 network. The relative amount and composition of plasma-polymerized fluoropolymer in such films can be controlled by changing argon to HFP flow ratio, total chamber pressure, and applied power. These films offer great potential for use as protective coatings in aerospace applications

  5. Optical and structural characterization of titanium dioxide films growth by the r f-sputtering technique; Caracterizacion optica y estructural de peliculas de dioxido de titanio crecidas por la tecnica de rf-sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Florido C, A.; Calderon, A. [CICATA-IPN, Av. Legaria 694, 11500 Mexico D.F. (Mexico); Mendoza A, J.G.; Becerril, M.; Zelaya A, O. [CINVESTAV, A.P. 14-740, 07000 Mexico D.F. (Mexico)

    2007-07-01

    Full text: The elaboration of a series of grown films of TiO on Corning glaze substrates, as well as silicon, by means of the rf-sputtering technique using one power of 160 watts, with the objective of obtaining the anatase phase which one presents better activity for applications in photo catalysis. In the process of growth it was used a temperature in the range from 300 to 600 C and a separation distance among the target and the substrate of 3.5 cm. The used atmosphere was a mixture of argon and oxygen. It was carried out the characterization of the films obtained by means of UV-vis spectrophotometry, and photoluminescence (FL). The microstructure analysis was carried out by means of X-ray diffraction (XRD), micro-Raman (MR), and atomic force microscopy (AFM). By means of the diffractographs it was determined the grain size. Our results show that in our films they are present the anatase and rutile phases of the titanium dioxide. The analysis of the results of optical spectra shows a forbidden band of the titanium dioxide around 3.2 eV. (Author)

  6. POLYMER COMPOSITE FILMS WITH SIZE-SELECTED METAL NANOPARTICLES FABRICATED BY CLUSTER BEAM TECHNIQUE

    DEFF Research Database (Denmark)

    Ceynowa, F. A.; Chirumamilla, Manohar; Popok, Vladimir

    2017-01-01

    Formation of polymer films with size-selected silver and copper nanoparticles (NPs) is studied. Polymers are prepared by spin coating while NPs are fabricated and deposited utilizing a magnetron sputtering cluster apparatus. The particle embedding into the films is provided by thermal annealing...... after the deposition. The degree of immersion can be controlled by the annealing temperature and time. Together with control of cluster coverage the described approach represents an efficient method for the synthesis of thin polymer composite layers with either partially or fully embedded metal NPs....... Combining electron beam lithography, cluster beam deposition and thermal annealing allows to form ordered arrays of metal NPs on polymer films. Plasticity and flexibility of polymer host and specific properties added by coinage metal NPs open a way for different applications of such composite materials...

  7. The effect of CFRP on retrofitting of damaged HSRC beams using AE technique

    Science.gov (United States)

    Soffian Noor, M. S.; Noorsuhada, M. N.

    2017-12-01

    This paper presents the effect of carbon fibre reinforced polymer (CFRP) on retrofitted high strength reinforced concrete (HSRC) beams using acoustic emission (AE) technique. Two RC beam parameters were prepared. The first was the control beam which was undamaged HSRC beam. The second was the damaged HSRC beam retrofitted with CFRP on the soffit. The main objective of this study is to assess the crack modes of HSRC beams using AE signal strength. The relationship between signal strength, load and time were analysed and discussed. The crack pattern observed from the visual observation was also investigated. HSRC beam retrofitted with CFRP produced high signal strength compared to control beam. It demonstrates the effect of the AE signal strength for interpretation and prediction of failure modes that might occur in the beam specimens.

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

    International Nuclear Information System (INIS)

    Shoji, Y.; Sato, H.; Toyama, T.; Marutsuka, K.; Sueno, T.; Mikawa, K.; Ninomiya, S.; Yoshii, M.

    1992-01-01

    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)

  9. Novel non-intercepting diagnostic techniques for low-emittance relativistic electron beams

    International Nuclear Information System (INIS)

    Moran, M.J.; Chang, B.

    1988-01-01

    Relativistic electron beams are being generated with emittances low enough that diffraction radiation can be used for beam diagnostics. Techniques based on diffraction radiation can be used to measure the beam transverse momentum distribution and to measure the transverse spatial distribution. The radiation is intense and can be in the visible spectral region where optical diagnostic techniques can be used to maximum advantage. 4 refs. 3 figs

  10. Development of a computerized tomographic system based on the FAN-BEAM technique

    International Nuclear Information System (INIS)

    Junqueira, M.M.; Santos, C.A.C.; Borges, J.C.

    1986-01-01

    The Nuclear Instrumentation Laboratory, at COPPE/UFRJ, concentrates its researches in the development of computerized tomographic systems, looking for applications in industrial and medical non destructive analysing techniques. In this work we have projected and constructed a tomographic prototype, based on the FAN-BEAM technique for irradiating the object under analysis. An algorithm previously developed to analyse parallel beams, was modified and adapted to the FAN-BEAM geometry. (Author) [pt

  11. The status and new trends of ion beam induced charge technique

    International Nuclear Information System (INIS)

    Lu Rongrong; Qiu Huiyuan; Zhu Dezhang

    2002-01-01

    Ion beam induced charge technique (IBIC) with low beam current (fA level) and high efficiency is a new development of nuclear microscopy. It has been widely applied to the fields of semiconductor and microelectronic materials. The principle and the experimental method of the IBIC technique were described and reviewed its status and new trends were reviewed

  12. An isodose shift technique for obliquely incident electron beams

    International Nuclear Information System (INIS)

    Ulin, K.; Sternick, E.S.

    1989-01-01

    It is well known that when an electron beam is incident obliquely on the surface of a phantom, the depth dose curve measured normal to the surface is shifted toward the surface. Based on geometrical arguments alone, the depth of the nth isodose line for an electron beam incident at an angle θ should be equal to the product of cos θ and the depth of the nth isodose line at normal incidence. This method, however, ignores the effects of scatter and can lead to significant errors in isodose placement for beams at large angles of incidence. A semi-empirical functional relationship and a table of isodose shift factors have been developed with which one may easily calculate the depth of any isodose line for beams at incident angles of 0 degree to 60 degree. The isodose shift factors are tabulated in terms of beam energy (6--22 MeV) and isodose line (10%--90%) and are shown to be relatively independent of beam size and incident angle for angles <60 degree. Extensive measurements have been made on a Varian Clinac 2500 linear accelerator with a parallel-plate chamber and polystyrene phantom. The dependence of the chamber response on beam angulation has been checked, and the scaling factor of the polystyrene phantom has been determined to be equal to 1.00

  13. Carbon thin films deposited by the magnetron sputtering technique using cobalt, copper and nickel as buffer-layers; Filmes finos de carbono depositados por meio da tecnica de magnetron sputtering usando cobalto, cobre e niquel como buffer-layers

    Energy Technology Data Exchange (ETDEWEB)

    Costa e Silva, Danilo Lopes

    2015-11-01

    In this work, carbon thin films were produced by the magnetron sputtering technique using single crystal substrates of alumina c-plane (0001) and Si (111) and Si (100) substrates, employing Co, Ni and Cu as intermediate films (buffer-layers). The depositions were conducted in three stages, first with cobalt buffer-layers where only after the production of a large number of samples, the depositions using cooper buffer-layers were carried out on Si substrates. Then, depositions were performed with nickel buffer layers using single-crystal alumina substrates. The crystallinity of the carbon films was evaluated by using the technique of Raman spectroscopy and, then, by X-ray diffraction (XRD). The morphological characterization of the films was performed by scanning electron microscopy (SEM and FEG-SEM) and high-resolution transmission electron microscopy (HRTEM). The XRD peaks related to the carbon films were observed only in the results of the samples with cobalt and nickel buffer-layers. The Raman spectroscopy showed that the carbon films with the best degree of crystallinity were the ones produced with Si (111) substrates, for the Cu buffers, and sapphire substrates for the Ni and Co buffers, where the latter resulted in a sample with the best crystallinity of all the ones produced in this work. It was observed that the cobalt has low recovering over the alumina substrates when compared to the nickel. Sorption tests of Ce ions by the carbon films were conducted in two samples and it was observed that the sorption did not occur probably because of the low crystallinity of the carbon films in both samples. (author)

  14. Resonance ionization mass spectrometry of ion beam sputtered neutrals for element- and isotope-selective analysis of plutonium in micro-particles

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, N. [Institute for Transuranium Elements, European Commission Joint Research Centre, Karlsruhe (Germany); Kratz, J.V.; Trautmann, N. [Johannes Gutenberg-University Mainz, Institute of Nuclear Chemistry, Mainz (Germany); Passler, G. [Johannes Gutenberg-University Mainz, Institute of Physics, Mainz (Germany)

    2009-11-15

    Micro-particles containing actinides are of interest for risk assessments of contaminated areas, nuclear forensic analyses, and IAEA as well as Euratom safeguards programs. For their analysis, secondary ion mass spectrometry (SIMS) has been established as the state-of-the-art standard technique. In the case of actinide mixtures within the particles, however, SIMS suffers from isobaric interferences (e.g., {sup 238}U/{sup 238}Pu, {sup 241}Am/{sup 241}Pu). This can be eliminated by applying resonance ionization mass spectrometry which is based on stepwise resonant excitation and ionization of atoms with laser light, followed by mass spectrometric detection of the produced ions, combining high elemental selectivity with the analysis of isotopic compositions. This paper describes the instrumental modifications for coupling a commercial time-of-flight (TOF)-SIMS apparatus with three-step resonant post-ionization of the sputtered neutrals using a high-repetition-rate (kHz) Nd:YAG laser pumped tunable titanium:sapphire laser system. Spatially resolved ion images obtained from actinide-containing particles in TOF-SIMS mode demonstrate the capability for isotopic and spatial resolution. Results from three-step resonant post-ionization of bulk Gd and Pu samples successfully demonstrate the high elemental selectivity of this process. (orig.)

  15. 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

  16. 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

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

    DEFF Research Database (Denmark)

    Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup

    2012-01-01

    BEAMING is a telepresence research project aiming at providing a multimodal interaction between two or more participants located at distant locations. One of the BEAMING applications allows a distant teacher to give a xylophone playing lecture to the students. Therefore, rendering of the xylophon...... to spatial improvements mainly in terms of the Apparent Source Width (ASW). Rendered examples are subjectively evaluated in listening tests by comparing them with binaural recording....

  18. Reduction of residual gas in a sputtering system by auxiliary sputter of rare-earth metal

    International Nuclear Information System (INIS)

    Li Dejie

    2002-01-01

    In film deposition by sputtering, the oxidation and nitrification of the sputtered material lead to degradation of film quality, particularly with respect to metal sulfide films. We propose to use auxiliary sputtering as a method to produce a fresh film of rare-earth metal, usually dysprosium (Dy), that absorbs the active gases in a sputtering system, greatly reducing the background pressure and protecting the film from oxidation and nitrification effectively. The influence of the auxiliary sputtering power consumption, sputtering time, and medium gas pressure on the background pressure in the vacuum chamber is investigated in detail. If the auxiliary sputtering power exceeds 120 W and the sputtering time is more than 4 min, the background pressure is only one fourth of the ultimate pressure pumped by an oil diffusion pump. The absorption activity of the sputtered Dy film continues at least an hour after completion of the auxiliary sputter. Applied to film deposition of Ti and ZnS, this technique has been proven to be effective. For the Ti film, the total content of N and O is reduced from 45% to 20% when the auxiliary sputtering power of Dy is 120 W, and the sputtering time is 20 min. In the case of ZnS, the content of O is reduced from 8% to 2%

  19. Study of magnetic properties and relaxation in amorphous Fe73.9Nb3.1Cu0.9Si13.2B8.9 thin films produced by ion beam sputtering

    International Nuclear Information System (INIS)

    Celegato, F.; Coiesson, M.; Magni, A.; Tiberto, P.; Vinai, F.; Kane, S. N.; Modak, S. S.; Gupta, A.; Sharma, P.

    2007-01-01

    Amorphous Fe 73.9 Nb 3.1 Cu 0.9 Si 13.2 B 8.9 thin films have been produced by ion beam sputtering with two different beam energies (500 and 1000 eV). Magnetic measurements indicate that the samples display a uniaxial magnetic anisotropy, especially for samples prepared with the lower beam energy. Magnetization relaxation has been measured on both films with an alternating gradient force magnetometer and magneto-optical Kerr effect. Magnetization relaxation occurs on time scales of tens of seconds and can be described with a single stretched exponential function. Relaxation intensity turns out to be higher when measured along the easy magnetization axis

  20. Beam-based alignment technique for the SLC [Stanford Linear Collider] linac

    International Nuclear Information System (INIS)

    Adolphsen, C.E.; Lavine, T.L.; Atwood, W.B.

    1989-03-01

    Misalignment of quadrupole magnets and beam position monitors (BPMs) in the linac of the SLAC Linear Collider (SLC) cause the electron and positron beams to be steered off-center in the disk-loaded waveguide accelerator structures. Off-center beams produce wakefields which limit the SLC performance at high beam intensities by causing emittance growth. Here, we present a general method for simultaneously determining quadrupole magnet and BPM offsets using beam trajectory measurements. Results from the application of the method to the SLC linac are described. The alignment precision achieved is approximately 100 μm, which is significantly better than that obtained using optical surveying techniques. 2 refs., 4 figs

  1. Fabrication and Physical Properties of Titanium Nitride/Hydroxyapatite Composites on Polyether Ether Ketone by RF Magnetron Sputtering Technique

    Science.gov (United States)

    Nupangtha, W.; Boonyawan, D.

    2017-09-01

    Titanium nitride (TiN) coatings have been used very successfully in a variety of applications because of their excellent properties, such as the high hardness meaning good wear resistance and also used for covering medical implants. Hydroxyapatite is a bioactive ceramic that contributes to the restoration of bone tissue, which together with titanium nitride may contribute to obtaining a superior composite in terms of mechanical and bone tissue interaction matters. This paper aims to explain how to optimize deposition conditions for films synthesis on PEEK by varying sputtering parameters such as nitrogen flow rate and direction, deposition time, d-s (target-to-substrate distance) and 13.56 MHz RF power. The plasma conditions used to deposit films were monitored by the optical emission spectroscopy (OES). Titanium nitride/Hydroxyapatite composite films were performed by gas mixture with nitrogen and argon ratio of 1:3 and target-to-substrate distance at 8 cm. The gold colour, as-deposited film was found on PEEK with high hardness and higher surface energy than uncoated PEEK. X-ray diffraction characterization study was carried to study the crystal structural properties of these composites.

  2. ELECTRICAL PROPERTIES OF Cr/CrN NANO-MULTILAYERS PRODUCED BY THE UNBALANCED MAGNETRON SPUTTERING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    DIANA MARITZA MARULANDA CARDONA

    2011-01-01

    Full Text Available Peliculas de nitruro de cromo (CrN se han aplicado como recubrimientos protectores contra el desgaste y la corrosion debido a sus excelentes propiedades mecanicas y alta resistencia a la corrosion, y en el campo electronico debido a su baja resistividad. Sin embargo, se ha encontrado que las multicapas que combinan peliculas metal/ceramico podrian mejorar las propiedades en comparacion a sus contrapartes en monocapa debido al aumento e interaccion entre interfaces. En este trabajo se produjeron nano-multicapas de Cr/CrN a traves de la tecnica de sputtering con magnetron desbalanceado con tres grados de desbalanceo diferentes para estudiar la influencia de este parametro en las propiedades electricas. Se crecieron multicapas con un espesor total de aproximadamente 1 microm y un periodo de bicapa (A de 200 nm, 100 nm y 20 nm. Las multicapas se produjeron a temperatura ambiente sobre acero H13 y silicio (100 y se estudio su microestructura y las propiedades electricas en funcion del campo magnetico. La formacion de fases se caracterizo a traves de Difraccion de Rayos X y los resultados muestran las orientaciones (111 y (200 para todas las multicapas. Se obtuvieron imagenes de la seccion transversal a traves de Microscopia Electronica de Barrido y los resultados muestran la formacion de una estructura en multicapas.

  3. Development of plant mutation techniques using ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Si Yong; Park, In Sook; Song, Hi Sup; Kim, Dong Sub; Kim, Soo Yeon

    2006-06-15

    It has been reported that ion beam with high liner energy transfer (LET) show relative high biological effectiveness (RBE) and more effective for induced plant mutation than low LET radiation i.e., X-rays, gamma rays and electrons. This study was conducted to induce mutation of in vitro cultured orchid and Chrysanthemum using proton beam of the MC-50 cyclotron (50 MeV) at the Korea Institute of Radiological and Medical Science. In vitro cultured stems of chrysanthemum(cv. Migok) and protocom-like bodies(PLBs) of Dendrobium orchid (cv. Kingianum) placed in the plastic petridish (5.5cm in diameter) with agar medium were irradiated by the proton beam with various dose ranges of 10, 25, 50, 100 Gy under the condition of 5nA beam current. Those irradiated plants were transferred to subculture media and then investigated growth characteristics. Shoot growth of chrysanthemum and orchid was decreased by increase of irradiation dose. In particular, new shoot formation was hardly founded over 50Gy in chrysanthemum and 100 Gy in orchid. Some leaf mutants were observed at the 25 Gy and 50 Gy irradiated PLBs of the orchid. The dry seeds of hot pepper, rapeseed, rice and perilla also were irradiated with proton beam of MC-50 cyclotron and then measured germination rate and early growth of M1 plants compared with gamma ray irradiation.

  4. Development of plant mutation techniques using ion beam

    International Nuclear Information System (INIS)

    Kang, Si Yong; Park, In Sook; Song, Hi Sup; Kim, Dong Sub; Kim, Soo Yeon

    2006-06-01

    It has been reported that ion beam with high liner energy transfer (LET) show relative high biological effectiveness (RBE) and more effective for induced plant mutation than low LET radiation i.e., X-rays, gamma rays and electrons. This study was conducted to induce mutation of in vitro cultured orchid and Chrysanthemum using proton beam of the MC-50 cyclotron (50 MeV) at the Korea Institute of Radiological and Medical Science. In vitro cultured stems of chrysanthemum(cv. Migok) and protocom-like bodies(PLBs) of Dendrobium orchid (cv. Kingianum) placed in the plastic petridish (5.5cm in diameter) with agar medium were irradiated by the proton beam with various dose ranges of 10, 25, 50, 100 Gy under the condition of 5nA beam current. Those irradiated plants were transferred to subculture media and then investigated growth characteristics. Shoot growth of chrysanthemum and orchid was decreased by increase of irradiation dose. In particular, new shoot formation was hardly founded over 50Gy in chrysanthemum and 100 Gy in orchid. Some leaf mutants were observed at the 25 Gy and 50 Gy irradiated PLBs of the orchid. The dry seeds of hot pepper, rapeseed, rice and perilla also were irradiated with proton beam of MC-50 cyclotron and then measured germination rate and early growth of M1 plants compared with gamma ray irradiation

  5. Dense and high-stability Ti2AlN MAX phase coatings prepared by the combined cathodic arc/sputter technique

    Science.gov (United States)

    Wang, Zhenyu; Liu, Jingzhou; Wang, Li; Li, Xiaowei; Ke, Peiling; Wang, Aiying

    2017-02-01

    Ti2AlN belongs to a family of ternary nano-laminate alloys known as the MAX phases, which exhibit a unique combination of metallic and ceramic properties. In the present work, the dense and high-stability Ti2AlN coating has been successfully prepared through the combined cathodic arc/sputter deposition, followed by heat post-treatment. It was found that the as-deposited Ti-Al-N coating behaved a multilayer structure, where (Ti, N)-rich layer and Al-rich layer grew alternately, with a mixed phase constitution of TiN and TiAlx. After annealing at 800 °C under vacuum condition for 1.5 h, although the multilayer structure still was found, part of multilayer interfaces became indistinct and disappeared. In particular, the thickness of the Al-rich layer decreased in contrast to that of as-deposited coating due to the inner diffusion of the Al element. Moreover, the Ti2AlN MAX phase emerged as the major phase in the annealed coatings and its formation mechanism was also discussed in this study. The vacuum thermal analysis indicated that the formed Ti2AlN MAX phase exhibited a high-stability, which was mainly benefited from the large thickness and the dense structure. This advanced technique based on the combined cathodic arc/sputter method could be extended to deposit other MAX phase coatings with tailored high performance like good thermal stability, high corrosion and oxidation resistance etc. for the next protective coating materials.

  6. Sputtering calculations with the discrete ordinated method

    International Nuclear Information System (INIS)

    Hoffman, T.J.; Dodds, H.L. Jr.; Robinson, M.T.; Holmes, D.K.

    1977-01-01

    The purpose of this work is to investigate the applicability of the discrete ordinates (S/sub N/) method to light ion sputtering problems. In particular, the neutral particle discrete ordinates computer code, ANISN, was used to calculate sputtering yields. No modifications to this code were necessary to treat charged particle transport. However, a cross section processing code was written for the generation of multigroup cross sections; these cross sections include a modification to the total macroscopic cross section to account for electronic interactions and small-scattering-angle elastic interactions. The discrete ordinates approach enables calculation of the sputtering yield as functions of incident energy and angle and of many related quantities such as ion reflection coefficients, angular and energy distributions of sputtering particles, the behavior of beams penetrating thin foils, etc. The results of several sputtering problems as calculated with ANISN are presented

  7. Techniques to produce and accelerate radioactive ion beams

    CERN Document Server

    Penescu, Liviu Constantin; Lettry, Jacques; Cata-Danil, Gheorghe

    The production and acceleration of the Radioactive Ion Beams (RIB) continues the long line of nuclear investigations started in the XIXth century by Pierre and Marie Curie, Henri Becquerel and Ernest Rutherford. The contemporary applications of the RIBs span a wide range of physics fields: nuclear and atomic physics, solid-state physics, life sciences and material science. ISOLDE is a world-leading Isotope mass-Separation On-Line (ISOL) facility hosted at CERN in Geneva for more than 40 years, offering the largest variety of radioactive ion beams with, until now, more than 1000 isotopes of more than 72 elements (with Z ranging from 2 to 88), with half-lives down to milliseconds and intensities up to 1011 ions/s. The post acceleration of the full variety of beams allows reaching final energies between 0.8 and 3.0 MeV/u. This thesis describes the development of a new series of FEBIAD (“Forced Electron Beam Induced Arc Discharge”) ion sources at CERN-ISOLDE. The VADIS (“Versatile Arc Discharge Ion Source�...

  8. 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.

  9. Convergent beam electron diffraction – A novel technique for ...

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    The subsequent development of STEM units made it possible to obtain finer probes with ... inability to identify the position of atoms in a unit cell, was completely eliminated by ... CBED patterns in the first attempt to measure structural factors using ... Gjonnes & Hoier (1971) analysed this effect based on the three-beam theory.

  10. Arrays of Size-Selected Metal Nanoparticles Formed by Cluster Ion Beam Technique

    DEFF Research Database (Denmark)

    Ceynowa, F. A.; Chirumamilla, Manohar; Zenin, Volodymyr

    2018-01-01

    Deposition of size-selected copper and silver nanoparticles (NPs) on polymers using cluster beam technique is studied. It is shown that ratio of particle embedment in the film can be controlled by simple thermal annealing. Combining electron beam lithography, cluster beam deposition, and heat...... with required configurations which can be applied for wave-guiding, resonators, in sensor technologies, and surface enhanced Raman scattering....

  11. Improving optical properties of silicon nitride films to be applied in the middle infrared optics by a combined high-power impulse/unbalanced magnetron sputtering deposition technique.

    Science.gov (United States)

    Liao, Bo-Huei; Hsiao, Chien-Nan

    2014-02-01

    Silicon nitride films are prepared by a combined high-power impulse/unbalanced magnetron sputtering (HIPIMS/UBMS) deposition technique. Different unbalance coefficients and pulse on/off ratios are applied to improve the optical properties of the silicon nitride films. The refractive indices of the Si3N4 films vary from 2.17 to 2.02 in the wavelength ranges of 400-700 nm, and all the extinction coefficients are smaller than 1×10(-4). The Fourier transform infrared spectroscopy and x-ray diffractometry measurements reveal the amorphous structure of the Si3N4 films with extremely low hydrogen content and very low absorption between the near IR and middle IR ranges. Compared to other deposition techniques, Si3N4 films deposited by the combined HIPIMS/UBMS deposition technique possess the highest refractive index, the lowest extinction coefficient, and excellent structural properties. Finally a four-layer coating is deposited on both sides of a silicon substrate. The average transmittance from 3200 to 4800 nm is 99.0%, and the highest transmittance is 99.97% around 4200 nm.

  12. Beam shaping optics to enhance performance of interferometry techniques in grating manufacture

    Science.gov (United States)

    Laskin, Alexander; Laskin, Vadim; Ostrun, Aleksei

    2018-02-01

    Improving of industrial holographic and interferometry techniques is of great importance in interference lithography, computer-generated holography, holographic data storage, interferometry recording of Bragg gratings as well as gratings of various types in semiconductor industry. Performance of mentioned techniques is essentially enhanced by providing a light beam with flat phase front and flat-top irradiance distribution. Therefore, transformation of Gaussian distribution of a TEM00 laser to flat-top (top hat, uniform) distribution is an important optical task. 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. As a solution it is suggested to apply refractive field mapping beam shaping optics πShaper, 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. High optical quality of resulting flat-top beam allows applying additional optical components to build various imaging optical systems for variation of beam size and shape to fulfil requirements of a particular application. This paper will describe design basics of refractive beam shapers and optical layouts of their applying in holography and laser interference lithography. Examples of real implementations and experimental results will be presented as well.

  13. Isotope puzzle in sputtering

    International Nuclear Information System (INIS)

    Zheng Liping

    1998-01-01

    Mechanisms affecting multicomponent material sputtering are complex. Isotope sputtering is the simplest in the multicomponent materials sputtering. Although only mass effect plays a dominant role in the isotope sputtering, there is still an isotope puzzle in sputtering by ion bombardment. The major arguments are as follows: (1) At the zero fluence, is the isotope enrichment ejection-angle-independent or ejection-angle-dependent? (2) Is the isotope angular effect the primary or the secondary sputter effect? (3) How to understand the action of momentum asymmetry in collision cascade on the isotope sputtering?

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

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S. Y. [Indiana Univ., Bloomington, IN (United States)

    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.

  15. Laser fluorescence spectroscopy of sputtered uranium atoms

    International Nuclear Information System (INIS)

    Wright, R.B.; Pellin, M.J.; Gruen, D.M.; Young, C.E.

    1979-01-01

    Laser induced fluorescence (LIF) spectroscopy was used to study the sputtering of 99.8% 238 U metal foil when bombarded by normally incident 500 to 3000 eV Ne + , Ar + , Kr + , and O 2 + . A three-level atom model of the LIF processes is developed to interpret the observed fluorescent emission from the sputtered species. The model shows that close attention must be paid to the conditions under which the experiment is carried out as well as to the details of the collision cascade theory of sputtering. Rigorous analysis shows that when properly applied, LIF can be used to investigate the predictions of sputtering theory as regards energy distributions of sputtered particles and for the determination of sputtering yields. The possibility that thermal emission may occur during sputtering can also be tested using the proposed model. It is shown that the velocity distribution (either the number density or flux density distribution, depending upon the experimental conditions) of the sputtered particles can be determined using the LIF technique and that this information can be used to obtain a description of the basic sputtering mechanisms. These matters are discussed using the U-atom fluorescence measurements as a basis. The relative sputtering yields for various incident ions on uranium were also measured for the first time using the LIF technique. A surprisingly high fraction of the sputtered uranium atoms were found to occupy the low lying metastable energy levels of U(I). The population of the sputtered metastable atoms were found approximately to obey a Boltzman distribution with an effective temperature of 920 +- 100 0 K. 41 references

  16. Ion-beam technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R. [Argonne National Lab., IL (United States)

    1993-01-01

    This compilation of figures and diagrams reviews processes for depositing diamond/diamond-like carbon films. Processes addressed are chemical vapor deposition (HFCVD, PACVD, etc.), plasma vapor deposition (plasma sputtering, ion beam sputtering, evaporation, etc.), low-energy ion implantation, and hybrid processes (biased sputtering, IBAD, biased HFCVD, etc.). The tribological performance of coatings produced by different means is discussed.

  17. Applied dosimetry to ionization techniques by electron beams

    International Nuclear Information System (INIS)

    Kuntz, F.

    1991-12-01

    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

  18. Friction of self-lubricating surfaces by ion beam techniques. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, R.S.; Rai, A.K.

    1992-05-01

    UES, Inc. conducted a research and development program designed to establish conditions for ion implantation/mixing of suitable additives into the surfaces of bulk ceramics and metals for obtaining self-lubricating low friction and wear characteristics. The substrates considered were ZrO{sub 2}, Al{sub 2}O{sub 3}, Si{sub 3}N{sub 4}, steel and Ni-base superalloy. The lubricant additives chosen were BaF{sub 2}/CaF{sub 2}Ag, MoS{sub 2}, WS{sub 2}and B{sub 2}O{sub 3}. The initial tasks of the program were to synthesis these lubricant compounds by co-implantation of constituent elements if sufficient beams of desired elements were obtained. The final tasks were to investigate high energy (MeV) ion mixing of deposited coatings as well as to investigate ion beam assisted deposition using low energy ion beams. It was shown that MoS{sub 2} can be synthesized by co-implantation of Mo{sup +} and S{sup +} in ceramic materials with appropriate choice of energies to obtain nearly overlapping depth profiles. The sliding life of DC magnetron sputtered MoS{sub 2} films of thicknesses {approximately}7500{Angstrom} on ceramic materials such as sapphire, Si{sub 3}N{sub 4} and ZrO{sub 3} were improved by ten to thousand fold after 2 Mev Ag{sup +} ion mixing. Ion beam assisted deposition (IBAD) and ion beam mixing were utilized to fabricate self-lubricating coatings of CaF{sub 2}/Ag and BaF/CaF{sub 2}/Ag composites.

  19. 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)

  20. A new crossed molecular beam apparatus using time-sliced ion velocity imaging technique

    International Nuclear Information System (INIS)

    Wu Guorong; Zhang Weiqing; Pan Huilin; Shuai Quan; Jiang Bo; Dai Dongxu; Yang Xueming

    2008-01-01

    A new crossed molecular beam apparatus has been constructed for investigating polyatomic chemical reactions using the time-sliced ion velocity map imaging technique. A unique design is adopted for one of the two beam sources and allows us to set up the molecular beam source either horizontally or vertically. This can be conveniently used to produce versatile atomic or radical beams from photodissociation and as well as electric discharge. Intensive H-atom beam source with high speed ratio was produced by photodissociation of the HI molecule and was reacted with the CD 4 molecule. Vibrational-state resolved HD product distribution was measured by detecting the CD 3 product. Preliminary results were also reported on the F+SiH 4 reaction using the discharged F atom beam. These results demonstrate that this new instrument is a powerful tool for investigating chemical dynamics of polyatomic reactions.

  1. Soft X-ray beam induced current technique

    Energy Technology Data Exchange (ETDEWEB)

    Watts, B; Ade, H [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Queen, D; Hellman, F [Department of Physics, University of California, Berkeley, CA 94720 (United States); Kilcoyne, A L D; Tyliszczak, T, E-mail: benjamin.watts@gmail.co [Advanced Light Source, Lawrence Berkeley Nat. Lab., Berkeley, CA 94720 (United States)

    2009-09-01

    Direct mapping of the charge transport efficiency of polymer solar cell devices using a soft X-ray beam induced current (SoXBIC) method is described. By fabricating a polymer solar cell on an x-ray transparent substrate, we demonstrate the ability to map polymer composition and nanoscale structure within an operating solar cell device and to simultaneously measure the local charge transport efficiency via the short-circuit current. A simple model is calculated and compared to experimental SoXBIC data of a PFB:F8BT bulk-heterojunction device in order to gain greater insight into the device operation and physics.

  2. A Retrofit Technique for Kicker Beam-Coupling Impedance Reduction

    CERN Document Server

    Caspers, Friedhelm; Kroyer, T; Timmins, M; Uythoven, J; Kurennoy, S

    2004-01-01

    The reduction of the impedance of operational ferrite kicker structures may be desirable in order to avoid rebuilding such a device. Often resistively coated ceramic plates or tubes are installed for this purpose but at the expense of available aperture. Ceramic U-shaped profiles with a resistive coating fitting between the ellipse of the beam and the rectangular kicker aperture have been used to significantly reduce the impedance of the magnet, while having a limited effect on the available physical aperture. Details of this method, constraints, measurements and simulation results as well as practical aspects are presented and discussed.

  3. The beam based alignment technique for the measurements of beam position monitors offsets and beam offsets from quadrupoles in the Pohang Light Source

    International Nuclear Information System (INIS)

    Kim, K.H.; Huang, J.Y.; Ko, I.S.

    1999-01-01

    The beam based alignment (BBA) technique is applied to the 2-GeV storage ring of the Pohang Light Source to measure the offsets of beam position monitors. This measurement is particularly necessary for beam position monitors (BPMs) plugged into a long (∼10 m) aluminum chamber, since the mechanical deformation of the vacuum chamber is experienced after repeated heating for the outgassing process, and the BPM positions are changed accordingly. A part of the excitation current of each quadrupole magnet is shunted through an electronic shunt circuit. Then, the closed orbit receives a perturbation due to the current reduction. Using two quadrupole magnets, we can measure the offset of each BPM. Also, the BBA technique is applied to measure the beam offsets from the center of quadrupole magnets, and gives information to the survey team about which quadrupole magnets should be aligned mostly. In this process, we introduce the merit function to reduce various errors such as BPM characteristic changes and the lattice imperfection. By minimizing the merit function, we can get the beam offset as the maximized expectation value. This paper presents the BBA technique used and experimental results taken from the 2-GeV Pohang Light Source (PLS) storage ring. When the BPM offset is measured, it is observed that a 3% of the shunt current is suitable. (author)

  4. Low-Damage Sputter Deposition on Graphene

    Science.gov (United States)

    Chen, Ching-Tzu; Casu, Emanuele; Gajek, Marcin; Raoux, Simone

    2013-03-01

    Despite its versatility and prevalence in the microelectronics industry, sputter deposition has seen very limited applications for graphene-based electronics. We have systematically investigated the sputtering induced graphene defects and identified the reflected high-energy neutrals of the sputtering gas as the primary cause of damage. In this talk, we introduce a novel sputtering technique that is shown to dramatically reduce bombardment of the fast neutrals and improve the structural integrity of the underlying graphene layer. We also demonstrate that sputter deposition and in-situ oxidation of 1 nm Al film at elevated temperatures yields homogeneous, fully covered oxide films with r.m.s. roughness much less than 1 monolayer, which shows the potential of using such technique for gate oxides, tunnel barriers, and multilayer fabrication in a wide range of graphene devices.

  5. Techniques for evaluation of E-beam evaporative processes

    International Nuclear Information System (INIS)

    Meier, T.C.; Nelson, C.M.

    1996-01-01

    High dynamic range video imaging of the molten pool surface has provided insight regarding process responses at the melt pool liquid-vapor interface. A water-cooled video camera provides continuous high resolution imaging of the pool surface from a low angle position within 20 cm of the liquid-vapor interface. From the vantage point, the e-beam footprint is clearly defined and melt pool free surface shape can be observed. Effects of changes in a beam footprint, power distribution, and sweep frequency on pool surface shape and stability of vaporization are immediately shown. Other events observed and recorded include: formation of the pool and dissipation of ''rafts'' on the pool surface during startup, behavior of feed material as it enters the pool, effects of feed configuration changes on mixing of feed entering the pool volume and behaviors of co-evaporated materials of different vapor pressures at the feed/pool boundary. When used in conjunction with laser vapor monitoring, correlation between pool surface phenomena and vaporizer performance has been identified. This video capability was used in verifying the titanium evaporation model results presented at this conference by confirming the calculated melt pool surface deformations caused by vapor pressure of the departing evaporant at the liquid-vapor interface

  6. Techniques for evaluation of E-beam evaporative processes

    Energy Technology Data Exchange (ETDEWEB)

    Meier, T.C.; Nelson, C.M.

