WorldWideScience

Sample records for cluster beam sputtering

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. Formation and stability of sputtered clusters

    International Nuclear Information System (INIS)

    Andersen, H.H.

    1989-01-01

    Current theory for the formation of sputtered clusters states that either atoms are sputtered individually and aggregate after having left the surface or they are sputtered as complete clusters. There is no totally sharp boundary between the two interpretations, but experimental evidence is mainly thought to favour the latter model. Both theories demand a criterion for the stability of the clusters. In computer simulations of sputtering, the idea has been to use the same interaction potential as in the lattice computations to judge the stability. More qualitatively, simple geometrical shapes have also been looked for. It is found here, that evidence for 'magic numbers' and electron parity effects in clusters have existed in the sputtering literature for a long time, making more sophisticated stability criteria necessary. The breakdown of originally sputtered metastable clusters into stable clusters gives strong support to the 'sputtered as clusters' hypothesis. (author)

  7. MD simulation of cluster formation during sputtering

    International Nuclear Information System (INIS)

    Muramoto, T.; Okai, M.; Yamashita, Y.; Yorizane, K.; Yamamura, Y.

    2001-01-01

    The cluster ejection due to cluster impact on a solid surface is studied through molecular dynamics (MD) simulations. Simulations are performed for Cu cluster impacts on the Cu(1 1 1) surface for cluster energy 100 eV/atom, and for clusters of 6, 13, 28 and 55 atoms. Interatomic interactions are described by the AMLJ-EAM potential. The vibration energy spectrum is independent of the incident cluster size and energy. This comes from the fact that sputtered clusters become stable through the successive fragmentation of nascent large sputtered clusters. The vibration energy spectra for large sputtered clusters have a peak, whose energy corresponds to the melting temperature of Cu. The exponent of the power-law fit of the abundance distribution and the total sputtering yield for the cluster impacts are higher than that for the monatomic ion impacts with the same total energy, where the exponent δ is given by Y n ∝n δ and Y n is the yield of sputtered n-atom cluster. The exponent δ follows a unified function of the total sputtering yield, which is a monotonic increase function, and it is nearly equal to δ ∼ -3 for larger yield

  8. 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

  9. 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

  10. Sputtering of neutral and ionic indium clusters

    International Nuclear Information System (INIS)

    Ma, Z.; Coon, S.R.; Calaway, W.F.; Pellin, M.J.; Gruen, D.M.; Von Nagy-Felsobuki, E.I.

    1993-01-01

    Secondary neutral and secondary ion cluster yields were measured during the sputtering of a polycrystalline indium surface by normally incident ∼4 keV Ar + ions. In the secondary neutral mass spectra, indium clusters as large as In 32 were observed. In the secondary ion mass spectra, indium clusters up to In 18 + were recorded. Cluster yields obtained from both the neutral and ion channel exhibited a power law dependence on the number of constituent atoms, n, in the cluster, with the exponents measured to be -5.6 and -4. 1, respectively. An abundance drop was observed at n=8, 15, and 16 in both the neutral and ion yield distributions suggesting that the stability of the ion (either secondary ion or photoion) plays a significant role in the observed distributions. In addition, our experiments suggest that unimolecular decomposition of the neutral cluster may also plays an important role in the measured yield distributions

  11. Cluster ion beam facilities

    International Nuclear Information System (INIS)

    Popok, V.N.; Prasalovich, S.V.; Odzhaev, V.B.; Campbell, E.E.B.

    2001-01-01

    A brief state-of-the-art review in the field of cluster-surface interactions is presented. Ionised cluster beams could become a powerful and versatile tool for the modification and processing of surfaces as an alternative to ion implantation and ion assisted deposition. The main effects of cluster-surface collisions and possible applications of cluster ion beams are discussed. The outlooks of the Cluster Implantation and Deposition Apparatus (CIDA) being developed in Guteborg University are shown

  12. XPS investigation of monatomic and cluster argon ion sputtering of tantalum pentoxide

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, Robin, E-mail: r.simpson@surrey.ac.uk [The Surface Analysis Laboratory, Department of Mechanical Engineering Sciences, University of Surrey (United Kingdom); Thermo Scientific, East Grinstead (United Kingdom); White, Richard G. [Thermo Scientific, East Grinstead (United Kingdom); Watts, John F.; Baker, Mark A. [The Surface Analysis Laboratory, Department of Mechanical Engineering Sciences, University of Surrey (United Kingdom)

    2017-05-31

    Highlights: • Ion beam induced oxide reduction from monatomic and gas cluster ion beam exposure are compared. • Lower relative level of preferential sputtering is shown in gas cluster ion beam depth profiling. • A lack of “steady state” is observed in gas cluster ion beam depth profiles of tantalum pentoxide. • Possible mechanisms behind the observed results, including temperature effects are proposed. - Abstract: In recent years, gas cluster ion beams (GCIB) have become the cutting edge of ion beam technology to sputter etch organic materials in surface analysis. However, little is currently known on the ability of argon cluster ions (Ar{sub n}{sup +}) to etch metal oxides and other technologically important inorganic compounds and no depth profiles have previously been reported. In this work, XPS depth profiles through a certified (European standard BCR-261T) 30 nm thick Ta{sub 2}O{sub 5} layer grown on Ta foil using monatomic Ar{sup +} and Ar{sub 1000}{sup +} cluster ions have been performed at different incident energies. The preferential sputtering of oxygen induced using 6 keV Ar{sub 1000}{sup +} ions is lower relative to 3 keV and 500 eV Ar{sup +} ions. Ar{sup +} ions exhibit a steady state O/Ta ratio through the bulk oxide but Ar{sub 1000}{sup +} ions show a gradual decrease in the O/Ta ratio as a function of depth. The depth resolution and etch rate is substantially better for the monatomic beam compared to the cluster beam. Higher O concentrations are observed when the underlying Ta bulk metal is sputtered for the Ar{sub 1000}{sup +} profiles compared to the Ar{sup +} profiles.

  13. 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

  14. 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.

  15. Giant metal sputtering yields induced by 20-5000 keV/atom gold clusters

    International Nuclear Information System (INIS)

    Andersen, H.H.; Brunelle, A.; Della-Negra, S.; Depauw, J.; Jacquet, D.; Le Beyec, Y.

    1997-01-01

    Very large non-linear effects have been found in cluster-induced metal sputtering over a broad projectile energy interval for the first time. Recently available cluster beams from tandem accelerators have allowed sputtering yield measurements to be made with Au 1 to Au 5 from 20 keV/atom to 5 MeV/atom. The cluster-sputtering yield maxima were found at the same total energy but not at the same energy/atom as expected. For Au 5 a yield as high as 3000 was reached at 150 keV/atom while the Au 1 yield was only 55 at the same velocity. The Sigmund-Claussen thermal spike theory, which fits published data at low energy, cannot reproduce our extended new data set. (author)

  16. 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.

  17. 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.

  18. 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

  19. 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.)

  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. Cluster beam injection

    International Nuclear Information System (INIS)

    Bottiglioni, F.; Coutant, J.; Fois, M.

    1978-01-01

    Areas of possible applications of cluster injection are discussed. The deposition inside the plasma of molecules, issued from the dissociation of the injected clusters, has been computed. Some empirical scaling laws for the penetration are given

  5. 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.

  6. Ionization of nitrogen cluster beam

    International Nuclear Information System (INIS)

    Yano, Katsuki; Be, S.H.; Enjoji, Hiroshi; Okamoto, Kosuke

    1975-01-01

    A nitrogen cluster beam (neutral particle intensity of 28.6 mAsub(eq)) is ionized by electron collisions in a Bayard-Alpert gauge type ionizer. The extraction efficiency of about 65% is obtained at an electron current of 10 mA with an energy of 50 eV. The mean cluster size produced at a pressure of 663 Torr and temperature of 77.3 K is 2x10 5 molecules per cluster. By the Coulomb repulsion force, multiply ionized cluster ions are broken up into smaller fragments and the cluster ion size reduces to one-fourth at an electron current of 15 mA. Mean neutral cluster sizes depend strongly on the initial degree of saturation PHI 0 and are 2x10 5 , 7x10 4 and 3x10 4 molecules per cluster at PHI 0 's of 0.87, 0.66 and 0.39, respectively. (auth.)

  7. Accurate argon cluster-ion sputter yields: Measured yields and effect of the sputter threshold in practical depth-profiling by x-ray photoelectron spectroscopy and secondary ion mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Cumpson, Peter J.; Portoles, Jose F.; Barlow, Anders J.; Sano, Naoko [National EPSRC XPS User' s Service (NEXUS), School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2013-09-28

    Argon Gas Cluster-Ion Beam sources are likely to become widely used on x-ray photoelectron spectroscopy and secondary ion mass spectrometry instruments in the next few years. At typical energies used for sputter depth profiling the average argon atom in the cluster has a kinetic energy comparable with the sputter threshold, meaning that for the first time in practical surface analysis a quantitative model of sputter yields near threshold is needed. We develop a simple equation based on a very simple model. Though greatly simplified it is likely to have realistic limiting behaviour and can be made useful for estimating sputter yields by fitting its three parameters to experimental data. We measure argon cluster-ion sputter yield using a quartz crystal microbalance close to the sputter threshold, for silicon dioxide, poly(methyl methacrylate), and polystyrene and (along with data for gold from the existing literature) perform least-squares fits of our new sputter yield equation to this data. The equation performs well, with smaller residuals than for earlier empirical models, but more importantly it is very easy to use in the design and quantification of sputter depth-profiling experiments.

  8. Molecular dynamics simulation of gold cluster growth during sputter deposition

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, J. W., E-mail: abraham@theo-physik.uni-kiel.de; Bonitz, M., E-mail: bonitz@theo-physik.uni-kiel.de [Institut für Theoretische Physik und Astrophysik, Christian-Albrechts-Universität zu Kiel, Leibnizstraße 15, D-24098 Kiel (Germany); Strunskus, T.; Faupel, F. [Institut für Materialwissenschaft, Lehrstuhl für Materialverbunde, Christian-Albrechts-Universität zu Kiel, Kaiserstraße 2, D-24143 Kiel (Germany)

    2016-05-14

    We present a molecular dynamics simulation scheme that we apply to study the time evolution of the self-organized growth process of metal cluster assemblies formed by sputter-deposited gold atoms on a planar surface. The simulation model incorporates the characteristics of the plasma-assisted deposition process and allows for an investigation over a wide range of deposition parameters. It is used to obtain data for the cluster properties which can directly be compared with recently published experimental data for gold on polystyrene [M. Schwartzkopf et al., ACS Appl. Mater. Interfaces 7, 13547 (2015)]. While good agreement is found between the two, the simulations additionally provide valuable time-dependent real-space data of the surface morphology, some of whose details are hidden in the reciprocal-space scattering images that were used for the experimental analysis.

  9. Design and capabilities of an experimental setup based on magnetron sputtering for formation and deposition of size-selected metal clusters on ultra-clean surfaces

    DEFF Research Database (Denmark)

    Hartmann, Hannes; Popok, Vladimir; Barke, Ingo

    2012-01-01

    The design and performance of an experimental setup utilizing a magnetron sputtering source for production of beams of ionized size-selected clusters for deposition in ultra-high vacuum is described. For the case of copper cluster formation the influence of different source parameters is studied...

  10. Angular distributions of particles sputtered from multicomponent targets with gas cluster ions

    Energy Technology Data Exchange (ETDEWEB)

    Ieshkin, A.E. [Faculty of Physics, Lomonosov Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Ermakov, Yu.A., E-mail: yuriermak@yandex.ru [Skobeltsyn Nuclear Physics Research Institute, Lomonosov Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Chernysh, V.S. [Faculty of Physics, Lomonosov Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation)

    2015-07-01

    The experimental angular distributions of atoms sputtered from polycrystalline W, Cd and Ni based alloys with 10 keV Ar cluster ions are presented. RBS was used to analyze a material deposited on a collector. It has been found that the mechanism of sputtering, connected with elastic properties of materials, has a significant influence on the angular distributions of sputtered components. The effect of non-stoichiometric sputtering at different emission angles has been found for the alloys under cluster ion bombardment. Substantial smoothing of the surface relief was observed for all targets irradiated with cluster ions.

  11. 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.

  12. 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.

  13. 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

  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. 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.

  16. Beams of mass-selected clusters: realization and first experiments

    International Nuclear Information System (INIS)

    Kamalou, O.

    2007-04-01

    The main objective of this work concerns the production of beams of mass-selected clusters of metallic and semiconductor materials. Clusters are produced in magnetron sputtering source combined with a gas aggregation chamber, cooled by liquid nitrogen circulation. Downstream of the cluster source, a Wiley-McLaren time-of-flight setup allows to select a given cluster size or a narrow size range. The pulsed mass-selected cluster ion beam is separated from the continuous neutral one by an electrostatic 90-quadrupole deflector. After the deflector, the density of the pulsed beam amounts to about 10 3 particles/cm 3 . Preliminary deposition experiments of mass-selected copper clusters with a deposition energy of about 0.5 eV/atom have ben performed on highly oriented pyrolytic graphite (HOPG) substrates, indicating that copper clusters are evidently mobile on the HOPG-surface until they reach cleavage steps, dislocation lines or other surface defects. In order to lower the cluster mobility on the HOPG-surface, we have first irradiated HOPG samples with slow highly charged ions (high dose) in order to create superficial defects. In a second step we have deposited mass-selected copper clusters on these pre-irradiated samples. The first analysis by AFM (Atomic Force Microscopy) techniques showed that the copper clusters are trapped on the defects produced by the highly charged ions. (author)

  17. Irradiation effects of Ar cluster ion beams on Si substrates

    International Nuclear Information System (INIS)

    Ishii, Masahiro; Sugahara, Gaku; Takaoka, G.H.; Yamada, Isao

    1993-01-01

    Gas-cluster ion beams can be applied to new surface modification techniques such as surface cleaning, low damage sputtering and shallow junction formation. The effects of energetic Ar cluster impacts on solid surface were studied for cluster energies of 10-30keV. Irradiation effects were studied by RBS. For Si(111) substrates, irradiated with Ar ≥500 clusters to a dose of 1x10 15 ion/cm 2 at acceleration voltage 15kV, 2x10 14 atoms/cm 2 implanted Ar atoms were detected. In this case, the energy per cluster atom was smaller than 30eV; at this energy, no significant implantation occurs in the case of monomer ions. Ar cluster implantation into Si substrates occurred due to the high energy density irradiation. (author)

  18. Dual beam organic depth profiling using large argon cluster ion beams

    Science.gov (United States)

    Holzweber, M; Shard, AG; Jungnickel, H; Luch, A; Unger, WES

    2014-01-01

    Argon cluster sputtering of an organic multilayer reference material consisting of two organic components, 4,4′-bis[N-(1-naphthyl-1-)-N-phenyl- amino]-biphenyl (NPB) and aluminium tris-(8-hydroxyquinolate) (Alq3), materials commonly used in organic light-emitting diodes industry, was carried out using time-of-flight SIMS in dual beam mode. The sample used in this study consists of a ∽400-nm-thick NPB matrix with 3-nm marker layers of Alq3 at depth of ∽50, 100, 200 and 300 nm. Argon cluster sputtering provides a constant sputter yield throughout the depth profiles, and the sputter yield volumes and depth resolution are presented for Ar-cluster sizes of 630, 820, 1000, 1250 and 1660 atoms at a kinetic energy of 2.5 keV. The effect of cluster size in this material and over this range is shown to be negligible. © 2014 The Authors. Surface and Interface Analysis published by John Wiley & Sons Ltd. PMID:25892830

  19. METI/NEDO Projects on Cluster Ion Beam Process Technology

    International Nuclear Information System (INIS)

    Yamada, Isao; Matsuo, Jiro; Toyoda, Noriaki

    2003-01-01

    Since the initial study of gas cluster ion beams (GCIB) was started in the Ion Beam Engineering Experimental Laboratory of Kyoto University, more than 15 years have passed. Some of the results of that study have already been applied for industrial use. Unique characteristics of gas cluster ion bombardment have been found to offer potential for various other industrial applications. The impact of an accelerated cluster ion upon a target surface imparts very high energy densities into the impact area and produces non-linear effects that are not associated with the impacts of atomic ions. Among prospective applications for these effects are included shallow ion implantation, high rate sputtering, surface cleaning and smoothing, and low temperature thin film formation

  20. Dependence of energy per molecule on sputtering yields with reactive gas cluster ions

    International Nuclear Information System (INIS)

    Toyoda, Noriaki; Yamada, Isao

    2010-01-01

    Gas cluster ions show dense energy deposition on a target surface, which result in the enhancement of chemical reactions. In reactive sputtering with gas cluster ions, the energy per atom or molecule plays an important role. In this study, the average cluster size (N, the number of atoms or molecules in a cluster ion) was controlled; thereby the dependences of the energy per molecule on the sputtering yields of carbon by CO 2 cluster ions and that of Si by SF 6 /Ar mixed gas cluster ions were investigated. Large CO 2 cluster ions with energy per molecule of 1 eV showed high reactive sputtering yield of an amorphous carbon film. However, these ions did not cause the formation of large craters on a graphite surface. It is possible to achieve very low damage etching by controlling the energy per molecule of reactive cluster ions. Further, in the case of SF 6 /Ar mixed cluster ions, it was found that reactive sputtering was enhanced when a small amount of SF 6 gas (∼10%) was mixed with Ar. The reactive sputtering yield of Si by one SF 6 molecule linearly increased with the energy per molecule.

  1. 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

  2. The influence of landing points on the sputtering of mono-crystal solids due to cluster impacting

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Guo-jian; Li, Xiao-chun; Xu, Qian; Yang, Zhong-shi, E-mail: zsyang@ipp.ac.cn; Luo, Guang-nan, E-mail: gnluo@ipp.ac.cn

    2017-01-15

    The mechanism of sputtering due to cluster impacting which has been widely studied is an important but unsolved problem. In present research, we discuss the effect of the landing point on the sputtering with the method of molecular dynamics. The results show that the landing points play significant roles on sputter yield when the temperature of target is low. Specific landing points can cause particular sputtering patterns which lead to different sputtering yield and moving directions of sputtered atoms. The mechanism of this phenomenon is that specific landing keeps symmetries and anisotropies of target lattice, which influence the sputtering yield.

  3. 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.

  4. 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.

  5. Surface processing with ionized cluster beams: computer simulation

    International Nuclear Information System (INIS)

    Insepov, Z.; Yamada, I.

    1999-01-01

    Molecular Dynamics (MD) and Monte Carlo (MC) models of energetic gas cluster irradiation of a solid surface have been developed to investigate the phenomena of crater formation, sputtering, surface treatment, and the material hardness evaluation by irradiation with cluster ions. Theoretical estimation of crater dimensions formed with Ar gas cluster ion irradiation of different substrates, based on hydrodynamics and MD simulation, are presented. The atomic scale shock waves arising from cluster impact were obtained by calculating the pressure, temperature and mass-velocity of the target atoms. The crater depth is given as a unique 1/3 dependence on the cluster energy and on the cold material Brinell hardness number (BHN). A new 'true material hardness' scale which can be very useful for example for thin film coatings deposited on a soft substrate, is defined. This finding could be used as a new technique for measuring of a material hardness. Evolution of surface morphology under cluster ion irradiation was described by the surface relaxation equation which contains a term of crater formation at cluster impact. The formation of ripples on a surface irradiated with oblique cluster ion beams was predicted. MD and MC models of Decaborane ion (B 10 H 14 ) implantation into Si and the following rapid thermal annealing (RTA) have been developed

  6. 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)

  7. 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.

  8. 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)

  9. Investigation of energy thresholds of atomic and cluster sputtering of some elements under ion bombardment

    CERN Document Server

    Atabaev, B G; Lifanova, L F

    2002-01-01

    Threshold energies of sputtering of negative cluster ions from the Si(111) surface were measured at bombardment by Cs sup + , Rb sup + , and Na sup + ions with energy of 0.1-3.0 keV. These results are compared with the calculations of the similar thresholds by Bohdansky etc. formulas (3) for clusters Si sub n sup - and Cu sub n sup - with n=(1-5) and also for B, C, Al, Si, Fe, Cu atoms. Threshold energies of sputtering for the above elements were also estimated using the data from (5). Satisfactory agreement between the experimental and theoretical results was obtained. (author)

  10. 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

  11. 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

  12. 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

  13. 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

  14. Supersonic bare metal cluster beams

    International Nuclear Information System (INIS)

    Smalley, R.E.

    1991-01-01

    Progress continued this past year on two principal fronts in the study of bare metal clusters: photoelectron spectroscopy of mass selected negative ions, and surface chemisorption of cluster ions levitated in a superconducting magnet as monitored by fourier transform ion cyclotron resonance

  15. 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.

  16. 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.

  17. Kinetic energy distributions of sputtered neutral aluminum clusters: Al--Al6

    International Nuclear Information System (INIS)

    Coon, S.R.; Calaway, W.F.; Pellin, M.J.; Curlee, G.A.; White, J.M.

    1992-01-01

    Neutral aluminum clusters sputtered from polycrystalline aluminum were analyzed by laser postionization time-of-flight (TOF) mass spectrometry. The kinetic energy distributions of Al through Al 6 were measured by a neutrals time-of-flight technique. The interpretation of laser postionization TOF data to extract velocity and energy distributions is presented. The aluminum cluster distributions are qualitatively similar to previous copper cluster distribution measurements from our laboratory. In contrast to the steep high energy tails predicted by the single- or multiple- collision models, the measured cluster distributions have high energy power law dependences in the range of E -3 to E -4.5 . Correlated collision models may explain the substantial abundance of energetic clusters that are observed in these experiments. Possible influences of cluster fragmentation on the distributions are discussed

  18. 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.

  19. Indium tin oxide surface smoothing by gas cluster ion beam

    CERN Document Server

    Song, J H; Choi, W K

    2002-01-01

    CO sub 2 cluster ions are irradiated at the acceleration voltage of 25 kV to remove hillocks on indium tin oxide (ITO) surfaces and thus to attain highly smooth surfaces. CO sub 2 monomer ions are also bombarded on the ITO surfaces at the same acceleration voltage to compare sputtering phenomena. From the atomic force microscope results, the irradiation of monomer ions makes the hillocks sharper and the surfaces rougher from 1.31 to 1.6 nm in roughness. On the other hand, the irradiation of CO sub 2 cluster ions reduces the height of hillocks and planarize the ITO surfaces as smooth as 0.92 nm in roughness. This discrepancy could be explained by large lateral sputtering yield of the cluster ions and re-deposition of sputtered particles by the impact of the cluster ions on surfaces.

  20. Detection of high mass cluster ions sputtered from Bi surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, A; Hewitt, R W; Slusser, G J; Baitinger, W E; Cooks, R G; Winograd, N [Purdue Univ., Lafayette, Ind. (USA). Dept. of Chemistry; Delgass, W N [Purdue Univ., Lafayette, Ind. (USA); Varon, A; Devant, G [Societe RIBER, 92 - Rueil-Malmaison (France)

    1976-12-01

    The technique of secondary ion mass spectrometry (SIMS) has been employed to detect Bi/sup 3 +/ ions and associated oxides Bi/sub 3/Osub(x)sup(+)(x=1 to 4) from a Bi foil. Using a 3 keV Ar/sup +/ ion primary beam of 5x10/sup -7/ A/cm/sup 2/, mass resolution to nearly 700 with the requisite sensitivity has been achieved. The Bi surface was also monitored by X-ray photoelectron spectroscopy (XPS or ESCA). The presence of a weak O 1s peak at 532.7 eV and a strong SIMS Bi/sup 3 +/ peak is interpreted to mean that the oxygen is weakly incorporated into the Bi lattice without disrupting metal-metal bonds.

  1. 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)

  2. 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

  3. Production of Au clusters by plasma gas condensation and their incorporation in oxide matrixes by sputtering

    Science.gov (United States)

    Figueiredo, N. M.; Serra, R.; Manninen, N. K.; Cavaleiro, A.

    2018-05-01

    Gold clusters were produced by plasma gas condensation method and studied in great detail for the first time. The influence of argon flow, discharge power applied to the Au target and aggregation chamber length on the size distribution and deposition rate of Au clusters was evaluated. Au clusters with sizes between 5 and 65 nm were deposited with varying deposition rates and size dispersion curves. Nanocomposite Au-TiO2 and Au-Al2O3 coatings were then deposited by alternating sputtering. These coatings were hydrophobic and showed strong colorations due to the surface plasmon resonance effect. By simulating the optical properties of the nanocomposites it was possible to identify each individual contribution to the overall surface plasmon resonance signal. These coatings show great potential to be used as high performance localized surface plasmon resonance sensors or as robust self-cleaning decorative protective layers. The hybrid method used for depositing the nanocomposites offers several advantages over co-sputtering or thermal evaporation processes, since a broader range of particle sizes can be obtained (up to tens of nanometers) without the application of any thermal annealing treatments and the properties of clusters and matrix can be controlled separately.

  4. 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

  5. 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

  6. First high energy hydrogen cluster beams

    International Nuclear Information System (INIS)

    Gaillard, M.J.; Genre, R.; Hadinger, G.; Martin, J.

    1993-03-01

    The hydrogen cluster accelerator of the Institut de Physique Nucleaire de Lyon (IPN Lyon) has been upgraded by adding a Variable Energy Post-accelerator of RFQ type (VERFQ). This operation has been performed in the frame of a collaboration between KfK Karlsruhe, IAP Frankfurt and IPN Lyon. The facility has been designed to deliver beams of mass selected Hn + clusters, n chosen between 3 and 49, in the energy range 65-100 keV/u. For the first time, hydrogen clusters have been accelerated at energies as high as 2 MeV. This facility opens new fields for experiments which will greatly benefit from a velocity range never available until now for such exotic projectiles. (author) 13 refs.; 1 fig

  7. Molecular dynamics simulations of sputtering of organic overlayers by slow, large clusters

    International Nuclear Information System (INIS)

    Rzeznik, L.; Czerwinski, B.; Garrison, B.J.; Winograd, N.; Postawa, Z.

    2008-01-01

    The ion-stimulated desorption of organic molecules by impact of large and slow clusters is examined using molecular dynamics (MDs) computer simulations. The investigated system, represented by a monolayer of benzene deposited on Ag{1 1 1}, is irradiated with projectiles composed of thousands of noble gas atoms having a kinetic energy of 0.1-20 eV/atom. The sputtering yield of molecular species and the kinetic energy distributions are analyzed and compared to the results obtain for PS4 overlayer. The simulations demonstrate quite clearly that the physics of ejection by large and slow clusters is distinct from the ejection events stimulated by the popular SIMS clusters, like C 60 , Au 3 and SF 5 at tens of keV energies.

  8. 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

  9. 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.

  10. 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...

  11. 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.

  12. 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

  13. Molecular dynamics simulations with electronic stopping can reproduce experimental sputtering yields of metals impacted by large cluster ions

    Science.gov (United States)

    Tian, Jiting; Zhou, Wei; Feng, Qijie; Zheng, Jian

    2018-03-01

    An unsolved problem in research of sputtering from metals induced by energetic large cluster ions is that molecular dynamics (MD) simulations often produce sputtering yields much higher than experimental results. Different from the previous simulations considering only elastic atomic interactions (nuclear stopping), here we incorporate inelastic electrons-atoms interactions (electronic stopping, ES) into MD simulations using a friction model. In this way we have simulated continuous 45° impacts of 10-20 keV C60 on a Ag(111) surface, and found that the calculated sputtering yields can be very close to the experimental results when the model parameter is appropriately assigned. Conversely, when we ignore the effect of ES, the yields are much higher, just like the previous studies. We further expand our research to the sputtering of Au induced by continuous keV C60 or Ar100 bombardments, and obtain quite similar results. Our study indicates that the gap between the experimental and the simulated sputtering yields is probably induced by the ignorance of ES in the simulations, and that a careful treatment of this issue is important for simulations of cluster-ion-induced sputtering, especially for those aiming to compare with experiments.

  14. 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

  15. 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.

  16. Dependence of surface smoothing, sputtering and etching phenomena on cluster ion dosage

    CERN Document Server

    Song, J H; Choi, W K

    2002-01-01

    The dependence of surface smoothing and sputtering phenomena of Si (1 0 0) solid surfaces irradiated by CO sub 2 cluster ions on cluster-ion dosage was investigated using an atomic force microscope. The flux and total ion dosage of impinging cluster ions at the acceleration voltage of 50 kV were fixed at 10 sup 9 ions/cm sup 2 s and were scanned from 5x10 sup 1 sup 0 to 5x10 sup 1 sup 3 ions/cm sup 2 , respectively. The density of hillocks induced by cluster ion impact was gradually increased with the dosage up to 5x10 sup 1 sup 1 ions/cm sup 2 , which caused that the irradiated surface became rough from 0.4 to 1.24 nm in root-mean-square roughness (sigma sub r sub m sub s). At the boundary of the ion dosage of 10 sup 1 sup 2 ions/cm sup 2 , the density of the induced hillocks was decreased and sigma sub r sub m sub s was about 1.21 nm, not being deteriorated further. At the dosage of 5x10 sup 1 sup 3 ions/cm sup 2 , the induced hillocks completely disappeared and the surface became very flat as much as sigma...

  17. From atoms to layers: in situ gold cluster growth kinetics during sputter deposition

    Science.gov (United States)

    Schwartzkopf, Matthias; Buffet, Adeline; Körstgens, Volker; Metwalli, Ezzeldin; Schlage, Kai; Benecke, Gunthard; Perlich, Jan; Rawolle, Monika; Rothkirch, André; Heidmann, Berit; Herzog, Gerd; Müller-Buschbaum, Peter; Röhlsberger, Ralf; Gehrke, Rainer; Stribeck, Norbert; Roth, Stephan V.

    2013-05-01

    The adjustment of size-dependent catalytic, electrical and optical properties of gold cluster assemblies is a very significant issue in modern applied nanotechnology. We present a real-time investigation of the growth kinetics of gold nanostructures from small nuclei to a complete gold layer during magnetron sputter deposition with high time resolution by means of in situ microbeam grazing incidence small-angle X-ray scattering (μGISAXS). We specify the four-stage growth including their thresholds with sub-monolayer resolution and identify phase transitions monitored in Yoneda intensity as a material-specific characteristic. An innovative and flexible geometrical model enables the extraction of morphological real space parameters, such as cluster size and shape, correlation distance, layer porosity and surface coverage, directly from reciprocal space scattering data. This approach enables a large variety of future investigations of the influence of different process parameters on the thin metal film morphology. Furthermore, our study allows for deducing the wetting behavior of gold cluster films on solid substrates and provides a better understanding of the growth kinetics in general, which is essential for optimization of manufacturing parameters, saving energy and resources.The adjustment of size-dependent catalytic, electrical and optical properties of gold cluster assemblies is a very significant issue in modern applied nanotechnology. We present a real-time investigation of the growth kinetics of gold nanostructures from small nuclei to a complete gold layer during magnetron sputter deposition with high time resolution by means of in situ microbeam grazing incidence small-angle X-ray scattering (μGISAXS). We specify the four-stage growth including their thresholds with sub-monolayer resolution and identify phase transitions monitored in Yoneda intensity as a material-specific characteristic. An innovative and flexible geometrical model enables the extraction

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.)

  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. 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

  5. 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

  6. Production and characterization of supersonic carbon cluster beams

    International Nuclear Information System (INIS)

    Rohlfing, E.A.; Cox, D.M.; Kaldor, A.

    1984-01-01

    Laser vaporization of a substrate within the throat of a pulsed nozzle is used to generate a supersonic beam of carbon clusters. The neutral cluster beam is probed downstream by UV laser photoionization with time-of-flight mass analysis of the resulting photoions. Using graphite as the substrate, carbon clusters C/sub n/ for n = 1--190 have been produced having a distinctly bimodal cluster size distribution: (i) Both even and odd clusters for C/sub n/, 1 + /sub n/ signals are interpreted on the basis of cluster formation and stability arguments. Ionizing laser power dependences taken at several different photon energies are used to roughly bracket the carbon cluster ionization potentials, and, at high laser intensity, to observe the onset of multiphoton fragmentation. By treating the graphite rod with KOH, a greatly altered carbon cluster distribution with mixed carbon/potassium clusters of formula K 2 C/sub 2n/ is produced

  7. AN INVESTIGATION OF THE BEAM MONITOR FOR THE CLUSTER KLYSTRON

    International Nuclear Information System (INIS)

    ZHAO, Y.

    2001-01-01

    The cluster klystron project required a beam monitor to check the quality of the hollow beam shape. Since the power density of the beam is very large, a common phosphorescent screen doesn't work. We investigated varies types of monitors. The related problems were also discussed

  8. Low-energy irradiation effects of gas cluster ion beams

    International Nuclear Information System (INIS)

    Houzumi, Shingo; Takeshima, Keigo; Mochiji, Kozo; Toyoda, Noriaki; Yamada, Isao

    2007-01-01

    A cluster-ion irradiation system with cluster-size selection has been developed to study the effects of the cluster size for surface processes using cluster ions. A permanent magnet with a magnetic field of 1.2 T is installed for size separation of large cluster ions. Trace formations at HOPG surface by the irradiation with size-selected Ar-cluster ions under acceleration energy of 30 keV were investigated by a scanning tunneling microscopy. Generation behavior of the crater-like traces is strongly affected by the number of constituent atoms (cluster size) of the irradiating cluster ion. When the incident cluster ion is composed of 100-3000 atoms, crater-like traces are observed on the irradiated surfaces. In contrast, such traces are not observed at all with the irradiation of the cluster-ions composed of over 5000 atoms. Such the behavior is discussed on the basis of the kinetic energy per constituent atom of the cluster ion. To study GCIB irradiation effects against macromolecule, GCIB was irradiated on DNA molecules absorbed on graphite surface. By the GCIB irradiation, much more DNA molecules was sputtered away as compared with the monomer-ion irradiation. (author)

  9. 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)

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. Smoothing of ZnO films by gas cluster ion beam

    International Nuclear Information System (INIS)

    Chen, H.; Liu, S.W.; Wang, X.M.; Iliev, M.N.; Chen, C.L.; Yu, X.K.; Liu, J.R.; Ma, K.; Chu, W.K.

