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Sample records for assisted deposition ibad

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

    Institute of Scientific and Technical Information of China (English)

    F. Pan; F. Zeng; B. Zhao

    2002-01-01

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

  2. Reel-to-reel preparation of ion-beam assisted deposition (IBAD)-MgO based coated conductors

    International Nuclear Information System (INIS)

    We report on our efforts in developing and scaling-up the systems for IBAD-MgO based coated conductor fabrication. The overall fabrication process involves a number of different processes including: electropolishing of the substrates; barrier-layer, seed-layer, and IBAD-MgO deposition by e-beam evaporation; and pulsed laser deposition of buffer and YBCO layers. All processes are realized in reel-to-reel processing systems. Latest results have shown that the IBAD-MgO approach yields coated conductor performance comparable to the best results achieved elsewhere to date

  3. Reel-to-reel preparation of ion-beam assisted deposition (IBAD)-MgO based coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Kreiskott, Sascha; Arendt, Paul N; Coulter, J Yates; Dowden, Paul C; Foltyn, Stephen R; Gibbons, Brady J; Matias, Vladimir; Sheehan, Chris J [Superconductivity Technology Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2004-05-01

    We report on our efforts in developing and scaling-up the systems for IBAD-MgO based coated conductor fabrication. The overall fabrication process involves a number of different processes including: electropolishing of the substrates; barrier-layer, seed-layer, and IBAD-MgO deposition by e-beam evaporation; and pulsed laser deposition of buffer and YBCO layers. All processes are realized in reel-to-reel processing systems. Latest results have shown that the IBAD-MgO approach yields coated conductor performance comparable to the best results achieved elsewhere to date.

  4. Pulsed laser deposition of YBCO thin films on IBAD-YSZ substrates

    International Nuclear Information System (INIS)

    High-quality YBa2Cu3O7-x (YBCO) films were fabricated on yttria-stabilized zirconia (YSZ)-buffered Hastelloy C276 substrates by pulsed laser deposition. YSZ was grown by ion-beam-assisted deposition. A thin (∼10 nm) CeO2 layer was deposited before the deposition of YBCO. The crystalline structure and biaxial texture of the YBCO film and the buffer layer were examined by x-ray diffraction 2θ-scan, φ-scan and pole-figure analysis. Epitaxial growth of the YBCO film on the buffer layer was observed. Full width at half maximum (FWHM) value of 7.4 deg. was measured from the φ-scan of YBCO(103). Raman spectroscopy showed compositional uniformity and phase integrity in the YBCO films. Surface morphologies of the YBCO films were examined by scanning electron microscopy. Comparative studies indicated that the CeO2 buffer layer significantly improves the structural alignment and superconducting properties of YBCO films. Tc = 90 K, with sharp transition, and transport Jc = 2.2 x 106 A cm-2 at 77 K in zero-external field were obtained on the 0.5 μm thick YBCO films. The dependence of Jc on the FWHM of the YBCO(103) φ-scan indicated that high Jc is associated with low FWHM

  5. Creation of biomaterials using the dual beam IBAD methods

    International Nuclear Information System (INIS)

    The Dual Beam Ion Assisted Deposition technique (IBAD) application for creation of the hard, biocompatible coating layers has been presented and discussed. As substrate the stainless steel, Ti, special titanium alloys, the Al2O3 or other solid materials can be used. Presently, the biocompatible coating layers such as DLC (Diamond Like Coating), β-SiC, TiC, hydroxyapatite and thin coating layer based on Ca, P, O, H have been prepared and investigated

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

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    LIUZhong-Yang; WANGChang-Xing; 等

    2002-01-01

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

  8. Tilting of carbon encapsulated metallic nanocolumns in carbon-nickel nanocomposite films by ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Matthias [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Technische Universitaet Dresden, D-01062 Dresden (Germany); Muecklich, Arndt; Zschornak, Matthias; Wintz, Sebastian; Gemming, Sibylle; Abrasonis, Gintautas [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Oates, Thomas W. H. [Leibniz-Institut fuer Analytische Wissenschaft, ISAS e.V., Albert-Einstein-Str. 9, 12489 Berlin (Germany); Luis Endrino, Jose [Surfaces and Coatings Department, Instituto de Ciencia de Materiales de Madrid, c/Sor Juana Ines de la Cruz 3, Cantoblanco, 28049 Madrid (Spain); Baehtz, Carsten; Shalimov, Artem [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Rossendorf Beamline, European Synchrotron Radiation Facility, F-38043 Grenoble (France)

    2012-07-30

    The influence of assisting low-energy ({approx}50-100 eV) ion irradiation effects on the morphology of C:Ni ({approx}15 at. %) nanocomposite films during ion beam assisted deposition (IBAD) is investigated. It is shown that IBAD promotes the columnar growth of carbon encapsulated metallic nanoparticles. The momentum transfer from assisting ions results in tilting of the columns in relation to the growing film surface. Complex secondary structures are obtained, in which a significant part of the columns grows under local epitaxy via the junction of sequentially deposited thin film fractions. The influence of such anisotropic film morphology on the optical properties is highlighted.

  9. Ion-beam assisted deposition of MgO with in situ RHEED monitoring to control Bi-axial texture

    Energy Technology Data Exchange (ETDEWEB)

    Arendt, P. N. (Paul N.); Foltyn, S. R. (Stephen R.); Jia, Quanxi; DePaula, R. F. (Raymond Felix); Dowden, P. C. (Paul C.); Kung, H. (Harriett); Holesinger, T. G. (Terry G.); Stan, L. (Liliana); Emmert, L. A. (Luke A.); Peterson, E. J. (Eric J.); Groves, J. R. (James R.)

    2001-01-01

    We have studied the growth of magnesium oxide using ion-beam assisted deposition (IBAD) to achieve (100) oriented, bi-axially textured films with low mosaic spread, for film thicknesses of 10 nm on silicon substrates. We have refined the process by using reflected high-energy electron diffraction (RHEED) to monitor the growth of IBAD MgO films and found that the diffracted intensity can be used to determine (and ultimately control) final in-plane texture of the film. Here we present results on our work to develop the use of real-time RHEED monitoring to deposit well-oriented IBAD MgO films. The results have been corroborated with extensive grazing-incidence X-ray diffraction (GID). Results of these analyses have allowed us to deposit films on metallic substrates with in-plane mosaic spread less than 7{sup o}.

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

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

    2016-06-01

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

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

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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

  13. YBCO films grown by reactive co-evaporation on simplified IBAD-MgO coated conductor templates

    International Nuclear Information System (INIS)

    We demonstrate coated conductors fabricated by reactive co-evaporation of YBa2Cu3Oy (YBCO) by cyclic deposition and reaction (RCE-CDR) on ion-beam-assisted-deposition- (IBAD-) textured templates simplified by the elimination of the epitaxial buffer layer. Hastelloy substrates, both polished and unpolished, were used as a starting material for the IBAD templates. Y2O3 bed layers were then deposited followed by IBAD-textured MgO and a thin homoepitaxial MgO layer. The MgO-terminated templates were used for direct deposition of YBCO by RCE-CDR. Critical current densities obtained for the undoped YBCO material are comparable to the best values measured previously with the use of LaMnO3 or SrTiO3 epitaxial buffer layers and state-of-the-art coated conductor results. The structural characterization data indicate a well oriented YBCO film with a robust template. Electrical measurements also indicate no weak links and a typical magnetic field behavior of undoped YBCO, characterized by a low density of naturally occurring strong pinning centers and correlations along the ab direction.

  14. Creation of the SiCx layers as interface of hard wear protective coatings by dual beam IBAD method

    International Nuclear Information System (INIS)

    The paper presents the current status of research connected with forming one- and multi-layer, anti wear, microcrystalline and amorphous coatings, one-element (e.g. Diamond Like carbon coatings) (DLC) and multi-element (e. g. SiC) at the application of dual beam IBAD (Ion Beam Assisted Deposition) method. This method features high technological flexibility, consisting in the possibility of composing layers with desired properties with the coating's good adhesion to the substrate. In the research on the formed coatings, the method of detecting backscattered charged particles (RBS - Rutherford Backscattering Spectroscopy) and for specifying tribological features set of mechanical methods were used. (author)

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

    Directory of Open Access Journals (Sweden)

    A. Twardowska

    2009-11-01

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

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

    Science.gov (United States)

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

    2016-07-01

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

  17. Effects of calcium phosphate coating to SLA surface implants by the ion-beam-assisted deposition method on self-contained coronal defect healing in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Heun-Joo; Song, Ji-Eun; Um, Yoo-Jung; Chae, Gyung Joon; Jung, Ui-Won; Kim, Chang-Sung; Choi, Seong-Ho [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Chung, Sung-Min [Dentium Co., Seoul (Korea, Republic of); Lee, In-Seop, E-mail: shchoi726@yuhs.a [Institute of Physics and Applied Physics, Atomic-scale Surface Science Research Center, Yonsei University, Seoul (Korea, Republic of)

    2009-08-15

    The aim of this study was to evaluate the healing of self-contained coronal defects on a sand-blasted, large-grit, acid-etched (SLA) surface implant, which had a calcium phosphate (CaP) coating applied by ion-beam-assisted deposition (IBAD). We also evaluated the effect of heating the coating to different temperatures. The CaP-coated SLA implants exhibited a slightly larger bone healing capacity in the self-contained coronal defect than SLA implants, indicating that combining SLA surface implants and a CaP coating by the IBAD method had synergistic effects on bone healing. There was no difference in the healing capacity between 350 deg. C and 450 deg. C heat treatment of the coating layer.

  18. Effects of calcium phosphate coating to SLA surface implants by the ion-beam-assisted deposition method on self-contained coronal defect healing in dogs.

    Science.gov (United States)

    Yoon, Heun-Joo; Song, Ji-Eun; Um, Yoo-Jung; Chae, Gyung Joon; Chung, Sung-Min; Lee, In-Seop; Jung, Ui-Won; Kim, Chang-Sung; Choi, Seong-Ho

    2009-08-01

    The aim of this study was to evaluate the healing of self-contained coronal defects on a sand-blasted, large-grit, acid-etched (SLA) surface implant, which had a calcium phosphate (CaP) coating applied by ion-beam-assisted deposition (IBAD). We also evaluated the effect of heating the coating to different temperatures. The CaP-coated SLA implants exhibited a slightly larger bone healing capacity in the self-contained coronal defect than SLA implants, indicating that combining SLA surface implants and a CaP coating by the IBAD method had synergistic effects on bone healing. There was no difference in the healing capacity between 350 degrees C and 450 degrees C heat treatment of the coating layer.

  19. Effects of calcium phosphate coating to SLA surface implants by the ion-beam-assisted deposition method on self-contained coronal defect healing in dogs

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the healing of self-contained coronal defects on a sand-blasted, large-grit, acid-etched (SLA) surface implant, which had a calcium phosphate (CaP) coating applied by ion-beam-assisted deposition (IBAD). We also evaluated the effect of heating the coating to different temperatures. The CaP-coated SLA implants exhibited a slightly larger bone healing capacity in the self-contained coronal defect than SLA implants, indicating that combining SLA surface implants and a CaP coating by the IBAD method had synergistic effects on bone healing. There was no difference in the healing capacity between 350 deg. C and 450 deg. C heat treatment of the coating layer.

  20. Development of the IBAD MgO process for HTS coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Groves, J. R. (James R.); Arendt, P. N. (Paul N.); Foltyn, S. R. (Stephen R.); Jia, Quanxi; Holesinger, T. G. (Terry G.); Kung, H. (Harriett); DePaula, R. F. (Raymond Felix); Dowden, P. C. (Paul C.); Peterson, E. J. (Eric J.); Stan, L. (Liliana); Emmert, L. A. (Luke A.)

    2001-01-01

    We discuss our progress toward depositing IBAD MgO as a template for subsequent deposition of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) high temperature superconductors on metallic substrates. We have refined the process by improving substrate preparation and by using reflected high-energy electron diffraction (RHEED) to monitor the growth of IBAD MgO films. Here we present results on our work to optimize the IBAD MgO process for continuous processing of meter lengths. High quality IBAD MgO has been deposited on moving metal tape for use in coated conductor fabrication. By incorporating optimized processing parameters, we have been able to deposit films on moving metallic substrates with in-plane mosaic spreads near 8{sup o}. The subsequent pulsed laser deposition (PLD) of 1.5 {micro}m thick YBCO films has resulted in superconducting transport critical current densities >1MA/cm{sup 2} (75K,SF) on small area samples.

  1. Effect of substrate temperature on the texture of MgO films grown by ion beam assisted deposition

    International Nuclear Information System (INIS)

    In this paper, the role of substrate temperature in the crystalline texture of MgO films grown by ion beam assisted deposition (IBAD) is investigated. This study reveals that the best in-plane alignment for MgO films grown on Y2O3/Si is obtained at ∼25 deg. C. At this temperature, MgO films with an in-plane orientation distribution as low as 3.70 full width at half maximum (FWHM) have been attained. MgO films deposited at temperatures higher than 100 deg. C have broad in-plane alignment. Although the deposition at the lowest temperature (-150 deg. C) did not improve the in-plane texture, the acceptable deviation from the optimum ion to molecule ratio for achieving biaxially textured films was the largest. As a trend, the acceptable ion to molecule deviation decreases with increasing substrate temperature. This study is especially important for continuous IBAD MgO depositions where less restrictive conditions are desired

  2. Effect of substrate temperature on the texture of MgO films grown by ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Stan, Liliana; Arendt, Paul N; DePaula, Raymond F; Usov, Igor O; Groves, James R [Superconductivity Technology Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2006-04-15

    In this paper, the role of substrate temperature in the crystalline texture of MgO films grown by ion beam assisted deposition (IBAD) is investigated. This study reveals that the best in-plane alignment for MgO films grown on Y{sub 2}O{sub 3}/Si is obtained at {approx}25 deg. C. At this temperature, MgO films with an in-plane orientation distribution as low as 3.7{sup 0} full width at half maximum (FWHM) have been attained. MgO films deposited at temperatures higher than 100 deg. C have broad in-plane alignment. Although the deposition at the lowest temperature (-150 deg. C) did not improve the in-plane texture, the acceptable deviation from the optimum ion to molecule ratio for achieving biaxially textured films was the largest. As a trend, the acceptable ion to molecule deviation decreases with increasing substrate temperature. This study is especially important for continuous IBAD MgO depositions where less restrictive conditions are desired.

  3. Current progress in YBCO coated conductors using IBAD MgO template layers

    Energy Technology Data Exchange (ETDEWEB)

    Groves, J. R. (James R.); Arendt, P. N. (Paul N.); Foltyn, S. R. (Stephen R.); Jia, Quanxi; Holesinger, T. G. (Terry G.); Emmert, L. A. (Luke A.); DePaula, R. F. (Raymond Felix); Dowden, P. C. (Paul C.); Stan, L. (Liliana); Brewer, R. T. (Rhett T.); Atwater, H. A. (Harry A.)

    2002-01-01

    We present key improvements to growing high quality ({approx}7 degrees {Delta}{phi}) magnesium oxide (MgO) The use of a new layer for IBAD MgO nucleation and reduction in surface roughness of substrates have resulted in better in-plane texture. The processing window for obtaining optimum template texture is very narrow ({approx}10 seconds) using Si,N,. This has been ameliorated by use of an alternate amorphous nucleation layer. The substrate surface roughness has a significant effect on the initial nucleation texture of IBAD MgO films. A surface roughness of -1 nm has resulted in better in-plane texture for IBAD MgO films deposited on metal substrates. We have also implemented a method to quantify IBAD MgO texture using reflected high-energy electron diffraction (RHEED). Utilizing this in situ tool, we have been able to refine deposition parameters to routinely grow films in batch mode that have a {Delta}{phi} of {approx} 7 degrees. Deposited meter lengths have had {Delta}{phi} values from 7-9 degrees with 10% uniformity. One to two micrometer thick YBCO films on these templates have had critical current densities in excess of 1 MA/cm2 at 75 K, in self field.

  4. Integration of biaxally aligned conducting oxides with silicon using ion-beam assisted deposited MgO templates

    Energy Technology Data Exchange (ETDEWEB)

    Park, B. H. (Bae Ho); Groves, J. R. (James R.); DePaula, R. F. (Raymond Felix); Jia, Quanxi; Arendt, P. N. (Paul N.); Emmert, L. A. (Luke A.)

    2001-01-01

    Two conducting oxides, La{sub 0.5}Sr{sub 0.5}CoO{sub 3}(LSCO) and SrRuO{sub 3}, were deposited by pulsed laser ablation onto silicon substrates coated with biaxially textured MgO on an amorphous silicon nitride isolation layer. Comparison is made between templates using just 10 nm of ion-beam assisted deposited (IBAD) MgO and substrates with an additional 100 nm of homoepitaxial MgO. Both of these conducting oxide layers exhibited in-plane and out-of-plane texture, on the order of that obtained by the underlying MgO. The SrRuO{sub 3} was c-axis oriented on both substrates, but exhibited a slightly sharper out-of-plane texture when the homoepitaxial MgO layer was included. On the other hand, the LSCO showed only (100) orientation when deposited directly on the IBAD-MgO templates, whereas a significant (110) peak was observed for films on the homoepitaxial MgO. A simple calculation of the distribution of grain boundary angles, assuming a normal distribution of grains, is also presented.

  5. In-field critical current property of IBAD/PLD coated conductors

    International Nuclear Information System (INIS)

    REBa2Cu3Oy, (RE : rare earth elements, RE123) coated conductors are expected to show high performance in superconducting applications, due to their high mechanical strength and high current density in magnetic fields. Fujikura has developed ion-beam-assisted-deposition (IBAD) and pulsed-laser-deposition (PLD) technique, and today we routinely manufacture coated conductors with length over 500 m and Ic over 500 A/cm-width at 77 K, self field. We have also been able to fabricate long conductors with higher Ic by thickening RE123 layer. Although Ic performances at 77 K, self field are important, but performances in magnetic fields at lower temperatures below 77 K are more important for coil applications. In this work, we evaluated coated conductors with thick RE123 layer in magnetic fields at low temperatures. All samples are fabricated with long length. We measured samples by four-probe transport method at wide temperature range from 77 K to 10 K by using cryo-cooled cryostat. A conductor with 5.5 μm thick RE123 exhibits high Ic values of 937 A/cm-width at 77 K, self field, 637 A/cm-width at 50 K, 5 T and 976 A/cm-width at 40 K, 5 T.

  6. Improvement and characterization of high-reflective and anti-reflective nanostructured mirrors by ion beam assisted deposition for 944 nm high power diode laser

    Science.gov (United States)

    Ghadimi-Mahani, A.; Farsad, E.; Goodarzi, A.; Tahamtan, S.; Abbasi, S. P.; Zabihi, M. S.

    2015-11-01

    Single-layer and multi-layer coatings were applied on the surface of diode laser facets as mirrors. This thin film mirrors were designed, deposited, optimized and characterized. The effects of mirrors on facet passivation and optical properties of InGaAs/AlGaAs/GaAs diode lasers were investigated. High-Reflective (HR) and Anti-Reflective (AR) mirrors comprising of four double-layers of Al2O3/Si and a single layer of Al2O3, respectively, were designed and optimized by Macleod software for 944 nm diode lasers. Optimization of Argon flow rate was studied through Alumina thin film deposition by Ion Beam Assisted Deposition (IBAD) for mirror improvement. The nanostructured HR and AR mirrors were deposited on the front and back facet of the laser respectively, by IBAD system under optimum condition. Atomic Force Microscope (AFM), Vis-IR Spectrophotometer, Field Emission Scanning Electron Microscopy (FESEM) and laser characterization Test (P-I) were used to characterize various properties of mirrors and lasers. AFM images show mirror's root mean square roughness is nearly 1 nm. The Spectrophotometer results of the front facet transmission and the back facet reflection are in good agreement with the simulation results. Optical output power (P) versus driving current (I) characteristics, measured before and after coating the facet, revealed a significant output power enhancement due to optimized AR and HR optical coatings on facets.

  7. Lifetime obtained by ion beam assisted deposition

    International Nuclear Information System (INIS)

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

  8. Polymer-assisted deposition of films

    Science.gov (United States)

    McCleskey,Thomas M.; Burrell,Anthony K.; Jia,Quanxi; Lin,Yuan

    2012-02-28

    A polymer assisted deposition process for deposition of metal nitride films and the like is presented. The process includes solutions of one or more metal precursor and soluble polymers having binding properties for the one or more metal precursor. After a coating operation, the resultant coating is heated at high temperatures under a suitable atmosphere to yield metal nitride films and the like. Such films can be conformal on a variety of substrates including non-planar substrates. In some instances, the films can be epitaxial in structure and can be of optical quality. The process can be organic solvent-free.