    1996-10-01

    High dynamic range video imaging of the molten pool surface has provided insight regarding process responses at the melt pool liquid-vapor interface. A water-cooled video camera provides continuous high resolution imaging of the pool surface from a low angle position within 20 cm of the liquid-vapor interface. From the vantage point, the e-beam footprint is clearly defined and melt pool free surface shape can be observed. Effects of changes in a beam footprint, power distribution, and sweep frequency on pool surface shape and stability of vaporization are immediately shown. Other events observed and recorded include: formation of the pool and dissipation of ``rafts`` on the pool surface during startup, behavior of feed material as it enters the pool, effects of feed configuration changes on mixing of feed entering the pool volume and behaviors of co-evaporated materials of different vapor pressures at the feed/pool boundary. When used in conjunction with laser vapor monitoring, correlation between pool surface phenomena and vaporizer performance has been identified. This video capability was used in verifying the titanium evaporation model results presented at this conference by confirming the calculated melt pool surface deformations caused by vapor pressure of the departing evaporant at the liquid-vapor interface.

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

    International Nuclear Information System (INIS)

    McCormick, B.; Ellsworth, R.; Abramson, D.; Haik, B.; Tome, M.; Grabowski, E.; LoSasso, T.

    1988-01-01

    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

  8. Tool steel ion beam assisted nitrocarburization

    International Nuclear Information System (INIS)

    Zagonel, L.F.; Alvarez, F.

    2007-01-01

    The nitrocarburization of the AISI-H13 tool steel by ion beam assisted deposition is reported. In this technique, a carbon film is continuously deposited over the sample by the ion beam sputtering of a carbon target while a second ion source is used to bombard the sample with low energy nitrogen ions. The results show that the presence of carbon has an important impact on the crystalline and microstructural properties of the material without modification of the case depth

  9. Investigations on structural and electrical parameters of p-Si/ MgxZn1-xO thin film heterojunction diodes grown by RF magnetron sputtering technique

    Science.gov (United States)

    Singh, Satyendra Kumar; Hazra, Purnima

    2018-05-01

    This work reports fabrication and characterization of p-Si/ MgxZn1-xO thin film heterojunction diodes grown by RF magnetron sputtering technique. In this work, ZnO powder was mixed with MgO powder at per their weight percentage from 0 to 10% to prepare MgxZn1-xO target. The microstructural, surface morphological and optical properties of as-deposited p-Si/MgxZn1-xO heterostructure thin films have been studied using X-ray Diffraction, atomic force microscopy and variable angle ellipsometer. XRD spectra exhibit that undoped ZnO thin films has preferred crystal orientation in (002) plane. However, with increase in Mg-doping, ZnO (101) crystal plane is enhanced progressively due to phase segregation, even though preferred growth orientation of ZnO crystals is still towards (002) plane. The electrical characteristics of Si/ MgxZn1-xO heterojunction diodes with large area Al/Ti ohmic contacts are evaluated using semiconductor parameter analyzer. With rectification ratio of 27894, reverse saturation current of 20.5 nA and barrier height of 0.724 eV, Si/Mg0.5Zn0.95O thin film heterojunction diode is believed to have potential to be used in wider bandgap nanoelectronic device applications.

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

    International Nuclear Information System (INIS)

    Rampado, O.

    2014-01-01

    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.

  11. Technique for measuring charged particle distribution in a pulsed beam. Sposob izmereniya raspredeleniya zaryazhennykh chastits v impul'snom puchke

    Energy Technology Data Exchange (ETDEWEB)

    Zakutin, V V; Shenderovich, A M

    1988-11-07

    Technique for measuring charged particle distribution in a pulsed beam by producing beam imprint on a target is described. In order to measure beam particle distribution in longitudinal direction, all beam particles are deflected simultaneously to the target, located in parallel with initial direction of beam motion, by transverse pulse magnetic field, homogeneous in the field of trajectories of beam particle motion in the field. The invention enables to conduct measurements of longitudinal distribution of particle density in beams of 10{sup -9}-10{sup -11}s duration, this corresponds to longitudinal beam dimensions from 30 cm down to 3 mm. 1 fig.

  12. Fabrication and characterization of He-charged ODS-FeCrNi films deposited by a radio-frequency plasma magnetron sputtering technique

    Science.gov (United States)

    Song, Liang; Wang, Xianping; Wang, Le; Zhang, Ying; Liu, Wang; Jiang, Weibing; Zhang, Tao; Fang, Qianfeng; Liu, Changsong

    2017-04-01

    He-charged oxide dispersion strengthened (ODS) FeCrNi films were prepared by a radio-frequency (RF) plasma magnetron sputtering method in a He and Ar mixed atmosphere at 150 °C. As a comparison, He-charged FeCrNi films were also fabricated at the same conditions through direct current (DC) plasma magnetron sputtering. The doping of He atoms and Y2O3 in the FeCrNi films was realized by the high backscattered rate of He ions and Y2O3/FeCrNi composite target sputtering method, respectively. Inductive coupled plasma (ICP) and x-ray photoelectron spectroscopy (XPS) analysis confirmed the existence of Y2O3 in FeCrNi films, and Y2O3 content hardly changed with sputtering He/Ar ratio. Cross-sectional scanning electron microscopy (SEM) shows that the FeCrNi films were composed of dense columnar nanocrystallines and the thickness of the films was obviously dependent on He/Ar ratio. Nanoindentation measurements revealed that the FeCrNi films fabricated through DC/RF plasma magnetron sputtering methods exhibited similar hardness values at each He/Ar ratio, while the dispersion of Y2O3 apparently increased the hardness of the films. Elastic recoil detection (ERD) showed that DC/RF magnetron sputtered FeCrNi films contained similar He amounts (˜17 at.%). Compared with the minimal change of He level with depth in DC-sputtered films, the He amount decreases gradually in depth in the RF-sputtered films. The Y2O3-doped FeCrNi films were shown to exhibit much smaller amounts of He owing to the lower backscattering possibility of Y2O3 and the inhibition effect of nano-sized Y2O3 particles on the He element.

  13. Ion-induced sputtering

    International Nuclear Information System (INIS)

    Yamamura, Yasumichi; Shimizu, Ryuichi; Shimizu, Hazime; Ito, Noriaki.

    1983-01-01

    The research on ion-induced sputtering has been continued for a long time, since a hundred or more years ago. However, it was only in 1969 by Sigmund that the sputtering phenomena were theoretically arranged into the present form. The reason why the importance of sputtering phenomena have been given a new look recently is the application over wide range. This paper is a review centering around the mechanism of causing sputtering and its characteristics. Sputtering is such a phenomenon that the atoms in the vicinity of a solid surface are emitted into vacuum by receiving a part of ion energy, or in other words, it is a kind of irradiation damage in the vicinity of a solid surface. In this meaning, it can be considered that the sputtering based on the ions located on the clean surface of a single element metal is simple, and has already been basically understood. On the contrary, the phenomena can not be considered to be fully understood in the case of alloys and compounds, because these surface conditions under irradiation are not always clear due to segregation and others. In the paper, the physical of sputtering, single element sputtering, the sputtering in alloys and compounds, and the behaviour of emitted particles are explained. Finally, some recent topics of the sputtering measurement by laser resonant excitation, the sputtering by electron excitation, chemical sputtering, and the sputtering in nuclear fusion reactors are described. (Wakatsuki, Y.)

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

    International Nuclear Information System (INIS)

    Comins, J.D.; Amolo, G.O.; Derry, T.E.; Connell, S.H.; Erasmus, R.M.; Witcomb, M.J.

    2009-01-01

    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 3 crystals implanted with 8 MeV Au 3+ ions with a fluence of 1 x 10 17 ions/cm 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 3 - 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 3 - and I 5 - 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 17 ions/cm 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 15 to 250 x 10 15 ions/cm -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 also high fluence optical absorption studies. X-ray diffraction studies show

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

    Science.gov (United States)

    Comins, J. D.; Amolo, G. O.; Derry, T. E.; Connell, S. H.; Erasmus, R. M.; Witcomb, M. J.

    2009-08-01

    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 3 crystals implanted with 8 MeV Au 3+ ions with a fluence of 1 × 10 17 ions/cm 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 I3- 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 I3- and I5- 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 × 10 17 ions/cm 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 × 10 15 to 250 × 10 15 ions/cm -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 also high fluence optical absorption studies. X-ray diffraction studies show

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

    International Nuclear Information System (INIS)

    Yamamoto, Setsu; Miura, Takahiro; Semboshi, Jun; Ochiai, Makoto; Mitsuhashi, Tadahiro; Adachi, Hiroyuki; Yamamoto, Satoshi

    2013-01-01

    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)

  17. Cutting technique for reactor internals by laser beam

    International Nuclear Information System (INIS)

    Matsumoto, O.; Sugihara, M.; Matsuda, K.; Miya, K.

    1990-01-01

    At present in Japan the verification tests on the commercial nuclear power reactor decommissioning technology are being conducted as the project of The Ministry of International Trade and Industry by Nuclear Power Engineering Test Center. This paper summarizes the interim results of the verification test for the reactor core internals decommissioning technology, which is being conducted from 1986 as a theme of the above project. All core internals to be studied here are made of stainless steel, and the maximum wall thickness is about 500mm (the maximum one to be cut is about 300mm) for the PWR's, and about 100mm for the BWR's. Though the plasma cutting, arc saw cutting method, etc. have been studied u p to now as the cutting technology for decommissioning these core internals, the authors are carrying out the development and verification test of the cutting technology with the laser beam, which is expected to increase its power in future and can be applied to various materials

  18. Ion beam sputtering and depth profiling: on the characteristics of the induced roughness and the means to cure it at best

    International Nuclear Information System (INIS)

    Limoge, Y.; Maurice, F.; Zemskoff, A.

    1987-01-01

    The purpose of the present communication is to report the first results of a study devoted to the understanding of the surface roughness due either to statistical fluctuations in sputtering or sample microstructural inhomogeneities. In a second part, we shall propose a new method to correct the experimental profiles from the blurring effect of the sample roughness in typical cases of in-depth analysis

  19. A calculation technique of passing of a powerful relativistic beam through substance

    International Nuclear Information System (INIS)

    Pobitko, A.I.; Sal'nikov, L.I.; Sukhovitskij, E.Sh.

    1995-01-01

    The calculation algorithm of passing powerful relativistic beam through substance is developed. Algorithm of calculation is separated on the following problems: 1) a trial charge movement in electromagnetic field of the cylindrical geometry; 2) a computing of own electromagnetic field arising at movement of a particle heavy-current beam in a target; 3) accounting of an interaction of a beam with target atoms; 4) accounting of change of the target properties in a time; 5) geometry and construction of an iterative procedure of calculation. The calculation of passing heavy-current beams of charged particles for transient case is carried out by Monte Carlo method. A conclusion of equations of movement trial charge and technique of calculation own electromagnetic field of the powerful relativistic beam at passing through substance are resulted. 6 refs

  20. A novel approach for the characterization of a bilayer of phenyl-c71-butyric-acid-methyl ester and pentacene using ultraviolet photoemission spectroscopy and argon gas cluster ion beam sputtering process

    International Nuclear Information System (INIS)

    Yun, Dong-Jin; Chung, JaeGwan; Jung, Changhoon; Chung, Yeonji; Kim, SeongHeon; Lee, Seunghyup; Kim, Ki-Hong; Han, Hyouksoo; Park, Gyeong-Su; Park, SungHoon

    2013-01-01

    The material arrangement and energy level alignment of an organic bilayer comprising of phenyl-c71-butyric-acid-methyl ester (PCBM-71) and pentacene were studied using ultraviolet photoelectron spectroscopy (UPS) and the argon gas cluster ion beam (GCIB) sputtering process. Although there is a small difference in the full width at half maximum of the carbon C 1s core level peaks and differences in the oxygen O 1s core levels of an X-ray photoemission spectroscopy spectra, these differences are insufficient to clearly distinguish between PCBM-71 and pentacene layers and to classify the interface and bulk regions. On the other hand, the valence band structures in the UPS spectra contain completely distinct configurations for the PCBM-71 and pentacene layers, even when they have similar atomic compositions. According to the valence band structures of the PCBM-71/pentacene/electrodes, the highest unoccupied molecular orbital (HOMO) region of pentacene is at least 0.8 eV closer to the Fermi level than that of PCBM-71 and it does not overlap with any of the chemical states in the valence band structure of PCBM-71. Therefore, by just following the variations in the area of the HOMO region of pentacene, the interface/bulk regions of the PCBM/pentacene layers were distinctly categorized. Besides, the variation of valence band structures as a function of the Ar GCIB sputtering time fully corroborated with the surface morphologies observed in the atomic force microscope images. In summary, we believe that the novel approach, which involves UPS analysis in conjunction with Ar GCIB sputtering, can be one of the best methods to characterize the material distribution and energy level alignments of stacks of organic layers

  1. A novel approach for the characterization of a bilayer of phenyl-c71-butyric-acid-methyl ester and pentacene using ultraviolet photoemission spectroscopy and argon gas cluster ion beam sputtering process

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Dong-Jin; Chung, JaeGwan; Jung, Changhoon; Chung, Yeonji; Kim, SeongHeon; Lee, Seunghyup; Kim, Ki-Hong; Han, Hyouksoo; Park, Gyeong-Su; Park, SungHoon [Analytical Science Laboratory of Samsung Advanced Institute of Technology, P.O. Box 14-1, Yongin 446-712 (Korea, Republic of)

    2013-09-07

    The material arrangement and energy level alignment of an organic bilayer comprising of phenyl-c71-butyric-acid-methyl ester (PCBM-71) and pentacene were studied using ultraviolet photoelectron spectroscopy (UPS) and the argon gas cluster ion beam (GCIB) sputtering process. Although there is a small difference in the full width at half maximum of the carbon C 1s core level peaks and differences in the oxygen O 1s core levels of an X-ray photoemission spectroscopy spectra, these differences are insufficient to clearly distinguish between PCBM-71 and pentacene layers and to classify the interface and bulk regions. On the other hand, the valence band structures in the UPS spectra contain completely distinct configurations for the PCBM-71 and pentacene layers, even when they have similar atomic compositions. According to the valence band structures of the PCBM-71/pentacene/electrodes, the highest unoccupied molecular orbital (HOMO) region of pentacene is at least 0.8 eV closer to the Fermi level than that of PCBM-71 and it does not overlap with any of the chemical states in the valence band structure of PCBM-71. Therefore, by just following the variations in the area of the HOMO region of pentacene, the interface/bulk regions of the PCBM/pentacene layers were distinctly categorized. Besides, the variation of valence band structures as a function of the Ar GCIB sputtering time fully corroborated with the surface morphologies observed in the atomic force microscope images. In summary, we believe that the novel approach, which involves UPS analysis in conjunction with Ar GCIB sputtering, can be one of the best methods to characterize the material distribution and energy level alignments of stacks of organic layers.

  2. Simulation of carbon sputtering due to molecular hydrogen impact

    International Nuclear Information System (INIS)

    Laszlo, J.

    1993-01-01

    Simulated results are compared to experimental data on the sputtering yield of carbon due to atomic and to molecular hydrogen impact. The experimental sputtering yields of carbon (graphite) due to low energy hydrogen bombardment have been found to be higher than the simulated ones. Efforts are made to obtain high enough simulated yields by considering the formation of dimer, H 2 and D 2 molecules in the primary beam. The molecular beam model applies full neutralization and full dissociation at the surface. The simulation of sputtering yields of target materials up to Z 2 ≤ 30 is also included for the low primary energy regime for deuterium projectiles. It is found that, although the sputtering yields really tend to increase, the effect of molecule formation in the beam in itself cannot be made responsible for the deviation between measured and simulated sputtering yields. (orig.)

  3. Nuclear techniques using radioactive beams for biophysical studies

    CERN Document Server

    Stachura, Monika Kinga

    Perturbed angular correlation of "-rays (PAC) spectroscopy and nuclear magnetic resonance measured by !-decay (betaNMR) spectroscopy are two very sensitive and, among life-scientists, infrequently encountered nuclear techniques. Both of them belong to the family of hyperfine techniques, which allow for measurements of the interactions of extra-nuclear electromagnetic fields with the nuclear moments. In this way - they can provide useful information about the local structure of the investigated systems. The first part of the work presented here focuses on investigating the fundamental chemistry of heavy metal ion - protein interactions mainly with PAC spectroscopy. A variety of questions concerning both the function of metal ions in natural systems and in synthetic biomolecules on the one hand and the toxic effects of some metal ions on the other were addressed, the results of which are described in four different papers. Paper I is a review article entitled ”Selected applications of perturbed angular correl...

  4. Sputtering of water ice

    International Nuclear Information System (INIS)

    Baragiola, R.A.; Vidal, R.A.; Svendsen, W.; Schou, J.; Shi, M.; Bahr, D.A.; Atteberrry, C.L.

    2003-01-01

    We present results of a range of experiments of sputtering of water ice together with a guide to the literature. We studied how sputtering depends on the projectile energy and fluence, ice growth temperature, irradiation temperature and external electric fields. We observed luminescence from the decay of H(2p) atoms sputtered by heavy ion impact, but not bulk ice luminescence. Radiolyzed ice does not sputter under 3.7 eV laser irradiation

  5. Phase aberrations and beam cleanup techniques in carbon-dioxide laser fusion systems

    International Nuclear Information System (INIS)

    Viswanathan, V.K.

    1981-01-01

    This paper describes the various carbon dioxide laser fusion systems at Los Alamos from the point of view of an optical designer. The types of phase aberrations present in these systems, as well as the beam cleanup techniques that can be used to improve the beam optical quality, are discussed. As this is a review article, some previously published results are also used where relevant

  6. All-optical optoacoustic microscopy based on probe beam deflection technique

    OpenAIRE

    Maswadi, Saher M.; Ibey, Bennett L.; Roth, Caleb C.; Tsyboulski, Dmitri A.; Beier, Hope T.; Glickman, Randolph D.; Oraevsky, Alexander A.

    2016-01-01

    Optoacoustic (OA) microscopy using an all-optical system based on the probe beam deflection technique (PBDT) for detection of laser-induced acoustic signals was investigated as an alternative to conventional piezoelectric transducers. PBDT provides a number of advantages for OA microscopy including (i) efficient coupling of laser excitation energy to the samples being imaged through the probing laser beam, (ii) undistorted coupling of acoustic waves to the detector without the need for separa...

  7. Probe beam deflection technique as acoustic emission directionality sensor with photoacoustic emission source.

    Science.gov (United States)

    Barnes, Ronald A; Maswadi, Saher; Glickman, Randolph; Shadaram, Mehdi

    2014-01-20

    The goal of this paper is to demonstrate the unique capability of measuring the vector or angular information of propagating acoustic waves using an optical sensor. Acoustic waves were generated using photoacoustic interaction and detected by the probe beam deflection technique. Experiments and simulations were performed to study the interaction of acoustic emissions with an optical sensor in a coupling medium. The simulated results predict the probe beam and wavefront interaction and produced simulated signals that are verified by experiment.

  8. Possible applications of the ion beams technique for investigations in the field of equation of state

    International Nuclear Information System (INIS)

    Kanel, G.I.; Fortov, V.E.; Baumung, K.; Bluhm, H.

    1998-01-01

    The shock wave generation through the interaction of a high-power ion beam with condensed targets is considered with a goal to reveal possible ways to study the equations of state of matter using ion beams. The equation of state is thought about in an extended interpretation including the relaxation processes, such as phase transitions, chemical reactions, and stress relaxation. Advantages of the beam-driven generation of the high-energy states and possible areas of competition with more conventional technique are discussed. (orig.)

  9. Vietnam Project For Production Of Radioactive Beam Based On ISOL Technique With The Dalat Reactor

    International Nuclear Information System (INIS)

    Le Hong Khiem; Phan Viet Cuong; Fadi Ibrahim

    2011-01-01

    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 235 U 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)

  10. Sputtered indium-tin oxide/cadmium telluride junctions and cadmium telluride surfaces

    International Nuclear Information System (INIS)

    Courreges, F.G.; Fahrenbruch, A.L.; Bube, R.H.

    1980-01-01

    The properties of indium-tin oxide (ITO)/CdTe junction solar cells prepared by rf sputtering of ITO on P-doped CdTe single-crystal substrates have been investigated through measurements of the electrical and photovoltaic properties of ITO/CdTe and In/CdTe junctions, and of electron beam induced currents (EBIC) in ITO/CdTe junctions. In addition, surface properties of CdTe related to the sputtering process were investigated as a function of sputter etching and thermal oxidation using the techniques of surface photovoltage and photoluminescence. ITO/CdTe cells prepared by this sputtering method consist of an n + -ITO/n-CdTe/p-CdTe buried homojunction with about a 1-μm-thick n-type CdTe layer formed by heating of the surface of the CdTe during sputtering. Solar efficiencies up to 8% have been observed with V/sub 0c/=0.82 V and J/sub s/c=14.5 mA/cm 2 . The chief degradation mechanism involves a decrease in V/sub 0c/ with a transformation of the buried homojunction structure to an actual ITO/CdTe heterojunction

  11. Quantification of EFTEM elemental maps using ion beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, J.K.N. [Institut fuer Physik, Universitaet Augsburg, 86135 Augsburg (Germany)]. E-mail: lindner@physik.uni-augsburg.de; Haeberlen, M. [Institut fuer Physik, Universitaet Augsburg, 86135 Augsburg (Germany); Schwarz, F. [Institut fuer Physik, Universitaet Augsburg, 86135 Augsburg (Germany); AxynTeC Duennschichttechnik GmbH, Am Mittleren Moos 49, 86167 Augsburg (Germany); Thorwarth, G. [Institut fuer Physik, Universitaet Augsburg, 86135 Augsburg (Germany); AxynTeC Duennschichttechnik GmbH, Am Mittleren Moos 49, 86167 Augsburg (Germany); Stritzker, B. [Institut fuer Physik, Universitaet Augsburg, 86135 Augsburg (Germany); Hammerl, C. [AxynTeC Duennschichttechnik GmbH, Am Mittleren Moos 49, 86167 Augsburg (Germany); Assmann, W. [Sektion Physik der LMU Muenchen, Am Coulombwall 6, 85748 Garching (Germany)

    2006-08-15

    In this paper the nanometric spatial resolution capabilities of energy filtered cross-sectional transmission electron microscopy (EFTEM) element mapping are complemented with the ability of elastic recoil detection analysis (ERDA) and Rutherford backscattering spectroscopy (RBS) to perform absolute and standardless composition analysis of light and heavy elements. The strength of this combination of techniques is examplified by means of several {mu}m thick multielemental wear protection multilayer stacks of diamond-like carbon (DLC) and silicon compounds with individual sublayers of few ten nanometer thickness, which were analysed with respect to their composition. The result are quantitative high-resolution 2-dimensional distributions of different elements in the several {mu}m thick film sandwiches.

  12. Improvements in technique for determining the surfactant penetration in hair fibres using scanning ion beam analyses

    International Nuclear Information System (INIS)

    Hollands, R.; Clough, A.S.; Meredith, P.

    1999-01-01

    The penetration abilities of surfactants need to be known by companies manufacturing hair-care products. In this work three complementary techniques were used simultaneously - PIXE, NRA and RBS - to measure the penetration of a surfactant, which had been deuterated, into permed hair fibres. Using a scanning micro-beam of 2 MeV 3 He ions 2-dimensional concentration maps were obtained which showed whether the surfactant penetrated the fibre or just stayed on the surface. This is the first report of the use of three simultaneous scattering techniques with a scanning micro-beam. (author)

  13. A beam-based alignment technique for correction of accelerator structure misalignments

    International Nuclear Information System (INIS)

    Kubo, K.; Raubenheimer, T.O.

    1994-08-01

    This paper describes a method of reducing the transverse emittance dilution in linear colliders due to transverse wakefields arising-from misaligned accelerator structures. The technique is a generalization of the Wake-Free correction algorithm. The structure alignment errors are measured locally by varying the bunch charge and/or bunch length and measuring the change in the beam trajectory. The misalignments can then be corrected by varying the beam trajectory or moving structures. The results of simulations are presented demonstrating the viability of the technique

  14. In situ study of interface reactions of ion beam sputter deposited (Ba0.5Sr0.5)TiO3 films on Si, SiO2, and Ir

    International Nuclear Information System (INIS)

    Gao, Y.; Mueller, A.H.; Irene, E.A.; Auciello, O.; Krauss, A.; Schultz, J.A.

    1999-01-01

    (Ba 0.5 ,Sr 0.5 )TiO 3 (BST) thin films were deposited on MgO, Si, SiO 2 and Ir surfaces by ion beam sputter deposition in oxygen at 700 degree C. In situ spectroscopic ellipsometry (SE) has been used to investigate the evolution of the BST films on different surfaces during both deposition and postannealing processes. First, the optical constants of the BST films in the photon energy range of 1.5 - 4.5 eV were determined by SE analysis on crystallized BST films deposited on MgO single crystal substrates. The interfaces in BST/Si and BST/SiO 2 /Si structure were examined by SE and Auger electron spectroscopy depth profiles. Subcutaneous oxidation in the BST/Ir structure was observed by in situ SE during both ion beam sputter deposition and postdeposition annealing in oxygen at 700 degree C. A study of the thermal stability of the Ir/TiN/SiO 2 /Si structure in oxygen at 700 degree C was carried out using in situ SE. The oxidation of Ir was confirmed by x-ray diffraction. The surface composition and morphology evolution after oxidation were investigated by time of flight mass spectroscopy of recoiled ions (TOF-MSRI) and atomic force microscopy. It has been found that Ti from the underlying TiN barrier layer diffused through the Ir layer onto the surface and thereupon became oxidized. It was also shown that the surface roughness increases with increasing oxidation time. The implications of the instability of Ir/TiN/SiO 2 /Si structure on the performance of capacitor devices based on this substrate are discussed. It has been shown that a combination of in situ SE and TOF-MSRI provides a powerful methodology for in situ monitoring of complex oxide film growth and postannealing processes. copyright 1999 American Vacuum Society

  15. Study of SiO2 surface sputtering by a 250-550 keV He+ ion beam during high-resolution Rutherford backscattering measurements

    International Nuclear Information System (INIS)

    Kusanagi, Susumu; Kobayashi, Hajime

    2006-01-01

    Decreases in oxygen signal intensities in spectra of high-resolution Rutherford backscattering spectrometry (HRBS) were observed during measurements on a 5-nm thick SiO 2 layer on a Si substrate when irradiated by 250-550 keV He + ions. Shifts in an implanted arsenic profile in a 5-nm thick SiO 2 /Si substrate were also observed as a result of He + ion irradiation. These results lead to the conclusion that the SiO 2 surface was sputtered by He + ions in this energy range

  16. A hybrid electron cyclotron resonance metal ion source with integrated sputter magnetron for the production of an intense Al{sup +} ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Weichsel, T., E-mail: tim.weichsel@fep.fraunhofer.de; Hartung, U.; Kopte, T. [Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, 01277 Dresden (Germany); Zschornack, G. [Institute of Solid State Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, Dresden (Germany); Kreller, M.; Philipp, A. [DREEBIT GmbH, 01900 Grossroehrsdorf (Germany)

    2015-09-15

    A metal ion source prototype has been developed: a combination of magnetron sputter technology with 2.45 GHz electron cyclotron resonance (ECR) ion source technology—a so called magnetron ECR ion source (MECRIS). An integrated ring-shaped sputter magnetron with an Al target is acting as a powerful metal atom supply in order to produce an intense current of singly charged metal ions. Preliminary experiments show that an Al{sup +} ion current with a density of 167 μA/cm{sup 2} is extracted from the source at an acceleration voltage of 27 kV. Spatially resolved double Langmuir probe measurements and optical emission spectroscopy were used to study the plasma states of the ion source: sputter magnetron, ECR, and MECRIS plasma. Electron density and temperature as well as Al atom density were determined as a function of microwave and sputter magnetron power. The effect of ECR heating is strongly pronounced in the center of the source. There the electron density is increased by one order of magnitude from 6 × 10{sup 9} cm{sup −3} to 6 × 10{sup 10} cm{sup −3} and the electron temperature is enhanced from about 5 eV to 12 eV, when the ECR plasma is ignited to the magnetron plasma. Operating the magnetron at constant power, it was observed that its discharge current is raised from 1.8 A to 4.8 A, when the ECR discharge was superimposed with a microwave power of 2 kW. At the same time, the discharge voltage decreased from about 560 V to 210 V, clearly indicating a higher plasma density of the MECRIS mode. The optical emission spectrum of the MECRIS plasma is dominated by lines of excited Al atoms and shows a significant contribution of lines arising from singly ionized Al. Plasma emission photography with a CCD camera was used to prove probe measurements and to identify separated plasma emission zones originating from the ECR and magnetron discharge.

  17. The edge transient-current technique (E-TCT) with high energy hadron beam

    Energy Technology Data Exchange (ETDEWEB)

    Gorišek, Andrej; Cindro, Vladimir; Kramberger, Gregor; Mandić, Igor [J. Stefan Institute, Ljubljana (Slovenia); Mikuž, Marko [J. Stefan Institute, Ljubljana (Slovenia); University of Ljubljana (Slovenia); Muškinja, Miha; Zavrtanik, Marko [J. Stefan Institute, Ljubljana (Slovenia)

    2016-09-21

    We propose a novel way to investigate the properties of silicon and CVD diamond detectors for High Energy Physics experiments complementary to the already well-established E-TCT technique using laser beam. In the proposed setup the beam of high energy hadrons (MIPs) is used instead of laser beam. MIPs incident on the detector in the direction parallel to the readout electrode plane and perpendicular to the edge of the detector. Such experiment could prove very useful to study CVD diamond detectors that are almost inaccessible for the E-TCT measurements with laser due to large band-gap as well as to verify and complement the E-TCT measurements of silicon. The method proposed is being tested at CERN in a beam of 120 GeV hadrons using a reference telescope with track resolution at the DUT of few μm. The preliminary results of the measurements are presented.

  18. A control technique of oxygen contamination by Ga beam irradiation in InN MOMBE growth

    International Nuclear Information System (INIS)

    Isamoto, K.; Uesaka, Y.; Yamamoto, A.; Hashimoto, A.

    2006-01-01

    We have investigated about a control technique of oxygen contamination into the InN layers by simultaneous irradiation of Ga beam during RF-MOMBE growth using the combination of the TMIn and the RF-plasma nitrogen sources. Red shifts of the band gap energy and the improvement of the electrical properties have been achieved by the Ga beam irradiation. The suppression mechanism of the oxygen contamination has been discussed from the experimental results of the InN growth by the RF-MOMBE with the Ga beam irradiation. The present results strongly indicate that the simultaneous irradiation of the Ga beam would be useful to suppress the oxygen contamination into the InN layers during the growth. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Ga lithography in sputtered niobium for superconductive micro and nanowires

    International Nuclear Information System (INIS)

    Henry, M. David; Wolfley, Steve; Monson, Todd; Lewis, Rupert

    2014-01-01

    This work demonstrates the use of focused ion beam (FIB) implanted Ga as a lithographic mask for plasma etching of Nb films. Using a highly collimated Ga beam of a FIB, Nb is implanted 12 nm deep with a 14 nm thick Ga layer providing etch selectivity better than 15:1 with fluorine based etch chemistry. Implanted square test patterns, both 10 μm by 10 μm and 100 μm by 100 μm, demonstrate that doses above than 7.5 × 10 15  cm −2 at 30 kV provide adequate mask protection for a 205 nm thick, sputtered Nb film. The resolution of this dry lithographic technique is demonstrated by fabrication of nanowires 75 nm wide by 10 μm long connected to 50 μm wide contact pads. The residual resistance ratio of patterned Nb films was 3. The superconducting transition temperature (T c ) = 7.7 K was measured using a magnetic properties measurement system. This nanoscale, dry lithographic technique was extended to sputtered TiN and Ta here and could be used on other fluorine etched superconductors such as NbN, NbSi, and NbTi.

  20. An analytical simulation technique for cone-beam CT and pinhole SPECT

    International Nuclear Information System (INIS)

    Zhang Xuezhu; Qi Yujin

    2011-01-01

    This study was aimed at developing an efficient simulation technique with an ordinary PC. The work involved derivation of mathematical operators, analytic phantom generations, and effective analytical projectors developing for cone-beam CT and pinhole SPECT imaging. The computer simulations based on the analytical projectors were developed by ray-tracing method for cone-beam CT and voxel-driven method for pinhole SPECT of degrading blurring. The 3D Shepp-Logan, Jaszczak and Defrise phantoms were used for simulation evaluations and image reconstructions. The reconstructed phantom images were of good accuracy with the phantoms. The results showed that the analytical simulation technique is an efficient tool for studying cone-beam CT and pinhole SPECT imaging. (authors)

  1. Characterization of the Plasma Edge for Technique of Atomic Helium Beam in the CIEMAT Fusion Device

    International Nuclear Information System (INIS)

    Hidalgo, A.

    2003-01-01

    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 )

  2. Implementation of intra-cavity beam shaping technique to enhance pump efficiency

    CSIR Research Space (South Africa)

    Litvin, IA

    2012-02-01

    Full Text Available In this work the author proposes an implementation of a new intra-cavity beam shaping technique to vary the intensity distribution of the fundamental mode in a resonator cavity while maintaining a constant intensity distribution at the output...

  3. Ion beam texturing

    Science.gov (United States)

    Hudson, W. R.

    1977-01-01

    A microscopic surface texture was created by sputter-etching a surface while simultaneously sputter-depositing a lower sputter yield material onto the surface. A xenon ion-beam source was used to perform the texturing process on samples as large as 3-cm diameter. Textured surfaces have been characterized with SEM photomicrographs for a large number of materials including Cu, Al, Si, Ti, Ni, Fe, stainless steel, Au, and Ag. A number of texturing parameters are studied including the variation of texture with ion-beam powder, surface temperature, and the rate of texture growth with sputter etching time.

  4. Squids, snakes, and polarimeters: A new technique for measuring the magnetic moments of polarized beams

    International Nuclear Information System (INIS)

    Cameron, P.R.; Luccio, A.U.; Shea, T.J.; Tsoupas, N.; Goldberg, D.A.

    1997-01-01

    Effective polarimetry at high energies in hadron and lepton synchrotrons has been a long-standing and difficult problem. In synchrotrons with polarized beams it is possible to cause the direction of the polarization vector of a given bunch to alternate at a frequency which is some subharmonic of the rotation frequency. This can result in the presence of lines in the beam spectrum which are due only to the magnetic moment of the beam and which are well removed from the various lines due to the charge of the beam. The magnitude of these lines can be calculated from first principles. They are many orders of magnitude weaker than the Schottky signals. Measurement of the magnitude of one of these lines would be an absolute measurement of beam polarization. For measuring magnetic field, the Superconducting Quantum Interference Device, or squid, is about five orders of magnitude more sensitive than any other transducer. Using a squid, such a measurement might be accomplished with the proper combination of shielding, pickup loop design, and filtering. The resulting instrument would be fast, non-destructive, and comparatively cheap. In addition, techniques developed in the creation of such an instrument could be used to measure the Schottky spectrum in unprecedented detail. We present specifics of a polarimeter design for the Relativistic Heavy Ion Collider (RHIC) and briefly discuss the possibility of using this technique to measure polarization at high-energy electron machines like LEP and HERA. copyright 1997 American Institute of Physics

  5. 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.

  6. Solar system sputtering

    Science.gov (United States)

    Tombrello, T. A.

    1982-01-01

    The sites and materials involved in solar system sputtering of planetary surfaces are reviewed, together with existing models for the processes of sputtering. Attention is given to the interaction of the solar wind with planetary atmospheres in terms of the role played by the solar wind in affecting the He-4 budget in the Venus atmosphere, and the erosion and differentiation of the Mars atmosphere by solar wind sputtering. The study is extended to the production of isotopic fractionation and anomalies in interplanetary grains by irradiation, and to erosion effects on planetary satellites with frozen volatile surfaces, such as with Io, Europa, and Ganymede. Further measurements are recommended of the molecular form of the ejected material, the yields and energy spectra of the sputtered products, the iosotopic fractionation sputtering causes, and the possibility of electronic sputtering enhancement with materials such as silicates.