    2005-01-01

    Planarization of wide-band-gap semiconductor ZnO surface is crucial for thin-film device performance. In this study, the rough initial surfaces of ZnO films deposited by r.f. magnetron sputtering on Si substrates were smoothed by gas cluster ion beams. AFM measurements show that the average surface roughness (R a ) of the ZnO films could be reduced considerably from 16.1 nm to 0.9 nm. Raman spectroscopy was used to monitor the structure of both the as-grown and the smoothed ZnO films. Rutherford back-scattering in combination with channeling effect was used to study the damage production induced by the cluster bombardment

  18. Properties of an ionised-cluster beam from a vaporised-cluster ion source

    International Nuclear Information System (INIS)

    Takagi, T.; Yamada, I.; Sasaki, A.

    1978-01-01

    A new type of ion source vaporised-metal cluster ion source, has been developed for deposition and epitaxy. A cluster consisting of 10 2 to 10 3 atoms coupled loosely together is formed by adiabatic expansion ejecting the vapour of materials into a high-vacuum region through the nozzle of a heated crucible. The clusters are ionised by electron bombardment and accelerated with neutral clusters toward a substrate. In this paper, mechanisms of cluster formation experimental results of the cluster size (atoms/cluster) and its distribution, and characteristics of the cluster ion beams are reported. The size is calculated from the kinetic equation E = (1/2)mNVsub(ej) 2 , where E is the cluster beam energy, Vsub(ej) is the ejection velocity, m is the mass of atom and N is the cluster size. The energy and the velocity of the cluster are measured by an electrostatic 127 0 energy analyser and a rotating disc system, respectively. The cluster size obtained for Ag is about 5 x 10 2 to 2 x 10 3 atoms. The retarding potential method is used to confirm the results for Ag. The same dependence on cluster size for metals such as Ag, Cu and Pb has been obtained in previous experiments. In the cluster state the cluster ion beam is easily produced by electron bombardment. About 50% of ionised clusters are obtained under typical operation conditions, because of the large ionisation cross sections of the clusters. To obtain a uniform spatial distribution, the ionising electrode system is also discussed. The new techniques are termed ionised-cluster beam deposition (ICBD) and epitaxy (ICBE). (author)

  19. 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)

  20. 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.

  1. Study of Si wafer surfaces irradiated by gas cluster ion beams

    International Nuclear Information System (INIS)

    Isogai, H.; Toyoda, E.; Senda, T.; Izunome, K.; Kashima, K.; Toyoda, N.; Yamada, I.

    2007-01-01

    The surface structures of Si (1 0 0) wafers subjected to gas cluster ion beam (GCIB) irradiation have been analyzed by cross-sectional transmission electron microscopy (XTEM) and atomic force microscopy (AFM). GCIB irradiation is a promising technique for both precise surface etching and planarization of Si wafers. However, it is very important to understand the crystalline structure of Si wafers after GCIB irradiation. An Ar-GCIB used for the physically sputtering of Si atoms and a SF 6 -GCIB used for the chemical etching of the Si surface are also analyzed. The GCIB irradiation increases the surface roughness of the wafers, and amorphous Si layers are formed on the wafer surface. However, when the Si wafers are annealed in hydrogen at a high temperature after the GCIB irradiation, the surface roughness decreases to the same level as that before the irradiation. Moreover, the amorphous Si layers disappear completely

  2. Ion beam induced nanosized Ag metal clusters in glass

    International Nuclear Information System (INIS)

    Mahnke, H.-E.; Schattat, B.; Schubert-Bischoff, P.; Novakovic, N.

    2006-01-01

    Silver metal clusters have been formed in soda lime glass by high-energy heavy-ion irradiation at ISL. The metal cluster formation was detected with X-ray absorption spectroscopy (EXAFS) in fluorescence mode, and the shape of the clusters was imaged with transmission electron microscopy. While annealing in reducing atmosphere alone, leads to the formation of metal clusters in Ag-containing glasses, where the Ag was introduced by ion-exchange, such clusters are not very uniform in size and are randomly distributed over the Ag-containing glass volume. Irradiation with 600-MeV Au ions followed by annealing, however, results in clusters more uniform in size and arranged in chains parallel to the direction of the ion beam

  3. 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

  4. Gas cluster ion beam equipments for industrial applications

    International Nuclear Information System (INIS)

    Matsuo, J.; Takaoka, G.H.; Yamada, I.

    1995-01-01

    30 keV and 200 keV gas cluster ion beam equipments have been developed for industrial applications. A gas cluster source with a non-cooled nozzle was used for both the equipments. Sufficient monomer ion suppression was achieved by using an ExB filter and chromatic lenses mass filter with low extraction voltage. These equipments are suitable to be used for low-damage surface treatment of metals, insulators and semiconductors without heavy metal contamination. (orig.)

  5. 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.

  6. 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

  7. Chemical degradation of selected Zn-based corrosion products induced by C{sub 60} cluster, Ar cluster and Ar{sup +} ion sputtering in the focus of X-ray photoelectron spectroscopy (XPS)

    Energy Technology Data Exchange (ETDEWEB)

    Steinberger, R., E-mail: roland.steinberger@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterization, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Sicking, J., E-mail: jens.sicking@bayer.com [Bayer AG, Engineering & Technology, Applied Physics, Chempark Building E 41, 51368 Leverkusen (Germany); Weise, J., E-mail: juliane.weise@physik.tu-freiberg.de [Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09599 Freiberg (Germany); Duchoslav, J., E-mail: jiri.duchoslav@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterization, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Greunz, T., E-mail: theresia.greunz@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterization, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Meyer, D.C., E-mail: Dirk-Carl.Meyer@physik.tu-freiberg.de [Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09599 Freiberg (Germany); Stifter, D., E-mail: david.stifter@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterization, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria)

    2017-05-01

    Highlights: • XPS investigations for various sputter concepts on Zn-based corrosions products. • Direct comparison of induced chemical damage for ion and cluster sputtering. • Azimuthal rotation or heavy projectile bombardment was not found to be beneficial. • Ar cluster etching is rated as unsuitable for surface cleaning or depth profiling. • C{sub 60} and Ar{sup +} are applicable for sputtering when degradation is carefully considered. - Abstract: Monoatomic ion sputtering is a common concept for surface sensitive analysis methods to clean surfaces prior investigation or to obtain information from deeper regions. However, severe damage of the materials – linked to preferential sputtering, ion implantation, atomic mixing and in worst case chemical degradation – can affect the validity of the analysis. Hence, the impact of C{sub 60} cluster etching, furthermore, of Ar{sup +} ion bombardment with and without azimuthal sample rotation and also the application of heavy projectiles (Xe{sup +} ions) was investigated to find a concept, which is less destructive or with less critical influence on the chemical nature of the investigated materials. In this work the focus is set on hydrozincite and zinc oxide, two common corrosion products of Zn-based coatings. As a main point, all the obtained results from (i) Ar{sup +} ion, (ii) Ar cluster, and (iii) C{sub 60} cluster etching on the degradation kinetics of hydrozincite were compared with respect to the reached sputter depth. In addition, the sputter rate of all three methods was experimentally determined for ZnO. In total, fully non-destructive conditions could not be found, but valuable knowledge on the type and rate of degradation, which is essential to choose the most suited sputter concept.

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. Cluster ion formation during sputtering processes: a complementary investigation by ToF-SIMS and plasma ion mass spectrometry

    International Nuclear Information System (INIS)

    Welzel, T; Ellmer, K; Mändl, S

    2014-01-01

    Plasma ion mass spectrometry using a plasma process monitor (PPM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) have been complementarily employed to investigate the sputtering and ion formation processes of Al-doped zinc oxide. By comparing the mass spectra, insights on ion formation and relative cross-sections have been obtained: positive ions as measured during magnetron sputtering by PPM are originating from the plasma while those in SIMS start at the surface leading to large differences in the mass spectra. In contrast, negative ions originating at the surface will be accelerated through the plasma sheath. They arrive at the PPM after traversing the plasma nearly collisionless as seen from the rather similar spectra. Hence, it is possible to combine the high mass resolution of ToF-SIMS to obtain insight for separating cluster ions, e.g. Zn x and ZnO y , and the energy resolution of PPM to find fragmentation patterns for negative ions. While the ion formation processes during both experiments can be assumed to be similar, differences may arise due to the lower volume probed by SIMS. In the latter case, there is a chance of small target inhomogeneities being able to be enhanced and lower surface temperatures leading to less outgassing and, thus, retention of volatile compounds. (paper)

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

    International Nuclear Information System (INIS)

    Bettini, Luca Giacomo; Bardizza, Giorgio; Podestà, Alessandro; Milani, Paolo; Piseri, Paolo

    2013-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-02-15

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

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

    Science.gov (United States)

    Bettini, Luca Giacomo; Bardizza, Giorgio; Podestà, Alessandro; Milani, Paolo; Piseri, Paolo

    2013-02-01

    Nanostructured porous films of carbon with density of about 0.5 g/cm3 and 200 nm thickness were deposited at room temperature by supersonic cluster beam deposition (SCBD) from carbon clusters formed in the gas phase. Carbon film surface topography, determined by atomic force microscopy, reveals a surface roughness of 16 nm and a granular morphology arising from the low kinetic energy ballistic deposition regime. The material is characterized by a highly disordered carbon structure with predominant sp2 hybridization as evidenced by Raman spectroscopy. The interface properties of nanostructured carbon electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy employing KOH 1 M solution as aqueous electrolyte. An increase of the double layer capacitance is observed when the electrodes are heat treated in air or when a nanostructured nickel layer deposited by SCBD on top of a sputter deposited film of the same metal is employed as a current collector instead of a plain metallic film. This enhancement is consistent with an improved charge injection in the active material and is ascribed to the modification of the electrical contact at the interface between the carbon and the metal current collector. Specific capacitance values up to 120 F/g have been measured for the electrodes with nanostructured metal/carbon interface.

  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. Anomalous foreshock field-aligned beams observed by Cluster

    Directory of Open Access Journals (Sweden)

    K. Meziane

    2011-10-01

    Full Text Available We report occasional observations of two simultaneously distinct ion foreshock components recorded by the Cluster spacecraft upstream of the Earth's bow shock. In most occurrences, the lower-energy population originates as a field-aligned beam (FAB associated with quasi-perpendicular regions, which loses energy as the IMF rotates into oblique geometries. A second beam, with energies in excess of ~10 keV, appears sometimes in association with the onset of ultra-low frequency (ULF waves, and sometimes ahead of the appearance of the latter. Measurements from the mass spectrometer indicate that both beams consist of protons. While the lower-speed beam is well-accounted for by a known reflection mechanism, the non-radial IMF orientations as well as other arguments seem to rule out magnetosheath or magnetospheric sources for the higher energy component. The wave characteristics are typical of the oblique foreshock and we have found that they are in cyclotron-resonance with the low speed beam (FAB. These observations constitute a theoretical challenge since conventional mechanisms described in the literature cannot account for the production of beams at two different energies.

  4. 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

  5. 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

  6. 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).

  7. 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.

  8. 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

  9. 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

  10. Non-linear sputtering effects induced by MeV energy gold clusters

    International Nuclear Information System (INIS)

    Boussofiane-Baudin, K.; Brunelle, A.; Chaurand, P.; Della-Negra, S.; Depauw, J.; Le Beyec, Y.; Hakansson, P.

    1993-09-01

    Gold clusters Au n + with 1 < n ≤ 4, accelerated to MeV energies at the Orsay tandem accelerator, have been used to induce secondary ion emission from the surface of thin organic and inorganic films. A non-linear enhancement of the secondary ion yields is observed when cluster impacts are compared to single atom impacts at the same velocity. It has been shown that the collective effects propagate in the solid over a depth larger than 2000 A. The equilibrium charge state of cluster constituents after their passage through a thin carbon foil (1000 A) has been measured. The mean value for the cluster constituents is the same as for single atoms at the same velocity. (authors). 41 refs., 8 figs., 1 tab

  11. 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.

  12. 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.)

  13. 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

  14. 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

  15. Case Study of Ion Beams Observed By Cluster At Perigee

    Science.gov (United States)

    Sergeev, V.; Sauvaud, J.-A.; Perigee Beam Team

    During substorms the short beams of ions in the keV-to-tens keV energy range are injected into the auroral flux tubes from the magnetotail (sometimes extending up to >100 keV energy) carrying the information on the source distance, scale-size and temporal history of plasma acceleration. We present observations with the CLUSTER crossing inward the auroral zone flux tubes at ~4Re distance near its perigee during the substorm activity on February 14, 2001. The ion beams cover the same region (poleward half) of the auroral oval where the low-energy ions are extracted from the ionosphere, and where the small-scale transient transverse Alfven waves are observed which carry predominantly the downward parallel Poynting flux into the ionosphere. The multiple beams were basically confirmed to be the transient effects, although some effects including the (spatial) velocity filter and the parallel electric fields (im- posed by quasineutrality requirement) may complicate the interpretation. The gener- ation region of ion beams is not limited to most poleward, newly-reconnected flux tubes; the beam generation region could extend across magnetic field inward by as much as >100km (if mapped to the ionosphere). Surprising variety of injection dis- tances observed nearly simultaneously (ranging between >60 Re and ~10 Re) have been inferred when using the full available energy and time resolution, with shorter injection distances be possibly associated with the flow braking process. The beam multiplicity often displays the apparent ~3 min quasiperiodicity inherent to the basic dissipation process, it was not yet explained by any substorm theory.

  16. Growth of Ge films by cluster beam deposition

    CERN Document Server

    Xu, J L; Feng, J Y

    2002-01-01

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

  17. Imaging with Mass Spectrometry: A SIMS and VUV-Photoionization Study of Ion-Sputtered Atoms and Clusters from GaAs and Au

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Lynelle; Zhou, Jia; Wilson, Kevin R.; Leone, Stephen R.; Ahmed, Musahid

    2008-12-05

    A new mass spectrometry surface imaging method is presented in which ion-sputtered neutrals are postionized by wavelength-tunable vacuum ultraviolet (VUV) light from a synchrotron source. Mass spectra and signal counts of the photoionized neutrals from GaAs (100) and Au are compared to those of the secondary ions. While clusters larger than dimers are more efficiently detected as secondary ions, certain species, such as As2, Au and Au2, are more efficiently detected through the neutral channel. Continuously tuning the photon wavelength allows photoionization efficiency (PIE) curves to be obtained for sputtered Asm (m=1,2) and Aun (n=1-4). From the observed ionization thresholds, sputtered neutral As and Au show no clear evidence of electronic excitation, while neutral clusters have photoionization onsets shifted to lower energies by ~;;0.3 eV. These shifts are attributed to unresolved vibrational and rotational excitations. High-spatial resolution chemical imaging with synchrotron VUV postionization is demonstrated at two different photon energies using a copper TEM grid embedded in indium. The resulting images are used to illustrate the use of tunable VUV light for verifying mass peak assignments by exploiting the unique wavelength-dependent PIE of each sputtered neutral species. This capability is valuable for identifying compounds when imaging chemically complex systems with mass spectrometry-based techniques.

  18. 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)

  19. Magnetron sputtering cluster apparatus for formation and deposition of size-selected metal nanoparticles

    DEFF Research Database (Denmark)

    Hanif, Muhammad; Popok, Vladimir

    2015-01-01

    selection is achieved using an electrostatic quadrupole mass selector. The deposited silver clusters are studied using atomic force microscopy. The height distributions show typical relative standard size deviation of 9-13% for given sizes in the range between 5-23 nm. Thus, the apparatus demonstrates good...... capability in formation of supported size-selected metal nanoparticles with controllable coverage for various practical applications....

  20. 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.

  1. The electron beam diagnostic of the clustered supersonic nitrogen jets

    Science.gov (United States)

    Avtaeva, S. V.; Yakovleva, T. S.; Kalyada, V. V.; Zarvin, A. E.

    2017-11-01

    Axial and radial distributions of the rotational temperature and density of N2 molecules in supersonic nitrogen jets formed with conic nozzles (critical diameters dcr of 0.17 and 0.21 mm) were studied using the electron beam fluorescence technique at stagnation pressures P0 of 0.1-0.6 MPa. A rotational temperature Tr , equaling a gas temperature Tg owing to fast RT relaxation, was obtained using the rotational line relative intensity distribution in (0-1) vibrational band of the N2 first negative system. Gas density profiles in the jets were obtained using the integral intensity of the band. It is found, Tr at the nozzle outlet is of the order of a few tens of Kelvin and at further expansion Tr drops up to 15-20K at distance of (100-200) dcr . The gas temperature and density distributions in the studied supersonic nitrogen jets are not similar to the isentropic distributions. It is shown that the lower is the stagnation pressure the faster the gas density and temperature decrease with distance from the nozzle. Increase in P0 leads to elevating Tg in the jets. A reason for this effect may be cluster formation in the jets. Estimations of cluster mean sizes in the jets using Hagena’s parameter show presence of large clusters (M≥200) at P0 = 0.4-0.6 MPa.

  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. 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

  4. 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.

  5. 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.

  6. 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.

  7. Atomic size effect on the formation of ionized cluster beam epitaxy in Lennard-Jones systems

    International Nuclear Information System (INIS)

    Hsieh Horngming; Averback, R.S.

    1991-01-01

    Ionized cluster beam deposition is studied by molecular dynamics simulations in which the atomic size of incident cluster atoms is different from the size of substrate atoms. Lennard-Jones interatomic potentials are used for the two-component system. The results provide the morphologies of the overlayers for various atomic sizes and are compared to simulation results of molecular beam epitaxy. (orig.)

  8. Description of a laser vaporization source and a supersonic cluster beam apparatus

    International Nuclear Information System (INIS)

    Doverstaal, M.; Lindgren, B.; Sassenberg, U.; Yu, H.

    1993-11-01

    Laser vaporization of an appropriate target and recent developments in molecular beam technology have now made it possible to produce supersonic cluster beams of virtually any element in the periodic table. This paper describes the design and principles of a cluster source combined with a time of flight mass spectrometer built for reaction experiments and spectroscopic investigations at Stockholm University

  9. 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.

  10. 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.

  11. 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.

  12. 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....

  13. 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.)

  14. Observations on Si-based micro-clusters embedded in TaN thin film deposited by co-sputtering with oxygen contamination

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Mi [Beamline Division, Pohang Accelerator Laboratory, POSTECH, Pohang, 305-764 (Korea, Republic of); Jung, Min-Sang; Choi, Duck-Kyun, E-mail: duck@hanyang.ac.kr, E-mail: mcjung@oist.jp [Department of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jung, Min-Cherl, E-mail: duck@hanyang.ac.kr, E-mail: mcjung@oist.jp [Energy Materials and Surface Sciences Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, 904-0495 (Japan)

    2015-08-15

    Using scanning electron microscopy (SEM) and high-resolution x-ray photoelectron spectroscopy with the synchrotron radiation we investigated Si-based micro-clusters embedded in TaSiN thin films having oxygen contamination. TaSiN thin films were deposited by co-sputtering on fixed or rotated substrates and with various power conditions of TaN and Si targets. Three types of embedded micro-clusters with the chemical states of pure Si, SiO{sub x}-capped Si, and SiO{sub 2}-capped Si were observed and analyzed using SEM and Si 2p and Ta 4f core-level spectra were derived. Their different resistivities are presumably due to the different chemical states and densities of Si-based micro-clusters.

  15. Observations on Si-based micro-clusters embedded in TaN thin film deposited by co-sputtering with oxygen contamination

    Directory of Open Access Journals (Sweden)

    Young Mi Lee

    2015-08-01

    Full Text Available Using scanning electron microscopy (SEM and high-resolution x-ray photoelectron spectroscopy with the synchrotron radiation we investigated Si-based micro-clusters embedded in TaSiN thin films having oxygen contamination. TaSiN thin films were deposited by co-sputtering on fixed or rotated substrates and with various power conditions of TaN and Si targets. Three types of embedded micro-clusters with the chemical states of pure Si, SiOx-capped Si, and SiO2-capped Si were observed and analyzed using SEM and Si 2p and Ta 4f core-level spectra were derived. Their different resistivities are presumably due to the different chemical states and densities of Si-based micro-clusters.

  16. Beam broadening of polar molecules and clusters in deflection experiments.

    Science.gov (United States)

    Bulthuis, J; Kresin, V V

    2012-01-07

    A beam of rotating dipolar particles (molecules or clusters) will broaden when passed through an electric or magnetic field gradient region. This broadening, which is a common experimental observable, can be expressed in terms of the variance of the distribution of the resulting polarization orientation (the direction cosine). Here, the broadening for symmetric-top and linear rotors is discussed. These two types of rotors have qualitatively different low-field orientation distribution functions, but behave similarly in a strong field. While analytical expressions for the polarization variance can be derived from first-order perturbation theory, for experimental guidance it is important to identify the applicability and limitations of these expressions, and the general dependence of the broadening on the experimental parameters. For this purpose, the analytical results are compared with the full diagonalization of the rotational Stark-effect matrices. Conveniently for experimental estimations, it is found that for symmetric tops, the dependence of the broadening parameter on the rotational constant, the axial ratio, and the field strength remains similar to the analytical expression even outside of the perturbative regime. Also, it is observed that the shape envelope, the centroid, and the width of the orientation distribution function for a symmetric top are quite insensitive to the value of its rotational constant (except at low rotational temperatures).

  17. A quadrupole ion trap as low-energy cluster ion beam source

    CERN Document Server

    Uchida, N; Kanayama, T

    2003-01-01

    Kinetic energy distribution of ion beams was measured by a retarding field energy analyzer for a mass-selective cluster ion beam deposition system that uses a quadrupole ion trap as a cluster ion beam source. The results indicated that the system delivers a cluster-ion beam with energy distribution of approx 2 eV, which corresponded well to the calculation results of the trapping potentials in the ion trap. Using this deposition system, mass-selected hydrogenated Si cluster ions Si sub n H sub x sup + were actually deposited on Si(111)-(7x7) surfaces at impact kinetic energy E sub d of 3-30 eV. Observation by using a scanning tunneling microscope (STM) demonstrated that Si sub 6 H sub x sup + cluster ions landed on the surface without decomposition at E sub d =3 eV, while the deposition was destructive at E sub d>=18 eV. (author)

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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)

  3. A photoionization study of hydrogen-bound clusters in a supersonic molecular beam

    International Nuclear Information System (INIS)

    Cook, K.D.; Jones, G.G.; Taylor, J.W.

    1980-01-01

    Hydrogen bonding of methanol, methanol-d, ethanol, and trifluoroethanol is investigated with a supersonic molecular beam as a sampling system for a photoionization quadrupole mass spectrometer. Monochromatized vacuum ultraviolet synchrotron radiation is used as the ionizing source. Cluster ions belonging to the series (ROH)sub(n)H + are detected when sampling up to 100-torr alcohol vapor with the molecular beam. No parent cluster molecular ions are detected. Experiments are described which exclude ion-molecule reactions in the mass spectrometer ion source as a possible origin of the cluster ions. Experimental evidence shows that nozzle temperature primarily influences the equilibrium distribution of clusters present in the nozzle source. From the dependences of relative cluster ion intensities on nozzle source temperature, the heats of formation of oligomers of the alcohols are estimated. Cooperative hydrogen bonding is not detected, expect for trifluoroethanol, where the trimer is found to be the most stable cluster. (orig.)

  4. Influence of residual Ar+ in Ar cluster ion beam for DLC film formation

    International Nuclear Information System (INIS)

    Kitagawa, Teruyuki; Miyauchi, Kazuya; Toyoda, Noriaki; Kanda, Kazuhiro; Ikeda, Tokumi; Tsubakino, Harushige; Matsuo, Jiro; Matsui, Shinji; Yamada, Isao

    2003-01-01

    In order to study the influences of residual Ar monomer ion (Ar + ) on sp 2 content and hardness of diamond like carbon (DLC) films formed by Ar cluster ion beam assisted deposition, Ar cluster ion, Ar + and their mixed ions (Ar cluster ion and Ar + ) bombardments were performed during evaporation of C 60 . From near edge X-ray absorption fine structure (NEXAFS) and Raman spectroscopy measurements, lower sp 2 content in the carbon films was obtained with Ar cluster ion bombardment than that with Ar + and mixed ion. Furthermore higher hardness and smooth surface were shown with Ar cluster ion bombardments. Therefore it was important to reduce Ar + in Ar cluster ion beams to obtain hard DLC films with flat surface

  5. Magnetism of iron, cobalt and nickel clusters studied in molecular beams

    International Nuclear Information System (INIS)

    Billas, I.

    1995-01-01

    The magnetic properties of iron, cobalt and nickel clusters in a molecular beam have been studied in a magnetic Stern-Gerlach deflection experiment. The molecular beam apparatus consists of a laser vaporization cluster source with high intensity and stability and a high-resolution time-of-flight mass spectrometer for the deflection measurements. Several novel experimental features have been developed in this work, like a nozzle which can be heated up to 1000 K and a chopper to measure the dwell times of the clusters in the source and their corresponding velocities. These new developments have allowed the measurement and the control of the temperature of the free clusters. The Stern-Gerlach deflection experiments have been performed on Fe, Co and Ni clusters in the mass range from 20 to 700 atoms. All clusters show single-sided deflection toward increasing field. This observation indicates that a spin relaxation process occurs within the isolated clusters. The participation of both the cluster rotational and vibrational degrees of freedom to the spin relaxation has been experimentally demonstrated. The cluster magnetization has been determined as a function of applied magnetic field B and as a function of dwell times of the clusters in the source before the supersonic expansion into vacuum. Superparamagnetic behavior has been observed when the cluster rotational speed is much larger than the Larmor frequency of the cluster magnetic moment μ in the field B. In particular, for μB<< kT, the cluster magnetization depends on B/T. For lower rotational speeds, reduced values of the magnetization have been observed. The magnetic moments of the superparamagnetic Fe, Co and Ni clusters have been measured as a) a function of cluster size N at low temperature and b) as a function of cluster temperature T for various size ranges. (author) figs., tabs., refs

  6. Supersonic cluster beams: a powerful method for the deposition of nanostructured thin films with tailored properties

    International Nuclear Information System (INIS)

    Milani, P.

    2002-01-01

    By using a pulsed micro-plasma cluster source and by exploiting aero-dynamical effects typical of supersonic beams it is possible to obtain very high deposition rates with a control on neutral cluster mass distribution, allowing the deposition of thin films with controlled nanostructure. Due to high deposition rates, high lateral resolution, low temperature processing supersonic cluster beams can also be used for the micro and nano-patterning of cluster-assembled films when little or no post-growth manipulation or assembly is required. For example the nano and meso-structure of films obtained by carbon cluster beam deposition can be controlled by selecting in the beam the elemental building blocks, moreover functional properties such as field emission can be controlled and tailored. The use of supersonic cluster beams opens also new perspectives for the production of nano-structured films with novel physico-chemical and topological properties such as nano-structured carbon matrices containing carbide and transition metal particles. (Author)

  7. 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

  8. 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.)

  9. A transmission electron microscopy and X-ray photoelectron spectroscopy study of annealing induced γ-phase nucleation, clustering, and interfacial dynamics in reactively sputtered amorphous alumina thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A. K. Nanda, E-mail: aknk27@yahoo.com; Subramanian, B. [ECMS Division, Central Electro Chemical Research Institute, Karaikudi (India); Prasanna, S. [Department of Physics, PSG College of Technology, Coimbatore (India); Jayakumar, S. [Department of Physics, PSG Institute of Technology and Applied Research, Coimbatore (India); Rao, G. Mohan [Department of Instrumentation, Indian Institute of Science, Bangalore (India)

    2015-03-28

    Pure α-Al{sub 2}O{sub 3} exhibits a very high degree of thermodynamical stability among all metal oxides and forms an inert oxide scale in a range of structural alloys at high temperatures. We report that amorphous Al{sub 2}O{sub 3} thin films sputter deposited over crystalline Si instead show a surprisingly active interface. On annealing, crystallization begins with nuclei of a phase closely resembling γ-Alumina forming almost randomly in an amorphous matrix, and with increasing frequency near the substrate/film interface. This nucleation is marked by the signature appearance of sharp (400) and (440) reflections and the formation of a diffuse diffraction halo with an outer maximal radius of ≈0.23 nm enveloping the direct beam. The microstructure then evolves by a cluster-coalescence growth mechanism suggestive of swift nucleation and sluggish diffusional kinetics, while locally the Al ions redistribute slowly from chemisorbed and tetrahedral sites to higher anion coordinated sites. Chemical state plots constructed from XPS data and simple calculations of the diffraction patterns from hypothetically distorted lattices suggest that the true origins of the diffuse diffraction halo are probably related to a complex change in the electronic structure spurred by the a-γ transformation rather than pure structural disorder. Concurrent to crystallization within the film, a substantially thick interfacial reaction zone also builds up at the film/substrate interface with the excess Al acting as a cationic source.

  10. A transmission electron microscopy and X-ray photoelectron spectroscopy study of annealing induced γ-phase nucleation, clustering, and interfacial dynamics in reactively sputtered amorphous alumina thin films

    Science.gov (United States)

    Kumar, A. K. Nanda; Prasanna, S.; Subramanian, B.; Jayakumar, S.; Rao, G. Mohan

    2015-03-01

    Pure α-Al2O3 exhibits a very high degree of thermodynamical stability among all metal oxides and forms an inert oxide scale in a range of structural alloys at high temperatures. We report that amorphous Al2O3 thin films sputter deposited over crystalline Si instead show a surprisingly active interface. On annealing, crystallization begins with nuclei of a phase closely resembling γ-Alumina forming almost randomly in an amorphous matrix, and with increasing frequency near the substrate/film interface. This nucleation is marked by the signature appearance of sharp (400) and (440) reflections and the formation of a diffuse diffraction halo with an outer maximal radius of ≈0.23 nm enveloping the direct beam. The microstructure then evolves by a cluster-coalescence growth mechanism suggestive of swift nucleation and sluggish diffusional kinetics, while locally the Al ions redistribute slowly from chemisorbed and tetrahedral sites to higher anion coordinated sites. Chemical state plots constructed from XPS data and simple calculations of the diffraction patterns from hypothetically distorted lattices suggest that the true origins of the diffuse diffraction halo are probably related to a complex change in the electronic structure spurred by the a-γ transformation rather than pure structural disorder. Concurrent to crystallization within the film, a substantially thick interfacial reaction zone also builds up at the film/substrate interface with the excess Al acting as a cationic source.

  11. A transmission electron microscopy and X-ray photoelectron spectroscopy study of annealing induced γ-phase nucleation, clustering, and interfacial dynamics in reactively sputtered amorphous alumina thin films

    International Nuclear Information System (INIS)

    Kumar, A. K. Nanda; Subramanian, B.; Prasanna, S.; Jayakumar, S.; Rao, G. Mohan

    2015-01-01

    Pure α-Al 2 O 3 exhibits a very high degree of thermodynamical stability among all metal oxides and forms an inert oxide scale in a range of structural alloys at high temperatures. We report that amorphous Al 2 O 3 thin films sputter deposited over crystalline Si instead show a surprisingly active interface. On annealing, crystallization begins with nuclei of a phase closely resembling γ-Alumina forming almost randomly in an amorphous matrix, and with increasing frequency near the substrate/film interface. This nucleation is marked by the signature appearance of sharp (400) and (440) reflections and the formation of a diffuse diffraction halo with an outer maximal radius of ≈0.23 nm enveloping the direct beam. The microstructure then evolves by a cluster-coalescence growth mechanism suggestive of swift nucleation and sluggish diffusional kinetics, while locally the Al ions redistribute slowly from chemisorbed and tetrahedral sites to higher anion coordinated sites. Chemical state plots constructed from XPS data and simple calculations of the diffraction patterns from hypothetically distorted lattices suggest that the true origins of the diffuse diffraction halo are probably related to a complex change in the electronic structure spurred by the a-γ transformation rather than pure structural disorder. Concurrent to crystallization within the film, a substantially thick interfacial reaction zone also builds up at the film/substrate interface with the excess Al acting as a cationic source

  12. Transformation dynamics of Ni clusters into NiO rings under electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Knez, Daniel, E-mail: daniel.knez@felmi-zfe.at [Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz (Austria); Thaler, Philipp; Volk, Alexander [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010 Graz (Austria); Kothleitner, Gerald [Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz (Austria); Ernst, Wolfgang E. [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010 Graz (Austria); Hofer, Ferdinand [Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz (Austria)

    2017-05-15

    We report the transformation of nickel clusters into NiO rings by an electron beam induced nanoscale Kirkendall effect. High-purity nickel clusters consisting of a few thousand atoms have been used as precursors and were synthesized with the superfluid helium droplet technique. Aberration-corrected, analytical scanning transmission electron microscopy was applied to oxidise and simultaneously analyse the nanostructures. The transient dynamics of the oxidation could be documented by time lapse series using high-angle annular dark-field imaging and electron energy-loss spectroscopy. A two-step Cabrera-Mott oxidation mechanism was identified. It was found that water adsorbed adjacent to the clusters acts as oxygen source for the electron beam induced oxidation. The size-dependent oxidation rate was estimated by quantitative EELS measurements combined with molecular dynamics simulations. Our findings could serve to better control sample changes during examination in an electron microscope, and might provide a methodology to generate other metal oxide nanostructures. - Highlights: • Beam induced conversion of Ni clusters into crystalline NiO rings has been observed. • Ni clusters were grown with the superfluid He-droplet technique. • oxidizeSTEM was utilized to investigate and simultaneously oxidize these clusters. • Oxidation dynamics was captured in real-time. • Cluster sizes and the oxidation rate were estimated via EELS and molecular dynamics.

  13. 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.