  9. Thickness dependence of Ic and Jc of LTG-SmBCO coated-conductor on IBAD-MgO tapes

    International Nuclear Information System (INIS)

    We have reported SmBa2Cu3Oy (SmBCO) films on single crystalline substrates prepared by low-temperature growth (LTG) technique. The LTG-SmBCO films showed high critical current densities in magnetic fields compared with conventional SmBCO films prepared by pulsed laser deposition (PLD) method. In this study, to enhance critical current (Ic) in magnetic field, we fabricated thick LTG-SmBCO films on metal substrates with ion-beam assisted deposition (IBAD)-MgO buffer and estimated the Ic and Jc in magnetic fields. All the SmBCO films showed c-axis orientation and cube-on-cube in-plane texture. Tc of the LTG-SmBCO films were 93.1-93.4 K. Jc and Ic of a 0.5 μm-thick SmBCO film were 3.0 MA/cm2 and 150 A/cm-width at 77 K in self-field, respectively. Those of a 2.0 μm-thick film were 1.6 MA/cm2 and 284 A/cm-width respectively. Although Ic increased with the film thickness increasing up to 2 μm, the Ic tended to be saturated in 300 A/cm-width. From a cross sectional TEM image of the SmBCO film, we recognized a-axis oriented grains and 45o grains and Cu-O precipitates. Because these undesired grains form dead layers, Ic saturated above a certain thickness. We achieved that Ic in magnetic fields of the LTG-SmBCO films with a thickness of 2.0 μm were 88 A/cm-width at 1 T and 28 A/cm-width at 3 T.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-05-31

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

  11. Large area deposition of YBCO thick films for applications in resistive fault current limiting devices

    International Nuclear Information System (INIS)

    The preparation of the switching element of a resistive superconducting fault current limiter requires the up-scaling of deposition techniques for thin YBa2Cu3O7-x (YBCO) films to large areas and high film thicknesses. For a projected 100 kVA limiter model an area of about 400 cm2 and a film thickness of up to 5 μm will be necessary, depending on the material properties like critical current density jc and normal state resistivity ρn. Within a joint project various deposition methods including pulsed laser deposition (PLD), magnetron sputtering (MS), thermal evaporation (TE) and plasma flash evaporation (PFE) are evaluated as possible candidates for the operation of deposition systems capable of coating 20 x 20 cm2 substrates. Both single crystalline wafers and polycrystalline ceramic plates are considered as substrates. To achieve high jc on polycrystalline substrate materials an additional zirconia buffer layer consisting of biaxially orientated crystallites has to be prepared by ion beam assisted deposition (IBAD). In small samples with IBAD buffer critical currents above 105 A cm-2 with a maximum of 1 x 106 A cm-2 have been achieved. The presently available sample sizes depend on the installed systems for YBCO and buffer deposition, respectively and on the commercial availability of the substrate material. The largest samples which have been prepared and characterised have sizes of 1 x 25 cm2 and 5 x 5 cm2 for PLD, 10 x 10 cm2 for TE and IBAD, 2 in. (1 in.=2.54 cm) diameter for MS, and 3 x 7 cm2 for PFE. The corresponding highest film thicknesses are 4.5 μm for PLD, 1.4 μm for TE, 1.6 μm for IBAD and 0.4 μm for MS. (orig.)

  12. Semiconductor assisted metal deposition for nanolithography applications

    Science.gov (United States)

    Rajh, Tijana; Meshkov, Natalia; Nedelijkovic, Jovan M.; Skubal, Laura R.; Tiede, David M.; Thurnauer, Marion

    2001-01-01

    An article of manufacture and method of forming nanoparticle sized material components. A semiconductor oxide substrate includes nanoparticles of semiconductor oxide. A modifier is deposited onto the nanoparticles, and a source of metal ions are deposited in association with the semiconductor and the modifier, the modifier enabling electronic hole scavenging and chelation of the metal ions. The metal ions and modifier are illuminated to cause reduction of the metal ions to metal onto the semiconductor nanoparticles.

  13. Effect of temperature on residual stress and mechanical properties of Ti films prepared by both ion implantation and ion beam assisted deposition

    International Nuclear Information System (INIS)

    Ti films with a thickness of 1.6 μm (group A) and 4.6 μm (group B) were prepared on surface of silicon crystal by metal vapor vacuum arc (MEVVA) ion implantation combined with ion beam assisted deposition (IBAD). Different anneal temperatures ranging from 100 to 500 deg. C were used to investigate effect of temperature on residual stress and mechanical properties of the Ti films. X-ray diffraction (XRD) was used to measure residual stress of the Ti films. The morphology, depth profile, roughness, nanohardness, and modulus of the Ti films were measured by scanning electron microscopy (SEM), scanning Auger nanoprobe (SAN), atomic force microscopy (AFM), and nanoindentation, respectively. The experimental results suggest that residual stress was sensitive to film thickness and anneal temperature. The critical temperatures of the sample groups A and B that residual stress changed from compressive to tensile were 404 and 428 deg. C, respectively. The mean surface roughness and grain size of the annealed Ti films increased with increasing anneal temperature. The values of nanohardness and modulus of the Ti films reached their maximum values near the surface, then, reached corresponding values with increasing depth of the indentation. The mechanism of stress relaxation of the Ti films is discussed in terms of re-crystallization and difference of coefficient of thermal expansion between Ti film and Si substrate.

  14. Electrostatic force assisted deposition of graphene

    Science.gov (United States)

    Liang, Xiaogan

    2011-11-15

    An embodiment of a method of depositing graphene includes bringing a stamp into contact with a substrate over a contact area. The stamp has at least a few layers of the graphene covering the contact area. An electric field is developed over the contact area. The stamp is removed from the vicinity of the substrate which leaves at least a layer of the graphene substantially covering the contact area.

  15. Microreactor-Assisted Solution Deposition for Compound Semiconductor Thin Films

    Directory of Open Access Journals (Sweden)

    Chang-Ho Choi

    2014-05-01

    Full Text Available State-of-the-art techniques for the fabrication of compound semiconductors are mostly vacuum-based physical vapor or chemical vapor deposition processes. These vacuum-based techniques typically operate at high temperatures and normally require higher capital costs. Solution-based techniques offer opportunities to fabricate compound semiconductors at lower temperatures and lower capital costs. Among many solution-based deposition processes, chemical bath deposition is an attractive technique for depositing semiconductor films, owing to its low temperature, low cost and large area deposition capability. Chemical bath deposition processes are mainly performed using batch reactors, where all reactants are fed into the reactor simultaneously and products are removed after the processing is finished. Consequently, reaction selectivity is difficult, which can lead to unwanted secondary reactions. Microreactor-assisted solution deposition processes can overcome this limitation by producing short-life molecular intermediates used for heterogeneous thin film synthesis and quenching the reaction prior to homogeneous reactions. In this paper, we present progress in the synthesis and deposition of semiconductor thin films with a focus on CdS using microreactor-assisted solution deposition and provide an overview of its prospect for scale-up.

  16. Precursors for the polymer-assisted deposition of films

    Science.gov (United States)

    McCleskey, Thomas M.; Burrell, Anthony K.; Jia, Quanxi; Lin, Yuan

    2013-09-10

    A polymer assisted deposition process for deposition of metal oxide films is presented. The process includes solutions of one or more metal precursor and soluble polymers having binding properties for the one or more metal precursor. After a coating operation, the resultant coating is heated at high temperatures to yield metal oxide films. Such films can be epitaxial in structure and can be of optical quality. The process can be organic solvent-free.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-01

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

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

    International Nuclear Information System (INIS)

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

  19. Morphology Simulation for Ion-Assisted Deposition Process

    Institute of Scientific and Technical Information of China (English)

    Jenn-SenLin; Shin-PonJu; Jian-MingLu

    2004-01-01

    The molecular dynamics simulation is applied to investigate the lnfluence of the incident 1on energy ana mclident angular distribution upon ion-assisted deposition process. The Cu-Cu and Ar-Cu interactions are modeled using the many body tight-binding potential and the Moliere potential, respectively, and the interface width is used to characterize the surface roughness properties at both transient and final state conditions. The results show that the surface roughness of the deposition film is lower when more Ar-to-Cu ratio is used at the same incident energy and angle. For the relative low or high incident energy, the film morphologies are not sensitive to the incident angle. However, if the incident energy of the argon ions is too high, the film morphology will be worse than that without using the ion-assisted deposition.

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

    Science.gov (United States)

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

    2015-05-01

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

  1. Hardness and stress of amorphous carbon film deposited by glow discharge and ion beam assisting deposition

    CERN Document Server

    Marques, F C

    2000-01-01

    The hardness and stress of amorphous carbon films prepared by glow discharge and by ion beam assisting deposition are investigated. Relatively hard and almost stress free amorphous carbon films were deposited by the glow discharge technique. On the other hand, by using the ion beam assisting deposition, hard films were also obtained with a stress of the same order of those found in tetrahedral amorphous carbon films. A structural analysis indicates that all films are composed of a sp sup 2 -rich network. These results contradict the currently accepted concept that both stress and hardness are only related to the concentration of sp sup 3 sites. Furthermore, the same results also indicate that the sp sup 2 sites may also contribute to the hardness of the films.

  2. Electric field assisted aerosol assisted chemical vapour deposition of nanostructured metal oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Naik, Anupriya J.T.; Bowman, Christopher; Panjwani, Naitik [Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London WC1H OAJ (United Kingdom); Warwick, Michael E.A. [Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London WC1H OAJ (United Kingdom); UCL Energy Institute, Central House, 14 Upper Woburn Place, London WC1H 0HY (United Kingdom); Binions, Russell, E-mail: r.binions@qmul.ac.uk [Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London WC1H OAJ (United Kingdom); School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)

    2013-10-01

    Nanostructured thin films of tungsten, vanadium and titanium oxides were deposited on gas sensor substrates from the electric field assisted chemical vapour deposition reaction of tungsten hexaphenoxide, vanadyl acetylacetonate and titanium tetraisopropoxide respectively. The electric fields were generated by applying a potential difference between the inter-digitated electrodes of the gas sensor substrates during the deposition. The deposited films were characterised using scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The application of an electric field, encouraged the formation of interesting and unusual nanostructured morphologies, with a change in scale length and island packing. It was also noted that crystallographic orientation of the films could be controlled as a function of electric field type and strength. The gas sensor properties of the films were also examined; it was found that a two to three fold enhancement in the gas response could be observed from sensors with enhanced morphologies compared to control sensors grown without application of an electric field. - Highlights: • Electric field assisted chemical vapour deposition method • Ability to create high surface area film architectures • Can produce enhanced sensor response • Good control over film properties.

  3. Laser-assisted deposition of thin C60 films

    DEFF Research Database (Denmark)

    Schou, Jørgen; Canulescu, Stela; Fæster, Søren

    Metal and metal oxide films with controlled thickness from a fraction of a monolayer up more than 1000 nm and known stoichiometry can be produced by pulsed laser deposition (PLD) relatively easily, and (PLD) is now a standard technique in all major research laboratories within materials science....... However, organic materials are usually not well suited for direct laser irradiation, since the organic molecules may suffer from fragmentation by the laser light. We have, therefore, explored the possible fragmentation of organic molecules by attempting to produce thin films of C60 which is a strongly...... bound carbon molecule with a well-defined mass (M = 720 amu) and therefore a good, organic test molecule. C60 fullerene thin films of average thickness of more than 100 nm was produced in vacuum by matrix-assisted pulsed laser evaporation (MAPLE). A 355 nm Nd:YAG laser was directed onto a frozen target...

  4. Plasma and Ion Assistance in Physical Vapor Deposition: AHistorical Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2007-02-28

    Deposition of films using plasma or plasma-assist can betraced back surprisingly far, namely to the 18th century for arcs and tothe 19th century for sputtering. However, only since the 1960s thecoatings community considered other processes than evaporation for largescale commercial use. Ion Plating was perhaps the first importantprocess, introducing vapor ionization and substrate bias to generate abeam of ions arriving on the surface of the growing film. Ratherindependently, cathodic arc deposition was established as an energeticcondensation process, first in the former Soviet Union in the 1970s, andin the 1980s in the Western Hemisphere. About a dozen various ion-basedcoating technologies evolved in the last decades, all characterized byspecific plasma or ion generation processes. Gridded and gridless ionsources were taken from space propulsion and applied to thin filmdeposition. Modeling and simulation have helped to make plasma and ionseffects to be reasonably well understood. Yet--due to the complex, oftennon-linear and non-equilibrium nature of plasma and surfaceinteractions--there is still a place for the experience plasma"sourcerer."

  5. Electrical properties of DLC- (n, p)-Si heterojunctions fabricated by ion-assisted plasma-enhanced deposition and pulsed laser deposition methods

    Science.gov (United States)

    Panosyan, Zhosef R.; Voskanyan, Serjik S.; Yengibaryan, Yerem V.; Avjyan, Karapet E.; Khachatryan, Ashot M.; Matevosyan, Lenrik A.

    2010-10-01

    Electrical characteristics of DLC- (n, p)-Si heterojunctions fabricated by ion-assisted plasma-enhanced deposition and pulsed laser deposition methods were investigated. The mechanisms of carrier flow across the fabricated junctions were analyzed. Keywords: ion-assisted plasma-enhanced deposition, pulsed laser deposition, DLC- (n, p)-Si heterojunctions, currentvoltage & capacitance- voltage characteristics.

  6. Structural and electrical properties of electric field assisted spray deposited pea structured ZnO film

    Science.gov (United States)

    Chaturvedi, Neha; Swami, Sanjay Kumar; Dutta, Viresh

    2016-05-01

    Spray deposition of ZnO film was carried out. The uneven growth of ZnO nanostructures is resulted for spray deposited ZnO film. Application of DC voltage (1000V) during spray deposition provides formation of pea like structures with uniform coverage over the substrate. Electric field assisted spray deposition provides increased crystallinity with reduced resistivity and improved mobility of the ZnO film as compared to spray deposited ZnO film without electric field. This with large area deposition makes the process more efficient than other techniques.

  7. Activator-assisted electroless deposition of copper nanostructured films

    Institute of Scientific and Technical Information of China (English)

    Varsha R. Mehto; R. K. Pandey

    2014-01-01

    This paper showed simple and effective synthesis of copper nanoparticles within controlled diameter using direct electroless deposition on glass substrates, following the sensitization and activation steps. Electroless-deposited metals, such as Cu, Co, Ni, and Ag, and their alloys had many advantages in micro- and nanotechnologies. The structural, morphological, and optical properties of copper deposits were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-Vis spectroscopy. The structural data was further analyzed using the Rietveld refinement program. Structural studies reveal that the deposited copper prefers a (111) orientation. AFM studies suggest the deposited materials form compact, uniform, and nanocrystalline phases with a high tendency to self-organize. The data show that the particle size can be controlled by controlling the activator concentration. The absorption spectra of the as-deposited copper nanoparticles reveal that the plasmonic peak broadens and exhibits a blue shift with decreasing particle size.

  8. Mechanical and transport properties of IBAD/EDDC-SmBCO coated conductor tapes during fatigue loading

    Science.gov (United States)

    Shin, Hyung-Seop; Dedicatoria, Marlon J.

    2011-06-01

    In electrical devices like superconducting motor, generator and SMES, HTS coated conductor (CC) tapes will be subjected to alternating stress or strain during manufacturing and operation. The repeated loading will affect the mechanical integrity and eventually the electrical transport property of CC tapes. Therefore in such applications, electro-mechanical property of CC tapes should be evaluated. In this study, the endurance of an IBAD/EDDC-SmBCO CC tape under high-cycle fatigue loading has been evaluated. Applied maximum stress and fatigue life ( S-N) relation was obtained at 77 K. The mechanical properties and the critical current, I c, of the sample under fatigue loading were investigated at 77 K. Considering the practical operating environment, the effect of the stress ratio R, on the degradation behavior of I c under fatigue loading was also examined.

  9. Gradient SiNx IBAD coating: preparation and measurement of concentration profile

    International Nuclear Information System (INIS)

    Preparation of gradient SiNx coating by the ion beam assisted deposition method with high ion energy is described. Special shape of the concentration of nitrogen in the coating was chosen and constructed. Concentration profile was constructed in three steps with different ratios of nitrogen and silicon atom fluxes. Ion energy was 90 keV. Concentration profile was measured by RBS (Rutherford Back Scattering) method. (author). 1 ref., 2 figs

  10. In situ biaxial texture analysis of MGO films during growth on amorphous substrates by ion beam-assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Brewer, R. T. (Rhett T.); Arendt, P. N. (Paul N.); Atwater, H. A. (Harry A.); Groves, J. R. (James R.)

    2001-01-01

    We used a previously reported kinematical electron scattering model to develop a RHEED based method for performing quantitative analysis of mosaic polycrystalline thin film in-plane and out-of-plain grain orientation distributions. RHEED based biaxial texture measurements are compared to X-Ray and transmission electron microscopy measurements to establish the validity of the RHEED analysis method. In situ RHEED analysis reveals that the out of plane orientation distribution starts out very broad, and then decreases during IBAD MgO growth. Other results included evidence that the in-plane orientation distribution narrows, the grain size increases, and the film roughens as film thickness increases during IBAD MgO growth. Homoepitaxy of MgO improves the biaxial texture of the IBAD layer, making X-ray measurements of IBAD films with an additional homoepitaxial layer not quantitatively representative of the IBAD layer. Systematic offsets between RHEED analysis and X-ray measurements of biaxial texture, coupled with evidence that biaxial texture improves with increasing film thickness, indicate that RHEED is a superior technique for probing surface biaxial texture.

  11. Light-assisted deposition of CdS thin films

    Science.gov (United States)

    Bacaksiz, E.; Novruzov, V.; Karal, H.; Yanmaz, E.; Altunbas, M.; Kopya, A. I.

    2001-11-01

    The effects of white light illumination during the deposition of CdS thin films in a quasi-closed volume on the structural, photoelectrical and optical properties are investigated. The films were highly c-axis oriented with an increasing intensity of (002) reflection as the illumination increases. The room temperature resistivity values of the CdS films decreased in the range of 107-104 Ω cm. The photosensitivity in the fundamental absorption region and the transparency in the transmission region considerably increased as the illumination increased. Under 100 mW cm-2 insolation, the efficiencies of the CdS/CdTe solar cells based on CdS window materials which were deposited: (1) in the dark; and (2) under an illumination of 150 mW cm-2 were found to be 1.8% and 7.3%, respectively.

  12. Aerosol assisted depositions of polymers using an atomiser delivery system.

    Science.gov (United States)

    Crick, Colin R; Clausen-Thue, Victoria; Parkin, Ivan P

    2011-09-01

    The hydrophobicity, robustness and anti-microbial properties of Sylgard 184 polymer films deposited via AACVD were optimised by using aerosol droplets from an atomiser delivery system, polymer coating substrates and the swell encapsulation of methylene blue. By using an atomiser deposition system (average droplet size 0.35 microm) rather than a misting aerosol system (45 microm) lead to a surface with smaller surface features, which improved hydrophobicity (water contact angle 165 degrees) in addition to increasing the films transparency from ca 10 to 65%. Pre-treating the substrates with the same Sylgard 184 elastomer lead to a highly consistent surface hydrophobicity and an increase in average water contact angle measured (169 degrees). This paper shows the first example of dye incorporation in a CVD derived polymer film-these films have potential as antimicrobial surfaces.

  13. Photocatalytic activity of tin-doped TiO{sub 2} film deposited via aerosol assisted chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Chua, Chin Sheng, E-mail: cschua@simtech.a-star.edu.sg [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 (Singapore); Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, 638075 (Singapore); Tan, Ooi Kiang; Tse, Man Siu [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 (Singapore); Ding, Xingzhao [Singapore Institute of Manufacturing Technology, 71 Nanyang Drive, 638075 (Singapore)

    2013-10-01

    Tin-doped TiO{sub 2} films are deposited via aerosol assisted chemical vapor deposition using a precursor mixture composing of titanium tetraisopropoxide and tetrabutyl tin. The amount of tin doping in the deposited films is controlled by the volume % concentration ratio of tetrabutyl tin over titanium tetraisopropoxide in the mixed precursor solution. X-ray diffraction analysis results reveal that the as-deposited films are composed of pure anatase TiO{sub 2} phase. Red-shift in the absorbance spectra is observed attributed to the introduction of Sn{sup 4+} band states below the conduction band of TiO{sub 2}. The effect of tin doping on the photocatalytic property of TiO{sub 2} films is studied through the degradation of stearic acid under UV light illumination. It is found that there is a 10% enhancement on the degradation rate of stearic acid for the film with 3.8% tin doping in comparison with pure TiO{sub 2} film. This improvement of photocatalytic performance with tin incorporation could be ascribed to the reduction of electron-hole recombination rate through charge separation and an increased amount of OH radicals which are crucial for the degradation of stearic acid. Further increase in tin doping results in the formation of recombination site and large anatase grains, which leads to a decrease in the degradation rate. - Highlights: ► Deposition of tin-doped TiO{sub 2} film via aerosol assisted chemical vapor depositionDeposited anatase films show red-shifted in UV–vis spectrum with tin-dopants. ► Photoactivity improves at low tin concentration but reduces at higher concentration. ► Improvement in photoactivity due to bandgap narrowing from Sn{sup 4+} band states ► Maximum photoactivity achieved occurs for films with 3.8% tin doping.

  14. Functional porphyrin thin films deposited by matrix assisted pulsed laser evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Atomistilor 409, Bucharest-Magurele (Romania); Popescu, C.; Popescu, A.C.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Atomistilor 409, Bucharest-Magurele (Romania); Ciucu, A.A. [Univeristy of Bucharest, Chemistry Department, Bucharest (Romania); Andronie, A.; Iordache, S.; Stamatin, I. [University of Bucharest, 3 Nano-SAE Research Center, P.O. Box MG-38, Bucharest-Magurele (Romania); Fagadar-Cosma, E. [Institute of Chemistry Timisoara of Romanian Academy, Department of Organic Chemistry, 300223 Timisoara (Romania); Chrisey, D.B. [Rensselaer Polytechnic Institute, School of Engineering, Department of Materials Science and Engineering, Troy 12180-3590, NY (United States)

    2010-05-25

    We report the first successful deposition of functionalized and nanostructured Zn(II)- and Co(II)-metalloporphyrin thin films by matrix assisted pulsed laser evaporation onto silicon wafers, quartz plates and screen-printed electrodes. The deposited nanostructures have been characterized by Raman spectrometry and cyclic voltammetry. The novelty of our contribution consists of the evaluation of the sensitivity of the MAPLE-deposited Zn(II)- and Co(II)-metalloporphyrin thin films on screen-printed carbon nanotube electrodes when challenged with dopamine.

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

    International Nuclear Information System (INIS)

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

  16. UV and RIR matrix assisted pulsed laser deposition of organic MEH-PPV films

    DEFF Research Database (Denmark)

    Christensen, Bo Toftmann; Papantonalis, M.R.; Auyeung, R.C.Y.;

    2004-01-01

    A comparative study of thin film production based on gentle laser-ablation techniques has been carried out with the luminescent polymer poly [2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene]. Using a free-electron laser films were made by resonant infrared pulsed laser deposition (RIR......-PLD). For the first time resonant infrared matrix assisted pulsed laser evaporation (RIR-MAPLE) was successfully demonstrated on a luminescent polymer system. In addition to this, an excimer laser has been used for UV-MAPLE depositions at 193 and 248-nm irradiation. Films deposited onto NaCl and quartz substrates...... were analyzed by Fourier transform infrared spectroscopy, UV-visible absorbance and photoluminescence. Photoluminescent material was deposited by RIR-MAPLE and 248-nm MAPLE, while the RIR-PLD and 193-nm-MAPLE depositions displayed the smoothest surfaces but did not show photoluminescence. (C) 2003...