  7. RF photo-injector beam energy distribution studies by slicing technique

    Science.gov (United States)

    Filippetto, D.; Bellaveglia, M.; Musumeci, P.; Ronsivalle, C.

    2009-07-01

    The SPARC photo-injector is an R&D facility dedicated to the production of high brightness electron beams for radiation generation via FEL or Thomson scattering processes. It is the prototype injector for the recently approved SPARX project, aiming at the construction in the Frascati/University of Rome Tor Vergata area of a new high brightness electron linac for the generation of SASE-FEL radiation in the 1-10 nm wavelength range. The first phase of the SPARC project has been dedicated to the e-beam source characterization; the beam transverse and longitudinal parameters at the exit of the gun have been measured, and the photo-injector settings optimized to achieve best performance. Several beam dynamics topics have been experimentally studied in this first phase of operation, as, for example, the effect of photocathode driver laser beam shaping and the evolution of the beam transverse emittance. These studies have been made possible by the use of a novel diagnostic tool, the " emittance-meter" which enables the measurement of the transverse beam parameters at different positions along the propagation axis in the very interesting region at the exit of the RF gun. The new idea of extending the e-meter capabilities came out more recently. Information on the beam longitudinal phase space and correlations with the transverse planes can be retrieved by the slicing technique. In this paper, we illustrate the basic concept of the measurement together with simulations that theoretically validate the methodology. Some preliminary results are discussed and explained with the aid of code simulations.

  8. Introduction to analytical techniques of beam-target interactions and resolutions

    International Nuclear Information System (INIS)

    Ruste, J.

    1995-08-01

    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

  9. Neutron Spectroscopy for pulsed beams with frame overlap using a double time-of-flight technique

    Science.gov (United States)

    Harrig, K. P.; Goldblum, B. L.; Brown, J. A.; Bleuel, D. L.; Bernstein, L. A.; Bevins, J.; Harasty, M.; Laplace, T. A.; Matthews, E. F.

    2018-01-01

    A new double time-of-flight (dTOF) neutron spectroscopy technique has been developed for pulsed broad spectrum sources with a duty cycle that results in frame overlap, where fast neutrons from a given pulse overtake slower neutrons from previous pulses. Using a tunable beam at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory, neutrons were produced via thick-target breakup of 16 MeV deuterons on a beryllium target in the cyclotron vault. The breakup spectral shape was deduced from a dTOF measurement using an array of EJ-309 organic liquid scintillators. Simulation of the neutron detection efficiency of the scintillator array was performed using both GEANT4 and MCNP6. The efficiency-corrected spectral shape was normalized using a foil activation technique to obtain the energy-dependent flux of the neutron beam at zero degrees with respect to the incoming deuteron beam. The dTOF neutron spectrum was compared to spectra obtained using HEPROW and GRAVEL pulse height spectrum unfolding techniques. While the unfolding and dTOF results exhibit some discrepancies in shape, the integrated flux values agree within two standard deviations. This method obviates neutron time-of-flight spectroscopy challenges posed by pulsed beams with frame overlap and opens new opportunities for pulsed white neutron source facilities.

  10. A novel technique for tuning of co-axial cavity of multi-beam klystron

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Sukalyan, E-mail: sstechno18@gmail.com; Bandyopadhyay, Ayan Kumar; Pal, Debashis; Kant, Deepender; Joshi, Lalit Mohan; Kumar, Bijendra; Meena, Rakesh; Rawat, Vikram [Microwave Tubes Division, CSIR-CEERI, Pilani, Rajasthan-333031 (India)

    2016-03-09

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Iizuka, Kanji; Jung, JaeHun; Yokota, Hiroshi [Nippon Institute of Technology, 4-1 Gakuendai, Miyashiro, Minami-saitama, Saitama 3458501 (Japan)

    2014-05-15

    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.

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

    International Nuclear Information System (INIS)

    Iizuka, Kanji; Jung, JaeHun; Yokota, Hiroshi

    2014-01-01

    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

  13. Processing of La/sub 1.8/Sr/sub 0.2/CuO4 and YBa2Cu3O7 superconducting thin films by dual-ion-beam sputtering

    International Nuclear Information System (INIS)

    Madakson, P.; Cuomo, J.J.; Yee, D.S.; Roy, R.A.; Scilla, G.

    1988-01-01

    High quality La/sub 1.8/Sr/sub 0.2/CuO 4 and YBa 2 Cu 3 O 7 superconducting thin films, with zero resistance at 88 K, have been made by dual-ion-beam sputtering of metal and oxide targets at elevated temperatures. The films are about 1.0 μm thick and are single phase after annealing. The substrates investigated are Nd-YAP, MgO, SrF 2 , Si, CaF 2 , ZrO 2 -9% Y 2 O 3 , BaF 2 , Al 2 O 3 , and SrTiO 3 . Characterization of the films was carried out using Rutherford backscattering spectroscopy, resistivity measurements, transmission electron microscopy, x-ray diffraction, and secondary ion mass spectroscopy. Substrate/film interaction was observed in every case. This generally involves diffusion of the substrate into the film, which is accompanied by, for example, the replacement of Ba by Sr in the YBa 2 Cu 2 O 7 structure, in the case of SrTiO 3 substrate. The best substrates were those that did not significantly diffuse into the film and which did not react chemically with the film. In general, the superconducting transition temperature is found to depend on substrate temperature and ion beam energy, film composition, annealing conditions, and the nature and the magnitude of the substrate/film interaction

  14. Nuclear analytical techniques with neutron beams at the Univ. of Texas at Austin

    International Nuclear Information System (INIS)

    Uenlue, K.; Wehring, B.W.

    1996-01-01

    Neutron beams produced by nuclear research reactors can be used for analytical chemical analysis by measuring nuclear radiation produced by neutron capture. Prompt gamma activation analysis (PGAA) and neutron depth profiling (NDP) are two such analytical techniques. For the last three decades, these techniques have been applied at a number of research reactors around the world. Within the last 4 yr, we have developed NDP and PGAA facilities at The University of Texas at Austin research reactor, a 1-MW TRIGA Mark II reactor. Brief descriptions of the facilities and summaries of activities for these analytical techniques at the University of Texas at Austin are provided in this paper

  15. An experiment on the dynamics of ion implantation and sputtering of surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Wright, G. M.; Barnard, H. A.; Kesler, L. A.; Peterson, E. E.; Stahle, P. W.; Sullivan, R. M.; Whyte, D. G.; Woller, K. B. [Plasma Science and Fusion Center, MIT, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

    2014-02-15

    A major impediment towards a better understanding of the complex plasma-surface interaction is the limited diagnostic access to the material surface while it is undergoing plasma exposure. The Dynamics of ION Implantation and Sputtering Of Surfaces (DIONISOS) experiment overcomes this limitation by uniquely combining powerful, non-perturbing ion beam analysis techniques with a steady-state helicon plasma exposure chamber, allowing for real-time, depth-resolved in situ measurements of material compositions during plasma exposure. Design solutions are described that provide compatibility between the ion beam analysis requirements in the presence of a high-intensity helicon plasma. The three primary ion beam analysis techniques, Rutherford backscattering spectroscopy, elastic recoil detection, and nuclear reaction analysis, are successfully implemented on targets during plasma exposure in DIONISOS. These techniques measure parameters of interest for plasma-material interactions such as erosion/deposition rates of materials and the concentration of plasma fuel species in the material surface.

  16. An experiment on the dynamics of ion implantation and sputtering of surfaces

    International Nuclear Information System (INIS)

    Wright, G. M.; Barnard, H. A.; Kesler, L. A.; Peterson, E. E.; Stahle, P. W.; Sullivan, R. M.; Whyte, D. G.; Woller, K. B.

    2014-01-01

    A major impediment towards a better understanding of the complex plasma-surface interaction is the limited diagnostic access to the material surface while it is undergoing plasma exposure. The Dynamics of ION Implantation and Sputtering Of Surfaces (DIONISOS) experiment overcomes this limitation by uniquely combining powerful, non-perturbing ion beam analysis techniques with a steady-state helicon plasma exposure chamber, allowing for real-time, depth-resolved in situ measurements of material compositions during plasma exposure. Design solutions are described that provide compatibility between the ion beam analysis requirements in the presence of a high-intensity helicon plasma. The three primary ion beam analysis techniques, Rutherford backscattering spectroscopy, elastic recoil detection, and nuclear reaction analysis, are successfully implemented on targets during plasma exposure in DIONISOS. These techniques measure parameters of interest for plasma-material interactions such as erosion/deposition rates of materials and the concentration of plasma fuel species in the material surface

  17. Beam profile measurements on the advanced test accelerator using optical techniques

    International Nuclear Information System (INIS)

    Chong, Y.P.; Kalibjian, R.; Cornish, J.P.; Kallman, J.S.; Donnelly, D.

    1986-01-01

    Beam current density profiles of ATA have been measured both spatially and temporally using a number of diagnostics. An extremely important technique involves measuring optical emissions from either a target foil inserted into the beam path or gas atoms and molecules excited by beam electrons. This paper describes the detection of the optical emission. A 2-D gated television camera with a single or dual micro-channel-plate (MCP) detector for high gain provides excellent spatial and temporal resolution. Measurements are routinely made with resolutions of 1 mm and 5 ns respectively. The optical line of sight allows splitting part of the signal to a streak camera or photometer for even higher time resolution

  18. Characterization of beam dynamics in the APS injector rings using time-resolved imaging techniques

    International Nuclear Information System (INIS)

    Yang, B.X.; Lumpkin, A.H.; Borland, M.

    1997-01-01

    Images taken with streak cameras and gated intensified cameras with both time (longitudinal) and spatial (transverse) resolution reveal a wealth of information about circular accelerators. The authors illustrate a novel technique by a sequence of dual-sweep streak camera images taken at a high dispersion location in the booster synchrotron, where the horizontal coordinate is strongly correlated with the particle energy and the open-quotes top-viewclose quotes of the beam gives a good approximation to the particle density distribution in the longitudinal phase space. A sequence of top-view images taken fight after injection clearly shows the beam dynamics in the phase space. We report another example from the positron accumulator ring for the characterization of its beam compression bunching with the 12th harmonic rf

  19. Estimating the vibration level of an L-shaped beam using power flow techniques

    Science.gov (United States)

    Cuschieri, J. M.; Mccollum, M.; Rassineux, J. L.; Gilbert, T.

    1986-01-01

    The response of one component of an L-shaped beam, with point force excitation on the other component, is estimated using the power flow method. The transmitted power from the source component to the receiver component is expressed in terms of the transfer and input mobilities at the excitation point and the joint. The response is estimated both in narrow frequency bands, using the exact geometry of the beams, and as a frequency averaged response using infinite beam models. The results using this power flow technique are compared to the results obtained using finite element analysis (FEA) of the L-shaped beam for the low frequency response and to results obtained using statistical energy analysis (SEA) for the high frequencies. The agreement between the FEA results and the power flow method results at low frequencies is very good. SEA results are in terms of frequency averaged levels and these are in perfect agreement with the results obtained using the infinite beam models in the power flow method. The narrow frequency band results from the power flow method also converge to the SEA results at high frequencies. The advantage of the power flow method is that detail of the response can be retained while reducing computation time, which will allow the narrow frequency band analysis of the response to be extended to higher frequencies.

  20. TOF technique for laser-driven proton beam diagnostics for the ELIMED beamline

    International Nuclear Information System (INIS)

    Milluzzo, G.; Scuderi, V.; Amico, A.G.; Cirrone, G.A.P.; Cuttone, G.; Larosa, G.; Leanza, R.; Petringa, G.; Pipek, J.; Romano, F.; Napoli, M. De; Dostal, J.; Margarone, D.; Schillaci, F.; Velyhan, A.

    2017-01-01

    The Time of Flight (TOF) method for laser-driven ion beam diagnostics has been extensively investigated so far for low energy ion diagnostics and several works, reported in literature [1,2], have shown its efficiency in the measurement of particle beam characteristics such as ion species, energy spectrum and current. Moreover, such technique allows obtaining a shot-to-shot on-line monitoring of optically accelerated particles, necessary to control the reproducibility of the accelerated beam and to deliver a beam suitable for any kind of applications. For this reason, the ELIMED beamline [3,4], which will be entirely developed at INFN-LNS and installed in 2017 within the ion beamline ELIMAIA (ELI Multidisciplinary Applications of laser-Ion Acceleration) experimental hall at ELI-Beamlines in Prague, will be equipped with an on-line diagnostics system composed by silicon carbide and diamond detectors, using the TOF technique. In this contribution, the procedure developed for TOF signal analysis will be briefly reported.

  1. Minimal interference beam size/profile measurement techniques applicable to the Collider

    International Nuclear Information System (INIS)

    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

  2. Characterization of Niobium Oxide Films Deposited by High Target Utilization Sputter Sources

    International Nuclear Information System (INIS)

    Chow, R; Ellis, A D; Loomis, G E; Rana, S I

    2007-01-01

    High quality, refractory metal, oxide coatings are required in a variety of applications such as laser optics, micro-electronic insulating layers, nano-device structures, electro-optic multilayers, sensors and corrosion barriers. A common oxide deposition technique is reactive sputtering because the kinetic mechanism vaporizes almost any solid material in vacuum. Also, the sputtered molecules have higher energies than those generated from thermal evaporation, and so the condensates are smoother and denser than those from thermally-evaporated films. In the typical sputtering system, target erosion is a factor that drives machine availability. In some situations such as nano-layered capacitors, where the device's performance characteristics depends on thick layers, target life becomes a limiting factor on the maximizing device functionality. The keen interest to increase target utilization in sputtering has been addressed in a variety of ways such as target geometry, rotating magnets, and/or shaped magnet arrays. Also, a recent sputtering system has been developed that generates a high density plasma, directs the plasma beam towards the target in a uniform fashion, and erodes the target in a uniform fashion. The purpose of this paper is to characterize and compare niobia films deposited by two types of high target utilization sputtering sources, a rotating magnetron and a high density plasma source. The oxide of interest in this study is niobia because of its high refractive index. The quality of the niobia films were characterized spectroscopically in optical transmission, ellipsometrically, and chemical stoichiometry with X-ray photo-electron spectroscopy. The refractive index, extinction coefficients, Cauchy constants were derived from the ellipsometric modeling. The mechanical properties of coating density and stress are also determined

  3. Sputtering induced surface composition changes in copper-palladium alloys

    International Nuclear Information System (INIS)

    Sundararaman, M.; Sharma, S.K.; Kumar, L.; Krishnan, R.

    1981-01-01

    It has been observed that, in general, surface composition is different from bulk composition in multicomponent materials as a result of ion beam sputtering. This compositional difference arises from factors like preferential sputtering, radiation induced concentration gradients and the knock-in effect. In the present work, changes in the surface composition of copper-palladium alloys, brought about by argon ion sputtering, have been studied using Auger electron spectroscopy. Argon ion energy has been varied from 500 eV to 5 keV. Enrichment of palladium has been observed in the sputter-altered layer. The palladium enrichment at the surface has been found to be higher for 500 eV argon ion sputtering compared with argon ion sputtering at higher energies. Above 500 eV, the surface composition has been observed to remain the same irrespective of the sputter ion energy for each alloy composition. The bulk composition ratio of palladium to copper has been found to be linearly related to the sputter altered surface composition ratio of palladium to copper. These results are discussed on the basis of recent theories of alloy sputtering. (orig.)

  4. The analysis of composite laminated beams using a 2D interpolating meshless technique

    Science.gov (United States)

    Sadek, S. H. M.; Belinha, J.; Parente, M. P. L.; Natal Jorge, R. M.; de Sá, J. M. A. César; Ferreira, A. J. M.

    2018-02-01

    Laminated composite materials are widely implemented in several engineering constructions. For its relative light weight, these materials are suitable for aerospace, military, marine, and automotive structural applications. To obtain safe and economical structures, the modelling analysis accuracy is highly relevant. Since meshless methods in the recent years achieved a remarkable progress in computational mechanics, the present work uses one of the most flexible and stable interpolation meshless technique available in the literature—the Radial Point Interpolation Method (RPIM). Here, a 2D approach is considered to numerically analyse composite laminated beams. Both the meshless formulation and the equilibrium equations ruling the studied physical phenomenon are presented with detail. Several benchmark beam examples are studied and the results are compared with exact solutions available in the literature and the results obtained from a commercial finite element software. The results show the efficiency and accuracy of the proposed numeric technique.

  5. The kick-out mass selection technique for ions stored in an Electrostatic Ion Beam Trap

    International Nuclear Information System (INIS)

    Toker, Y; Altstein, N; Aviv, O; Rappaport, M L; Heber, O; Schwalm, D; Strasser, D; Zajfman, D

    2009-01-01

    A simple mass selection technique which allows one to clean a keV ion beam of undesirable masses while stored in an Electrostatic Ion Beam Trap (EIBT) is described. The technique is based on the time-of-flight principle and takes advantage of the long storage times and self-bunching that are possible in this type of traps (self bunching being the effect that keeps ions of the same mass bunched in spite of their finite distributions of velocities and trajectories). As the oscillation period is proportional to the square root of the ion mass, bunches containing ions of different masses will separate in space with increasing storage time and can be kicked out by a pulsed deflector mounted inside the trap. A mass selector of this type has been implemented successfully in an EIBT connected to an Even-Lavie supersonic expansion source and is routinely used in ongoing cluster experiments.

  6. Sputtering of water ice

    DEFF Research Database (Denmark)

    Baragiola, R.A.; Vidal, R.A.; Svendsen, W.

    2003-01-01

    We present results of a range of experiments of sputtering of water ice together with a guide to the literature. We studied how sputtering depends on the projectile energy and fluence, ice growth temperature, irradiation temperature and external electric fields. We observed luminescence from...

  7. Active Vibration damping of Smart composite beams based on system identification technique

    Science.gov (United States)

    Bendine, Kouider; Satla, Zouaoui; Boukhoulda, Farouk Benallel; Nouari, Mohammed

    2018-03-01

    In the present paper, the active vibration control of a composite beam using piezoelectric actuator is investigated. The space state equation is determined using system identification technique based on the structure input output response provided by ANSYS APDL finite element package. The Linear Quadratic (LQG) control law is designed and integrated into ANSYS APDL to perform closed loop simulations. Numerical examples for different types of excitation loads are presented to test the efficiency and the accuracy of the proposed model.

  8. 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....

  9. Compositional analysis of YBaCuO superconducting films with ion beam analysis techniques

    International Nuclear Information System (INIS)

    Jones, S.; Timmers, H.; Ophel, T.R.; Elliman, R.G.

    1999-01-01

    High-T c YBa x Cu y O 7-δ superconducting films are being developed for applications such as superconducting quantum interference devices. The carrier concentration, critical current density J c and critical temperature T c of these films depend sensitively on the oxygen content . Stoichiometry, uniformity with depth, homogeneity across the sample and film thickness are also important quantities for their characterisation. It has been shown, for example, that the stoichiometry of the metallic elements affects the growth characteristics and surface morphology of the films. With the deposit ion techniques used, reproducibility of film properties is difficult. The characterisation of YBa x Cu y O 7-δ films with ion beam analysis techniques is complex. Whereas the three metallic elements can be detected with helium beams and Rutherford Backscattering (RBS), the oxygen signal is generally obscured by that from substrate elements. It can be better detected using resonant backscattering with 3.04MeV 4 He ions or nuclear reaction analysis. Elastic Recoil Detection (ERD) with high-energetic (1MeV/amu), heavy beams (Z > 120), enables all elements to be detected and separated in a single experiment. It is well established that ion bombardment induces vacancies in the oxygen sub-lattice, driving the material to change from crystalline to amorphous, the latter phase having a reduced oxygen content. In previous heavy ion ERD measurements of YBa x Cu yO z films with 200MeV 127 I beams, the opaque films became transparent in the beam spot area, indicative of the amorphous phase. The accuracy of the oxygen measurement is therefore questionable. Indeed, using Raman spectroscopy, distortions of the crystalline structure above a fluence of 5 x 10 11 ion/cm 2 and for higher doses some signatures of a reduction in oxygen content have been observed for such beams. It appears therefore that a correct determination of the oxygen content requires either a drastic reduction in fluence or a

  10. Dwell time dependent morphological transition and sputtering yield of ion sputtered Sn

    International Nuclear Information System (INIS)

    Qian, H X; Zeng, X R; Zhou, W

    2010-01-01

    Self-organized nano-scale patterns may appear on a wide variety of materials irradiated with an ion beam. Good manipulation of these structures is important for application in nanostructure fabrication. In this paper, dwell time has been demonstrated to be able to control the ripple formation and sputtering yield on Sn surface. Ripples with a wavelength of 1.7 μm were observed for a dwell time in the range 3-20 μs, whereas much finer ripples with a wavelength of 540 nm and a different orientation were observed for a shorter dwell time in the range 0.1-2 μs. The sputtering yield increases with dwell time significantly. The results provide a new basis for further steps in the theoretical description of morphology evolution during ion beam sputtering.

  11. Nanosecond and femtosecond mass spectroscopic analysis of a molecular beam produced by the spray-jet technique

    International Nuclear Information System (INIS)

    Yamada, Toshiki; Shinohara, Hidenori; Kamikado, Toshiya; Okuno, Yoshishige; Suzuki, Hitoshi; Mashiko, Shinro; Yokoyama, Shiyoshi

    2008-01-01

    The spray-jet molecular beam apparatus enabled us to produce a molecular beam of non-volatile molecules under high vacuum from a sprayed mist of sample solutions. The apparatus has been used in spectroscopic studies and as a means of molecular beam deposition. We analyzed the molecular beam, consisting of non-volatile, solvent, and carrier-gas molecules, by using femtosecond- and nanosecond- laser mass spectroscopy. The information thus obtained provided insight into the molecular beam produced by the spray-jet technique

  12. 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].

  13. A novel calorimetry technique for monitoring electron beam curing of polymer resins

    International Nuclear Information System (INIS)

    Chen, J.H.; Johnston, A.; Petrescue, L.; Hojjati, M.

    2006-01-01

    This paper describes the development of a calorimetry-based technique for monitoring of the curing of electron beam (EB) curable resins, including design of the calorimeter hardware and the development of an analytical model for calculating resin cure rates and radiation dose. Factors affecting the performance of the calorimeter were investigated. Experimental trials monitoring the curing of epoxy resin were conducted under single pass and multiple passes of EB irradiation. Results show that the developed calorimeter is a simple, inexpensive and reasonably accurate technique for monitoring the EB curing of cationic epoxies

  14. Topography induced by sputtering in a magnetic sector instrument: an AFM and SEM study

    International Nuclear Information System (INIS)

    Iacob, E.; Bersani, M.; Lui, A.; Giubertoni, D.; Barozzi, M.; Anderle, M.

    2004-01-01

    Due to the sensitivity, the good depth resolution and the great interest in ultra shallow profile, secondary ion mass spectrometry (SIMS) is one of the prime techniques used in the semiconductor industry. Low impact energy beams are required to profile shallow distributions. Since Cs + beam sputtering can cause morphological artifacts as well as O 2 + beam does, a detailed study is required to understand development and limiting analytical conditions. In this work we analyzed the effect of low energy Cs + primary beam incident at 68 deg. and 78 deg. on different silicon samples. By using atomic force microscopy (AFM) and scanning electron microscopy (SEM) we underline their reliability and correlate the morphological effects to the SIMS analytical parameters and samples characteristics

  15. Reducing beam shaper alignment complexity: diagnostic techniques for alignment and tuning

    Science.gov (United States)

    Lizotte, Todd E.

    2011-10-01

    Safe and efficient optical alignment is a critical requirement for industrial laser systems used in a high volume manufacturing environment. Of specific interest is the development of techniques to align beam shaping optics within a beam line; having the ability to instantly verify by a qualitative means that each element is in its proper position as the beam shaper module is being aligned. There is a need to reduce these types of alignment techniques down to a level where even a newbie to optical alignment will be able to complete the task. Couple this alignment need with the fact that most laser system manufacturers ship their products worldwide and the introduction of a new set of variables including cultural and language barriers, makes this a top priority for manufacturers. Tools and methodologies for alignment of complex optical systems need to be able to cross these barriers to ensure the highest degree of up time and reduce the cost of maintenance on the production floor. Customers worldwide, who purchase production laser equipment, understand that the majority of costs to a manufacturing facility is spent on system maintenance and is typically the largest single controllable expenditure in a production plant. This desire to reduce costs is driving the trend these days towards predictive and proactive, not reactive maintenance of laser based optical beam delivery systems [10]. With proper diagnostic tools, laser system developers can develop proactive approaches to reduce system down time, safe guard operational performance and reduce premature or catastrophic optics failures. Obviously analytical data will provide quantifiable performance standards which are more precise than qualitative standards, but each have a role in determining overall optical system performance [10]. This paper will discuss the use of film and fluorescent mirror devices as diagnostic tools for beam shaper module alignment off line or in-situ. The paper will also provide an overview

  16. 14th International Workshop on Slow Positron Beam Techniques and Applications

    International Nuclear Information System (INIS)

    2017-01-01

    These proceedings arose from the 14th International Workshop on Slow Positron Beam Techniques (SLOPOS14), which was held at Kunibiki Messe, Matsue, Shimane prefecture, Japan, from the 22nd—27th May 2016. Meetings in the SLOPOS series are held every three years. The SLOPOS workshop series has traditionally been devoted to investigations on the production of positron and positronium beams, their fundamental physics and chemistry, and their applications to materials such as metals, semiconductors and soft matter. During the workshop numerous applications using positron and positronium beams were also presented, clearly demonstrating the usefulness of such beams to the determination of surface structure, defect characterization as well as to fundamental scientific studies. For SLOPOS14 the main subjects of the workshop included the following: • Positron transport and beam technology • Pulsed positron beams and positron traps • Defect profiling in bulk and layered structures • Nano structures, porous materials and thin films • Surface and interface analysis • Positronium formation, emission and beams • Positron and positronium interactions with atoms and molecules • Many positrons and anti-hydrogen • Improvement of experimental techniques 106 delegates from 14 countries participated in the SLOPOS14, including 31 student delegates, which was a most encouraging sign for the future. The scientific program comprised 5 plenary talks, 22 invited talks, 32 contributed talks and 46 posters presented during two poster sessions. Student prizes were awarded for the best presented scientific contributions by 4 students from University of College London, Universität der Bundeswehr München and The University of Tokyo. On a sad note, delegates paid tribute to the contributions of our recently deceased colleagues, Prof. A. Seeger, Prof. R.N. West, Prof. T.C. Griffith, and Prof. Z. Tang. Memorial talks were given and a one minute silence was observed before the

  17. Secondary growth mechanism of SiGe islands deposited on a mixed-phase microcrystalline Si by ion beam co-sputtering.

    Science.gov (United States)

    Ke, S Y; Yang, J; Qiu, F; Wang, Z Q; Wang, C; Yang, Y

    2015-11-06

    We discuss the SiGe island co-sputtering deposition on a microcrystalline silicon (μc-Si) buffer layer and the secondary island growth based on this pre-SiGe island layer. The growth phenomenon of SiGe islands on crystalline silicon (c-Si) is also investigated for comparison. The pre-SiGe layer grown on μc-Si exhibits a mixed-phase structure, including SiGe islands and amorphous SiGe (a-SiGe) alloy, while the layer deposited on c-Si shows a single-phase island structure. The preferential growth and Ostwald ripening growth are shown to be the secondary growth mechanism of SiGe islands on μc-Si and c-Si, respectively. This difference may result from the effect of amorphous phase Si (AP-Si) in μc-Si on the island growth. In addition, the Si-Ge intermixing behavior of the secondary-grown islands on μc-Si is interpreted by constructing the model of lateral atomic migration, while this behavior on c-Si is ascribed to traditional uphill atomic diffusion. It is found that the aspect ratios of the preferential-grown super islands are higher than those of the Ostwald-ripening ones. The lower lateral growth rate of super islands due to the lower surface energy of AP-Si on the μc-Si buffer layer for the non-wetting of Ge at 700 °C and the stronger Si-Ge intermixing effect at 730 °C may be responsible for this aspect ratio difference.

  18. Influence of surface topography on the sputtering yields of silver

    International Nuclear Information System (INIS)

    Pan Jisheng; Wang Zhenxia; Tao Zhenlan; Zhang Jiping

    1992-01-01

    The sputtering yields of silver have been measured as a function of the fluence of incident Ar + ions (27 keV) using the collector technique and RBS analysis. The irradiated surface was examined by scanning electron microscopy (SEM). It is shown that the sputtering yields of surfaces with topography are enhanced relative to smooth surfaces of silver, but the extent of the enhancement depends on the irradiation dose. The experimental results can be explained assuming that the surface topography and sputtering yield are a function of incident angle. It is obvious that the surface topography is an important factor to influence the sputtering yield. The term ''apparent sputtering yield'' has specifically been used when referring to the experimental sputtering yield of a surface with topography, to emphasize the difference with a smooth surface. (orig.)

  19. Techniques for preparing isotopic targets

    International Nuclear Information System (INIS)

    Xu Guoji; Guan Shouren; Luo Xinghua; Sun Shuhua

    1987-12-01

    The techniques of making isotopic targets for nuclear physics experiments are introduced. Vacuum evaporation, electroplating, centrifugal precipitation, rolling and focused heavy-ion beam sputtering used to prepare various isotopic targets at IAE are described. Reduction-distillation with active metals and electrolytic reduction for converting isotope oxides to metals are mentioned. The stripping processes of producing self-supporting isotopic targets are summarized. The store methods of metallic targets are given

  20. Low temperature perovskite crystallization of highly tunable dielectric Ba0.7Sr0.3TiO3 thick films deposited by ion beam sputtering on platinized silicon substrates

    Science.gov (United States)

    Zhu, X. H.; Guigues, B.; Defaÿ, E.; Dubarry, C.; Aïd, M.

    2009-02-01

    Ba0.7Sr0.3TiO3 (BST) thick films with thickness up to 1 μm were deposited on Pt-coated silicon substrates by ion beam sputtering, followed by an annealing treatment. It is demonstrated that pure well-crystallized perovskite phase could be obtained in thick BST films by a low temperature process (535 °C). The BST thick films show highly tunable dielectric properties with tunability (at 800 kV/cm) up to 51.0% and 66.2%, respectively, for the 0.5 and 1 μm thick films. The relationship between strains and dielectric properties was systematically investigated in the thick films. The results suggest that a comparatively larger tensile thermal in-plane strain (0.15%) leads to the degradation in dielectric properties of the 0.5 μm thick film; besides, strong defect-related inhomogeneous strains (˜0.3%) make the dielectric peaks smearing and broadening in the thick films, which, however, preferably results in high figure-of-merit factors over a wide operating temperature range. Moreover, the leakage current behavior in the BST thick films was found to be dominated by the space-charge-limited-current mechanism, irrespective of the film thickness.

  1. Processing of La(1.8)Sr(0.2)CuO4 and YBa2Cu3O7 superconducting thin films by dual-ion-beam sputtering

    Science.gov (United States)

    Madakson, P.; Cuomo, J. J.; Yee, D. S.; Roy, R. A.; Scilla, G.

    1988-03-01

    High-quality La(1.8)Sr(0.2)CuO4 and YBa2Cu3O7 superconducting thin films, with zero resistance at 88 K, have been made by dual-ion-beam sputtering of metal and oxide targets at elevated temperatures. The films are about 1.0 micron thick and are single phase after annealing. The substrates investigated are Nd-YAP, MgO, SrF2, Si, CaF2, ZrO2-(9 pct)Y2O3, BaF2, Al2O3, and SrTiO3. Characterization of the films was carried out using Rutherford backscattering spectroscopy, resistivity measurements, TEM, X-ray diffraction, and SIMS. Substrate/film interaction was observed in every case. This generally involves diffusion of the substrate into the film, which is accompanied by, for example, the replacement of Ba by Sr in the YBa2Cu2O7 structure, in the case of SrTiO3 substrate. The best substrates were those that did not significantly diffuse into the film and which did not react chemically with the film.

  2. Low temperature perovskite crystallization of highly tunable dielectric Ba0.7Sr0.3TiO3 thick films deposited by ion beam sputtering on platinized silicon substrates

    International Nuclear Information System (INIS)

    Zhu, X. H.; Defaye, E.; Aied, M.; Guigues, B.; Dubarry, C.

    2009-01-01

    Ba 0.7 Sr 0.3 TiO 3 (BST) thick films with thickness up to 1 μm were deposited on Pt-coated silicon substrates by ion beam sputtering, followed by an annealing treatment. It is demonstrated that pure well-crystallized perovskite phase could be obtained in thick BST films by a low temperature process (535 deg. C). The BST thick films show highly tunable dielectric properties with tunability (at 800 kV/cm) up to 51.0% and 66.2%, respectively, for the 0.5 and 1 μm thick films. The relationship between strains and dielectric properties was systematically investigated in the thick films. The results suggest that a comparatively larger tensile thermal in-plane strain (0.15%) leads to the degradation in dielectric properties of the 0.5 μm thick film; besides, strong defect-related inhomogeneous strains (∼0.3%) make the dielectric peaks smearing and broadening in the thick films, which, however, preferably results in high figure-of-merit factors over a wide operating temperature range. Moreover, the leakage current behavior in the BST thick films was found to be dominated by the space-charge-limited-current mechanism, irrespective of the film thickness

  3. (Ba+Sr)/Ti ratio dependence of the dielectric properties for (Ba0.5Sr0.5)TiO3 thin films prepared by ion beam sputtering

    Science.gov (United States)

    Yamamichi, Shintaro; Yabuta, Hisato; Sakuma, Toshiyuki; Miyasaka, Yoichi

    1994-03-01

    (Ba0.5Sr0.5)TiO3 thin films were prepared by ion beam sputtering from powder targets with (Ba+Sr)/Ti ratios ranging from 0.80 to 1.50. All of the perovskite (Ba,Sr)TiO3 films were single phase except for the film with a (Ba+Sr)/Ti ratio of 1.41. The dielectric constant values notably depended on the (Ba+Sr)/Ti ratio for films thicker than 70 nm. The highest dielectric constant of 580 was achieved for the 5% (Ba+Sr) rich film. This (Ba+Sr)/Ti ratio dependence was diminished by the thickness dependence for thinner films. The grain sizes for the 9% (Ba+Sr) rich film and for the 6% (Ba+Sr) poor film ranged from 70 to 100 nm and from 30 to 60 nm, respectively. This grain size difference could explain why slightly A-site rich (Ba,Sr)TiO3 films have a larger dielectric constant than A-site poor films.

  4. A dynamic plasmonic manipulation technique assisted by phase modulation of an incident optical vortex beam

    International Nuclear Information System (INIS)

    Yuan, G H; Wang, Q; Tan, P S; Lin, J; Yuan, X-C

    2012-01-01

    A novel phase modulation method for dynamic manipulation of surface plasmon polaritons (SPPs) with a phase engineered optical vortex (OV) beam illuminating on nanoslits is experimentally demonstrated. Because of the unique helical phase carried by an OV beam, dynamic control of SPP multiple focusing and standing wave generation is realized by changing the OV beam’s topological charge constituent with the help of a liquid-crystal spatial light modulator. Measurement of SPP distributions with near-field scanning optical microscopy showed an excellent agreement with numerical predictions. The proposed phase modulation technique for manipulating SPPs features has seemingly dynamic and reconfigurable advantages, with profound potential for development of SPP coupling, routing, multiplexing and high-resolution imaging devices on plasmonic chips. (paper)

  5. Studies on post weld heat treatment of dissimilar aluminum alloys by laser beam welding technique

    Science.gov (United States)

    Srinivas, B.; Krishna, N. Murali; Cheepu, Muralimohan; Sivaprasad, K.; Muthupandi, V.