  14. 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

  15. Self-Assembled Gold Nano-Ripple Formation by Gas Cluster Ion Beam Bombardment.

    Science.gov (United States)

    Tilakaratne, Buddhi P; Chen, Quark Y; Chu, Wei-Kan

    2017-09-08

    In this study, we used a 30 keV argon cluster ion beam bombardment to investigate the dynamic processes during nano-ripple formation on gold surfaces. Atomic force microscope analysis shows that the gold surface has maximum roughness at an incident angle of 60° from the surface normal; moreover, at this angle, and for an applied fluence of 3 × 10 16 clusters/cm², the aspect ratio of the nano-ripple pattern is in the range of ~50%. Rutherford backscattering spectrometry analysis reveals a formation of a surface gradient due to prolonged gas cluster ion bombardment, although the surface roughness remains consistent throughout the bombarded surface area. As a result, significant mass redistribution is triggered by gas cluster ion beam bombardment at room temperature. Where mass redistribution is responsible for nano-ripple formation, the surface erosion process refines the formed nano-ripple structures.

  16. 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

  17. Reprint of: Negative carbon cluster ion beams: New evidence for the special nature of C60

    Science.gov (United States)

    Liu, Y.; O'brien, S. C.; Zhang, Q.; Heath, J. R.; Tittel, F. K.; Curl, R. F.; Kroto, H. W.; Smalley, R. E.

    2013-12-01

    Cold carbon cluster negative ions are formed by supersonic expansion of a plasma created at the nozzle of a supersonic cluster beam source by an excimer laser pulse. The observed distribution of mass peaks for the Cn- ions for n > 40 demonstrates that the evidence previously given for the special stability of neutral C60 and the existence of spheroidal carbon shells cannot be an artifact of the ionization conditions.

  18. Cluster generator

    Science.gov (United States)

    Donchev, Todor I [Urbana, IL; Petrov, Ivan G [Champaign, IL

    2011-05-31

    Described herein is an apparatus and a method for producing atom clusters based on a gas discharge within a hollow cathode. The hollow cathode includes one or more walls. The one or more walls define a sputtering chamber within the hollow cathode and include a material to be sputtered. A hollow anode is positioned at an end of the sputtering chamber, and atom clusters are formed when a gas discharge is generated between the hollow anode and the hollow cathode.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. Dielectric properties of isolated clusters beam deflection studies

    CERN Document Server

    Heiles, Sven

    2013-01-01

    A broad range of state-of-the-art methods to determine properties of clusters are presented. The experimental setup and underlying physical concepts of these experiments are described. Furthermore, existing theoretical models to explain the experimental observations are introduced and the possibility to deduce structural information from measurements of dielectric properties is discussed. Additional case studies are presented in the book to emphasize the possibilities but also drawbacks of the methods.

  5. D-Cluster Converter Foil for Laser-Accelerated Deuteron Beams: Towards Deuteron-Beam-Driven Fast Ignition

    International Nuclear Information System (INIS)

    Miley, George H.

    2012-01-01

    Fast Ignition (FI) uses Petawatt laser generated particle beam pulse to ignite a small volume called a pre-compressed Inertial Confinement Fusion (ICF) target, and is the favored method to achieve the high energy gain per target burn needed for an attractive ICF power plant. Ion beams such as protons, deuterons or heavier carbon ions are especially appealing for FI as they have relative straight trajectory, and easier to focus on the fuel capsule. But current experiments have encountered problems with the 'converter-foil' which is irradiated by the Petawatt laser to produce the ion beams. The problems include depletion of the available ions in the convertor foils, and poor energy efficiency (ion beam energy/ input laser energy). We proposed to develop a volumetrically-loaded ultra-high-density deuteron deuterium cluster material as the basis for converter-foil for deuteron beam generation. The deuterons will fuse with the ICF DT while they slow down, providing an extra 'bonus' energy gain in addition to heating the hot spot. Also, due to the volumetric loading, the foil will provide sufficient energetic deuteron beam flux for 'hot spot' ignition, while avoiding the depletion problem encountered by current proton-driven FI foils. After extensive comparative studies, in Phase I, high purity PdO/Pd/PdO foils were selected for the high packing fraction D-Cluster converter foils. An optimized loading process has been developed to increase the cluster packing fraction in this type of foil. As a result, the packing fraction has been increased from 0.1% to 10% - meeting the original Phase I goal and representing a significant progress towards the beam intensities needed for both FI and pulsed neutron applications. Fast Ignition provides a promising approach to achieve high energy gain target performance needed for commercial Inertial Confinement Fusion (ICF). This is now a realistic goal for near term in view of the anticipated ICF target burn at the National Ignition

  6. 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.

  7. 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.

  8. Electron irradiation effects in amorphous antimony thin films obtained by cluster-beam deposition

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, G.; Treilleux, M.; Santos Aires, F.; Cabaud, B.; Melinon, P.; Hoareau, A. (Lyon-1 Univ., 69 - Villeurbanne (France))

    1991-03-01

    In order to understand the differences existing between films obtained with a classical molecular beam deposition (MBD) and the new low-energy cluster beam deposition (LECBD), transmission electron microscopy has been used to characterize the first stages of antimony LECBD. Antimony deposits are discontinuous and amorphous up to 2 nm in thickness. They are formed with isolated amorphous antimony particles surrounded by an amorphous antimony oxide shell. Moreover, under electron beam exposure in the microscope, an amorphous-crystal transformation has been observed in the oxide shell. Electron irradiation induces the formation of a crystallized antimony oxide (Sb{sub 2}O{sub 3}) around the amorphous antimony core. (author).

  9. 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...

  10. 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.

  11. Intensities and cross-sections of Ar clusters in a molecular beam, ch. 3

    International Nuclear Information System (INIS)

    Deursen, A.P.J. van; Lumig, A. van; Reuss, J.

    1976-01-01

    Ar-cluster beams were produced by supersonic expansion under various source conditions. The experimental intensities have been scaled such that universal curves are obtained, up to moderate source pressures. The ratio of dimer/monomer cross-sections has been determined. (Auth.)

  12. Polar cap ion beams during periods of northward IMF: Cluster statistical results

    Directory of Open Access Journals (Sweden)

    R. Maggiolo

    2011-05-01

    Full Text Available Above the polar caps and during prolonged periods of northward IMF, the Cluster satellites detect upward accelerated ion beams with energies up to a few keV. They are associated with converging electric field structures indicating that the acceleration is caused by a quasi-static field-aligned electric field that can extend to altitudes higher than 7 RE (Maggiolo et al., 2006; Teste et al., 2007. Using the AMDA science analysis service provided by the Centre de Données de la Physique des Plasmas, we have been able to extract about 200 events of accelerated upgoing ion beams above the polar caps from the Cluster database. Most of these observations are taken at altitudes lower than 7 RE and in the Northern Hemisphere. We investigate the statistical properties of these ion beams. We analyze their geometry, the properties of the plasma populations and of the electric field inside and around the beams, as well as their dependence on solar wind and IMF conditions. We show that ~40 % of the ion beams are collocated with a relatively hot and isotropic plasma population. The density and temperature of the isotropic population are highly variable but suggest that this plasma originates from the plasma sheet. The ion beam properties do not change significantly when the isotropic, hot background population is present. Furthermore, during one single polar cap crossing by Cluster it is possible to detect upgoing ion beams both with and without an accompanying isotropic component. The analysis of the variation of the IMF BZ component prior to the detection of the beams indicates that the delay between a northward/southward turning of IMF and the appearance/disappearance of the beams is respectively ~2 h and 20 min. The observed electrodynamic characteristics of high altitude polar cap ion beams suggest that they are closely connected to polar cap auroral arcs. We discuss the implications of these Cluster observations above the polar cap on the magnetospheric

  13. Kinetic methods for measuring the temperature of clusters and nanoparticles in molecular beams

    International Nuclear Information System (INIS)

    Makarov, Grigorii N

    2011-01-01

    The temperature (internal energy) of clusters and nanoparticles is an important physical parameter which affects many of their properties and the character of processes they are involved in. At the same time, determining the temperature of free clusters and nanoparticles in molecular beams is a rather complicated problem because the temperature of small particles depends on their size. In this paper, recently developed kinetic methods for measuring the temperature of clusters and nanoparticles in molecular beams are reviewed. The definition of temperature in the present context is given, and how the temperature affects the properties of and the processes involving the particles is discussed. The temperature behavior of clusters and nanoparticles near a phase transition point is analyzed. Early methods for measuring the temperature of large clusters are briefly described. It is shown that, compared to other methods, new kinetic methods are more universal and applicable for determining the temperature of clusters and nanoparticles of practically any size and composition. The future development and applications of these methods are outlined. (reviews of topical problems)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-12-21

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

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

    International Nuclear Information System (INIS)

    Podestà, Alessandro; Borghi, Francesca; Indrieri, Marco; Bovio, Simone; Piazzoni, Claudio; Milani, Paolo

    2015-01-01

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

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

    Science.gov (United States)

    Podestà, Alessandro; Borghi, Francesca; Indrieri, Marco; Bovio, Simone; Piazzoni, Claudio; Milani, Paolo

    2015-12-01

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

  17. Summary of Industry-Academia Collaboration Projects on Cluster Ion Beam Process Technology

    International Nuclear Information System (INIS)

    Yamada, Isao; Toyoda, Noriaki; Matsuo, Jiro

    2008-01-01

    Processes employing clusters of ions comprised of a few hundred to many thousand atoms are now being developed into a new field of ion beam technology. Cluster-surface collisions produce important non-linear effects which are being applied to shallow junction formation, to etching and smoothing of semiconductors, metals, and dielectrics, to assisted formation of thin films with nano-scale accuracy, and to other surface modification applications. In 2000, a four year R and D project for development of industrial technology began in Japan under funding from the New Energy and Industrial Technology Development Organization (NEDO). Subjects of the projects are in areas of equipment development, semiconductor surface processing, high accuracy surface processing and high-quality film formation. In 2002, another major cluster ion beam project which emphasized nano-technology applications has started under a contract from the Ministry of Economy and Technology for Industry (METI). This METI project involved development related to size-selected cluster ion beam equipment and processes, and development of GCIB processes for very high rate etching and for zero damage etching of magnetic materials and compound semiconductor materials. This paper describes summery of the results.

  18. Gas cluster ion beam assisted NiPt germano-silicide formation on SiGe

    Energy Technology Data Exchange (ETDEWEB)

    Ozcan, Ahmet S., E-mail: asozcan@us.ibm.com [IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120 (United States); Lavoie, Christian; Jordan-Sweet, Jean [IBM T. J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598 (United States); Alptekin, Emre; Zhu, Frank [IBM Semiconductor Research and Development Center, 2070 Route 52, Hopewell Junction, New York 12533 (United States); Leith, Allen; Pfeifer, Brian D.; LaRose, J. D.; Russell, N. M. [TEL Epion Inc., 900 Middlesex Turnpike, Bldg. 6, Billerica, Massachusetts 01821 (United States)

    2016-04-21

    We report the formation of very uniform and smooth Ni(Pt)Si on epitaxially grown SiGe using Si gas cluster ion beam treatment after metal-rich silicide formation. The gas cluster ion implantation process was optimized to infuse Si into the metal-rich silicide layer and lowered the NiSi nucleation temperature significantly according to in situ X-ray diffraction measurements. This novel method which leads to more uniform films can also be used to control silicide depth in ultra-shallow junctions, especially for high Ge containing devices, where silicidation is problematic as it leads to much rougher interfaces.

  19. 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.)

  20. 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

  1. 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.)

  2. Formation of atomic clusters through the laser ablation of refractory materials in a supersonic molecular beam source

    International Nuclear Information System (INIS)

    Haufler, R.E.; Puretzky, A.A.; Compton, R.N.

    1993-01-01

    Concepts which guide the design of atomic cluster supersonic beam sources have been developed. These ideas are founded on the knowledge of laser ablation dynamics and are structured in order to take advantage of certain features of the ablation event. Some of the drawbacks of previous cluster source designs become apparent when the sequence of events following laser ablation are clarified. Key features of the new cluster source design include control of the cluster size distribution, uniform performance with a variety of solid materials and elements, high beam intensity, and significant removal of internal energy during the supersonic expansion

  3. Observations on small anionic clusters in an electrostatic ion beam trap

    International Nuclear Information System (INIS)

    Eritt, Markus

    2008-01-01

    The term atomic cluster relates to compounds of at least two or three atoms. Thereby the physical properties are size dependent and the property transitions between single atoms and bulk material are not always smooth. Ion traps allow it to observe internal cluster properties independent from the influence of external forces. In this work the electron induced decay of singly negatively charged atomic clusters was observed. The dissociation cross section of the clusters is dominated by detachment of the only weakly bound outer electrons. For simple atoms at low electron energies a simple scaling law can be obtained that includes only the binding energies of the valence electrons. Nevertheless for larger sizes theoretical calculations predict so called ''giant resonances'' as dominant decay process in metal clusters. Due to mass limitations in storage rings exist so far only cross section measurements for simple anions and small negative molecules. In this work the electron detachment cross sections of small negatively charged carbon (C n - n=2-12), aluminium (Al n - n=2-7) and silver clusters (Ag n - n=1-11) were measured in an electrostatic ion beam trap. The classical scaling law, including only the binding energies of the valence electrons, turned out to be not sufficient, especially for larger clusters. In order to improve the correlation between measured and predicted values it was proposed to involve the influence of the cluster volume and the specific polarisability induced by long range coulomb interaction. For silver clusters the best agreement was obtained using a combination of the projected area reduced by the polarisability. The existence of ''giant resonances'' could not be confirmed. According to theory for clusters with a broad internal energy distribution, a power-law decay close to 1/time is expected. For some clusters the lifetime behaviour would be strongly quenched by photon emission. The thermionic evaporative decay of anionic aluminium and

  4. Observations on small anionic clusters in an electrostatic ion beam trap

    Energy Technology Data Exchange (ETDEWEB)

    Eritt, Markus

    2008-10-02

    The term atomic cluster relates to compounds of at least two or three atoms. Thereby the physical properties are size dependent and the property transitions between single atoms and bulk material are not always smooth. Ion traps allow it to observe internal cluster properties independent from the influence of external forces. In this work the electron induced decay of singly negatively charged atomic clusters was observed. The dissociation cross section of the clusters is dominated by detachment of the only weakly bound outer electrons. For simple atoms at low electron energies a simple scaling law can be obtained that includes only the binding energies of the valence electrons. Nevertheless for larger sizes theoretical calculations predict so called ''giant resonances'' as dominant decay process in metal clusters. Due to mass limitations in storage rings exist so far only cross section measurements for simple anions and small negative molecules. In this work the electron detachment cross sections of small negatively charged carbon (C{sub n}{sup -} n=2-12), aluminium (Al{sub n}{sup -} n=2-7) and silver clusters (Ag{sub n}{sup -} n=1-11) were measured in an electrostatic ion beam trap. The classical scaling law, including only the binding energies of the valence electrons, turned out to be not sufficient, especially for larger clusters. In order to improve the correlation between measured and predicted values it was proposed to involve the influence of the cluster volume and the specific polarisability induced by long range coulomb interaction. For silver clusters the best agreement was obtained using a combination of the projected area reduced by the polarisability. The existence of ''giant resonances'' could not be confirmed. According to theory for clusters with a broad internal energy distribution, a power-law decay close to 1/time is expected. For some clusters the lifetime behaviour would be strongly quenched by photon

  5. Advanced carbon-based material C60 modification using partially ionized cluster and energetic beams

    International Nuclear Information System (INIS)

    Du Yuancheng; Ren Zhongmin; Ning Zhifeng; Xu Ning; Li Fuming

    1997-01-01

    Two processes have been undertaken using Partially ionized cluster deposition (PICBD) and energetic ion bombardment beams deposition (IBD) respectively. C 60 films deposited by PICBD at V=0 and 65 V, which result in highly textured close-packed structure in orientation (110) and being more polycrystalline respectively, the resistance of C 60 films to oxygen diffusion contamination will be improved. In the case of PICBD, the ionized C 60 soccer-balls molecules in the evaporation beams will be fragmented in collision with the substrate under the elevated accelerating fields Va. As a new synthetic IBD processing, two low energy (400 and 1000 eV) nitrogen ion beams have been used to bombard C 60 films to synthesize the carbon nitride films

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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)

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. The Atacama Cosmology Telescope (ACT): Beam Profiles and First SZ Cluster Maps

    Science.gov (United States)

    Hincks, A. D.; Acquaviva, V.; Ade, P. A.; Aguirre, P.; Amiri, M.; Appel, J. W.; Barrientos, L. F.; Battistelli, E. S.; Bond, J. R.; Brown, B.; hide

    2010-01-01

    The Atacama Cosmology Telescope (ACT) is currently observing the cosmic microwave background with arcminute resolution at 148 GHz, 218 GHz, and 277 GHz, In this paper, we present ACT's first results. Data have been analyzed using a maximum-likelihood map-making method which uses B-splines to model and remove the atmospheric signal. It has been used to make high-precision beam maps from which we determine the experiment's window functions, This beam information directly impacts all subsequent analyses of the data. We also used the method to map a sample of galaxy clusters via the Sunyaev-Ze1'dovich (SZ) effect, and show five clusters previously detected with X-ray or SZ observations, We provide integrated Compton-y measurements for each cluster. Of particular interest is our detection of the z = 0.44 component of A3128 and our current non-detection of the low-redshift part, providing strong evidence that the further cluster is more massive as suggested by X-ray measurements. This is a compelling example of the redshift-independent mass selection of the SZ effect.

  17. Formation of aluminum films on silicon by ion beam deposition: a comparison with ionized cluster beam deposition

    International Nuclear Information System (INIS)

    Zuhr, R.A.; Haynes, T.E.; Galloway, M.D.; Tanaka, S.; Yamada, A.; Yamada, I.

    1991-01-01

    The direct ion beam deposition (IBD) technique has been used to study the formation of oriented aluminum films on single crystal silicon substrates. In the IBD process, thin film growth is accomplished by decelerating a magnetically analyzed ion beam to low energies (10-200 eV) for direct deposition onto the substrate under UHV conditions. The aluminum-on-silicon system is one which has been studied extensively by ionized cluster beam (ICB) deposition. This technique has produced intriguing results for aluminum, with oriented crystalline films being formed at room temperature in spite of the 25% mismatch in lattice constant between aluminum and silicon. In this work, we have studied the formation of such films by IBD, with emphasis on the effects of ion energy, substrate temperature, and surface cleanliness. Oriented films have been grown on Si(111) at temperatures from 40 to 300degC and with ion energies of 30-120 eV per ion. Completed films were analyzed by ion scattering, X-ray diffraction, scanning-electron microscopy, and optical microscopy. Results achieved for thin films grown by IBD are comparable to those for similar films grown by ICB deposition. (orig.)

  18. 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

  19. 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

  20. 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.

  1. An easy-to-use method for measuring the flux of free atoms in a cluster beam

    International Nuclear Information System (INIS)

    Cuvellier, J.; Binet, A.

    1988-01-01

    A method is proposed to measure the flux of free atoms remaining in a beam of clusters. The time-of-flight (TOF) of an Ar beam containing clusters was analysed for this purpose using an electron impact + quadrupole mass spectrometer as detector. When considering TOF's with mass settings at Ar + , a double mode structure was observed. The slow component was interpreted as coming from Ar clusters that fragment as Ar + in the ionization chamber of the detector. The rapid mode in the TOF's was linked to the free atoms remaining in the Ar beam. Evaluating the area of this mode allowed one to measure the flux of free atoms in the Ar beam. The method is not restricted to measurements on Ar beams

  2. 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.

  3. 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.

  4. 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

  5. C60 ion sputtering of layered organic materials

    International Nuclear Information System (INIS)

    Shard, Alexander G.; Green, Felicia M.; Gilmore, Ian S.

    2008-01-01

    Two different organic materials, Irganox1010 and Irganox3114, were vacuum deposited as alternating layers. The layers of Irganox3114 were thin (∼2.5 nm) in comparison to the Irganox1010 (∼55 or ∼90 nm); we call these 'organic delta layers'. Both materials are shown to have identical sputtering yields and the alternating layers may be used to determine some of the important metrological parameters for cluster ion beam depth profiling of organic materials. The sputtering yield for C 60 ions is shown to diminish with ion dose. Comparison with atomic force microscopy data from films of pure Irganox1010, demonstrates that the depth resolution is limited by the development of topography. Secondary ion intensities are a well-behaved function of sputtering yield and may be employed to obtain useful analytical information. Organic delta layers are shown to be valuable reference materials for comparing the capabilities of different cluster ion sources and experimental arrangements for the depth profiling of organic materials.

  6. Cluster-transfer reactions with radioactive beams: a spectroscopic tool for neutron-rich nuclei

    CERN Document Server

    AUTHOR|(CDS)2086156; Raabe, Riccardo; Bracco, Angela

    In this thesis work, an exploratory experiment to investigate cluster-transfer reactions with radioactive beams in inverse kinematics is presented. The aim of the experiment was to test the potential of cluster-transfer reactions at the Coulomb barrier, as a possible mean to perform $\\gamma$ spectroscopy studies of exotic neutron-rich nuclei at medium-high energies and spins. The experiment was performed at ISOLDE (CERN), employing the heavy-ion reaction $^{98}$Rb + $^{7}$Li at 2.85 MeV/A. Cluster-transfer reaction channels were studied through particle-$\\gamma$ coincidence measurements, using the MINIBALL Ge array coupled to the charged particle Si detectors T-REX. Sr, Y and Zr neutron-rich nuclei with A $\\approx$ 100 were populated by either triton- or $\\alpha$ transfer from $^{7}$Li to the beam nuclei and the emitted complementary charged fragment was detected in coincidence with the $\\gamma$ cascade of the residues, after few neutrons evaporation. The measured $\\gamma$ spectra were studied in detail and t...

  7. 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.)

  8. 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.

  9. Site-specific fragmentation of polystyrene molecule using size-selected Ar gas cluster ion beam

    International Nuclear Information System (INIS)

    Moritani, Kousuke; Mukai, Gen; Hashinokuchi, Michihiro; Mochiji, Kozo

    2009-01-01

    The secondary ion mass spectrum (SIMS) of a polystyrene thin film was investigated using a size-selected Ar gas cluster ion beam (GCIB). The fragmentation in the SIM spectrum varied by kinetic energy per atom (E atom ); the E atom dependence of the secondary ion intensity of the fragment species of polystyrene can be essentially classified into three types based on the relationship between E atom and the dissociation energy of a specific bonding site in the molecule. These results indicate that adjusting E atom of size-selected GCIB may realize site-specific bond breaking within a molecule. (author)

  10. Study on interaction of swift cluster ion beam with matter and irradiation effect (Joint research)

    International Nuclear Information System (INIS)

    Saito, Yuichi; Shibata, Hiromi

    2010-07-01

    This review covers results of the 'Study of interaction on swift cluster ion beam with matter and irradiation effect' supported by the Interorganization Atomic Energy Research Program from 2006FY to 2008FY. It is composed of a research abstract for each sub-group with viewgraphs which were presented at the group meeting held on March 2009 or 'Meeting of High LET radiation -From fundamental study among physics, chemistry and biology to medical applications-' sponsored by Japan Society of Radiation Chemistry, cosponsored by this research group. (author)

  11. Sputtering and reflection of self-bombardment of tungsten material

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Guo-jian [University of Science and Technology of China, Hefei (China); Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Li, Xiao-chun; Xu, Qian; Yang, Zhong-shi [Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Luo, Guang-nan, E-mail: gnluo@ipp.ac.cn [University of Science and Technology of China, Hefei (China); Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Hefei Center for Physical Science and Technology, Hefei (China); Hefei Science Center of CAS, Hefei (China)

    2015-04-15

    In present research, the sputtering and reflection yield of self-bombardment of tungsten are investigated with the aid of molecular dynamics simulations. The source of sputtered and reflected atoms is detected by traced the original locations of sputtered and reflected atoms. Results show that for the reflected atoms no specific region exists which means cluster atoms are randomly reflected. But almost all of sputtered atoms are from a conical region under the landing point of cluster. So we can determine the sputtering yield by study the dimension of the sputtering region. Molecular dynamics shows the depth and radius of the conical are power functions of impacting energy. The effects of cluster size and temperature of target on sputtering and reflection rate are also preformed in present study. Both sputtering and reflection yield are proportion to cluster size in present cluster size, i.e. 66–2647 atoms. Higher target temperature can increase sputtering yield and deduce sputtering threshold energy, but little effect on reflection rate.

  12. Sputtering and reflection of self-bombardment of tungsten material

    International Nuclear Information System (INIS)

    Niu, Guo-jian; Li, Xiao-chun; Xu, Qian; Yang, Zhong-shi; Luo, Guang-nan

    2015-01-01

    In present research, the sputtering and reflection yield of self-bombardment of tungsten are investigated with the aid of molecular dynamics simulations. The source of sputtered and reflected atoms is detected by traced the original locations of sputtered and reflected atoms. Results show that for the reflected atoms no specific region exists which means cluster atoms are randomly reflected. But almost all of sputtered atoms are from a conical region under the landing point of cluster. So we can determine the sputtering yield by study the dimension of the sputtering region. Molecular dynamics shows the depth and radius of the conical are power functions of impacting energy. The effects of cluster size and temperature of target on sputtering and reflection rate are also preformed in present study. Both sputtering and reflection yield are proportion to cluster size in present cluster size, i.e. 66–2647 atoms. Higher target temperature can increase sputtering yield and deduce sputtering threshold energy, but little effect on reflection rate

  13. 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

  14. Probing thin over layers with variable energy/cluster ion beams

    International Nuclear Information System (INIS)

    Spool, A.; White, R.

    2006-01-01

    A series of carbon-coated magnetic recording disks proved ideal for exploring sampling depth and ion formation trends as a function of variations in energy and cluster size (Au x ) of the primary ion beam, and variations in over coat thickness and type. Ion yield from the underlying metal layer increased with increasing energy and decreasing cluster size of the primary ions. The yields varied nearly linearly with over layer thickness. In contrast, M x Cs y depth profiles were unaffected by changes in the primary ion. The samples were fortuitously dosed with dinonyl phthalate, allowing a study similar to prior GSIMS work [I.S. Gilmore, M.P. Seah, J.E. Johnstone, in: A. Benninghoven, P. Bertrand, H.-N. Migeon, H.W. Werner (Eds.), Proceedings of the 12th International Conference on SIMS, Elsevier, Brussels, 2000, p. 801]. Ions prominent in the EI mass spectrum, including even electron ions, were more consistently enhanced at lower energies and higher cluster sizes than the primary (M + H) + ion. The total secondary ion count was inversely proportional to the film thickness. Secondary electrons, largely originating in the buried metal layer, may be inducing organic ion formation [A.M. Spool, Surf. Interface Anal. 36 (2004) 264

  15. 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)

  16. 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

  17. 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)

  18. 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?

  19. 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.

  20. Measuring the Density of a Molecular Cluster Injector via Visible Emission from an Electron Beam

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, D. P.; Kaita, R.; Majeski, R. M.; Stotler, D. P.

    2010-06-28

    A method to measure the density distribution of a dense hydrogen gas jet is pre- sented. A Mach 5.5 nozzle is cooled to 80K to form a flow capable of molecular cluster formation. A 250V, 10mA electron beam collides with the jet and produces Hα emission that is viewed by a fast camera. The high density of the jet, several 1016cm-3, results in substantial electron depletion, which attenuates the Hα emission. The attenuated emission measurement, combined with a simplified electron-molecule collision model, allows us to determine the molecular density profile via a simple iterative calculation.

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

    International Nuclear Information System (INIS)

    Bettini, L.G.; Piseri, P.; De Giorgio, F.; Arbizzani, C.; Milani, P.; Soavi, F.

    2015-01-01

    Highlights: • We exploited Supersonic Cluster Beam Deposition for the fabrication of a flexible, planar micro-supercapacitor featuring nanostructured carbon electrodes deposited on a plastic Mylar substrate and N-trimethyl-N-propyl-ammonium bis(trifluoromethanesulfonyl) imide (N 1113 TFSI) ionic liquid electrolyte. • The micro-supercapacitor operates at 3 V above RT up to 80 °C with a capacitance density approaching 10 F cm −3 and delivering maximum specific energy and power densities of 10 mWh cm −3 and 8-10 W cm −3 . • The micro-supercapacitor features long cycling stability over 2x10 4 cycle on flat and bent configuration. -- Graphical abstract: Display Omitted -- Abstract: Power generation and storage in electronics require flexible, thin micro-electrochemical energy storage/conversion systems. Micro-supercapacitors (μSCs) with double-layer capacitance carbon electrodes are attracting much attention for their capability of delivering short power pulses with high stability over repeated charge/discharge cycling. Supersonic Cluster Beam Deposition (SCBD) is an effective strategy for the development of nanostructured, binder-free porous carbon electrodes on temperature sensitive substrates including polymers. We exploited SCBD for the development of a flexible, planar μSC featuring nanostructured carbon (ns-C) electrodes deposited on a plastic Mylar substrate and N-trimethyl-N-propyl-ammonium bis(trifluoromethanesulfonyl) imide (N 1113 TFSI) ionic liquid electrolyte. The electrochemical performance at different temperatures of the μSC which operates at 3 V above RT up to 80 °C with a capacitance density approaching 10 F cm −3 and delivering maximum specific energy and power densities of 10 mWh cm −3 and 8-10 W cm −3 with long cycling stability over 2 × 10 4 cycles is here reported and discussed

  2. Monoatomic and cluster beam effect on ToF-SIMS spectra of self-assembled monolayers on gold

    Energy Technology Data Exchange (ETDEWEB)

    Tuccitto, N. [Dipartimento di Scienze Chimiche Universita degli Studi di Catania, v.le A. Doria 6, 95125, Catania (Italy)], E-mail: n.tuccitto@unict.it; Torrisi, V.; Delfanti, I.; Licciardello, A. [Dipartimento di Scienze Chimiche Universita degli Studi di Catania, v.le A. Doria 6, 95125, Catania (Italy)

    2008-12-15

    Self-assembled monolayers represent well-defined systems that is a good model surface to study the effect of primary ion beams used in secondary ion mass spectrometry. The effect of polyatomic primary beams on both aliphatic and aromatic self-assembled monolayers has been studied. In particular, we analysed the variation of the relative secondary ion yield of both substrate metal-cluster (Au{sub n}{sup -}) in comparison with the molecular ions (M{sup -}) and clusters (M{sub x}Au{sub y}{sup -}) by using Bi{sup +}, Bi{sub 3}{sup +}, Bi{sub 5}{sup +} beams. Moreover, the differences in the secondary ion generation efficiency are discussed. The main effect of the cluster beams is related to an increased formation of low-mass fragments and to the enhancement of the substrate related gold-clusters. The results show that, at variance of many other cases, the static SIMS of self-assembled monolayers does not benefit of the use of polyatomic primary ions.

  3. Sputtering and mixing of supported nanoparticles

    International Nuclear Information System (INIS)

    Jiménez-Sáez, J.C.; Pérez-Martín, A.M.C.; Jiménez-Rodríguez, J.J.

    2013-01-01

    Sputtering and mixing of Co nanoparticles supported in Cu(0 0 1) under 1-keV argon bombardment are studied using molecular-dynamics simulations. Particles of different initial size have been considered. The cluster height decreases exponentially with increasing fluence. In nanoparticles, sputtering yield is significantly enhanced compared to bulk. In fact, the value of this magnitude depends on the cluster height. A theoretical model for sputtering is introduced with acceptable results compared to those obtained by simulation. Discrepancies happen mainly for very small particles. Mixing rate at the interface is quantified; and besides, the influence of border effects for clusters of different initial size is assessed. Mixing rate and border length–surface area ratio for the initial interface show a proportionality relation. The phenomenon of ion-induced burrowing of metallic nanoparticles is analysed

  4. 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.)

  5. 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

  6. 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.)

  7. 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

  8. Tribological coatings for complex mechanical elements produced by supersonic cluster beam deposition of metal dichalcogenide nanoparticles

    Science.gov (United States)

    Piazzoni, C.; Buttery, M.; Hampson, M. R.; Roberts, E. W.; Ducati, C.; Lenardi, C.; Cavaliere, F.; Piseri, P.; Milani, P.

    2015-07-01

    Fullerene-like MoS2 and WS2 nanoparticles can be used as building blocks for the fabrication of fluid and solid lubricants. Metal dichalcogenide films have a very low friction coefficient in vacuum, therefore they have mostly been used as solid lubricants in space and vacuum applications. Unfortunately, their use is significantly hampered by the fact that in the presence of humidity, oxygen and moisture, the low-friction properties of these materials rapidly degrade due to oxidation. The use of closed-cage MoS2 and WS2 nanoparticles may eliminate this problem, although the fabrication of lubricant thin films starting from dichalcogenide nanoparticles is, to date, a difficult task. Here we demonstrate the use of supersonic cluster beam deposition for the coating of complex mechanical elements (angular contact ball bearings) with nanostructured MoS2 and WS2 thin films. We report structural and tribological characterization of the coatings in view of the optimization of tribological performances for aerospace applications.

  9. The quantitative analysis of silicon carbide surface smoothing by Ar and Xe cluster ions

    Science.gov (United States)

    Ieshkin, A. E.; Kireev, D. S.; Ermakov, Yu. A.; Trifonov, A. S.; Presnov, D. E.; Garshev, A. V.; Anufriev, Yu. V.; Prokhorova, I. G.; Krupenin, V. A.; Chernysh, V. S.

    2018-04-01

    The gas cluster ion beam technique was used for the silicon carbide crystal surface smoothing. The effect of processing by two inert cluster ions, argon and xenon, was quantitatively compared. While argon is a standard element for GCIB, results for xenon clusters were not reported yet. Scanning probe microscopy and high resolution transmission electron microscopy techniques were used for the analysis of the surface roughness and surface crystal layer quality. The gas cluster ion beam processing results in surface relief smoothing down to average roughness about 1 nm for both elements. It was shown that xenon as the working gas is more effective: sputtering rate for xenon clusters is 2.5 times higher than for argon at the same beam energy. High resolution transmission electron microscopy analysis of the surface defect layer gives values of 7 ± 2 nm and 8 ± 2 nm for treatment with argon and xenon clusters.

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

    International Nuclear Information System (INIS)

    Simone, Monica de; Snidero, Elena; Coreno, Marcello; Bongiorno, Gero; Giorgetti, Luca; Amati, Matteo; Cepek, Cinzia

    2012-01-01

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

  11. 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

  12. 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

  13. 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.