  17. Air-assisted boom sprayer and spray deposition on bean plants

    Directory of Open Access Journals (Sweden)

    Bauer Fernando Cesar

    2003-01-01

    Full Text Available The development of safe pesticide application techniques with low volume rates, frequency and spray drift, along with the need to obtain better control level of crop pest control levels, justify the air-assistance in boom sprayers. The aim of this research was to evaluate the spray deposition on bean plants with different nozzles and volume rates by air-assisted and non-assisted sprayers. A completely randomized experiment was carried out using copper oxide as a tracer (50% metalic copper for deposit evaluation. The artificial targets were fixed on the upper and under-side of the leaflets, at the top and lower third of the same plants under the spray boom. After application, targets were washed individually with an extracting solution of nitric acid (1.0 mol L-1. The tracer deposition on the artificial targets was quantified by atomic absorption spectrofotometry. The effects of air-assisted spray were not significant in relation to spray deposition 48 days after emergence of the bean plants.

  18. Microwave assisted apatite coating deposition on Ti6Al4V implants.

    Science.gov (United States)

    Zhou, Huan; Nabiyouni, Maryam; Bhaduri, Sarit B

    2013-10-01

    In this work we report a novel microwave assisted technology to deposit a uniform, ultra-thin apatite coating without any cracks on titanium implants in minutes. This method comprises of conventional biomimetic coating in synergism with microwave irradiation to result in alkaline earth phosphate nucleation. The microwave assisted coating process mainly follows the initial stages of biomimetic coating until the step of the Ca-P nuclei formation. After that, due to microwave irradiation more Ca-P nuclei are formed to cover the whole surface of the implant instead of the growth of deposited Ca-P nuclei to Ca-P globules and coatings. It is interesting to note the doping of Mg(2+) to Ca-P apatite coating can significantly change the properties and performances of as-deposited coatings. The hydrophilicity, physical properties, bioactivity, cell adhesion, and growth capability of as-deposited microwave assisted coatings were investigated. The study shows that this coating technology has great potential in biomedical applications. Additionally, since biomimetic coating can be applied to series of implant materials such as polymer, metals and glass, it is expected this microwave assisted coating technology can also be applied to these materials if they can remains stable at 100 °C, the boiling point of water.

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

    CERN Document Server

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

    2002-01-01

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

  20. Aspects of the SrO-CuO-TiO2 Ternary System Related to the Deposition of SrTiO3 and Copper-Doped SrTiO3 Thin-Film Buffer Layers

    Energy Technology Data Exchange (ETDEWEB)

    A. Ayala

    2004-12-20

    YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) coated conductors are promising materials for large-scale superconductivity applications. One version of a YBCO coated conductor is based on ion beam assisted deposition (IBAD) of magnesium oxide (MgO) onto polycrystalline metal substrates. SrTiO{sub 3} (STO) is often deposited by physical vapor deposition (PVD) methods as a buffer layer between the YBCO and IBAD MgO due to its chemical stability and lattice mismatch of only {approx}1.5% with YBCO. In this work, some aspects of the stability of STO with respect to copper (Cu) and chemical solution deposition of STO on IBAD MgO templates were examined. Solubility limits of Cu in STO were established by processing Cu-doped STO powders by conventional bulk preparation techniques. The maximum solubility of Cu in STO was {approx}1% as determined by transmission electron microscopy (TEM) and Rietveld refinements of x-ray diffraction (XRD) data. XRD analysis, performed in collaboration with NIST, on powder compositions on the STO/SrCuO{sub 2} tie line did not identify any ternary phases. SrCu{sub 0.10}Ti{sub 0.90}O{sub y} buffer layers were prepared by pulsed laser deposition (PLD) and CSD on IBAD MgO flexible metallic textured tapes. TEM analysis of a {approx}100 nm thick SrCu{sub 0.10}Ti{sub 0.90}O{sub y} buffer layer deposited by PLD showed a smooth Cu-doped STO/MgO interface. A {approx}600 nm thick YBCO film, deposited onto the SrCu{sub 0.10}Ti{sub 0.90}O{sub y} buffer by PLD, exhibited a T{sub c} of 87 K and critical current density (J{sub c}) of {approx}1 MA/cm{sup 2}. STO and Cu-doped STO thin films by CSD were {approx}30 nm thick. The in plane alignment (FWHM) after deposition of the STO improved by {approx}1{sup o} while it degraded by {approx}2{sup o} with the SrCu{sub 0.05}TiO{sub y} buffer. YBCO was deposited by PLD on the STO and SrCu{sub 0.05}TiO{sub y} buffers. The in plane alignment (FWHM) of the YBCO with the STO buffer layer slightly improved while that of the

  1. Growth mechanism of planar or nanorod structured tungsten oxide thin films deposited via aerosol assisted chemical vapour deposition (AACVD)

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Min; Blackman, Chris [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

    2015-07-15

    Aerosol assisted chemical vapour deposition (AACVD) is used to deposit tungsten oxide thin films from tungsten hexacarbonyl (W(CO){sub 6}) at 339 to 358 C on quartz substrate. The morphologies of as-deposited thin films, which are comprised of two phases (W{sub 25}O{sub 73} and W{sub 17}O{sub 47}), vary from planar to nanorod (NR) structures as the distance from the inlet towards the outlet of the reactor is traversed. This is related to variation of the actual temperature on the substrate surface (ΔT = 19 C), which result in a change in growth mode due to competition between growth rate (perpendicular to substrate) and nucleation rate (parallel to substrate). When the ratio of perpendicular growth rate to growth rate contributed by nucleation is higher than 7.1, the as-deposited tungsten oxide thin film forms as NR. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. CdS thin films prepared by laser assisted chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, L.V.; Mendivil, M.I.; Garcia Guillen, G.; Aguilar Martinez, J.A. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Krishnan, B. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); CIIDIT – Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Avellaneda, D.; Castillo, G.A.; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Shaji, S., E-mail: sshajis@yahoo.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); CIIDIT – Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)

    2015-05-01

    Highlights: • CdS thin films by conventional CBD and laser assisted CBD. • Characterized these films using XRD, XPS, AFM, optical and electrical measurements. • Accelerated growth was observed in the laser assisted CBD process. • Improved dark conductivity and good photocurrent response for the LACBD CdS. - Abstract: In this work, we report the preparation and characterization of CdS thin films by laser assisted chemical bath deposition (LACBD). CdS thin films were prepared from a chemical bath containing cadmium chloride, triethanolamine, ammonium hydroxide and thiourea under various deposition conditions. The thin films were deposited by in situ irradiation of the bath using a continuous laser of wavelength 532 nm, varying the power density. The thin films obtained during deposition of 10, 20 and 30 min were analyzed. The changes in morphology, structure, composition, optical and electrical properties of the CdS thin films due to in situ irradiation of the bath were analyzed by atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis spectroscopy. The thin films obtained by LACBD were nanocrystalline, photoconductive and presented interesting morphologies. The results showed that LACBD is an effective synthesis technique to obtain nanocrystalline CdS thin films having good optoelectronic properties.

  3. CdS thin films prepared by laser assisted chemical bath deposition

    International Nuclear Information System (INIS)

    Highlights: • CdS thin films by conventional CBD and laser assisted CBD. • Characterized these films using XRD, XPS, AFM, optical and electrical measurements. • Accelerated growth was observed in the laser assisted CBD process. • Improved dark conductivity and good photocurrent response for the LACBD CdS. - Abstract: In this work, we report the preparation and characterization of CdS thin films by laser assisted chemical bath deposition (LACBD). CdS thin films were prepared from a chemical bath containing cadmium chloride, triethanolamine, ammonium hydroxide and thiourea under various deposition conditions. The thin films were deposited by in situ irradiation of the bath using a continuous laser of wavelength 532 nm, varying the power density. The thin films obtained during deposition of 10, 20 and 30 min were analyzed. The changes in morphology, structure, composition, optical and electrical properties of the CdS thin films due to in situ irradiation of the bath were analyzed by atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis spectroscopy. The thin films obtained by LACBD were nanocrystalline, photoconductive and presented interesting morphologies. The results showed that LACBD is an effective synthesis technique to obtain nanocrystalline CdS thin films having good optoelectronic properties

  4. Plasma Assisted Chemical Vapour Deposition – Technological Design Of Functional Coatings

    Directory of Open Access Journals (Sweden)

    Januś M.

    2015-06-01

    Full Text Available Plasma Assisted Chemical Vapour Deposition (PA CVD method allows to deposit of homogeneous, well-adhesive coatings at lower temperature on different substrates. Plasmochemical treatment significantly impacts on physicochemical parameters of modified surfaces. In this study we present the overview of the possibilities of plasma processes for the deposition of diamond-like carbon coatings doped Si and/or N atoms on the Ti Grade2, aluminum-zinc alloy and polyetherketone substrate. Depending on the type of modified substrate had improved the corrosion properties including biocompatibility of titanium surface, increase of surface hardness with deposition of good adhesion and fine-grained coatings (in the case of Al-Zn alloy and improving of the wear resistance (in the case of PEEK substrate.

  5. Ion-Bombardment of X-Ray Multilayer Coatings - Comparison of Ion Etching and Ion Assisted Deposition

    NARCIS (Netherlands)

    Puik, E. J.; van der Wiel, M. J.; Zeijlemaker, H.; Verhoeven, J.

    1991-01-01

    The effects of two forms of ion bombardment treatment on the reflectivity of multilayer X-ray coatings were compared: ion etching of the metal layers, taking place after deposition, and ion bombardment during deposition, the so-called ion assisted deposition. The ion beam was an Ar+ beam of 200 eV,

  6. Ion beam assisted deposition of organic molecules: a physical way to realize OLED structures

    Science.gov (United States)

    Moliton, André; Antony, Rémi; Troadec, David; Ratier, Bernard

    2000-05-01

    We demonstrate how the quantum efficiency of an organic light-emitting diode can be improved by a physical way based on the ion beam assisted deposition: the recombination current can be increased by an enhancement of the minority carrier injection while the total current can be decreased by generation of electron traps which reduced the majority current. The quantum efficiency of fluorescence can be also improved by a layer densification with a limitation of the nonradiative centers. As a result, the quantum efficiency of the structure ITO/Helium assisted Alq3/unassisted Alq3/Ca/Al is improved (by around a factor 10) in relation with a virgin structure.

  7. Laser-assisted chemical liquid-phase deposition of metals for micro- and optoelectronics

    OpenAIRE

    Kordás, K. (Krisztián)

    2002-01-01

    Abstract The demands toward the development of simple and cost-effective fabrication methods of metallic structures with high lateral resolution on different substrates - applied in many fields of technology, such as in microelectronics, optoelectronics, micromechanics as well as in sensor and actuator applications - gave the idea to perform this research. Due to its simplicity, laser-assisted chemical liquid-phase deposition (LCLD) has been investigated and applied for the metallization o...

  8. Aerosol assisted chemical vapor deposition using nanoparticle precursors: a route to nanocomposite thin films.

    Science.gov (United States)

    Palgrave, Robert G; Parkin, Ivan P

    2006-02-01

    Gold nanoparticle and gold/semiconductor nanocomposite thin films have been deposited using aerosol assisted chemical vapor deposition (CVD). A preformed gold colloid in toluene was used as a precursor to deposit gold films onto silica glass. These nanoparticle films showed the characteristic plasmon absorption of Au nanoparticles at 537 nm, and scanning electron microscopic (SEM) imaging confirmed the presence of individual gold particles. Nanocomposite films were deposited from the colloid concurrently with conventional CVD precursors. A film of gold particles in a host tungsten oxide matrix resulted from co-deposition with [W(OPh)(6)], while gold particles in a host titania matrix resulted from co-deposition with [Ti(O(i)Pr)(4)]. The density of Au nanoparticles within the film could be varied by changing the Au colloid concentration in the original precursor solution. Titania/gold composite films were intensely colored and showed dichromism: blue in transmitted light and red in reflected light. They showed metal-like reflection spectra and plasmon absorption. X-ray photoelectron spectroscopy and energy-dispersive X-ray analysis confirmed the presence of metallic gold, and SEM imaging showed individual Au nanoparticles embedded in the films. X-ray diffraction detected crystalline gold in the composite films. This CVD technique can be readily extended to produce other nanocomposite films by varying the colloids and precursors used, and it offers a rapid, convenient route to nanoparticle and nanocomposite thin films. PMID:16448130

  9. Aerosol-Assisted Chemical Vapor Deposited Thin Films for Space Photovoltaics

    Science.gov (United States)

    Hepp, Aloysius F.; McNatt, Jeremiah; Dickman, John E.; Jin, Michael H.-C.; Banger, Kulbinder K.; Kelly, Christopher V.; AquinoGonzalez, Angel R.; Rockett, Angus A.

    2006-01-01

    Copper indium disulfide thin films were deposited via aerosol-assisted chemical vapor deposition using single source precursors. Processing and post-processing parameters were varied in order to modify morphology, stoichiometry, crystallography, electrical properties, and optical properties in order to optimize device-quality material. Growth at atmospheric pressure in a horizontal hot-wall reactor at 395 C yielded best device films. Placing the susceptor closer to the evaporation zone and flowing a more precursor-rich carrier gas through the reactor yielded shinier, smoother, denser-looking films. Growth of (112)-oriented films yielded more Cu-rich films with fewer secondary phases than growth of (204)/(220)-oriented films. Post-deposition sulfur-vapor annealing enhanced stoichiometry and crystallinity of the films. Photoluminescence studies revealed four major emission bands (1.45, 1.43, 1.37, and 1.32 eV) and a broad band associated with deep defects. The highest device efficiency for an aerosol-assisted chemical vapor deposited cell was 1.03 percent.

  10. Ion assisted deposition of SiO2 film from silicon

    Science.gov (United States)

    Pham, Tuan. H.; Dang, Cu. X.

    2005-09-01

    Silicon dioxide, SiO2, is one of the preferred low index materials for optical thin film technology. It is often deposited by electron beam evaporation source with less porosity and scattering, relatively durable and can have a good laser damage threshold. Beside these advantages the deposition of critical optical thin film stacks with silicon dioxide from an E-gun was severely limited by the stability of the evaporation pattern or angular distribution of the material. The even surface of SiO2 granules in crucible will tend to develop into groove and become deeper with the evaporation process. As the results, angular distribution of the evaporation vapor changes in non-predicted manner. This report presents our experiments to apply Ion Assisted Deposition process to evaporate silicon in a molten liquid form. By choosing appropriate process parameters we can get SiO2 film with good and stable property.

  11. The minimum amount of "matrix " needed for matrix-assisted pulsed laser deposition of biomolecules

    DEFF Research Database (Denmark)

    Tabetah, Marshall; Matei, Andreea; Constantinescu, Catalin;

    2014-01-01

    The ability of matrix-assisted pulsed laser evaporation (MAPLE) technique to transfer and deposit high-quality thin organic, bioorganic, and composite films with minimum chemical modification of the target material has been utilized in numerous applications. One of the outstanding problems in MAPLE...... film deposition, however, is the presence of residual solvent (matrix) codeposited with the polymer material and adversely affecting the quality of the deposited films. In this work, we investigate the possibility of alleviating this problem by reducing the amount of matrix in the target. A series...... of coarse-grained molecular dynamics simulations are performed for a model lysozyme-water system, where the water serves the role of volatile "matrix" that drives the ejection of the biomolecules. The simulations reveal a remarkable ability of a small (5-10 wt %) amount of matrix to cause the ejection...

  12. Radio-frequency assisted pulsed laser deposition of nanostructured WOx films

    International Nuclear Information System (INIS)

    The synthesis of tungsten oxide films with large surface area is promising for gas sensing applications. Thin WOx films were obtained by radio-frequency assisted pulsed laser deposition (RF-PLD). A tungsten target was ablated at 700 and 900 Pa in reactive oxygen, or in a 50% mixed oxygen-helium atmosphere at the same total pressure values. Corning glass was used as substrate, at temperatures including 673, 773 and 873 K. Other deposition parameters such as laser fluence (4.5 J cm-2), laser wavelength (355 nm), radiofrequency power (150 W), target to substrate distance (4 cm), laser spot area (0.7 mm2), and number of laser shots (12,000) were kept fixed. The sensitivity on the deposition conditions of morphology, nanostructure, bond coordination, and roughness of the obtained films were analyzed by scanning and transmission electron microscopy, micro-Raman spectroscopy, and atomic force microscopy.

  13. Effects of Processing Variables on Tantalum Nitride by Reactive-Ion-Assisted Magnetron Sputtering Deposition

    Science.gov (United States)

    Wei, Chao‑Tsang; Shieh, Han‑Ping D.

    2006-08-01

    The binary compound tantalum nitride (TaN) and ternary compounds tantalum tungsten nitrides (Ta1-xWxNy) exhibit interesting properties such as high melting point, high hardness, and chemical inertness. Such nitrides were deposited on a tungsten carbide (WC) die and silicon wafers by ion-beam-sputter evaporation of the respective metal under nitrogen ion-assisted deposition (IAD). The effects of N2/Ar flux ratio, post annealing, ion-assisted deposition, deposition rate, and W doping in coating processing variables on hardness, load critical scratching, oxidation resistance, stress and surface roughness were investigated. The optimum N2/Ar flux ratios in view of the hardness and critical load of TaN and Ta1-xWxNy films were ranged from 0.9 to 1.0. Doping W into TaN to form Ta1-xWxNy films led significant increases in hardness, critical load, oxidation resistance, and reduced surface roughness. The optimum doping ratio was [W/(W+Ta)]=0.85. From the deposition rate and IAD experiments, the stress in the films is mainly contributed by sputtering atoms. The lower deposition rate at a high N2/Ar flux ratio resulted in a higher compressive stress. A high compressive residual stress accounts for a high hardness. The relatively high compressive stress was attributed primarily to peening by atoms, ions and electrons during film growth, the Ta1-xWxNy films showed excellent hardness and strength against a high temperature, and sticking phenomena can essentially be avoided through their use. Ta1-xWxNy films showed better performance than the TaN film in terms of mechanical properties and oxidation resistance.

  14. Aerosol assisted atmospheric pressure chemical vapor deposition of silicon thin films using liquid cyclic hydrosilanes

    International Nuclear Information System (INIS)

    Silicon (Si) thin films were produced using an aerosol assisted atmospheric pressure chemical vapor deposition technique with liquid hydrosilane precursors cyclopentasilane (CPS, Si5H10) and cyclohexasilane (CHS, Si6H12). Thin films were deposited at temperatures between 300 and 500 °C, with maximum observed deposition rates of 55 and 47 nm/s for CPS and CHS, respectively, at 500 °C. Atomic force microscopic analyses of the films depict smooth surfaces with roughness of 4–8 nm. Raman spectroscopic analysis indicates that the Si films deposited at 300 °C and 350 °C consist of a hydrogenated amorphous Si (a-Si:H) phase while the films deposited at 400, 450, and 500 °C are comprised predominantly of a hydrogenated nanocrystalline Si (nc-Si:H) phase. The wide optical bandgaps of 2–2.28 eV for films deposited at 350–400 °C and 1.7–1.8 eV for those deposited at 450–500 °C support the Raman data and depict a transition from a-Si:H to nc-Si:H. Films deposited at 450 oC possess the highest photosensitivity of 102–103 under AM 1.5G illumination. Based on the growth model developed for other silanes, we suggest a mechanism that governs the film growth using CPS and CHS. - Highlights: • Si films via AA-APCVD are realized using cyclopentasilane (CPS) and cyclohexasilane (CHS). • Low activation energies of CPS and CHS allow Si thin films at low temperatures (300 °C). • High growth rates of 47–55 nm/s were obtained at 500 °C • Near device quality Si thin films with 2–3 orders of photosensitivity • Si thin films via AA-APCVD are amenable to continuous roll-to-roll manufacturing

  15. Growth Assisted by Glancing Angle Deposition: A New Technique to Fabricate Highly Porous Anisotropic Thin Films.

    Science.gov (United States)

    Sanchez-Valencia, Juan Ramon; Longtin, Remi; Rossell, Marta D; Gröning, Pierangelo

    2016-04-01

    We report a new methodology based on glancing angle deposition (GLAD) of an organic molecule in combination with perpendicular growth of a second inorganic material. The resulting thin films retain a very well-defined tilted columnar microstructure characteristic of GLAD with the inorganic material embedded inside the columns. We refer to this new methodology as growth assisted by glancing angle deposition or GAGLAD, since the material of interest (here, the inorganic) grows in the form of tilted columns, though it is deposited under a nonglancing configuration. As a "proof of concept", we have used silver and zinc oxide as the perpendicularly deposited material since they usually form ill-defined columnar microstructures at room temperature by GLAD. By means of our GAGLAD methodology, the typical tilted columnar microstructure can be developed for materials that otherwise do not form ordered structures under conventional GLAD. This simple methodology broadens significantly the range of materials where control of the microstructure can be achieved by tuning the geometrical deposition parameters. The two examples presented here, Ag/Alq3 and ZnO/Alq3, have been deposited by physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD), respectively: two different vacuum techniques that illustrate the generality of the proposed technique. The two type of hybrid samples present very interesting properties that demonstrate the potentiality of GAGLAD. On one hand, the Ag/Alq3 samples present highly optical anisotropic properties when they are analyzed with linearly polarized light. To our knowledge, these Ag/Alq3 samples present the highest angular selectivity reported in the visible range. On the other hand, ZnO/Alq3 samples are used to develop highly porous ZnO thin films by using Alq3 as sacrificial material. In this way, antireflective ZnO samples with very low refractive index and extinction coefficient have been obtained. PMID:26954074

  16. Ion-assisted doping of 2-6 compounds during physical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Bube, R H [Stanford Univ., CA (USA). Dept. of Materials Science and Engineering

    1990-07-01

    This report describes a research program to (1) investigate ion-assisted doping during chemical vapor deposition of CdTe and (2) determine the influence of co-depositing ionized dopant atoms in the growth and structural and photoelectronic properties of the deposited films. In p-CdTe homo-epitaxial films, we controlled doping up to about 6 {times} 10{sup 16} cm{sup {minus}3} and 2 {times} 10{sup 17} cm{sub {minus}3} or ion-assisted depositions with As and P ions, respectively. At a growth rate of approximately 0.1 {mu}m/min, a substrate temperature of 400{degree}C, and ion energy of 60 eV, a maximum doping density was found near an ion current of 0.6{mu}A/cm{sup 2}. Related studies included elucidating the role of low-energy ion damage in the ion-assisted doping process, and investigating the decrease in carrier density near the surface of p-CdTe upon heating in vacuum, H{sub 2}, or Ar. We demonstrate the ability to make carrier density profiles and to grade junctions, and we present preliminary results from polycrystalline p-CdTe films grown on graphite and alumina substrates. We also present solar cells prepared using the p-CdTe as the collector area and n-CdS as the window layer, and we examine their photovoltaic parameters for different carrier densities and configurations in p-CdTe. 91 refs., 44 figs., 5 tabs.