    2018-03-01

    The present study mainly focuses on post weld heat treatment (PWHT) of AA5083 and AA6061 alloys by joining these using laser beam welding at three different laser power and two different beam spot sizes and three different welding speeds. Effects of these parameters on microstructural and mechanical properties like hardness, tensile strength were studied at PWHT condition and significant changes had been observed. The PWHT used was artificial aging technique. The microstructural observations revealed that there was a appreciable changes were taken place in the grain size. The microhardness observations proven that the change in the hardness profile in AA6061 was appreciable than in the AA5083. The tensile strength of 246 MPa was recorded as highest. The fractured surfaces observed are predominantly ductile in nature.

  6. Application of object oriented techniques in the TRIUMF beam line 2C control system

    International Nuclear Information System (INIS)

    Wilkinson, N.A.; Ludgate, G.A.

    1992-07-01

    The KAON Factory central control system study employed a uniform approach to requirements analysis, architectural design and programming based on well established object oriented principles. These principles were applied to the successful analysis, design and implementation of the control system for the TRIUMF Beam Line 2C Solid Target Facility. The specification for this control system was created in collaboration with Beam Line 2C equipment management experts and, once the analysis models were validated, an approach was developed for the direct translation of these models into C code. A commercial real time database was central to this translation, as inter-object data and control flows are implemented by channels in the database. This paper focuses on the experience gained in the use of object oriented techniques during the complete analysis-design-implementation cycle of a working control system and on the utility of implementing such a system using a commercial real time database and graphical interface. (author)

  7. The comparison of Co-60 and 4MV photons matching dosimetry during half-beam technique

    International Nuclear Information System (INIS)

    Cakir, Aydin; Bilge, Hatice; Dadasbilge, Alpar; Kuecuecuek, Halil; Okutan, Murat; Merdan Fayda, Emre

    2005-01-01

    In this phantom study, we tried to compare matching dosimetry differences between half-blocking of Co-60 and asymmetric collimation of the 4MV photons during craniospinal irradiation. The dose distributions are compared and discussed. Firstly, some gaps with different sizes are left between cranial and spinal field borders. Secondly, the fields are overlapped in the same sizes. We irradiate the films located in water-equivalent solid phantoms with Co-60 and 4MV photon beams. This study indicates that the field placement errors in +/- 1mm are acceptable for both Co-60 and 4MV photon energies during craniospinal irradiation with half-beam block technique. Within these limits the dose variations are specified in +/- 5%. However, the setup errors that are more than 1mm are unacceptable for both asymmetric collimation of 4MV photon and half-blocking of Co-60

  8. A new analysis technique to measure fusion excitation functions with large beam energy dispersions

    Science.gov (United States)

    Figuera, P.; Di Pietro, A.; Fisichella, M.; Lattuada, M.; Shotter, A. C.; Ruiz, C.; Zadro, M.

    2018-01-01

    Peculiar nuclear structures of two colliding nuclei such has clustering, neutron halo/skin or very low breakup thresholds can affect the reaction dynamics below the Coulomb barrier and this may also have astrophysical consequences. In order to have a better understanding of this topic, in the last decade, several experiments were performed. A typical experimental challenge of such studies is the need to measure excitation functions below the Coulomb barrier, having a strong energy dependence, with rather large beam energy dispersions inside the target. This may easily lead to ambiguities in associating the measured cross section with a proper beam energy. In this paper a discussion on this topic is reported and a new technique to deal with the above problem will be proposed.

  9. Gas Source Techniques for Molecular Beam Epitaxy of Highly Mismatched Ge Alloys

    Directory of Open Access Journals (Sweden)

    Chad A. Stephenson

    2016-12-01

    Full Text Available Ge and its alloys are attractive candidates for a laser compatible with silicon integrated circuits. Dilute germanium carbide (Ge1−xCx offers a particularly interesting prospect. By using a precursor gas with a Ge4C core, C can be preferentially incorporated in substitutional sites, suppressing interstitial and C cluster defects. We present a method of reproducible and upscalable gas synthesis of tetrakis(germylmethane, or (H3Ge4C, followed by the design of a hybrid gas/solid-source molecular beam epitaxy system and subsequent growth of defect-free Ge1−xCx by molecular beam epitaxy (MBE. Secondary ion mass spectroscopy, transmission electron microscopy and contactless electroreflectance confirm the presence of carbon with very high crystal quality resulting in a decrease in the direct bandgap energy. This technique has broad applicability to growth of highly mismatched alloys by MBE.

  10. Evaluation of Temporal Diagnostic Techniques for Two-Bunch Facet Beam

    Energy Technology Data Exchange (ETDEWEB)

    Litos, M.D.; Bionta, M.R.; Dolgashev, V.A.; England, R.J.; Fritz, D.; Gilevich, S.; Hering, Ph.; Hogan, M.J.; /SLAC

    2011-08-19

    Three temporal diagnostic techniques are considered for use in the FACET facility at SLAC, which will incorporate a unique two-bunch beam for plasma wakefield acceleration experiments. The results of these experiments will depend strongly on the the inter-bunch spacing as well as the longitudinal profiles of the two bunches. A reliable, singleshot, high resolution measurement of the beam's temporal profile is necessary to fully quantify the physical mechanisms underlying the beam driven plasma wakefield acceleration. In this study we show that a transverse deflecting cavity is the diagnostic which best meets our criteria. Based on our laboratory testing, numerical calculations, and simulations of the three single-shot temporal diagnostic devices, the X-band TCAV system is the best candidate for resolving FACET's two-bunch beam, with an estimated resolution of 7 {micro}m. Both the S-band TCAV system and the EO system could resolve the peak-to-peak separation of the two bunches in the FACET beam with estimated resolutions of 25 {micro}m and 30 {micro}m, respectively, but would be unable to resolve the temporal profiles of the individual bunches themselves. Because the TCAV signal is more easily interpreted and because the reliability of the EO system is less well known, however, the S-band TCAV system would be the next preferred option after the X-band TCAV system. The Fesca-200 streak camera, though simple, compact, and reliable, is unable to achieve a resolution that would be of use to FACET.

  11. Development of Plant Mutation Breeding Techniques and Mutants Using by Ion Beam

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Si Yong; Song, Hi Sup; Park, In Sook; Kim, Dong Sub; Lee, Hye Jeong

    2005-06-15

    In recent, Japanese scientists have revealed that high liner energy transfer (LET) heavy-ion beams have relative high biological effectiveness (RBE) and seem to be more effective for induced plant mutation than low LET radiation i.e., X-rays, gamma rays and electrons. This study was conducted to develop basic induced mutation techniques of ion-beam using the MC-50 cyclotron (50MeV) at the Korea Institute of Radiological and Medical Science. For the irradiation of ion-beam, not only dry seeds of Arabidopsis, tabacco, Zosiagrass, radish, rice and perilla were packed with thin plastic film to be a monolayer of seeds for homogenous irradiation, but also calli of Zosiagrass and Chrysanthemum were placed in the plastic petridish (diameter 5.5cm) with agar medium. They were irradiated with a proton beam of MC-50 cyclotron with various dose ranges of 10 to 5000Gy depend on plant materials and then measured germination rate and early growth of M1 plants. Arabidopsis, tabacco, and Zosiagrass showed little inhibition of germination and early growth at doses tested over than 1000 Gy. In particular, Arabidopsis showed less growth inhibition than 50 % even at dose of 5000Gy. On the other hand, radish, perilla and rice were not only sensitively inhibited at the lower doses, but also linearly decreased with accordance with the increasing irradiation dose. The lethal dose 50 (LD50) for two cultivars of perilla was estimated to be at approximately 25-30Gy. All M1 plants of rice did not growth over than 500Gy. These results indicate that the significant difference in sensitivity or in LD50 to irradiation of MC-50 proton beam was observed among plant species and materials.

  12. Metallographic techniques for evaluation of Thermal Barrier Coatings produced by Electron Beam Physical Vapor Deposition

    International Nuclear Information System (INIS)

    Kelly, Matthew; Singh, Jogender; Todd, Judith; Copley, Steven; Wolfe, Douglas

    2008-01-01

    Thermal Barrier Coatings (TBC) produced by Electron Beam Physical Vapor Deposition (EB-PVD) are primarily applied to critical hot section turbine components. EB-PVD TBC for turbine applications exhibit a complicated structure of porous ceramic columns separated by voids that offers mechanical compliance. Currently there are no standard evaluation methods for evaluating EB-PVD TBC structure quantitatively. This paper proposes a metallographic method for preparing samples and evaluating techniques to quantitatively measure structure. TBC samples were produced and evaluated with the proposed metallographic technique and digital image analysis for columnar grain size and relative intercolumnar porosity. Incorporation of the proposed evaluation technique will increase knowledge of the relation between processing parameters and material properties by incorporating a structural link. Application of this evaluation method will directly benefit areas of quality control, microstructural model development, and reduced development time for process scaling

  13. Characterization of the Teotihuacan mural painting: application of the external particle beam as non destructive technique

    International Nuclear Information System (INIS)

    Martinez, C.; Manzanilla, L.; Ruvalcaba, J.L.; Ontalba, M.A.

    2005-01-01

    The characterization of technical indicators contained in the painting mural should follow a minim methodology from their discovery in the archaeological excavations until their analysis in the laboratory, with the purpose of rescuing diagnostic elements that mark the stages of socio cultural development in the towns. With this spirit it was carried out the present study analyzing some fragments of the Teotihuacan mural painting. The analysis consisted on applying some of the analytical techniques with particle beams used for archaeometry like the Proton induced X-ray emission (PIXE) and the particle elastic backscattering (RBS), due to it is treated of complementary techniques, very sensitive, of multielemental character, but mainly because its are non destructive analytical techniques. (Author)

  14. Accuracy of image-guided radiotherapy of prostate cancer based on the BeamCath urethral catheter technique

    DEFF Research Database (Denmark)

    Poulsen, Per Rugaard; Fokdal, Lars; Petersen, Jørgen B.B.

    2007-01-01

    BACKGROUND AND PURPOSE: To examine the accuracy of the BeamCath urethral catheter technique for prostate localization during radiotherapy. MATERIALS AND METHODS: Sixty-four patients were CT scanned twice with the BeamCath catheter, and once without the catheter. The catheter contains radiopaque...

  15. Formation of large clusters during sputtering of silver

    International Nuclear Information System (INIS)

    Staudt, C.; Heinrich, R.; Wucher, A.

    2000-01-01

    We have studied the formation of polyatomic clusters during sputtering of metal surfaces by keV ion bombardment. Both positively charged (secondary cluster ions) and neutral clusters have been detected in a time-of-flight mass spectrometer under otherwise identical experimental conditions, the sputtered neutrals being post-ionized by single photon absorption using a pulsed 157 nm VUV laser beam. Due to the high achievable laser intensity, the photoionization of all clusters could be saturated, thus enabling a quantitative determination of the respective partial sputtering yields. We find that the relative yield distributions of sputtered clusters are strongly correlated with the total sputtering yield in a way that higher yields lead to higher abundances of large clusters. By using heavy projectile ions (Xe + ) in connection with bombarding energies up to 15 keV, we have been able to detect sputtered neutral silver clusters containing up to about 60 atoms. For cluster sizes above 40 atoms, doubly charged species are shown to be produced in the photoionization process with non-negligible efficiency. From a direct comparison of secondary neutral and ion yields, the ionization probability of sputtered clusters is determined as a function of the cluster size. It is demonstrated that even the largest silver clusters are still predominantly sputtered as neutrals

  16. A large capacity time division multiplexed (TDM) laser beam combining technique enabled by nanosecond speed KTN deflector

    Science.gov (United States)

    Yin, Stuart (Shizhuo); Chao, Ju-Hung; Zhu, Wenbin; Chen, Chang-Jiang; Campbell, Adrian; Henry, Michael; Dubinskiy, Mark; Hoffman, Robert C.

    2017-08-01

    In this paper, we present a novel large capacity (a 1000+ channel) time division multiplexing (TDM) laser beam combining technique by harnessing a state-of-the-art nanosecond speed potassium tantalate niobate (KTN) electro-optic (EO) beam deflector as the time division multiplexer. The major advantages of TDM approach are: (1) large multiplexing capability (over 1000 channels), (2) high spatial beam quality (the combined beam has the same spatial profile as the individual beam), (3) high spectral beam quality (the combined beam has the same spectral width as the individual beam, and (4) insensitive to the phase fluctuation of individual laser because of the nature of the incoherent beam combining. The quantitative analyses show that it is possible to achieve over one hundred kW average power, single aperture, single transverse mode solid state and/or fiber laser by pursuing this innovative beam combining method, which represents a major technical advance in the field of high energy lasers. Such kind of 100+ kW average power diffraction limited beam quality lasers can play an important role in a variety of applications such as laser directed energy weapons (DEW) and large-capacity high-speed laser manufacturing, including cutting, welding, and printing.

  17. The statistics of sputtering

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1993-01-01

    The MARLOWE program was used to study the statistics of sputtering on the example of 1- to 100-keV Au atoms normally incident on static (001) and (111) Au crystals. The yield of sputtered atoms was examined as a function of the impact point of the incident particles (''ions'') on the target surfaces. There were variations on two scales. The effects of the axial and planar channeling of the ions could be traced, the details depending on the orientation of the target and the energies of the ions. Locally, the sputtering yield was very sensitive to the impact point, small changes in position often producing large changes yield. Results indicate strongly that the sputtering yield is a random (''chaotic'') function of the impact point

  18. New technique of skin embedded wire double-sided laser beam welding

    Science.gov (United States)

    Han, Bing; Tao, Wang; Chen, Yanbin

    2017-06-01

    In the aircraft industry, double-sided laser beam welding is an approved method for producing skin-stringer T-joints on aircraft fuselage panels. As for the welding of new generation aluminum-lithium alloys, however, this technique is limited because of high hot cracking susceptibility and strengthening elements' uneven distributions within weld. In the present study, a new technique of skin embedded wire double-sided laser beam welding (LBW) has been developed to fabricate T-joints consisting of 2.0 mm thick 2060-T8/2099-T83 aluminum-lithium alloys using eutectic alloy AA4047 filler wire. Necessary dimension parameters of the novel groove were reasonably designed for achieving crack-free welds. Comparisons were made between the new technique welded T-joint and conventional T-joint mainly on microstructure, hot crack, elements distribution features and mechanical properties within weld. Excellent crack-free microstructure, uniform distribution of silicon and superior tensile properties within weld were found in the new skin embedded wire double-sided LBW T-joints.

  19. Crystal orientation and sample preparation effects on sputtering and lattice damage in 100 keV self-irradiated copper

    International Nuclear Information System (INIS)

    Sprague, J.A.; Malmberg, P.R.; Reynolds, G.W.; Lambert, J.M.; Treado, P.A.; Vincenz, A.M.

    1987-01-01

    Sputtering yields and angular distributions have been measured as functions of sample preparation techniques and incident ion-beam orientation with respect to the crystal axes for 100 keV Cu-ion beams on Cu crystals and polycrystalline samples. The angular distributions have structure requiring an nth order cosine with two Gaussians superimposed to fit the data; strong peaking is observed near the backscatter direction. The yield is dependent on the beam to crystal and beam to polycrystalline-rod axis orientation, on the grain size of the polycrystals and on sample-preparation techniques. Yield measurements vary by as much as a factor of 4. Lattice-damage differences, measured with alpha particle channeling, are much smaller and seem to be saturated by fluences of the order of 1x10 16 /cm 2 . (orig.)

  20. Sputtering and inelastic processes

    International Nuclear Information System (INIS)

    Baranov, I.A.; Tsepelevic, S.O.

    1987-01-01

    Experimental data and models of a new type of material sputtering with ions of relatively high energies due to inelastic (electron) processes are reviewed. This area of investigations began to develop intensively during the latest years. New experimental data of the authors on differential characteristics of ultradisperse gold and americium dioxide layers with fission fragments are given as well. Practical applications of the new sputtering type are considered as well as setup of possibl experiments at heavy multiply charged ion accelerators

  1. Measurement of Gaussian laser beam radius using the knife-edge technique: improvement on data analysis

    International Nuclear Information System (INIS)

    Araujo, Marcos A. de; Silva, Rubens; Lima, Emerson de; Pereira, Daniel P.; Oliveira, Paulo C. de

    2009-01-01

    We revisited the well known Khosrofian and Garetz inversion algorithm [Appl. Opt.22, 3406-3410 (1983)APOPAI0003-6935] that was developed to analyze data obtained by the application of the traveling knife-edge technique. We have analyzed the approximated fitting function that was used for adjusting their experimental data and have found that it is not optimized to work with a full range of the experimentally-measured data. We have numerically calculated a new set of coefficients, which makes the approximated function suitable for a full experimental range, considerably improving the accuracy of the measurement of a radius of a focused Gaussian laser beam

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

    DEFF Research Database (Denmark)

    Muhammad, Hanif; 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...... 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...

  3. Measurements of low density, high velocity flow by electron beam fluorescence technique

    International Nuclear Information System (INIS)

    Soga, Takeo; Takanishi, Masaya; Yasuhara, Michiru

    1981-01-01

    A low density chamber with an electron gun system was made for the measurements of low density, high velocity (high Mach number) flow. This apparatus is a continuous running facility. The number density and the rotational temperature in the underexpanding free jet of nitrogen were measured along the axis of the jet by the electron beam fluorescence technique. The measurements were carried out from the vicinity of the exit of the jet to far downstream of the first Mach disk. Rotational nonequilibrium phenomena were observed in the hypersonic flow field as well as in the shock wave (Mach disk). (author)

  4. Measurement techniques for low emittance tuning and beam dynamics at CESR

    Science.gov (United States)

    Billing, M. G.; Dobbins, J. A.; Forster, M. J.; Kreinick, D. L.; Meller, R. E.; Peterson, D. P.; Ramirez, G. A.; Rendina, M. C.; Rider, N. T.; Sagan, D. C.; Shanks, J.; Sikora, J. P.; Stedinger, M. G.; Strohman, C. R.; Williams, H. A.; Palmer, M. A.; Holtzapple, R. L.; Flanagan, J.

    2018-03-01

    After operating as a High Energy Physics electron-positron collider, the Cornell Electron-positron Storage Ring (CESR) has been converted to become a dedicated synchrotron light source for the Cornell High Energy Synchrotron Source (CHESS). Over the course of several years CESR was adapted for accelerator physics research as a test accelerator, capable of studying topics relevant to future damping rings, colliders and light sources. Initially some specific topics were targeted for accelerator physic research with the storage ring in this mode, labeled CesrTA. These topics included 1) tuning techniques to produce low emittance beams, 2) the study of electron cloud (EC) development in a storage ring and 3) intra-beam scattering effects. The complete conversion of CESR to CesrTA occurred over a several year period, described elsewhere [1–3]. A number of specific instruments were developed for CesrTA. Much of the pre-existing instrumentation was modified to accommodate the scope of these studies and these are described in a companion paper [4]. To complete this research, a number of procedures were developed or modified, often requiring coordinated measurements among different instruments [5]. This paper provides an overview of types of measurements employed for the study of beam dynamics during the operation of CesrTA.

  5. Development of small scale mechanical testing techniques on ion beam irradiated 304 SS

    International Nuclear Information System (INIS)

    Reichardt, A.; Abad, M.D.; Hosemann, P.; Lupinacci, A.; Kacher, J.; Minor, A.; Jiao, Z; Chou, P.

    2015-01-01

    Austenitic stainless steels are widely used for structural components in light water reactors, however uncertainty in their susceptibility to irradiation assisted stress corrosion cracking (IASCC) has made long term performance predictions difficult. In addition, the testing of reactor irradiated materials has proven challenging due to the long irradiation times required, limited sample availability, and unwanted activation. To address these problems, we apply recently developed techniques in nano-indentation and micro-compression testing to small volume samples of 10 dpa proton-beam irradiated 304 stainless steel. Cross sectional nano-indentation was performed on both proton beam irradiated and non-irradiated samples at temperatures ranging from 22 to 300 C. degrees to determine the effects of irradiation and operating temperature on hardening. Micro-compression tests using 2 μm x 2 μm x 5 μm focused-ion beam milled pillars were then performed in situ in an electron microscope to allow for a more accurate look at stress-strain behavior along with real-time observations of localized mechanical deformation. Large sudden slip events and significant increase in yield strength are observed in irradiated micro-compression samples at room temperature. Elevated temperature nano-indentation results reveal the possibility of thermally-activated changes in deformation mechanism for irradiated specimens. Since the deformation mechanism information provided by micro-compression testing can provide valuable information about IASCC susceptibility, future work will involve ex situ micro-compression tests at reactor operating temperature

  6. A technique for measuring an electron beam close-quote s longitudinal phase space with sub-picosecond resolution

    International Nuclear Information System (INIS)

    Crosson, E.R.; Berryman, K.W.; Richman, B.A.; Smith, T.I.; Swent, R.L.

    1996-01-01

    We have developed a technique for measuring the longitudinal phase space distribution of the Stanford Superconducting Accelerator close-quote s (SCA) electron beam which involves applying tomographic techniques to energy spectra taken as a function of the relative phase between the beam and the accelerating field, and optionally, as a function of the strength of a variable dispersion section in the system. The temporal profile of the beam obtained by projecting the inferred distribution onto the time axis is compared with that obtained from interferometric transition radiation measurements. copyright 1996 American Institute of Physics

  7. Study on the preheating duration of Cu{sub 2}SnS{sub 3} thin films using RF magnetron sputtering technique for photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yuchen; He, Jun; Li, Xinran; Chen, Ye; Sun, Lin, E-mail: lsun@ee.ecnu.edu.cn; Yang, Pingxiong; Chu, Junhao

    2016-04-25

    Cu{sub 2}SnS{sub 3} (CTS) thin films are prepared by sulfurization the stacked metallic precursors deposited by raido-frequency magnetron sputtering method on molybdenum-coated soda lime glass substrates. The details of sulfurization process and the effect of preheating duration on the properties of CTS thin films have been investigated. It is found that the content of element tin strongly depend on the preheating duration. X-ray diffraction patterns identify that the CTS thin films exhibit the monoclinic structure. Raman scattering spectra make a further confirmation for the crystal structure. Fourier transform infrared reflectance spectroscopy (FTIR) is first used to study the properties of CTS thin films. The assigned active modes in Raman scattering spectra is consistent with the analysis in FTIR. Morphology analysis reveals long preheating duration would make the quality of films deteriorate. The thin film solar cell (TFSC) fabricated using the CTS absorber layer synthesized at preheating duration of 15 min shows that a power conversion efficiency up to 0.76% for a 0.19 cm{sup 2} area. The electrical characterization of CTS TFSC is first studied by electrochemical impedance spectroscopy, which implies the existence of MoS{sub x} and defects in the CTS/CdS interface. - Highlights: • CTS thin films and solar cells prepared by RF magnetron sputtering. • Preheating duration is a critical way to remain the Sn content in CTS thin film. • XRD, Raman, FTIR and XPS confirmed the single phase of CTS thin film. • The device characterization of CTS solar cell has been systematically investigated.

  8. Improvement of corrosion protection property of Mg-alloy by DLC and Si-DLC coatings with PBII technique and multi-target DC-RF magnetron sputtering

    International Nuclear Information System (INIS)

    Masami, Ikeyama; Setsuo, Nakao; Tsutomu, Sonoda; Junho, Choi

    2009-01-01

    Magnesium alloys have been considered as one of the most promising light weight materials with potential applications for automobile and aircraft components. Their poor corrosion resistance, however, has to date prevented wider usage. Diamond-like carbon (DLC) and silicon-incorporated DLC (Si-DLC) coatings are known to provide a high degree of corrosion protection, and hold accordingly promise for enhancing the corrosion resistance of the magnesium alloys. In this work we have studied the effect of coating conditions of DLC coatings as well as Si incorporation into coating on corrosion resistance, deposited onto AZ91 magnesium alloy substrates by plasma based ion implantation (PBII). The influences of a Ti interlayer beneath the DLC, Si-DLC and Ti incorporated DLC (Ti-DLC) coatings fabricated by multi-target direct-current radio-frequency (DC-RF) magnetron sputtering were also examined on both the adhesion strength and corrosion resistance of the materials. We have also examined the effect of the Si content in the Si-DLC coatings made by magnetron sputtering on the alloys' corrosion resistance. The results of potentiodynamic polarization measurements demonstrate that Si-DLC coating deposited by PBII exhibits the highest corrosion resistance in an aqueous 0.05 M NaCl solution. Although Ti layer is helpful in increasing adhesion between DLC coating and AZ91 substrate, it also influences adversely corrosion protection. The ozone treatment of the magnesium alloy's surface before the formation of coatings has been found to improve both adhesion strength and corrosion resistance.

  9. Improvement of corrosion protection property of Mg-alloy by DLC and Si-DLC coatings with PBII technique and multi-target DC-RF magnetron sputtering

    Science.gov (United States)

    Masami, Ikeyama; Setsuo, Nakao; Tsutomu, Sonoda; Junho, Choi

    2009-05-01

    Magnesium alloys have been considered as one of the most promising light weight materials with potential applications for automobile and aircraft components. Their poor corrosion resistance, however, has to date prevented wider usage. Diamond-like carbon (DLC) and silicon-incorporated DLC (Si-DLC) coatings are known to provide a high degree of corrosion protection, and hold accordingly promise for enhancing the corrosion resistance of the magnesium alloys. In this work we have studied the effect of coating conditions of DLC coatings as well as Si incorporation into coating on corrosion resistance, deposited onto AZ91 magnesium alloy substrates by plasma based ion implantation (PBII). The influences of a Ti interlayer beneath the DLC, Si-DLC and Ti incorporated DLC (Ti-DLC) coatings fabricated by multi-target direct-current radio-frequency (DC-RF) magnetron sputtering were also examined on both the adhesion strength and corrosion resistance of the materials. We have also examined the effect of the Si content in the Si-DLC coatings made by magnetron sputtering on the alloys' corrosion resistance. The results of potentiodynamic polarization measurements demonstrate that Si-DLC coating deposited by PBII exhibits the highest corrosion resistance in an aqueous 0.05 M NaCl solution. Although Ti layer is helpful in increasing adhesion between DLC coating and AZ91 substrate, it also influences adversely corrosion protection. The ozone treatment of the magnesium alloy's surface before the formation of coatings has been found to improve both adhesion strength and corrosion resistance.

  10. New imaging technique based on diffraction of a focused x-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Kazimirov, A [Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States); Kohn, V G [Russian Research Center ' Kurchatov Institute, 123182 Moscow (Russian Federation); Cai, Z-H [Advanced Photon Source, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)], E-mail: ayk7@cornell.edu

    2009-01-07

    We present first experimental results from a new diffraction depth-sensitive imaging technique. It is based on the diffraction of a focused x-ray beam from a crystalline sample and recording the intensity pattern on a high-resolution CCD detector positioned at a focal plane. Structural non-uniformity inside the sample results in a region of enhanced intensity in the diffraction pattern. The technique was applied to study silicon-on-insulator thin layers of various thicknesses which revealed a complex strain profile within the layers. A circular Fresnel zone plate was used as a focusing optic. Incoherent diffuse scattering spreads out of the diffraction plane and results in intensity recorded outside of the focal spot providing a new approach to separately register x-rays scattered coherently and incoherently from the sample. (fast track communication)

  11. Future strategy and puzzles of heavy ion beam mediated technique in genetic improvement of biological bodies

    International Nuclear Information System (INIS)

    Huang Qunce

    2007-01-01

    The 7 research puzzles in the genetic improvement of biological bodies made by ion beam mediated technique, are worth noticed. The technical ideas, including one mediated technique in physics, 2 significant subjects, 3 effective changes, the mediated evidences of 4 aspects and 5 biological characteristics, were particularly put forward according to the existing states in the field. The 2 significant subjects consist of the mechanics of the allogenetic materials entering into the acceptor and they being to be recombined. The 3 effective changes include from studying morphology to genetic laws, from researching M1 generation to the next generations, from determining the single character to the synthetic traits. The mediated evidences of 4 aspects come from morphology, physiology and biochemistry, molecule biology. The 5 biological characteristics are mainly reproduction, development, photosynthesis, bad condition-resistant and quality. (authors)

  12. Initial experience of using an active beam delivery technique at PSI

    International Nuclear Information System (INIS)

    Pedroni, E.; Boehringer, T.; Coray, A.; Egger, E.; Grossmann, M.; Lin Shixiong; Lomax, A.; Goitein, G.; Roser, W.; Schaffner, B.

    1999-01-01

    At PSI a new proton therapy facility has been assembled and commissioned. The major features of the facility are the spot scanning technique and the very compact gantry. The operation of the facility was started in 1997 and the feasibility of the spot scanning technique has been demonstrated in practice with patient treatments. In this report we discuss the usual initial difficulties encountered in the commissioning of a new technology, the very positive preliminary experience with the system and the optimistic expectations for the future. The long range goal of this project is to parallel the recent developments regarding inverse planning for photons with a similar advanced technology optimized for a proton beam. (orig.)

  13. A technique for transferring a patient's smile line to a cone beam computed tomography (CBCT) image.

    Science.gov (United States)

    Bidra, Avinash S

    2014-08-01

    Fixed implant-supported prosthodontic treatment for patients requiring a gingival prosthesis often demands that bone and implant levels be apical to the patient's maximum smile line. This is to avoid the display of the prosthesis-tissue junction (the junction between the gingival prosthesis and natural soft tissues) and prevent esthetic failures. Recording a patient's lip position during maximum smile is invaluable for the treatment planning process. This article presents a simple technique for clinically recording and transferring the patient's maximum smile line to cone beam computed tomography (CBCT) images for analysis. The technique can help clinicians accurately determine the need for and amount of bone reduction required with respect to the maximum smile line and place implants in optimal positions. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. Metal oxide collectors for storing matter technique applied in secondary ion mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Miśnik, Maciej [Institute of Tele and Radio Technology, ul. Ratuszowa 11, 03-450 Warszawa (Poland); Gdańsk University of Technology (Poland); Konarski, Piotr [Institute of Tele and Radio Technology, ul. Ratuszowa 11, 03-450 Warszawa (Poland); Zawada, Aleksander [Institute of Tele and Radio Technology, ul. Ratuszowa 11, 03-450 Warszawa (Poland); Military University of Technology, Warszawa (Poland)

    2016-03-15

    We present results of the use of metal and metal oxide substrates that serve as collectors in ‘storing matter’, the quantitative technique of secondary ion mass spectrometry (SIMS). This technique allows separating the two base processes of secondary ion formation in SIMS. Namely, the process of ion sputtering is separated from the process of ionisation. The technique allows sputtering of the analysed sample and storing the sputtered material, with sub-monolayer coverage, onto a collector surface. Such deposits can be then analysed by SIMS, and as a result, the so called ‘matrix effects’ are significantly reduced. We perform deposition of the sputtered material onto Ti and Cu substrates and also onto metal oxide substrates as molybdenum, titanium, tin and indium oxides. The process of sputtering is carried within the same vacuum chamber where the SIMS analysis of the collected material is performed. For sputtering and SIMS analysis of the deposited material we use 5 keV Ar{sup +} beam of 500 nA. The presented results are obtained with the use of stationary collectors. Here we present a case study of chromium. The obtained results show that the molybdenum and titanium oxide substrates used as collectors increase useful yield by two orders, with respect to such pure elemental collectors as Cu and Ti. Here we define useful yield as a ratio of the number of detected secondary ions during SIMS analysis and the number of atoms sputtered during the deposition process.

  15. Analysis and modification of blue sapphires from Rwanda by ion beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bootkul, D., E-mail: mo_duangkhae@hotmail.com [Department of General Science - Gems & Jewelry, Faculty of Science, Srinakharinwirot University, Bangkok 10110 (Thailand); Chaiwai, C.; Tippawan, U. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Wanthanachaisaeng, B. [Gems Enhancement Research Unit, Faculty of Gems, Burapha University, Chanthaburi Campus, Chanthaburi 22170 (Thailand); Intarasiri, S., E-mail: saweat@gmail.com [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2015-12-15

    Highlights: • Ion beam analysis is an effective method for detecting trace elements. • Ion beam treatment is able to improve optical and color appearances of the blue sapphire from Rwanda. • These alternative methods can be extended to jewelry industry for large scale application. - Abstract: Blue sapphire is categorised in a corundum (Al{sub 2}O{sub 3}) group. The gems of this group are always amazed by their beauties and thus having high value. In this study, blue sapphires from Rwanda, recently came to Thai gemstone industry, are chosen for investigations. On one hand, we have applied Particle Induced X-ray Emission (PIXE), which is a highly sensitive and precise analytical technique that can be used to identify and quantify trace elements, for chemical analysis of the sapphires. Here we have found that the major element of blue sapphires from Rwanda is Al with trace elements such as Fe, Ti, Cr, Ga and Mg as are commonly found in normal blue sapphire. On the other hand, we have applied low and medium ion implantations for color improvement of the sapphire. It seems that a high amount of energy transferring during cascade collisions have altered the gems properties. We have clearly seen that the blue color of the sapphires have been intensified after nitrogen ion bombardment. In addition, the gems were also having more transparent and luster. The UV–Vis–NIR measurement detected the modification of their absorption properties, implying of the blue color increasing. Here the mechanism of these modifications is postulated and reported. In any point of view, the bombardment by using nitrogen ion beam is a promising technique for quality improvement of the blue sapphire from Rwanda.

  16. Analysis and modification of blue sapphires from Rwanda by ion beam techniques

    International Nuclear Information System (INIS)

    Bootkul, D.; Chaiwai, C.; Tippawan, U.; Wanthanachaisaeng, B.; Intarasiri, S.

    2015-01-01

    Highlights: • Ion beam analysis is an effective method for detecting trace elements. • Ion beam treatment is able to improve optical and color appearances of the blue sapphire from Rwanda. • These alternative methods can be extended to jewelry industry for large scale application. - Abstract: Blue sapphire is categorised in a corundum (Al_2O_3) group. The gems of this group are always amazed by their beauties and thus having high value. In this study, blue sapphires from Rwanda, recently came to Thai gemstone industry, are chosen for investigations. On one hand, we have applied Particle Induced X-ray Emission (PIXE), which is a highly sensitive and precise analytical technique that can be used to identify and quantify trace elements, for chemical analysis of the sapphires. Here we have found that the major element of blue sapphires from Rwanda is Al with trace elements such as Fe, Ti, Cr, Ga and Mg as are commonly found in normal blue sapphire. On the other hand, we have applied low and medium ion implantations for color improvement of the sapphire. It seems that a high amount of energy transferring during cascade collisions have altered the gems properties. We have clearly seen that the blue color of the sapphires have been intensified after nitrogen ion bombardment. In addition, the gems were also having more transparent and luster. The UV–Vis–NIR measurement detected the modification of their absorption properties, implying of the blue color increasing. Here the mechanism of these modifications is postulated and reported. In any point of view, the bombardment by using nitrogen ion beam is a promising technique for quality improvement of the blue sapphire from Rwanda.

  17. Novel technique for injecting and extracting beams in a circular hadron accelerator without using septum magnets

    Directory of Open Access Journals (Sweden)

    Andrea Franchi

    2015-07-01

    Full Text Available With a few exceptions, all on-axis injection and extraction schemes implemented in circular particle accelerators, synchrotrons, and storage rings, make use of magnetic and electrostatic septa with systems of slow-pulsing dipoles acting on tens of thousands of turns and fast-pulsing dipoles on just a few. The dipoles create a closed orbit deformation around the septa, usually referred to as an orbit bump. A new approach is presented which obviates the need for the septum deflectors. Fast-pulsing elements are still required, but their strength can be minimized by choosing appropriate local accelerator optics. This technique should increase the beam clearance and reduce the usually high radiation levels found around the septa and also reduce the machine impedance introduced by the fast-pulsing dipoles. The basis of the technique is the creation of stable islands around stable fixed points in horizontal phase space. The trajectories of these islands may then be adjusted to match the position and angle of the incoming or outgoing beam.