  14. 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.)

  15. Gas cluster ion beam for the characterization of organic materials in submarine basalts as Mars analogs

    International Nuclear Information System (INIS)

    Sano, Naoko; Barlow, Anders J.; Cumpson, Peter J.; Purvis, Graham W. H.; Abbott, Geoffrey D.; Gray, Neil N. D.

    2016-01-01

    The solar system contains large quantities of organic compounds that can form complex molecular structures. The processing of organic compounds by biological systems leads to molecules with distinctive structural characteristics; thus, the detection and characterization of organic materials could lead to a high degree of confidence in the existence of extra-terrestrial life. Given the nature of the surface of most planetary bodies in the solar system, evidence of life is more likely to be found in the subsurface where conditions are more hospitable. Basalt is a common rock throughout the solar system and the primary rock type on Mars and Earth. Basalt is therefore a rock type that subsurface life might exploit and as such a suitable material for the study of methods required to detect and analyze organic material in rock. Telluric basalts from Earth represent an analog for extra-terrestrial rocks where the indigenous organic matter could be analyzed for molecular biosignatures. This study focuses on organic matter in the basalt with the use of surface analysis techniques utilizing Ar gas cluster ion beams (GCIB); time of flight secondary ion mass spectrometry (ToF-SIMS), and x-ray photoelectron spectroscopy (XPS), to characterize organic molecules. Tetramethylammonium hydroxide (TMAH) thermochemolysis was also used to support the data obtained using the surface analysis techniques. The authors demonstrate that organic molecules were found to be heterogeneously distributed within rock textures. A positive correlation was observed to exist between the presence of microtubule textures in the basalt and the organic compounds detected. From the results herein, the authors propose that ToF-SIMS with an Ar GCIB is effective at detecting organic materials in such geological samples, and ToF-SIMS combined with XPS and TMAH thermochemolysis may be a useful approach in the study of extra-terrestrial organic material and life.

  16. Gas cluster ion beam for the characterization of organic materials in submarine basalts as Mars analogs

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Naoko, E-mail: naoko.sano@ncl.ac.uk; Barlow, Anders J.; Cumpson, Peter J. [National EPSRC XPS Users' Service (NEXUS), School of Mechanical and Systems Engineering, Stephenson Building, Newcastle University, Newcastle-upon-Tyne NE1 7RU (United Kingdom); Purvis, Graham W. H.; Abbott, Geoffrey D.; Gray, Neil N. D. [School of Civil Engineering and Geosciences, Devonshire Building, Newcastle University, Newcastle-upon-Tyne NE1 7RU (United Kingdom)

    2016-07-15

    The solar system contains large quantities of organic compounds that can form complex molecular structures. The processing of organic compounds by biological systems leads to molecules with distinctive structural characteristics; thus, the detection and characterization of organic materials could lead to a high degree of confidence in the existence of extra-terrestrial life. Given the nature of the surface of most planetary bodies in the solar system, evidence of life is more likely to be found in the subsurface where conditions are more hospitable. Basalt is a common rock throughout the solar system and the primary rock type on Mars and Earth. Basalt is therefore a rock type that subsurface life might exploit and as such a suitable material for the study of methods required to detect and analyze organic material in rock. Telluric basalts from Earth represent an analog for extra-terrestrial rocks where the indigenous organic matter could be analyzed for molecular biosignatures. This study focuses on organic matter in the basalt with the use of surface analysis techniques utilizing Ar gas cluster ion beams (GCIB); time of flight secondary ion mass spectrometry (ToF-SIMS), and x-ray photoelectron spectroscopy (XPS), to characterize organic molecules. Tetramethylammonium hydroxide (TMAH) thermochemolysis was also used to support the data obtained using the surface analysis techniques. The authors demonstrate that organic molecules were found to be heterogeneously distributed within rock textures. A positive correlation was observed to exist between the presence of microtubule textures in the basalt and the organic compounds detected. From the results herein, the authors propose that ToF-SIMS with an Ar GCIB is effective at detecting organic materials in such geological samples, and ToF-SIMS combined with XPS and TMAH thermochemolysis may be a useful approach in the study of extra-terrestrial organic material and life.

  17. Growth of CdTe on Si(100) surface by ionized cluster beam technique: Experimental and molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Araghi, Houshang, E-mail: araghi@aut.ac.ir [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Zabihi, Zabiholah [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Nayebi, Payman [Department of Physics, College of Technical and Engineering, Saveh Branch, Islamic Azad University, Saveh (Iran, Islamic Republic of); Ehsani, Mohammad Mahdi [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2016-10-15

    II–VI semiconductor CdTe was grown on the Si(100) substrate surface by the ionized cluster beam (ICB) technique. In the ICB method, when vapors of solid materials such as CdTe were ejected through a nozzle of a heated crucible into a vacuum region, nanoclusters were created by an adiabatic expansion phenomenon. The clusters thus obtained were partially ionized by electron bombardment and then accelerated onto the silicon substrate at 473 K by high potentials. The cluster size was determined using a retarding field energy analyzer. The results of X-ray diffraction measurements indicate the cubic zinc blende (ZB) crystalline structure of the CdTe thin film on the silicon substrate. The CdTe thin film prepared by the ICB method had high crystalline quality. The microscopic processes involved in the ICB deposition technique, such as impact and coalescence processes, have been studied in detail by molecular dynamics (MD) simulation.

  18. 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.

  19. Molecular Beam Epitaxy on Gas Cluster Ion Beam Prepared GaSb Substrates: Towards Improved Surfaces and Interfaces

    National Research Council Canada - National Science Library

    Krishnaswami, Kannan; Vangala, Shivashankar R; Dauplaise, Helen M; Allen, Lisa P; Dallas, Gordon; Bakken, Daniel; Bliss, David F; Goodhue, WIlliam D

    2007-01-01

    ... at temperatures ranging 530 degrees C to 560 degrees C. Cross-sectional transmission electron microscopy of molecular beam epitaxy grown GaSb/AlGaSb layers showed that the HBr-GCIB surface produced a smooth dislocation-free substrate-to-epi transition...

  20. Nonlinear damage effect in graphene synthesis by C-cluster ion implantation

    International Nuclear Information System (INIS)

    Zhang Rui; Zhang Zaodi; Wang Zesong; Wang Shixu; Wang Wei; Fu Dejun; Liu Jiarui

    2012-01-01

    We present few-layer graphene synthesis by negative carbon cluster ion implantation with C 1 , C 2 , and C 4 at energies below 20 keV. The small C-clusters were produced by a source of negative ion by cesium sputtering with medium beam current. We show that the nonlinear effect in cluster-induced damage is favorable for graphene precipitation compared with monomer carbon ions. The nonlinear damage effect in cluster ion implantation shows positive impact on disorder reduction, film uniformity, and the surface smoothness in graphene synthesis.

  1. Intensities and cross sections of Ne, H2, N2, NO and O2 clusters in a molecular beam, ch. 4

    International Nuclear Information System (INIS)

    Deursen, A.P.J. van; Reuss, J.

    1976-01-01

    Molecular beams of Ne, H 2 , N 2 , NO, and O 2 clusters have been investigated. The temperature and pressure dependence of the ion signals have been measured for masses up to three times the monomer mass. (Auth.)

  2. Computer simulation of sputtering: A review

    International Nuclear Information System (INIS)

    Robinson, M.T.; Hou, M.

    1992-08-01

    In 1986, H. H. Andersen reviewed attempts to understand sputtering by computer simulation and identified several areas where further research was needed: potential energy functions for molecular dynamics (MD) modelling; the role of inelastic effects on sputtering, especially near the target surface; the modelling of surface binding in models based on the binary collision approximation (BCA); aspects of cluster emission in MD models; and angular distributions of sputtered particles. To these may be added kinetic energy distributions of sputtered particles and the relationships between MD and BCA models, as well as the development of intermediate models. Many of these topics are discussed. Recent advances in BCA modelling include the explicit evaluation of the time in strict BCA codes and the development of intermediate codes able to simulate certain many-particle problems realistically. Developments in MD modelling include the wide-spread use of many-body potentials in sputtering calculations, inclusion of realistic electron excitation and electron-phonon interactions, and several studies of cluster ion impacts on solid surfaces

  3. 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.

  4. 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.

  5. 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

  6. High-throughput shadow mask printing of passive electrical components on paper by supersonic cluster beam deposition

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, Francesco; Bellacicca, Andrea; Milani, Paolo, E-mail: pmilani@mi.infn.it [CIMaINa and Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy)

    2016-04-18

    We report the rapid prototyping of passive electrical components (resistors and capacitors) on plain paper by an additive and parallel technology consisting of supersonic cluster beam deposition (SCBD) coupled with shadow mask printing. Cluster-assembled films have a growth mechanism substantially different from that of atom-assembled ones providing the possibility of a fine tuning of their electrical conduction properties around the percolative conduction threshold. Exploiting the precise control on cluster beam intensity and shape typical of SCBD, we produced, in a one-step process, batches of resistors with resistance values spanning a range of two orders of magnitude. Parallel plate capacitors with paper as the dielectric medium were also produced with capacitance in the range of tens of picofarads. Compared to standard deposition technologies, SCBD allows for a very efficient use of raw materials and the rapid production of components with different shape and dimensions while controlling independently the electrical characteristics. Discrete electrical components produced by SCBD are very robust against deformation and bending, and they can be easily assembled to build circuits with desired characteristics. The availability of large batches of these components enables the rapid and cheap prototyping and integration of electrical components on paper as building blocks of more complex systems.

  7. 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.)

  8. clusters

    Indian Academy of Sciences (India)

    2017-09-27

    Sep 27, 2017 ... Author for correspondence (zh4403701@126.com). MS received 15 ... lic clusters using density functional theory (DFT)-GGA of the DMOL3 package. ... In the process of geometric optimization, con- vergence thresholds ..... and Postgraduate Research & Practice Innovation Program of. Jiangsu Province ...

  9. clusters

    Indian Academy of Sciences (India)

    environmental as well as technical problems during fuel gas utilization. ... adsorption on some alloys of Pd, namely PdAu, PdAg ... ried out on small neutral and charged Au24,26,27, Cu,28 ... study of Zanti et al.29 on Pdn (n = 1–9) clusters.

  10. 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...

  11. Cluster-assistant generation of multiply charged atomic ions in nanosecond laser ionization of seeded methyl iodide beam

    International Nuclear Information System (INIS)

    Luo Xiaolin; Niu Dongmei; Kong Xianglei; Wen Lihua; Liang Feng; Pei Kemei; Wang Bin; Li Haiyang

    2005-01-01

    The photoionization of methyl iodide beam seeded in argon and helium is studied by time-of-flight mass spectrometry using a 25 ns, 532 nm Nd-YAG laser with intensities in the range of 2 x 10 10 -2 x 10 11 W/cm 2 . Multiply charged ions of I q+ (q = 2-3) and C 2+ with tens of eV kinetic energies have been observed when laser interacts with the middle part of the pulsed molecular beam, whose peak profiles are independent on the laser polarization directions. Strong evidences show that these ions are coming from the Coulomb explosion of multiply charged CH 3 I clusters, and laser induced inverse bremsstrahlung absorption of caged electrons plays a key role in the formation of multiply charged ions

  12. 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.)

  13. Comparative Study of Antibacterial Properties of Polystyrene Films with TiOx and Cu Nanoparticles Fabricated using Cluster Beam Technique

    DEFF Research Database (Denmark)

    Popok, Vladimir; Jeppesen, Cesarino; Fojan, Peter

    2018-01-01

    Background: Antibacterial materials are of high importance for medicine, food production and conservation. Among these materials, polymer films with metals nanoparticles (NPs) are of considerable attention for many practical applications. Results: The paper describes a novel approach...... for the formation of bactericidal media which are represented by thin polymer films (polystyrene in the current case), produced by spin-coating, with Ti and Cu NPs deposited from cluster beams. Ti NPs are treated in three different ways in order to study different approaches for oxidation and, thus, efficiency...

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  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. Improved mass resolution and mass accuracy in TOF-SIMS spectra and images using argon gas cluster ion beams.

    Science.gov (United States)

    Shon, Hyun Kyong; Yoon, Sohee; Moon, Jeong Hee; Lee, Tae Geol

    2016-06-09

    The popularity of argon gas cluster ion beams (Ar-GCIB) as primary ion beams in time-of-flight secondary ion mass spectrometry (TOF-SIMS) has increased because the molecular ions of large organic- and biomolecules can be detected with less damage to the sample surfaces. However, Ar-GCIB is limited by poor mass resolution as well as poor mass accuracy. The inferior quality of the mass resolution in a TOF-SIMS spectrum obtained by using Ar-GCIB compared to the one obtained by a bismuth liquid metal cluster ion beam and others makes it difficult to identify unknown peaks because of the mass interference from the neighboring peaks. However, in this study, the authors demonstrate improved mass resolution in TOF-SIMS using Ar-GCIB through the delayed extraction of secondary ions, a method typically used in TOF mass spectrometry to increase mass resolution. As for poor mass accuracy, although mass calibration using internal peaks with low mass such as hydrogen and carbon is a common approach in TOF-SIMS, it is unsuited to the present study because of the disappearance of the low-mass peaks in the delayed extraction mode. To resolve this issue, external mass calibration, another regularly used method in TOF-MS, was adapted to enhance mass accuracy in the spectrum and image generated by TOF-SIMS using Ar-GCIB in the delayed extraction mode. By producing spectra analyses of a peptide mixture and bovine serum albumin protein digested with trypsin, along with image analyses of rat brain samples, the authors demonstrate for the first time the enhancement of mass resolution and mass accuracy for the purpose of analyzing large biomolecules in TOF-SIMS using Ar-GCIB through the use of delayed extraction and external mass calibration.

  5. 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

  6. 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

  7. Role of isolated and clustered DNA damage and the post-irradiating repair process in the effects of heavy ion beam irradiation

    International Nuclear Information System (INIS)

    Tokuyama, Yuka; Terato, Hiroaki; Furusawa, Yoshiya; Ide, Hiroshi; Yasui, Akira

    2015-01-01

    Clustered DNA damage is a specific type of DNA damage induced by ionizing radiation. Any type of ionizing radiation traverses the target DNA molecule as a beam, inducing damage along its track. Our previous study showed that clustered DNA damage yields decreased with increased linear energy transfer (LET), leading us to investigate the importance of clustered DNA damage in the biological effects of heavy ion beam radiation. In this study, we analyzed the yield of clustered base damage (comprising multiple base lesions) in cultured cells irradiated with various heavy ion beams, and investigated isolated base damage and the repair process in post-irradiation cultured cells. Chinese hamster ovary (CHO) cells were irradiated by carbon, silicon, argon and iron ion beams with LETs of 13, 55, 90 and 200 keV µm -1 , respectively. Agarose gel electrophoresis of the cells with enzymatic treatments indicated that clustered base damage yields decreased as the LET increased. The aldehyde reactive probe procedure showed that isolated base damage yields in the irradiated cells followed the same pattern. To analyze the cellular base damage process, clustered DNA damage repair was investigated using DNA repair mutant cells. DNA double-strand breaks accumulated in CHO mutant cells lacking Xrcc1 after irradiation, and the cell viability decreased. On the other hand, mouse embryonic fibroblast (Mef) cells lacking both Nth1 and Ogg1 became more resistant than the wild type Mef. Thus, clustered base damage seems to be involved in the expression of heavy ion beam biological effects via the repair process. (author)

  8. Molecular depth profiling of trehalose using a C{sub 60} cluster ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Wucher, Andreas [Department of Physics, University of Duisburg-Essen, D-47048 Duisburg (Germany)], E-mail: andreas.wucher@uni-due.de; Cheng Juan; Winograd, Nicholas [Department of Chemistry, Pennsylvania State University, University Park, PA 16802 (United States)

    2008-12-15

    Molecular depth profiling of organic overlayers was performed using a mass selected fullerene ion beam in conjunction with time-of-flight (TOF-SIMS) mass spectrometry. The characteristics of depth profiles acquired on a 300-nm trehalose film on Si were studied as a function of the impact kinetic energy and charge state of the C{sub 60} projectile ions. We find that the achieved depth resolution depends only weakly upon energy.

  9. Modification on surface oxide layer structure and surface morphology of niobium by gas cluster ion beam treatments

    International Nuclear Information System (INIS)

    Wu, A.T.; Swenson, D.R.; Insepov, Z.

    2010-01-01

    Recently, it was demonstrated that significant reductions in field emission on Nb surfaces could be achieved by means of a new surface treatment technique called gas cluster ion beam (GCIB). Further study as shown in this paper revealed that GCIB treatments could modify surface irregularities and remove surface asperities leading to a smoother surface finish as demonstrated through measurements using a 3D profilometer, an atomic force microscope, and a scanning electron microscope. These experimental observations were supported by computer simulation via atomistic molecular dynamics and a phenomenological surface dynamics. Measurements employing a secondary ion mass spectrometry found that GCIB could also alter Nb surface oxide layer structure. Possible implications of the experimental results on the performance of Nb superconducting radio frequency cavities treated by GCIB will be discussed. First experimental results on Nb single cell superconducting radio frequency cavities treated by GCIB will be reported.

  10. Reduced sintering of mass-selected Au clusters on SiO2 by alloying with Ti: an aberration-corrected STEM and computational study

    DEFF Research Database (Denmark)

    Niu, Yubiao; Schlexer, Philomena; Sebök, Béla

    2018-01-01

    with a reactive metal, Ti. Mass-selected Au/Ti clusters (400 000 amu) and Au2057 clusters (405 229 amu) were produced with a magnetron sputtering, gas condensation cluster beam source in conjunction with a lateral time-of-flight mass filter, deposited onto a silica support and characterised by XPS and LEIS....... The sintering dynamics of mass-selected Au and Au/Ti alloy nanoclusters were investigated in real space and real time with atomic resolution aberration-corrected HAADF-STEM imaging, supported by model DFT calculations. A strong anchoring effect was revealed in the case of the Au/Ti clusters, because of a much...

  11. 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

  12. 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.)

  13. 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

  14. Development of III-nitride semiconductors by molecular beam epitaxy and cluster beam epitaxy and fabrication of LEDs based on indium gallium nitride MQWs

    Science.gov (United States)

    Chen, Tai-Chou Papo

    The family of III-Nitrides (the binaries InN, GaN, AIN, and their alloys) is one of the most important classes of semiconductor materials. Of the three, Indium Nitride (InN) and Aluminum Nitride (AIN) have been investigated much less than Gallium Nitride (GaN). However, both of these materials are important for optoelectronic infrared and ultraviolet devices. In particular, since InN was found recently to be a narrow gap semiconductor (Eg=0.7eV), its development should extend the applications of nitride semiconductors to the spectral region appropriate to fiber optics communication and photovoltaic applications. Similarly, the development of AIN should lead to deep UV light emitting diodes (LEDs). The first part of this work addresses the evaluation of structural, optical and transport properties of InN films grown by two different deposition methods. In one method, active nitrogen was produced in the form of nitrogen radicals by a radio frequency (RF) plasma-assisted source. In an alternative method, active nitrogen was produced in the form of clusters containing approximately 2000 nitrogen molecules. These clusters were produced by adiabatic expansion from high stagnation pressure through a narrow nozzle into vacuum. The clusters were singly or doubly ionized with positive charge by electron impact and accelerated up to approximately 20 to 25 KV prior to their disintegration on the substrate. Due to the high local temperature produced during the impact of clusters with the substrate, this method is suitable for the deposition of InN at very low temperatures. The films are auto-doped n-type with carrier concentrations varying from 3 x 1018 to 1020 cm-3 and the electron effective mass of these films was determined to be 0.09m0. The majority of the AIN films was grown by the cluster beam epitaxy method and was doped n- and p- type by incorporating silicon (Si) and magnesium (Mg) during the film deposition. All films were grown under Al-rich conditions at relatively

  15. Study of uranium dioxyde sputtering induced by multicharged heavy ions at low and very low kinetic energy: projectile charge effect

    International Nuclear Information System (INIS)

    Haranger, F.

    2003-12-01

    Ion beam irradiation of a solid can lead to the emission of neutral or ionized atoms, molecules or clusters from the surface. This comes as a result of the atomic motion in the vicinity of the surface, induced by the transfer of the projectile energy. Then, the study of the sputtering process appears as a means to get a better understanding of the excited matter state around the projectile trajectory. In the case of slow multicharged ions, a strong electronic excitation can be achieved by the projectile neutralization above the solid surface and / or its deexcitation below the surface. Parallel to this, the slowing down of such ions is essentially related to elastic collision with the target atoms. The study of the effect of the initial charge state of slow multicharged ions, in the sputtering process, has been carried out by measuring the absolute angular distributions of emission of uranium atoms from a uranium dioxide surface. The experiments have been performed in two steps. First, the emitted particles are collected onto a substrate during irradiation. Secondly, the surface of the collectors is analyzed by Rutherford Backscattering Spectrometry (RBS). This method allows the characterization of the emission of neutrals, which are the vast majority of the sputtered particles. The results obtained provide an access to the evolution of the sputtering process as a function of xenon projectile ions charge state. The measurements have been performed over a wide kinetic energy range, from 81 down to 1.5 keV. This allowed a clear separation of the contribution of the kinetic energy and initial projectile charge state to the sputtering phenomenon. (author)

  16. 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.

  17. 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.))

  18. 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

  19. 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.)

  20. 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

  1. FY 2000 report on the results of the research and development project for new industry creation type industrial science technologies. Cluster ion beam process technology; 2000 nendo shinki sangyo soshutsugata sangyo kagaku gijutsu kenkyu kaihatsu seido seika hokokusho. Cluster ion beam process technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Described herein are the FY 2000 results of development of cluster ion beams. This technology generates the strong ion beams of atom and molecule clusters, and irradiate them onto the solid surfaces, to create new materials or treat materials. It allows the nano-level treatment. The program for high-current cluster ion beam generation/irradiation technology for industrial purposes attains the target high-current beam of 500{mu}m. It is necessary to establish the optimum cluster size, irradiated energy and ion species for the highly functional surface treatment, for which applicable technologies, e.g., those related to time of flight and molecular dynamics, are developed. Studies on high-current, large-area irradiation technologies are started. The program for material processing technologies involves evaluation of crystalline defects formed during the beam implantation by photoluminescence spectroscopy, and studies on semiconductor surface processing technologies. The surface smoothening technology is investigated to reduce crystalline defects and stress-induced strains for difficult-to-process materials, e.g., SiC and diamond, and the good results are produced. The program for development of superflat/superhard thin film formation technology involves irradiation of the Ar ion beams during the deposition of C{sub 60}(fullerene), to produce the superhard thin film. (NEDO)

  2. 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

  3. 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.)

  4. Electrostatic solitary waves in current layers: from Cluster observations during a super-substorm to beam experiments at the LAPD

    Science.gov (United States)

    Pickett, J. S.; Chen, L.-J.; Santolík, O.; Grimald, S.; Lavraud, B.; Verkhoglyadova, O. P.; Tsurutani, B. T.; Lefebvre, B.; Fazakerley, A.; Lakhina, G. S.; Ghosh, S. S.; Grison, B.; Décréau, P. M. E.; Gurnett, D. A.; Torbert, R.; Cornilleau-Wehrlin, N.; Dandouras, I.; Lucek, E.

    2009-06-01

    Electrostatic Solitary Waves (ESWs) have been observed by several spacecraft in the current layers of Earth's magnetosphere since 1982. ESWs are manifested as isolated pulses (one wave period) in the high time resolution waveform data obtained on these spacecraft. They are thus nonlinear structures generated out of nonlinear instabilities and processes. We report the first observations of ESWs associated with the onset of a super-substorm that occurred on 24 August 2005 while the Cluster spacecraft were located in the magnetotail at around 18-19 RE and moving northward from the plasma sheet to the lobes. These ESWs were detected in the waveform data of the WBD plasma wave receiver on three of the Cluster spacecraft. The majority of the ESWs were detected about 5 min after the super-substorm onset during which time 1) the PEACE electron instrument detected significant field-aligned electron fluxes from a few 100 eV to 3.5 keV, 2) the EDI instrument detected bursts of field-aligned electron currents, 3) the FGM instrument detected substantial magnetic fluctuations and the presence of Alfvén waves, 4) the STAFF experiment detected broadband electric and magnetic waves, ion cyclotron waves and whistler mode waves, and 5) CIS detected nearly comparable densities of H+ and O+ ions and a large tailward H+ velocity. We compare the characteristics of the ESWs observed during this event to those created in the laboratory at the University of California-Los Angeles Plasma Device (LAPD) with an electron beam. We find that the time durations of both space and LAPD ESWs are only slightly larger than the respective local electron plasma periods, indicating that electron, and not ion, dynamics are responsible for generation of the ESWs. We have discussed possible mechanisms for generating the ESWs in space, including the beam and kinetic Buneman type instabilities and the acoustic instabilities. Future studies will examine these mechanisms in more detail using the space

  5. Electrostatic solitary waves in current layers: from Cluster observations during a super-substorm to beam experiments at the LAPD

    Directory of Open Access Journals (Sweden)

    J. S. Pickett

    2009-06-01

    Full Text Available Electrostatic Solitary Waves (ESWs have been observed by several spacecraft in the current layers of Earth's magnetosphere since 1982. ESWs are manifested as isolated pulses (one wave period in the high time resolution waveform data obtained on these spacecraft. They are thus nonlinear structures generated out of nonlinear instabilities and processes. We report the first observations of ESWs associated with the onset of a super-substorm that occurred on 24 August 2005 while the Cluster spacecraft were located in the magnetotail at around 18–19 RE and moving northward from the plasma sheet to the lobes. These ESWs were detected in the waveform data of the WBD plasma wave receiver on three of the Cluster spacecraft. The majority of the ESWs were detected about 5 min after the super-substorm onset during which time 1 the PEACE electron instrument detected significant field-aligned electron fluxes from a few 100 eV to 3.5 keV, 2 the EDI instrument detected bursts of field-aligned electron currents, 3 the FGM instrument detected substantial magnetic fluctuations and the presence of Alfvén waves, 4 the STAFF experiment detected broadband electric and magnetic waves, ion cyclotron waves and whistler mode waves, and 5 CIS detected nearly comparable densities of H+ and O+ ions and a large tailward H+ velocity. We compare the characteristics of the ESWs observed during this event to those created in the laboratory at the University of California-Los Angeles Plasma Device (LAPD with an electron beam. We find that the time durations of both space and LAPD ESWs are only slightly larger than the respective local electron plasma periods, indicating that electron, and not ion, dynamics are responsible for generation of the ESWs. We have discussed possible mechanisms for generating the ESWs in space, including the beam and kinetic Buneman type instabilities and the acoustic instabilities. Future studies will examine these mechanisms in

  6. 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

  7. On the origin of field-aligned beams at the quasi-perpendicular bow shock: multi-spacecraft observations by Cluster

    Directory of Open Access Journals (Sweden)

    H. Kucharek

    2004-07-01

    Full Text Available Two distinct populations of reflected and accelerated ions are known to originate from quasi-perpendicular shocks, gyrating ions and reflected ion beams. Recent observations under such bow shock conditions with Cluster have shown strong evidence that both particle distributions appear to emerge from the same reflection process. In this paper the basic production mechanism of field-aligned beams has been investigated by using CLUSTER multi-spacecraft measurements. We have analyzed several quasi-perpendicular shocks with the Cluster Ion Spectrometry experiment (CIS and followed the spatial and temporal evolution of the reflected and transmitted ion populations across the shock. These observations show that the field-aligned beams most likely result from effective scattering in pitch angle during reflection in the shock ramp. Investigating a low Mach number shock, leakage of a fraction of the thermalized ion distribution in the downstream region does not appear to be the source as the volume in phase space occupied by beam ions is empty downstream of the shock ramp.

  8. 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

  9. 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)

  10. 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)

  11. Study of MPI based on parallel MOM on PC clusters for EM-beam scattering by 2-D PEC rough surfaces

    International Nuclear Information System (INIS)

    Jun, Ma; Li-Xin, Guo; An-Qi, Wang

    2009-01-01

    This paper firstly applies the finite impulse response filter (FIR) theory combined with the fast Fourier transform (FFT) method to generate two-dimensional Gaussian rough surface. Using the electric field integral equation (EFIE), it introduces the method of moment (MOM) with RWG vector basis function and Galerkin's method to investigate the electromagnetic beam scattering by a two-dimensional PEC Gaussian rough surface on personal computer (PC) clusters. The details of the parallel conjugate gradient method (CGM) for solving the matrix equation are also presented and the numerical simulations are obtained through the message passing interface (MPI) platform on the PC clusters. It finds significantly that the parallel MOM supplies a novel technique for solving a two-dimensional rough surface electromagnetic-scattering problem. The influences of the root-mean-square height, the correlation length and the polarization on the beam scattering characteristics by two-dimensional PEC Gaussian rough surfaces are finally discussed. (classical areas of phenomenology)

  12. Part 1: characterization of beam synthesized catalytic materials. Part 2: further development of molecular SIMS

    International Nuclear Information System (INIS)

    Scheifers, S.M.

    1985-01-01

    Part I of this thesis concerns characterization of catalyst materials prepared by an ion beam implanter and by a multiple expansion cluster source. Ion beam synthesis was carried out on a 250-kev ion implanter. After assembling a special reaction chamber, zeolites were implanted with phosphorous and iron. This work contributed to development of a sputter reactor for ion beam synthesis. Silver catalysts were examined in a reactor designed, built and evaluated for catalysts produced by the sputter reactor and by a multiple expansion cluster source. Small surface area silver foil catalysts and silver cluster catalysts showed kinetic activity for epoxidation of ethylene. Positive results for the small surface area silver cluster catalyst demonstrate the feasibility of studying these catalysts with the special reactor. Part 2 concerns fundamentals and applications of secondary ion mass spectrometry. A data system was implemented for a secondary ion mass spectrometer that involved design and construction of a computer interface. Software routines for the interface were written in assembly language for increased operation efficiency

  13. 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)

  14. Co-deposition of silver nanoclusters and sputtered alumina for sensor devices

    International Nuclear Information System (INIS)

    Schultes, Guenter; Schmidt, Michael; Truar, Marcel; Goettel, Dirk; Freitag-Weber, Olivia; Werner, Ulf

    2007-01-01

    Heterogeneous thin films may be beneficial for sensoring devices. The electrical conductivity of nanoscale metallic particles being embedded in a matrix of non conducting material should exhibit higher sensitivity to mechanical stress and strain compared to homogeneous films. The production of heterogeneous films may follow different routes. This paper describes the attempt to embed Ag nanoclusters emitted from a gas aggregation cluster source into a growing matrix of alumina originating from sputter sources. The characteristics of the cluster source are first resumed, with their mean masses ranging from approx. 1000 to 100,000 atoms per cluster. The expelled and soft landed clusters are extensively examined by transmission electron microscopy verifying their crystalline form. Yet the use of a radio frequency driven sputter source for the embed material destroys and annihilates the Ag clusters even at very low sputter power. If a reactive direct current sputter process is performed within an oxidising sputter gas instead, the Ag clusters are oxidised to different oxides, but they survive as crystalline entities as verified by X-ray diffraction investigations. A simple subsequent heat treatment reduces the Ag oxides to metallic Ag clusters

  15. Cluster-cluster clustering

    International Nuclear Information System (INIS)

    Barnes, J.; Dekel, A.; Efstathiou, G.; Frenk, C.S.; Yale Univ., New Haven, CT; California Univ., Santa Barbara; Cambridge Univ., England; Sussex Univ., Brighton, England)

    1985-01-01

    The cluster correlation function xi sub c(r) is compared with the particle correlation function, xi(r) in cosmological N-body simulations with a wide range of initial conditions. The experiments include scale-free initial conditions, pancake models with a coherence length in the initial density field, and hybrid models. Three N-body techniques and two cluster-finding algorithms are used. In scale-free models with white noise initial conditions, xi sub c and xi are essentially identical. In scale-free models with more power on large scales, it is found that the amplitude of xi sub c increases with cluster richness; in this case the clusters give a biased estimate of the particle correlations. In the pancake and hybrid models (with n = 0 or 1), xi sub c is steeper than xi, but the cluster correlation length exceeds that of the points by less than a factor of 2, independent of cluster richness. Thus the high amplitude of xi sub c found in studies of rich clusters of galaxies is inconsistent with white noise and pancake models and may indicate a primordial fluctuation spectrum with substantial power on large scales. 30 references

  16. 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.)

  17. Observations of the spatial and temporal structure of field-aligned beam and gyrating ring distributions at the quasi-perpendicular bow shock with Cluster CIS

    Directory of Open Access Journals (Sweden)

    E. Möbius

    2001-09-01

    Full Text Available During the early orbit phase, the Cluster spacecraft have repeatedly crossed the perpendicular Earth’s bow shock and provided the first multi-spacecraft measurements. We have analyzed data from the Cluster Ion Spectrometry experiment (CIS, which observes the 3D-ion distribution function of the major species in the energy range of 5 eV to 40 keV with a 4 s resolution. Beams of reflected ions were observed simultaneously at all spacecraft locations and could be tracked from upstream to the shock itself. They were found to originate from the same distribution of ions that constitutes the reflected gyrating ions, which form a ring distribution in the velocity space immediately upstream and downstream of the shock. This observation suggests a common origin of ring and beam populations at quasi-perpendicular shocks in the form of specular reflection and immediate pitch angle scattering. Generally, the spatial evolution across the shock is very similar on all spacecraft, but phased in time according to their relative location. However, a distinct temporal structure of the ion fluxes in the field-aligned beam is observed that varies simultaneously on all spacecraft. This is likely to reflect the variations in the reflection and scattering efficiencies.Key words. Interplanetary physics (planetary bow shocks; energetic particles; instruments and techniques

  18. Interactions of energetic particles and clusters with solids

    International Nuclear Information System (INIS)

    Averback, R.S.; Hsieh, Horngming; Benedek, R.