  17. Ion assisted deposition with low-energy ions for applications in modern optics

    CERN Document Server

    Kennedy, M

    1999-01-01

    realised by a process adaptation with UV-absorbing films. A further focal point are antireflective coatings on alkali halides optics for high-power CO sub 2 -lasers. Ion assisted deposition of NaF-films at extremely low ion energies (E sub i sub o sub n approx 5 eV) qualifies antireflective coatings with minimal absorption (alpha approx 1.5 cm sup - sup 1), high short-pulse damage threshold (50%-LIDT approx 60J/cm sup 2) and improved degradational stability. Main objective of this work is the development of ion assisted deposition processes without additional substrate heating for applications in precision and laser optics. New low-energy ion sources with ion energies below 100 eV were employed for the research work. Starting point of the process development are basic investigations on the ion assisted evaporation of fluoride and oxide thin film materials. The optimisation of the coating processes is primary done with the help of optical characterisation methods (spectral photometry, laser calorimetry, measur...

  18. Ion-assisted deposition of moisture-stable hafnium oxide films for ultraviolet applications

    International Nuclear Information System (INIS)

    A design-of-experiments statistical approach was taken to determine the optimum ion gun operating parameters for the deposition of moisture-stable, low-absorbing hafnium oxide films by ion-assisted electron-beam evaporation. Factors identified as affecting the quality of hafnia films were chamber pressure, deposition rate, ion gun source gas composition, and ion gun current. Both oxygen and argon were used as source gases. High and low levels of the factors were chosen on the basis of our experience with the operating range of the system, and we made a series of 24 runs with all possible combinations of these factors. From a statistical analysis of the data, we find that the best films are obtained with a 1:1 mixture of argon and oxygen, 3-3.5 x 10-4 Torr chamber pressure, 0.3-nm/s deposition rate, and 0.5-A ion gun current. X-ray diffraction measurements show that the ion-assisted films exhibit a partial monoclinic crystalline structure, whereas the unassisted films are amorphous

  19. Ion-assisted deposition of moisture-stable hafnium oxide films for ultraviolet applications

    Science.gov (United States)

    Jensen, Traci R.; Warren, John; Johnson,, Robert L., Jr.

    2002-06-01

    A design-of-experiments statistical approach was taken to determine the optimum ion gun operating parameters for the deposition of moisture-stable, low-absorbing hafnium oxide films by ion-assisted electron-beam evaporation. Factors identified as affecting the quality of hafnia films were chamber pressure, deposition rate, ion gun source gas composition, and ion gun current. Both oxygen and argon were used as source gases. High and low levels of the factors were chosen on the basis of our experience with the operating range of the system, and we made a series of 24 runs with all possible combinations of these factors. From a statistical analysis of the data, we find that the best films are obtained with a 1:1 mixture of argon and oxygen, 3-3.5 x 10-4 Torr chamber pressure, 0.3-nm/s deposition rate, and 0.5-A ion gun current. X-ray diffraction measurements show that the ion-assisted films exhibit a partial monoclinic crystalline structure, whereas the unassisted films are amorphous.

  20. Scalable route to CH3NH3PbI3 perovskite thin films by aerosol assisted chemical vapour deposition

    OpenAIRE

    Bhachu, D. S.; Scanlon, D. O.; Saban, E. J.; Bronstein, H.; Parkin, I. P.; Carmalt, C. J.; Palgrave, R. G.

    2015-01-01

    Methyl-ammonium lead iodide is the archetypal perovskite solar cell material. Phase pure, compositionally uniform methyl-ammonium lead iodide thin films on large glass substrates were deposited using ambient pressure aerosol assisted chemical vapour deposition. This opens up a route to efficient scale up of hybrid perovskite film growth towards industrial deployment.

  1. Functionalized porphyrin conjugate thin films deposited by matrix assisted pulsed laser evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Iordache, S. [University of Bucharest, 3Nano-SAE Research Center, PO Box MG-38, Bucharest-Magurele (Romania); Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Popescu, A.C.; Popescu, C.E.; Dorcioman, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Ciucu, A.A. [University of Bucharest, Faculty of Chemistry, Bucharest (Romania); Balan, A.; Stamatin, I. [University of Bucharest, 3Nano-SAE Research Center, PO Box MG-38, Bucharest-Magurele (Romania); Fagadar-Cosma, E. [Institute of Chemistry Timisoara of Romanian Academy, M. Viteazul Ave. 24, 300223-Timisoara (Romania); Chrisey, D.B. [Tulane University, Departments of Physics and Biomedical Engineering, New Orleans, LA 70118 (United States)

    2013-08-01

    We report on the deposition of nanostructured porphyrin-base, 5(4-carboxyphenyl)-10,15,20-tris(4-phenoxyphenyl)-porphyrin thin films by matrix assisted pulsed laser evaporation onto silicon substrates with screen-printed electrodes. AFM investigations have shown that at 400 mJ/cm{sup 2} fluence a topographical transition takes place from the platelet-like stacking porphyrin-based nanostructures in a perpendicular arrangement to a quasi-parallel one both relative to the substrate surface. Raman spectroscopy has shown that the chemical structure of the deposited thin films is preserved for fluences within the range of 200–300 mJ/cm{sup 2}. Cyclic voltammograms have demonstrated that the free porphyrin is appropriate as a single mediator for glucose in a specific case of screen-printed electrodes, suggesting potential for designing a new class of biosensors.

  2. Continuous Microreactor-Assisted Solution Deposition for Scalable Production of CdS Films

    Energy Technology Data Exchange (ETDEWEB)

    Ramprasad, Sudhir; Su, Yu-Wei; Chang, Chih-Hung; Paul, Brian; Palo, Daniel R.

    2013-06-13

    Solution deposition offers an attractive, low temperature option in the cost effective production of thin film solar cells. Continuous microreactor-assisted solution deposition (MASD) was used to produce nanocrystalline cadmium sulfide (CdS) films on fluorine doped tin oxide (FTO) coated glass substrates with excellent uniformity. We report a novel liquid coating technique using a ceramic rod to efficiently and uniformly apply reactive solution to large substrates (152 mm × 152 mm). This technique represents an inexpensive approach to utilize the MASD on the substrate for uniform growth of CdS films. Nano-crystalline CdS films have been produced from liquid phase at ~90°C, with average thicknesses of 70 nm to 230 nm and with a 5 to 12% thickness variation. The CdS films produced were characterized by UV-Vis spectroscopy, transmission electron microscopy, and X-Ray diffraction to demonstrate their suitability to thin-film solar technology.

  3. Electrochemically assisted deposition of strontium modified magnesium phosphate on titanium surfaces.

    Science.gov (United States)

    Meininger, M; Wolf-Brandstetter, C; Zerweck, J; Wenninger, F; Gbureck, U; Groll, J; Moseke, C

    2016-10-01

    Electrochemically assisted deposition was utilized to produce ceramic coatings on the basis of magnesium ammonium phosphate (struvite) on corundum-blasted titanium surfaces. By the addition of defined concentrations of strontium nitrate to the coating electrolyte Sr(2+) ions were successfully incorporated into the struvite matrix. By variation of deposition parameters it was possible to fabricate coatings with different kinetics of Sr(2+) into physiological media, whereas the release of therapeutically relevant strontium doses could be sustained over several weeks. Morphological and crystallographic examinations of the immersed coatings revealed that the degradation of struvite and the release of Sr(2+) ions were accompanied by a transformation of the coating to a calcium phosphate based phase similar to low-crystalline hydroxyapatite. These findings showed that strontium doped struvite coatings may provide a promising degradable coating system for the local application of strontium or other biologically active metal ions in the implant-bone interface. PMID:27287100

  4. Biomolecular papain thin films grown by matrix assisted and conventional pulsed laser deposition: A comparative study

    Science.gov (United States)

    György, E.; Pérez del Pino, A.; Sauthier, G.; Figueras, A.

    2009-12-01

    Biomolecular papain thin films were grown both by matrix assisted pulsed laser evaporation (MAPLE) and conventional pulsed laser deposition (PLD) techniques with the aid of an UV KrF∗ (λ =248 nm, τFWHM≅20 ns) excimer laser source. For the MAPLE experiments the targets submitted to laser radiation consisted on frozen composites obtained by dissolving the biomaterial powder in distilled water at 10 wt % concentration. Conventional pressed biomaterial powder targets were used in the PLD experiments. The surface morphology of the obtained thin films was studied by atomic force microscopy and their structure and composition were investigated by Fourier transform infrared spectroscopy. The possible physical mechanisms implied in the ablation processes of the two techniques, under comparable experimental conditions were identified. The results showed that the growth mode, surface morphology as well as structure of the deposited biomaterial thin films are determined both by the incident laser fluence value as well as target preparation procedure.

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

    Institute of Scientific and Technical Information of China (English)

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

    2006-01-01

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

  6. Electron behaviour in CH4/H2 gas mixture in electron-assisted chemical vapour deposition

    Institute of Scientific and Technical Information of China (English)

    Dong Li-Fang; Ma Bo-Qin; Wang Zhi-Jun

    2004-01-01

    The behaviour of electrons in CH4/H2 gas mixture in electron-assisted chemical vapour deposition of diamond is investigated using Monte Carlo simulation. The electron drift velocity in gas mixture is obtained over a wide range of E/P (the ratio of the electric field to gas pressure) from 1500 to 300000 (V/m kPa-1). The electron energy distribution and average energy under different gas pressure (0.1-20kPa) and CH4 concentration (0.5%-10.0%) are calculated. Their effects on the diamond growth are also discussed. It is believed that these results will be helpful to the selection of optimum experimental conditions for high quality diamond film deposition.

  7. High fluence deposition of polyethylene glycol films at 1064 nm by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Kingshott, P.;

    2007-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) has been applied for deposition of thin polyethylene glycol (PEG) films with infrared laser light at 1064 nm. We have irradiated frozen targets (of 1 wt.% PEG dissolved in water) and measured the deposition rate in situ with a quartz crystal 2...... microbalance. The laser fluence needed to produce PEG films turned out to be unexpectedly high with a threshold of 9 J/cm(2) and the deposition rate was much lower than that with laser light at 355 nm. Results from matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI...

  8. Self-heating technique of metallic substrate for reel-to-reel and double-sided deposition of YBa{sub 2}Cu{sub 3}O{sub 7-δ} films

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fei; Zhao, Ruipeng; Xue, Yan; He, Yuanying; Zhang, Pan; Tao, Bowan; Xiong, Jie; Li, Yanrong [University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Film and Integrated Devices, Chengdu (China); Wang, Hui [Chinese Academy of Sciences, Applied Research Laboratory of Superconduction and New Material, Institute of Electrical Engineering, Beijing (China)

    2016-02-15

    A new, simple, and highly efficient heating technology for metal tape substrates is proposed and applied to reel-to-reel and double-sided film deposition. In this technology, direct electrical current (I{sub DC}) is conducted into the metal layer of oxide-buffered metal substrate to induce heat. Different substrate surface temperatures were achieved by varying I{sub DC} from 22 to 25 A. At these temperatures, a series of 1-μm-thick and 5-cm-long YBa{sub 2}Cu{sub 3}O{sub 7-δ} (YBCO) films were fabricated on ion-beam-assisted deposition (IBAD) templates through metal organic chemical vapor deposition. X-ray diffraction analysis on the samples revealed that the YBCO film changed its growth mode from mixed a-axis and c-axis to purely c-axis with increasing I{sub DC}. The optimal out-of-plane and in-plane texture reached ∝1.4 and 3.5 , respectively. A 30-m-long and 500-nm-thick single-sided YBCO-coated conductor was also prepared through reel-to-reel deposition using the proposed heating method. The fabricated conductor presented homogeneous crystallization and texture and exhibited a critical current density at self-field and 77 K (J{sub c} {sub 77K,} {sub 0T}) of 2.8-3.2 MA/cm{sup 2}. Moreover, 500-nm-thick YBCO films were fabricated simultaneously on both sides of the double-sided IBAD template. The two sides of films demonstrated uniform texture and J{sub c} {sub 77K,} {sub 0T} of 3.2 MA/cm{sup 2}. Results demonstrated that the proposed substrate heating technology can be used for reel-to-reel and double-sided deposition of YBCO-coated conductors. (orig.)

  9. Fabrication and characterization of kesterite Cu2ZnSnS4 thin films deposited by electrostatic spray assisted vapour deposition method

    OpenAIRE

    J.P. Liu; Choy, Kwang-Leong; Placidi, M.; J. López-García; Saucedo, Edgardo; Colombara, Diego; Robert, Erika

    2014-01-01

    Most of the high efficiency kesterite solar cells are fabricated by vacuum or hydrazine-based solution methods which have drawbacks, such as high cost, high toxicity or explosivity. In our contribution, an alternative non-vacuum and environmental friendly deposition technology called electrostatic spray assisted vapour deposition (ESAVD) has been used for the cost-effective growth of Cu2ZnSnS4 (CZTS) thin films with well controlled structure and composition. CZTS films have been characterized...

  10. Graphene-assisted growth of high-quality AlN by metalorganic chemical vapor deposition

    Science.gov (United States)

    Zeng, Qing; Chen, Zhaolong; Zhao, Yun; Wei, Tongbo; Chen, Xiang; Zhang, Yun; Yuan, Guodong; Li, Jinmin

    2016-08-01

    High-quality AlN films were directly grown on graphene/sapphire substrates by metalorganic chemical vapor deposition (MOCVD). The graphene layers were directly grown on sapphire by atmospheric-pressure chemical vapor deposition (APCVD), a low-cost catalyst-free method. We analyzed the influence of the graphene layer on the nucleation of AlN at the initial stage of growth and found that sparse AlN grains on graphene grew and formed a continuous film via lateral coalescence. Graphene-assisted AlN films are smooth and continuous, and the full width at half maximum (FWHM) values for (0002) and (10\\bar{1}2) reflections are 360 and 622.2 arcsec, which are lower than that of the film directly grown on sapphire. The high-resolution TEM images near the AlN/sapphire interface for graphene-assisted AlN films clearly show the presence of graphene, which kept its original morphology after the 1200 °C growth of AlN.

  11. Surfactant-assisted electrochemical deposition of {alpha}-cobalt hydroxide for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Ting [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Jiang, Hao; Ma, Jan [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Temasek Laboratories, Nanyang Technological University, Singapore 637553 (Singapore)

    2011-01-15

    A N-methylpyrrolidone (NMP) assisted electrochemical deposition route has been developed to realize the synthesis of a dense {alpha}-Co(OH){sub 2} layered structure, which is composed of nanosheets, each with a thickness of 10 nm. The capacitive characteristics of the as-obtained {alpha}-Co(OH){sub 2} are investigated by means of cyclic voltammetry (CV), charge/discharge characterization, and electrochemical impedance spectroscopy (EIS), in 1 M KOH electrolyte. The results indicate that {alpha}-Co(OH){sub 2} prepared in the presence of 20 vol.% NMP has denser and thin layered structure which promotes an increased surface area and a shortened ion diffusion path. The as-prepared {alpha}-Co(OH){sub 2} shows better electrochemical performance with specific capacitance of 651 F g{sup -1} in a potential range of -0.1 to 0.45 V. These findings suggest that the surfactant-assisted electrochemical deposition is a promising process for building densely packed material systems with enhanced properties, for application in supercapacitors. (author)

  12. Surfactant-assisted electrochemical deposition of α-cobalt hydroxide for supercapacitors

    Science.gov (United States)

    Zhao, Ting; Jiang, Hao; Ma, Jan

    A N-methylpyrrolidone (NMP) assisted electrochemical deposition route has been developed to realize the synthesis of a dense α-Co(OH) 2 layered structure, which is composed of nanosheets, each with a thickness of 10 nm. The capacitive characteristics of the as-obtained α-Co(OH) 2 are investigated by means of cyclic voltammetry (CV), charge/discharge characterization, and electrochemical impedance spectroscopy (EIS), in 1 M KOH electrolyte. The results indicate that α-Co(OH) 2 prepared in the presence of 20 vol.% NMP has denser and thin layered structure which promotes an increased surface area and a shortened ion diffusion path. The as-prepared α-Co(OH) 2 shows better electrochemical performance with specific capacitance of 651 F g -1 in a potential range of -0.1 to 0.45 V. These findings suggest that the surfactant-assisted electrochemical deposition is a promising process for building densely packed material systems with enhanced properties, for application in supercapacitors.

  13. High-speed deposition of titanium carbide coatings by laser-assisted metal–organic CVD

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yansheng [Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Tu, Rong, E-mail: turong@whut.edu.cn [State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Goto, Takashi [Institute for Materials Research, Tohoku University, Aoba-ku, 2-1-1 Katahira, Sendai 980-8577 (Japan)

    2013-08-01

    Graphical abstract: - Highlights: • A semiconductor laser was first used to prepare wide-area LCVD-TiC{sub x} coatings. • The effect of laser power for the deposition of TiC{sub x} coatings was discussed. • TiC{sub x} coatings showed a columnar cross section and a dense surface texture. • TiC{sub x} coatings had a 1–4 order lower laser density than those of previous reports. • This study gives the possibility of LCVD applying on the preparation of TiC{sub x} coating. - Abstract: A semiconductor laser-assisted chemical vapor deposition (LCVD) of titanium carbide (TiC{sub x}) coatings on Al{sub 2}O{sub 3} substrate using tetrakis (diethylamido) titanium (TDEAT) and C{sub 2}H{sub 2} as source materials were investigated. The influences of laser power (P{sub L}) and pre-heating temperature (T{sub pre}) on the microstructure and deposition rate of TiC{sub x} coatings were examined. Single phase of TiC{sub x} coatings were obtained at P{sub L} = 100–200 W. TiC{sub x} coatings had a cauliflower-like surface and columnar cross section. TiC{sub x} coatings in the present study had the highest R{sub dep} (54 μm/h) at a relative low T{sub dep} than those of conventional CVD-TiC{sub x} coatings. The highest volume deposition rate (V{sub dep}) of TiC{sub x} coatings was about 4.7 × 10{sup −12} m{sup 3} s{sup −1}, which had 3–10{sup 5} times larger deposition area and 1–4 order lower laser density than those of previous LCVD using CO{sub 2}, Nd:YAG and argon ion laser.

  14. The Formation of Nanocrystalline Diamond Coating on WC Deposited by Microwave Assisted Plasma CVD

    Science.gov (United States)

    Toff, M. R. M.; Hamzah, E.; Purniawan, A.

    2010-03-01

    Diamond is one form of carbon structure. The extreme hardness and high chemical resistant of diamond coatings determined that many works on this area relate to coated materials for tribological applications in biomedicine, as mechanical seals or cutting tools for hard machining operations. In the work, nanocrystalline diamond (NCD) coated tungsten carbide (WC) have been deposited by microwave assisted plasma chemical vapor deposition (MAPCVD) from CH4/H2 mixtures. Morphology of NCD was investigated by using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The quality of NCD is defined as ratio between diamond and non diamond and also full width at half maximum (FWHM) was determined using Raman spectra. The result found that the NCD structure can be deposited on WC surface using CH4/H2 gas mixture with grain size ˜20 nm to 100 nm. Increase %CH4 concentration due to increase the nucleation of NCD whereas decrease the quality of diamond. Based on Raman spectra, the quality of NCD is in the range ˜98.82-99.01% and 99.56-99.75% for NCD and microcrystalline (MCD), respectively. In addition, FWHM of NCD is high than MCD in the range of 8.664-62.24 cm-1 and 4.24-5.05 cm-1 for NCD and MCD respectively that indicate the crystallineity of NCD is smaller than MCD.

  15. Nanocomposite Coatings Codeposited with Nanoparticles Using Aerosol-Assisted Chemical Vapour Deposition

    Directory of Open Access Journals (Sweden)

    Xianghui Hou

    2013-01-01

    Full Text Available Incorporating nanoscale materials into suitable matrices is an effective route to produce nanocomposites with unique properties for practical applications. Due to the flexibility in precursor atomization and delivery, aerosol-assisted chemical vapour deposition (AACVD process is a promising way to synthesize desired nanocomposite coatings incorporating with preformed nanoscale materials. The presence of nanoscale materials in AACVD process would significantly influence deposition mechanism and thus affect microstructure and properties of the nanocomposites. In the present work, inorganic fullerene-like tungsten disulfide (IF-WS2 has been codeposited with Cr2O3 coatings using AACVD. In order to understand the codeposition process for the nanocomposite coatings, chemical reactions of the precursor and the deposition mechanism have been studied. The correlation between microstructure of the nanocomposite coatings and the codeposition mechanism in the AACVD process has been investigated. The heterogeneous reaction on the surface of IF-WS2 nanoparticles, before reaching the substrate surface, is the key feature of the codeposition in the AACVD process. The agglomeration of nanoparticles in the nanocomposite coatings is also discussed.