  18. Recoil separators for radiative capture using radioactive ion beams. Recent advances and detection techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, Chris [TRIUMF, Vancouver, BC (Canada); Greife, Uwe; Hager, Ulrike [Colorado School of Mines, Golden, CO (United States)

    2014-06-15

    Radiative capture reactions involving the fusion of hydrogen or helium are ubiquitous in the stellar history of the universe, and are some of the most important reactions in the processes that govern nucleosynthesis and energy generation in both static and explosive scenarios. However, radiative capture reactions pose some of the most difficult experimental challenges due to extremely small cross sections. With the advent of recoil separators and techniques in inverse kinematics, it is now possible to measure radiative capture reactions on very short-lived radioactive nuclei, and in the presence of high experimental backgrounds. In this paper we review the experimental needs for making measurements of astrophysical importance on radiative capture reactions. We also review some of the important historical advances in the field of recoil separators as well as describe current techniques and performance milestones, including descriptions of some of the separators most recently working at radioactive ion beam facilities, such as DRAGON at TRIUMF and the DRS at the Holifield Radioactive Ion Beam Facility. We will also summarize some of the scientific highlight measurements at the RIB facilities. (orig.)

  19. Implantation, recoil implantation, and sputtering

    International Nuclear Information System (INIS)

    Kelly, R.

    1984-01-01

    Underlying ion-beam modification of surfaces is the more basic subject of particle-surface interaction. The ideas can be grouped into forward and backward features, i.e. those affecting the interior of the target and those leading to particle expulsion. Forward effects include the stopping of the incident particles and the deposition of energy, both governed by integral equations which are easily set up but difficult to solve. Closely related is recoil implantation where emphasis is placed not on the stopping of the incident particles but on their interaction with target atoms with resulting implantation of these atoms. Backward effects, all of which are denoted as sputtering, are in general either of collisional, thermal, electronic, or exfoliational origin. (Auth.)

  20. The installation of a sputter cone ion source for the production of tritium ion beams at the Minnesota M.P. tandem

    International Nuclear Information System (INIS)

    Broadhurst, J.H.; Blair, J.M.; Brown, R.E.

    1977-01-01

    A description of the techniques developed for the utilization of a radioactive material in an ion source within the environment of a nuclear physics laboratory. The precautions taken to control the spread of contamination, to minimize the radioactive material inventory and to effect routine maintenance are described

  1. Advanced capabilities and applications of a sputter-RBS system

    International Nuclear Information System (INIS)

    Brijs, B.; Deleu, J.; Beyer, G.; Vandervorst, W.

    1999-01-01

    In previous experiments, sputter-RBS 1 has proven to be an ideal tool to study the interaction of low energy ions. This contribution employs the same methodology to identify surface contamination induced during sputtering and to the determine absolute sputter yields. In the first experiment ERDA analysis was used to study the evolution of Hydrogen contamination during sputter-RBS experiments. Since the determination of Hydrogen concentration in very thin near surface layers is frequently limited by the presence of a strong surface peak of Hydrogen originating from adsorbed contamination of the residual vacuum, removal of this contamination would increase the sensitivity for Hydrogen detection in the near sub surface drastically. Therefore low energy (12 keV) Argon sputtering was used to remove the Hydrogen surface peak. However enhanced Hydrogen adsorption was observed related to the Ar dose. This experiment shows that severe vacuum conditions and the use of high current densities/sputter yields are a prerequisite for an efficient detection of Hydrogen in the near surface layers. In the second experiment, an attempt was made to determine the sputter yield of Cu during low energy (12 keV) Oxygen bombardment. In order to determine the accumulated dose of the low energy ion beam, a separate Faraday cup in combination with a remote controlled current have been added to the existing sputter-RBS set-up. Alternating sputtering and RBS analysis seem to be an adequate tool for the determination of the absolute sputter yield of Cu and this as well in the as under steady state conditions

  2. Using the in situ lift-out technique to prepare TEM specimens on a single-beam FIB instrument

    International Nuclear Information System (INIS)

    Lekstrom, M; McLachlan, M A; Husain, S; McComb, D W; Shollock, B A

    2008-01-01

    Transmission electron microscope (TEM) specimens are today routinely prepared using focussed ion beam (FIB) instruments. Specifically, the lift-out method has become an increasingly popular technique and involves removing thin cross-sections from site-specific locations and transferring them to a TEM grid. This lift-out process can either be performed ex situ or in situ. The latter is mainly carried out on combined dual-beam FIB and scanning electron microscope (SEM) systems whereas conventional single-beam instruments often are limited to the traditional ex situ method. It is nevertheless desirable to enhance the capabilities of existing single-beam instruments to allow for in situ lift-out preparation to be performed since this technique offers a number of advantages over the older ex situ method. A single-beam FIB instrument was therefore modified to incorporate an in situ micromanipulator fitted with a tungsten needle, which can be attached to a cut-out FIB section using ion beam induced platinum deposition. This article addresses the issues of using an ion beam to monitor the in situ manipulation process as well as approaches that can be used to create stronger platinum welds between two objects, and finally, views on how to limit the extent of ion beam damage to the specimen surface.

  3. Quantitative sputter profiling at surfaces and interfaces

    International Nuclear Information System (INIS)

    Kirschner, J.; Etzkorn, H.W.

    1981-01-01

    The key problem in quantitative sputter profiling, that of a sliding depth scale has been solved by combined Auger/X-ray microanalysis. By means of this technique and for the model system Ge/Si (amorphous) the following questions are treated quantitatively: shape of the sputter profiles when sputtering through an interface and origin of their asymmetry; precise location of the interface plane on the depth profile; broadening effects due to limited depth of information and their correction; origin and amount of bombardment induced broadening for different primary ions and energies; depth dependence of the broadening, and basic limits to depth resolution. Comparisons are made to recent theoretical calculations based on recoil mixing in the collision cascade and very good agreement is found

  4. MODELLING THE DELAMINATION FAILURE ALONG THE CFRP-CFST BEAM INTERACTION SURFACE USING DIFFERENT FINITE ELEMENT TECHNIQUES

    Directory of Open Access Journals (Sweden)

    AHMED W. AL-ZAND

    2017-01-01

    Full Text Available Nonlinear finite element (FE models are prepared to investigate the behaviour of concrete-filled steel tube (CFST beams strengthened by carbon fibre reinforced polymer (CFRP sheets. The beams are strengthened from the bottom side only by varied sheet lengths (full and partial beam lengths and then subjected to ultimate flexural loads. Three surface interaction techniques are used to implement the bonding behaviour between the steel tube and the CFRP sheet, namely, full tie interaction (TI, cohesive element (CE and cohesive behaviour (CB techniques using ABAQUS software. Results of the comparison between the FE analysis and existing experimental study confirm that the FE models with the TI technique could be applicable for beams strengthened by CFRP sheets with a full wrapping length; the technique could not accurately implement the CFRP delamination failure, which occurred for beams with a partial wrapping length. Meanwhile, the FE models with the CE and CB techniques are applicable in the implementation of both CFRP failures (rapture and delamination for both full and partial wrapping lengths, respectively. Where, the ultimate loads' ratios achieved by the FE models using TI, CE and CB techniques about 1.122, 1.047 and 1.045, respectively, comparing to the results of existing experimental tests.

  5. Sputtering yields of carbon based materials under high particle flux with low energy

    Science.gov (United States)

    Nakamura, K.; Nagase, A.; Dairaku, M.; Akiba, M.; Araki, M.; Okumura, Y.

    1995-04-01

    A new ion source which can produce high particle flux beams at low energies has been developed. This paper presents preliminary results on the sputtering yield of the carbon fiber reinforced composites (CFCs) measured with the new ion source. The sputtering yields of 1D and 2D CFCs, which are candidate materials for the divertor armour tiles, have been measured by the weight loss method under the hydrogen and deuterium particle fluxes of 2 ˜ 7 × 10 20/m 2 s at 50 ˜ 150 eV. Preferential sputtering of the matrix was observed on CFCs which included the matrix of 40 ˜ 60 w%. The energy dependence of the sputtering yields was weak. The sputtering yields of CFCs normally irradiated with deuterium beam were from 0.073 to 0.095, and were around three times larger than those with hydrogen beam.

  6. Sputtering yields of carbon based materials under high particle flux with low energy

    International Nuclear Information System (INIS)

    Nakamura, K.; Nagase, A.; Dairaku, M.; Akiba, M.; Araki, M.; Okumura, Y.

    1995-01-01

    A new ion source which can produce high particle flux beams at low energies has been developed. This paper presents preliminary results on the sputtering yield of the carbon fiber reinforced composites (CFCs) measured with the new ion source. The sputtering yields of 1D and 2D CFCs, which are candidate materials for the divertor armour tiles, have been measured by the weight loss method under the hydrogen and deuterium particle fluxes of 2 similar 7x10 20 /m 2 s at 50 similar 150 eV. Preferential sputtering of the matrix was observed on CFCs which included the matrix of 40 similar 60 w%. The energy dependence of the sputtering yields was weak. The sputtering yields of CFCs normally irradiated with deuterium beam were from 0.073 to 0.095, and were around three times larger than those with hydrogen beam. ((orig.))

  7. Implantation, recoil implantation, and sputtering

    International Nuclear Information System (INIS)

    Kelly, R.

    1984-01-01

    The implantation and sputtering mechanisms which are relevant to ion bombardment of surfaces are described. These are: collision, thermal, electronic and photon-induced sputtering. 135 refs.; 36 figs.; 9 tabs

  8. Influence of the surface topography, morphology and structure on magnetic properties of ion beam sputtered iron layers, Fe/Cr/Fe- and Fe/MgO/Fe multilayers; Untersuchung der Morphologie und magnetische Eigenschaften von ionenstrahl-gesputterten Eisen-Einzelschichten, Fe/Cr/Fe- und Fe/MgO/Fe-Schichtsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Steeb, Alexandra

    2007-04-05

    In this PhD Thesis, the influence of the surface topography, morphology and structure on magnetic properties of ion beam sputtered iron layers on GaAs is examined. To analyze the structure of the produced iron films, low energy electron diffraction and scanning tunneling microscopy is employed. The utilized methods to investigate the magnetic properties are Kerr- and SQUID-magnetometry and ferromagnetic resonance. It is demonstrated that on untreated as well as on presputtered and heated GaAs substrates the sputtered iron films grow epitaxially. The least surface roughness of 1 A exhibit iron films grown on untreated GaAs, while iron films on heated GaAs have the highest roughness of 30 A. The largest crystal anisotropy constant is found for the presputtered GaAs/Fe-System. For this preparation method, two monolayers of iron are determined to be magnetically dead layers. At a film thickness of 100 A, 83% of the value for saturation magnetization of bulk iron are achieved. The small observed FMR-linewidths confirm the good bulk properties of the ion beam sputtered iron. Furthermore, an antiferromagnetic interlayer exchange coupling in sputtered Fe/Cr/Fe-films was achieved. For a thickness of 12 to 17 A of the chrome interlayer, a coupling strength up to 0.2 mJ/m{sup 2} is found. To account for the small coupling strength, a strong intermixing at the interface is assumed. Finally, epitaxial Fe/MgO/Fe/FeMn multilayers are deposited on GaAs. After the structuring, it is possible to detect tunneling processes in the tunneling contacts with current-voltage measurements. The tunnel magneto resistance values of 2% are small, which can be explained by the absence of sharp, well-defined interfaces between the Fe/FeMn and the Fe/MgO interfaces. These results demonstrate, that analog to MBE the ion beam sputtering method realizes good magnetic bulk properties. However, interface sensitive phenomena are weakened because of a strong intermixing at the interfaces. (orig.)

  9. Characterization techniques for the high-brightness particle beams of the Advanced Photon Source (APS)

    International Nuclear Information System (INIS)

    Lumpkin, A.H.

    1993-01-01

    The Advanced Photon Source (APS) will be a third-generation synchrotron radiation (SR) user facility in the hard x-ray regime (10--100 keV). The design objectives for the 7-GeV storage ring include a positron beam natural emittance of 8 x 10 -9 m-rad at an average current of 100 mA. Proposed methods for measuring the transverse and longitudinal profiles will be described. Additionally, a research and development effort using an rf gun as a low-emittance source of electrons for injection into the 200- to 650-MeV linac subsystem is underway. This latter system is projected to produce electron beams with a normalized, rms emittance of ∼2 π mm-mrad at peak currents of near one hundred amps. This interesting characterization problem will also be briefly discussed. The combination of both source types within one laboratory facility will stimulate the development of diagnostic techniques in these parameter spaces

  10. Reliability study of a prestressed concrete beam by Monte Carlo techniques

    International Nuclear Information System (INIS)

    Floris, C.; Migliacci, A.

    1987-01-01

    The safety of a prestressed beam is studied at the third probabilistic level and so calculating the probability of failure (P f ) under known loads. Since the beam is simply supported and subject only to loads perpendicular to its axis, only bending and shear loads are present. Since the ratio between the span and the clear height is over 20 with thus a very considerable shear span, it can be assumed that failure occurs entirely due to the bending moment, with shear having no effect. In order to calculate P f the probability density function (p.d.f.) have to be known both for the stress moment and the resisting moment. Attention here is focused on the construction of the latter. It is shown that it is practically impossible to find the required function analytically. On the other hand, numerical simulation with the help of a computer is particularly convenient. The so-called Monte Carlo techniques were chosen: they are based on the extraction of random numbers and are thus very suitable for simulating random events and quantities. (orig./HP)

  11. Optimisation of 12 MeV electron beam simulation using variance reduction technique

    International Nuclear Information System (INIS)

    Jayamani, J; Aziz, M Z Abdul; Termizi, N A S Mohd; Kamarulzaman, F N Mohd

    2017-01-01

    Monte Carlo (MC) simulation for electron beam radiotherapy consumes a long computation time. An algorithm called variance reduction technique (VRT) in MC was implemented to speed up this duration. This work focused on optimisation of VRT parameter which refers to electron range rejection and particle history. EGSnrc MC source code was used to simulate (BEAMnrc code) and validate (DOSXYZnrc code) the Siemens Primus linear accelerator model with the non-VRT parameter. The validated MC model simulation was repeated by applying VRT parameter (electron range rejection) that controlled by global electron cut-off energy 1,2 and 5 MeV using 20 × 10 7 particle history. 5 MeV range rejection generated the fastest MC simulation with 50% reduction in computation time compared to non-VRT simulation. Thus, 5 MeV electron range rejection utilized in particle history analysis ranged from 7.5 × 10 7 to 20 × 10 7 . In this study, 5 MeV electron cut-off with 10 × 10 7 particle history, the simulation was four times faster than non-VRT calculation with 1% deviation. Proper understanding and use of VRT can significantly reduce MC electron beam calculation duration at the same time preserving its accuracy. (paper)

  12. All-optical optoacoustic microscopy based on probe beam deflection technique

    Directory of Open Access Journals (Sweden)

    Saher M. Maswadi

    2016-09-01

    Full Text Available Optoacoustic (OA microscopy using an all-optical system based on the probe beam deflection technique (PBDT for detection of laser-induced acoustic signals was investigated as an alternative to conventional piezoelectric transducers. PBDT provides a number of advantages for OA microscopy including (i efficient coupling of laser excitation energy to the samples being imaged through the probing laser beam, (ii undistorted coupling of acoustic waves to the detector without the need for separation of the optical and acoustic paths, (iii high sensitivity and (iv ultrawide bandwidth. Because of the unimpeded optical path in PBDT, diffraction-limited lateral resolution can be readily achieved. The sensitivity of the current PBDT sensor of 22 μV/Pa and its noise equivalent pressure (NEP of 11.4 Pa are comparable with these parameters of the optical micro-ring resonator and commercial piezoelectric ultrasonic transducers. Benefits of the present prototype OA microscope were demonstrated by successfully resolving micron-size details in histological sections of cardiac muscle.

  13. All-optical optoacoustic microscopy based on probe beam deflection technique.

    Science.gov (United States)

    Maswadi, Saher M; Ibey, Bennett L; Roth, Caleb C; Tsyboulski, Dmitri A; Beier, Hope T; Glickman, Randolph D; Oraevsky, Alexander A

    2016-09-01

    Optoacoustic (OA) microscopy using an all-optical system based on the probe beam deflection technique (PBDT) for detection of laser-induced acoustic signals was investigated as an alternative to conventional piezoelectric transducers. PBDT provides a number of advantages for OA microscopy including (i) efficient coupling of laser excitation energy to the samples being imaged through the probing laser beam, (ii) undistorted coupling of acoustic waves to the detector without the need for separation of the optical and acoustic paths, (iii) high sensitivity and (iv) ultrawide bandwidth. Because of the unimpeded optical path in PBDT, diffraction-limited lateral resolution can be readily achieved. The sensitivity of the current PBDT sensor of 22 μV/Pa and its noise equivalent pressure (NEP) of 11.4 Pa are comparable with these parameters of the optical micro-ring resonator and commercial piezoelectric ultrasonic transducers. Benefits of the present prototype OA microscope were demonstrated by successfully resolving micron-size details in histological sections of cardiac muscle.

  14. Comparison of the NPL water calorimeter with other dosimetric techniques for high energy photon beams

    International Nuclear Information System (INIS)

    Rosser, K.E.; Williams, A.J.

    1999-01-01

    At present, the primary standard of absorbed dose to water at NPL in high energy photon beams is a graphite calorimeter. However the quantity of interest in radiation dosimetry is absorbed dose to water. Therefore, a new absorbed dose to water standard based on water calorimetry is being developed at NPL. The calorimeter operates at 4 deg. C, with temperature control being provided by a combination of liquid and air cooling. The sealed glass inner vessel of the calorimeter has been designed to minimise the effect of non-water materials on the measurement of absorbed dose. Measurements of absorbed dose to water made in 6, 10 and 19 MV photon beams agreed within the measurement uncertainties with those determined using the primary standard graphite calorimeter. Also the absorbed dose to water measured using the water calorimeter agrees with that based on the air kerma standards for 60 Co γ-radiation within the uncertainties. The development of the water calorimeter will lead to a very robust dosimetry system at NPL, where the absorbed dose to water can be determined using three independent techniques. (author)

  15. Physics of ion sputtering

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1984-04-01

    The ejection of atoms by the ion bombardment of solids is discussed in terms of linear collision cascade theory. A simple argument describes the energies of the ejecta, but elaborate models are required to obtain accurate sputtering yields and related quantities. These include transport theoretical models based on linearized Boltzmann equations, computer simulation models based on the binary collision approximation, and classical many-body dynamical models. The role of each kind of model is discussed. Several aspects of sputtering are illustrated by results from the simulation code MARLOWE. 20 references, 6 figures

  16. Application of wire beam electrode technique to investigate initiation and propagation of rebar corrosion

    International Nuclear Information System (INIS)

    Shi, Wei; Dong, Ze Hua; Kong, De Jie; Guo, Xing Peng

    2013-01-01

    Multi-electrode technique named as wire beam electrode (WBE) was used to study pitting corrosion of rebar under concrete cover. When WBE embedded mortar sample was immersed in NaCl solution, uneven distributions of galvanic current and open circuit potential (OCP) on the WBE were observed due to the initiation of pitting corrosion. The following oxygen depletion in mortar facilitated the negative shift of the OCP and the smoothing of the current and potential distributions. Wetting–drying cycle experiments showed that corrosion products instead of oxygen in wet mortar specimen sustained the propagation of pitting corrosion due to Fe (III) taking part in cathodic depolarization during oxygen-deficient wet period, which was confirmed by micro-Raman spectroscopy. In addition, new pitting corrosion occurred mainly near the corrosion products, leading to preferentially horizontal propagation of rust layer on the WBE. A localized corrosion factor was further presented to quantify the localised corrosion based on galvanic current maps

  17. Application of wire beam electrode technique to investigate initiation and propagation of rebar corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wei; Dong, Ze Hua, E-mail: zehua.dong@gmail.com; Kong, De Jie; Guo, Xing Peng

    2013-06-15

    Multi-electrode technique named as wire beam electrode (WBE) was used to study pitting corrosion of rebar under concrete cover. When WBE embedded mortar sample was immersed in NaCl solution, uneven distributions of galvanic current and open circuit potential (OCP) on the WBE were observed due to the initiation of pitting corrosion. The following oxygen depletion in mortar facilitated the negative shift of the OCP and the smoothing of the current and potential distributions. Wetting–drying cycle experiments showed that corrosion products instead of oxygen in wet mortar specimen sustained the propagation of pitting corrosion due to Fe (III) taking part in cathodic depolarization during oxygen-deficient wet period, which was confirmed by micro-Raman spectroscopy. In addition, new pitting corrosion occurred mainly near the corrosion products, leading to preferentially horizontal propagation of rust layer on the WBE. A localized corrosion factor was further presented to quantify the localised corrosion based on galvanic current maps.

  18. Characterization of natural and modified zeolites using ion beam analysis techniques

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, E. [Instituto de Fisica, Departamento de Fisica Experimental, Universidad Nacional Autonoma de Mexico, Apdo. Postal 20-364, 01000 (Mexico)], E-mail: andrade@fisica.unam.mx; Solis, C. [Instituto de Fisica, Departamento de Fisica Experimental, Universidad Nacional Autonoma de Mexico, Apdo. Postal 20-364, 01000 (Mexico); Aceves, J.M.; Miranda, R. [Facultad de Estudios Superiores Cuautitlan Itzcalli, Departamento de Quimica, Universidad Nacional Autonoma de Mexico, 1 de Mayo S/N, Cuatitlan Itzcalli, Edo. de Mexico, C.P. 74540 (Mexico); Cruz, J. [Instituto de Fisica, Departamento de Fisica Experimental, Universidad Nacional Autonoma de Mexico, Apdo. Postal 20-364, 01000 (Mexico); Rocha, M.F. [Escuela Superior de Ingenieria Mecanica y Electrica, Instituto Politecnico Nacional, U.P. ' Adolfo Lopez Mateos' , Zacatenco, Del. Gustavo A. Madero, Mexico D.F. 07738 (Mexico); Zavala, E.P. [Instituto de Fisica, Departamento de Fisica Experimental, Universidad Nacional Autonoma de Mexico, Apdo. Postal 20-364, 01000 (Mexico)

    2008-05-15

    Zeolites are very important materials in catalytic and industrial processes. Natural, modified and synthetic zeolites have a wide range of uses because of their good adsorption, ion exchange capacity and catalytic properties. Mexico is an import source of natural zeolites, however their utilization in the natural form is limited due to the presence of trace metallic impurities. For example, metals such as vanadium and chromium inhibit the elimination of sulfur in hydrocarbons. Therefore, it is important to know the precise composition of the zeolite material. In this work, we report the elemental characterization of zeolites using various IBA techniques. {sup 3}He{sup +} and {sup 2}H{sup +} beams were used to measure the major element concentrations (Si, Al, O, C) by RBS and NRA. PIXE and SEM-EDS were used to measure the total trace element content (V, Cr, Fe, Ni, Cu, Zn, Rb, Sr, Zr, Pb, etc). Additionally, XRD was used to study the zeolite crystal structure.

  19. Applications of factor analysis to electron and ion beam surface techniques

    International Nuclear Information System (INIS)

    Solomon, J.S.

    1987-01-01

    Factor analysis, a mathematical technique for extracting chemical information from matrices of data, is used to enhance Auger electron spectroscopy (AES), core level electron energy loss spectroscopy (EELS), ion scattering spectroscopy (ISS), and secondary ion mass spectroscopy (SIMS) in studies of interfaces, thin films, and surfaces. Several examples of factor analysis enhancement of chemical bonding variations in thin films and at interfaces studied with AES and SIMS are presented. Factor analysis is also shown to be of great benefit in quantifying electron and ion beam doses required to induce surface damage. Finally, examples are presented of the use of factor analysis to reconstruct elemental profiles when peaks of interest overlap each other during the course of depth profile analysis. (author)

  20. Novel method for the production of spin-aligned RI beams in projectile fragmentation reaction with the dispersion matching technique

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Y., E-mail: yuichikawa@phys.titech.ac.jp [Tokyo Institute of Technology, Department of Physics (Japan); Ueno, H. [RIKEN Nishina Center (Japan); Ishii, Y. [Tokyo Institute of Technology, Department of Physics (Japan); Furukawa, T. [Tokyo Metropolitan University, Department of Physics (Japan); Yoshimi, A. [Okayama University, Research Core for Extreme Quantum World (Japan); Kameda, D.; Watanabe, H.; Aoi, N. [RIKEN Nishina Center (Japan); Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan); Balabanski, D. L. [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energy (Bulgaria); Chevrier, R.; Daugas, J. M. [CEA, DAM, DIF (France); Fukuda, N. [RIKEN Nishina Center (Japan); Georgiev, G. [CSNSM, IN2P3-CNRS, Universite Paris-sud (France); Hayashi, H.; Iijima, H. [Tokyo Institute of Technology, Department of Physics (Japan); Inabe, N. [RIKEN Nishina Center (Japan); Inoue, T. [Tokyo Institute of Technology, Department of Physics (Japan); Ishihara, M.; Kubo, T. [RIKEN Nishina Center (Japan); and others

    2013-05-15

    A novel method to produce spin-aligned rare-isotope (RI) beam has been developed, that is the two-step projectile fragmentation method with a technique of dispersion matching. The present method was verified in an experiment at the RIKEN RIBF, where an RI beam of {sup 32}Al with spin alignment of 8(1) % was successfully produced from a primary beam of {sup 48}Ca, with {sup 33}Al as an intermediate nucleus. Figure of merit of the present method was found to be improved by a factor larger than 50 compared with a conventional method employing single-step projectile fragmentation.

  1. A new strategy for wear and corrosion measurements using ion beam based techniques

    International Nuclear Information System (INIS)

    Dudu, D.; Popa, V.; Racolta, P.M.; Voiculescu, Dana

    2001-01-01

    An efficient and precise method for wear testing is Thin Layer Activation (TLA), which is based on the production of a thin layer of radioisotopes in the component surface by bombardment with a charged particle beam. These radioisotopes decay by emitting a characteristic gamma radiation that can be detected with thallium activated sodium iodide NaI(Tl) detectors. Since the material loss due to wear or corrosion is directly proportional to the loss in radioactivity of the activated surface, the wear/corrosion can be monitored in real time. Alternatively, the increase of the activity of the removed material debris collected in an oil bath of engine or in a filter also gives a measure of wear. The application of TLA and UTLA (ultra TLA - by recoil implantation) techniques presupposes establishing the optimum working and measuring conditions for the following steps: irradiation, post irradiation, and 'in situ' measurements. Having in view the diversity of components subjected to wear or corrosion to TLA-based investigations, dedicated beam lines for in-air or vacuum irradiation and translating/rotating target holders were developed by the U-120 Cyclotron of IFIN-HH. The modified IFIN-HH U-120 cyclotron from Bucharest is a classical variable energy machine that can accelerate protons up to 14 MeV, deuterons up to 13.5 MeV, and alpha particles up to 27 MeV. At this machine, TLA has mainly been used for studies of various parts of running machines on test benches such as piston - rings and linear cylinders. Also lubricant characterization studies were conducted here. The main advantage of TLA compared to conventional techniques for wear measurements is its ability to perform continuous in situ wear measurements of engine components, such as cylinder liners and piston rings, without the need to dismantle the components investigated. In addition high wear sensitivity and resolution of wear down to nano meters dimensions is guaranteed. Although the level of activity used in

  2. Laser sputtering. Pt. 1

    International Nuclear Information System (INIS)

    Kelly, R.; Cuomo, J.J.; Leary, P.A.; Rothenburg, J.E.; Braren, B.E.; Aliotta, C.F.

    1985-01-01

    Irradiation, i.e. bombardment, with 193 nm laser pulses having an energy fluence of 2.5 J/cm 2 and a duration of proportional12 ns leads to rapid sputtering with Au, Al 2 O 3 , MgO, MgO.Al 2 O 3 , SiO 2 , glass, and LaB 6 , relatively slow sputtering with MgF 2 and diamond, and mainly thermal-stress cracking with W. Scanning electron microscopy (SEM) suggests that the mechanism for the sputtering of Au in either vacuum or air is one based on the hydrodynamics of molten Au, while an SEM-derived surface temperature estimate confirms that thermal sputtering (which might have been expected) is not possible. SEM with W shows that the near total lack of material removal is due to the thermal-stress cracking not leading to completed exfoliation, together with the surface temperature being too low for either hydrodynamical or thermal processes. Corresponding SEM with Al 2 O 3 shows, in the case of specimens bombarded in vacuum, topography of such a type that all mechanisms except electronic ones can be ruled out. The topography of Al 2 O 3 or other oxides bombarded in air through a mask is somewhat different, showing craters as for vacuum bombardments but ones which have a cone-like pattern on the bottom. (orig.)

  3. Robust breathing signal extraction from cone beam CT projections based on adaptive and global optimization techniques

    International Nuclear Information System (INIS)

    Chao, Ming; Yuan, Yading; Rosenzweig, Kenneth E; Lo, Yeh-Chi; Wei, Jie; Li, Tianfang

    2016-01-01

    We present a study of extracting respiratory signals from cone beam computed tomography (CBCT) projections within the framework of the Amsterdam Shroud (AS) technique. Acquired prior to the radiotherapy treatment, CBCT projections were preprocessed for contrast enhancement by converting the original intensity images to attenuation images with which the AS image was created. An adaptive robust z-normalization filtering was applied to further augment the weak oscillating structures locally. From the enhanced AS image, the respiratory signal was extracted using a two-step optimization approach to effectively reveal the large-scale regularity of the breathing signals. CBCT projection images from five patients acquired with the Varian Onboard Imager on the Clinac iX System Linear Accelerator (Varian Medical Systems, Palo Alto, CA) were employed to assess the proposed technique. Stable breathing signals can be reliably extracted using the proposed algorithm. Reference waveforms obtained using an air bellows belt (Philips Medical Systems, Cleveland, OH) were exported and compared to those with the AS based signals. The average errors for the enrolled patients between the estimated breath per minute (bpm) and the reference waveform bpm can be as low as  −0.07 with the standard deviation 1.58. The new algorithm outperformed the original AS technique for all patients by 8.5% to 30%. The impact of gantry rotation on the breathing signal was assessed with data acquired with a Quasar phantom (Modus Medical Devices Inc., London, Canada) and found to be minimal on the signal frequency. The new technique developed in this work will provide a practical solution to rendering markerless breathing signal using the CBCT projections for thoracic and abdominal patients. (paper)

  4. Measurement of g factors of excited states in radioactive beams by the transient field technique: 132Te

    International Nuclear Information System (INIS)

    Benczer-Koller, N.; Kumbartzki, G.; Gurdal, G; Gross, Carl J; Krieger, B; Hatarik, Robert; O'Malley, Patrick; Pain, S. D.; Segen, L.; Baktash, Cyrus; Bingham, C. R.; Danchev, M.; Grzywacz, R.; Mazzocchi, C.

    2008-01-01

    The g factor of the 2 1 + state in 52 132 Te, E(2 1 + ) = 0.9739 MeV, r = 2.6 ps, was measured by the transient field technique applied to a radioactive beam. The development of an experimental approach necessary for work in radioactive beam environments is described. The result g = 0.28(15) agrees with the previous measurement by the recoil-in-vacuum technique, but here the sign of the g factor is measured as well

  5. Geometric considerations in magnetron sputtering

    International Nuclear Information System (INIS)

    Thornton, J.A.

    1982-01-01

    The recent development of high performance magnetron type discharge sources has greatly enhaced the range of coating applications where sputtering is a viable deposition process. Magnetron sources can provide high current densities and sputtering rates, even at low pressures. They have much reduced substrate heating rates and can be scaled to large sizes. Magnetron sputter coating apparatuses can have a variety of geometric and plasma configurations. The target geometry affects the emission directions of both the sputtered atoms and the energetic ions which are neutralized and reflected at the cathode. This fact, coupled with the long mean free particle paths which are prevalent at low pressures, can make the coating properties very dependent on the apparatus geometry. This paper reviews the physics of magnetron operation and discusses the influences of apparatus geometry on the use of magnetrons for rf sputtering and reactive sputtering, as well as on the microstructure and internal stresses in sputtered metallic coatings. (author) [pt

  6. Signal processing techniques for lithium beam polarimetry on DIII-D

    International Nuclear Information System (INIS)

    Thomas, D. M.; Leonard, A. W.

    2006-01-01

    On the DIII-D tokamak the LIBEAM diagnostic provides precise measurements of the local magnetic field direction by combined polarimetry/ spectroscopy of the Zeeman-split 2S-2P lithium resonance line. Using these measurements we are able to determine the behavior of the edge toroidal current density j φ (r), a parameter of critical interest for edge stability and performance. For a successful measurement, analysis of the polarization state of the spectrally filtered fluorescence must be done with high precision in the presence of nonideal filtering, beam intensity evolution, and dynamically varying background light. This is accomplished by polarization modulation of the collected emission, followed by digital demodulation at various harmonics of the modulation frequency. Either lock-in or fast Fourier transform techniques can be used to determine the various Stokes parameters and reconstruct the field directions based on accurate spatial and polarization efficiency calibrations. Details of the specific techniques used to analyze various DIII-D discharges are described, along with a discussion of the present limitations and some possible avenues towards improving the analysis

  7. Fabrication of superconducting MgB2 nanostructures by an electron beam lithography-based technique

    Science.gov (United States)

    Portesi, C.; Borini, S.; Amato, G.; Monticone, E.

    2006-03-01

    In this work, we present the results obtained in fabrication and characterization of magnesium diboride nanowires realized by an electron beam lithography (EBL)-based method. For fabricating MgB2 thin films, an all in situ technique has been used, based on the coevaporation of B and Mg by means of an e-gun and a resistive heater, respectively. Since the high temperatures required for the fabrication of good quality MgB2 thin films do not allow the nanostructuring approach based on the lift-off technique, we structured the samples combining EBL, optical lithography, and Ar milling. In this way, reproducible nanowires 1 μm long have been obtained. To illustrate the impact of the MgB2 film processing on its superconducting properties, we measured the temperature dependence of the resistance on a nanowire and compared it to the original magnesium diboride film. The electrical properties of the films are not degraded as a consequence of the nanostructuring process, so that superconducting nanodevices may be obtained by this method.

  8. Fabrication of high-transmission microporous membranes by proton beam writing-based molding technique

    Science.gov (United States)

    Wang, Liping; Meyer, Clemens; Guibert, Edouard; Homsy, Alexandra; Whitlow, Harry J.

    2017-08-01

    Porous membranes are widely used as filters in a broad range of micro and nanofluidic applications, e.g. organelle sorters, permeable cell growth substrates, and plasma filtration. Conventional silicon fabrication approaches are not suitable for microporous membranes due to the low mechanical stability of thin film substrates. Other techniques like ion track etching are limited to the production of randomly distributed and randomly orientated pores with non-uniform pore sizes. In this project, we developed a procedure for fabricating high-transmission microporous membranes by proton beam writing (PBW) with a combination of spin-casting and soft lithography. In this approach, focused 2 MeV protons were used to lithographically write patterns consisting of hexagonal arrays of high-density pillars of few μm size in a SU-8 layer coated on a silicon wafer. After development, the pillars were conformably coated with a thin film of poly-para-xylylene (Parylene)-C release agent and spin-coated with polydimethylsiloxane (PDMS). To facilitate demolding, a special technique based on the use of a laser-cut sealing tape ring was developed. This method facilitated the successful delamination of 20-μm thick PDMS membrane with high-density micropores from the mold without rupture or damage.

  9. Analysis and modification of blue sapphires from Rwanda by ion beam techniques

    Science.gov (United States)

    Bootkul, D.; Chaiwai, C.; Tippawan, U.; Wanthanachaisaeng, B.; Intarasiri, S.