    1990-12-01

    Ion beams are being applied for surface modifications of materials in a variety of different ways: ion implantation, ion beam mixing, sputtering, and particle or cluster beam-assisted deposition. Fundamental to all of these processes is the deposition of a large amount of energy, generally some keV's, in a localized area. This can lead to the production of defects, atomic mixing, disordering and in some cases, amorphization. Recent results of molecular dynamics computer simulations of energetic displacement cascades in Cu and Ni with energies up to 5 keV suggest that thermal spikes play an important role in these processes. Specifically, it will be shown that many aspects of defect production, atomic mixing and ''cascade collapse'' can be understood as a consequence of local melting of the cascade core. Included in this discussion will be the possible role of electron-phonon coupling in thermal spike dynamics. The interaction of energetic clusters of atoms with solid surfaces has also been studied by molecular dynamics simulations. this process is of interest because a large amount of energy can be deposited in a small region and possibly without creating point defects in the substrate or implanting cluster atoms. The simulations reveal that the dynamics of the collision process are strongly dependent on cluster size and energy. Different regimes where defect production, local melting and plastic flow dominate will be discussed. 43 refs., 7 figs

  19. Carbon dust formation in a cold plasma from cathode sputtering

    International Nuclear Information System (INIS)

    Arnas, C.; Mouberi, A.; Hassouni, K.; Michau, A.; Lombardi, G.; Bonnin, X.; Benedic, F.; Pegourie, B.

    2009-01-01

    Nanoparticles are produced in argon glow plasmas where carbon is introduced by sputtering of a graphite cathode. A scaling law of growth is reported on as a function of the discharge time. Two successive stages of growth of concomitant agglomeration and carbon deposition are observed, followed by a final stage of growth by carbon deposition. A model of formation of molecular precursors by coagulation of neutral clusters on the one hand and of neutral-negative clusters on the other hand is presented, based on formation enthalpy and cluster geometry.

  20. Carbon dust formation in a cold plasma from cathode sputtering

    Science.gov (United States)

    Arnas, C.; Mouberi, A.; Hassouni, K.; Michau, A.; Lombardi, G.; Bonnin, X.; Bénédic, F.; Pégourié, B.

    2009-06-01

    Nanoparticles are produced in argon glow plasmas where carbon is introduced by sputtering of a graphite cathode. A scaling law of growth is reported on as a function of the discharge time. Two successive stages of growth of concomitant agglomeration and carbon deposition are observed, followed by a final stage of growth by carbon deposition. A model of formation of molecular precursors by coagulation of neutral clusters on the one hand and of neutral-negative clusters on the other hand is presented, based on formation enthalpy and cluster geometry.

  1. 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)

  2. 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.)

  3. Binding energy effects in cascade evolution and sputtering

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1995-06-01

    The MARLOWE model was extended to include a binding energy dependent on the local crystalline order, so that atoms are bound less strongly to their lattice sites near surfaces or associated damage. Sputtering and cascade evolution were studied on the examples of self-ion irradiations of Cu and Au monocrystals. In cascades, the mean binding energy is reduced ∼8% in Cu with little dependence on the initial recoil energy; in Au, it is reduced ∼9% at 1 keV and ∼15% at 100 keV. In sputtering, the mean binding energy is reduced ∼8% in Cu and ∼15% in Au with little energy dependence; the yields are increased about half as much. Most sites from which sputtered atoms originate are isolated in both metals. Small clusters of such sites occur in Cu, but there are some large clusters in Au, especially in [111] targets. There are always more large clusters with damage-dependent binding than with a constant binding energy, but only a few clusters are compact enough to be regarded as pits

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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

  11. On the application of the weak-beam technique to the determination of the sizes of small point-defect clusters in ion-irradiated copper

    International Nuclear Information System (INIS)

    Jenkins, M. L.

    1998-01-01

    We have made an analysis of the conditions necessary for the successful use of the weak-beam technique for identifying and characterizing small point-defect clusters in ion-irradiated copper. The visibility of small defects was found to depend only weakly on the magnitude of the beam-convergence. In general, the image sizes of small clusters were found to be most sensitive to the magnitude of Sa with the image sizes of some individual defects changing by large amounts with changes as small as 0.025 nm -1 . The most reliable information on the true defect size is likely to be obtained by taking a series of 5-9 micrographs with a systematic variation of deviation parameter from 0.2-0.3 nm -1 . This procedure allows size information to be obtained down to a resolution limit of about 0.5 nm for defects situated throughout a foil thickness of 60 nm. The technique has been applied to the determination of changes in the sizes of small defects produced by a low-temperature in-situ irradiation and annealing experiment

  12. Laser micromachining of sputtered DLC films

    International Nuclear Information System (INIS)

    Fu, Y.Q.; Luo, J.K.; Flewitt, A.J.; Ong, S.E.; Zhang, S.; Milne, W.I.

    2006-01-01

    DLC films with different thicknesses (from 100 nm to 1.9 μm) were deposited using sputtering of graphite target in pure argon atmosphere without substrate heating. Film microstructures (sp 2 /sp 3 ratio) and mechanical properties (modulus, hardness, stress) were characterized as a function of film thickness. A thin layer of aluminum about 60 nm was deposited on the DLC film surface. Laser micromachining of Al/DLC layer was performed to form microcantilever structures, which were released using a reactive ion etching system with SF 6 plasma. Due to the intrinsic stress in DLC films and bimorph Al/DLC structure, the microcantilevers bent up with different curvatures. For DLC film of 100 nm thick, the cantilever even formed microtubes. The relationship between the bimorph beam bending and DLC film properties (such as stress, modulus, etc.) were discussed in details

  13. Magnetostrictive thin films prepared by RF sputtering

    International Nuclear Information System (INIS)

    Carabias, I.; Martinez, A.; Garcia, M.A.; Pina, E.; Gonzalez, J.M.; Hernando, A.; Crespo, P.

    2005-01-01

    Fe 80 B 20 thin films have been prepared by ion beam sputtering magnetron on room temperature. The films were fabricated on different substrates to compare the different magnetic and structural properties. In particular the growth of films on flexible substrates (PDMS, Kapton) has been studied to allow a simple integration of the system in miniaturized magnetostrictive devices. X-ray diffraction patterns indicate that films are mainly amorphous although the presence of some Fe nanoparticles cannot be ruled out. The coercive field of thin films ranges between 15 and 35 Oe, depending on substrate. Magnetostriction measurements indicate the strong dependence of the saturation magnetostriction with the substrate. Samples on flexible substrates exhibit a better performance than samples deposited onto glass substrates

  14. Ion beams in materials processing and analysis

    CERN Document Server

    Schmidt, Bernd

    2012-01-01

    This book covers ion beam application in modern materials research, offering the basics of ion beam physics and technology and a detailed account of the physics of ion-solid interactions for ion implantation, ion beam synthesis, sputtering and nano-patterning.

  15. Co-sputtered optical films

    Energy Technology Data Exchange (ETDEWEB)

    Misiano, C; Simonetti, E [Selenia S.p.A., Rome (Italy)

    1977-06-01

    The co-sputtering of two dielectric materials with indices of refraction as widely different as possible has been investigated with the aim of obtaining both homogeneous films with an intermediate index of refraction and inhomogeneous films with predetermined profiles. An rf sputtering module is described which has been especially designed, with two separate cathodes and two independent tunable rf generators. The substrates are placed on a circular anode rotating underneath the two cathodes. So far mainly CeO/sub 2/, TiO2 and SiO/sub 2/ targets have been used. The deposition rate from each cathode and the total film thickness are determined by means of two quartz thickness monitors, sputtering compatible. Values obtained for the refractive index and optical thickness are reported, as well as repeatability, mechanical and chemical characteristics, reliability and high power optical radiation resistance. Finally, results obtained on optical components of practical interest are discussed.

  16. Faraday screen sputtering on TPX

    International Nuclear Information System (INIS)

    Ehst, D.A.

    1994-12-01

    The TPX design stipulates that the ion-cyclotron resonance frequency (ICRF) antenna must have a Faraday screen (FS). The author considers here possible low Z coatings for the screen, as well as sputtering behavior of the Ni and Ti substrates. The theory of rf-induced sputtering has been developed, and he follows those theoretical approaches. The author's emphasis will be on both impurity generation as a possible source of increased Z eff , and also on actual erosion-lifetime of the materials under worst case conditions

  17. On niobium sputter coated cavities

    International Nuclear Information System (INIS)

    Arnolds-Mayer, G.; Kaufmann, U.; Downar, H.

    1988-01-01

    To coat copper cavities with a thin film of niobium, facilities for electropolishing and sputter deposition have been installed at Dornier. Experiments have been performed on samples to optimize electropolishing and deposition parameters. In this paper, characteristics concerning surface properties, adhesion of the niobium film to the copper substrate, and film properties were studied on planar samples. A 1.5 GHz single cell cavity made from oxygen free high conductivity (OFHC) copper was sputter coated twice. First rf measurements were performed in the temperature range from 300 K to 2 K

  18. Acceleration of cluster and molecular ions by TIARA 3 MV tandem accelerator

    CERN Document Server

    Saitoh, Y; Tajima, S

    2000-01-01

    We succeeded in accelerating molecular and cluster ions (B sub 2 sub - sub 4 , C sub 2 sub - sub 1 sub 0 , O sub 2 , Al sub 2 sub - sub 4 , Si sub 2 sub - sub 4 , Cu sub 2 sub - sub 3 , Au sub 2 sub - sub 3 , LiF, and AlO) to MeV energies with high-intensity beam currents by means of a 3 MV tandem accelerator in the TIARA facility. These cluster ions were generated by a cesium sputter-type negative ion source. We tested three types of carbon sputter cathodes in which graphite powder was compressed with different pressures. The pressure difference affected the generating ratio of clusters generated to single atom ions extracted from the source and it appeared that the high-density cathode was suitable. We also investigated the optimum gas pressure for charge exchange in the tandem high-voltage terminal. Clusters of larger size tend to require lower pressure than do smaller ones. In addition, we were able to obtain doubly charged AlO molecular ions. (authors)

  19. Cornell electron beam ion source

    International Nuclear Information System (INIS)

    Kostroun, V.O.; Ghanbari, E.; Beebe, E.N.; Janson, S.W.

    1981-01-01

    An electron beam ion source (EBIS) for the production of low energy, multiply charged ion beams to be used in atomic physics experiments has been designed and constructed. An external high perveance electron gun is used to launch the electron beam into a conventional solenoid. Novel features of the design include a distributed sputter ion pump to create the ultrahigh vacuum environment in the ionization region of the source and microprocessor control of the axial trap voltage supplies

  20. Evaluation of biomolecular distributions in rat brain tissues by means of ToF-SIMS using a continuous beam of Ar clusters.

    Science.gov (United States)

    Nakano, Shusuke; Yokoyama, Yuta; Aoyagi, Satoka; Himi, Naoyuki; Fletcher, John S; Lockyer, Nicholas P; Henderson, Alex; Vickerman, John C

    2016-06-08

    Time-of-flight secondary ion mass spectrometry (ToF-SIMS) provides detailed chemical structure information and high spatial resolution images. Therefore, ToF-SIMS is useful for studying biological phenomena such as ischemia. In this study, in order to evaluate cerebral microinfarction, the distribution of biomolecules generated by ischemia was measured with ToF-SIMS. ToF-SIMS data sets were analyzed by means of multivariate analysis for interpreting complex samples containing unknown information and to obtain biomolecular mapping indicated by fragment ions from the target biomolecules. Using conventional ToF-SIMS (primary ion source: Bi cluster ion), it is difficult to detect secondary ions beyond approximately 1000 u. Moreover, the intensity of secondary ions related to biomolecules is not always high enough for imaging because of low concentration even if the masses are lower than 1000 u. However, for the observation of biomolecular distributions in tissues, it is important to detect low amounts of biological molecules from a particular area of tissue. Rat brain tissue samples were measured with ToF-SIMS (J105, Ionoptika, Ltd., Chandlers Ford, UK), using a continuous beam of Ar clusters as a primary ion source. ToF-SIMS with Ar clusters efficiently detects secondary ions related to biomolecules and larger molecules. Molecules detected by ToF-SIMS were examined by analyzing ToF-SIMS data using multivariate analysis. Microspheres (45 μm diameter) were injected into the rat unilateral internal carotid artery (MS rat) to cause cerebral microinfarction. The rat brain was sliced and then measured with ToF-SIMS. The brain samples of a normal rat and the MS rat were examined to find specific secondary ions related to important biomolecules, and then the difference between them was investigated. Finally, specific secondary ions were found around vessels incorporating microspheres in the MS rat. The results suggest that important biomolecules related to cerebral

  1. Influence of ion source configuration and its operation parameters on the target sputtering and implantation process.

    Science.gov (United States)

    Shalnov, K V; Kukhta, V R; Uemura, K; Ito, Y

    2012-06-01

    In the work, investigation of the features and operation regimes of sputter enhanced ion-plasma source are presented. The source is based on the target sputtering with the dense plasma formed in the crossed electric and magnetic fields. It allows operation with noble or reactive gases at low pressure discharge regimes, and, the resulting ion beam is the mixture of ions from the working gas and sputtering target. Any conductive material, such as metals, alloys, or compounds, can be used as the sputtering target. Effectiveness of target sputtering process with the plasma was investigated dependently on the gun geometry, plasma parameters, and the target bias voltage. With the applied accelerating voltage from 0 to 20 kV, the source can be operated in regimes of thin film deposition, ion-beam mixing, and ion implantation. Multi-component ion beam implantation was applied to α-Fe, which leads to the surface hardness increasing from 2 GPa in the initial condition up to 3.5 GPa in case of combined N(2)-C implantation. Projected range of the implanted elements is up to 20 nm with the implantation energy 20 keV that was obtained with XPS depth profiling.

  2. Study of the ion sputter-machining, 1

    International Nuclear Information System (INIS)

    Miyamoto, Iwao; Taniguchi, Norio

    1979-01-01

    A lattice disordering of the surface of single crystal silicon due to ion bombardment of Ar + was investigated by the high energy electron diffraction method, with the incident angle of 1.7 0 and 2.8 0 . By this measuring system, the degree of disorders of the sputter-machined surface layer of Si single crystal in the depth of 50 A and 30 A has been determined, under the working conditions of the ion energy ranging from 0.2 keV to 1.5 keV and the incident angle of ion ranging from 0 0 to 75 0 . Moreover, the recovery of lattice disorder of sputter-machined surface layer of Si single crystal by means of the isochronal thermal annealing has been also confirmed by the same method. From the above experiments, the following conclusions are obtained. (1) The layers of sputter-machined surface of Si single crystal workpiece are highly disordered like amorphous, under the working conditions of ion energy ranging from 0.2 keV to 1.5 keV for the vertical ion incident angle. (2) Under the working conditions of ion incident angle larger than 60 0 , using the ion beam with a lower energy under 300 eV, the surface of the workpiece is not disordered. Therefore, a sputter-machined surface of Si single crystal with highly ordered structure can be obtained under this working condition. (3) The recovery of disorder of sputter-machined surface is completed by the heat-treatment of workpiece under isochronal annealing for 1 hour at 800 0 C. However, it is not clear whether this recovery of lattice point or the dispersion of interstitially located argon atoms from the surface to the outside. (author)

  3. Deuterium sputtering of Li and Li-O films

    Science.gov (United States)

    Nelson, Andrew; Buzi, Luxherta; Kaita, Robert; Koel, Bruce

    2017-10-01

    Lithium wall coatings have been shown to enhance the operational plasma performance of many fusion devices, including NSTX and other tokamaks, by reducing the global wall recycling coefficient. However, pure lithium surfaces are extremely difficult to maintain in experimental fusion devices due to both inevitable oxidation and codeposition from sputtering of hot plasma facing components. Sputtering of thin lithium and lithium oxide films on a molybdenum target by energetic deuterium ion bombardment was studied in laboratory experiments conducted in a surface science apparatus. A Colutron ion source was used to produce a monoenergetic, mass-selected ion beam. Measurements were made under ultrahigh vacuum conditions as a function of surface temperature (90-520 K) using x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and temperature programmed desorption (TPD). Results are compared with computer simulations conducted on a temperature-dependent data-calibrated (TRIM) model.

  4. A current induced diffusion model of gas sputtering

    International Nuclear Information System (INIS)

    Hotston, E.S.

    1980-01-01

    A model is proposed to explain the experimental results on deuteron trapping in stainless steel targets at low temperatures carried out at Garching and Culham. The model proposes that the ions are trapped in two kinds of sites: Deep sites with high activation energy and shallow sites of low activation energy. Trapped deuterons reach the surface of the target by being expelled from shallow sites by the action of the ion beam and migrate to nearby sites in a random way, thus moving by a bombardment induced diffusion. Ions diffusing to the target surface and being released are said to be sputtered from the target. It has been necessary to assume numerical values for sizes of some of the processes which occur. With a suitable choice of values the model successfully predicts the numbers of deuterons trapped per unit area of the target, the obserbed density profile of the trapped ions and the threshold at which sputtering starts. The model also successfully describes the replacement of the trapped deuterons by protons, when the deuteron beam is replaced by a proton beam. The collision cross-section for beam ions and ions trapped in shallow sites is too large, 4 x 10 -13 cm 2 , for a binary collision and it is tentatively suggested that the ions in the shallow sites may be in small voids in the target which may be connected with blister formation. Comparison of the present model with one being developed to describe the trapping of deuterons in carbon suggests that it may be possible to describe all gas sputtering experiments in terms of diffusion processes. (orig.)

  5. Huge increase in gas phase nanoparticle generation by pulsed direct current sputtering in a reactive gas admixture

    Science.gov (United States)

    Polonskyi, Oleksandr; Peter, Tilo; Mohammad Ahadi, Amir; Hinz, Alexander; Strunskus, Thomas; Zaporojtchenko, Vladimir; Biederman, Hynek; Faupel, Franz

    2013-07-01

    Using reactive DC sputtering in a gas aggregation cluster source, we show that pulsed discharge gives rise to a huge increase in deposition rate of nanoparticles by more than one order of magnitude compared to continuous operation. We suggest that this effect is caused by an equilibrium between slight target oxidation (during "time-off") and subsequent sputtering of Ti oxides (sub-oxides) at "time-on" with high power impulse.

  6. Semi-empirical formulas for sputtering yield

    International Nuclear Information System (INIS)

    Yamamura, Yasumichi

    1994-01-01

    When charged particles, electrons, light and so on are irradiated on solid surfaces, the materials are lost from the surfaces, and this phenomenon is called sputtering. In order to understand sputtering phenomenon, the bond energy of atoms on surfaces, the energy given to the vicinity of surfaces and the process of converting the given energy to the energy for releasing atoms must be known. The theories of sputtering and the semi-empirical formulas for evaluating the dependence of sputtering yield on incident energy are explained. The mechanisms of sputtering are that due to collision cascade in the case of heavy ion incidence and that due to surface atom recoil in the case of light ion incidence. The formulas for the sputtering yield of low energy heavy ion sputtering, high energy light ion sputtering and the general case between these extreme cases, and the Matsunami formula are shown. At the stage of the publication of Atomic Data and Nuclear Data Tables in 1984, the data up to 1983 were collected, and about 30 papers published thereafter were added. The experimental data for low Z materials, for example Be, B and C and light ion sputtering data were reported. The combination of ions and target atoms in the collected sputtering data is shown. The new semi-empirical formula by slightly adjusting the Matsunami formula was decided. (K.I.)

  7. Specific power reduction of an ion source due to heating and cathode sputtering of electrodes

    International Nuclear Information System (INIS)

    Hamilton, G.U.; Semashko, N.N.

    The potentialities and limitations of the water-cooled ion-optical system of the ion source designed for continuous operation of the high-power neutral beam injector are determined. The following problems are analyzed: thermal expansion and deformation of electrodes, electrode sputtering as a result of bombardment, and heat transfer to turbulent flow of water

  8. H2 splitting on Pt, Ru and Rh nanoparticles supported on sputtered HOPG

    DEFF Research Database (Denmark)

    Fiordaliso, Elisabetta Maria; Murphy, Shane; Nielsen, R.M.

    2012-01-01

    The equilibrium hydrogen exchange rate between adsorbed and gas phase hydrogen at 1bar is measured for Pt, Ru and Rh nanoparticles supported on a sputtered HOPG substrate. The particles are prepared by Electron Beam Physical Vapor Deposition and the diameter of the particles varies between 2 and ...

  9. Simultaneous study of sputtering and secondary ion emission of binary Fe-based alloys

    International Nuclear Information System (INIS)

    Riadel, M.M.; Nenadovic, T.; Perovic, B.

    1976-01-01

    The sputtering and secondary ion emission of binary Fe-based alloys of simple phase diagrams have been studied simultaneously. A series FeNi and FeCr alloys in the concentration range of 0-100% have been bombarded by 4 keV Kr + ions in a secondary ion mass spectrometer. The composition of the secondary ions has been analysed and also a fraction of the sputtered material has been collected and analysed by electron microprobe. The surface topography of the etched samples has been studied by scanning electron microscope. The relative sputtering coefficients of the metals have been determined, and the preferential sputtering of the alloying component of lower S have been proved. The etching pictures of samples are in correlation with the sputtering rates. Also the degree of secondary ionization has been calculated from the simultaneously measured ion emission and sputtering data. α + shows the change in the concentration range of the melting point minimum. This fact emphasizes the connection between the physico-chemical properties of alloys and their secondary emission process. From the dependence of the emitted homo- and hetero-cluster ions, conclusions could be shown concerning the production mechanism of small metallic aggregates

  10. Hot oxygen atoms: Their generation and chemistry. [Production by sputtering; reaction with butenes

    Energy Technology Data Exchange (ETDEWEB)

    Ferrieri, R.A.; Chu, Yung Y.; Wolf, A.P.

    1987-01-01

    Oxygen atoms with energies between 1 and 10 eV have been produced through ion beam sputtering from metal oxide targets. Argon ion beams were used on Ta/sub 2/O/sub 5/ and V/sub 2/O/sub 5/. Results show that some control may be exerted over the atom's kinetic energy by changing the target. Reactions of the hot O(/sup 3/P) with cis- and trans-butenes were investigated. (DLC)

  11. Molecular dynamic simulation of interaction of low-energy Ar and Xe ions with copper clusters at graphite surface

    International Nuclear Information System (INIS)

    Kornich, G.V.; Lozovskaya, L.I.; Betts, G.; Zaporozhchenko, V.I.; Faupel, F.

    2005-01-01

    One conducted molecular and dynamic simulation of sputtering of isolated clusters consisting of 13, 27 and 195 Cu atoms from the (0001) graphite surface by 200 eV energy Ar and Xe ions. It is shown that the factors of reflection of Ar and Xe ions from copper clusters differ from one another insignificantly, though the energy of the reflected Xe ions is essentially lower than that of Ar ions. The values of the factor of cluster sputtering by Xe ions are higher in contrast to sputtering by Ar ions. One identified two mechanisms of cluster sputtering resulting in the maximum of sputtering intensity at the polar angles near the normal one, and in periodicity of maximums within the azimuth distributions of sputtering intensity with 60 deg period [ru

  12. Depth profiling of superconducting thin films using rare gas ion sputtering with laser postionization

    International Nuclear Information System (INIS)

    Pallix, J.B.; Becker, C.H.; Missert, N.; Char, K.; Hammond, R.H.

    1988-01-01

    Surface analysis by laser ionization (SALI) has been used to examine a high-T/sub c/ superconducting thin film of nominal composition YBa 2 Cu 3 O 7 deposited on SrTiO 3 (100) by reactive magnetron sputtering. The main focus of this work was to probe the compositional uniformity and the impurity content throughout the 1800 A thick film having critical current densities of 1 to 2 x 10 6 A/cm 2 . SALI depth profiles show this film to be more uniform than thicker films (∼1 μm, prepared by electron beam codeposition) which were studied previously, yet the data show that some additional (non-superconducting) phases derived from Y, Ba, Cu, and O are still present. These additional phases are studied by monitoring the atomic and diatomic-oxide photoion profiles and also the depth profiles of various clusters (e.g. Y 2 O 2 + , Y 2 O 3 + , Y 3 O 4 + , Ba 2 O + , Ba 2 O 2 + , BaCu + , BaCuO + , YBaO 2 + , YSrO 2 + , etc.). A variety of impurities are observed to occur throughout the film including rather large concentrations of Sr. Hydroxides, F, Cl, and CO/sub x/ are evident particularly in the sample's near surface region (the top ∼100 A)

  13. Depth profiling of superconducting thin films using rare gas ion sputtering with laser postionization

    Science.gov (United States)

    Pallix, J. B.; Becker, C. H.; Missert, N.; Char, K.; Hammond, R. H.

    1988-02-01

    Surface analysis by laser ionization (SALI) has been used to examine a high-Tc superconducting thin film of nominal composition YBa2Cu3O7 deposited on SrTiO3 (100) by reactive magnetron sputtering. The main focus of this work was to probe the compositional uniformity and the impurity content throughout the 1800 Å thick film having critical current densities of 1 to 2×106 A/cm2. SALI depth profiles show this film to be more uniform than thicker films (˜1 μm, prepared by electron beam codeposition) which were studied previously, yet the data show that some additional (non-superconducting) phases derived from Y, Ba, Cu, and O are still present. These additional phases are studied by monitoring the atomic and diatomic-oxide photoion profiles and also the depth profiles of various clusters (e.g. Y2O2+, Y2O3+, Y3O4+, Ba2O+, Ba2O2+, BaCu+, BaCuO+, YBaO2+, YSrO2+, etc.). A variety of impurities are observed to occur throughout the film including rather large concentrations of Sr. Hydroxides, F, Cl, and COx are evident particularly in the sample's near surface region (the top ˜100 Å).

  14. Exploring the Optical and Morphological Properties of Ag and Ag/TiO2 Nanocomposites Grown by Supersonic Cluster Beam Deposition

    Directory of Open Access Journals (Sweden)

    Emanuele Cavaliere

    2017-12-01

    Full Text Available Nanocomposite systems and nanoparticle (NP films are crucial for many applications and research fields. The structure-properties correlation raises complex questions due to the collective structure of these systems, often granular and porous, a crucial factor impacting their effectiveness and performance. In this framework, we investigate the optical and morphological properties of Ag nanoparticles (NPs films and of Ag NPs/TiO2 porous matrix films, one-step grown by supersonic cluster beam deposition. Morphology and structure of the Ag NPs film and of the Ag/TiO2 (Ag/Ti 50-50 nanocomposite are related to the optical properties of the film employing spectroscopic ellipsometry (SE. We employ a simple Bruggeman effective medium approximation model, corrected by finite size effects of the nano-objects in the film structure to gather information on the structure and morphology of the nanocomposites, in particular porosity and average NPs size for the Ag/TiO2 NP film. Our results suggest that SE is a simple, quick and effective method to measure porosity of nanoscale films and systems, where standard methods for measuring pore sizes might not be applicable.

  15. π-Conjugated organic-based devices with different layered structures produced by the neutral cluster beam deposition method and operating conduction mechanism

    International Nuclear Information System (INIS)

    Seo, Hoon-Seok; Oh, Jeong-Do; Kim, Dae-Kyu; Shin, Eun-Sol; Choi, Jong-Ho

    2012-01-01

    The authors report on the systematic characterization of structural effects of organic complementary inverters based on two π-conjugated organic molecules, pentacene and copper hexadecafluorophthalocyanine (F 16 CuPc). Three classes of inverters with different layered structures in top-contact configuration were produced using the neutral cluster beam deposition method. Their voltage transfer characteristics, gain curves and hysteresis behaviour were characterized with respect to their thickness. Class I inverters, with generic structures of single-layered, p-and n-type (200/180 Å) transistors, exhibited high gains of 12.8 ± 1.0 with sharp inversions. Their two constituent transistors, with hole and electron mobilities of 0.38 cm 2 V -1 s -1 and 7.0 × 10 -3 cm 2 V -1 s -1 , respectively, showed well-coupled carrier conduction during operation. The behaviour of class II and III inverters, with layered heterojunction structures, was independent of upper-layer thickness and did not show hysteresis. The better performances of class II inverters, which showed high gains of 14.4 ± 1.1, were rationalized partly in terms of decreased mobility differences between their constituent transistors. Heterojunction geometries can be applied to obtain high-performance, fast-switching inverters by avoiding direct exposure of the air-sensitive transistors to ambient conditions. The inverters' general operating conduction mechanism is also discussed.

  16. 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

  17. 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%

  18. Iodine Beam Dump Design and Fabrication

    Science.gov (United States)

    Polzin, K. A.; Bradley, D. E.

    2017-01-01

    During the testing of electric thrusters, high-energy ions impacting the walls of a vacuum chamber can cause corrosion and/or sputtering of the wall materials, which can damage the chamber walls. The sputtering can also introduce the constituent materials of the chamber walls into an experiment, with those materials potentially migrating back to the test article and coating it with contaminants over time. The typical method employed in this situation is to install a beam dump fabricated from materials that have a lower sputter yield, thus reducing the amount of foreign material that could migrate towards the test article or deposit on anything else present in the vacuum facility.

  19. Mixed clusters from the coexpansion of C2F6 and n2 in a pulsed, supersonic expansion cluster ion source and beam deflection time-of-flight mass spectrometer: A first application

    Science.gov (United States)

    Thompson, Steven D.

    The following topics are discussed: (1) cluster ion genesis; (2) cluster ion detection; (3) Ion source; (4) pulse valve; (5) e-gun; (6) Ion optics; (7) a first order model; and (8) a modified Bakker's model.

  20. 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

  1. Study of uranium dioxyde sputtering induced by multicharged heavy ions at low and very low kinetic energy: projectile charge effect; Etude de la pulverisation du dioxyde d'uranium induite par des ions lourds multicharges de basse et tres basse energie cinetique; effet de la charge du projectile

    Energy Technology Data Exchange (ETDEWEB)

    Haranger, F

    2003-12-01

    Ion beam irradiation of a solid can lead to the emission of neutral or ionized atoms, molecules or clusters from the surface. This comes as a result of the atomic motion in the vicinity of the surface, induced by the transfer of the projectile energy. Then, the study of the sputtering process appears as a means to get a better understanding of the excited matter state around the projectile trajectory. In the case of slow multicharged ions, a strong electronic excitation can be achieved by the projectile neutralization above the solid surface and / or its deexcitation below the surface. Parallel to this, the slowing down of such ions is essentially related to elastic collision with the target atoms. The study of the effect of the initial charge state of slow multicharged ions, in the sputtering process, has been carried out by measuring the absolute angular distributions of emission of uranium atoms from a uranium dioxide surface. The experiments have been performed in two steps. First, the emitted particles are collected onto a substrate during irradiation. Secondly, the surface of the collectors is analyzed by Rutherford Backscattering Spectrometry (RBS). This method allows the characterization of the emission of neutrals, which are the vast majority of the sputtered particles. The results obtained provide an access to the evolution of the sputtering process as a function of xenon projectile ions charge state. The measurements have been performed over a wide kinetic energy range, from 81 down to 1.5 keV. This allowed a clear separation of the contribution of the kinetic energy and initial projectile charge state to the sputtering phenomenon. (author)

  2. Beam-Beam Effects

    International Nuclear Information System (INIS)

    Herr, W; Pieloni, T

    2014-01-01

    One of the most severe limitations in high-intensity particle colliders is the beam-beam interaction, i.e. the perturbation of the beams as they cross the opposing beams. This introduction to beam-beam effects concentrates on a description of the phenomena that are present in modern colliding beam facilities

  3. Tuning the electronic properties of LaAlO3/SrTiO3 interfaces by irradiating the LaAlO3 surface with low-energy cluster ion beams

    Science.gov (United States)

    Ridier, Karl; Aureau, Damien; Bérini, Bruno; Dumont, Yves; Keller, Niels; Vigneron, Jackie; Etcheberry, Arnaud; Domengès, Bernadette; Fouchet, Arnaud

    2018-01-01

    We have investigated the effects of low-energy ion beam irradiations using argon clusters on the chemical and electronic properties of LaAlO3/SrTiO3 (LAO/STO) heterointerfaces by combining x-ray photoelectron spectroscopy (XPS) and electrical transport measurements. Due to its unique features, we demonstrate that a short-time cluster ion irradiation of the LAO surface induces significant modifications in the chemical properties of the buried STO substrate with (1) a lowering of Ti atoms oxidation states (from Ti4 + to Ti3 + and Ti2 +) correlated to the formation of oxygen vacancies at the LAO surface and (2) the creation of new surface states for Sr atoms. Contrary to what is generally observed by using higher energy ion beam techniques, this leads to an increase of the electrical conductivity at the LAO/STO interface. Our XPS data clearly reveal the existence of dynamical processes on the titanium and strontium atoms, which compete with the effect of the cluster ion beam irradiation. These relaxation effects are in part attributed to the diffusion of the ion-induced oxygen vacancies in the entire heterostructure since an increase of the interfacial metallicity is also evidenced far from the irradiated area. This paper highlights the possibility of tuning the electrical properties of LAO/STO interfaces by surface engineering, confirming experimentally the intimate connection between LAO chemistry and electronic properties of LAO/STO interfaces.