  16. Low-Temperature Plasma-Assisted Atomic Layer Deposition of Silicon Nitride Moisture Permeation Barrier Layers.

    Science.gov (United States)

    Andringa, Anne-Marije; Perrotta, Alberto; de Peuter, Koen; Knoops, Harm C M; Kessels, Wilhelmus M M; Creatore, Mariadriana

    2015-10-14

    Encapsulation of organic (opto-)electronic devices, such as organic light-emitting diodes (OLEDs), photovoltaic cells, and field-effect transistors, is required to minimize device degradation induced by moisture and oxygen ingress. SiNx moisture permeation barriers have been fabricated using a very recently developed low-temperature plasma-assisted atomic layer deposition (ALD) approach, consisting of half-reactions of the substrate with the precursor SiH2(NH(t)Bu)2 and with N2-fed plasma. The deposited films have been characterized in terms of their refractive index and chemical composition by spectroscopic ellipsometry (SE), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR). The SiNx thin-film refractive index ranges from 1.80 to 1.90 for films deposited at 80 °C up to 200 °C, respectively, and the C, O, and H impurity levels decrease when the deposition temperature increases. The relative open porosity content of the layers has been studied by means of multisolvent ellipsometric porosimetry (EP), adopting three solvents with different kinetic diameters: water (∼0.3 nm), ethanol (∼0.4 nm), and toluene (∼0.6 nm). Irrespective of the deposition temperature, and hence the impurity content in the SiNx films, no uptake of any adsorptive has been observed, pointing to the absence of open pores larger than 0.3 nm in diameter. Instead, multilayer development has been observed, leading to type II isotherms that, according to the IUPAC classification, are characteristic of nonporous layers. The calcium test has been performed in a climate chamber at 20 °C and 50% relative humidity to determine the intrinsic water vapor transmission rate (WVTR) of SiNx barriers deposited at 120 °C. Intrinsic WVTR values in the range of 10(-6) g/m2/day indicate excellent barrier properties for ALD SiNx layers as thin as 10 nm, competing with that of state-of-the-art plasma-enhanced chemical vapor-deposited SiNx layers of a few hundred

  17. Microwave engineering of plasma-assisted CVD reactors for diamond deposition

    Science.gov (United States)

    Silva, F.; Hassouni, K.; Bonnin, X.; Gicquel, A.

    2009-09-01

    The unique properties of CVD diamond make it a compelling choice for high power electronics. In order to achieve industrial use of CVD diamond, one must simultaneously obtain an excellent control of the film purity, very low defect content and a sufficiently rapid growth rate. Currently, only microwave plasma-assisted chemical vapour deposition (MPACVD) processes making use of resonant cavity systems provide enough atomic hydrogen to satisfy these requirements. We show in this paper that the use of high microwave power density (MWPD) plasmas is necessary to promote atomic hydrogen concentrations that are high enough to ensure the deposition of high purity diamond films at large growth rates. Moreover, the deposition of homogeneous films on large surfaces calls for the production of plasma with appropriate shapes and large volumes. The production of such plasmas needs generating a fairly high electric field over extended regions and requires a careful design of the MW coupling system, especially the cavity. As far as MW coupling efficiency is concerned, the presence of a plasma load represents a mismatching perturbation to the cavity. This perturbation is especially important at high MWPD where the reflected fraction of the input power may be quite high. This mismatch can lead to a pronounced heating of the reactor walls. It must therefore be taken into account from the very beginning of the reactor design. This requires the implementation of plasma modelling tools coupled to detailed electromagnetic simulations. This is discussed in section 3. We also briefly discuss the operating principles of the main commercial plasma reactors before introducing the reactor design methodology we have developed. Modelling results for a new generation of reactors developed at LIMHP, working at very high power density, will be presented. Lastly, we show that scaling up this type of reactor to lower frequencies (915 MHz) can result in high density plasmas allowing for fast and

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-05-01

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

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

    International Nuclear Information System (INIS)

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

  20. Quarterly Report: Microchannel-Assisted Nanomaterial Deposition Technology for Photovoltaic Material Production

    Energy Technology Data Exchange (ETDEWEB)

    Palo, Daniel R.

    2011-04-26

    Quarterly report to ITP for Nanomanufacturing program. Report covers FY11 Q2. The primary objective of this project is to develop a nanomanufacturing process which will reduce the manufacturing energy, environmental discharge, and production cost associated with current nano-scale thin-film photovoltaic (PV) manufacturing approaches. The secondary objective is to use a derivative of this nanomanufacturing process to enable greener, more efficient manufacturing of higher efficiency quantum dot-based photovoltaic cells now under development. The work is to develop and demonstrate a scalable (pilot) microreactor-assisted nanomaterial processing platform for the production, purification, functionalization, and solution deposition of nanomaterials for photovoltaic applications. The high level task duration is shown. Phase I consists of a pilot platform for Gen II PV films along with parallel efforts aimed at Gen III PV quantum dot materials. Status of each task is described.

  1. Synthesis of conductive semi-transparent silver films deposited by a Pneumatically-Assisted Ultrasonic Spray Pyrolysis Technique

    Energy Technology Data Exchange (ETDEWEB)

    Zaleta-Alejandre, E.; Balderas-Xicoténcatl, R. [Centro de Investigación y de Estudios Avanzados-IPN, Departamento de Física, , Apdo. Postal 14-470, Del, Gustavo A. Madero, C.P. 07000, México, D.F. (Mexico); Arrieta, M.L. Pérez [Universidad Autónoma de Zacatecas, Unidad Académica de Física, Calzada Solidaridad esq. Paseo, La Bufa s/n, C.P. 98060, Zacatecas, México (Mexico); Meza-Rocha, A.N.; Rivera-Álvarez, Z. [Centro de Investigación y de Estudios Avanzados-IPN, Departamento de Física, , Apdo. Postal 14-470, Del, Gustavo A. Madero, C.P. 07000, México, D.F. (Mexico); Falcony, C., E-mail: cfalcony@fis.cinvestav.mx [Centro de Investigación y de Estudios Avanzados-IPN, Departamento de Física, , Apdo. Postal 14-470, Del, Gustavo A. Madero, C.P. 07000, México, D.F. (Mexico)

    2013-10-01

    Highlights: • We deposited metallic silver films without post-deposition annealing. • The spray pyrolysis technique is of low cost and scalable for industrial applications. • We obtained deposition rate of 60 nm min{sup −1} at 300 °C. • The average resistivity was 1E−7 Ω m. • Semi-transparent silver films were obtained at 350 °C and deposition time of 45 s. -- Abstract: The synthesis and characterization of nanostructured silver films deposited on corning glass by a deposition technique called Pneumatically-Assisted Ultrasonic Spray Pyrolysis are reported. Silver nitrate and triethanolamine were used as silver precursor and reducer agent, respectively. The substrate temperatures during deposition were in the range of 300–450 °C and the deposition times from 30 to 240 s. The deposited films are polycrystalline with cubic face-centered structure, and crystalline grain size less than 30 nm. Deposition rates up to 600 Å min{sup −1} were obtained at substrate temperature as low as 300 °C. The electrical, optical, and morphological properties of these films are also reported. Semi-transparent conductive silver films were obtained at 350 °C with a deposition time of 45 s.

  2. Plasma-Assisted Laser Deposition of High T(c) Oxide Superconducting Thin Films.

    Science.gov (United States)

    Witanachchi, Sarath

    1990-01-01

    Since the discovery of the high T_ {rm c} oxide superconductor YBa _2Cu_3O _7 a great deal of attention has been given to the fabrication of superconducting thin films of this material. Thin films of the new superconductor have an immense importance in scientific research, such as microwave, infrared and critical current studies, and also in applications, such as Josephson junction based digital computer circuits, SQUID (Superconducting Quantum Interference Devices), transmission lines, and interconnectors. Integration of these films with semiconductors and multilayer capabilities are important for future practical uses. For most of these applications, a low temperature in-situ fabrication process is designed to obtain smooth surfaces and sharp interfaces. Less than 500^circC growth temperatures would be compatible with the existing semiconductor technology. At the beginning of this research project, the lowest deposition temperature reported for the fabrication of in-situ superconducting films was about 650^circC. Our goal was to develop a technique that would enable us to fabricate in-situ high T_{ rm c} superconducting films at a substrate temperature lower than 650^circC. By incorporating a weak oxygen plasma in the laser evaporation zone, we have been able to develop a novel plasma assisted laser deposition (PLD) technique to grow YBaCuO films that are superconducting in the as-deposited state. Using this technique, good quality superconducting films with mirror -like surfaces have been grown at substrate temperatures as low as 500^circC. YBaCuO films were deposited on single crystal substrates, SrTiO_3, ZrO _2, MgO, sapphire and Si, and also on flexible stainless steel substrates. Films deposited on SrTiO _3 at 500^circC showed a critical temperature of 86K and a critical current of 10^5 A/cm^2 at 80K and 5 times 10^6 A/cm^2 at 4.3K. The possibility of improving the superconducting properties of the films deposited on sapphire, Si, and stainless steel by

  3. Effects of precursor evaporation temperature on the properties of the yttrium oxide thin films deposited by microwave electron cyclotron resonance plasma assisted metal organic chemical vapor deposition

    International Nuclear Information System (INIS)

    Yttrium oxide thin films are deposited using indigenously developed metal organic precursor (2,2,6,6-tetra methyl-3,5-hepitane dionate) yttrium, commonly known as Y(thd)3 (synthesized by ultrasound method). Microwave electron cyclotron resonance plasma assisted metal organic chemical vapor deposition process was used for these depositions. Depositions were carried out at a substrate temperature of 350 oC with argon to oxygen gas flow rates fixed to 1 sccm and 10 sccm respectively throughout the experiments. The precursor evaporation temperature (precursor temperature) was varied over a range of 170-275 oC keeping all other parameters constant. The deposited coatings are characterized by X-ray photoelectron spectroscopy, glancing angle X-ray diffraction and infrared spectroscopy. Thickness and refractive index of the coatings are measured by the spectroscopic ellipsometry. Hardness and elastic modulus of the films are measured by load depth sensing nanoindentation technique. C-Y2O3 phase is deposited at lower precursor temperature (170 oC). At higher temperature (220 oC) cubic yttrium oxide is deposited with yttrium hydroxide carbonate as a minor phase. When the temperature of the precursor increased (275 oC) further, hexagonal Y2O3 with some multiphase structure including body centered cubic yttria and yttrium silicate is observed in the deposited film. The properties of the films drastically change with these structural transitions. These changes in the film properties are correlated here with the precursor evaporation characteristics obtained at low pressures.

  4. Surface reaction mechanisms during ozone and oxygen plasma assisted atomic layer deposition of aluminum oxide.

    Science.gov (United States)

    Rai, Vikrant R; Vandalon, Vincent; Agarwal, Sumit

    2010-09-01

    We have elucidated the reaction mechanism and the role of the reactive intermediates in the atomic layer deposition (ALD) of aluminum oxide from trimethyl aluminum in conjunction with O(3) and an O(2) plasma. In situ attenuated total reflection Fourier transform infrared spectroscopy data show that both -OH groups and carbonates are formed on the surface during the oxidation cycle. These carbonates, once formed on the surface, are stable to prolonged O(3) exposure in the same cycle. However, in the case of plasma-assisted ALD, the carbonates decompose upon prolonged O(2) plasma exposure via a series reaction kinetics of the type, A (CH(3)) --> B (carbonates) --> C (Al(2)O(3)). The ratio of -OH groups to carbonates on the surface strongly depends on the oxidizing agent, and also the duration of the oxidation cycle in plasma-assisted ALD. However, in both O(3) and O(2) plasma cycles, carbonates are a small fraction of the total number of reactive sites compared to the hydroxyl groups.

  5. Chemical vapor deposition graphene transfer process to a polymeric substrate assisted by a spin coater

    Science.gov (United States)

    Kessler, Felipe; da Rocha, Caique O. C.; Medeiros, Gabriela S.; Fechine, Guilhermino J. M.

    2016-03-01

    A new method to transfer chemical vapor deposition graphene to polymeric substrates is demonstrated here, it is called direct dry transfer assisted by a spin coater (DDT-SC). Compared to the conventional method DDT, the improvement of the contact between graphene-polymer due to a very thin polymeric film deposited by spin coater before the transfer process prevented air bubbles and/or moisture and avoided molecular expansion on the graphene-polymer interface. An acrylonitrile-butadiene-styrene copolymer, a high impact polystyrene, polybutadiene adipate-co-terephthalate, polylactide acid, and a styrene-butadiene-styrene copolymer are the polymers used for the transfers since they did not work very well by using the DDT process. Raman spectroscopy and optical microscopy were used to identify, to quantify, and to qualify graphene transferred to the polymer substrates. The quantity of graphene transferred was substantially increased for all polymers by using the DDT-SC method when compared with the DDT standard method. After the transfer, the intensity of the D band remained low, indicating low defect density and good quality of the transfer. The DDT-SC transfer process expands the number of graphene applications since the polymer substrate candidates are increased.

  6. Hybrid chemical vapour and nanoceramic aerosol assisted deposition for multifunctional nanocomposite thin films

    Energy Technology Data Exchange (ETDEWEB)

    Warwick, Michael E.A.; Dunnill, Charles W.; Goodall, Josie; Darr, Jawwad A.; Binions, Russell, E-mail: uccarbi@ucl.ac.uk

    2011-07-01

    Hybrid atmospheric pressure chemical vapour and aerosol assisted deposition via the reaction of vanadium acetylacetonate and a suspension of preformed titanium dioxide or cerium dioxide nanoparticles, led to the production of vanadium dioxide nanocomposite thin films on glass substrates. The preformed nanoparticle oxides used for the aerosol were synthesised using a continuous hydrothermal flow synthesis route involving the rapid reaction of a metal salt solution with a flow of supercritical water in a flow reactor. Multifunctional nanocomposite thin films from the hybrid deposition process were characterised using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The functional properties of the films were evaluated using variable temperature optical measurements to assess thermochromic behaviour and methylene blue photodecolourisation experiments to assess photocatalytic activity. The tests show that the films are multifunctional in that they are thermochromic (having a large change in infra-red reflectivity upon exceeding the thermochromic transition temperature) and have significant photocatalytic activity under irradiation with 254 nm light.

  7. Direct Fabrication of Carbon Nanotubes STM Tips by Liquid Catalyst-Assisted Microwave Plasma-Enhanced Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    Fa-Kuei Tung

    2009-01-01

    Full Text Available Direct and facile method to make carbon nanotube (CNT tips for scanning tunneling microscopy (STM is presented. Cobalt (Co particles, as catalysts, are electrochemically deposited on the apex of tungsten (W STM tip for CNT growth. It is found that the quantity of Co particles is well controlled by applied DC voltage, concentration of catalyst solution, and deposition time. Using optimum growth condition, CNTs are successfully synthesized on the tip apex by catalyst-assisted microwave-enhanced chemical vapor deposition (CA-MPECVD. A HOPG surface is clearly observed at an atomic scale using the present CNT-STM tip.

  8. Influence of travel speed on spray deposition uniformity from an air-assisted variable-rate sprayer

    Science.gov (United States)

    A newly developed LiDAR-guided air-assisted variable-rate sprayer for nursery and orchard applications was tested at various travel speeds to compare its spray deposition and coverage uniformity with constant-rate applications. Spray samplers, including nylon screens and water-sensitive papers (WSP)...

  9. Development of aerosol assisted chemical vapor deposition for thin film fabrication

    Science.gov (United States)

    Maulana, Dwindra Wilham; Marthatika, Dian; Panatarani, Camellia; Mindara, Jajat Yuda; Joni, I. Made

    2016-02-01

    Chemical vapor deposition (CVD) is widely used to grow a thin film applied in many industrial applications. This paper report the development of an aerosol assisted chemical vapor deposition (AACVD) which is one of the CVD methods. Newly developed AACVD system consists of a chamber of pyrex glass, two wire-heating elements placed to cover pyrex glass, a substrate holder, and an aerosol generator using an air brush sprayer. The temperature control system was developed to prevent condensation on the chamber walls. The control performances such as the overshoot and settling time were obtained from of the developed temperature controller. Wire-heating elements were controlled at certain setting value to heat the injected aerosol to form a thin film in the substrate. The performance of as-developed AACVD system tested to form a thin film where aerosol was sprayed into the chamber with a flow rate of 7 liters/minutes, and vary in temperatures and concentrations of precursor. The temperature control system have an overshoot around 25 °C from the desired set point temperature, very small temperature ripple 2 °C and a settling time of 20 minutes. As-developed AACVD successfully fabricated a ZnO thin film with thickness of below 1 µm. The performances of system on formation of thin films influenced by the generally controlled process such as values of setting temperature and concentration where the aerosol flow rate was fixed. Higher temperature was applied, the more uniform ZnO thin films were produced. In addition, temperature of the substrate also affected on surface roughness of the obtained films, while concentration of ZnO precursor determined the thickness of produce films. It is concluded that newly simple AACVD can be applied to produce a thin film.

  10. New ion-assisted filtered cathodic arc deposition (IFCAD) technology for producing advanced thin films on temperature-sensitive substrates

    Science.gov (United States)

    Fulton, Michael L.

    1999-10-01

    An innovative Ion-Assisted Filtered Cathodic Arc Deposition (IFCAD) system has been developed for low temperature production of thin-film coatings. The IFCAD system employs electro-magnetic and mechanical filtering techniques to remove unwanted macroparticles and neutral atoms from the plasma stream. Therefore, only ions within a defined energy range arrive at the substrate surface, depositing thin-films with excellent mechanical and optical properties. Ion- Assisted-Deposition is coupled with Filtered Cathodic Arc technology to enhance and modify the arc deposited thin- films. Using an advanced computer controlled plasma beam scanning system, high quality, large area, uniform IFCAD multi-layer film structures are attained. Amorphous Diamond- Like-Carbon films (up to 85% sp3 bonded carbon; and micro- hardness greater than 50 GPa) have been deposited in multi- layer thin-film combinations with other IFCAD source materials (such as: Al2O3) for optical and tribological applications. Rutile TiO2 (refractive index of 2.8 at 500 nm) has been deposited with this technology for advanced optical filter applications. The new IFCAD technology has been included in development programs, such as: plastic and glass lens coatings for optical systems; wear resistant coatings on various metal substrates, ultra smooth, durable, surface hydrophobic coatings for aircraft windows; EUV coatings for space instrumentation; transparent conductive coatings; and UV protective coatings for solar cell concentrator plastic Fresnel lens elements for space power.

  11. Influence of APS bias voltage on properties of HfO2 and SiO2 single layer deposited by plasma ion-assisted deposition

    Institute of Scientific and Technical Information of China (English)

    Meiping Zhu; Kui Yi; Zhengxiu Fan; Jianda Shao

    2011-01-01

    @@ HfO2 and SiO2 single layer is deposited on glass substrate with plasma ion assistance provided by Leybold advanced plasma source (APS). The deposition is performed with a bias voltage in the range of 70-130 V for HfO2, and 70-170 V for SiO2. Optical, structural, mechanical properties, as well as absorption and laser induced damage threshold at 1064 nm of HfO2 and SiO2 single layer deposited with the plasma ion assistance are systematically investigated. With the increase of APS bias voltage, coatings with higher refractive index, reduced surface roughness, and higher laser-induced damage threshold (LIDT) are obtained, and no significant change of the absorption at 1064 nm is observed. For HfO2, a bias voltage can be identified to achieve coatings without any stress. However, too-high bias voltage can cause the increase of surface roughness and stress, and decrease the LIDT. The bias voltage can be properly identified to achieve coatings with desired properties.%HfO2 and SiO2 single layer is deposited on glass substrate with plasma ion assistance provided by Leybold advanced plasma source (APS). The deposition is performed with a bias voltage in the range of 70-130 V for HfO2, and 70-170 V for SiO2. Optical, structural, mechanical properties, as well as absorption and laser induced damage threshold at 1064 nm of HfO2 and SiO2 single layer deposited with the plasma ion assistance are systematically investigated. With the increase of APS bias voltage, coatings with higher refractive index, reduced surface roughness, and higher laser-induced damage threshold (LIDT) are obtained, and no significant change of the absorption at 1064 nm is observed. For HfO2, a bias voltage can be identified to achieve coatings without any stress. However, too-high bias voltage can cause the increase of surface roughness and stress, and decrease the LIDT. The bias voltage can be properly identified to achieve coatings with desired properties.

  12. Platinum-assisted post deposition annealing of the n-Ge/Y2O3 interface

    Science.gov (United States)

    Zimmermann, C.; Bethge, O.; Lutzer, B.; Bertagnolli, E.

    2016-07-01

    The impact of annealing temperature and annealing duration on the interface properties of n-Ge/Y2O3/Pt MOS-capacitors is investigated employing an ultrathin catalytically acting Pt-layer. X-ray photoelectron spectroscopy analysis has been used to verify an enhanced growth of GeO2 and thermally stabilizing yttrium germanate at the n-Ge/Y2O3 interface induced by an oxygen post deposition annealing (PDA). Especially at 500 °C and 550 °C high quality Ge/Y2O3 interfaces have been achieved resulting in very low interface trap density of 7.41*1010 eV-1 cm-2. It is shown that either a short oxygen annealing at higher temperatures (550 °C) or a long time annealing at lower temperatures (450 °C) are appropriate to realize low interface trap density (D it). It turns out that a Pt-assisted PDA in combination with a final PMA are needed to reduce hysteresis width significantly and to bring flat band voltages toward ideal values.

  13. Ultralight boron nitride aerogels via template-assisted chemical vapor deposition

    Science.gov (United States)

    Song, Yangxi; Li, Bin; Yang, Siwei; Ding, Guqiao; Zhang, Changrui; Xie, Xiaoming

    2015-05-01

    Boron nitride (BN) aerogels are porous materials with a continuous three-dimensional network structure. They are attracting increasing attention for a wide range of applications. Here, we report the template-assisted synthesis of BN aerogels by catalyst-free, low-pressure chemical vapor deposition on graphene-carbon nanotube composite aerogels using borazine as the B and N sources with a relatively low temperature of 900 °C. The three-dimensional structure of the BN aerogels was achieved through the structural design of carbon aerogel templates. The BN aerogels have an ultrahigh specific surface area, ultralow density, excellent oil absorbing ability, and high temperature oxidation resistance. The specific surface area of BN aerogels can reach up to 1051 m2 g-1, 2-3 times larger than the reported BN aerogels. The mass density can be as low as 0.6 mg cm-3, much lower than that of air. The BN aerogels exhibit high hydrophobic properties and can absorb up to 160 times their weight in oil. This is much higher than porous BN nanosheets reported previously. The BN aerogels can be restored for reuse after oil absorption simply by burning them in air. This is because of their high temperature oxidation resistance and suggests broad utility as water treatment tools.