    2015-12-01

    Blue sapphire is categorised in a corundum (Al2O3) group. The gems of this group are always amazed by their beauties and thus having high value. In this study, blue sapphires from Rwanda, recently came to Thai gemstone industry, are chosen for investigations. On one hand, we have applied Particle Induced X-ray Emission (PIXE), which is a highly sensitive and precise analytical technique that can be used to identify and quantify trace elements, for chemical analysis of the sapphires. Here we have found that the major element of blue sapphires from Rwanda is Al with trace elements such as Fe, Ti, Cr, Ga and Mg as are commonly found in normal blue sapphire. On the other hand, we have applied low and medium ion implantations for color improvement of the sapphire. It seems that a high amount of energy transferring during cascade collisions have altered the gems properties. We have clearly seen that the blue color of the sapphires have been intensified after nitrogen ion bombardment. In addition, the gems were also having more transparent and luster. The UV-Vis-NIR measurement detected the modification of their absorption properties, implying of the blue color increasing. Here the mechanism of these modifications is postulated and reported. In any point of view, the bombardment by using nitrogen ion beam is a promising technique for quality improvement of the blue sapphire from Rwanda.

  10. A simple technique for treating age-related macular degeneration with external beam radiotherapy

    International Nuclear Information System (INIS)

    Roos, Daniel E.; Francis, J. Winston; Newnham, W. John

    1999-01-01

    Purpose: To develop a simple external beam photon radiotherapy technique to treat age-related macular degeneration without the need for simulation, planning computed tomography (CT) or computer dosimetry. Methods and Materials: The goal was to enable the treatment to be set up reliably on the treatment machine on Day 1 with the patient supine in a head cast without any prior planning. Using measurements of ocular globe topography from Karlsson et al. (Int J Radiat Oncol Biol Phys 1996; 33: 705-712), we chose a point 1.5 cm behind the anterior surface of the upper eyelid (ASUE) as the isocentre of a half-beam, blocked, 5.0 x 3.0-cm, angled lateral field to treat the involved eye. This would position the isocentre about 0.5 cm behind the posterior surface of the lens, and a little over 1 cm in front of the macula, according to Karlsson et al. The setup requires initial adjustment of the gantry from horizontal (to account for any asymmetry of position of the eyes), then angling 15 deg. posteriorly to avoid the contralateral eye. Finally, the couch is raised to position the isocentre 1.5 cm behind the ASUE. Results: To verify the applicability of the technique, we performed CT and computer dosimetry on the first 11 eyes so treated. Our CT measurements were in good agreement with Karlsson et al. The lens dose was < 5% and the macula was within the 95% isodose curve in each case (6-MV linac). Treatment setup time is approximately 10 min each day. The 11 patients were treated with 5 x 2.00 Gy (2 patients) or 5 x 3.00 Gy (9 patients), and subjective response on follow-up over 1 to 12 months (median 4 months) was comparable to previously reported results, with no significant acute side effects. Conclusion: Our technique is easy to set up and reliably treats the macula, with sparing of the lens and contralateral eye. It enables treatment to commence rapidly and cost-effectively without the need for simulation or CT computer planning

  11. Designed-seamless irradiation technique for extended whole mediastinal proton-beam irradiation for esophageal cancer

    Directory of Open Access Journals (Sweden)

    Okonogi Noriyuki

    2012-10-01

    Full Text Available Abstract Background Proton-beam therapy (PBT provides therapeutic advantages over conformal x-ray therapy in sparing organs at risk when treating esophageal cancer because of the fundamental physical dose distribution of the proton-beam. However, cases with extended esophageal lesions are difficult to treat with conventional PBT with a single isocentric field, as the length of the planning target volume (PTV is longer than the available PBT field size in many facilities. In this study, the feasibility of a practical technique to effectively match PBT fields for esophageal cancer with a larger regional field beyond the available PBT field size was investigated. Methods Twenty esophageal cancer patients with a larger regional field than the available PBT single-field size (15 cm in our facility were analyzed. The PTV was divided into two sections to be covered by a single PBT field. Subsequently, each PTV isocenter was aligned in a cranial-caudal (CC axis to rule out any influence by the movement of the treatment couch in anterior-posterior and left-right directions. To obtain the appropriate dose distributions, a designed-seamless irradiation technique (D-SLIT was proposed. This technique requires the following two adjustments: (A blocking a part of the PTV by multi-leaf collimator(s (MLCs; and (B fine-tuning the isocenter distance by the half-width of the MLC leaf (2.5 mm in our facility. After these steps, the inferior border of the cranial field was designed to match the superior border of the caudal field. Dose distributions along the CC axis around the field junction were evaluated by the treatment-planning system. Dose profiles were validated with imaging plates in all cases. Results The average and standard deviation of minimum dose, maximum dose, and dose range between maximum and minimum doses around the field junction by the treatment-planning system were 95.9 ± 3.2%, 105.3 ± 4.1%, and 9.4 ± 5.2%. The dose profile validated by the

  12. Uniform elemental analysis of materials by sputtering and photoionization mass spectrometry

    International Nuclear Information System (INIS)

    Chun, He; Basler, J.N.; Becker, C.H.

    1997-01-01

    Analysis of the elemental composition of surfaces commonly involves techniques in which atoms or ions are ablated from the material's surface and detected by mass spectrometry. Secondary-ion mass spectrometry is widely used for detection with high sensitivity (down to a few parts per billion) but technical problems prevent it from being truly quantitative. Some of these problems are circumvented by nonresonant laser post-ionization of sputtered atoms followed by time-of-flight mass spectrometry (surface analysis by laser ionization: SALI). But when there are large differences in ionization probabilities amongst different elements in the material, the detection sensitivity can be non-uniform and accurate quantification remains out of reach. Here we report that highly uniform, quantitative and sensitive analysis of materials can be achieved using a high-energy (5-keV) ion beam for sputtering coupled with a very-high-intensity laser to induce multiphoton ionization of the sputtered atoms. We show uniform elemental sensitivity for several samples containing elements with very different ionization potentials, suggesting that this approach can now be regarded as quantitative for essentially any material. (author)

  13. Recent advancements in sputter-type heavy negative ion sources

    International Nuclear Information System (INIS)

    Alton, G.D.

    1989-01-01

    Significant advancement have been made in sputter-type negative ion sources which utilize direct surface ionization, or a plasma to form the positive ion beam used to effect sputtering of samples containing the material of interest. Typically, such sources can be used to generate usable beam intensities of a few μA to several mA from all chemically active elements, depending on the particular source and the electron affinity of the element in question. The presentation will include an introduction to the fundamental processes underlying negative ion formation by sputtering from a low work function surface and several sources will be described which reflect the progress made in this technology. 21 refs., 9 figs., 1 tab

  14. Stress, microstructure and evolution under ion irradiation in thin films grown by ion beam sputtering: modelling and application to interfacial effects in metallic multilayers; Contraintes, microstructure et sollicitation sous irradiation aux ions de films minces elabores par pulverisation ionique: modelisation et application a l'etude des effets interfaciaux dans des multicouches metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Debelle, A

    2006-09-15

    We have investigated the formation of the interfacial chemical mixing in Mo/Ni multilayers, and particularly the influence of ballistic effects during the growth. For this purpose, hetero-epitaxial b.c.c./f.c.c. Mo(110)/Ni(111) multilayers were grown by two deposition methods: thermal evaporation and direct ion beam sputtering. As a preliminary, an accurate description of the stress state in pure sputtered Mo thin films was required. Microstructural and stress state analyses were essentially carried out by X-ray diffraction, and ion irradiation was used as a powerful tool to control the stress level. We showed that thermal evaporated thin films exhibit a weak tensile growth stress ({approx} 0.6 GPa) that can be accounted for by the grain boundary relaxation model, whereas sputtered thin films develop large compressive growth stress (- 2 to - 4 GPa). This latter results from the bombardment of the growing film by the energetic particles involved during the sputtering process (atomic peening phenomenon), which induces the formation of defects in the layers, generating volume distortions. We thus developed a stress model that includes a hydrostatic stress component to account for these volume strains. This model allowed us to determine the 'unstressed and free of defects lattice parameter' a{sub 0}, solely linked to chemical effects. For epitaxial Mo layers, it was possible to separate coherency stress from growth stress due to their distinct kinetic evolution during ion irradiation. Therefore, the stress analysis enabled us to determine the a{sub 0} values in Mo sub-layers of Mo/Ni superlattices. A tendency to the formation of an interfacial alloy is observed independently of the growth conditions, which suggests that thermodynamic forces favour the exchange mechanism. However, the extent of the intermixing effect is clearly enhanced by ballistic effects. (author)

  15. Stress, microstructure and evolution under ion irradiation in thin films grown by ion beam sputtering: modelling and application to interfacial effects in metallic multilayers; Contraintes, microstructure et sollicitation sous irradiation aux ions de films minces elabores par pulverisation ionique: modelisation et application a l'etude des effets interfaciaux dans des multicouches metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Debelle, A

    2006-09-15

    We have investigated the formation of the interfacial chemical mixing in Mo/Ni multilayers, and particularly the influence of ballistic effects during the growth. For this purpose, hetero-epitaxial b.c.c./f.c.c. Mo(110)/Ni(111) multilayers were grown by two deposition methods: thermal evaporation and direct ion beam sputtering. As a preliminary, an accurate description of the stress state in pure sputtered Mo thin films was required. Microstructural and stress state analyses were essentially carried out by X-ray diffraction, and ion irradiation was used as a powerful tool to control the stress level. We showed that thermal evaporated thin films exhibit a weak tensile growth stress ({approx} 0.6 GPa) that can be accounted for by the grain boundary relaxation model, whereas sputtered thin films develop large compressive growth stress (- 2 to - 4 GPa). This latter results from the bombardment of the growing film by the energetic particles involved during the sputtering process (atomic peening phenomenon), which induces the formation of defects in the layers, generating volume distortions. We thus developed a stress model that includes a hydrostatic stress component to account for these volume strains. This model allowed us to determine the 'unstressed and free of defects lattice parameter' a{sub 0}, solely linked to chemical effects. For epitaxial Mo layers, it was possible to separate coherency stress from growth stress due to their distinct kinetic evolution during ion irradiation. Therefore, the stress analysis enabled us to determine the a{sub 0} values in Mo sub-layers of Mo/Ni superlattices. A tendency to the formation of an interfacial alloy is observed independently of the growth conditions, which suggests that thermodynamic forces favour the exchange mechanism. However, the extent of the intermixing effect is clearly enhanced by ballistic effects. (author)

  16. Solid-state electrical conductivity and alcohol sensing properties of radio frequency sputtered thin films of Ti4+ doped eskolaite Cr2O3 derived from citrate combustion technique

    International Nuclear Information System (INIS)

    Pokhrel, Suman; Huo Lihua; Zhao Hui; Gao Shan

    2008-01-01

    Fine powder of Cr 1.8 Ti 0.2 O 3 (CTO) was prepared by citrate combustion technique followed by compacting into discs of 40 mm diameter. Discs were used as radio frequency sputtering targets and coated on a hollow ceramic tube of 4 mm length comprising two Au-electrodes with 4-probe contact and on Al 2 O 3 slices with interdigitated gold electrodes. The films were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and atomic force microscopy techniques. The resistance of the film derived from alternate current impedance measurement in ambient air was found to decrease with increasing temperature. The activation energy was found to be 0.39 eV. These films were exposed to various concentrations of alcohols followed by determination of sensor response, reversibility, potential stability and reproducibility. The sensor response was attributed to the surface catalytic reaction of R-OH with O - (ads) to form adsorbed R-CHO

  17. Bonding techniques for flexural strengthening of R.C. beams using CFRP laminates

    Directory of Open Access Journals (Sweden)

    Alaa Morsy

    2013-09-01

    Full Text Available This paper presents an experimental study of an alternative method of attaching FRP laminates to reinforced concrete beams by the way of fasting steel rivets through the FRP laminate and concrete substrate. Five full scale R.C. beams were casted and strengthened in flexural using FRP laminate bonded with conventional epoxy and compared with other beams strengthened with FRP laminate and bonded with fastener “steel rivets” of 50 mm length and 10 mm diameter. Based on experimental evidence the beam strengthened with conventional bonding methods failed due to de-bonding with about 13% increase over the un-strengthened beam. On the other hand, the beams strengthened with FRP laminate and bonded by four steel fastener rivets only failed by de-bonding also but at higher flexural capacity with increase 19% over the un-strengthened beam.

  18. Electronic sputtering of biomolecules and its application in mass spectrometry

    International Nuclear Information System (INIS)

    Haakansson, P.; Sundqvist, B.U.R.

    1989-01-01

    In 1974 Macfarlane discovered that fast heavy ions from a 252-Cf source can desorb and ionize molecules from a solid surface. The mass of the molecules was determined by time-of-flight technique. It has been shown that the desorption mechanism is associated with the electron part of the stopping power of the primary ion and the name 'electron sputtering' has been adopted for the phenomenon to distinguish it from the well-known sputtering process with ions of KeV energy. A review of electronic sputtering of biomolecules will be given as well as recent measurements on Langmuir-Blodgett films. One important application of electronic sputtering is in the field of mass spectrometry. With this technique large and nonvolatile molecules can be studied. Particularly adsorption of biomolecules to a nitrocellulose backing has proven to be very useful. Examples will be given of mass spectra from peptides with a molecular weight above 20,000 u. (author)

  19. Lung stereotactic body radiotherapy using a coplanar versus a non-coplanar beam technique: a comparison of clinical outcomes

    Science.gov (United States)

    Stauder, Michael C.; Miller, Robert C.; Garces, Yolanda I.; Foote, Robert L.; Sarkaria, Jann N.; Bauer, Heather J.; Mayo, Charles S.; Olivier, Kenneth R.

    2013-01-01

    Objectives To determine if lung stereotactic body radiotherapy (SBRT) using a coplanar beam technique was associated with similar outcomes as lung SBRT using a non-coplanar beam technique. Methods A retrospective review was performed of patients undergoing lung SBRT between January 2008 and April 2011. SBRT was initially delivered with multiple non-coplanar, non-overlapping beams; however, starting in December 2009, SBRT was delivered predominantly with all coplanar beams in order to reduce treatment time and complexity. Results This analysis included 149 patients; the median follow-up was 21 months. SBRT was delivered for primary (n = 90) or recurrent (n = 17) non-small cell lung cancer, or lung oligometastasis (n = 42). The most common dose (Gy)/fraction (fx) regimens were 48 Gy/4 fx (39%), 54 Gy/3 fx (37%), and 50 Gy/5 fx (17%). The beam arrangement was coplanar in 61 patients (41%) and non-coplanar in 88 patients (59%). In patients treated with 54 Gy/3 fx, the mean treatment times per fraction for the coplanar and non-coplanar cohorts were 10 and 14 minutes (p < 0.0001). Kaplan-Meier 2-year estimates of overall survival (OS), progression-free survival, and local control (LC) for the coplanar and non-coplanar cohorts were 65% vs. 56% (p = 0.30), 47% vs. 39% (p = 0.71), and 92% and 92% (p = 0.94), respectively. The 1-year estimates of grade 2-5 pulmonary toxicity for the coplanar and non-coplanar cohorts were 11% and 17%, respectively (p = 0.30). On multivariate analysis, beam arrangement was not significantly associated with OS, LC or pulmonary toxicity. Conclusions Patients treated with lung SBRT using a coplanar technique had similar outcomes as those treated with a non-coplanar technique. PMID:29296365

  20. Advanced Integration Techniques on Broadband Millimeter-Wave Beam Steering for 5G Wireless Networks and Beyond

    NARCIS (Netherlands)

    Cao, Zizheng; Ma, Qian; Smolders, Bart; Jiao, Yuqing; Wale, Mike; Oh, Joanne; wu, hequan; Koonen, Ton

    2015-01-01

    Recently, the desired very high throughput of 5G wireless networks drives millimeter-wave (mm-wave) communication into practical applications. A phased array technique is required to increase the effective antenna aperture at mm-wave frequency. Integrated solutions of beamforming/beam steering are

  1. Cure and mechanical behaviors of cycloaliphatic/DGEBA epoxy blend system using electron-beam technique

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.R.; Heo, G.Y.; Park, S.J. [Korea Research Institute of Chemical Technology, Taejeon (Korea)

    2002-05-01

    4-Vinyl-1- cyclohexene diepoxide (VCE)/ diglycidyl ether of bisphenol -A(DGEBA) epoxy blends with benzylquinoxalinium hexafluoroanti-monate were cured using an electron-beam technique. the effect of DGEBA content to VCE on cure behavior, thermal stabilities, and mechanical properties was investigated. The composition of VCE/DGEBA blend system varied within 100:0, 80:20, 60:40. 40:60 20:80, and 0:100wt%. The cure behavior and thermal stability of the cured specimens was monited by near-infrared spectroscopy and thermogravimetric analysis, respectively. Also, the critical stress intensity factor (K{sub 1C}) test of the cured specimens was performed to study the mechanical interfacial properties. As a result, the decreases of short side-chide structure and chain scission were observed in NIR measurements as the DGEBA content increases, resulting in varying the hydroxyl and carbonyl groups. And, the initial decomposition temperature (IDT), temperature of maximum weight loss (T{sub max}), and decomposition activation energy (E{sub d}) as thermal stability factors were increased with increasing the DGEBA content. These results could be explained by mean of decreasing viscosity, stable aromatic ring structure, and grafted interpenetrating polymer network with increasing of DGEBA content. Also, the maximum K{sub 1C} value showed at mixing ratio of 40:60 wt% in this blend system. (author). 22 refs., 2 tabs., 6 figs.

  2. Characterization of ITO/CdO/glass thin films evaporated by electron beam technique

    Directory of Open Access Journals (Sweden)

    Hussein Abdel-Hafez Mohamed and Hazem Mahmoud Ali

    2008-01-01

    Full Text Available A thin buffer layer of cadmium oxide (CdO was used to enhance the optical and electrical properties of indium tin oxide (ITO films prepared by an electron-beam evaporation technique. The effects of the thickness and heat treatment of the CdO layer on the structural, optical and electrical properties of ITO films were carried out. It was found that the CdO layer with a thickness of 25 nm results in an optimum transmittance of 70% in the visible region and an optimum resistivity of 5.1×10−3 Ω cm at room temperature. The effect of heat treatment on the CdO buffer layer with a thickness of 25 nm was considered to improve the optoelectronic properties of the formed ITO films. With increasing annealing temperature, the crystallinity of ITO films seemed to improve, enhancing some physical properties, such as film transmittance and conductivity. ITO films deposited onto a CdO buffer layer heated at 450 °C showed a maximum transmittance of 91% in the visible and near-infrared regions of the spectrum associated with the highest optical energy gap of 3.61 eV and electrical resistivity of 4.45×10−4 Ω cm at room temperature. Other optical parameters, such as refractive index, extinction coefficient, dielectric constant, dispersion energy, single effective oscillator energy, packing density and free carrier concentration, were also studied.

  3. Transparent conducting ZnO-CdO thin films deposited by e-beam evaporation technique

    Science.gov (United States)

    Mohamed, H. A.; Ali, H. M.; Mohamed, S. H.; Abd El-Raheem, M. M.

    2006-04-01

    Thin films of Zn{1-x} Cd{x}O with x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 at.% were deposited by electron-beam evaporation technique. It has been found that, for as-deposited films, both the transmittance and electrical resistivity decreased with increasing the Cd content. To improve the optical and electrical properties of these films, the effect of annealing temperature and time were taken into consideration for Zn{1-x} Cd{x}O film with x = 0.2. It was found that, the optical transmittance and the electrical conductivity were improved significantly with increasing the time of annealing. At fixed temperature of 300 °C, the transmittance increased with increasing the time of annealing and reached its maximum values of 81% in the visible region and 94% in the NIR region at annealing time of 120 min. The low electrical resistivity of 3.6 × 10-3 Ω cm was achieved at the same conditions. Other parameters named free carrier concentrations, refractive index, extinction coefficient, plasma frequency, and relaxation time were studied as a function of annealing temperature and time for 20% Cd content.

  4. Optical and Electrical Properties of Tin-Doped Cadmium Oxide Films Prepared by Electron Beam Technique

    Science.gov (United States)

    Ali, H. M.; Mohamed, H. A.; Wakkad, M. M.; Hasaneen, M. F.

    2009-04-01

    Tin-doped cadmium oxide films were deposited by electron beam evaporation technique. The structural, optical and electrical properties of the films were characterized. The X-ray diffraction (XRD) study reveals that the films are polycrystalline in nature. As composition and structure change due to the dopant ratio and annealing temperature, the carrier concentration was varied around 1020 cm-3, and the mobility increased from less than 10 to 45 cm2 V-1 s-1. A transmittance value of ˜83% and a resistivity value of 4.4 ×10-4 Ω cm were achieved for (CdO)0.88(SnO2)0.12 film annealed at 350 °C for 15 min., whereas the maximum value of transmittance ˜93% and a resistivity value of 2.4 ×10-3 Ω cm were obtained at 350 °C for 30 min. The films exhibited direct band-to-band transitions, which corresponded to optical band gaps of 3.1-3.3 eV.

  5. Fault Diagnosis of Beam-Like Structure Using Modified Fuzzy Technique

    Directory of Open Access Journals (Sweden)

    Dhirendranath Thatoi

    2014-01-01

    Full Text Available This paper presents a novel hybrid fuzzy logic based artificial intelligence (AI technique applicable to diagnosis of the crack parameters in a fixed-fixed beam by using the vibration signatures as input. The presence of damage in engineering structures leads to changes in vibration signatures like natural frequency and mode shapes. In the first part of this work, a structure with a failure crack has been analyzed using finite element method (FEM and retrospective changes in the vibration signatures have been recorded. In the second part of the research work, these deviations in the vibration signatures for the first three mode shapes have been taken as input parameters for a fuzzy logic based controller for calculation of crack location and its severity as output parameters. In the proposed fuzzy controller, hybrid membership functions have been taken. Several fuzzy rules have been identified for prediction of crack depth and location and the results have been compared with finite element analysis. A database of experimental results has also been considered to check the robustness of the fuzzy controller. The results show that predictions for the nondimensional crack location, α, deviate ~2.4% from experimental values and for the nondimensional crack depth, δ, are less than ~−2%.

  6. Microstructure and surface morphology of YSZ thin films deposited by e-beam technique

    International Nuclear Information System (INIS)

    Laukaitis, G.; Dudonis, J.; Milcius, D.

    2008-01-01

    In present study yttrium-stabilized zirconia (YSZ) thin films were deposited on optical quartz (amorphous SiO 2 ), porous Ni-YSZ and crystalline Alloy 600 (Fe-Ni-Cr) substrates using e-beam deposition technique and controlling technological parameters: substrate temperature and electron gun power which influence thin-film deposition mechanism. X-ray diffraction, scanning electron microscopy (SEM), and atomic force microscopy (AFM) were used to investigate how thin-film structure and surface morphology depend on these parameters. It was found that the crystallite size, roughness and growth mechanism of YSZ thin films are influenced by electron gun power. To clarify the experimental results, YSZ thin-film formation as well evolution of surface roughness at its initial growing stages were analyzed. The evolution of surface roughness could be explained by the processes of surface mobility of adatoms and coalescence of islands. The analysis of these experimental results explain that surface roughness dependence on substrate temperature and electron gun power non-monotonous which could result from diffusivity of adatoms and the amount of atomic clusters in the gas stream of evaporated material

  7. Improved Understanding of Implosion Symmetry through New Experimental Techniques Connecting Hohlraum Dynamics with Laser Beam Deposition

    Science.gov (United States)

    Ralph, Joseph; Salmonson, Jay; Dewald, Eduard; Bachmann, Benjamin; Edwards, John; Graziani, Frank; Hurricane, Omar; Landen, Otto; Ma, Tammy; Masse, Laurent; MacLaren, Stephen; Meezan, Nathan; Moody, John; Parrilla, Nicholas; Pino, Jesse; Sacks, Ryan; Tipton, Robert

    2017-10-01

    Understanding what affects implosion symmetry has been a challenge for scientists designing indirect drive inertial confinement fusion experiments on the National Ignition Facility (NIF). New experimental techniques and data analysis have been employed aimed at improving our understanding of the relationship between hohlraum dynamics and implosion symmetry. Thin wall imaging data allows for time-resolved imaging of 10 keV Au l-band x-rays providing for the first time on the NIF, a spatially resolved measurement of laser deposition with time. In the work described here, we combine measurements from the thin wall imaging with time resolved views of the interior of the hohlraum. The measurements presented are compared to hydrodynamic simulations as well as simplified physics models. The goal of this work is to form a physical picture that better explains the relationship of the hohlraum dynamics and capsule ablator on laser beam propagation and implosion symmetry. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

  8. Augmenting the bioactivity of polyetheretherketone using a novel accelerated neutral atom beam technique.

    Science.gov (United States)

    Ajami, S; Coathup, M J; Khoury, J; Blunn, G W

    2017-08-01

    Polyetheretherketone (PEEK) is an alternative to metallic implants in orthopedic applications; however, PEEK is bioinert and does not osteointegrate. In this study, an accelerated neutral atom beam technique (ANAB) was employed to improve the bioactivity of PEEK. The aim was to investigate the growth of human mesenchymal stem cells (hMSCs), human osteoblasts (hOB), and skin fibroblasts (BR3G) on PEEK and ANAB PEEK. The surface roughness and contact angle of PEEK and ANAB PEEK was measured. Cell metabolic activity, proliferation and alkaline phosphatase (ALP) was measured and cell attachment was determined by quantifying adhesion plaques with cells. ANAB treatment increased the surface hydrophilicity [91.74 ± 4.80° (PEEK) vs. 74.82 ± 2.70° (ANAB PEEK), p PEEK compared to PEEK (p PEEK surfaces. MSCs seeded on ANAB PEEK in the presence of osteogenic media, expressed increased levels of ALP compared to untreated PEEK (p PEEK. ANAB treatment may improve the osteointegration of PEEK implants. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1438-1446, 2017. © 2016 Wiley Periodicals, Inc.

  9. Optical techniques for electron-beam characterizations on the APS SASE FEL project

    International Nuclear Information System (INIS)

    Lumpkin, A.H.; Yang, B.X.; Berg, W.J.; White, M.; Lewellen, J.W.; Milton, S.V.

    1998-01-01

    At the Advanced Photon Source (APS) the injector linac's DC thermionic gun is being supplemented by a low-emittance rf thermionic gun that will support the SASE FEL project. To address the anticipated smaller beam sizes, the standard Chromox beam-profiling screens are being complemented by optical transition radiation (OTR) and Ce-doped YAG single-crystal converters. Direct comparisons of the effective conversion efficiency, spatial resolution, and time response of the three converter screen types have been performed using the DC thermionic gun's beam accelerated to 400 to 650 MeV. An apparent blurring of observed beam size with increasing incident charge areal density in the YAG crystal was observed for the first time. Only the OTR was prompt enough for the few-ps domain micropulse bunch length measurements performed with a stream camera. Initial beam images of the rf-thermionic gun beam have also been obtained

  10. Reactive dual magnetron sputtering for large area application

    International Nuclear Information System (INIS)

    Struempfel, J.

    2002-01-01

    Production lines for large area coating demand high productivity of reactive magnetron sputtering processes. Increased dynamic deposition rates for oxides and nitrides were already obtained by using of highly powered magnetrons in combination with advanced sputter techniques. However, besides high deposition rates the uniformity of such coatings has to be carefully considered. First the basics of reactive sputtering processes and dual magnetron sputtering are summarized. Different methods for process stabilization and control are commonly used for reactive sputtering. The Plasma Emission Monitor (PE M) offers the prerequisite for fast acting process control derived from the in-situ intensity measurements of a spectral line of the sputtered target material. Combined by multiple Plasma Emission Monitor control loops segmented gas manifolds are able to provide excellent thin film uniformity at high deposition rates. The Dual Magnetron allows a broad range of processing by different power supply modes. Medium frequency, DC and pulsed DC power supplies can be used for high quality layers. Whereas the large area coating of highly isolating layers like TiO 2 or SiO 2 is dominated by MF sputtering best results for coating with transparent conductive oxides are obtained by dual DC powering of the dual magnetron arrangement. (Author)

  11. Fluence-dependent sputtering yield of micro-architectured materials

    Energy Technology Data Exchange (ETDEWEB)

    Matthes, Christopher S.R.; Ghoniem, Nasr M., E-mail: ghoniem@ucla.edu; Li, Gary Z.; Matlock, Taylor S.; Goebel, Dan M.; Dodson, Chris A.; Wirz, Richard E.

    2017-06-15

    Highlights: • Sputtering yield is shown to be transient and heavily dependent on surface architecture. • Fabricated nano- and Microstructures cause geometric re-trapping of sputtered material, which leads to a self-healing mechanism. • Initially, the sputtering yield of micro-architectured Mo is approximately 1/2 the value as that of a planar surface. • The study demonstrates that the sputtering yield is a dynamic property, dependent on the surface structure of a material. • A developed phenomenological model mathematically describes the transient behavior of the sputtering yield as a function of plasma fluence. - Abstract: We present an experimental examination of the relationship between the surface morphology of Mo and its instantaneous sputtering rate as function of low-energy plasma ion fluence. We quantify the dynamic evolution of nano/micro features of surfaces with built-in architecture, and the corresponding variation in the sputtering yield. Ballistic deposition of sputtered atoms as a result of geometric re-trapping is observed, and re-growth of surface layers is confirmed. This provides a self-healing mechanism of micro-architectured surfaces during plasma exposure. A variety of material characterization techniques are used to show that the sputtering yield is not a fundamental property, but that it is quantitatively related to the initial surface architecture and to its subsequent evolution. The sputtering yield of textured molybdenum samples exposed to 300 eV Ar plasma is roughly 1/2 of the corresponding value for flat samples, and increases with ion fluence. Mo samples exhibited a sputtering yield initially as low as 0.22 ± 5%, converging to 0.4 ± 5% at high fluence. The sputtering yield exhibits a transient behavior as function of the integrated ion fluence, reaching a steady-state value that is independent of initial surface conditions. A phenomenological model is proposed to explain the observed transient sputtering phenomenon, and to

  12. Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique

    Energy Technology Data Exchange (ETDEWEB)

    Halavanau, A. [Northern Illinois U.; Qiang, G. [Tsinghua U., Beijing, Dept. Eng. Phys.; Ha, G. [POSTECH; Wisniewski, E. [Argonne (main); Piot, P. [NIU, DeKalb; Power, J. G. [Argonne (main); Gai, W. [Argonne (main)

    2017-07-24

    A common issue encountered in photoemission electron sources used in electron accelerators is the transverse inhomogeneity of the laser distribution resulting from the laser-amplification process and often use of frequency up conversion in nonlinear crystals. A inhomogeneous laser distribution on the photocathode produces charged beams with lower beam quality. In this paper, we explore the possible use of microlens arrays (fly-eye light condensers) to dramatically improve the transverse uniformity of the drive laser pulse on UV photocathodes. We also demonstrate the use of such microlens arrays to generate transversely-modulated electron beams and present a possible application to diagnose the properties of a magnetized beam.

  13. Production of Hydrated Metal Ions by Fast Ion or Atom Beam Sputtering. Collision-Induced Dissociation and Successive Hydration Energies of Gaseous Cu+ with 1-4 Water Molecules

    NARCIS (Netherlands)

    Magnera, Thomas F.; David, Donald E.; Stulik, Dusan; Orth, Robert G.; Jonkman, Harry T.; Michl, Josef

    1989-01-01

    Low-temperature sputtering of frozen aqueous solutions of metal salts, of hydrated crystalline transition-metal salts, of frosted metal surfaces, and of frosted metal salts with kiloelectronvolt energy rare gas atoms or ions produces copious amounts of cluster ions, among which M+(H2O)n and/or

  14. Secondary ion formation during electronic and nuclear sputtering of germanium

    Science.gov (United States)

    Breuer, L.; Ernst, P.; Herder, M.; Meinerzhagen, F.; Bender, M.; Severin, D.; Wucher, A.

    2018-06-01

    Using a time-of-flight mass spectrometer attached to the UNILAC beamline located at the GSI Helmholtz Centre for Heavy Ion Research, we investigate the formation of secondary ions sputtered from a germanium surface under irradiation by swift heavy ions (SHI) such as 5 MeV/u Au by simultaneously recording the mass spectra of the ejected secondary ions and their neutral counterparts. In these experiments, the sputtered neutral material is post-ionized via single photon absorption from a pulsed, intensive VUV laser. After post-ionization, the instrument cannot distinguish between secondary ions and post-ionized neutrals, so that both signals can be directly compared in order to investigate the ionization probability of different sputtered species. In order to facilitate an in-situ comparison with typical nuclear sputtering conditions, the system is also equipped with a conventional rare gas ion source delivering a 5 keV argon ion beam. For a dynamically sputter cleaned surface, it is found that the ionization probability of Ge atoms and Gen clusters ejected under electronic sputtering conditions is by more than an order of magnitude higher than that measured for keV sputtered particles. In addition, the mass spectra obtained under SHI irradiation show prominent signals of GenOm clusters, which are predominantly detected as positive or negative secondary ions. From the m-distribution for a given Ge nuclearity n, one can deduce that the sputtered material must originate from a germanium oxide matrix with approximate GeO stoichiometry, probably due to residual native oxide patches even at the dynamically cleaned surface. The results clearly demonstrate a fundamental difference between the ejection and ionization mechanisms in both cases, which is interpreted in terms of corresponding model calculations.

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

    International Nuclear Information System (INIS)

    Olivero, P.; Manfredotti, C.; 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 quantitative study of the inhomogeneity of the charge transport parameter defined as the product of mobility and lifetime for both electron and holes. XBIL represents a technique complementary to ion beam induced luminescence (IBIL), which has already been used by our group, since X-ray energy loss profile in the material is different from that of MeV ions. X-ray induced luminescence maps have been performed simultaneously with induced photocurrent maps, to correlate charge transport and induced luminescence properties of diamond. Simultaneous XBICC and XBIL maps exhibit features of partial complementarity that have been interpreted on the basis of considerations on radiative and non-radiative recombination processes which compete with charge transport efficiency

  16. Dosimetric characterization of BeO samples in alpha, beta and X radiation beams using luminescent techniques

    International Nuclear Information System (INIS)

    Groppo, Daniela Piai

    2013-01-01

    In the medical field, the ionizing radiation is used both for therapeutic and diagnostic purposes, in a wide range of radiation doses. In order to ensure that the objective is achieved in practice, detailed studies of detectors and devices in different types of radiations beams are necessary. In this work a dosimetric characterization of BeO samples was performed using the techniques of thermoluminescence (TL) and optically stimulated luminescence (OSL) by a comparison of their response for alpha, beta and X radiations and the establishment of an appropriated system for use in monitoring of these radiations beams. The main results are: the high sensitivity to beta radiation for both techniques, good reproducibility of TL and OSL response (coefficients of variation lower than 5%), maximum energy dependence of the X radiation of 28% for the TL technique, and only 7% for the OSL technique, within the studied energy range. The dosimetric characteristics obtained in this work show the possibility of applying BeO samples to dosimetry of alpha, beta and X radiations, considering the studied dose ranges, using the TL and OSL techniques. From the results obtained, the samples of BeO showed their potential use for beam dosimetry in diagnostic radiology and radiotherapy. (author)

  17. Progress in ETA-II magnetic field alignment using stretched wire and low energy electron beam techniques

    International Nuclear Information System (INIS)

    Griffith, L.V.; Deadrick, F.J.

    1991-01-01

    Flux line alignment of the solenoidal focus magnets used on the ETA-II linear induction accelerator is a key element leading to a reduction of beam corkscrew motion. Two techniques have been used on the ETA-II accelerator to measure and establish magnet alignment. A low energy electron beam has been used to directly map magnetic field lines, and recent work has utilized a pulsed stretched wire technique to measure magnet tilts and offsets with respect to a reference axis. This paper reports on the techniques used in the ETA-II accelerator alignment, and presents results from those measurements which show that accelerator is magnetically aligned to within ∼ ± 200 microns

  18. Pulsed dc self-sustained magnetron sputtering

    International Nuclear Information System (INIS)

    Wiatrowski, A.; Posadowski, W. M.; Radzimski, Z. J.