  4. Topography of InP surface bombarded by O2+ ion beam

    International Nuclear Information System (INIS)

    Sun Zhaoqi

    1997-01-01

    The topography of InP surface bombarded by O 2 + ion beam was investigated. Rippled topographies were observed for bombarded samples, and the data show that the ripple formation starts from a sputtering depth of about 0.4 μm. The wavelength and the disorder of the ripples both increase as the sputtering depth increases. The wavelength of the ripples appears to be sputtering depth dependent rather than sputtering rate dependent. It is confirmed that the ion-beam-induced surface rippling can be effectively suppressed by sample rotation during bombardment

  5. Effect of sputtering power on structure and properties of Bi film deposited by DC magnetron sputtering

    International Nuclear Information System (INIS)

    Liao Guo; He Zhibing; Xu Hua; Li Jun; Chen Taihua; Chen Jiajun

    2012-01-01

    Bi film was fabricated at different sputtering powers by DC magnetron sputtering. The deposition rate of Bi film as the function of sputtering power was studied. The surface topography of Bi film was observed by SEM, and the growth mode of Bi film was investigated. The crystal structure was analyzed by XRD. The grain size and stress of Bi film were calculated. The SEM images show that all the films are columnar growth. The average grain size firstly increases as the sputtering power increases, then decreases at 60 W. The film becomes loose with the increase of sputtering power, while, the film gets compact when the sputtering power becomes from 45 to 60 W. The XRD results show that films are polycrystalline of hexagonal. And the stress transforms from the tensile stress to compressive stress as the sputtering power increases. (authors)

  6. Sputtering of octatetraene by 15 keV C{sub 60} projectiles: Comparison of reactive interatomic potentials

    Energy Technology Data Exchange (ETDEWEB)

    Kanski, Michal; Maciazek, Dawid; Golunski, Mikolaj; Postawa, Zbigniew, E-mail: zbigniew.postawa@uj.edu.pl

    2017-02-15

    Highlights: • Probing the effect of interatomic potentials on sputtering of an octatetraene sample. • Problems with charge calculations are observed during cluster impact for ReaxFF. • COMB3 leads to a very low sputtering yield due to abrupt energy dissipation. • AIREBO is computationally the most efficient, while ReaxFF is more accurate. - Abstract: Molecular dynamics computer simulations have been used to probe the effect of the AIREBO, ReaxFF and COMB3 interatomic potentials on sputtering of an organic sample composed of octatetraene molecules. The system is bombarded by a 15 keV C{sub 60} projectile at normal incidence. The effect of the applied force fields on the total time of simulation, the calculated sputtering yield and the angular distribution of sputtered particles is investigated and discussed. It has been found that caution should be taken when simulating particles ejection from nonhomogeneous systems that undergo significant fragmentation described by the ReaxFF. In this case, the charge state of many particles is improper due to an inadequacy of a procedure used for calculating partial charges on atoms in molecules for conditions present during sputtering. A two-step simulation procedure is proposed to minimize the effect of this deficiency. There is also a possible problem with the COMB3 potential, at least at conditions present during cluster impact, as its results are very different from AIREBO or ReaxFF.

  7. Three-dimensional fabrication and characterisation of core-shell nano-columns using electron beam patterning of Ge-doped SiO2

    DEFF Research Database (Denmark)

    Gontard, Lionel C.; Jinschek, Joerg R.; Ou, Haiyan

    2012-01-01

    electron tomography. The results show that transformations in insulators that have been subjected to intense irradiation using charged particles can be studied directly in three dimensions. The fabricated structures include core-shell nano-columns, sputtered regions, voids, and clusters. (C) 2012 American......A focused electron beam in a scanning transmission electron microscope (STEM) is used to create arrays of core-shell structures in a specimen of amorphous SiO2 doped with Ge. The same electron microscope is then used to measure the changes that occurred in the specimen in three dimensions using...

  8. Chemical sputtering of graphite by H+ ions

    International Nuclear Information System (INIS)

    Busharov, N.P.; Gorbatov, E.A.; Gusev, V.M.; Guseva, M.I.; Martynenko, Y.V.

    1976-01-01

    In a study of the sputtering coefficient S for the sputtering of graphite by 10-keV H + ions as a function of the graphite temperature during the bombardment, it is found that at T> or =750degreeC the coefficient S is independent of the target temperature and has an anomalously high value, S=0.085 atom/ion. The high rate of sputtering of graphite by atomic hydrogen ions is shown to be due to chemical sputtering of the graphite, resulting primarily in the formation of CH 4 molecules. At T=1100degreeC, S falls off by a factor of about 3. A model for the chemical sputtering of graphite is proposed

  9. 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.

  10. Measurements of beryllium sputtering yields at JET

    Science.gov (United States)

    Jet-Efda Contributors Stamp, M. F.; Krieger, K.; Brezinsek, S.

    2011-08-01

    The lifetime of the beryllium first wall in ITER will depend on erosion and redeposition processes. The physical sputtering yields for beryllium (both deuterium on beryllium (Be) and Be on Be) are of crucial importance since they drive the erosion process. Literature values of experimental sputtering yields show an order of magnitude variation so predictive modelling of ITER wall lifetimes has large uncertainty. We have reviewed the old beryllium yield experiments on JET and used current beryllium atomic data to produce revised beryllium sputtering yields. These experimental measurements have been compared with a simple physical sputtering model based on TRIM.SP beryllium yield data. Fair agreement is seen for beryllium yields from a clean beryllium limiter. However the yield on a beryllium divertor tile (with C/Be co-deposits) shows poor agreement at low electron temperatures indicating that the effect of the higher sputtering threshold for beryllium carbide is important.

  11. Fundamental properties of secondary negative ion emission by sputtering

    International Nuclear Information System (INIS)

    Shimizu, Toshiki; Tsuji, Hiroshi; Ishikawa, Junzo

    1989-01-01

    The report describes some results obtained from preliminary experiments on secondary negative ion emission from a cesiated surface by Xe-ion beam sputtering, which give the production probability. A measuring system is constructed for secondary negative ion emission. The system consists of a microwave ion source with a lens, a sputtering target holder with a heater, a cesium oven, a limiting aperture with a substrate for deposition, a negative-ion extractor and lens, and a ExB type mass separator. Observations are made on the dependence of negative ion current on cesium supply, dependence of negative ion current on target temperature, and negative ion production probability. The cesium supply and the target temperature are found to strongly influence the negative ion emission. By controlling these factors, the optimum condition for secondary negative ion emission is achieved with a minimum surface work function. The production probability of the negative ion is found to be very high, about 20% for carbon. Therefore, the secondary negative ion emission is considered a useful and highly efficient method to obtain high current ion beams. The constant in the Rasser's theoretical equation is experimentally determined to be 4.1 x 10 -4 eV sec/m. (N.K.)

  12. 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.

  13. Fundamental limits to imaging resolution for focused ion beams

    International Nuclear Information System (INIS)

    Orloff, J.; Swanson, L.W.; Utlaut, M.

    1996-01-01

    This article investigates the limitations on the formation of focused ion beam images from secondary electrons. We use the notion of the information content of an image to account for the effects of resolution, contrast, and signal-to-noise ratio and show that there is a competition between the rate at which small features are sputtered away by the primary beam and the rate of collection of secondary electrons. We find that for small features, sputtering is the limit to imaging resolution, and that for extended small features (e.g., layered structures), rearrangement, redeposition, and differential sputtering rates may limit the resolution in some cases. copyright 1996 American Vacuum Society

  14. Nylon-sputtered nanoparticles: fabrication and basic properties

    Science.gov (United States)

    Polonskyi, O.; Kylián, O.; Solař, P.; Artemenko, A.; Kousal, J.; Slavínská, D.; Choukourov, A.; Biederman, H.

    2012-12-01

    Nylon-sputtered nanoparticles were prepared using a simple gas aggregation cluster source based on a planar magnetron (Haberland type) and equipped with a nylon target. Plasma polymer particles originated in an aggregation chamber and travelled to a main (deposition) chamber with a gas flow through an orifice. The deposited nanoparticles were observed to have a cauliflower-like structure. The nanoparticles were found to be nitrogen-rich with N/C ratio close to 0.5. An increase in rf power from 60 to 100 W resulted in a decrease in mean particle size from 210 to 168 nm whereas an increase in their residence time in the cluster source from 0.7 to 4.6 s resulted in an increase in the size from 73 to 231 nm.

  15. Influence of the atomic structure on the quantum state of sputtered Ir atoms

    International Nuclear Information System (INIS)

    Bastiaansen, J.; Philipsen, V.; Lievens, P.; Silverans, R.E.; Vandeweert, E.

    2004-01-01

    The probability of the ejection of a neutral atom in a specific quantum state after keV-ion beam sputtering is often interpreted in terms of the interaction between the atomic states of the escaping atom and the electronic states of the solid. In this work, we examined this interplay in the sputtering of iridium as this element has--unlike the elements employed in previous investigations--a complex atomic structure due to strong configuration interactions. Double-resonant two-photon laser ionization is used to probe the sputtered Ir atoms yielding information about the probability for an ejected atom to populate a specific atomic state and its escape velocity. The qualitative features of the corresponding population partition and state-selective velocity distributions show the influence of the excitation energy and the electronic structure of the different atomic states. A comparison is made between the experimental data and predictions from the resonant electron transfer description

  16. The mechanism of sputter-induced orientation change in YBCO films on MgO (001)

    International Nuclear Information System (INIS)

    Huang, Y.; Vuchic, B.V.; Baldo, P.; Merkle, K.L.; Buchholz, D.B.; Mahajan, S.; Lei, J.S.; Markworth, P.R.; Chang, R.P.H.

    1996-12-01

    The mechanisms of the sputter-induced orientation change in YBa 2 Cu 3 O 7-x (YBCO) films grown on MgO (001) substrates by pulsed organometallic beam epitaxy (POMBE) are investigated by x-ray diffraction. Rutherford backscatter spectroscopy (RBS), cross-section TEM (XTEM) and microanalysis. It is found that the W atom implantation concurring with the ion sputtering plays an important role in effecting the orientation change. This implantation changes the surface structure of the substrate and induces an intermediate layer in the initial growth of the YBCO film, which in turn acts as a template that induces the orientation change. It seems that the surface morphology change caused by ion sputtering has only a minor effect on the orientation change

  17. Clustering of near clusters versus cluster compactness

    International Nuclear Information System (INIS)

    Yu Gao; Yipeng Jing

    1989-01-01

    The clustering properties of near Zwicky clusters are studied by using the two-point angular correlation function. The angular correlation functions for compact and medium compact clusters, for open clusters, and for all near Zwicky clusters are estimated. The results show much stronger clustering for compact and medium compact clusters than for open clusters, and that open clusters have nearly the same clustering strength as galaxies. A detailed study of the compactness-dependence of correlation function strength is worth investigating. (author)

  18. Observed damage during Argon gas cluster depth profiles of compound semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Barlow, Anders J., E-mail: anders.barlow@ncl.ac.uk; Portoles, Jose F.; Cumpson, Peter J. [National EPSRC XPS Users' Service (NEXUS), School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2014-08-07

    Argon Gas Cluster Ion Beam (GCIB) sources have become very popular in XPS and SIMS in recent years, due to the minimal chemical damage they introduce in the depth-profiling of polymer and other organic materials. These GCIB sources are therefore particularly useful for depth-profiling polymer and organic materials, but also (though more slowly) the surfaces of inorganic materials such as semiconductors, due to the lower roughness expected in cluster ion sputtering compared to that introduced by monatomic ions. We have examined experimentally a set of five compound semiconductors, cadmium telluride (CdTe), gallium arsenide (GaAs), gallium phosphide (GaP), indium arsenide (InAs), and zinc selenide (ZnSe) and a high-κ dielectric material, hafnium oxide (HfO), in their response to argon cluster profiling. An experimentally determined HfO etch rate of 0.025 nm/min (3.95 × 10{sup −2} amu/atom in ion) for 6 keV Ar gas clusters is used in the depth scale conversion for the profiles of the semiconductor materials. The assumption has been that, since the damage introduced into polymer materials is low, even though sputter yields are high, then there is little likelihood of damaging inorganic materials at all with cluster ions. This seems true in most cases; however, in this work, we report for the first time that this damage can in fact be very significant in the case of InAs, causing the formation of metallic indium that is readily visible even to the naked eye.

  19. 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

  20. SiO2-Ta2O5 sputtering yields: simulated and experimental results

    International Nuclear Information System (INIS)

    Vireton, E.; Ganau, P.; Mackowski, J.M.; Michel, C.; Pinard, L.; Remillieux, A.

    1994-09-01

    To improve mirrors coating, we have modeled sputtering of binary oxide targets using TRIM code. First, we have proposed a method to calculate TRIM input parameters using on the one hand thermodynamic cycle and on the other hand Malherbe's results. Secondly, an iterative processing has provided for oxide steady targets caused by ionic bombardment. Thirdly, we have exposed a model to get experimental sputtering yields. Fourthly, for (Ar - SiO 2 ) pair, we have determined that steady target is a silica one. A good agreement between simulated and experimental yields versus ion incident angle has been found. For (Ar - Ta 2 O 5 ) pair, we have to introduce preferential sputtering concept to explain discrepancy between simulation and experiment. In this case, steady target is tantalum monoxide. For (Ar - Ta(+O 2 ) pair, tantalum sputtered by argon ions in reactive oxygen atmosphere, we have to take into account new concept of oxidation stimulated by ion beam. We have supposed that tantalum target becomes a Ta 2 O 5 one in reactive oxygen atmosphere. Then, following mechanism is similar to previous pair. We have obtained steady target of tantalum monoxide too. Comparison between simulated and experimental sputtering yields versus ion incident angle has given very good agreement. By simulation, we have found that tantalum monoxide target has at least 15 angstrom thickness. Those results are compatible with Malherbe's and Taglauer's ones. (authors)

  1. High-power sputtering employed for film deposition

    International Nuclear Information System (INIS)

    Shapovalov, V I

    2017-01-01

    The features of high-power magnetron sputtering employed for the films’ deposition are reviewed. The main physical phenomena accompanying high-power sputtering including ion-electron emission, gas rarefaction, ionization of sputtered atoms, self-sputtering, ion sound waves and the impact of the target heating are described. (paper)

  2. Variables affecting simulated Be sputtering yields

    Energy Technology Data Exchange (ETDEWEB)

    Björkas, C., E-mail: carolina.bjorkas@helsinki.fi; Nordlund, K.

    2013-08-15

    Since beryllium is a strong candidate for the main plasma-facing material in future fusion reactors, its sputtering behaviour plays an important role in predicting the reactor’s life-time. Consensus about the actual sputtering yields has not yet been achieved, as observations are influenced by experimental method and/or studied sample. In this work, the beryllium sputtering due to deuterium and beryllium self-bombardment is analyzed using molecular dynamics simulations. The main methodological aspects that influence the outcome, such as flux and fluence of the bombardment, are highlighted, and it is shown that the simulated yields also depend on the sample structure and deuterium content.

  3. Sensitivity and stability of sputtered sandwich photocells

    International Nuclear Information System (INIS)

    Murray, H.; Piel, A.

    1979-01-01

    The physical parameters of sputtered Metal-Semiconductor-Metal photocells are described in view of solar energy conversion. Specific properties of sputtered films lead to a particular stability of physical parameters such as dark conduction, capacitance and dielectric losses. Interband transitions occur when the photon energy is larger than the bandgap of the photoconductor. The transport of photo-excited carriers in the built-in electric field involves the existence of a photovoltaic effect. The influence of sputtering on the specific properties of solar energy conversion is discussed. (author)

  4. Modeling and analysis of surface roughness effects on sputtering, reflection, and sputtered particle transport

    International Nuclear Information System (INIS)

    Brooks, J.N.; Ruzic, D.N.

    1990-01-01

    The microstructure of the redeposited surface in tokamaks may affect sputtering and reflection properties and subsequent particle transport. This subject has been studied numerically using coupled models/codes for near-surface plasma particle kinetic transport (WBC code) and rough surface sputtering (fractal-TRIM). The coupled codes provide an overall Monte Carlo calculation of the sputtering cascade resulting from an initial flux of hydrogen ions. Beryllium, carbon, and tungsten surfaces are analyzed for typical high recycling, oblique magnetic field, divertor conditions. Significant variations in computed sputtering rates are found with surface roughness. Beryllium exhibits high D-T and self-sputtering coefficients for the plasma regime studied (T e = 30-75 eV). Carbon and tungsten sputtering is significantly lower. 9 refs., 6 figs., 1 tab

  5. Monte Carlo simulations of silicon sputtering by argon ions and an approach for comparison with molecular dynamic results

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-07-01

    Ion beam sputter processes deliver some intrinsic features influencing the growing film properties. Utilisation of these features needs to know how primary ion properties and geometrical process conditions influence the energy and spatial distribution of the sputtered and scattered particles. Beside complex experiments simulations are helpful to explain the correlation between primary parameters and thin film properties. The paper presents first results of two simulation codes with completely different approaches: Monte Carlo (MC) calculations with help of the well known TRIM.SP code and Molecular Dynamics calculations with an in-house developed code. First results of both simulation principles are compared for Argon ion bombardment on a Silicon target. Furthermore, a special experimental setup is outlined for validation of modelling. The setup allows the variation of ion beam parameters (ion species, ion energy, ion incidence angle on the target) and the measurement of the properties of sputtered and scattered particles.

  6. Nanocomposite metal/plasma polymer films prepared by means of gas aggregation cluster source

    Energy Technology Data Exchange (ETDEWEB)

    Polonskyi, O.; Solar, P.; Kylian, O.; Drabik, M.; Artemenko, A.; Kousal, J.; Hanus, J.; Pesicka, J.; Matolinova, I. [Charles University in Prague, Faculty of Mathematics and Physics, V Holesovickach 2, 18000 Prague 8 (Czech Republic); Kolibalova, E. [Tescan, Libusina trida 21, 632 00 Brno (Czech Republic); Slavinska, D. [Charles University in Prague, Faculty of Mathematics and Physics, V Holesovickach 2, 18000 Prague 8 (Czech Republic); Biederman, H., E-mail: bieder@kmf.troja.mff.cuni.cz [Charles University in Prague, Faculty of Mathematics and Physics, V Holesovickach 2, 18000 Prague 8 (Czech Republic)

    2012-04-02

    Nanocomposite metal/plasma polymer films have been prepared by simultaneous plasma polymerization using a mixture of Ar/n-hexane and metal cluster beams. A simple compact cluster gas aggregation source is described and characterized with emphasis on the determination of the amount of charged clusters and their size distribution. It is shown that the fraction of neutral, positively and negatively charged nanoclusters leaving the gas aggregation source is largely influenced by used operational conditions. In addition, it is demonstrated that a large portion of Ag clusters is positively charged, especially when higher currents are used for their production. Deposition of nanocomposite Ag/C:H plasma polymer films is described in detail by means of cluster gas aggregation source. Basic characterization of the films is performed using transmission electron microscopy, ultraviolet-visible and Fourier-transform infrared spectroscopies. It is shown that the morphology, structure and optical properties of such prepared nanocomposites differ significantly from the ones fabricated by means of magnetron sputtering of Ag target in Ar/n-hexane mixture.

  7. The Kansas State University revolving sputter source

    International Nuclear Information System (INIS)

    Tipping, T.N.

    1989-01-01

    It has been that the perfect ion source is one which runs in a very stable mode, runs continuously, and has the ability to change ion species without sacrificing the previous two requirements. This paper presents an approximation to the perfect ion source, the KSU Revolving Sputter Source. The source consists of an Aarhus-geometry sputter source with the addition of a rotating wheel which holds eight sputter cathodes. The wheel consists of a front plate with eight fixed Macor insulators and a back plate with eight Macor insulators held in place by the tension of eight springs. The cathode assembly consists of a copper cartridge with a threaded rod on one end and a sputter cathode with a threaded hole on the back. The cathode is screwed onto the cartridge and the whole assembly may be loaded into the wheel. A small spring on the side of the cartridge holds the assembly in the wheel

  8. Electrical resistivity of sputtered molybdenum films

    International Nuclear Information System (INIS)

    Nagano, J.

    1980-01-01

    The electrical resistivity of r.f. sputtered molybdenum films of thickness 5-150 nm deposited on oxidized silicon substrates was resolved into the three electron scattering components: isotropic background scattering, scattering at grain boundaries and scattering at surfaces. It was concluded that the isotropic background scattering is almost equal to that of bulk molybdenum and is not influenced by sputtering and annealing conditions. When the film thickness is sufficient that surface scattering can be ignored, the decrease in film resistivity after annealing is caused by the decrease in scattering at the grain boundaries for zero bias sputtered films, and is caused by an increase of the grain diameter for r.f. bias sputtered films. (Auth.)

  9. Large Area Sputter Coating on Glass

    Science.gov (United States)

    Katayama, Yoshihito

    Large glass has been used for commercial buildings, housings and vehicles for many years. Glass size for flat displays is getting larger and larger. The glass for the 8th generation is more than 5 m2 in area. Demand of the large glass is increasing not only in these markets but also in a solar cell market growing drastically. Therefore, large area coating is demanded to plus something else on glass more than ever. Sputtering and pyrolysis are the major coating methods on large glass today. Sputtering process is particularly popular because it can deposit a wide variety of materials in good coating uniformity on the glass. This paper describes typical industrial sputtering system and recent progress in sputtering technology. It also shows typical coated glass products in architectural, automotive and display fields and comments on their functions, film stacks and so on.

  10. Spatial distributions of Cu polycrystal sputtered atoms

    International Nuclear Information System (INIS)

    Abgaryan, V.K.; Semenov, A.A.; Shkarban, I.I.

    2004-01-01

    The results of the experimental determination of the Cu atoms spatial distribution, sputtered from the polycrystalline copper target, irradiated by the Xe + ions with the energy of 300 eV, are presented. The spatial distributions of the sputtered particles, calculated through the quasistable-dynamic model of the cascade modeling (CAMO) are presented also for the case of the polycrystalline copper irradiation by the Ar + and Xe + ions with the energy of 300-1000 eV [ru

  11. Sputtering of sodium on the planet Mercury

    Science.gov (United States)

    Mcgrath, M. A.; Johnson, R. E.; Lanzerotti, L. J.

    1986-01-01

    It is shown here that ion sputtering cannot account for the observed neutral sodium vapor column density on Mercury, but that it is an important loss mechanism for Na. Photons are likely to be the dominant stimulus, both directly through photodesorption and indirectly through thermal desorption of absorbed Na. It is concluded that the atmosphere produced is characterized by the planet's surface temperature, with the ion-sputtered Na contributing to a lesser, but more extended, component of the atmosphere.

  12. Heavy particle transport in sputtering systems

    Science.gov (United States)

    Trieschmann, Jan

    2015-09-01

    This contribution aims to discuss the theoretical background of heavy particle transport in plasma sputtering systems such as direct current magnetron sputtering (dcMS), high power impulse magnetron sputtering (HiPIMS), or multi frequency capacitively coupled plasmas (MFCCP). Due to inherently low process pressures below one Pa only kinetic simulation models are suitable. In this work a model appropriate for the description of the transport of film forming particles sputtered of a target material has been devised within the frame of the OpenFOAM software (specifically dsmcFoam). The three dimensional model comprises of ejection of sputtered particles into the reactor chamber, their collisional transport through the volume, as well as deposition of the latter onto the surrounding surfaces (i.e. substrates, walls). An angular dependent Thompson energy distribution fitted to results from Monte-Carlo simulations is assumed initially. Binary collisions are treated via the M1 collision model, a modified variable hard sphere (VHS) model. The dynamics of sputtered and background gas species can be resolved self-consistently following the direct simulation Monte-Carlo (DSMC) approach or, whenever possible, simplified based on the test particle method (TPM) with the assumption of a constant, non-stationary background at a given temperature. At the example of an MFCCP research reactor the transport of sputtered aluminum is specifically discussed. For the peculiar configuration and under typical process conditions with argon as process gas the transport of aluminum sputtered of a circular target is shown to be governed by a one dimensional interaction of the imposed and backscattered particle fluxes. The results are analyzed and discussed on the basis of the obtained velocity distribution functions (VDF). This work is supported by the German Research Foundation (DFG) in the frame of the Collaborative Research Centre TRR 87.

  13. A compact CMA spectrometer with axially integrated hybrid electron-ion gun for ISS, AES and sputter depth profile analysis

    International Nuclear Information System (INIS)

    Gisler, E.; Bas, E.B.

    1986-01-01

    Until now, the combined application of electrons and ions in surface analysis required two separate sources for electrons and ions with different incidence angles. The newly developed hybrid electron-ion gun, however, allows bombardment of the same sample area both with noble gas ions and with electrons coming from the same direction. By integrating such a hybrid gun axially in a cylindrical mirror energy analyser (CMA) a sensitive compact single flange spectrometer obtains for ion scattering spectroscopy (ISS), Auger electron spectroscopy (AES), and sputtering all within normal beam incidence. This concept makes accurate beam centering very easy. Additionally, the bombardment from the same direction both for sputtering and for surface analysis brings advantages in depth profiling. The scattering angle for ISS has a constant value of about 138 0 . The hybrid gun delivers typically an electron beam current of -20μA at 3keV for AES, and an ion beam current of +40 nA and +1.2μA at 2 keV for ISS and sputtering respectively. The switching time between ISS, AES, and sputtering mode is about 0.1 s. So this system is best suited for automatically controlled depth profile analysis. The design and operation of this new system will be described and some applications will be discussed. (author)

  14. Electronic and atomic impacts on large clusters

    International Nuclear Information System (INIS)

    Gspann, J.

    1982-01-01

    Describing first the generation and properties of molecular beams of large Van der Waals clusters such as speed distribution, cluster size distribution, and internal temperature of the clusters, the review then features the results of electronic impacts on large clusters: metastable electronic cluster excitations, ejection of positive cluster ions of less than 100 atoms from much larger parent clusters, and ionization of the large clusters. Atomic impacts at thermal energies are treated with respect to the scattering cross section of the clusters, their drag coefficient in free molecular flow, and the peculiarities of impacts on helium clusters of either isotope. (Auth.)

  15. Sputtering on cobalt with noble gas ions

    International Nuclear Information System (INIS)

    Sarholt-Kristensen, L.; Johansen, A.; Johnson, E.

    1983-01-01

    Single crystals of cobalt have been bombarded with 80 keV Ar + ions and with 80 keV and 200 keV Xe + ions in the [0001] direction of the hcp phase and the [111] direction of the fcc phase. The sputtering yield has been measured as function of target temperature (20 0 C-500 0 C), showing a reduction in sputtering yield for 80 keV Ar + ions and 200 keV Xe + ions, when the crystal structure changes from hcp to fcc. In contrast to this, bombardment with 80 keV Xe + ions results in an increase in sputtering yield as the phase transition is passed. Sputtering yields for [111] nickel are in agreement with the sputtering yields for fcc cobalt indicating normal behaviour of the fcc cobalt phase. The higher sputtering yield of [0001] cobalt for certain combinations of ion mass and energy may then be ascribed to disorder induced partly by martensitic phase transformation, partly by radiation damage. (orig.)

  16. Comparative studies on damages to organic layer during the deposition of ITO films by various sputtering methods

    Science.gov (United States)

    Lei, Hao; Wang, Meihan; Hoshi, Yoichi; Uchida, Takayuki; Kobayashi, Shinichi; Sawada, Yutaka

    2013-11-01

    Aluminum (III) bis(2-methyl-8-quninolinato)-4-phenylphenolate (BAlq) was respectively bombarded and irradiated by Ar ions, oxygen ions, electron beam and ultraviolet light to confirm damages during the sputter-deposition of transparent conductive oxide (TCO) on organic layer. The degree of damage was evaluated by the photoluminescence (PL) spectra of BAlq. The results confirmed the oxygen ions led to a larger damage and were thought to play the double roles of bombardment to organic layer and reaction with organic layer as well. The comparative studies on PL spectra of BAlq after the deposition of TCO films by various sputtering systems, such as conventional magnetron sputtering (MS), low voltage sputtering (LVS) and kinetic-energy-control-deposition (KECD) system, facing target sputtering (FTS) were performed. Relative to MS, LVS and KECD system, FTS can completely suppress the bombardment of the secondary electrons and oxygen negative ions, and keep a higher deposition rate simultaneously, thus it is a good solution to attain a low-damage sputter-deposition.

  17. Comparative studies on damages to organic layer during the deposition of ITO films by various sputtering methods

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Hao, E-mail: haolei@imr.ac.cn [State Key Laboratory for Corrosion and Protection, Division of Surface Engineering of Materials, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Wang, Meihan [College of Mechanical Engineering, Shenyang University, Shenyang 110044 (China); Hoshi, Yoichi; Uchida, Takayuki; Kobayashi, Shinichi; Sawada, Yutaka [Center for Hyper Media Research, Tokyo Polytechnic University, 1583 Iiyama, Atsugi, Kanagawa 243-0297 (Japan)

    2013-11-15

    Aluminum (III) bis(2-methyl-8-quninolinato)-4-phenylphenolate (BAlq) was respectively bombarded and irradiated by Ar ions, oxygen ions, electron beam and ultraviolet light to confirm damages during the sputter-deposition of transparent conductive oxide (TCO) on organic layer. The degree of damage was evaluated by the photoluminescence (PL) spectra of BAlq. The results confirmed the oxygen ions led to a larger damage and were thought to play the double roles of bombardment to organic layer and reaction with organic layer as well. The comparative studies on PL spectra of BAlq after the deposition of TCO films by various sputtering systems, such as conventional magnetron sputtering (MS), low voltage sputtering (LVS) and kinetic-energy-control-deposition (KECD) system, facing target sputtering (FTS) were performed. Relative to MS, LVS and KECD system, FTS can completely suppress the bombardment of the secondary electrons and oxygen negative ions, and keep a higher deposition rate simultaneously, thus it is a good solution to attain a low-damage sputter-deposition.

  18. Multilayer DLC coatings via alternating bias during magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Li Fengji [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore); Zhang, Sam, E-mail: msyzhang@ntu.edu.sg [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore); Kong Junhua [School of Materials Science and Engineering, Nanyang Technological University (Singapore); Zhang Yujuan [Key Laboratory of Special Functional Material, Henan University (China); Zhang Wali [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore)

    2011-05-31

    To combat the high residual stress problem in monolayer diamond-like carbon coatings, this paper fabricated multilayer diamond-like carbon coatings with alternate soft and hard layers via alternating bias during magnetron sputtering. The surface, cross sectional morphology, bonding structures and mechanical properties are investigated. The atomic force microscopy images indicate low bias results in rougher surface with large graphite clusters and voids suggesting low coating density. The multilayered coatings demonstrate relatively smooth surface stemming from higher bias. The cross sectional images from field emission scanning electron microscopy indicate coating thickness decreases as substrate bias increases and confirm that higher bias results in denser coating. Delamination is observed in monolayer coatings due to high residual stress. The trend of sp{sup 3}/sp{sup 2} fraction estimated by X-ray photoelectron spectroscopy is consistent with that of I{sub D}/I{sub G} ratios from Raman spectra, indicating the change of bonding structure with change of substrate bias. Hardness of multilayer diamond-like carbon coating is comparable to the coatings deposited at low constant bias but the adhesion strength and toughness are significantly improved. Alternately biased sputtering deposition provides an alternative when combination of hardness, toughness and adhesion strength is needed in an all diamond-like carbon coating.

  19. 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

  20. Computer simulation of sputtering of graphite target in magnetron sputtering device with two zones of erosion

    Directory of Open Access Journals (Sweden)

    Bogdanov R.V.

    2015-03-01

    Full Text Available A computer simulation program for discharge in a magnetron sputtering device with two erosion zones was developed. Basic laws of the graphite target sputtering process and transport of sputtered material to the substrate were taken into account in the Monte Carlo code. The results of computer simulation for radial distributions of density and energy flux of carbon atoms on the substrate (at different values of discharge current and pressure of the working gas confirmed the possibility of obtaining qualitative homogeneous films using this magnetron sputtering device. Also the discharge modes were determined for this magnetron sputtering device, in which it was possible to obtain such energy and density of carbon atoms fluxes, which were suitable for deposition of carbon films containing carbon nanotubes and other nanoparticles.

  1. A Multi-Sample Cs-Sputter Negative Ion Source

    International Nuclear Information System (INIS)

    Alton, G.D.; Ball, J.A.; Bao, Y.; Cui, B.; Reed, C.A.; Williams, C.

    1998-01-01

    A multi-sample Cs sputter negative-ion source, equipped with a conical-geometry, W-surface-ionizer has been designed and fabricated that permits sample changes without disruption of on-line accelerator operation. Sample changing is effected by actuating an electro-pneumatic control system located at ground potential that drives an air-motor-driven sample-indexing-system mounted at high voltage; this arrangement avoids complications associated with indexing mechanisms that rely on electronic power-supplies located at high potential. In-beam targets are identified by LED indicator lights derived from a fiber-optic, Gray-code target-position sensor. Aspects of the overall source design and details of the indexing mechanism along with operational parameters, ion optics. intensities, and typical emittances for a variety of negative-ion species will be presented in this report

  2. A Multi-Sample Cs-Sputter Negative Ion Source

    Energy Technology Data Exchange (ETDEWEB)

    Alton, G.D.; Ball, J.A.; Bao, Y.; Cui, B.; Reed, C.A.; Williams, C.

    1998-10-05

    A multi-sample Cs sputter negative-ion source, equipped with a conical-geometry, W-surface-ionizer has been designed and fabricated that permits sample changes without disruption of on-line accelerator operation. Sample changing is effected by actuating an electro-pneumatic control system located at ground potential that drives an air-motor-driven sample-indexing-system mounted at high voltage; this arrangement avoids complications associated with indexing mechanisms that rely on electronic power-supplies located at high potential. In-beam targets are identified by LED indicator lights derived from a fiber-optic, Gray-code target-position sensor. Aspects of the overall source design and details of the indexing mechanism along with operational parameters, ion optics. intensities, and typical emittances for a variety of negative-ion species will be presented in this report.