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

    International Nuclear Information System (INIS)

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

  15. Electron Cyclotron Resonance Plasma-Assisted Atomic Layer Deposition of Amorphous Al2O3 Thin Films

    International Nuclear Information System (INIS)

    Without extra heating, Al2O3 thin films were deposited on a hydrogen-terminated Si substrate etched in hydrofluoric acid by using a self-built electron cyclotron resonance (ECR) plasma-assisted atomic layer deposition (ALD) device with Al(CH3)3 (trimethylaluminum; TMA) and O2 used as precursor and oxidant, respectively. During the deposition process, Ar was introduced as a carrier and purging gas. The chemical composition and microstructure of the as-deposited Al2O3 films were characterized by using X-ray diffraction (XRD), an X-ray photoelectric spectroscope (XPS), a scanning electron microscope (SEM), an atomic force microscope (AFM) and a high-resolution transmission electron microscope (HRTEM). It achieved a growth rate of 0.24 nm/cycle, which is much higher than that deposited by thermal ALD. It was found that the smooth surface thin film was amorphous alumina, and an interfacial layer formed with a thickness of ca. 2 nm was observed between the Al2O3 film and substrate Si by HRTEM. We conclude that ECR plasma-assisted ALD can grow Al2O3 films with an excellent quality at a high growth rate at ambient temperature.

  16. Study on absorbance and laser damage threshold of HfO2 films prepared by ion-assisted reaction deposition

    Institute of Scientific and Technical Information of China (English)

    张大伟; 范树海; 高卫东; 贺洪波; 王英剑; 邵建达; 范正修; 孙浩杰

    2004-01-01

    Using a new kind of EH1000 ion source, hafnium dioxide (HfO2) films are deposited with different depo sition techniques and different conditions. The absorbance and the laser damage threshold of these films have been measured and studied. By comparing these characteristics, one can conclude that under right conditions, such as high partial pressure of oxygen and right kind of ion source, the ion-assisted reaction deposition can prepare HfO2 films with higher laser induced damage threshold.

  17. Nanoparticulate cerium dioxide and cerium dioxide-titanium dioxide composite thin films on glass by aerosol assisted chemical vapour deposition

    International Nuclear Information System (INIS)

    Two series of composite thin films were deposited on glass by aerosol assisted chemical vapour deposition (AACVD)-nanoparticulate cerium dioxide and nanoparticulate cerium dioxide embedded in a titanium dioxide matrix. The films were analysed by a range of techniques including UV-visible absorption spectroscopy, X-ray diffraction, scanning electron microscopy and energy dispersive analysis by X-rays. The AACVD prepared films showed the functional properties of photocatalysis and super-hydrophilicity. The CeO2 nanoparticle thin films displaying photocatalysis and photo-induced hydrophilicity almost comparable to that of anatase titania.

  18. Development of a high magnetic field assisted pulsed laser deposition system

    Science.gov (United States)

    Zhang, Kejun; Dai, Jianming; Wu, Wenbin; Zhang, Peng; Zuo, Xuzhong; Zhou, Shu; Zhu, Xuebin; Sheng, Zhigao; Liang, Changhao; Sun, Yuping

    2015-09-01

    A high magnetic field assisted pulsed laser deposition (HMF-PLD) system has been developed to in situ grow thin films in a high magnetic field up to 10 T. In this system, a specially designed PLD cylindrical vacuum chamber is horizontally located in the bore configuration of a superconducting magnet with a bore diameter of 200 mm. To adjust the focused pulsed laser into the target in such a narrow PLD vacuum chamber, an ingeniously built-in laser leading-in chamber is employed, including a laser mirror with a reflection angle of 65° and a damage threshold up to 3.4 J/cm2. A laser alignment system consisting of a built-in video-unit leading-in chamber and a low-energy alignment laser is applied to monitor and align the pulsed laser propagation in the PLD vacuum chamber. We have grown La0.7Sr0.3MnO3 (LSMO) thin films on (LaAlO3)0.3(Sr2AlTaO6)0.7 (001) [LSAT (001)] substrates by HMF-PLD. The results show that the nanostructures of the LSMO films can be tuned from an epitaxially continuous film structure without field to a vertically aligned nanorod structure with an applied high magnetic field above 5 T, and the dimension size of the nanorods can be tuned by the strength of the magnetic field. The associated magnetic anisotropy is found to be highly dependent on the nanorod structures. We show how the HMF-PLD provides an effective route toward tuning the nanostructures and the physical properties of functional thin films, giving it an important role in development of nanodevices and their application.

  19. Fabrication of three-dimensional scaffolds using precision extrusion deposition with an assisted cooling device

    Energy Technology Data Exchange (ETDEWEB)

    Hamid, Q; Snyder, J; Wang, C; Guceri, S; Sun, W [Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA (United States); Timmer, M; Hammer, J, E-mail: sunwei@drexel.edu [Advanced Technologies and Regenerative Medicine, Somerville, NJ (United States)

    2011-09-15

    In the field of biofabrication, tissue engineering and regenerative medicine, there are many methodologies to fabricate a building block (scaffold) which is unique to the target tissue or organ that facilitates cell growth, attachment, proliferation and/or differentiation. Currently, there are many techniques that fabricate three-dimensional scaffolds; however, there are advantages, limitations and specific tissue focuses of each fabrication technique. The focus of this initiative is to utilize an existing technique and expand the library of biomaterials which can be utilized to fabricate three-dimensional scaffolds rather than focusing on a new fabrication technique. An expanded library of biomaterials will enable the precision extrusion deposition (PED) device to construct three-dimensional scaffolds with enhanced biological, chemical and mechanical cues that will benefit tissue generation. Computer-aided motion and extrusion drive the PED to precisely fabricate micro-scaled scaffolds with biologically inspired, porosity, interconnectivity and internal and external architectures. The high printing resolution, precision and controllability of the PED allow for closer mimicry of tissues and organs. The PED expands its library of biopolymers by introducing an assisting cooling (AC) device which increases the working extrusion temperature from 120 to 250 deg. C. This paper investigates the PED with the integrated AC's capabilities to fabricate three-dimensional scaffolds that support cell growth, attachment and proliferation. Studies carried out in this paper utilized a biopolymer whose melting point is established to be 200 deg. C. This polymer was selected to illustrate the newly developed device's ability to fabricate three-dimensional scaffolds from a new library of biopolymers. Three-dimensional scaffolds fabricated with the integrated AC device should illustrate structural integrity and ability to support cell attachment and proliferation.

  20. Influence of Increasing Deposition Temperature on Electrical Properties of Amorphous Carbon Thin Film Prepared by Aerosol-Assisted Thermal CVD

    International Nuclear Information System (INIS)

    This paper reports on the successful deposition of p-type semiconducting amorphous carbon (paC) films fabricated onto the glass substrate by Aerosol-Assisted Thermal Chemical Vapor Deposition (CVD) using natural source of camphor oil as the precursor material. The analyze reveal that conductivity and resistivity shows some changes at different deposition temperature, that is the conductivity increase as temperature increase from 350 to 550 degree Celsius, but drop slightly at 550 degree Celsius. Other than that, optical and structural properties were also characterized by using UV-VIS-NIR system and Atomic Force Microscopy. The same trend of optical and electrical can be seen when the measurement from the Taucs plot expose a decreasing value of optical band gap as temperature increase, but slightly increase when temperature increase to 550 degree Celsius. (author)

  1. Aerosol assisted chemical vapour deposition of germanium thin films using organogermanium carboxylates as precursors and formation of germania films

    Indian Academy of Sciences (India)

    Alpa Y Shah; Amey Wadawale; Vijaykumar S Sagoria; Vimal K Jain; C A Betty; S Bhattacharya

    2012-06-01

    Diethyl germanium bis-picolinate, [Et2Ge(O2CC5H4N)2], and trimethyl germanium quinaldate, [Me3Ge(O2CC9H6N)], have been used as precursors for deposition of thin films of germanium by aerosol assisted chemical vapour deposition (AACVD). The thermogravimetric analysis revealed complete volatilization of complexes under nitrogen atmosphere. Germanium thin films were deposited on silicon wafers at 700°C employing AACVD method. These films on oxidation under an oxygen atmosphere at 600°C yield GeO2. Both Ge and GeO2 films were characterized by XRD, SEM and EDS measurements. Their electrical properties were assessed by current–voltage (–) characterization.

  2. Characteristics and properties of metal aluminum thin films prepared by electron cyclotron resonance plasma-assisted atomic layer deposition technology

    Institute of Scientific and Technical Information of China (English)

    Xiong Yu-Qing; Li Xing-Cun; Chen Qiang; Lei Wen-Wen; Zhao Qiao; Sang Li-Jun; Liu Zhong-Wei; Wang Zheng-Duo; Yang Li-Zhen

    2012-01-01

    Metal aluminum (Al) thin films are prepared by 2450 MHz electron cyclotron resonance plasma-assisted atomic layer deposition on glass and p-Si substrates using trimethylaluminum as the precursor and hydrogen as the reductive gas.We focus our attention on the plasma source for the thin-film preparation and annealing of the as-deposited films relative to the surface square resistivity.The square resistivity of as-deposited Al films is greatly reduced after annealing and almost reaches the value of bulk metal.Through chemical and structural analysis,we conclude that the square resistivity is determined by neither the contaminant concentration nor the surface morphology,but by both the crystallinity and crystal size in this process.

  3. Improving flux pinning in YBa[sub 2]Cu[sub 3]O[sub 7] coated conductors by changing the buffer layer deposition conditions

    Energy Technology Data Exchange (ETDEWEB)

    Maiorov, B. A. (Boris Alfredo); Wang, H. (Haiyan); Foltyn, S. R. (Stephen R.); Arendt, P. N. (Paul N.); Civale, L. (Leonardo)

    2004-01-01

    We present a comparative study of the flux pinning properties of YBa{sub 2}Cu{sub 3}O{sub 7} films deposited by pulsed laser deposition on polycrystalline metal substrates with a biaxially oriented MgO template produced by ion-beam-assisted deposition (IBAD), varying the deposition temperature (T{sub STO}) for the SrTiO{sub 3} buffer layer. We find that when T{sub STO} = T*{sub STO} = 820 C, the critical current density at self-field (J{sub c}{sup sf}) is maximized and the surface roughness minimized. On the contrary, in-field critical current density (J{sub c}) measurements show that at high fields, samples with T{sub STO}

  4. Deposition of cobalt and nickel sulfide thin films from thio- and alkylthio-urea complexes as precursors via the aerosol assisted chemical vapour deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Mgabi, L.P.; Dladla, B.S. [Department of Chemistry, University of Zululand, Private bag X1001 KwaDlangezwa, 3880 (South Africa); Malik, M.A. [School of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Garje, Shivram S. [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai 400098 (India); Akhtar, J. [Nanoscience and Materials Synthesis Lab, Department of Physics, COMSATS, Institute of Information Technology (CIIT), Chak shahzad, Islamabad (Pakistan); Revaprasadu, N., E-mail: RevaprasaduN@unizulu.ac.za [Department of Chemistry, University of Zululand, Private bag X1001 KwaDlangezwa, 3880 (South Africa)

    2014-08-01

    We report the synthesis of Co(II) and Ni(II) thiourea and alkylthiourea complexes by reacting the metal salts (CoCl{sub 2} and NiCl{sub 2}) with the thiourea, phenylthiourea and dicyclohexylthiourea ligands in a 1:2 ratio. The complexes, [CoCl{sub 2}(CS(NH{sub 2}){sub 2}){sub 2}] (I), [CoCl{sub 2}(CSNHC{sub 6}H{sub 5}NH{sub 2}){sub 2} (II) and [CoCI{sub 2}(SC(NHC{sub 6}H{sub 11}){sub 2}){sub 2}] (III), [NiCl{sub 2}(CS(NH{sub 2}){sub 2}){sub 2}] (IV), [NiCl{sub 2}(CSNHC{sub 6}H{sub 5}NH{sub 2}){sub 2}] (V) and [NiCl{sub 2}(SC(NHC{sub 6}H{sub 11}){sub 2}){sub 2}] (VI) were characterized by C, H, N analysis and Fourier transform infrared spectroscopy. Thermogravimetric analysis shows that all complexes undergo a two step decomposition process except for [NiCl{sub 2}(CSNHC{sub 6}H{sub 5}NH{sub 2}){sub 2}] (V) which decomposes in a single step. The complexes were used as single-source precursors for the deposition of cobalt sulfide and nickel sulfide thin films by aerosol assisted chemical vapor deposition at temperatures between 350 an 500 °C. The crystallinity of the films was determined by X-ray diffraction and their morphology was determined by scanning electron microscopy. The morphology of the cobalt sulfide thin films varies from randomly oriented platelets, to granulated spheres and cubes as the precursor and deposition conditions are changed. For nickel sulfide, the [NiCl{sub 2}(CS(NH{sub 2}){sub 2}){sub 2}] (IV) complex gave rods whereas the [NiCl{sub 2}(CSNHC{sub 6}H{sub 5}NH{sub 2}){sub 2}] (V) produced spherical particles. - Highlights: • We report the synthesis of Co(II) and Ni(II) thiourea and alkylthiourea complexes. • C, H, N analysis and Fourier transform infrared spectroscopy characterization • NiS and CoS thin films deposited by aerosol assisted chemical vapor deposition • X-ray diffraction characterization of the phase of the films • Film morphology determined by scanning electron microscopy.

  5. XPS study of target poisoning during the plasma assisted deposition of a-C:H/Au thin films

    International Nuclear Information System (INIS)

    The X-ray photoelectron spectroscopic (XPS) study of the target poisoning during the deposition of a-C:H/Au using combined radio frequency (RF) powered magnetron sputtering at 100 W and plasma-assisted chemical vapor deposition (PACVD) with a mass flow ratio of 0.5 between CH4 and at is made by Gampp. In this paper we extend this study to both RF and bipolar pulsed (BPP) powered magnetron sputtering in gas mixtures of different values of CH4/Ar mass flow ratio. Elemental compositions of deposited a-C:H/Au layers have been determined by in situ X-ray photoelectron spectroscopy. To determine the elemental content of a sample, the integration over Au 4f7/2, C 1s and 0 1s core level signals (oxygen shows up as an impurity of max. 1 at.%) was used. One may generally conclude that the character of target poisoning process is steep and step-like in time regardless of the type of magnetron power supply, i.e. that it is inherent to the deposition of a-C:H/Au using present deposition setup. Therefore, in the attempts to obtain stable and reproducible deposition conditions and homogeneous coatings, the target had to be driven to the certain degree of poisoning. This is done by conditioning in pure CH4 (covering) and in pure Ar plasma (cleaning) subsequently and alternatively, until the desired Au content is reached. Then, for deposition purposes, a CH4/Ar gas mixture was selected so that steady state of target covering and cleaning is sustained

  6. Spatio-selective surface modification of glass assisted by laser-induced deposition of gold nanoparticles

    International Nuclear Information System (INIS)

    Using pulsed laser irradiation (532 nm), dodecanethiol-capped gold nanoparticles (DT-Au) were deposited on the laser-irradiated region of a hydrophobic glass substrate modified with dimethyloctadecylchlorosilane (DMOS). After removal of deposited DT-Au, the laser-deposited region on the substrate was hydrophilic, as verified by static water contact angles. X-ray photoelectron spectroscopy suggested that the naked glass surface was not exposed at the hydrophilic region. Immersion of the substrate into gold nanorod (NR) solution selectively immobilized NRs on the hydrophilic surface via electrostatic interactions, indicating that the hydrophilic region was an anionic surface. From these results, it is expected that some immobilized DMOS groups on the laser-irradiated region of the substrate were oxidized during DT-Au deposition and fragmentation of the deposited DT-Au

  7. Enhancing the thermal conductivity of polymer-assisted deposited Al2O3 film by nitrogen doping

    Institute of Scientific and Technical Information of China (English)

    Huang Jiang; Zhang Yin; Pan Tai-Song; Zeng Bo; Hu Guo-Hua; Lin Yuan

    2012-01-01

    Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 (AlON) thin films on Si(100) substrates.The chemical compositions,crystallinity,and thermal conductivity of the as-grown films have been characterized by X-ray photoelectron spectroscopy (XPS),X-ray diffraction (XRD),and 3-omega method,respectively.Amorphous and polycrystalline Al2O3 and AlON thin films have been formed at 700 ℃ and 1000 ℃.The thermal conductivity results indicated that the effect of nitrogen doping on the thermal conductivity is determined by the competition of the increase of Al-N bonding and the suppression of crystallinity.A 67% enhancement in thermal conductivity has been achieved for the samples grown at 700 ℃,demonstrating that the nitrogen doping is an effective way to improve the thermal performance of polymer-assisted-deposited Al2O3 thin films at a relatively low growth temperature.

  8. Investigation of the physical properties of ion assisted ZrN thin films deposited by RF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Signore, M A; Valerini, D; Rizzo, A; Tapfer, L; Capodieci, L; Cappello, A [ENEA, Department of Physical Technologies and New Materials, SS7, Appia, km 706, 72100 Brindisi (Italy)

    2010-06-09

    Ion bombardment during thin film growth is known to cause structural and morphological changes in the deposited films, thus affecting their physical properties. In this work zirconium nitride films have been deposited by the ion assisted magnetron sputtering technique. The ion energy is controlled by varying the voltage applied to the substrate in the range 0-25 V. The deposited ZrN films are characterized for their structure, surface roughness, oxygen contamination, optical reflectance and electrical resistivity. With increasing substrate voltage crystallinity of the films is enhanced with a preferential orientation of the ZrN grains having the (1 1 1) axis perpendicular to the substrate surface. At the same time, a decrease in electrical resistivity and oxygen contamination content is observed up to 20 V. A higher substrate voltage (25 V) causes an inversion in the observed experimental trends. The role of oxygen contamination decrease and generation of nitrogen vacancies due to ionic assistance have been considered as a possible explanation for the experimental results.

  9. Surface chemistry of plasma-assisted atomic layer deposition of Al2O3 studied by infrared spectroscopy

    International Nuclear Information System (INIS)

    The surface groups created during plasma-assisted atomic layer deposition (ALD) of Al2O3 were studied by infrared spectroscopy. For temperatures in the range of 25-150 deg. C, -CH3 and -OH were unveiled as dominant surface groups after the Al(CH3)3 precursor and O2 plasma half-cycles, respectively. At lower temperatures more -OH and C-related impurities were found to be incorporated in the Al2O3 film, but the impurity level could be reduced by prolonging the plasma exposure. The results demonstrate that -OH surface groups rule the surface chemistry of the Al2O3 process and likely that of plasma-assisted ALD of metal oxides from organometallic precursors in general

  10. Microstructure and photoluminescence of Er-doped SiOx films synthesized by ion beam assisted deposition

    Institute of Scientific and Technical Information of China (English)

    Duan Shu-Qing; Tan Na; Zhang Qing-Yu

    2005-01-01

    Er-doped Sio_ films were synthesized at 500℃ by ion beam assisted deposition technique and annealed at 800 and 1100℃ for 2h in the air atomosphere. The analysis by using energy dispersive x-ray spectroscopy showed that the ratio of Si to O decreased from 3 in the as-deposited films to about 1 in the annealed films. The investigation by using transmission electron microscopy and x-ray diffraction inducated that annealing induces a microstructure change from amorphous to crystlline. The grain sizes in the films were about 10 and 40nm when annealed at 800 and 1100℃, respectively. The films annealed at temperatures of 800 and 1100℃ exhibited a sharp photoluminescence (PL) at 1.533μm from the Er centres when pumped by 980nm laser. The influence of microstructure and grain size on the PL from Er-doped Sio_ films has been studies and discussed.

  11. Ionic liquid-assisted growth of DBTTF-TCNQ complex organic crystals by vacuum co-deposition

    Science.gov (United States)

    Kuroishi, Kohei; Maruyama, Shingo; Ohashi, Noboru; Watanabe, Mio; Naito, Kenta; Matsumoto, Yuji

    2016-11-01

    High-crystalline DBTTF-TCNQ charge-transfer complex crystals with larger grains visible even by an optical microscope have been successfully grown, assisted by ionic liquid (IL) in vacuum co-deposition. Although the charge transfer reaction between the DBTTF and TCNQ molecules was ready to occur to form the complex regardless of the presence or absence of the IL even at room temperature, the subsequent crystal growth of the DBTTF-TCNQ complexes was enhanced by the IL, especially much more at temperatures higher than room temperature, leading to a significant improvement in the crystallinity of the complexes. The crystal growth mechanism of the DBTTF-TCNQ complexes in the IL was discussed based on the results of in situ optical microscope observation during the deposition of the DBTTF and TCNQ molecules into the IL.

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

    Science.gov (United States)

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

    2016-05-01

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

  13. Deposition of matrix-free fullerene films with improved morphology by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren;

    2013-01-01

    Thin films of C60 were deposited by matrix-assisted pulsed laser evaporation (MAPLE) from a frozen target of anisole with 0.67 wt% C60. Above a fluence of 1.5 J/cm2 the C60 films are strongly non-uniform and are resulting from transfer of matrix-droplets containing fullerenes. At low fluence...... the fullerene molecules in the films are intact, the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the film. This may indicate a regime of dominant evaporation at low fluence which merges into the MAPLE regime of liquid ejection of the host matrix...