    2008-01-01

    The magnetron sputtering has become one of the commonly used techniques for industrial deposition of thin films and coatings due to its simplicity and reliability. At standard magnetron sputtering conditions (argon pressure of ∼0.5 Pa) inert gas particles (necessary to sustain discharge) are often entrapped in the deposited films. Inert gas contamination can be eliminated during the self-sustained magnetron sputtering (SSS) process, where the presence of the inert gas is not a necessary requirement. Moreover the SSS process that is possible due to the high degree of ionization of the sputtered material also gives a unique condition during the transport of sputtered particles to the substrate. So far it has been shown that the self-sustained mode of magnetron operation can be obtained using dc powering (dc-SSS) only. The main disadvantage of the dc-SSS process is its instability related to random arc formation. In such case the discharge has to be temporarily extinguished to prevent damaging both the magnetron source and power supply. The authors postulate that pulsed powering could protect the SSS process against arcs, similarly to reactive pulsed magnetron deposition processes of insulating thin films. To put this concept into practice, (i) the high enough plasma density has to be achieved and (ii) the type of pulsed powering has to be chosen taking plasma dynamics into account. In this article results of pulsed dc self-sustained magnetron sputtering (pulsed dc-SSS) are presented. The planar magnetron equipped with a 50 mm diameter and 6 mm thick copper target was used during the experiments. The maximum target power was about 11 kW, which corresponded to the target power density of ∼560 W/cm 2 . The magnetron operation was investigated as a function of pulse frequency (20-100 kHz) and pulse duty factor (50%-90%). The discharge (argon) extinction pressure level was determined for these conditions. The plasma emission spectra (400-410 nm range) and deposition

  19. Study of the light emission from hydrogen atoms excited by the beam-foil technique

    International Nuclear Information System (INIS)

    Broll, Norbert.

    1976-01-01

    Zero-field and Stark-induced quantum beat measurements have been performed for beam foil excited hydrogen (H + and H 2 + beam). Experimental evidence of coherent excitation of S and P states of Lyman α line has been demonstrated [fr

  20. An intense lithium ion beam source using vacuum baking and discharge cleaning techniques

    International Nuclear Information System (INIS)

    Moschella, J.J.; Kusse, B.R.; Longfellow, J.P.; Olson, J.C.

    1991-01-01

    We have developed a high-purity, intense, lithium ion beam source which operates at 500 kV and 120 A/cm 2 with pulse widths of 125 ns full width half maximum. The beams were generated using a lithium chloride anode in planar magnetically insulated geometry. We have found that the combination of vacuum baking of the anode at 250 degree C followed by the application of 100 W of pure argon, steady-state, glow discharge cleaning reduced the impurity concentration in the beam to approximately 10% (components other than chlorine or lithium were considered impurities). Although the impurities were low, the concentration of chlorine in the 1+ and 2+ charge states was significant (∼25%). The remaining 65% of the beam consisted of Li + ions. Without the special cleaning process, over half the beam particles were impurities. It was determined that these impurities entered the beam at the anode surface but came originally from material in the vacuum chamber. After the cleaning process, recontamination was observed to occur in approximately 6 min. This long recontamination time, which was much greater than the expected monolayer formation time, was attributed to the elevated temperature of the anode. We also compared the electrical characteristics of the beams produced by LiCl anodes to those generated by a standard polyethylene proton source. In contrast to the polyethylene anode, the LiCl source exhibited a higher impedance, produced beams of lower ion current efficiency and had longer turn on times

  1. Five second helium neutral beam injection using argon-frost cryopumping techniques

    International Nuclear Information System (INIS)

    Phillips, J.C.; Kellman, D.H.; Hong, R.; Kim, J.; Laughon, G.M.

    1995-01-01

    High power helium neutral beams for the heating of tokamak discharges can now be provided for 5 s by using argon cryopumping (of the helium gas) in the beamlines. The DIII-D neutral beam system has routinely provided up to 20 MW of deuterium neutral beam heating in support of experiments on the DIII-D tokamak. Operation of neutral beams with helium has historically presented a problem in that pulse lengths have been limited to 500 ms due to reliance solely on volume pumping of the helium gas. Helium is not condensed on the cryopanels. A system has now been installed to deposit a layer of argon frost on the DIII-D neutral beam cryopanels, between tokamak injection pulses. The layer serves to trap helium on the cryopanels providing sufficient pumping speed for 5 s helium beam extraction. The argon frosting hardware is now present on two of four DIII-D neutral beamlines, allowing injection of up to 6 MW of helium neutral beams per discharge, with pulse lengths of up to 5 s. The argon frosting system is described, along with experimental results demonstrating its effectiveness as a method of economically extending the capabilities of cryogenic pumping panels to allow multi-second helium neutral beam injection

  2. Five second helium neutral beam injection using argon-frost cryopumping techniques

    International Nuclear Information System (INIS)

    Phillips, J.C.; Kellman, D.H.; Hong, R.; Kim, J.; Laughon, G.M.

    1995-10-01

    High power helium neutral beams for the heating of tokamak discharges can now be provided for 5 s by using argon cryopumping (of the helium gas) in the beamlines. A system has now been installed to deposit a layer of argon frost on the DIII-D neutral beam cryopanels, between tokamak injection pulses. The layer serves to trap helium on the cryopanels providing sufficient pumping speed for 5 s helium beam extraction. The argon frosting hardware is now present on two of four DIII-D neutral beamlines, allowing injection of up to 6 MW of helium neutral beams per discharge, with pulse lengths of up to 5 s. The argon frosting system is described, along with experimental results demonstrating its effectiveness as a method of economically extending the capabilities of cryogenic pumping panels to allow multi-second helium neutral beam injection

  3. Deposition and characterization of titania-silica optical multilayers by asymmetric bipolar pulsed dc sputtering of oxide targets

    Energy Technology Data Exchange (ETDEWEB)

    Sagdeo, P R; Shinde, D D; Misal, J S [Optics and Thin Film Laboratory, Autonagar, BARC-Vizag, Visakhapatnam -530012 (India); Kamble, N M; Tokas, R B; Biswas, A; Poswal, A K; Thakur, S; Bhattacharyya, D; Sahoo, N K; Sabharwal, S C, E-mail: nksahoo@barc.gov.i, E-mail: sahoonk@gmail.co [Spectroscopy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2010-02-03

    Titania-silica (TiO{sub 2}/SiO{sub 2}) optical multilayer structures have been conventionally deposited by reactive sputtering of metallic targets. In order to overcome the problems of arcing, target poisoning and low deposition rates encountered there, the application of oxide targets was investigated in this work with asymmetric bipolar pulsed dc magnetron sputtering. In order to evaluate the usefulness of this deposition methodology, an electric field optimized Fabry Perot mirror for He-Cd laser ({lambda} = 441.6 nm) spectroscopy was deposited and characterized. For comparison, this mirror was also deposited by the reactive electron beam (EB) evaporation technique. The mirrors developed by the two complementary techniques were investigated for their microstructural and optical reflection properties invoking atomic force microscopy, ellipsometry, grazing incidence reflectometry and spectrophotometry. From these measurements the layer geometry, optical constants, mass density, topography, surface and interface roughness and disorder parameters were evaluated. The microstructural properties and spectral functional characteristics of the pulsed dc sputtered multilayer mirror were found to be distinctively superior to the EB deposited mirror. The knowledge gathered during this study has been utilized to develop a 21-layer high-pass edge filter for radio photoluminescence dosimetry.

  4. Deposition and characterization of titania-silica optical multilayers by asymmetric bipolar pulsed dc sputtering of oxide targets

    International Nuclear Information System (INIS)

    Sagdeo, P R; Shinde, D D; Misal, J S; Kamble, N M; Tokas, R B; Biswas, A; Poswal, A K; Thakur, S; Bhattacharyya, D; Sahoo, N K; Sabharwal, S C

    2010-01-01

    Titania-silica (TiO 2 /SiO 2 ) optical multilayer structures have been conventionally deposited by reactive sputtering of metallic targets. In order to overcome the problems of arcing, target poisoning and low deposition rates encountered there, the application of oxide targets was investigated in this work with asymmetric bipolar pulsed dc magnetron sputtering. In order to evaluate the usefulness of this deposition methodology, an electric field optimized Fabry Perot mirror for He-Cd laser (λ = 441.6 nm) spectroscopy was deposited and characterized. For comparison, this mirror was also deposited by the reactive electron beam (EB) evaporation technique. The mirrors developed by the two complementary techniques were investigated for their microstructural and optical reflection properties invoking atomic force microscopy, ellipsometry, grazing incidence reflectometry and spectrophotometry. From these measurements the layer geometry, optical constants, mass density, topography, surface and interface roughness and disorder parameters were evaluated. The microstructural properties and spectral functional characteristics of the pulsed dc sputtered multilayer mirror were found to be distinctively superior to the EB deposited mirror. The knowledge gathered during this study has been utilized to develop a 21-layer high-pass edge filter for radio photoluminescence dosimetry.

  5. Depth of origin of sputtered atoms: Experimental and theoretical study of Cu/Ru(0001)

    International Nuclear Information System (INIS)

    Burnett, J.W.; Biersack, J.P.; Gruen, D.M.; Joergensen, B.; Krauss, A.R.; Pellin, M.J.; Schweitzer, E.L.; Yates, J.T. Jr.; Young, C.E.

    1987-01-01

    The depth of origin of sputtered atoms is a subject of considerable interest. The surface sensitivity of analytical techniques such as Secondary Ion Mass Spectrometry (SIMS) and Surface Analysis by Resonance Ionization of Sputtered Atoms (SARISA), and the sputtering properties of strongly segregating alloy systems, are critically dependent on the sputtering depth of origin. A significant discrepancy exists between the predictions of the Sigmund theory and computer sputtering models; in general, the computer models predict a much shallower depth of origin. The existing experimental evidence suggests that most of the sputtered atoms originate in the topmost atomic layer, but until recently, the results have not been definitive. We have experimentally determined the depth of origin of atoms sputtered from surfaces consisting of Cu films of less than two monolayers on a Ru(0001) substrate. The Cu/Ru target was statically sputtered using 3.6 keV Ar + . The sputtered neutrals were non-resonantly laser ionized and detected using SARISA. The Cu/Ru sputtering yield ratio and the suppression of the Ru sputtering yield were determined for various Cu coverages. The results indicate that the majority of the sputtered atoms originate in the topmost atomic layer. The Cu/Ru system is also modeled using a modified Transport of Ions in Matter (TRIM) code. It was found that TRIM C does not correctly treat the first atomic layer, resulting in a serious underestimate of the number of sputtered atoms which originate in this layer. The corrected version adequately describes the results, predicting that for the experimental conditions roughly two-thirds of the sputtered atoms originate in the first atomic layer. These results are significantly greater than the Sigmund theory estimate of >40%. 26 refs., 3 figs., 1 tab

  6. Theory of thermal sputtering

    International Nuclear Information System (INIS)

    Kelly, R.

    1977-01-01

    An energetic ion which is incident on a solid target causes a momentary temperature increase in the impact region, i.e., a so-called thermal spike occurs. Such spikes are capable of causing (or supplementing) disordering, precipitation, crystallization, electronic excitation, stoichiometry change, desorption, and sputtering, it being the contribution to sputtering that is considered here. The approach used is compatible with modern damage-distribution theory. Thus the temperature profile left by the incident ion is taken as a three-dimensional Gaussian with parameters appropriate to power-law scattering, and is used as the initial condition for solving the heat-conduction equation. Let us write this solution as T = T(t, y), where t is time and y is a dimension parallel to the target surface. The vaporization flux from a solid surface is taken as pnsup(1/2)(2π 2 >kT)sup(-1/2), where p, the equilibrium pressure of a vapor species containing n atoms, can be written as p 0 exp(-L/T), p 0 and L are constants largely independent of temperature, and 2 > is the mean mass per atom of target. An equation for the thermal sputtering coefficient is given: after integration the final result takes the form: Ssub(thermal)=pnsup(1/2)[2π 2 >k(Tsub(infinity)+cΔT 0 )]sup(-1/2)πlambda 2 tsub(eff.)atoms/ion, where Tsub(infinity) is the macroscopic target temperature, cΔT 0 is the maximum temperature increase at x = y = 0, p is to be evaluated at T = Tsub(infinity) + cΔT 0 , lambda is the mean atomic spacing of the target, and tsub(eff.) is a quantity with units of time. (author)

  7. Development of Focused Ion Beam technique for high speed steel 3D-SEM artefact fabrication

    DEFF Research Database (Denmark)

    Carli, Lorenzo; MacDonald, A. Nicole; De Chiffre, Leonardo

    2009-01-01

    The work describes preliminary manufacture by grinding, followed by machining on a Focused Ion Beam (FIB), of a high speed steel step artefact for 3D-SEM calibration. The FIB is coupled with a SEM in the so called dual beam instrument. The milling capabilities of FIB were checked from a qualitative...... point of view, using the dual beam SEM imaging, and quantitatively using a reference stylus instrument, to establish traceability. A triangular section having a depth of about 10 μm was machined, where the 50 μm curvature radius due to grinding was reduced to about 2 μm by FIB milling...

  8. Monte Carlo simulation for scanning technique with scattering foil free electron beam: A proof of concept study.

    Directory of Open Access Journals (Sweden)

    Wonmo Sung

    Full Text Available This study investigated the potential of a newly proposed scattering foil free (SFF electron beam scanning technique for the treatment of skin cancer on the irregular patient surfaces using Monte Carlo (MC simulation. After benchmarking of the MC simulations, we removed the scattering foil to generate SFF electron beams. Cylindrical and spherical phantoms with 1 cm boluses were generated and the target volume was defined from the surface to 5 mm depth. The SFF scanning technique with 6 MeV electrons was simulated using those phantoms. For comparison, volumetric modulated arc therapy (VMAT plans were also generated with two full arcs and 6 MV photon beams. When the scanning resolution resulted in a larger separation between beams than the field size, the plan qualities were worsened. In the cylindrical phantom with a radius of 10 cm, the conformity indices, homogeneity indices and body mean doses of the SFF plans (scanning resolution = 1° vs. VMAT plans were 1.04 vs. 1.54, 1.10 vs. 1.12 and 5 Gy vs. 14 Gy, respectively. Those of the spherical phantom were 1.04 vs. 1.83, 1.08 vs. 1.09 and 7 Gy vs. 26 Gy, respectively. The proposed SFF plans showed superior dose distributions compared to the VMAT plans.

  9. Monte Carlo simulation for scanning technique with scattering foil free electron beam: A proof of concept study.

    Science.gov (United States)

    Sung, Wonmo; Park, Jong In; Kim, Jung-In; Carlson, Joel; Ye, Sung-Joon; Park, Jong Min

    2017-01-01

    This study investigated the potential of a newly proposed scattering foil free (SFF) electron beam scanning technique for the treatment of skin cancer on the irregular patient surfaces using Monte Carlo (MC) simulation. After benchmarking of the MC simulations, we removed the scattering foil to generate SFF electron beams. Cylindrical and spherical phantoms with 1 cm boluses were generated and the target volume was defined from the surface to 5 mm depth. The SFF scanning technique with 6 MeV electrons was simulated using those phantoms. For comparison, volumetric modulated arc therapy (VMAT) plans were also generated with two full arcs and 6 MV photon beams. When the scanning resolution resulted in a larger separation between beams than the field size, the plan qualities were worsened. In the cylindrical phantom with a radius of 10 cm, the conformity indices, homogeneity indices and body mean doses of the SFF plans (scanning resolution = 1°) vs. VMAT plans were 1.04 vs. 1.54, 1.10 vs. 1.12 and 5 Gy vs. 14 Gy, respectively. Those of the spherical phantom were 1.04 vs. 1.83, 1.08 vs. 1.09 and 7 Gy vs. 26 Gy, respectively. The proposed SFF plans showed superior dose distributions compared to the VMAT plans.

  10. Collision cascades and sputtering induced by larger cluster ions

    International Nuclear Information System (INIS)

    Sigmund, P.

    1988-01-01

    Recent experimental work on larger cluster impact on solid surfaces suggests large deviations from the standard case of additive sputter yields both in the nuclear and electronic stopping regime. The paper concentrates on elastic collision cascades. In addition to very pronounced spike effects, two phenomena are pointed out that are specific to cluster bombardment. Multiple hits of cluster atoms on one and the same target atom may result in recoil atoms that move faster than the maximum recoil speed for monomer bombardment at the same projectile speed. This effect is important when the atomic mass of a beam atom is less than that of a target atom, M 1 2 . In the opposite case, M 1 >> M 2 , collisions between beam particles may accelerate some beam particles and slow down others. Some consequences are mentioned. Remarks on the nuclear stopping power of larger clusters and on electronic sputtering by cluster bombardment conclude the paper. 38 refs., 2 figs

  11. Technique using axicons for generating flat-top laser-beam profiles

    International Nuclear Information System (INIS)

    Viswanathan, V.K.; Woodfin, G.L.; Stahl, D.; Carpenter, J.P.; Kyrala, G.

    1983-01-01

    In certain fusion experiments using CO 2 lasers, like Helios, it is desired to produce a focal spot several times larger than the nominal focal spot, with a flat beam profile. The typical focal spot in Helios is roughly 70 μm and just defocussing the beam produces beam breakup, with several hot spots with roughly the original diameter, and a gaussian distribution. A number of schemes were tried to achieve a large spot with desired characteristics. These are described in the article. Axicons were found to produce spots with desired characteristics. Axicons are lenses or mirrors having a cone-shaped surface. The various schemes are described, as well as an experiment in Helios which confirmed that axicons produced the spots with desirable characteristics. Helios is an 8-beam CO 2 laser which produces 10 kJ at power in excess of 20 TW. It is currently being used for Laser Fusion studies at the Los Alamos National Laboratory

  12. Novel imaging and quality assurance techniques for ion beam therapy a Monte Carlo study

    CERN Document Server

    Rinaldi, I; Jäkel, O; Mairani, A; Parodi, K

    2010-01-01

    Ion beams exhibit a finite and well defined range in matter together with an “inverted” depth-dose profile, the so-called Bragg peak. These favourable physical properties may enable superior tumour-dose conformality for high precision radiation therapy. On the other hand, they introduce the issue of sensitivity to range uncertainties in ion beam therapy. Although these uncertainties are typically taken into account when planning the treatment, correct delivery of the intended ion beam range has to be assured to prevent undesired underdosage of the tumour or overdosage of critical structures outside the target volume. Therefore, it is necessary to define dedicated Quality Assurance procedures to enable in-vivo range verification before or during therapeutic irradiation. For these purposes, Monte Carlo transport codes are very useful tools to support the development of novel imaging modalities for ion beam therapy. In the present work, we present calculations performed with the FLUKA Monte Carlo code and pr...

  13. Design technique for all-dielectric non-polarizing beam splitter plate

    Science.gov (United States)

    Rizea, A.

    2012-03-01

    There are many situations when, for the proper working, an opto-electronic device requiring optical components does not change the polarization state of light after a reflection, splitting or filtering. In this paper, a design for a non-polarizing beam splitter plate is proposed. Based on certain optical properties of homogeneous dielectric materials we will establish a reliable thin film package formula, excellent for the start of optimization to obtain a 20-nm bandwidth non-polarizing beam splitter.

  14. Pumping behavior of sputter ion pumps

    International Nuclear Information System (INIS)

    Chou, T.S.; McCafferty, D.

    The ultrahigh vacuum requirements of ISABELLE is obtained by distributed pumping stations. Each pumping station consists of 1000 l/s titanium sublimation pump for active gases (N 2 , H 2 , O 2 , CO, etc.), and a 20 l/s sputter ion pump for inert gases (methane, noble gases like He, etc.). The combination of the alarming production rate of methane from titanium sublimation pumps (TSP) and the decreasing pumping speed of sputter ion pumps (SIP) in the ultrahigh vacuum region (UHV) leads us to investigate this problem. In this paper, we first describe the essential physics and chemistry of the SIP in a very clean condition, followed by a discussion of our measuring techniques. Finally measured methane, argon and helium pumping speeds are presented for three different ion pumps in the range of 10 -6 to 10 -11 Torr. The virtues of the best pump are also discussed

  15. Combined sputtering yield and surface topography development studies on Si

    International Nuclear Information System (INIS)

    Carter, G.; Nobes, M.J.; Lewis, G.W.; Whitton, J.L.

    1981-01-01

    The sputtering yield-incidence angle function has been measured for 8 keV Ar + ions incident on Si by direct scanning electron microscope observation of the depths of sputtered craters on substrate boundaries. This function displays a maximum sputtering yield at an angle thetasub(p) approximately equal to 40 0 to the surface normal. The sequential ion fluence dependence of features developed beneath local surface contaminant was then studied, quasi dynamically, in the same on-line ion source-S.E.M. system. During erosion of the contaminant a steeply elevated pillar of Si forms, which then transforms to a cone, again of high elevation angle >>thetasub(p). This cone is gradually eroded into the surrounding surface with no special significance associated with orientations of angle thetasub(p). Pedal depressions surrounding the pillar-cone system are also noted. The reasons for these observations and their relevance to ion beam surface channel etching are discussed. (Auth.)

  16. Examination of the metastable and stable pitting corrosion of aluminum modified with carbon by ion beam techniques

    International Nuclear Information System (INIS)

    Lensch, O.; Enders, B.; Knecht, J.; Ensinger, W.

    2001-01-01

    It is well known that aluminum and aluminum alloys are sensitive to pitting corrosion when exposed to aqueous solutions containing aggressive anions like halides. The destructive nature of pitting is due to its high local dissolution rates at electrode potentials above the so-called pitting potential U p . Recently, it has been realized that also at potentials below U p , in the passive and cathodic regions and around the free corrosion potential, anodic current transients appear which have been attributed to metastable pitting events. For the purpose of full characterization of the pitting behavior, a program routine has been developed where the occurrence frequency, lifetime and rate of metastable pitting events are extracted from potentiostatic current/time-measurements depending on the electrode potential. The routine has been applied to measurements of carbon modified pure aluminum. Carbon modifications were done with carbon evaporation and carbon sputtering under concurrent argon ion bombardment. The results are discussed in terms of the applied modification technique, their parameters and their effects on the corrosion protection ability of aluminum modified by carbon

  17. Composition and stratigraphy of the paint layers: investigation on the Madonna dei Fusi by ion beam analysis techniques

    Science.gov (United States)

    Grassi, N.

    2005-06-01

    In the framework of the extensive study on the wood painting "Madonna dei fusi" attributed to Leonardo da Vinci, Ion Beam Analysis (IBA) techniques were used at the Florence accelerator laboratory to get information about the elemental composition of the paint layers. After a brief description of the basic principle and the general features of IBA techniques, we will illustrate in detail how the analysis allowed us to characterise the pigments of original and restored areas and the substrate composition, and to obtain information about the stratigraphy of the painting, also providing an estimate of the paint layer thickness.

  18. Determination of boron in aqueous solutions by solid state nuclear track detectors technique, using a filtered neutron beam

    International Nuclear Information System (INIS)

    Moraes, M.A.P.V. de; Pugliesi, R.; Khouri, M.T.F.C.

    1985-11-01

    The solid state nuclear track detectors technique has been used for determination of boron in aqueous solutions, using a filtered neutron beam. The particles tracks from the 10 B(n,α)Li 7 reaction were registered in the CR-39 film, chemically etched in a (30%) KOH solution 70 0 C during 90 minutes. The obtained results showed the usefulness of this technique for boron determination in the ppm range. The inferior detectable limit was 9 ppm. The combined track registration efficiency factor K has been evaluated in the solutions, for the CR-39 detector and its values is K= (4,60 - + 0,06). 10 -4 cm. (Author) [pt

  19. An improved optical flow tracking technique for real-time MR-guided beam therapies in moving organs

    Science.gov (United States)

    Zachiu, C.; Papadakis, N.; Ries, M.; Moonen, C.; de Senneville, B. Denis

    2015-12-01

    Magnetic resonance (MR) guided high intensity focused ultrasound and external beam radiotherapy interventions, which we shall refer to as beam therapies/interventions, are promising techniques for the non-invasive ablation of tumours in abdominal organs. However, therapeutic energy delivery in these areas becomes challenging due to the continuous displacement of the organs with respiration. Previous studies have addressed this problem by coupling high-framerate MR-imaging with a tracking technique based on the algorithm proposed by Horn and Schunck (H and S), which was chosen due to its fast convergence rate and highly parallelisable numerical scheme. Such characteristics were shown to be indispensable for the real-time guidance of beam therapies. In its original form, however, the algorithm is sensitive to local grey-level intensity variations not attributed to motion such as those that occur, for example, in the proximity of pulsating arteries. In this study, an improved motion estimation strategy which reduces the impact of such effects is proposed. Displacements are estimated through the minimisation of a variation of the H and S functional for which the quadratic data fidelity term was replaced with a term based on the linear L1norm, resulting in what we have called an L2-L1 functional. The proposed method was tested in the livers and kidneys of two healthy volunteers under free-breathing conditions, on a data set comprising 3000 images equally divided between the volunteers. The results show that, compared to the existing approaches, our method demonstrates a greater robustness to local grey-level intensity variations introduced by arterial pulsations. Additionally, the computational time required by our implementation make it compatible with the work-flow of real-time MR-guided beam interventions. To the best of our knowledge this study was the first to analyse the behaviour of an L1-based optical flow functional in an applicative context: real-time MR

  20. Accurate technique for complete geometric calibration of cone-beam computed tomography systems

    International Nuclear Information System (INIS)

    Cho Youngbin; Moseley, Douglas J.; Siewerdsen, Jeffrey H.; Jaffray, David A.

    2005-01-01

    Cone-beam computed tomography systems have been developed to provide in situ imaging for the purpose of guiding radiation therapy. Clinical systems have been constructed using this approach, a clinical linear accelerator (Elekta Synergy RP) and an iso-centric C-arm. Geometric calibration involves the estimation of a set of parameters that describes the geometry of such systems, and is essential for accurate image reconstruction. We have developed a general analytic algorithm and corresponding calibration phantom for estimating these geometric parameters in cone-beam computed tomography (CT) systems. The performance of the calibration algorithm is evaluated and its application is discussed. The algorithm makes use of a calibration phantom to estimate the geometric parameters of the system. The phantom consists of 24 steel ball bearings (BBs) in a known geometry. Twelve BBs are spaced evenly at 30 deg in two plane-parallel circles separated by a given distance along the tube axis. The detector (e.g., a flat panel detector) is assumed to have no spatial distortion. The method estimates geometric parameters including the position of the x-ray source, position, and rotation of the detector, and gantry angle, and can describe complex source-detector trajectories. The accuracy and sensitivity of the calibration algorithm was analyzed. The calibration algorithm estimates geometric parameters in a high level of accuracy such that the quality of CT reconstruction is not degraded by the error of estimation. Sensitivity analysis shows uncertainty of 0.01 deg. (around beam direction) to 0.3 deg. (normal to the beam direction) in rotation, and 0.2 mm (orthogonal to the beam direction) to 4.9 mm (beam direction) in position for the medical linear accelerator geometry. Experimental measurements using a laboratory bench Cone-beam CT system of known geometry demonstrate the sensitivity of the method in detecting small changes in the imaging geometry with an uncertainty of 0.1 mm in

  1. Influence of external beam technique and brachytherapy quality assurance on the side effects in the combined external beam- and brachytherapy treatment of local advanced prostate cancer

    International Nuclear Information System (INIS)

    Kovacs, G.; Galalae, R.; Wirth, B.; Bertermann, H.; Wilhelm, R.; Kohr, P.; Kimmig, B.

    1996-01-01

    Transrectal ultrasound(TRUS) guided HDR implantation of the prostate has been established at the Kiel University by Bertermann and Brix in 1986 and there are to date 179 (T1b-T3 No Mo) patients treated in a combined modality. The dose for the implant was 2x 15 Gy on the capsule of the prostate in 14-20 days. For local and regional lymph nodes 20 Gy external beam therapy (AP-PA pelvic portals), 20 Gy with an individual transmission block (100% for subclinical disease, 70% and 50% according to the implant dosimetry for the prostate) and 10 Gy small volume irradiation for the prostate was applied, conventional fractioned. Total dose after the therapy 70 Gy for the prostate and 50 Gy for the subclinical disease in 6-7 weeks. As a quality control method we use since 1991 in vivo dosimetry on the medial rectum wall as well as in the prostatic part of the urethra. Regular follow-up 3-118 months after therapy (median 55) with PSA, digital rectal examination, control TRUS with volumetry (after one year with biopsy) and bone scan. There were no major early side effects within the first three months. Proctitis till 1991 with a duration up to 12 months 49%, prolonging more than one year in 23 %, (total proctitis 72.6%). Dysuria in up to 12 months 30 %, long lasting 30% (total number of dysuria 60 %). Erectile dysfunction in 56 %. Because of the number of the side effects 1991 we changed the external beam technique: instead of the biaxial arch therapy the AP-PA portals, and reduced irradiated volume (from 6480 cm 3 to 5040 cm 3 ). We introduced instead of the small volume arch therapy for 10 Gy external boost the box-technique with shielding the back part of the rectum and the upper part of the bladder resulting additional volume reduction. Through the 15 Gy HDR brachytherapy dose on the prostate capsule there are up to 8 Gy on the medial rectal wall, measured by in vivo dosimetry. This dose could not be responsible for the high number of side effects (see gynecological

  2. Exploring the Spatial Resolution of the Photothermal Beam Deflection Technique in the Infrared Region

    CERN Document Server

    Seidel, Wolfgang

    2004-01-01

    In photothermal beam deflection spectroscopy (PTBD) generating and detection of thermal waves occur generally in the sub-millimeter length scale. Therefore, PTBD provides spatial information about the surface of the sample and permits imaging and/or microspectrometry. Recent results of PTBD experiments are presented with a high spatial resolution which is near the diffraction limit of the infrared pump beam (CLIO-FEL). We investigated germanium substrates showing restricted O+-doped regions with an infrared absorption line at a wavelength around 11.6 microns. The spatial resolution was obtained by strongly focusing the probe beam (i.e. a HeNe laser) on a sufficiently small spot. The strong divergence makes it necessary to refocus the probe beam in front of the position detector. The influence of the focusing elements on spatial resolution and signal-to-noise ratio is discussed. In future studies we expect an enhanced spatial resolution due to an extreme focusing of the probe beam leading to a highly sensitive...

  3. Initial Imaging of 7-GeV Electron Beams with OTR/ODR Techniques at APS

    CERN Document Server

    Lumpkin, Alex H; Sereno, Nicholas S; Yao, Chihyuan

    2005-01-01

    The development of nonintercepting (NI) diagnostics continues to be of interest at the Advanced Photon Source (APS) as well as elsewhere. In the three rings of the APS facility we use optical synchrotron radiation generated as the electron beam transits the dipole magnetic fields as an NI mechanism to image the beam during top-up operations. However, in the straight transport lines an alternative method is needed. Optical diffraction radiation (ODR) is under investigation to monitor 7-GeV beam trajectory and potentially transverse shape in the booster-to-storage ring (BTS) beamline during top-up operations. We have performed our initial measurements with an Al blade/mirror that served as an optical transition radiation (OTR) monitor when fully inserted into the beam and as an ODR monitor when the beam passed near the edge. In the case of ODR, appreciable signal is emitted by the metal when gamma times the reduced ODR wavelength is comparable to the impact parameter, where gamma is the Lorentz factor. Visible ...

  4. Energy sharing and sputtering in low-energy collision cascades

    International Nuclear Information System (INIS)

    Weller, R.A.; Weller, M.R.

    1982-01-01

    Using a non-linear transport equation to describe the energy-sharing process in an isotropic collision cascade, we have numerically calculated sputtered particle velocity spectra for several very low energy (=< 10 eV) primary recoil distributions. Our formulation of the sputtering process is essentially that used in the linear model and our equations yield the familiar linear model results in the appropriate limit. Discrepancies between our calculations and the linear model results in other cases may be understood by considering the effects of the linear model assumptions on the sputtering yield at very low energies. Our calculations are also compared with recent experimental results investigating ion-explosion sputtering. The results of this comparison support the conclusion that in insulators sputtering is initiated by very low energy recoil atoms when the energy of the incident beam is high enough that the stopping power is dominated by the electronic contribution. The calculations also suggest that energy spectra similar to those for evaporation may result from non-equilibrium processes but that the apparent temperatures of evaporation are not related in a simple way to any real temperature within the target. (author)

  5. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    International Nuclear Information System (INIS)

    Abat, E; Arik, E; Abdallah, J M; Addy, T N; Adragna, P; Aharrouche, M; Ahmad, A; Akesson, T P A; Aleksa, M; Anghinolfi, F; Baron, S; Alexa, C; Anderson, K; Andreazza, A; Banfi, D; Antonaki, A; Arabidze, G; Atkinson, T; Baines, J; Baker, O K

    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 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.

  6. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    Energy Technology Data Exchange (ETDEWEB)

    Abat, E; Arik, E [Bogazici University, Faculty of Sciences, Department of Physics, TR - 80815 Bebek-Istanbul (Turkey); Abdallah, J M [Institut de Fisica d' Altes Energies, IFAE, Universitat Autonoma de Barcelona, Edifici Cn, ES - 08193 Bellaterra (Barcelona) Spain (Spain); Addy, T N [Hampton University, Department of Physics, Hampton, VA 23668 (United States); Adragna, P [Queen Mary, University of London, Mile End Road, E1 4NS, London (United Kingdom); Aharrouche, M [Universitaet Mainz, Institut fuer Physik, Staudinger Weg 7, DE 55099 (Germany); Ahmad, A [Insitute of Physics, Academia Sinica, TW - Taipei 11529, Taiwan (China); Akesson, T P A [Lunds universitet, Naturvetenskapliga fakulteten, Fysiska institutionen, Box 118, SE - 221 00, Lund (Sweden); Aleksa, M; Anghinolfi, F; Baron, S [European Laboratory for Particle Physics CERN, CH-1211 Geneva 23 (Switzerland); Alexa, C [National Institute of Physics and Nuclear Engineering (Bucharest -IFIN-HH), P.O. Box MG-6, R-077125 Bucharest (Romania); Anderson, K [University of Chicago, Enrico Fermi Institute, 5640 S. Ellis Avenue, Chicago, IL 60637 (United States); Andreazza, A; Banfi, D [INFN Sezione di Milano, via Celoria 16, IT - 20133 Milano (Italy); Antonaki, A; Arabidze, G [University of Athens, Nuclear and Particle Physics Department of Physics, Panepistimiopouli Zografou, GR 15771 Athens (Greece); Atkinson, T [School of Physics, University of Melbourne, AU - Parkvill, Victoria 3010 (Australia); Baines, J [Rutherford Appleton Laboratory, Science and Technology Facilities Council, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom); Baker, O K, E-mail: kjg@particle.kth.se [Yale University, Department of Physics , PO Box 208121, New Haven, CT06520-8121 (United States)

    2011-06-15

    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. Comparison of Techniques to Reduce Bremsstrahlung Background Radiation from Monoenergetic Photon Beams

    International Nuclear Information System (INIS)

    Johnson, M; McNabb, D

    2006-01-01

    An important applied technology is a tunable mono-energetic photon source [1]. These sources are made of relativistic electron accelerators coupled to low-energy lasers, which produce high-energy, mono-energetic-rays. One challenge associated with systems such as this is a continuum of bremsstrahlung background created when an electron beam passes through an aperture of some sort and the electron bunch or its halo impinges on the aperture pictured in figure 1. For instance, in the current T-REX [1] design for the interaction point between the laser- and electron-beam, the electron-beam passes through the center of a mirror used to reflect the laser. There is a potential with this design that bremsstrahlung radiation may be produced at the edges of the mirror openings and contaminate the mono-energetic photon beam. Certain applications [2] may be sensitive to this contamination. To reduce the bremsstrahlung contaminate a collimator (thickness ∼24in. (calculated from XCOM database [3]) to attenuate by a factor of 10 -3 the 112MeV photons expected in the T-REX demonstration [1]) is situated between the aperture and target. To maximize the brightness of the photon-beam, the collimator opening must be no less than the size of the photon-beam spot size expected to be about 1mm. This fixes the collimator opening. a priori the aperture size must be greater than the collimator opening and is a function distance between the aperture and collimator. In this paper we focus on two approaches to estimate the aperture size, given a collimator and a target whose sizes and distances from the aperture are given. In the next section we will discuss these approaches

  8. Prototype inverted sputter source for negative heavy ions

    International Nuclear Information System (INIS)

    Minehara, Eisuke; Kobayashi, Chiaki; Kikuchi, Shiroh

    1977-10-01

    A sputter source from which negative heavy ion beam is extracted through a tungsten wire and disc ionizer was built and tested. An alkali metal surface ionization gun with the ionizer is described, and also performance of the surface ionization gun and of the sputter source for negative heavy ions using the gun is reported. The gun was tested for three alkali metals, i.e. sodium, potassium and cesium. Total potassium beam current of 1-2mA was obtained at entrance aperture of the magnet. Sputtering materials and gases for producing negative heavy ions are carbon, copper, aluminium, molybdenum, oxygen and air. With carbon and leakage air, the beam intensities analyzed are: 2-5μA (at Faraday cup) and 4.6-11μA (at exit slit) for C - , 3-5μA (at Faraday cup) and 6.8-11μA (at exit slit) for 2C - , and 11-15μA (at Faraday cup) and 25-34μA (at exit slit) for O - . Total beam current at the entrance aperture was 200-400μA. (auth.)