  3. Development of neutral beam source using electron beam excited plasma

    International Nuclear Information System (INIS)

    Hara, Yasuhiro; Hamagaki, Manabu; Mise, Takaya; Hara, Tamio

    2011-01-01

    A low-energy neutral beam (NB) source, which consists of an electron-beam-excited plasma (EBEP) source and two carbon electrodes, has been developed for damageless etching of ultra-large-scale integrated (ULSI) devices. It has been confirmed that the Ar ion beam energy was controlled by the acceleration voltage and the beam profile had good uniformity over the diameter of 80 mm. Dry etching of a Si wafer at the floating potential has been carried out by Ar NB. Si sputtering yield by an Ar NB clearly depends on the acceleration voltage. This result shows that the NB has been generated through the charge exchange reaction from the ion beam in the process chamber. (author)

  4. PREFACE: Nuclear Cluster Conference; Cluster'07

    Science.gov (United States)

    Freer, Martin

    2008-05-01

    The Cluster Conference is a long-running conference series dating back to the 1960's, the first being initiated by Wildermuth in Bochum, Germany, in 1969. The most recent meeting was held in Nara, Japan, in 2003, and in 2007 the 9th Cluster Conference was held in Stratford-upon-Avon, UK. As the name suggests the town of Stratford lies upon the River Avon, and shortly before the conference, due to unprecedented rainfall in the area (approximately 10 cm within half a day), lay in the River Avon! Stratford is the birthplace of the `Bard of Avon' William Shakespeare, and this formed an intriguing conference backdrop. The meeting was attended by some 90 delegates and the programme contained 65 70 oral presentations, and was opened by a historical perspective presented by Professor Brink (Oxford) and closed by Professor Horiuchi (RCNP) with an overview of the conference and future perspectives. In between, the conference covered aspects of clustering in exotic nuclei (both neutron and proton-rich), molecular structures in which valence neutrons are exchanged between cluster cores, condensates in nuclei, neutron-clusters, superheavy nuclei, clusters in nuclear astrophysical processes and exotic cluster decays such as 2p and ternary cluster decay. The field of nuclear clustering has become strongly influenced by the physics of radioactive beam facilities (reflected in the programme), and by the excitement that clustering may have an important impact on the structure of nuclei at the neutron drip-line. It was clear that since Nara the field had progressed substantially and that new themes had emerged and others had crystallized. Two particular topics resonated strongly condensates and nuclear molecules. These topics are thus likely to be central in the next cluster conference which will be held in 2011 in the Hungarian city of Debrechen. Martin Freer Participants and Cluster'07

  5. Electron: Cluster interactions

    International Nuclear Information System (INIS)

    Scheidemann, A.A.; Knight, W.D.

    1994-02-01

    Beam depletion spectroscopy has been used to measure absolute total inelastic electron-sodium cluster collision cross sections in the energy range from E ∼ 0.1 to E ∼ 6 eV. The investigation focused on the closed shell clusters Na 8 , Na 20 , Na 40 . The measured cross sections show an increase for the lowest collision energies where electron attachment is the primary scattering channel. The electron attachment cross section can be understood in terms of Langevin scattering, connecting this measurement with the polarizability of the cluster. For energies above the dissociation energy the measured electron-cluster cross section is energy independent, thus defining an electron-cluster interaction range. This interaction range increases with the cluster size

  6. Structuring of silicon with low energy focused ion beams

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-09-01

    The defect production in silicon induced by focused ion beam irradiation as a function of energy and projectile mass has been investigated and compared to the measured sputter yield. The aim was to find optimal beam parameters for the structuring of semiconductors with a minimum amount of defects produced per removed atom. (author) 2 figs., 2 refs.

  7. Sputtering properties of tungsten 'fuzzy' surfaces

    International Nuclear Information System (INIS)

    Nishijima, D.; Baldwin, M.J.; Doerner, R.P.; Yu, J.H.

    2011-01-01

    Sputtering yields of He-induced W 'fuzzy' surfaces bombarded by Ar have been measured in the linear divertor plasma simulator PISCES-B. It is found that the sputtering yield of a fuzzy surface, Y fuzzy , decreases with increasing fuzzy layer thickness, L, and saturates at ∼10% of that of a smooth surface, Y smooth , at L > 1 μm. The reduction in the sputtering yield is suspected to be due mainly to the porous structure of fuzz, since the ratio, Y fuzzy /Y smooth follows (1 - p fuzz ), where p fuzz is the fuzz porosity. Further, Y fuzzy /Y smooth is observed to increase with incident ion energy, E i . This may be explained by an energy dependent change in the angular distribution of sputtered W atoms, since at lower E i , the angular distribution is observed to become more butterfly-shaped. That is, a larger fraction of sputtered W atoms can line-of-sight deposit/stick onto neighboring fuzz nanostructures for lower E i butterfly distributions, resulting in lower ratio of Y fuzzy /Y smooth .

  8. 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.

  9. 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

  10. Physical sputtering of metallic systems by charged-particle impact

    International Nuclear Information System (INIS)

    Lam, N.Q.

    1989-12-01

    The present paper provides a brief overview of our current understanding of physical sputtering by charged-particle impact, with the emphasis on sputtering of metals and alloys under bombardment with particles that produce knock-on collisions. Fundamental aspects of ion-solid interactions, and recent developments in the study of sputtering of elemental targets and preferential sputtering in multicomponent materials are reviewed. We concentrate only on a few specific topics of sputter emission, including the various properties of the sputtered flux and depth of origin, and on connections between sputtering and other radiation-induced and -enhanced phenomena that modify the near-surface composition of the target. The synergistic effects of these diverse processes in changing the composition of the integrated sputtered-atom flux is described in simple physical terms, using selected examples of recent important progress. 325 refs., 27 figs

  11. 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

  12. Development of a new foil compounded from carbon nanotubes and sputter-deposition carbon

    International Nuclear Information System (INIS)

    Hiroo Hasebe; Hironori Kuboki; Hiroki Okuno; Isao Yamane; Hiroshi Imao; Nobuhisa Fukunishi; Masayuki Kase; Osamu Kamigaito

    2014-01-01

    New carbon-nanotube-sputter-deposition-carbon (CNT-SDC) foils were developed and used in the U beam time at the RIKEN RI Beam Factory (RIBF) from October to December 2011. The lifetimes of these new foils were drastically extended, and stable, high-intensity U beams were successfully provided to users. The lifetime of the CNT-SDC foils was 2-5 C, which was 100 times longer than those of static C-foils previously used. The qualitative analysis of the CNT-SDC foils clearly showed that the CNT structure and bundles were broken by beam irradiation. In addition, it was found that CNT bundles in the CNT-SDC foil were grown after the carbon deposition procedure. This structure was considered to be the reason that the CNT-SDC foils maintain advantages of both CNT and SDC foils. (author)

  13. 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

  14. Sputtering yield calculation for binary target

    International Nuclear Information System (INIS)

    Jimenez-Rodriguez, J.J.; Rodriguez-Vidal, M.; Valles-Abarca, J.A.

    1979-01-01

    The generalization for binary targets, of the ideas proposed by Sigmund for monoatomic targets, leads to a set of coupled intergrodifferential equations for the sputtering functions. After moment decomposition, the final formulae are obtained by the standard method based on the Laplace Transform, where the inverse transform is made with the aid of asymptotic expansions in the limit of very high projectile energy as compared to the surface binding energy. The possible loss of stoichiometry for binary targets is analyzed. Comparison of computed values of sputtering yield for normal incidence, with experimental results shows good agreement. (author)

  15. Photonometers for coating and sputtering machines

    Directory of Open Access Journals (Sweden)

    Václavík J.

    2013-05-01

    Full Text Available The concept of photonometers (alternative name of optical monitor of a vacuum deposition process for coating and sputtering machines is based on photonometers produced by companies like SATIS or HV Dresden. Photometers were developed in the TOPTEC centre and its predecessor VOD (Optical Development Workshop of Institut of Plasma Physics AS CR for more than 10 years. The article describes current status of the technology and ideas which will be incorporated in next development steps. Hardware and software used on coating machines B63D, VNA600 and sputtering machine UPM810 is presented.

  16. Photonometers for coating and sputtering machines

    Science.gov (United States)

    Oupický, P.; Jareš, D.; Václavík, J.; Vápenka, D.

    2013-04-01

    The concept of photonometers (alternative name of optical monitor of a vacuum deposition process) for coating and sputtering machines is based on photonometers produced by companies like SATIS or HV Dresden. Photometers were developed in the TOPTEC centre and its predecessor VOD (Optical Development Workshop of Institut of Plasma Physics AS CR) for more than 10 years. The article describes current status of the technology and ideas which will be incorporated in next development steps. Hardware and software used on coating machines B63D, VNA600 and sputtering machine UPM810 is presented.

  17. Dependence of sputtering coefficient on ion dose

    International Nuclear Information System (INIS)

    Colligon, J.S.; Patel, M.H.

    1977-01-01

    The sputtering coefficient of polycrystalline gold bombarded by 10-40 keV Ar + ions had been measured as a function of total ion dose and shown to exhibit oscillations in magnitude between 30 and 100%. Possible experimental errors which would give rise to such an oscillation have been considered, but it is apparent that these factors are unable to explain the measurements. It is proposed that a change in the Sublimation Energy associated with either bulk damage or formation of surface topographical features arising during ion bombardment may be responsible for the observed variations in sputtering coefficient. (author)

  18. Carbonaceous Particles Production in a Sputtering Discharge

    International Nuclear Information System (INIS)

    Dominique, Claire; Sant, Marco; Arnas, Cecile

    2005-01-01

    Spherical dust particles have been produced in argon glow discharge by sputtering of a graphite cathode. Their size varies from 40 to 200 nm depending on the distance between the two electrodes and the largest ones have a cauliflower shape. Simulations giving the evolution of the energy distribution of sputtered carbon atoms suggest a mechanism of growth by carbon vapour condensation. The chemical composition and structure of particles have been investigated by infrared spectroscopy and appear to be a complex arrangement of the carbon atoms and hetero-atoms

  19. Heavy ion irradiation of crystalline water ice. Cosmic ray amorphisation cross-section and sputtering yield

    Science.gov (United States)

    Dartois, E.; Augé, B.; Boduch, P.; Brunetto, R.; Chabot, M.; Domaracka, A.; Ding, J. J.; Kamalou, O.; Lv, X. Y.; Rothard, H.; da Silveira, E. F.; Thomas, J. C.

    2015-04-01

    Context. Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. Aims: We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. Methods: We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). Results: The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic stopping power. Conclusions: The final state of cosmic ray irradiation for porous amorphous and crystalline ice, as monitored by infrared spectroscopy, is the same, but with a large difference in cross-section, hence in time scale in an astrophysical context. The cosmic ray water-ice sputtering rates compete with the UV photodesorption yields reported in the literature. The prevalence of direct cosmic ray sputtering over cosmic-ray induced photons photodesorption may be particularly true for ices strongly bonded to the ice mantles surfaces, such as hydrogen-bonded ice structures or more generally the so-called polar ices. Experiments performed at the Grand Accélérateur National d'Ions Lourds (GANIL) Caen, France. Part of this work has been financed by the French INSU-CNRS programme "Physique et Chimie du Milieu Interstellaire" (PCMI) and the ANR IGLIAS.

  20. 14th international symposium on molecular beams

    Energy Technology Data Exchange (ETDEWEB)

    1992-09-01

    This report discusses research being conducted with molecular beams. The general topic areas are as follows: Clusters I; reaction dynamics; atomic and molecular spectroscopy; clusters II; new techniques; photodissociation & dynamics; and surfaces.

  1. 14th international symposium on molecular beams

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This report discusses research being conducted with molecular beams. The general topic areas are as follows: Clusters I; reaction dynamics; atomic and molecular spectroscopy; clusters II; new techniques; photodissociation dynamics; and surfaces.

  2. 14th international symposium on molecular beams

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses research being conducted with molecular beams. The general topic areas are as follows: Clusters I; reaction dynamics; atomic and molecular spectroscopy; clusters II; new techniques; photodissociation ampersand dynamics; and surfaces

  3. KRYPTON INCORPORATION IN SPUTTERED SILICON FILMS

    NARCIS (Netherlands)

    GREUTER, MJW; NIESEN, L; HAKVOORT, RA; DEROODE, J; VANVEEN, A; BERNTSEN, AJM; SLOOF, WG

    1993-01-01

    The incorporation of Kr in sputtered a-Si films has been investigated in a systematic way by varying the Kr to Si flux, yielding Kr concentrations up to 5 at %. Compositions were determined with X-ray microanalysis. A model has been applied to describe the composition of the growing film. The layers

  4. Lithium insertion in sputtered vanadium oxide film

    DEFF Research Database (Denmark)

    West, K.; Zachau-Christiansen, B.; Skaarup, S.V.

    1992-01-01

    were oxygen deficient compared to V2O5. Films prepared in pure argon were reduced to V(4) or lower. The vanadium oxide films were tested in solid-state lithium cells. Films sputtered in oxygen showed electrochemical properties similar to crystalline V2O5. The main differences are a decreased capacity...

  5. Tungsten self-sputtering yield with different incidence angles and target temperatures

    International Nuclear Information System (INIS)

    Bandourko, V.; Nakamura, K.; Akiba, M.; Jimbou, R.

    1998-01-01

    The self-sputtering of different types of tungsten due to 1 keV W + bombardment at temperatures of 25 C and 600 C and incident angles in the range of 30-60 was studied by means of the weight loss method. The experimental data at room temperature agreed reasonably with the results of TRIM calculations. Enhanced self-sputtering yields due to beam-induced desorption of WO 2 were found at a temperature of 600 C. The weight loss of W-Cu composite is larger than that of the CVD-W and ps-W under the same irradiation conditions due to the selective removal of copper. (orig.)

  6. Raman spectroscopy of sputtered metal-graphene and metal-oxide-graphene interfaces

    Science.gov (United States)

    Chen, Ching-Tzu; Gajek, Marcin; Freitag, Marcus; Kuroda, Marcelo; Perebeinos, Vasili; Raoux, Simone

    2012-02-01

    In this talk, we report our recent development in sputtering deposition of magnetic and non-magnetic metal and metal-oxide thin films on graphene for applications in spintronics and nanoeleoctronics. TEM and SEM images demonstrate homogeneous coverage, uniform thickness, and good crystallinity of the sputtered films. Raman spectroscopy shows that the structure of the underlying graphene is well preserved, and the spectral weight of the defect D mode is comparable to that of the e-beam evaporated samples. Most significantly, we report the first observation of graphene-enhanced surface excitations of crystalline materials. Specifically, we discover two pronounced dispersive Raman modes at the interface of graphene and the nickel-oxide and cobalt-oxide films which we attribute to the strong light absorption and high-order resonant scattering process in the graphene layer. We will present the frequency-dependent, polarization-dependent Raman data of these two modes and discuss their microscopic origin.

  7. 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

  8. Near band edge emission characteristics of sputtered nano-crystalline ZnO films

    International Nuclear Information System (INIS)

    Kunj, Saurabh; Sreenivas, K.

    2016-01-01

    Sputtered zinc oxide (ZnO) thin films deposited on unheated glass substrate under different sputtering gas mixtures (Ar+O_2) have been investigated using X-ray diffraction and photo luminescence spectroscopy. Earlier reported studies on ZnO films prepared by different techniques exhibit either a sharp/broad near band edge (NBE) emission peak depending on the crystalline quality of the film. In the present study zinc oxide films, grown on unheated substrates, are seen to possess a preferred (002) orientation with a microstructure consisting of clustered nano-sized crystallites. The splitting in the near band edge emission (NBE) into three characteristic peaks is attributed to quantum confinement effect, and is observed specifically under an excitation of 270 nm. Deep level emission (DLE) in the range 400 to 700 nm is not observed indicating absence of deep level radiative defects.

  9. Near band edge emission characteristics of sputtered nano-crystalline ZnO films

    Science.gov (United States)

    Kunj, Saurabh; Sreenivas, K.

    2016-05-01

    Sputtered zinc oxide (ZnO) thin films deposited on unheated glass substrate under different sputtering gas mixtures (Ar+O2) have been investigated using X-ray diffraction and photo luminescence spectroscopy. Earlier reported studies on ZnO films prepared by different techniques exhibit either a sharp/broad near band edge (NBE) emission peak depending on the crystalline quality of the film. In the present study zinc oxide films, grown on unheated substrates, are seen to possess a preferred (002) orientation with a microstructure consisting of clustered nano-sized crystallites. The splitting in the near band edge emission (NBE) into three characteristic peaks is attributed to quantum confinement effect, and is observed specifically under an excitation of 270 nm. Deep level emission (DLE) in the range 400 to 700 nm is not observed indicating absence of deep level radiative defects.

  10. Near band edge emission characteristics of sputtered nano-crystalline ZnO films

    Energy Technology Data Exchange (ETDEWEB)

    Kunj, Saurabh; Sreenivas, K. [Department of Physics & Astrophysics, University of Delhi, Delhi 110007 INDIA (India)

    2016-05-06

    Sputtered zinc oxide (ZnO) thin films deposited on unheated glass substrate under different sputtering gas mixtures (Ar+O{sub 2}) have been investigated using X-ray diffraction and photo luminescence spectroscopy. Earlier reported studies on ZnO films prepared by different techniques exhibit either a sharp/broad near band edge (NBE) emission peak depending on the crystalline quality of the film. In the present study zinc oxide films, grown on unheated substrates, are seen to possess a preferred (002) orientation with a microstructure consisting of clustered nano-sized crystallites. The splitting in the near band edge emission (NBE) into three characteristic peaks is attributed to quantum confinement effect, and is observed specifically under an excitation of 270 nm. Deep level emission (DLE) in the range 400 to 700 nm is not observed indicating absence of deep level radiative defects.

  11. Cluster headache

    Science.gov (United States)

    Histamine headache; Headache - histamine; Migrainous neuralgia; Headache - cluster; Horton's headache; Vascular headache - cluster ... Doctors do not know exactly what causes cluster headaches. They ... (chemical in the body released during an allergic response) or ...

  12. Preparation and electrical-property characterization of poly(vinyl chloride)-derived carbon nanosheet by ion beam irradiation-induced carbon clustering and carbonization

    Science.gov (United States)

    Jung, Chan-Hee; Sohn, Joon-Yong; Kim, Hyo-Sub; Hwang, In-Tae; Lee, Hong-Joon; Shin, Junhwa; Choi, Jae-Hak

    2018-05-01

    In this work, we demonstrated that carbon nanosheet (CNS) can easily be produced by a room-temperature, solid-state proton irradiation-induced clustering of poly(vinyl chloride) (PVC) films followed by carbonization. The results of the optical, chemical, and structural analyses revealed that oxidized and sp2-hybridized carbon clusters were effectively created in the PVC thin film by combined dehydrochlorination and inter-coupling reactions during proton irradiation. This was further converted to pseudo-hexagonally-structured nano-crystalline CNS with 2-D symmetry and metallic transporting character by high-temperature treatment. As a result, the CNS exhibited a very high electrical conductivity (587 S/cm) without a significant change in their thickness, a low surface roughness (0.36 nm), and a high work function (5.11 eV). These findings demonstrate that the radiation-based approach opens new avenues for the design and development of 2-D CNS as a graphene allotrope for the application of electronic devices, including field-effect transistors, electric heating devices, biosensors, supercapacitors, and fuel cells.

  13. 2n-emission from {sup 205}Pb* nucleus using clusterization approach at E{sub beam}∼14-20 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Amandeep, E-mail: adeepkaur89@gmail.com; Sandhu, Kiran; Sharma, Manoj Kumar, E-mail: msharma@thapar.edu [School of Physics and Materials Science, Thapar University, Patiala-147004, Punjab (India)

    2016-05-06

    The dynamics involved in n-induced reaction with {sup 204}Pb target is analyzed and the decay of the composite system {sup 205}Pb* is governed within the collective clusterization approach of the Dynamical Cluster-decay Model (DCM). The experimental data for 2n-evaporation channel is available for neutron energy range of 14-20 MeV and is addressed by optimizing the only parameter of the model, the neck-length parameter (ΔR). The calculations are done by taking the quadrupole (β{sub 2}) deformations of the decaying fragments and the calculated 2n-emission cross-sections find nice agreement with available data. An effort is made to study the role of level density parameter in the decay of hot-rotating nucleus, and the mass dependence in level density parameter is exercised for the first time in DCM based calculations. It is to be noted that the effect of deformation, temperature and angular momentum etc. is studied to extract better description of the dynamics involved.

  14. 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.

  15. 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

  16. Transport theory of sputtering I: Depth of origin of sputtered atoms

    International Nuclear Information System (INIS)

    Zhang, Z.L.

    1999-01-01

    Sputter theory employing a sum of two power cross sections has been implemented. Compared with the well known Lindhard power cross section (V∝r -1/m ), a sum of two such cross sections can give a much better approximation to the Born-Mayer scattering in the low energy region (m ∼ 0.1). By using both one and two power cross sections, we have solved the linear transport equations describing the sputtering problem asymptotically. As usual, electronic stopping is ignored in the analysis. It has further been proved that Falcone's theory of the atom ejection process contradicts transport theory. The Andersen-Sigmund relation for partial sputtering yield ratios between two elements in an arbitrary multicomponent target has been derived by both methods. The energy deposited in the target surface layers has been computed for a few typical ion-target combinations. The numerical curves show that both theories generate almost the same results (error <10%) for m=3D0.2. It is also shown that, if the sputtering yield equals the corresponding one in Sigmund's theory, the depth of origin of sputtered atoms must be shorter than in Sigmund's theory for 0.25 m ≥ 3D 0. The former even may be only about one half of the latter as long as m=3D0. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  17. 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

  18. Niobium sputter deposition on quarter wave resonators

    CERN Document Server

    Viswanadham, C; Jayaprakash, D; Mishra, R L

    2003-01-01

    Niobium sputter deposition on quarter wave copper R.F resonators, have been taken up in our laboratory, An ultra high vacuum system was made for this purpose. Niobium exhibits superconducting properties at liquid Helium temperature. A uniform coating of about 1.5 mu m of niobium on the internal surfaces of the copper resonant cavities is desired. Power dissipation in the resonators can be greatly reduced by making the internal surfaces of the R.F cavity super conducting. (author)

  19. Sputter coating of microspherical substrates by levitation

    Science.gov (United States)

    Lowe, A.T.; Hosford, C.D.

    Microspheres are substantially uniformly coated with metals or nonmetals by simltaneously levitating them and sputter coating them at total chamber pressures less than 1 torr. A collimated hole structure comprising a parallel array of upwardly projecting individual gas outlets is machined out to form a dimple. Glass microballoons,, which are particularly useful in laser fusion applications, can be substantially uniformly coated using the coating method and apparatus.

  20. Origins of Beta Tantalum in Sputtered Coatings

    National Research Council Canada - National Science Library

    Mulligan, C

    2001-01-01

    .... Some of the most recent work has attempted to relate the energetics (i.e., atom/ion energy) of the plasma to the alpha right arrow beta transition. It has been shown that the energetics of the plasma can relate to the most crucial sputtering parameters. The most significant feature of the use of plasma energy to explain the alpha right arrow beta transition is that it relates the formation of beta-tantalum to a quantifiable measure.

  1. Scaling in patterns produces by cluster deposition

    DEFF Research Database (Denmark)

    Kyhle, Anders; Sørensen, Alexis Hammer; Oddershede, Lene

    1997-01-01

    Cluster deposition on flat substrates can lead to surprising patterns. This pattern formation can be related either to phenomena taking place at the substrate surface or to dynamics in the cluster beam. We describe the observation of a pattern of particles each being an aggregate of Cu clusters. ...

  2. Epitaxial growth of rhenium with sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Seongshik [National Institute of Standards and Technology, Boulder, CO 80305 (United States) and Department of Physics, University of Illinois, Urbana, IL 61801 (United States)]. E-mail: soh@boulder.nist.gov; Hite, Dustin A. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Cicak, K. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Osborn, Kevin D. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Simmonds, Raymond W. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); McDermott, Robert [University of California, Santa Barbara, CA 93106 (United States); Cooper, Ken B. [University of California, Santa Barbara, CA 93106 (United States); Steffen, Matthias [University of California, Santa Barbara, CA 93106 (United States); Martinis, John M. [University of California, Santa Barbara, CA 93106 (United States); Pappas, David P. [National Institute of Standards and Technology, Boulder, CO 80305 (United States)

    2006-02-21

    We have grown epitaxial Rhenium (Re) (0001) films on {alpha}-Al{sub 2}O{sub 3} (0001) substrates using sputter deposition in an ultra high vacuum system. We find that better epitaxy is achieved with DC rather than with RF sputtering. With DC sputtering, epitaxy is obtained with the substrate temperatures above 700 deg. C and deposition rates below 0.1 nm/s. The epitaxial Re films are typically composed of terraced hexagonal islands with screw dislocations, and island size gets larger with high temperature post-deposition annealing. The growth starts in a three dimensional mode but transforms into two dimensional mode as the film gets thicker. With a thin ({approx}2 nm) seed layer deposited at room temperature and annealed at a high temperature, the initial three dimensional growth can be suppressed. This results in larger islands when a thick film is grown at 850 deg. C on the seed layer. We also find that when a room temperature deposited Re film is annealed to higher temperatures, epitaxial features start to show up above {approx}600 deg. C, but the film tends to be disordered.

  3. Beam, multi-beam and broad beam production with COMIC devices

    International Nuclear Information System (INIS)

    Sortais, P.; Lamy, T.; Medard, J.; Angot, J.; Peaucelle, C.

    2012-01-01

    The COMIC discharge cavity is a very versatile technology. We will present new results and devices that match new applications like: molecular beams, ultra compact beam line for detectors calibrations, quartz source for on-line application, high voltage platform source, sputtering /assistance broad beams and finally, a quite new use, high energy multi-beam production for surface material modifications. In more details, we will show that the tiny discharge of COMIC can mainly produce molecular ions (H 3+ ). We will present the preliminary operation of the fully quartz ISOLDE COMIC version, in collaboration with IPN Lyon, we will present a first approach for a slit extraction version of a three cavity device, and after discussing about various extraction systems on the multi discharge device (41 cavities) we will show the low energy broad beam (2 KV) and high energy multi-beams (10 beams up to 30 KV) productions. We will specially present the different extraction systems adapted to each application and the beams characteristics which are strongly dependent on the voltage distribution of an accel-accel two electrodes extraction system. The paper is followed by the slides of the presentation. (authors)

  4. 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.)

  5. On the topography of sputtered or chemically etched crystals: surface energies minimised

    International Nuclear Information System (INIS)

    Chadderton, L.T.; Cope, J.O.

    1984-01-01

    The sputtering of single or polycrystalline metal surfaces by heavy ions gives rise to the characteristic topographical features of etch pits, ripples, and cones (pyramids). For cones and pyramids, in particular, no completely satisfactory explanation exists as to the origin of the basic geometry. Scanning electron micrographs are shown. It is proposed that for topographical features of both chemical etch and ion beam origin on single crystal surfaces, the presence of facets on cones and pyramids in particular, is due to the minimization of surface energy. (U.K.)

  6. Beam-beam phenomenology

    International Nuclear Information System (INIS)

    Teng, L.C.

    1980-01-01

    In colliding beam storage rings the beam collision regions are generally so short that the beam-beam interaction can be considered as a series of evenly spaced non-linear kicks superimposed on otherwise stable linear oscillations. Most of the numerical studies on computers were carried out in just this manner. But for some reason this model has not been extensively employed in analytical studies. This is perhaps because all analytical work has so far been done by mathematicians pursuing general transcendental features of non-linear mechanics for whom this specific model of the specific system of colliding beams is too parochial and too repugnantly physical. Be that as it may, this model is of direct interest to accelerator physicists and is amenable to (1) further simplification, (2) physical approximation, and (3) solution by analogy to known phenomena

  7. RHEED oscillations in spinel ferrite epitaxial films grown by conventional planar magnetron sputtering

    Science.gov (United States)

    Ojima, T.; Tainosho, T.; Sharmin, S.; Yanagihara, H.

    2018-04-01

    Real-time in situ reflection high energy electron diffraction (RHEED) observations of Fe3O4, γ-Fe2O3, and (Co,Fe)3O4 films on MgO(001) substrates grown by a conventional planar magnetron sputtering was studied. The change in periodical intensity of the specular reflection spot in the RHEED images of three different spinel ferrite compounds grown by two different sputtering systems was examined. The oscillation period was found to correspond to the 1/4 unit cell of each spinel ferrite, similar to that observed in molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) experiments. This suggests that the layer-by-layer growth of spinel ferrite (001) films is general in most physical vapor deposition (PVD) processes. The surfaces of the films were as flat as the surface of the substrate, consistent with the observed layer-by-layer growth process. The observed RHEED oscillation indicates that even a conventional sputtering method can be used to control film thickness during atomic layer depositions.

  8. 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)

  9. Spectroellipsometric detection of silicon substrate damage caused by radiofrequency sputtering of niobium oxide

    Science.gov (United States)

    Lohner, Tivadar; Serényi, Miklós; Szilágyi, Edit; Zolnai, Zsolt; Czigány, Zsolt; Khánh, Nguyen Quoc; Petrik, Péter; Fried, Miklós

    2017-11-01

    Substrate surface damage induced by deposition of metal atoms by radiofrequency (rf) sputtering or ion beam sputtering onto single-crystalline silicon (c-Si) surface has been characterized earlier by electrical measurements. The question arises whether it is possible to characterize surface damage using spectroscopic ellipsometry (SE). In our experiments niobium oxide layers were deposited by rf sputtering on c-Si substrates in gas mixture of oxygen and argon. Multiple angle of incidence spectroscopic ellipsometry measurements were performed, a four-layer optical model (surface roughness layer, niobium oxide layer, native silicon oxide layer and ion implantation-amorphized silicon [i-a-Si] layer on a c-Si substrate) was created in order to evaluate the spectra. The evaluations yielded thicknesses of several nm for the i-a-Si layer. Better agreement could be achieved between the measured and the generated spectra by inserting a mixed layer (with components of c-Si and i-a-Si applying the effective medium approximation) between the silicon oxide layer and the c-Si substrate. High depth resolution Rutherford backscattering (RBS) measurements were performed to investigate the interface disorder between the deposited niobium oxide layer and the c-Si substrate. Atomic resolution cross-sectional transmission electron microscopy investigation was applied to visualize the details of the damaged subsurface region of the substrate.

  10. Stress evolution during and after sputter deposition of thin Cu Al alloy films

    Science.gov (United States)

    Pletea, M.; Wendrock, H.; Kaltofen, R.; Schmidt, O. G.; Koch, R.

    2008-06-01

    The stress evolution during and after sputter deposition of thin Cu-Al alloy films containing 1 and 2 at.% Al onto oxidized Si(100) substrates has been studied up to thicknesses of 300 nm by means of in situ substrate curvature measurements. In order to correlate stress and morphology, the microstructure was investigated by focused ion beam microscopy, scanning electron microscopy, and atomic force microscopy. The evolution of the stress and microstructure of the Cu-Al alloy films is similar to that for sputtered pure Cu films. Film growth proceeds in the Volmer-Weber mode, typical for high mobility metals. It is characterized by nucleation, island, percolation, and channel stages before the films become continuous, as well as lateral grain growth in the compact films. With increasing Al content the overall atom mobility and, thus, the average grain size of the alloy films are reduced. Increase of the sputter pressure from 0.5 to 2 Pa leads to films with larger grain size, rougher surface morphology and higher electrical resistivity.

  11. RHEED oscillations in spinel ferrite epitaxial films grown by conventional planar magnetron sputtering

    Directory of Open Access Journals (Sweden)

    T. Ojima

    2018-04-01

    Full Text Available Real-time in situ reflection high energy electron diffraction (RHEED observations of Fe3O4, γ-Fe2O3, and (Co,Fe3O4 films on MgO(001 substrates grown by a conventional planar magnetron sputtering was studied. The change in periodical intensity of the specular reflection spot in the RHEED images of three different spinel ferrite compounds grown by two different sputtering systems was examined. The oscillation period was found to correspond to the 1/4 unit cell of each spinel ferrite, similar to that observed in molecular beam epitaxy (MBE and pulsed laser deposition (PLD experiments. This suggests that the layer-by-layer growth of spinel ferrite (001 films is general in most physical vapor deposition (PVD processes. The surfaces of the films were as flat as the surface of the substrate, consistent with the observed layer-by-layer growth process. The observed RHEED oscillation indicates that even a conventional sputtering method can be used to control film thickness during atomic layer depositions.

  12. Sputtering from swift-ion trails in LiF: A hybrid PIC/MD simulation

    Energy Technology Data Exchange (ETDEWEB)

    Cherednikov, Yaroslav; Sun, Si Neng; Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de

    2013-11-15

    We model the sputtering of a LiF crystal induced by swift-ion impact. The impinging ion creates a trail of doubly ionized F{sup +} ions, while simultaneously the corresponding electrons are set free. Ions move according to molecular dynamics, while excited electrons are treated by a particle-in-cell scheme. We treat the recombination time of electrons as a free parameter in our model. We find that the energy distribution of sputtered ions consists of 2 groups: a low-energy group centered at <1 eV, and a high-energy group at 7–8 eV. Fast ions (mainly Li{sup +}) are emitted early; these charge the surface negatively. Later, larger cluster ions and also neutral LiF molecules are emitted. Emission occurs at low angles to the surface normal. A jet along the normal direction can be observed, which is due to the electric field building up at the track surface. With increasing recombination time, processes are colder; sputtering decreases and the non-thermal jet structure becomes stronger.

  13. Matted-fiber divertor tagets for sputter resistance

    International Nuclear Information System (INIS)

    Gierszewski, P.J.; Todreas, N.E.; Mikic, B.; Yang, T.F.

    1981-06-01

    Reductions in net sputtering yields can be obtained by altering the surface topography to maximize redeposition of sputtered atoms. A simple analysis is used to indicate a potential reduction by a factor of 2 to 5 for matted fiber divertor targets, relatively independent of incident, reflected and sputtered atom distributions. The fiber temperature is also shown to be acceptable, even up to 10 MW/m 2 , for reasonably combinations of materials, fiber diameter and fiber spacing

  14. Weighted Clustering

    DEFF Research Database (Denmark)

    Ackerman, Margareta; Ben-David, Shai; Branzei, Simina

    2012-01-01

    We investigate a natural generalization of the classical clustering problem, considering clustering tasks in which different instances may have different weights.We conduct the first extensive theoretical analysis on the influence of weighted data on standard clustering algorithms in both...... the partitional and hierarchical settings, characterizing the conditions under which algorithms react to weights. Extending a recent framework for clustering algorithm selection, we propose intuitive properties that would allow users to choose between clustering algorithms in the weighted setting and classify...