  14. Matrix-Assisted Pulsed Laser Thin Film Deposition by Using Nd:YAG Laser

    Directory of Open Access Journals (Sweden)

    Francesco Bloisi

    2012-01-01

    In this paper, the MAPLE technique is described in details, together with a survey of current and possible future applications for both organic and biomaterial deposition taking into account the advantages of using an Nd:YAG laser. Beside other results, we have experimental confirmation that MAPLE applications are not limited to transparent molecules highly soluble in light absorbing solvent, thus allowing deposition of poorly soluble light absorbing molecules suspended in a light transparent liquid.

  15. Study of titania nanorod films deposited by matrix-assisted pulsed laser evaporation as a function of laser fluence

    Science.gov (United States)

    Caricato, A. P.; Belviso, M. R.; Catalano, M.; Cesaria, M.; Cozzoli, P. D.; Luches, A.; Manera, M. G.; Martino, M.; Rella, R.; Taurino, A.

    2011-11-01

    Chemically synthesized brookite titanium dioxide (TiO2) nanorods with average diameter and length dimensions of 3-4 nm and 35-50 nm, respectively, were deposited by the matrix-assisted pulsed laser evaporation technique. A toluene nanorod solution was frozen at the liquid-nitrogen temperature and irradiated with a KrF excimer laser ( λ=248 nm, τ=20 ns) at the repetition rate of 10 Hz, at different fluences (25 to 350 mJ/cm2). The deposited films were structurally characterized by high-resolution scanning and transmission electron microscopy. single-crystal Si wafers and carbon-coated Cu grids were used as substrates. Structural analyses evidenced the occurrence of brookite-phase crystalline nanospheres coexisting with individually distinguishable TiO2 nanorods in the films deposited at fluences varying from 50 to 350 mJ/cm2. Nanostructured TiO2 films comprising only nanorods were deposited by lowering the laser fluence to 25 mJ/cm2. The observed shape and phase transitions of the nanorods are discussed taking into account the laser-induced heating effects, reduced melting temperature and size-dependent thermodynamic stability of nanoscale TiO2.

  16. Redeposition in plasma-assisted atomic layer deposition: Silicon nitride film quality ruled by the gas residence time

    Energy Technology Data Exchange (ETDEWEB)

    Knoops, Harm C. M., E-mail: h.c.m.knoops@tue.nl, E-mail: w.m.m.kessels@tue.nl [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Oxford Instruments Plasma Technology, North End, Bristol BS49 4AP (United Kingdom); Peuter, K. de; Kessels, W. M. M., E-mail: h.c.m.knoops@tue.nl, E-mail: w.m.m.kessels@tue.nl [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

    2015-07-06

    The requirements on the material properties and growth control of silicon nitride (SiN{sub x}) spacer films in transistors are becoming ever more stringent as scaling of transistor structures continues. One method to deposit high-quality films with excellent control is atomic layer deposition (ALD). However, depositing SiN{sub x} by ALD has turned out to be very challenging. In this work, it is shown that the plasma gas residence time τ is a key parameter for the deposition of SiN{sub x} by plasma-assisted ALD and that this parameter can be linked to a so-called “redeposition effect”. This previously ignored effect, which takes place during the plasma step, is the dissociation of reaction products in the plasma and the subsequent redeposition of reaction-product fragments on the surface. For SiN{sub x} ALD using SiH{sub 2}(NH{sup t}Bu){sub 2} as precursor and N{sub 2} plasma as reactant, the gas residence time τ was found to determine both SiN{sub x} film quality and the resulting growth per cycle. It is shown that redeposition can be minimized by using a short residence time resulting in high-quality films with a high wet-etch resistance (i.e., a wet-etch rate of 0.5 nm/min in buffered HF solution). Due to the fundamental nature of the redeposition effect, it is expected to play a role in many more plasma-assisted ALD processes.

  17. Effects of deposition conditions on gas-barrier performance of SiOxNy thin films formed via ion-beam-assisted vapor deposition

    International Nuclear Information System (INIS)

    SiOxNy thin films were synthesized via ion-beam-assisted vapor deposition (IVD) where deposition of SiOx was irradiated by nitrogen ions. Firstly, reasonable-cost evaporation materials showing less splashing for the SiOx films were investigated by selecting appropriate sintering condition regimes of Si and SiO2 mixed powders. The SiOxNy thin films on a polyethylene terephtalate film substrate obtained via IVD showed a low oxygen transmission rate (OTR) of less than 1 cm3/m2 day. Effective nitrogen ion irradiation energy per atom was 8 eV/at. or greater, which is consistent with regimes where densification of thin films is reported to occur. Higher N2 partial pressure yielded a lower OTR and a higher nitrogen atomic ratio of the films obtained. It is suggested that the improvement in gas-barrier performance resulted from densification and chemical change of the films due to energy addition and nitrification produced by nitrogen ion-beam irradiation

  18. Fabrication of nanowires of Al-doped ZnO using nanoparticle assisted pulsed laser deposition (NAPLD) for device applications

    Energy Technology Data Exchange (ETDEWEB)

    Thanka Rajan, S. [ECMS Division, CSIR – Central Electrochemical Research Institute, Karaikudi 630 006 (India); Subramanian, B., E-mail: subramanianb3@gmail.com [ECMS Division, CSIR – Central Electrochemical Research Institute, Karaikudi 630 006 (India); Nanda Kumar, A.K.; Jayachandran, M. [ECMS Division, CSIR – Central Electrochemical Research Institute, Karaikudi 630 006 (India); Ramachandra Rao, M.S. [Department of Physics, Indian Institute of Technology Madras, Chennai 600 036 (India)

    2014-01-25

    Graphical abstract: -- Highlights: • Novel technique of NP assisted PLD was employed to obtain Al doped ZnO. • AZO nano wires with aspect ratios exceeding 20 were obtained at 500 sccm Ar gas pressure. • AZO films belong to the most stable wurtzite type. • Films show near band edge emission and defect related emission. -- Abstract: Aluminium doped zinc oxide (AZO) nanostructures have been successfully synthesized on sapphire substrates by using nanoparticle assisted pulsed laser deposition (NAPLD) in Ar atmosphere without using any catalyst. The growth of the AZO nanowires has been investigated by varying the argon flow rates. The coatings have been characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Atomic force microscopy (AFM), Diffuse Reflectance Spectroscopy (DRS), Laser Raman spectroscopy and Photoluminescence spectroscopy. The results of XRD indicate that the deposited films are crystalline ZnO with hexagonal wurtzite structure with (0 0 2) preferred orientation. FESEM images also clearly reveal the hexagonal structure and the formation of nanowires with aspect ratios between 15 and 20. The surface roughness value of 9.19 nm was observed from AFM analysis. The optical properties of the sample showed that under excitation with λ = 325 nm, an emission band was observed in UV and visible region. The characteristic Raman peaks were detected at 328, 380, 420, 430 cm{sup −1}.

  19. Deposition of organic dyes for dye-sensitized solar cell by using matrix-assisted pulsed laser evaporation

    Directory of Open Access Journals (Sweden)

    Chih-Ping Yen

    2016-08-01

    Full Text Available The deposition of various distinct organic dyes, including ruthenium complex N3, melanin nanoparticle (MNP, and porphyrin-based donor-π-acceptor dye YD2-o-C8, by using matrix-assisted pulsed laser evaporation (MAPLE for application to dye-sensitized solar cell (DSSC is investigated systematically. It is found that the two covalently-bonded organic molecules, i.e., MNP and YD2-o-C8, can be transferred from the frozen target to the substrate with maintained molecular integrity. In contrast, N3 disintegrates in the process, presumably due to the lower bonding strength of metal complex compared to covalent bond. With the method, DSSC using YD2-o-C8 is fabricated, and an energy conversion efficiency of 1.47% is attained. The issue of the low penetration depth of dyes deposited by MAPLE and the possible resolution to it are studied. This work demonstrates that MAPLE could be an alternative way for deposition of organic dyes for DSSC.

  20. Surface-grafted polymer-assisted electroless deposition of metals for flexible and stretchable electronics.

    Science.gov (United States)

    Liu, Xuqing; Zhou, Xuechang; Li, Yi; Zheng, Zijian

    2012-05-01

    Surface-grafted polymers, that is, ultrathin layers of polymer coating covalently tethered to a surface, can serve as a particularly promising nanoplatform for electroless deposition (ELD) of metal thin films and patterned structures. Such polymers consist of a large number of well-defined binding sites for highly efficient and selective uptake of ELD catalysts. Moreover, the polymer chains provide flexible 3D network structures to trap the electrolessly deposited metal particles, leading to strong metal-substrate adhesion. In the past decade, surface-grafted polymers have been demonstrated as efficient nanoplatforms for fabricating durable and high-performance metal coatings by ELD on plastic substrates for applications in flexible and stretchable electronics. This focus review summarizes these recent advances, with a particular focus on applications in polymeric flexible and stretchable substrates. An outlook on the future challenges and opportunities in this field is given at the end of this paper. PMID:22392811

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

    International Nuclear Information System (INIS)

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

  2. Resonant vibrational excitation of ethylene molecules in laser-assisted diamond deposition

    Science.gov (United States)

    Fan, L. S.; Zhou, Y. S.; Wang, M. X.; Gao, Y.; Liu, L.; Silvain, J. F.; Lu, Y. F.

    2014-07-01

    The influence of resonant vibrational excitation of ethylene molecules in combustion chemical vapor deposition of diamond was investigated. Resonant vibrational excitation of the CH2-wagging mode (a type c fundamental band, υ7, at 949.3 cm-1) in ethylene molecules was achieved by using a wavelength-tunable CO2 laser with a matching wavelength at 10.532 µm. By comparing to laser irradiation at off-resonance wavelengths, an on-resonance vibrational excitation is more efficient in energy coupling, increasing flame temperatures, accelerating the combustion reactions, and promoting diamond deposition. An enhanced rate of 5.7 was achieved in terms of the diamond growth rate with an improved diamond quality index at a high flame temperature under a resonant excitation of the CH2-wagging mode. This study demonstrates that a resonant vibrational excitation is an effective route for coupling energy into the gas phase reactions and promoting the diamond synthesis process.

  3. Electroless deposition of metal nanoparticles on graphene with substrate-assisted techniques

    Science.gov (United States)

    Zaniewski, Anna M.; Trimble, Christie J.; Meeks, Veronica; Nemanich, Robert J.

    2015-03-01

    We present the electroless reduction of solution-based metal ions for nanoparticle deposition on a variety of substrates. The substrates include graphene-coated metals, insulators, doped semiconductors, and patterned ferroelectrics. We find that the metal ions are spontaneously reduced on a wide variety of graphene substrates, and the substrates play a large role in the nanoparticle coverage. For example, the reduction of gold chloride to gold nanoparticles on graphene/lithium niobate results in 3% nanoparticle coverage compared to 20% coverage on graphene/silicon and 60% on graphene/copper. Given that the work function of graphene is approximately 4.4eV, the Fermi level is -0.1 V vs the normal hydrogen electrode (NHE). Since the reduction potential of gold chloride is +1.002 V, the spontaneous transfer of electrons from the graphene to the metal ion is energetically favorable. However, we find substrates with similar work functions nevertheless result in varied deposition rates, which we attribute to electron availability. We also find that patterned ferrolectrics can be used as a template for patterned nanoparticle deposition, with and without graphene. This work is supported by the National Science Foundation under Grant # DMR-1206935.

  4. Characterization of diamond thin films deposited by a CO2 laser-assisted combustion-flame method

    International Nuclear Information System (INIS)

    Diamond thin films were deposited by a CO2 laser-assisted O2/C2H2/C2H4 combustion-flame process. The effect of the deposition parameters, in particular the laser wavelength and power, on the film surface morphology, microstructure and phases present was the primary focus of the work. The laser power was set at 100, 400 and 800 W while the wavelength was varied and set at 10.591 μm in the untuned condition and set at 10.532 μm to resonantly match the CH2-wagging vibrational mode of the C2H4 molecule when in the tuned condition. When the laser was coupled to the combustion flame during deposition the diamond film growth was enhanced as the lateral grain size increased from 1 μm to greater than 5 μm. The greatest increase in grain size occurred when the wavelength was in the tuned condition. Scanning transmission electron microscopy images from focused-ion beam cross-sectioned samples revealed a sub-layer of smaller grains less than 1 μm in size near the substrate surface at the lower laser powers and untuned wavelength. X-ray diffraction results showed a more intense Diamond (111) peak as the laser power increased from 100 to 800 W for the films deposited with the tuned laser wavelength. Micro-Raman spectra showed a diamond peak nearly twice as intense from the films with the tuned laser wavelength.

  5. Surface hydrophobic modification of cellulose membranes by plasma-assisted deposition of hydrocarbon films

    Directory of Open Access Journals (Sweden)

    Mudtorlep Nisoa

    2010-03-01

    Full Text Available Surface modification by plasma polymerization is an efficient method to change the surface properties of a membrane. Desirable functionality such as hydrophobicity or hydrophilicity can be obtained, depending on plasma chemistry of gas precursors and discharge conditions. In this work, RF magnetron plasma is produced using acetylene and nitrogen as precursor gases. Variations of RF power, particle flux, deposited time and pressure of the precursor gases have been made to observe coating effects on the cellulose membranes. When appropriated conditions are used, a thin brownish film of hydrocarbon was formed on the membrane, and the water contact angle increased from 35 to 130 degrees.

  6. Synthesis of diamond-like carbon films on Si substrates by photoemission-assisted plasma-enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Meng [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Ogawa, Shuichi, E-mail: ogasyu@tagen.tohoku.ac.jp [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Takabayashi, Susumu; Otsuji, Taiichi [Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Core Research for Evolutionary Science and Technology, Japan Science and Technology Agency, K' s Gobancho Bldg., 7 Gobancho, Chiyoda-ku, Tokyo 102-0076 (Japan); Takakuwa, Yuji [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2012-11-15

    Diamond-like carbon (DLC) films grown by photoemission-assisted plasma-enhanced chemical vapor deposition (PA-PECVD) have attracted attention as a gate insulator for graphene-channel field effect transistors (GFETs). In this study, the possibility of using PA-PECVD to grow insulating DLC films for GFETs is explored by focusing on the growth rate and uniformity of DLC films on Si substrates. Initially, the DLC films were formed at a constant rate but the growth rate decreased rapidly when the thickness reached approximately 400 nm. This is because of a decrease in photoelectron emissions from the Si substrates as they are covered by DLC films which absorb UV photons. However, the DLC films formed uniformly at thicknesses less than 16%. This result indicates that PA-PECVD is a promising method for growing DLC films as the gate dielectric layer of GFETs.

  7. Growth of large size diamond single crystals by plasma assisted chemical vapour deposition: Recent achievements and remaining challenges

    Science.gov (United States)

    Tallaire, Alexandre; Achard, Jocelyn; Silva, François; Brinza, Ovidiu; Gicquel, Alix

    2013-02-01

    Diamond is a material with outstanding properties making it particularly suited for high added-value applications such as optical windows, power electronics, radiation detection, quantum information, bio-sensing and many others. Tremendous progresses in its synthesis by microwave plasma assisted chemical vapour deposition have allowed obtaining single crystal optical-grade material with thicknesses of up to a few millimetres. However the requirements in terms of size, purity and crystalline quality are getting more and more difficult to achieve with respect to the forecasted applications, thus pushing the synthesis method to its scientific and technological limits. In this paper, after a short description of the operating principles of the growth technique, the challenges of increasing crystal dimensions both laterally and vertically, decreasing and controlling point and extended defects as well as modulating crystal conductivity by an efficient doping will be detailed before offering some insights into ways to overcome them.

  8. Properties of La and Nb-modified PZT thin films grown by radio frequency assisted pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Verardi, P. [CNR-Istituto di Acustica, Via del Fosso del Cavaliere 100, I-00133 Rome (Italy); Craciun, F. [CNR-Istituto dei Sistemi Complessi, Via del Fosso del Cavaliere 100, I-00133 Rome (Italy); Dinescu, M. [NILPRP, Bucharest, PO Box MG-16, RO-76900 (Romania)]. E-mail: dinescum@ifin.nipne.ro; Scarisoreanu, N. [NILPRP, Bucharest, PO Box MG-16, RO-76900 (Romania); Moldovan, A. [NILPRP, Bucharest, PO Box MG-16, RO-76900 (Romania); Purice, A. [NILPRP, Bucharest, PO Box MG-16, RO-76900 (Romania); Galassi, C. [CNR-ISTEC, Via Granarolo 64, I 48018 Faenza (Italy)

    2005-04-25

    Lead zirconate titanate ferroelectric thin films added with La and Nb has been grown by radio frequency assisted pulsed laser deposition on Pt/Si, starting from sintered targets. The dielectric properties were measured in a large frequency range and their dependence on the a.c. driving field amplitude has been investigated. A linear decreasing of the dielectric permittivity with frequency logarithm increasing has been evidenced. The most important factor for the driving field amplitude influence on the dielectric properties is the type of vacancies introduced by La and Nb substitutions, which indicates that the dynamics involved in a.c. field behavior is controlled by interaction mechanisms between ferroelectric domain or nanodomain walls and pinning (vacancies) centers.

  9. Monte Carlo simulation of the behaviour of electrons during electron-assisted chemical vapour deposition of diamond

    Institute of Scientific and Technical Information of China (English)

    董丽芳; 陈俊英; 董国义; 尚勇

    2002-01-01

    The behaviour of electrons during electron-assisted chemical vapour deposition of diamond is investigated using Monte Carlo simulation. The electron energy distribution and velocity distribution are obtained over a wide range of reduced field E/N (the ratio of the electric field to gas molecule density) from 100 to 2000 in units of 1Td=10-17Vcm2.Their effects on the diamond growth are also discussed. Themain results obtained are as follows. (1) The velocity profile is asymmetric for the component parallel to the field.Ihe velocity distribution has a peak shift in the field direction. Most electrons possess non-zero velocity parallel to the substrate. (2) The number of atomic H is a function of E/N. (3) High-quality diamond can be obtained under the condition of E/N from 50 to 800Td due to sufficient atomic H and electron bombardment.

  10. Numerical And Experimental Analysis Of Fracture Of Athrombogenic Coatings Deposited On Ventricular Assist Device In Micro-Shear Test

    Directory of Open Access Journals (Sweden)

    Kopernik M.

    2015-06-01

    Full Text Available The Polish left ventricular assist device (LVAD – RELIGA_EXT will be made of thermoplastic polycarbonate-urethane (Bionate II with deposited athrombogenic nano-coatings: gold (Au and titanium nitride (TiN. Referring to the physical model, the two-scale model of LVAD developed in the previous works in the authors’ finite element code is composed of a macro-model of blood chamber and a micro-model of wall: TiN, Au and Bionate II. The numerical analysis of stress and strain states confirmed the possibility of fracture based on localization of zones of the biggest values of triaxiality factor. The introduction of Au interlayer between TiN and polymer improved the toughness of the connection, and increased the compressive residual stress in the coating what resulted in reduction of stress and strain close to the boundary between substrate and coating.

  11. Properties of Erbium Doped Hydrogenated Amorphous Carbon Layers Fabricated by Sputtering and Plasma Assisted Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    V. Prajzler

    2008-01-01

    Full Text Available We report about properties of carbon layers doped with Er3+ ions fabricated by Plasma Assisted Chemical Vapor Deposition (PACVD and by sputtering on silicon or glass substrates. The structure of the samples was characterized by X-ray diffraction and their composition was determined by Rutherford Backscattering Spectroscopy and Elastic Recoil Detection Analysis. The Absorbance spectrum was taken in the spectral range from 400 nm to 600 nm. Photoluminescence spectra were obtained using two types of Ar laser (λex=514.5 nm, lex=488 nm and also using a semiconductor laser (λex=980 nm. Samples fabricated by magnetron sputtering exhibited typical emission at 1530 nm when pumped at 514.5 nm. 

  12. Polymer-assisted metal deposition (PAMD): a full-solution strategy for flexible, stretchable, compressible, and wearable metal conductors.

    Science.gov (United States)

    Yu, You; Yan, Casey; Zheng, Zijian

    2014-08-20

    Metal interconnects, contacts, and electrodes are indispensable elements for most applications of flexible, stretchable, and wearable electronics. Current fabrication methods for these metal conductors are mainly based on conventional microfabrication procedures that have been migrated from Si semiconductor industries, which face significant challenges for organic-based compliant substrates. This Research News highlights a recently developed full-solution processing strategy, polymer-assisted metal deposition (PAMD), which is particularly suitable for the roll-to-roll, low-cost fabrication of high-performance compliant metal conductors (Cu, Ni, Ag, and Au) on a wide variety of organic substrates including plastics, elastomers, papers, and textiles. This paper presents i) the principles of PAMD, and how to use it for making ii) flexible, stretchable, and wearable conductive metal electrodes, iii) patterned metal interconnects, and d) 3D stretchable and compressible metal sponges. A critical perspective on this emerging strategy is also provided. PMID:24458846

  13. Role of fluorine atoms in the oxidation-hydrolysis process of plasma assisted chemical vapor deposition fluorinated silicon nitride film

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, O.; Gomez-Aleixandre, C.; Palacio, C. (Universidad Autonoma de Madrid (Spain))

    The oxidation and/or hydrolysis of a plasma assisted chemical vapor deposition fluorinated silicon nitride film in a moisture atmosphere has been studied. The film presents fluorine atoms incorporated as -SiF, -SiF[sub 2], -SiF[sub 3], and [-SiF[sub 2]-][sub n] groups. The open structure of the film, due to the high fluorine content as [-SiF[sub 2]-][sub n], favors the penetration of oxygen and water molecules in the network. The evolution of the film has been explained by the different reactivity of the silicon atoms depending on their chemical environment. The role of fluorine atoms incorporated into the film has been established. 12 refs., 3 figs., 1 tab.