  9. Sputtering of a silicon surface: Preferential sputtering of surface impurities

    Czech Academy of Sciences Publication Activity Database

    Nietiadi, M.L.; Rosandi, Y.; Lorinčík, Jan; Urbassek, H.M.

    -, č. 303 (2013), s. 205-208 ISSN 0168-583X Institutional support: RVO:67985882 Keywords : Sputtering * Molecular dynamics * SIMS Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.186, year: 2013

  10. Studies on the dose distribution and treatment technique of high energy electron beams

    International Nuclear Information System (INIS)

    Lee, D.H.; Chu, S.S.

    1978-01-01

    Some important properties of high energy electron beams from the linear accelerator, LMR-13, installed in the Yonsei Cancer Center were studied. The results of experimental studies on the problems associated with the 8, 10, and 12 MeV electron beam therapy were as followings; The ionization type dosemeters calibrated by 90 Sr standard source were suitable to the measurements of the outputs and the obsorbed doses in accuracy point of view, and dose measurements using ionization chambers were difficult when measuring doses in small field size and the regions of rapid fall off. The electron energies were measured precisely with an energy spectrometer, and the practical electron energy was calculated within 5% error in the maximum range of the high energy electron beam in water. The correcting factors of perturbated dose distributions owing to radiation field, energy, and materials of the treatment cone were checked and described systematically and thus the variation of dose distributions due to the non-homogeneities of tissues and slopping skin surfaces were completely compensated. The electron beams were adequately diffused using the scatterers, and minimized the bremsstrahlung, irradiation field size, and materials of scatterers. Thus, the therapeutic capacity with the limited electron energy could be extended by improving the dose distributions. (author)

  11. Heterogeneous chemical kinetics by modulated molecular beam mass spectrometry: limitations of technique

    International Nuclear Information System (INIS)

    Olander, D.R.

    1977-01-01

    The advantages and limitations of modulated molecular beam, mass spectrometry as applied to the study of heterogeneous chemical kinetics are reviewed. The process of deducing a model of the surface reaction from experimental data is illustrated by analysis of the hydrogen reduction of uranium dioxide

  12. Stacking fault energy measurements in WSe2 single crystals using weak-beam techniques

    International Nuclear Information System (INIS)

    Agarwal, M.K.; Patel, J.V.; Patel, N.G.

    1981-01-01

    The weak-beam method of electron microscopy is used to observe threefold dislocations in WSe 2 single crystals grown by direct vapour transport method. The widths of the three fold ribbons are used to determine the stacking fault energy in these crystals. Variation of the width of the ribbons with temperature are also studied and discussed. (author)

  13. Glass Fiber Reinforced Polymer (GFRP Bars for Enhancing the Flexural Performance of RC Beams Using Side-NSM Technique

    Directory of Open Access Journals (Sweden)

    Md. Akter Hosen

    2017-05-01

    Full Text Available Reinforced concrete (RC structures require strengthening for numerous factors, such as increased load, modification of the structural systems, structural upgrade or errors in the design and construction stages. The side near-surface mounted (SNSM strengthening technique with glass fiber-reinforced polymer (GFRP bars is a relatively new emerging technique for enhancing the flexural capacities of existing RC elements. Nine RC rectangular beams were flexurally strengthened with this technique and tested under four-point bending loads until failure. The main goal of this study is to optimize the structural capacity of the RC beams by varying the amount of strengthening reinforcement and bond length. The experimental test results showed that strengthening with SNSM GFRP bars significantly enhanced the flexural responses of the specimens compared with the control specimen. The first cracking and ultimate loads, energy absorption capacities, ductility and stiffness were remarkably enhanced by the SNSM technique. It was also confirmed that the bond length of the strengthened reinforcement greatly influences the energy absorption capacities, ductility and stiffness. The effect of the bond length on these properties is more significant compared to the amount of strengthening reinforcement.

  14. Setup for in situ X-ray diffraction studies of thin film growth by magnetron sputtering

    CERN Document Server

    Ellmer, K; Weiss, V; Rossner, H

    2001-01-01

    A novel method is described for the in situ-investigation of nucleation and growth of thin films during magnetron sputtering. Energy dispersive X-ray diffraction with synchrotron light is used for the structural analysis during film growth. An in situ-magnetron sputtering chamber was constructed and installed at a synchrotron radiation beam line with a bending magnet. The white synchrotron light (1-70 keV) passes the sputtering chamber through Kapton windows and hits one of the substrates on a four-fold sample holder. The diffracted beam, observed under a fixed diffraction angle between 3 deg. and 10 deg., is energy analyzed by a high purity Ge-detector. The in situ-EDXRD setup is demonstrated for the growth of tin-doped indium oxide (ITO) films prepared by reactive magnetron sputtering from a metallic target.

  15. Quartz crystal microbalance-based system for high-sensitivity differential sputter yield measurements

    International Nuclear Information System (INIS)

    Rubin, B.; Topper, J. L.; Farnell, C. C.; Yalin, A. P.

    2009-01-01

    We present a quartz crystal microbalance-based system for high sensitivity differential sputter yield measurements of different target materials due to ion bombardment. The differential sputter yields can be integrated to find total yields. Possible ion beam conditions include ion energies in the range of 30-350 eV and incidence angles of 0 deg. - 70 deg. from normal. A four-grid ion optics system is used to achieve a collimated ion beam at low energy (<100 eV) and a two-grid ion optics is used for higher energies (up to 750 eV). A complementary weight loss approach is also used to measure total sputter yields. Validation experiments are presented that confirm high sensitivity and accuracy of sputter yield measurements.

  16. Study of SiO{sub 2} surface sputtering by a 250-550 keV He{sup +} ion beam during high-resolution Rutherford backscattering measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kusanagi, Susumu [Materials Analysis Laboratory, Advanced Design Technology Center, Sony Corporation, 4-16-1 Okata Atsugi-shi, Kanagawa 243-0021 (Japan)]. E-mail: susumu.kusanagi@jp.sony.com; Kobayashi, Hajime [Materials Analysis Laboratory, Advanced Design Technology Center, Sony Corporation, 4-16-1 Okata Atsugi-shi, Kanagawa 243-0021 (Japan)

    2006-08-15

    Decreases in oxygen signal intensities in spectra of high-resolution Rutherford backscattering spectrometry (HRBS) were observed during measurements on a 5-nm thick SiO{sub 2} layer on a Si substrate when irradiated by 250-550 keV He{sup +} ions. Shifts in an implanted arsenic profile in a 5-nm thick SiO{sub 2}/Si substrate were also observed as a result of He{sup +} ion irradiation. These results lead to the conclusion that the SiO{sub 2} surface was sputtered by He{sup +} ions in this energy range.

  17. Conventional and conformal technique of external beam radiotherapy in locally advanced cervical cancer: Dose distribution, tumor response, and side effects

    Science.gov (United States)

    Mutrikah, N.; Winarno, H.; Amalia, T.; Djakaria, M.

    2017-08-01

    The objective of this study was to compare conventional and conformal techniques of external beam radiotherapy (EBRT) in terms of the dose distribution, tumor response, and side effects in the treatment of locally advanced cervical cancer patients. A retrospective cohort study was conducted on cervical cancer patients who underwent EBRT before brachytherapy in the Radiotherapy Department of Cipto Mangunkusumo Hospital. The prescribed dose distribution, tumor response, and acute side effects of EBRT using conventional and conformal techniques were investigated. In total, 51 patients who underwent EBRT using conventional techniques (25 cases using Cobalt-60 and 26 cases using a linear accelerator (LINAC)) and 29 patients who underwent EBRT using conformal techniques were included in the study. The distribution of the prescribed dose in the target had an impact on the patient’s final response to EBRT. The complete response rate of patients to conformal techniques was significantly greater (58%) than that of patients to conventional techniques (42%). No severe acute local side effects were seen in any of the patients (Radiation Therapy Oncology Group (RTOG) grades 3-4). The distribution of the dose and volume to the gastrointestinal tract affected the proportion of mild acute side effects (RTOG grades 1-2). The urinary bladder was significantly greater using conventional techniques (Cobalt-60/LINAC) than using conformal techniques at 72% and 78% compared to 28% and 22%, respectively. The use of conformal techniques in pelvic radiation therapy is suggested in radiotherapy centers with CT simulators and 3D Radiotherapy Treatment Planning Systems (RTPSs) to decrease some uncertainties in radiotherapy planning. The use of AP/PA pelvic radiation techniques with Cobalt-60 should be limited in body thicknesses equal to or less than 18 cm. When using conformal techniques, delineation should be applied in the small bowel, as it is considered a critical organ according to RTOG

  18. Post-excitation of sputtered neutral atoms and application to the surface microanalysis by ionoluminescence

    International Nuclear Information System (INIS)

    Bourdilot, M.; Paletto, S.; Goutte, R.; Guillaud, C.

    1975-01-01

    During the bombardment of a solid target by a positive ion beam, an emission of light proceeding of the deexcitation of the neutral atoms which are sputtered in an excited state, is observed. This phenomenon is used in ionoluminescence analysis. By exciting the neutral atoms sputtered with an auxiliary discharge it is seen that: it is possible to increase, under certain experimental conditions, the sensibility of the ionoluminescence method. This post-excitation is particularly efficient with targets having an high sputtering coefficient [fr

  19. SU-F-T-188: A Robust Treatment Planning Technique for Proton Pencil Beam Scanning Cranial Spinal Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, M; Mehta, M; Badiyan, S; Young, K; Malyapa, R; Regine, W; Langen, K [University of Maryland School of Medicine, Baltimore, MD (United States); Yam, M [University of Florida Proton Therapy Institute, Jacksonville, FL (United States)

    2016-06-15

    Purpose: To propose a proton pencil beam scanning (PBS) cranial spinal irradiation (CSI) treatment planning technique robust against patient roll, isocenter offset and proton range uncertainty. Method: Proton PBS plans were created (Eclipse V11) for three previously treated CSI patients to 36 Gy (1.8 Gy/fractions). The target volume was separated into three regions: brain, upper spine and lower spine. One posterior-anterior (PA) beam was used for each spine region, and two posterior-oblique beams (15° apart from PA direction, denoted as 2PO-15) for the brain region. For comparison, another plan using one PA beam for the brain target (denoted as 1PA) was created. Using the same optimization objectives, 98% CTV was optimized to receive the prescription dose. To evaluate plan robustness against patient roll, the gantry angle was increased by 3° and dose was recalculated without changing the proton spot weights. On the re-calculated plan, doses were then calculated using 12 scenarios that are combinations of isocenter shift (±3mm in X, Y, and Z directions) and proton range variation (±3.5%). The worst-case-scenario (WCS) brain CTV dosimetric metrics were compared to the nominal plan. Results: For both beam arrangements, the brain field(s) and upper-spine field overlap in the T2–T5 region depending on patient anatomy. The maximum monitor unit per spot were 48.7%, 47.2%, and 40.0% higher for 1PA plans than 2PO-15 plans for the three patients. The 2PO-15 plans have better dose conformity. At the same level of CTV coverage, the 2PO-15 plans have lower maximum dose and higher minimum dose to the CTV. The 2PO-15 plans also showed lower WCS maximum dose to CTV, while the WCS minimum dose to CTV were comparable between the two techniques. Conclusion: Our method of using two posterior-oblique beams for brain target provides improved dose conformity and homogeneity, and plan robustness including patient roll.

  20. A cone beam CT-guided online plan modification technique to correct interfractional anatomic changes for prostate cancer IMRT treatment

    International Nuclear Information System (INIS)

    Fu Weihua; Yang Yong; Yue, Ning J; Heron, Dwight E; Huq, M Saiful

    2009-01-01

    The purpose of this work is to develop an online plan modification technique to compensate for the interfractional anatomic changes for prostate cancer intensity-modulated radiation therapy (IMRT) treatment based on daily cone beam CT (CBCT) images. In this proposed technique, pre-treatment CBCT images are acquired after the patient is set up on the treatment couch using an in-room laser with the guidance of the setup skin marks. Instead of moving the couch to rigidly align the target or re-planning using the CBCT images, we modify the original IMRT plan to account for the interfractional target motion and deformation based on the daily CBCT image feedback. The multileaf collimator (MLC) leaf positions for each subfield are automatically adjusted in the proposed algorithm based on the position and shape changes of target projection in the beam's eye view (BEV). Three typical prostate cases were adopted to evaluate the proposed technique, and the results were compared with those obtained with bony-structure-based rigid translation correction, prostate-based correction and CBCT-based re-planning strategies. The study revealed that the proposed modification technique is superior to the bony-structure-based and prostate-based correction techniques, especially when interfractional target deformation exists. Its dosimetric performance is closer to that of the re-planned strategy, but with much higher efficiency, indicating that the introduced online CBCT-guided plan modification technique may be an efficient and practical method to compensate for the interfractional target position and shape changes for prostate IMRT.

  1. Cone beam computed tomography in veterinary dentistry: description and standardization of the technique

    International Nuclear Information System (INIS)

    Roza, Marcello R.; Silva, Luiz A.F.; Fioravanti, Maria C. S.; Barriviera, Mauricio

    2009-01-01

    Eleven dogs and four cats with buccodental alterations, treated in the Centro Veterinario do Gama, in Brasilia, DF, Brazil, were submitted to cone beam computed tomography. The exams were carried out in a i-CAT tomograph, using for image acquisition six centimeters height, 40 seconds time, 0.2 voxel, 120 kilovolts and 46.72 milli amperes per second. The ideal positioning of the animal for the exam was also determined in this study and it proved to be fundamental for successful examination, which required a simple and safe anesthetic protocol due to the relatively short period of time necessary to obtain the images. Several alterations and diseases were identified with accurate imaging, demonstrating that cone beam computed tomography is a safe, accessible and feasible imaging method which could be included in the small animal dentistry routine diagnosis. (author)

  2. Development of the techniques for food processing with low-energy electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Todoroki, Setsuko; Hayashi, Toru [National Food Research Inst., Tsukuba, Ibaraki (Japan)

    1999-02-01

    This study aimed to construct a new electron beam irradiation apparatus which allows to perform homogeneous irradiation up to a certain depth of a spherical or granular material through rotating it. And the sterilizing effects of this apparatus on various kinds of spices such as black and white peppers (grains), turmeric (root), coriander (seed), basil (leaves) were investigated to compare with the effects of {gamma}-ray irradiation. Electron beam irradiation was made changing the energy form 200 keV for 15 min to 500 keV for 5 min and a dose-depth curve was drawn for each electron energy. Indicator balls were used to examine the radiation effects. It became possible to make homogeneous irradiation onto a spherical surface of food by using the rotary system of the apparatus. It was demonstrated that satisfactory sterilizing effects as much as those of {gamma}-ray were obtainable by superficial treatments with low-energy electron. (M.N.)

  3. Development of the techniques for food processing with low-energy electron beam

    International Nuclear Information System (INIS)

    Todoroki, Setsuko; Hayashi, Toru

    1999-01-01

    This study aimed to construct a new electron beam irradiation apparatus which allows to perform homogeneous irradiation up to a certain depth of a spherical or granular material through rotating it. And the sterilizing effects of this apparatus on various kinds of spices such as black and white peppers (grains), turmeric (root), coriander (seed), basil (leaves) were investigated to compare with the effects of γ-ray irradiation. Electron beam irradiation was made changing the energy form 200 keV for 15 min to 500 keV for 5 min and a dose-depth curve was drawn for each electron energy. Indicator balls were used to examine the radiation effects. It became possible to make homogeneous irradiation onto a spherical surface of food by using the rotary system of the apparatus. It was demonstrated that satisfactory sterilizing effects as much as those of γ-ray were obtainable by superficial treatments with low-energy electron. (M.N.)

  4. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    OpenAIRE

    Kovalenko, S.; Khoriauli, G.; C. Driouchi; J. D. Peso; L. Santi; Soloviev, I.; Arik, E.; Bernabeu, J; M. V. Castillo; Atkinson, T; Tegenfeldt, F.; Weidberg, A.R.; Røhne, O.; F. Anghinolfi; S. Chouridou

    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...

  5. In Situ TEM Multi-Beam Ion Irradiation as a Technique for Elucidating Synergistic Radiation Effects

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Caitlin; Bufford, Daniel; Muntifering, Brittany; Senor, David; Steckbeck, Mackenzie; Davis, Justin; Doyle, Barney; Buller, Daniel; Hattar, Khalid

    2017-09-29

    Materials designed for nuclear reactors undergo microstructural changes resulting from a combination of several environmental factors, including neutron irradiation damage, gas accumulation and elevated temperatures. Typical ion beam irradiation experiments designed for simulating a neutron irradiation environment involve irradiating the sample with a single ion beam and subsequent characterization of the resulting microstructure, often by transmission electron microscopy (TEM). This method does not allow for examination of microstructural effects due to simultaneous gas accumulation and displacement cascade damage, which occurs in a reactor. Sandia’s in situ ion irradiation TEM (I3TEM) offers the unique ability to observe microstructural changes due to irradiation damage caused by concurrent multi-beam ion irradiation in real time. This allows for time-dependent microstructure analysis. A plethora of additional in situ stages can be coupled with these experiments, e.g., for more accurately simulating defect kinetics at elevated reactor temperatures. This work outlines experiments showing synergistic effects in Au using in situ ion irradiation with various combinations of helium, deuterium and Au ions, as well as some initial work on materials utilized in tritium-producing burnable absorber rods (TPBARs): zirconium alloys and LiAlO2.

  6. In Situ TEM Multi-Beam Ion Irradiation as a Technique for Elucidating Synergistic Radiation Effects

    Directory of Open Access Journals (Sweden)

    Caitlin Anne Taylor

    2017-09-01

    Full Text Available Materials designed for nuclear reactors undergo microstructural changes resulting from a combination of several environmental factors, including neutron irradiation damage, gas accumulation and elevated temperatures. Typical ion beam irradiation experiments designed for simulating a neutron irradiation environment involve irradiating the sample with a single ion beam and subsequent characterization of the resulting microstructure, often by transmission electron microscopy (TEM. This method does not allow for examination of microstructural effects due to simultaneous gas accumulation and displacement cascade damage, which occurs in a reactor. Sandia’s in situ ion irradiation TEM (I3TEM offers the unique ability to observe microstructural changes due to irradiation damage caused by concurrent multi-beam ion irradiation in real time. This allows for time-dependent microstructure analysis. A plethora of additional in situ stages can be coupled with these experiments, e.g., for more accurately simulating defect kinetics at elevated reactor temperatures. This work outlines experiments showing synergistic effects in Au using in situ ion irradiation with various combinations of helium, deuterium and Au ions, as well as some initial work on materials utilized in tritium-producing burnable absorber rods (TPBARs: zirconium alloys and LiAlO2.

  7. Depth profile analysis of thin TiOxNy films using standard ion beam analysis techniques and HERDA

    International Nuclear Information System (INIS)

    Markwitz, A.; Dytlewski, N.; Cohen, D.

    1999-01-01

    Ion beam assisted deposition is used to fabricate thin titanium oxynitride films (TiO x N y ) at Industrial Research (typical film thickness 100nm). At the Institute of Geological and Nuclear Sciences, the thin films are analysed using non-destructive standard ion beam analysis (IBA) techniques. High-resolution titanium depth profiles are measured with RBS using 1.5MeV 4 He + ions. Non-resonant nuclear reaction analysis (NRA) is performed for investigating the amounts of O and N in the deposited films using the reactions 16 O(d,p) 17 O at 920 keV and 14 N(d,α) 12 C at 1.4 MeV. Using a combination of these nuclear techniques, the stoichiometry as well as the thickness of the layers is revealed. However, when oxygen and nitrogen depth profiles are required for investigating stoichiometric changes in the films, additional nuclear analysis techniques such as heavy ion elastic recoil detection (HERDA) have to be applied. With HERDA, depth profiles of N, O, and Ti are measured simultaneously. In this paper comparative IBA measurement s of TiO x N y films with different compositions are presented and discussed

  8. Modified electron beam induced current technique for in(Ga)As/InAsSb superlattice infrared detectors

    Science.gov (United States)

    Yoon, N.; Reyner, C. J.; Ariyawansa, G.; Duran, J. M.; Scheihing, J. E.; Mabon, J.; Wasserman, D.

    2017-08-01

    Electron beam induced current (EBIC) measurements provide a powerful tool for characterizing semiconductor based materials and devices. By measuring the current generated by the electron beam of a scanning electron microscope (SEM), EBIC allows us to extract the minority carrier diffusion length (L) and the surface recombination velocity to diffusivity ratio (S/D) of a material. When combined with information on minority carrier lifetime (τ), for instance from time-resolved photoluminescence measurements, the minority carrier mobility of the material can be extracted. However, the EBIC technique relies heavily on the accurate modeling of the carrier generation and collection process. Traditionally, this was achieved using a combination of empirical analytical expressions (and later Monte Carlo simulations) for carrier generation and analytical diffusion/recombination expressions for carrier collection. This approach introduces significant uncertainties into the extracted material parameters. Here, we present a numerical approach to EBIC modeling which improves the spatial resolution of our model, while also retaining information regarding the relative EBIC signal as a function of incident beam energies and currents. We apply this technique to investigate the temperature dependent minority carrier mobility of InAs/InAsSb and InGaAs/InAsSb strained layer superlattice infrared detectors and compare our results to the values obtained using external quantum efficiency measurements of the same samples. Our approach not only allows for an improvement in the uncertainty of the extracted material parameters, but also offers insight into the material and device behavior as a function of nonequilibrium carrier concentration. The technique presented here offers potentially improved characterization of not only infrared detectors, but a range of semiconductor-based devices.

  9. Synthesis of dynamic phase profile by the correlation technique for spatial control of optical beams in multiplexing and switching

    Science.gov (United States)

    Bugaychuk, Svitlana A.; Gnatovskyy, Vladimir O.; Sidorenko, Andrey V.; Pryadko, Igor I.; Negriyko, Anatoliy M.

    2015-11-01

    New approach for the correlation technique, which is based on multiple periodic structures to create a controllable angular spectrum, is proposed and investigated both theoretically and experimentally. The transformation of an initial laser beam occurs due to the actions of consecutive phase periodic structures, which may differ by their parameters. Then, after the Fourier transformation of a complex diffraction field, the output diffraction orders will be changed both by their intensities and by their spatial position. The controllable change of output angular spectrum is carried out by a simple control of the parameters of the periodic structures. We investigate several simple examples of such management.

  10. Pulse radiolysis based on a femtosecond electron beam and a femtosecond laser light with double-pulse injection technique

    International Nuclear Information System (INIS)

    Yang Jinfeng; Kondoh, Takafumi; Kozawa, Takahiro; Yoshida, Youichi; Tagawa, Seiichi

    2006-01-01

    A new pulse radiolysis system based on a femtosecond electron beam and a femtosecond laser light with oblique double-pulse injection was developed for studying ultrafast chemical kinetics and primary processes of radiation chemistry. The time resolution of 5.2 ps was obtained by measuring transient absorption kinetics of hydrated electrons in water. The optical density of hydrated electrons was measured as a function of the electron charge. The data indicate that the double-laser-pulse injection technique was a powerful tool for observing the transient absorptions with a good signal to noise ratio in pulse radiolysis

  11. Dynamic characterization, monitoring and control of rotating flexible beam-mass structures via piezo-embedded techniques

    Science.gov (United States)

    Lai, Steven H.-Y.

    1992-01-01

    A variational principle and a finite element discretization technique were used to derive the dynamic equations for a high speed rotating flexible beam-mass system embedded with piezo-electric materials. The dynamic equation thus obtained allows the development of finite element models which accommodate both the original structural element and the piezoelectric element. The solutions of finite element models provide system dynamics needed to design a sensing system. The characterization of gyroscopic effect and damping capacity of smart rotating devices are addressed. Several simulation examples are presented to validate the analytical solution.

  12. Assembling of a low energy ion beam analysis facility and use of Nuclear Microprobe techniques in geological studies

    Energy Technology Data Exchange (ETDEWEB)

    Utui, R

    1996-11-01

    In this work, both PIXE and ion beam induced luminescence, or just Ionoluminescence (IL) were used for geochemical studies. The possibility of rapid absolute quantification of elements in the ppm level by PIXE combined with the yet higher sensitivity of IL to transition metals and Rare Earth Elements (REE) activators, in the absence of quenching phenomena, allow for a synergic use of the two methods in geological applications with enhanced sensitivity. IL and PIXE were combined for studying REE distribution in apatite minerals and ion beam induced damage in inorganic material in general with emphasis to synthetically grown zircon crystals doped with REE. Due to the sensitivity of IL to changes in chemical bonding in the material, beam damage effects can be studied even at low integrated doses, through wavelength shift or fading of the induced light. Micro PIXE technique was used for studying profile concentrations of trace elements in pyrite grains and of elements used as geothermometers. Geothermometry allowed to assess the cooling rates in iron meteorites and the mineralization conditions in metamorphic rocks, attempting to describe the tectonic history of the terranes, with application in petrologic studies and geological prospecting. 148 refs.

  13. Assembling of a low energy ion beam analysis facility and use of Nuclear Microprobe techniques in geological studies

    International Nuclear Information System (INIS)

    Utui, R.

    1996-11-01

    In this work, both PIXE and ion beam induced luminescence, or just Ionoluminescence (IL) were used for geochemical studies. The possibility of rapid absolute quantification of elements in the ppm level by PIXE combined with the yet higher sensitivity of IL to transition metals and Rare Earth Elements (REE) activators, in the absence of quenching phenomena, allow for a synergic use of the two methods in geological applications with enhanced sensitivity. IL and PIXE were combined for studying REE distribution in apatite minerals and ion beam induced damage in inorganic material in general with emphasis to synthetically grown zircon crystals doped with REE. Due to the sensitivity of IL to changes in chemical bonding in the material, beam damage effects can be studied even at low integrated doses, through wavelength shift or fading of the induced light. Micro PIXE technique was used for studying profile concentrations of trace elements in pyrite grains and of elements used as geothermometers. Geothermometry allowed to assess the cooling rates in iron meteorites and the mineralization conditions in metamorphic rocks, attempting to describe the tectonic history of the terranes, with application in petrologic studies and geological prospecting. 148 refs

  14. Pulsed and monoenergetic beams for neutron cross-section measurements using activation and scattering techniques at Triangle Universities Nuclear Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Hutcheson, A. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States)]. E-mail: hutch@tunl.duke.edu; Angell, C.T. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Becker, J.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Boswell, M. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Crowell, A.S. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Dashdorj, D. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Fallin, B. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Fotiades, N. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Howell, C.R.; Karwowski, H.J.; Kelley, J.H.; Kiser, M. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Macri, R.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Nelson, R.O. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Pedroni, R.S. [NC A and T State University, 1601 East Market Street, Greensboro, NC 27411 (United States); Tonchev, A.P.; Tornow, W. [Triangle Universities Nuclear Laboratory, P.O. Box 90308, Durham, NC 27708 (United States); Vieira, D.J. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Weisel, G.J. [Penn State Altoona, 3000 Ivyside Park, Altoona, PA 16601 (United States); Wilhelmy, J.B. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States)

    2007-08-15

    In support of the Stewardship Science Academic Alliances initiative, an experimental program has been developed at Triangle Universities Nuclear Laboratory (TUNL) to measure (n,xn) cross-sections with both in-beam and activation techniques with the goal of improving the partial cross-section database for the NNSA Stockpile Stewardship Program. First experimental efforts include excitation function measurements on {sup 235,238}U and {sup 241}Am using pulsed and monoenergetic neutron beams with E {sub n} = 5-15 MeV. Neutron-induced partial cross-sections were measured by detecting prompt {gamma} rays from the residual nuclei using various combinations of clover and planar HPGe detectors in the TUNL shielded neutron source area. Complimentary activation measurements using DC neutron beams have also been performed in open geometry in our second target area. The neutron-induced activities were measured in the TUNL low-background counting area. In this presentation, we include detailed information about the irradiation procedures and facilities and preliminary data on first measurements using this capability.

  15. Comparison of the surfaces and interfaces formed for sputter and electroless deposited gold contacts on CdZnTe

    Science.gov (United States)

    Bell, Steven J.; Baker, Mark A.; Duarte, Diana D.; Schneider, Andreas; Seller, Paul; Sellin, Paul J.; Veale, Matthew C.; Wilson, Matthew D.

    2018-01-01

    Cadmium zinc telluride (CdZnTe) is a leading sensor material for spectroscopic X/γ-ray imaging in the fields of homeland security, medical imaging, industrial analysis and astrophysics. The metal-semiconductor interface formed during contact deposition is of fundamental importance to the spectroscopic performance of the detector and is primarily determined by the deposition method. A multi-technique analysis of the metal-semiconductor interface formed by sputter and electroless deposition of gold onto (111) aligned CdZnTe is presented. Focused ion beam (FIB) cross section imaging, X-ray photoelectron spectroscopy (XPS) depth profiling and current-voltage (IV) analysis have been applied to determine the structural, chemical and electronic properties of the gold contacts. In a novel approach, principal component analysis has been employed on the XPS depth profiles to extract detailed chemical state information from different depths within the profile. It was found that electroless deposition forms a complicated, graded interface comprised of tellurium oxide, gold/gold telluride particulates, and cadmium chloride. This compared with a sharp transition from surface gold to bulk CdZnTe observed for the interface formed by sputter deposition. The electronic (IV) response for the detector with electroless deposited contacts was symmetric, but was asymmetric for the detector with sputtered gold contacts. This is due to the electroless deposition degrading the difference between the Cd- and Te-faces of the CdZnTe (111) crystal, whilst these differences are maintained for the sputter deposited gold contacts. This work represents an important step in the optimisation of the metal-semiconductor interface which currently is a limiting factor in the development of high resolution CdZnTe detectors.

  16. Implementation of a secondary-ion tritium beam by means of the associated particle technique and its test on a gold target

    Energy Technology Data Exchange (ETDEWEB)

    Policroniades, R.; Fernández-Arnáiz, J.; Murillo, G.; Moreno, E.; Villaseñor, P.; Méndez, B. [Departamento de Aceleradores, Instituto Nacional de Investigaciones Nucleares, Carr. México-Toluca S/N, Ocoyoacac, Estado de México 52750 (Mexico); Chávez, E.; Ortíz-Salazar, M.E.; Huerta, A. [Instituto de Física, Universidad Nacional Autónoma de México, A.P. 20-364, México, D.F. 01000 (Mexico); Varela-González, A. [Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, A.P. 20-364, México, D.F. 01000 (Mexico)

    2014-05-21

    In this work we present the implementation and characterization of a (secondary ion) tritium beam generated through the D(d,t)p reaction, at deuteron energies of 2.0 and 1.88 MeV, tagging the tritium ions with the associated particle technique. In order to prove its utility as a projectile for scientific applications, this beam was made to impinge on a thin gold target to observe expected elastic scattering events. - Highlights: • A new secondary ion tritium beam obtained through the D(d,t)3He reaction. • Tritium beam tagging by the associated particle technique. • A low energy Tritium beam without radiation contamination of equipment. • Tritium elastic scattering on gold.

  17. Implementation of a secondary-ion tritium beam by means of the associated particle technique and its test on a gold target

    International Nuclear Information System (INIS)

    Policroniades, R.; Fernández-Arnáiz, J.; Murillo, G.; Moreno, E.; Villaseñor, P.; Méndez, B.; Chávez, E.; Ortíz-Salazar, M.E.; Huerta, A.; Varela-González, A.

    2014-01-01

    In this work we present the implementation and characterization of a (secondary ion) tritium beam generated through the D(d,t)p reaction, at deuteron energies of 2.0 and 1.88 MeV, tagging the tritium ions with the associated particle technique. In order to prove its utility as a projectile for scientific applications, this beam was made to impinge on a thin gold target to observe expected elastic scattering events. - Highlights: • A new secondary ion tritium beam obtained through the D(d,t)3He reaction. • Tritium beam tagging by the associated particle technique. • A low energy Tritium beam without radiation contamination of equipment. • Tritium elastic scattering on gold

  18. Micro-beam X-ray fluorescence and absorption imaging techniques at the IAEA Laboratories

    International Nuclear Information System (INIS)

    Wegrzynek, Dariusz; Markowicz, A.; Bamford, S.; Chinea-Cano, E.; Bogovac, M.

    2005-01-01

    X-ray tube based, micro-beam X-ray fluorescence scanning spectrometer has been equipped with two energy dispersive X-ray detectors. The two-detector configuration allows for simultaneous collection of X-ray fluorescence (XRF) and transmitted X-ray beam signals with a spatial resolution in the range of 10-50 μm, depending on the X-ray focussing element in use. The XRF signal is collected with a standard, liquid nitrogen cooled Si(Li) detector. The X-ray beam transmitted through the sample is acquired with a thermoelectrically cooled, silicon drift (SD) detector. The data acquisition is carried out in a fully automatic way under control of the SPECTOR-LOCATOR software. The software controls the scanning procedure and X-ray spectra acquisition during the scan. The energy dispersive X-ray spectra collected at every 'pixel' are stored for off-line processing. For selected regions of interest (ROI's), the element maps are constructed and displayed on-line. The spectrometer has been used for mapping elemental distributions and for performing 2D- and 3D-tomograpic imaging of minute objects in X-ray absorption and in X-ray fluorescence mode. A unique feature of the described system is simultaneous utilization of the two detectors, Si(Li) and SD, which adds new options for quantitative analysis and data interpretation. Examples of elemental mapping and 3D tomographic imaging as well as the advanced features of the SPECTOR-LOCATOR measurement control and data acquisition software are presented in this work

  19. Physicochemical Study of Irradiated polypropylene/Organo :Modified Montmorillonite Composites by Using Electron Beam Irradiation Technique

    International Nuclear Information System (INIS)

    Hassan, M.S.

    2008-01-01

    Polypropylene/ Organo modified montmorillonite composites (PP/ OMMT) were prepared by melt blending with a twin screw extruder. The thermal properties by thermo gravimetric analysis (TGA), the dispersion of OMMT of macromolecules by X-ray diffraction (XRD), mechanical properties and the morphology by scanning electron microscopy (SEM) were investigated. The effect of electron beam irradiation on these properties was also studied. The results showed an intercalation between the silicate layers and the PP polymer matrix. The (PP/ OMMT) composites exhibit higher thermal stability and lower mechanical properties than pure polypropylene

  20. Analyses of inks and papers in historical documents through external beam PIXE techniques

    International Nuclear Information System (INIS)

    Cahill, T.A.; Kusko, B.; California Univ., Davis; Schwab, R.N.

    1981-01-01

    PIXE analyses of documents can be carried out to high senstitivty in an external beam configuration designed to protect historical materials from damage. Test runs have shown that a properbly designed system with high solid angle can operate at less than 1% of the flux necessary to cause any discoloration whatsoever on papers of the 17th and 18th centuries. The composition of these papers is suprisingly complex, yet retains distinct association with the historical period, paper source, and even the individual sheets of paper that are folded and cut to make groups of pages. Early studies are planned on historical forgeries. (orig.)