  15. Sputtering materials for VLSI and thin film devices

    CERN Document Server

    Sarkar, Jaydeep

    2010-01-01

    An important resource for students, engineers and researchers working in the area of thin film deposition using physical vapor deposition (e.g. sputtering) for semiconductor, liquid crystal displays, high density recording media and photovoltaic device (e.g. thin film solar cell) manufacturing. This book also reviews microelectronics industry topics such as history of inventions and technology trends, recent developments in sputtering technologies, manufacturing steps that require sputtering of thin films, the properties of thin films and the role of sputtering target performance on overall p

  16. Computer simulation of the self-sputtering of uranium

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1983-01-01

    The sputtering of polycrystalline α-uranium by uranium ions of energies below 10 keV has been studied in the binary collision approximation using the computer simulation program marlowe. Satisfactory agreement of the computed sputtering yields with the small amount of available experimental data was achieved using the Moliere interatomic potential, a semilocal inelastic loss function, and a planar surface binding barrier, all with conventional parameters. The model is used to discuss low energy sputtering processes and the energy and angular distributions of the reflected primaries and the sputtered target particles

  17. Data compilation of angular distributions of sputtered atoms

    International Nuclear Information System (INIS)

    Yamamura, Yasunori; Takiguchi, Takashi; Tawara, Hiro.

    1990-01-01

    Sputtering on a surface is generally caused by the collision cascade developed near the surface. The process is in principle the same as that causing radiation damage in the bulk of solids. Sputtering has long been regarded as an undesirable dirty effect which destroys the cathodes and grids in gas discharge tubes or ion sources and contaminates plasma and the surrounding walls. However, sputtering is used today for many applications such as sputter ion sources, mass spectrometers and the deposition of thin films. Plasma contamination and the surface erosion of first walls due to sputtering are still the major problems in fusion research. The angular distribution of the particles sputtered from solid surfaces can possibly provide the detailed information on the collision cascade in the interior of targets. This report presents a compilation of the angular distribution of sputtered atoms at normal incidence and oblique incidence in the various combinations of incident ions and target atoms. The angular distribution of sputtered atoms from monatomic solids at normal incidence and oblique incidence, and the compilation of the data on the angular distribution of sputtered atoms are reported. (K.I.)

  18. Cluster management.

    Science.gov (United States)

    Katz, R

    1992-11-01

    Cluster management is a management model that fosters decentralization of management, develops leadership potential of staff, and creates ownership of unit-based goals. Unlike shared governance models, there is no formal structure created by committees and it is less threatening for managers. There are two parts to the cluster management model. One is the formation of cluster groups, consisting of all staff and facilitated by a cluster leader. The cluster groups function for communication and problem-solving. The second part of the cluster management model is the creation of task forces. These task forces are designed to work on short-term goals, usually in response to solving one of the unit's goals. Sometimes the task forces are used for quality improvement or system problems. Clusters are groups of not more than five or six staff members, facilitated by a cluster leader. A cluster is made up of individuals who work the same shift. For example, people with job titles who work days would be in a cluster. There would be registered nurses, licensed practical nurses, nursing assistants, and unit clerks in the cluster. The cluster leader is chosen by the manager based on certain criteria and is trained for this specialized role. The concept of cluster management, criteria for choosing leaders, training for leaders, using cluster groups to solve quality improvement issues, and the learning process necessary for manager support are described.

  19. Beam limiter for thermonuclear fusion devices

    International Nuclear Information System (INIS)

    Kaminsky, M.S.

    1976-01-01

    A beam limiter circumscribes the interior surface of a vacuum vessel to inhibit collisions of contained plasma and the vessel walls. The cross section of the material making up the limiter has a flatsided or slightly concave portion of increased width towards the plasma and portions of decreased width towards the interior surface of the vessel. This configuration is designed to prevent a major fraction of the material sputtered, vaporized and blistered from the limiter from reaching the plasma. It also allows adequate heat transfer from the wider to the narrower portions. The preferred materials for the beam limiter are solids of sintered, particulate materials of low atomic number with low vapor pressure and low sputtering and blistering yields. 7 claims, 3 figures

  20. Sensitivity of ion-induced sputtering to the radial distribution of energy transfers: A molecular dynamics study

    International Nuclear Information System (INIS)

    Mookerjee, S.; Khan, S. A.; Roy, A.; Beuve, M.; Toulemonde, M.

    2008-01-01

    Using different models for the deposition of energy on the lattice and a classical molecular dynamics approach to the subsequent transport, we evaluate how the details of the energy deposition model influence sputtering yield from a Lennard-Jones target irradiated with a MeV/u ion beam. Two energy deposition models are considered: a uniform, instantaneous deposition into a cylinder of fixed radius around the projectile ion track, used in earlier molecular dynamics and fluid dynamics simulations of sputtering yields; and an energy deposition distributed in time and space based on the formalism developed in the thermal spike model. The dependence of the sputtering yield on the total energy deposited on the target atoms is very sensitive to the energy deposition model. To clarify the origin of this strong dependence, we explore the role of the radial expansion of the electronic system prior to the transfer of its energy to the lattice. The results imply that observables such as the sputtering yield may be used as signatures of the fast electron-lattice energy transfer in the electronic energy-loss regime, and indicate the need for more experimental and theoretical investigations of these processes

  1. Developments in broad-beam, ion-source technology and applications

    International Nuclear Information System (INIS)

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

    1982-01-01

    Recent advances in broad-beam, ion-source technology are summarized, including low-energy ion optics, improved extraction grid fabrication, a compact ion-source design and a gridless ion-source design. Recent applications have emphasized concepts such as stress modification of vapor deposited films, very low energy ion beams to minimize the physical sputtering portion in reactive etching, and the use of multiple sources and targets to sputter deposit alloys and compounds. A comprehensive critical review by the same authors appears concurrently, describing in detail the developments in broad-beam, ion-source technology 1 and the applications of these sources. 2

  2. Deposition and characterization of sputtered hexaboride coatings

    International Nuclear Information System (INIS)

    Waldhauser, W.

    1996-06-01

    Hexaborides of the rare-earth elements ReB 6 are potential materials for cathode applications since they combine properties such as low work function, good electrical conductivity, high melting point as well as low volatility at high temperatures. Due to their high hardness and colorations ranging from blue to purple these compounds are also considered for applications to coatings for decoration of consumer products. At present, either rods of sintered LaB 6 or single LaB 6 crystals are indirectly heated to induce emission. In this workboride coatings were deposited onto various substrates employing non-reactive magnetron sputtering from LaB 6 , CeB 6 , SmB 6 and YB 6 targets. Coatings deposited were examined using scanning electron microscopy, X-ray diffraction, electron probe microanalysis. Vickers microhardness, colorimeter and spectroscopic ellipsometry measurements. Electron emission characteristics of the coatings were studied by the thermionic emission and the contact potential method. After optimization of the sputtering parameters fine-columnar or partially amorphous films with atomic ratios of boron to metal in the order of 5 to 7.5 were obtained. The tendency to form the corresponding hexaboride phase decreases from LaB 6 , CeB 6 and SmB 6 to YB 6 . The work function was measured to be in the range of 2.6 to 3.3 eV. Vickers microhardness values lie between 1500 and 2000 HVO.01. LaB 6 coatings showed the most pronounced visual color impression corresponding to dark violet. The results obtained indicate that sputtered hexaboride films are well suited for decorative and thermionic applications. (author)

  3. Forschungszentrum Rossendorf, Institute of Ion Beam Physics and Materials Research. Annual report 2004

    International Nuclear Information System (INIS)

    Borany, J. von; Heera, V.; Helm, M.; Jaeger, H.U.; Moeller, W.

    2005-01-01

    The following topics are dealt with: Silicon based electrically driven microcavity LED, ultraviolet electroluminescence from a Gd-implanted Si-metal-oxide-semiconductor device, semiconductor quantum-cascade lasers, ion beam synthesis and morphology of semiconductor memories, ion implantation, films, sputtering, ion-beam induced destabilization of nanoparticles. (HSI)

  4. Forschungszentrum Rossendorf, Institute of Ion Beam Physics and Materials Research. Annual report 2004

    Energy Technology Data Exchange (ETDEWEB)

    Borany, J. von; Heera, V.; Helm, M.; Jaeger, H.U.; Moeller, W. (eds.)

    2005-07-01

    The following topics are dealt with: Silicon based electrically driven microcavity LED, ultraviolet electroluminescence from a Gd-implanted Si-metal-oxide-semiconductor device, semiconductor quantum-cascade lasers, ion beam synthesis and morphology of semiconductor memories, ion implantation, films, sputtering, ion-beam induced destabilization of nanoparticles. (HSI)

  5. Reactive sputter deposition of boron nitride

    International Nuclear Information System (INIS)

    Jankowski, A.F.; Hayes, J.P.; McKernan, M.A.; Makowiecki, D.M.

    1995-10-01

    The preparation of fully dense, boron targets for use in planar magnetron sources has lead to the synthesis of Boron Nitride (BN) films by reactive rf sputtering. The deposition parameters of gas pressure, flow and composition are varied along with substrate temperature and applied bias. The films are characterized for composition using Auger electron spectroscopy, for chemical bonding using Raman spectroscopy and for crystalline structure using transmission electron microscopy. The deposition conditions are established which lead to the growth of crystalline BN phases. In particular, the growth of an adherent cubic BN coating requires 400--500 C substrate heating and an applied -300 V dc bias

  6. Development of the sputter coater for hotcell

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Yong Bum; Kwon, H. M.; Chun, Y. B.; Yang, Y. S.; Joo, J. S.; Jang, N. M

    2007-05-15

    In last december, the Wavelength Dispersive Spectroscopy (WDS) was installed on the shielded SEM of PIEF, KAERI. Before the first major WDS analysis service at the end of 2007, one among the prior technologies, the hot-cell sputter coater was remodelled from a commercial product and set up inside the glove box. This report describes effects of a coating layer on quantitative analysis, the remodelling of a coater suited to hot-cell, and the performance test of the remodelled coater. Also, written in 1998 was revised and appended to the report.

  7. Thermal conductivity of sputtered amorphous Ge films

    International Nuclear Information System (INIS)

    Zhan, Tianzhuo; Xu, Yibin; Goto, Masahiro; Tanaka, Yoshihisa; Kato, Ryozo; Sasaki, Michiko; Kagawa, Yutaka

    2014-01-01

    We measured the thermal conductivity of amorphous Ge films prepared by magnetron sputtering. The thermal conductivity was significantly higher than the value predicted by the minimum thermal conductivity model and increased with deposition temperature. We found that variations in sound velocity and Ge film density were not the main factors in the high thermal conductivity. Fast Fourier transform patterns of transmission electron micrographs revealed that short-range order in the Ge films was responsible for their high thermal conductivity. The results provide experimental evidences to understand the underlying nature of the variation of phonon mean free path in amorphous solids

  8. Isotopic clusters

    International Nuclear Information System (INIS)

    Geraedts, J.M.P.

    1983-01-01

    Spectra of isotopically mixed clusters (dimers of SF 6 ) are calculated as well as transition frequencies. The result leads to speculations about the suitability of the laser-cluster fragmentation process for isotope separation. (Auth.)

  9. Cluster Headache

    Science.gov (United States)

    ... a role. Unlike migraine and tension headache, cluster headache generally isn't associated with triggers, such as foods, hormonal changes or stress. Once a cluster period begins, however, drinking alcohol ...

  10. The influence of beam divergence on ion-beam induced surface patterns

    International Nuclear Information System (INIS)

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

    2009-01-01

    We present a continuum theory and a Monte Carlo model of self-organized surface pattern formation by ion-beam sputtering including effects of beam profiles. Recently, it has turned out that such secondary ion-beam parameters may have a strong influence on the types of emerging patterns. We first discuss several cases, for which beam profiles lead to random parameters in the theory of pattern formation. Subsequently we study the evolution of the averaged height profile in continuum theory and find that the typical Bradley-Harper scenario of dependence of ripple patterns on the angle of incidence can be changed qualitatively. Beam profiles are implemented in Monte Carlo simulations, where we find generic effects on pattern formation. Finally, we demonstrate that realistic beam profiles, taken from experiments, may lead to qualitative changes of surface patterns.

  11. Ion source with radiofrequency mass filter for sputtering purposes

    International Nuclear Information System (INIS)

    Sielanko, J.; Sowa, M.

    1990-01-01

    The Kaufman ion source with radiofrequency mass filter is described. The construction as well as operating characteristics of ion source are presented. The arrangement is suitable for range distribution measurements of implanted layers, where the sputtering rate has to be constant over the wide range of sputtering time. 4 figs., 17 refs. (author)

  12. Low-dose effects in the sputtering of evaporated films

    International Nuclear Information System (INIS)

    Florio, A.R.O.; Alonso, E.V.; Baragiola, R.A.; Ferron, J.

    1983-01-01

    We report measurements of the dose dependence of the sputtering of evaporated films by 30 keV ions under UHV. An initial (sub-monolayer) enhanced sputtering is attributed to the removal of weakly bound atoms; this enhancement does not depend on the incidence angle of the projectile. (author)

  13. Low-dose effects in the sputtering of evaporated films

    Energy Technology Data Exchange (ETDEWEB)

    Florio, A.R.O.; Alonso, E.V.; Baragiola, R.A.; Ferron, J. (Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche)

    1983-05-01

    We report measurements of the dose dependence of the sputtering of evaporated films by 30 keV ions under UHV. An initial (sub-monolayer) enhanced sputtering is attributed to the removal of weakly bound atoms; this enhancement does not depend on the incidence angle of the projectile.

  14. Sputtering of Ge(001): transition between dynamic scaling regimes

    DEFF Research Database (Denmark)

    Smilgies, D.-M.; Eng, P.J.; Landemark, E.

    1997-01-01

    We have studied the dynamic behavior of the Ge(001) surface during sputtering in situ and in real time using synchrotron X-ray diffraction. We find two dynamic regimes as a function of surface temperature and sputter current which are separated by a sharp transition. The boundary between these two...

  15. Sputtering of Thick Deuterium Films by KeV Electrons

    DEFF Research Database (Denmark)

    Thestrup Nielsen, Birgitte; Svendsen, Winnie Edith; Schou, Jørgen

    1994-01-01

    Sputtering of thick films of solid deuterium up to several μm by keV electrons is reported for the first time. The sputtering yield increases within a narrow range of thicknesses around 1.6 μm by about 2 orders of magnitude for 1.5 keV electrons. A similar behavior has not been observed for ion...

  16. RF sputtering: A viable tool for MEMS fabrication

    Indian Academy of Sciences (India)

    being prepared by RF sputtering and their application in MEMS being explored. ... crystallographic properties were evaluated using XRD analysis (CuKα radiation ..... Bhatt V, Pal P, Chandra S 2005 Feasibility study of RF sputtered ZnO film for ...

  17. Sputtering of solid nitrogen by keV helium ions

    DEFF Research Database (Denmark)

    Ellegaard, O.; Schou, Jørgen; Sørensen, H.

    1993-01-01

    Solid nitrogen has become a standard material among the frozen molecular gases for electronic sputtering. We have combined measurements of sputtering yields and energy spectra from nitrogen bombarded by 4-10 keV helium ions. The data show that the erosion is electronic rather than knockon...

  18. Cluster Headache

    OpenAIRE

    Pearce, Iris

    1985-01-01

    Cluster headache is the most severe primary headache with recurrent pain attacks described as worse than giving birth. The aim of this paper was to make an overview of current knowledge on cluster headache with a focus on pathophysiology and treatment. This paper presents hypotheses of cluster headache pathophysiology, current treatment options and possible future therapy approaches. For years, the hypothalamus was regarded as the key structure in cluster headache, but is now thought to be pa...

  19. Categorias Cluster

    OpenAIRE

    Queiroz, Dayane Andrade

    2015-01-01

    Neste trabalho apresentamos as categorias cluster, que foram introduzidas por Aslak Bakke Buan, Robert Marsh, Markus Reineke, Idun Reiten e Gordana Todorov, com o objetivo de categoriíicar as algebras cluster criadas em 2002 por Sergey Fomin e Andrei Zelevinsky. Os autores acima, em [4], mostraram que existe uma estreita relação entre algebras cluster e categorias cluster para quivers cujo grafo subjacente é um diagrama de Dynkin. Para isto desenvolveram uma teoria tilting na estrutura triang...

  20. Irradiation characteristics of metal-cluster-complex ions containing diverse multi-elements with large mass differences

    International Nuclear Information System (INIS)

    Fujiwara, Yukio; Kondou, Kouji; Teranishi, Yoshikazu; Nonaka, Hidehiko; Saito, Naoaki; Fujimoto, Toshiyuki; Kurokawa, Akira; Ichimura, Shingo; Tomita, Mitsuhiro

    2007-01-01

    Tetrairidium dodecacarbonyl, Ir 4 (CO) 12 , is a metal cluster complex which has a molecular weight of 1104.9. Using a metal-cluster-complex ion source, the interaction between Ir 4 (CO) n + ions (n=0-12) and silicon substrates was studied at a beam energy ranging from 2keV to 10keV at normal incidence. By adjusting Wien-filter voltage, the influence of CO ligands was investigated. Experimental results showed that sputtering yield of silicon bombarded with Ir 4 (CO) n + ions at 10keV decreased with the number of CO ligands. In the case of 2keV, deposition tended to be suppressed by removing CO ligands from the impinging cluster ions. The influence of CO ligands was explained by considering changes in surface properties caused by the irradiation of Ir 4 (CO) n + ions. It was also found that the bombardment with Ir 4 (CO) 7 + ions at 2.5keV caused deposition on silicon target

  1. Meaningful Clusters

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Calapristi, Augustin J.; Crow, Vernon L.; Hetzler, Elizabeth G.; Turner, Alan E.

    2004-05-26

    We present an approach to the disambiguation of cluster labels that capitalizes on the notion of semantic similarity to assign WordNet senses to cluster labels. The approach provides interesting insights on how document clustering can provide the basis for developing a novel approach to word sense disambiguation.

  2. Horticultural cluster

    OpenAIRE

    SHERSTIUK S.V.; POSYLAYEVA K.I.

    2013-01-01

    In the article there are the theoretical and methodological approaches to the nature and existence of the cluster. The cluster differences from other kinds of cooperative and integration associations. Was develop by scientific-practical recommendations for forming a competitive horticultur cluster.

  3. 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.)

  4. Modelling of low energy ion sputtering from oxide surfaces

    International Nuclear Information System (INIS)

    Kubart, T; Nyberg, T; Berg, S

    2010-01-01

    The main aim of this work is to present a way to estimate the values of surface binding energy for oxides. This is done by fitting results from the binary collisions approximation code Tridyn with data from the reactive sputtering processing curves, as well as the elemental composition obtained from x-ray photoelectron spectroscopy (XPS). Oxide targets of Al, Ti, V, Nb and Ta are studied. The obtained surface binding energies are then used to predict the partial sputtering yields. Anomalously high sputtering yield is observed for the TiO 2 target. This is attributed to the high sputtering yield of Ti lower oxides. Such an effect is not observed for the other studied metals. XPS measurement of the oxide targets confirms the formation of suboxides during ion bombardment as well as an oxygen deficient surface in the steady state. These effects are confirmed from the processing curves from the oxide targets showing an elevated sputtering rate in pure argon.

  5. Supersonic copper clusters

    International Nuclear Information System (INIS)

    Powers, D.E.; Hansen, S.G.; Geusic, M.E.; Michalopoulos, D.L.; Smalley, R.E.

    1983-01-01

    Copper clusters ranging in size from 1 to 29 atoms have been prepared in a supersonic beam by laser vaporization of a rotating copper target rod within the throat of a pulsed supersonic nozzle using helium for the carrier gas. The clusters were cooled extensively in the supersonic expansion [T(translational) 1 to 4 K, T(rotational) = 4 K, T(vibrational) = 20 to 70 K]. These clusters were detected in the supersonic beam by laser photoionization with time-of-flight mass analysis. Using a number of fixed frequency outputs of an exciplex laser, the threshold behavior of the photoionization cross section was monitored as a function of cluster size.nce two-photon ionization (R2PI) with mass selective detection allowed the detection of five new electronic band systems in the region between 2690 and 3200 A, for each of the three naturally occurring isotopic forms of Cu 2 . In the process of scanning the R2PI spectrum of these new electronic states, the ionization potential of the copper dimer was determined to be 7.894 +- 0.015 eV

  6. Characteristics of W Doped Nanocrystalline Carbon Films Prepared by Unbalanced Magnetron Sputtering.

    Science.gov (United States)

    Park, Yong Seob; Park, Chul Min; Kim, Nam-Hoon; Kim, Jae-Moon

    2016-05-01

    Nanocrystalline tungsten doped carbon (WC) films were prepared by unbalanced magnetron sputtering. Tungsten was used as the doping material in carbon thin films with the aim of application as a contact strip in an electric railway. The structural, physical, and electrical properties of the fabricated WC films with various DC bias voltages were investigated. The films had a uniform and smooth surface. Hardness and frication characteristics of the films were improved, and the resistivity and sheet resistance decreased with increasing negative DC bias voltage. These results are associated with the nanocrystalline WC phase and sp(2) clusters in carbon networks increased by ion bombardment enhanced with increasing DC bias voltage. Consequently, the increase of sp(2) clusters containing WC nanocrystalline in the carbon films is attributed to the improvement in the physical and electrical properties.

  7. Comparison of Se and Te clusters produced by ion bombardment

    Directory of Open Access Journals (Sweden)

    Trzyna Małgorzata

    2017-01-01

    Full Text Available Nanostructures based on tellurium and selenium are materials used as components for the manufacturing topological insulators. Therefore it is crucial to precisely characterize these materials. In this work the emission of selenium and tellurium cluster ions, sputtered by Bi+ primary ion guns, was investigated by using Time-of-Flight Secondary Ion Mass Spectrometry (TOF SIMS. It has been found that BixTex and BixSex clusters appear in addition to Sex and Tex clusters in the mass range up to ~ 1300 m/z. Local maxima or minima (magic numbers are observed in the ion intensity versus a number of atoms per cluster for both positive and negative ions spectra for all types of clusters and primary ions used. These extrema can be attributed to different yield and stability of certain clusters but also to fragmentation of high-mass clusters.

  8. Comparison of Se and Te clusters produced by ion bombardment

    Science.gov (United States)

    Trzyna, Małgorzata

    2017-01-01

    Nanostructures based on tellurium and selenium are materials used as components for the manufacturing topological insulators. Therefore it is crucial to precisely characterize these materials. In this work the emission of selenium and tellurium cluster ions, sputtered by Bi+ primary ion guns, was investigated by using Time-of-Flight Secondary Ion Mass Spectrometry (TOF SIMS). It has been found that BixTex and BixSex clusters appear in addition to Sex and Tex clusters in the mass range up to 1300 m/z. Local maxima or minima (magic numbers) are observed in the ion intensity versus a number of atoms per cluster for both positive and negative ions spectra for all types of clusters and primary ions used. These extrema can be attributed to different yield and stability of certain clusters but also to fragmentation of high-mass clusters.

  9. Thermal conductivities of thin, sputtered optical films

    International Nuclear Information System (INIS)

    Henager, C.H. Jr.; Pawlewicz, W.T.

    1991-05-01

    The normal component of the thin film thermal conductivity has been measured for the first time for several advanced sputtered optical materials. Included are data for single layers of boron nitride (BN), aluminum nitride (AIN), silicon aluminum nitride (Si-Al-N), silicon aluminum oxynitride (Si-Al-O-N), silicon carbide (SiC), and for dielectric-enhanced metal reflectors of the form Al(SiO 2 /Si 3 N 4 ) n and Al(Al 2 O 3 /AIN) n . Sputtered films of more conventional materials like SiO 2 , Al 2 O 3 , Ta 2 O 5 , Ti, and Si have also been measured. The data show that thin film thermal conductivities are typically 10 to 100 times lower than conductivities for the same materials in bulk form. Structural disorder in the amorphous or very fine-grained films appears to account for most of the conductivity difference. Conclusive evidence for a film/substrate interface contribution is presented

  10. Evolution of film temperature during magnetron sputtering

    International Nuclear Information System (INIS)

    Shaginyan, L.R.; Han, J.G.; Shaginyan, V.R.; Musil, J.

    2006-01-01

    We report on the results of measurements of the temperature T F surf which developed on the surface of films deposited by magnetron sputtering of chromium and copper targets on cooling and non-cooling silicon substrates. The T F surf and substrate temperature (T s ) were simultaneously measured using high-resolution IR camera and thermocouple, respectively. We revealed that the T F surf steeply grows, keeps constant when it achieves saturation level, and rapidly drops to the value of the T s after stopping the deposition. At the same time, the T s either does not change for the case of cooling substrate or increases to a certain level for noncooling substrate. However, in both cases the T s remains several times lower than the T F surf . The T F surf is proportional to the flux of energy delivered to the growth surface by sputtered atoms and other fast particles, weakly depends on the depositing metal and can achieve several hundreds of deg. C. This phenomenon is explained by a model assuming formation of a hot thin surface layer (HTSL) on the top of the growing film, which exists only during film deposition and exhibits extremely low thermal conductivity. Due to this unique property the temperature T F surf of HTSL is several times higher than the T s . Variations in the T F surf fairly correlate with structure changes of Cr films along thickness investigated in detail previously

  11. Giant Negative Piezoresistive Effect in Diamond-like Carbon and Diamond-like Carbon-Based Nickel Nanocomposite Films Deposited by Reactive Magnetron Sputtering of Ni Target

    DEFF Research Database (Denmark)

    Meškinis, Šaru Nas; Gudaitis, Rimantas; Šlapikas, Kęstutis

    2018-01-01

    deposited by either reactive HIPIMS or dc magnetron sputtering of Ni target was explained by possible clustering of the sp2-bonded carbon and/or formation of areas with the decreased hydrogen content. It was suggested that the tensile stress-induced rearrangements of these conglomerations have resulted......Piezoresistive properties of hydrogenated diamond-like carbon (DLC) and DLC-based nickel nanocomposite (DLC:Ni) films were studied in the range of low concentration of nickel nanoparticles. The films were deposited by reactive high power pulsed magnetron sputtering (HIPIMS) of Ni target, and some...... samples were deposited by direct current (dc) reactive magnetron sputtering for comparison purposes. Raman scattering spectroscopy, energy-dispersive X-ray spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS) were used to study the structure and chemical composition of the films. A four...

  12. Experimental and analytical study of the sputtering phenomena

    International Nuclear Information System (INIS)

    Howard, P.A.

    1976-03-01

    One form of the sputtering phenomena, the heat-transfer process that occurs when an initially hot vertical surface is cooled by a falling liquid film, was examined from a new experimental approach. The sputtering front is the lowest wetted position on the vertical surface and is characterized by a short region of intense nucleate boiling. The sputtering front progresses downward at nearly a constant rate, the surface below the sputtering front being dry and almost adiabatic. This heat-transfer process is of interest in the analysis of some of the performance aspects of emergency core-cooling systems of light-water reactors. An experimental apparatus was constructed to examine the heat-transfer characteristics of a sputtering front. In the present study, a heat source of sufficient intensity was located immediately below the sputtering front, which prevented its downward progress, thus permitting detailed measurements of steady-state surface temperatures throughout a sputtering front. Experimental evidence showed the sputtering front to correspond to a critical heat-flux (CHF) phenomenon. Data were obtained with water flow rates of 350-1600 lb/sub m//hr-ft and subcoolings of 40-140 0 F on a 3 / 8 -in. solid copper rod at 1 atm. A two-dimensional analytical model was developed to describe a stationary sputtering front where the wet-dry interface corresponds to a CHF phenomena and the dry zone is adiabatic. This model is nonlinear because of the temperature dependence of the heat-transfer coefficient in the wetted region and has yielded good agreement with data. A simplified one-dimensional approximation was developed which adequately describes these data. Finally, by means of a coordinate transformation and additional simplifying assumptions, this analysis was extended to analyze moving sputtering fronts, and reasonably good agreement with reported data was shown

  13. Sputtering effect of low-energy ions on biological target: The analysis of sputtering product of urea and capsaicin

    International Nuclear Information System (INIS)

    Zhang, Lili; Xu, Xue; Wu, Yuejin

    2013-01-01

    Sputtering is a process whereby atoms are ejected from a solid target material due to bombardment of the target by energetic particles. Recent years, ion implantation was successfully applied to biological research based on the fragments sputtering and form open paths in cell structure caused by ion sputtering. In this study, we focused on urea and chilli pepper pericarp samples implanted with N + and Ar + ions. To investigate the sputtering effect, we designed a collecting unit containing a disk sample and a glass pipe. The urea content and capsaicin content recovered from glass pipes were adopted to represent the sputtering product. The result of urea showed that the sputtering effect is positively correlated with the ion energy and dose, also affected by the ion type. The result of capsaicin was different from that of urea at 20 keV and possibly due to biological complex composition and structure. Therefore the sputtering yield depended on both the parameters of incident ions and the state of target materials. The sputtering yield of urea was also simulated by computational method achieved through the TRIM program. The trajectories of primary and recoiled atoms were calculated on the basis of the binary collision approximation using Monte Carlo method. The experimental results were much higher than the calculated results. The possible explanation is that in the physical model the target were assumed as a disordered lattice and independent atoms, which is much less complicated than that of the biological models

  14. On a relationship between the geometry of cones on sputtered surfaces and the angular dependence of sputtered yields

    International Nuclear Information System (INIS)

    Chadderton, L.T.

    1977-01-01

    It is widely believed that the phenomenon responsible for the familiar peak in the angular dependence of sputtered yields also gives rise to characteristic semiangles α of conical protruberances on sputtered surfaces. It is shown that α corresponds to the process giving rise to the minimum rather than the maximum. No accurate measurements of the minimum have yet been made. (Auth.)

  15. Cluster Matters

    DEFF Research Database (Denmark)

    Gulati, Mukesh; Lund-Thomsen, Peter; Suresh, Sangeetha

    2018-01-01

    sell their products successfully in international markets, but there is also an increasingly large consumer base within India. Indeed, Indian industrial clusters have contributed to a substantial part of this growth process, and there are several hundred registered clusters within the country...... of this handbook, which focuses on the role of CSR in MSMEs. Hence we contribute to the literature on CSR in industrial clusters and specifically CSR in Indian industrial clusters by investigating the drivers of CSR in India’s industrial clusters....

  16. A high-intensity plasma-sputter heavy negative ion source

    International Nuclear Information System (INIS)

    Alton, G.D.; Mori, Y.; Takagi, A.; Ueno, A.; Fukumoto, S.

    1989-01-01

    A multicusp magnetic field plasma surface ion source, normally used for H/sup /minus//ion beam formation, has been modified for the generation of high-intensity, pulsed, heavy negative ion beams suitable for a variety of uses. To date, the source has been utilized to produce mA intensity pulsed beams of more than 24 species. A brief description of the source, and basic pulsed-mode operational data, (e.g., intensity versus cesium oven temperature, sputter probe voltage, and discharge pressure), are given. In addition, illustrative examples of intensity versus time and the mass distributions of ion beams extracted from a number of samples along with emittance data, are also presented. Preliminary results obtained during dc operation of the source under low discharge power conditions suggest that sources of this type may also be used to produce high-intensity (mA) dc beams. The results of these investigations are given, as well, and the technical issues that must be addressed for this mode of operation are discussed. 15 refs., 10 figs., 2 tabs

  17. Implantation of keV-energy argon clusters and radiation damage in diamond

    DEFF Research Database (Denmark)

    Popok, Vladimir; Samela, Juha; Nordlund, Kai

    2012-01-01

    We show that for impacting argon clusters, both mean projected ranges of the constituents and depths of radiation damage in diamond scale linearly with momentum. The same dependence was earlier found for keV-energy cluster implantation in graphite, thus suggesting the universality of this scaling...... law. For diamond, a good agreement for the value of displacement energy for the case of cluster impact is found by comparing the calculated target sputtering and experimentally measured depth of radiation damage....

  18. 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

  19. Sputtering yields and surface chemical modification of tin-doped indium oxide in hydrocarbon-based plasma etching

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hu; Karahashi, Kazuhiro; Hamaguchi, Satoshi, E-mail: hamaguch@ppl.eng.osaka-u.ac.jp [Center for Atomic and Molecular Technologies, Osaka University, Yamadaoka 2-1, Suita 565-0871 (Japan); Fukasawa, Masanaga; Nagahata, Kazunori; Tatsumi, Tetsuya [Device and Material R& D Group, RDS Platform, Sony Corporation, Kanagawa 243-0014 (Japan)

    2015-11-15

    Sputtering yields and surface chemical compositions of tin-doped indium oxide (or indium tin oxide, ITO) by CH{sup +}, CH{sub 3}{sup +}, and inert-gas ion (He{sup +}, Ne{sup +}, and Ar{sup +}) incidence have been obtained experimentally with the use of a mass-selected ion beam system and in-situ x-ray photoelectron spectroscopy. It has been found that etching of ITO is chemically enhanced by energetic incidence of hydrocarbon (CH{sub x}{sup +}) ions. At high incident energy incidence, it appears that carbon of incident ions predominantly reduce indium (In) of ITO and the ITO sputtering yields by CH{sup +} and CH{sub 3}{sup +} ions are found to be essentially equal. At lower incident energy (less than 500 eV or so), however, a hydrogen effect on ITO reduction is more pronounced and the ITO surface is more reduced by CH{sub 3}{sup +} ions than CH{sup +} ions. Although the surface is covered more with metallic In by low-energy incident CH{sub 3}{sup +} ions than CH{sup +} ions and metallic In is in general less resistant against physical sputtering than its oxide, the ITO sputtering yield by incident CH{sub 3}{sup +} ions is found to be lower than that by incident CH{sup +} ions in this energy range. A postulation to account for the relation between the observed sputtering yield and reduction of the ITO surface is also presented. The results presented here offer a better understanding of elementary surface reactions observed in reactive ion etching processes of ITO by hydrocarbon plasmas.

  20. Coherent beam-beam effects

    International Nuclear Information System (INIS)

    Chao, A.W.

    1992-01-01

    There are two physical pictures that describe the beam-beam interaction in a storage ring collider: The weak-strong and the strong-strong pictures. Both pictures play a role in determining the beam-beam behavior. This review addresses only the strong-strong picture. The corresponding beam dynamical effects are referred to as the coherent beam-beam effects. Some basic knowledge of the weak-strong picture is assumed. To be specific, two beams of opposite charges are considered. (orig.)