  14. Ion-assisted deposition of yttrium fluoride as a substitute for thorium fluoride: application to infrared antireflection coating on germanium

    Science.gov (United States)

    Robic, Jean-Yves; Rolland, Bernard; Deutsch, Jean-Claude; Gallais, Patrick

    1994-11-01

    Yttrium fluoride has been proposed as a substitute for thorium fluoride in anti-reflection coatings for the infrared range. We have studied the ion assisted deposition (IAD) of YF3 in order to obtain dense and low absorbency layers in the 8 to 12 mm spectral window. Refractive index and extinction coefficient of this fluoride were determined from spectrophotometry measurements. We have then associated the YF3 with ZnS and Ge layers so as to obtain four layer anti-reflection coatings on germanium. The stress induced by each layer in the coating was measured and the sum was shown to be equal to the stress of the total coating. Eventually, an industrial, high efficiency, both side anti-reflection coating on germanium was developed using IAD YF3 film.

  15. In-situ photo-assisted deposition of silver particles on hydrogel fibers for antibacterial applications

    International Nuclear Information System (INIS)

    Silver nanoparticles (AgNPs) have attracted intensive research interest and have been recently incorporated in polymers, medical devices, hydrogels and burn dressings to control the proliferation of microorganisms. In this study a novel silver antibacterial coating was deposited for the first time on hydrogel fibers through an in-situ photo-chemical reaction. Hydrogel blends obtained by mixing different percentages of silver-treated and untreated fibers were characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Four different fluids, such as phosphate buffered saline (PBS), simulated body fluid (SBF), chemical simulated wound fluid (cSWF), and deionized water (DI water), were used for evaluating the swelling properties. The results obtained confirmed that the presence of silver did not affect the properties of the hydrogel. Moreover, the results obtained through inductively coupled plasma mass spectrometry (ICP-MS) demonstrated very low silver release values, thus indicating the perfect adhesion of the silver coating to the substrate. Good antibacterial capabilities were demonstrated by any hydrogel blend on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) through agar diffusion tests and optical density readings. - Highlights: • An innovative nano-silver deposition technique was adopted on hydrogel fibers. • Antibacterial effects was verified by agar diffusion and optical density tests. • The swelling properties were investigated using 4 different fluids. • Hydrogel blends with different percentages of silver-treated fibers were compared

  16. In-situ photo-assisted deposition of silver particles on hydrogel fibers for antibacterial applications

    Energy Technology Data Exchange (ETDEWEB)

    Raho, Riccardo [Department of Engineering for Innovation, University of Salento, Via per Monteroni, 73100 Lecce (Italy); CBN, Center for Biomolecular Nanotechnologies, Fondazione Istituto Italiano di Tecnologia, Via Barsanti, 73010 Arnesano, Lecce (Italy); Paladini, Federica; Lombardi, Fiorella Anna [Department of Engineering for Innovation, University of Salento, Via per Monteroni, 73100 Lecce (Italy); Boccarella, Sandro [Megatex S.p.A., Via Cima D' Aosta, 73040 Melissano, Lecce (Italy); Zunino, Benedetta [Università Cattolica del Sacro Cuore, Largo Francesco Vito 1, 00198 Roma (Italy); Pollini, Mauro, E-mail: mauro.pollini@unisalento.it [Department of Engineering for Innovation, University of Salento, Via per Monteroni, 73100 Lecce (Italy); Silvertech Ltd., Via per Monteroni, 73100 Lecce (Italy)

    2015-10-01

    Silver nanoparticles (AgNPs) have attracted intensive research interest and have been recently incorporated in polymers, medical devices, hydrogels and burn dressings to control the proliferation of microorganisms. In this study a novel silver antibacterial coating was deposited for the first time on hydrogel fibers through an in-situ photo-chemical reaction. Hydrogel blends obtained by mixing different percentages of silver-treated and untreated fibers were characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Four different fluids, such as phosphate buffered saline (PBS), simulated body fluid (SBF), chemical simulated wound fluid (cSWF), and deionized water (DI water), were used for evaluating the swelling properties. The results obtained confirmed that the presence of silver did not affect the properties of the hydrogel. Moreover, the results obtained through inductively coupled plasma mass spectrometry (ICP-MS) demonstrated very low silver release values, thus indicating the perfect adhesion of the silver coating to the substrate. Good antibacterial capabilities were demonstrated by any hydrogel blend on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) through agar diffusion tests and optical density readings. - Highlights: • An innovative nano-silver deposition technique was adopted on hydrogel fibers. • Antibacterial effects was verified by agar diffusion and optical density tests. • The swelling properties were investigated using 4 different fluids. • Hydrogel blends with different percentages of silver-treated fibers were compared.

  17. Synthesis of CdS nanostructures using template-assisted ammonia-free chemical bath deposition

    Science.gov (United States)

    Preda, N.; Enculescu, M.; Gherendi, F.; Matei, E.; Toimil-Molares, M. E.; Enculescu, I.

    2012-09-01

    CdS micro- and nano-structures (micro/nanotubes and nanostructured films) were obtained by ammonia-free chemical bath deposition using polymer templates (ion track-etched polycarbonate membranes and poly(styrene-hydroxyethyl methacrylate) nanosphere arrays). The semiconductor structures were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), optical absorption, photoluminescence and electrical measurements. The diameters of CdS tubes are between 300 nm and few microns and the lengths are up to tens of micrometers. The SEM images prove that the CdS films are nanostructured due to the deposition on the polymer nanosphere arrays. For both CdS structures (tubes and films) the XRD patterns show a hexagonal phase. The optical studies reveal a band gap value of about 2.5-2.6 eV and a red luminescence at ˜1.77 eV. A higher increase of conductivity is observed for illuminating the CdS nanostructured film when compared to the simple semiconductor film. This is a consequence of the periodic patterning induced by the polymer nanosphere array.

  18. Fabrication and gas sensing properties of pure and au-functionalised W03 nanoneedle-like structures, synthesised via aerosol assisted chemical vapour deposition method

    OpenAIRE

    Stoycheva, Toni

    2011-01-01

    In this doctoral thesis, it has been investigated and developed the Aerosol Assisted Chemical Vapour Deposition (AACVD) method for direct in-situ growth of intrinsic and Au-functionalised nanostructured WO3, as well as SnO2-based devices for gas sensing applications. The nanostructured material synthesis, device fabrication and their gas sensing properties have been studied. AACVD method was used for synthesis and direct deposition of sensing films onto classical alumina and microhotplat...

  19. Protective Sliding Carbon-Based Nanolayers Prepared by Argon or Nitrogen Ion-Beam Assisted Deposition on Ti6Al4V Alloy

    Directory of Open Access Journals (Sweden)

    Petr Vlcak

    2016-01-01

    Full Text Available The microstructure and the surface properties of samples coated by carbon-based nanolayer were investigated in an effort to increase the surface hardness and reduce the coefficient of friction of the Ti6Al4V alloy. Protective carbon-based nanolayers were fabricated by argon or nitrogen ion-beam assisted deposition at ion energy of 700 eV on Ti6Al4V substrates. The Raman spectra indicated that nanolayers had a diamond-like carbon character with sp2 rich bonds. The TiC and TiN compounds formed in the surface area were detected by X-ray diffraction. Nanoscratch tests showed increased adhesion of a carbon-based nanolayer deposited with ion assistance in comparison with a carbon nanolayer deposited without ion assistance. The results showed that argon ion assistance leads to greater nanohardness than a sample coated by a carbon-based nanolayer with nitrogen ion assistance. A more than twofold increase in nanohardness and a more than fivefold decrease in the coefficient of friction were obtained for samples coated by a carbon-based nanolayer with ion assistance, in comparison with the reference sample.

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-06-01

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

  2. Growth of Biaxially Textured Yttria-Stabilized Zirconia Thin Films on Si(111) Substrate by Ion Beam Assisted Deposition

    Institute of Scientific and Technical Information of China (English)

    MU Hai-Chuan; REN Cong-Xin; JIANG Bing-Yao; DING Xing-Zhao; YU Yue-Hui; WANG Xi; LIU Xiang-Huai; ZHOU Gui-En; JIA Yun-Bo

    2000-01-01

    The (001) oriented yttria-stabilized zirconia (YSZ) films with in-plane biaxial texture have been deposited on Si(lll ) substrates by ion beam assisted deposition at ambient temperature. The effects of ion/atom arrival rate ratio (R=(Ar+ +O2+)/ZrO2) and incident angle of bombarding ion beam on the film texture development were investigated. It was found that the in-plane biaxial texture of the films was improved gradually with increasing ion/atom arrival rate ratio R up to a critical value 1.9, but it was degraded with the further increase of R. The optimal in-plane biaxial texture, whose full width at half maximum of the (lll) φ-scan spectrum is 14°, can be obtained at R=1.9 and incident angle of 55°. For a fixed R, the optimal crystallinity and in-plane biaxial alignment of the YSZ films did not appear at the same incident angle and showed an opposite variation with the change of the incident angle from 51° to 55°. C-axis lignment (perpendicular to substrate surface) does not show any substantial variation with the change of incident angle within the range of 47° - 56°.

  3. Failure Strain and Strain-Stress Analysis in Titanium Nitride Coatings Deposited on Religa Heart Ext Ventricular Assist Device

    Directory of Open Access Journals (Sweden)

    Kopernik M.

    2015-04-01

    Full Text Available The Polish ventricular assist device is made of Bionate II with deposited TiN biocompatible nano-coating. The two scale finite element model is composed of a macro-model of blood chamber and a micro-model of the TiN/Bionate II. The numerical analysis of stress and strain states confirmed the possibility of fracture. Therefore, the identification of a fracture parameter considered as a failure strain is the purpose of the present work. The tensile test in a micro chamber of the SEM was performed to calibrate the fracture parameter of the material system TiN/Bionate II. The failure strain is a function of a temperature, a thickness of coating and parameters of surface's profile. The failure strain was calculated at the stage of the test, in which the initiation of fracture occurred. The finite element micro-model includes the surface roughness and the failure strain under tension condition for two thicknesses of coatings which will be deposited on the medical device.

  4. In Situ Nanocalorimetric Investigations of Plasma Assisted Deposited Poly(ethylene oxide)-like Films by Specific Heat Spectroscopy.

    Science.gov (United States)

    Madkou, Sherif; Melnichu, Iurii; Choukourov, Andrei; Krakovsky, Ivan; Biederman, Hynek; Schönhals, Andreas

    2016-04-28

    In recent years, highly cross-linked plasma polymers have started to unveil their potential in numerous biomedical applications in thin-film form. However, conventional diagnostic methods often fail due to their diverse molecular dynamics conformations. Here, glassy dynamics and the melting transition of thin PEO-like plasma assisted deposited (ppPEO) films (thickness 100 nm) were in situ studied by a combination of specific heat spectroscopy, utilizing a pJ/K sensitive ac-calorimeter chip, and composition analytical techniques. Different cross-linking densities were obtained by different plasma powers during the deposition of the films. Glassy dynamics were observed for all values of the plasma power. It was found that the glassy dynamics slows down with increasing the plasma power. Moreover, the underlying relaxation time spectra broaden indicating that the molecular motions become more heterogeneous with increasing plasma power. In a second set of the experiment, the melting behavior of the ppPEO films was studied. The melting temperature of ppPEO was found to decrease with increasing plasma power. This was explained by a decrease of the order in the crystals due to formation of chemical defects during the plasma process. PMID:27055060

  5. Polystyrene sphere monolayer assisted electrochemical deposition of ZnO nanorods with controlable surface density

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, D., E-mail: daniel.ramirez@ucv.c [Laboratorio de Electroquimica, Pontificia Universidad Catolica de Valparaiso, Valparaiso (Chile); Gomez, H. [Laboratorio de Electroquimica, Pontificia Universidad Catolica de Valparaiso, Valparaiso (Chile); Lincot, D. [Institute de Recherche et Developpement sur l' Energie Photovoltaique-IRDEP, 6 Quai Watier 78401, Chatou Cedex (France)

    2010-02-15

    In this paper we report the zinc oxide nanorods (ZnO NRs) growth by electrochemical deposition onto polycrystalline gold electrodes modified with assemblies of polystyrene sphere monolayers (PSSMs). Growth occurs through the interstitial spaces between the hexagonally close packed spheres. ZnO NRs nucleate in the region where three adjacent spheres leave a space, being able to grow and projected over the PSSMs. The nanorod surface density (N{sub NR}) shows a linear dependence with respect to a PS sphere diameter selected. XRD analysis shows these ZnO NRs are highly oriented along the (0 0 2) plane (c-axis). This open the possibility to have electronic devices with mechanically supported nanometric materials.

  6. Microstructural, chemical and textural characterization of ZnO nanorods synthesized by aerosol assisted chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Sáenz-Trevizo, A.; Amézaga-Madrid, P.; Fuentes-Cobas, L.; Pizá-Ruiz, P.; Antúnez-Flores, W.; Ornelas-Gutiérrez, C. [Centro de Investigación en Materiales Avanzados, S.C., Chihuahua, Chihuahua 31109 (Mexico); Pérez-García, S.A. [Centro de Investigación en Materiales Avanzados, S.C., Unidad Monterrey, Apodaca, Nuevo León 66600 (Mexico); Miki-Yoshida, M., E-mail: mario.miki@cimav.edu.mx [Centro de Investigación en Materiales Avanzados, S.C., Chihuahua, Chihuahua 31109 (Mexico)

    2014-12-15

    ZnO nanorods were synthesized by aerosol assisted chemical vapor deposition onto TiO{sub 2} covered borosilicate glass substrates. Deposition parameters were optimized and kept constant. Solely the effect of different nozzle velocities on the growth of ZnO nanorods was evaluated in order to develop a dense and uniform structure. The crystalline structure was characterized by conventional X-ray diffraction in grazing incidence and Bragg–Brentano configurations. In addition, two-dimensional grazing incidence synchrotron radiation diffraction was employed to determine the preferred growth direction of the nanorods. Morphology and growth characteristics analyzed by electron microscopy were correlated with diffraction outcomes. Chemical composition was established by X-ray photoelectron spectroscopy. X-ray diffraction results and X-ray photoelectron spectroscopy showed the presence of wurtzite ZnO and anatase TiO{sub 2} phases. Morphological changes noticed when the deposition velocity was lowered to the minimum, indicated the formation of relatively vertically oriented nanorods evenly distributed onto the TiO{sub 2} buffer film. By coupling two-dimensional X-ray diffraction and computational modeling with ANAELU it was proved that a successful texture determination was achieved and confirmed by scanning electron microscopy analysis. Texture analysis led to the conclusion of a preferred growth direction in [001] having a distribution width Ω = 20° ± 2°. - Highlights: • Uniform and pure single-crystal ZnO nanorods were obtained by AACVD technique. • Longitudinal and transversal axis parallel to the [001] and [110] directions, respectively. • Texture was determined by 2D synchrotron diffraction and electron microscopy analysis. • Nanorods have its [001] direction distributed close to the normal of the substrate. • Angular spread about the preferred orientation is 20° ± 2°.

  7. Ion-beam-assisted deposition of Al films with strong preferential orientation

    International Nuclear Information System (INIS)

    Preferential crystal orientation of Al films deposited under simultaneous argon-ion irradiation has been investigated by changing both the ion-to-atom arrival rate ratio (ion-atom ratio) and the ion energy. The intensity of the reflection, I(111), obtained from X-ray diffraction shows a drastic increase with ion irradiation, although the effect on other reflection peaks such as I(200) is only slight. The intensity ratio I(111)/I(200), a parameter for the electromigration resistance of Al films, has shown the highest value at a certain optimum ion-atom ratio. This optimum ion-atom ratio for each ion energy is found to shift toward lower values with increasing ion energy. Under the optimum conditions, the average ion energy per neutral atom after cascade collisions is found to be about 1.2 eV irrespective of the primary ion energy, which is comparable with the energy for the self-diffusion of Al (1.4 eV). The electrical measurements have shown that the resistivity of Al films increases considerably with simultaneous ion irradiation, however, it recovers to a level comparable with that of unassisted films by annealing at 400degC. (orig.)

  8. Characterization of amorphous yttria layers deposited by aqueous solutions of Y-chelate alkoxides complex

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Soon, E-mail: kyscjb@i-sunam.com; Lee, Yu-Ri; Kim, Byeong-Joo; Lee, Jae-Hun; Moon, Seung-Hyun; Lee, Hunju

    2015-01-15

    Highlights: • Economical method for crack-free amorphous yttria layer deposition by dip coating. • Simpler process for planar yttria film as a diffusion barrier and nucleation layer. • Easy control over the film properties with better characteristics. • Easy control over the thickness of the deposited films. • A feasible process that can be easily adopted by HTSCC industries. - Abstract: Crack-free amorphous yttria layers were deposited by dip coating in solutions of different Y-chelate alkoxides complex. Three Y-chelate solutions of different concentrations were prepared using yttrium acetate tetrahydrate, yttrium stearic acid as Y source materials. PEG, diethanolamine were used as chelating agents, while ethanol, methanol and tetradecane were used as solvent. Three different combinations of chelating and solvents were used to prepare solutions for Y{sub 2}O{sub 3} dip coating on SUS, electropolished and non-electropolished Hastelloy C-276 substrates. The thickness of the films was varied by changing the number of dipping cycles. At an optimized condition, the substrate surface roughness (rms) value was reduced from ∼50 nm to ∼1 nm over a 10 × 10 μm{sup 2} area. After Y{sub 2}O{sub 3} deposition, MgO was deposited using ion-beam assisted deposition (IBAD), then LaMnO{sub 3} (LMO) was deposited using sputtering and GdBCO was deposited using reactive co-evaporation by deposition and reaction (RCE-DR). Detailed X-ray study indicates that LMO/MgO/Y{sub 2}O{sub 3} and GdBCO/LMO/MgO/Y{sub 2}O{sub 3} stack films have good out-of-plane and in-plane textures with strong c-axis alignment. The critical current (Ic) of GdBCO/LMO/MgO/Y{sub 2}O{sub 3} multilayer structure varied from 190 to 420 A/cm with different solutions, when measured at 77 K. These results demonstrated that amorphous yttria can be easily deposited by dip coating using Y-chelates complex as a diffusion barrier and nucleation layer.

  9. Plasma assisted metal-organic chemical vapor deposition of hard chromium nitride thin film coatings using chromium(III) acetylacetonate as the precursor

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Arup; Kuppusami, P.; Lawrence, Falix; Raghunathan, V.S.; Antony Premkumar, P.; Nagaraja, K.S

    2004-06-15

    A new technique has been developed for depositing hard nanocrystalline chromium nitride (CrN) thin films on metallic and ceramic substrates using plasma assisted metal-organic chemical vapor deposition (PAMOCVD) technique. In this low temperature and environment-friendly process, a volatile mixture of chromium(III) acetylacetonate and either ammonium iodide or ammonium bifluoride were used as precursors. Nitrogen and hydrogen have been used as the gas precursors. By optimizing the processing conditions, a maximum deposition rate of {approx}0.9 {mu}m/h was obtained. A comprehensive characterization of the CrN films was carried out using X-ray diffraction (XRD), microhardness, and microscopy. The microstructure of the CrN films deposited on well-polished stainless steel (SS) showed globular particles, while a relatively smooth surface morphology was observed for coatings deposited on polished yittria-stabilized zirconia (YSZ)

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

    Institute of Scientific and Technical Information of China (English)

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

    2012-01-01

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

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

    International Nuclear Information System (INIS)

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

  12. Shadow-casted ultrathin surface coatings of titanium and titanium/silicon oxide sol particles via ultrasound-assisted deposition.

    Science.gov (United States)

    Karahan, H Enis; Birer, Özgür; Karakuş, Kerem; Yıldırım, Cansu

    2016-07-01

    Ultrasound-assisted deposition (USAD) of sol nanoparticles enables the formation of uniform and inherently stable thin films. However, the technique still suffers in coating hard substrates and the use of fast-reacting sol-gel precursors still remains challenging. Here, we report on the deposition of ultrathin titanium and titanium/silicon hybrid oxide coatings using hydroxylated silicon wafers as a model hard substrate. We use acetic acid as the catalyst which also suppresses the reactivity of titanium tetraisopropoxide while increasing the reactivity of tetraethyl orthosilicate through chemical modifications. Taking the advantage of this peculiar behavior, we successfully prepared titanium and titanium/silicon hybrid oxide coatings by USAD. Varying the amount of acetic acid in the reaction media, we managed to modulate thickness and surface roughness of the coatings in nanoscale. Field-emission scanning electron microscopy and atomic force microscopy studies showed the formation of conformal coatings having nanoroughness. Quantitative chemical state maps obtained by x-ray photoelectron spectroscopy (XPS) suggested the formation of ultrathin (coatings and thickness measurements by rotating analyzer ellipsometry supported this observation. For the first time, XPS chemical maps revealed the transport effect of ultrasonic waves since coatings were directly cast on rectangular substrates as circular shadows of the horn with clear thickness gradient from the center to the edges. In addition to the progress made in coating hard substrates, employing fast-reacting precursors and achieving hybrid coatings; this report provides the first visual evidence on previously suggested "acceleration and smashing" mechanism as the main driving force of USAD.

  13. Shadow-casted ultrathin surface coatings of titanium and titanium/silicon oxide sol particles via ultrasound-assisted deposition.

    Science.gov (United States)

    Karahan, H Enis; Birer, Özgür; Karakuş, Kerem; Yıldırım, Cansu

    2016-07-01

    Ultrasound-assisted deposition (USAD) of sol nanoparticles enables the formation of uniform and inherently stable thin films. However, the technique still suffers in coating hard substrates and the use of fast-reacting sol-gel precursors still remains challenging. Here, we report on the deposition of ultrathin titanium and titanium/silicon hybrid oxide coatings using hydroxylated silicon wafers as a model hard substrate. We use acetic acid as the catalyst which also suppresses the reactivity of titanium tetraisopropoxide while increasing the reactivity of tetraethyl orthosilicate through chemical modifications. Taking the advantage of this peculiar behavior, we successfully prepared titanium and titanium/silicon hybrid oxide coatings by USAD. Varying the amount of acetic acid in the reaction media, we managed to modulate thickness and surface roughness of the coatings in nanoscale. Field-emission scanning electron microscopy and atomic force microscopy studies showed the formation of conformal coatings having nanoroughness. Quantitative chemical state maps obtained by x-ray photoelectron spectroscopy (XPS) suggested the formation of ultrathin (thickness measurements by rotating analyzer ellipsometry supported this observation. For the first time, XPS chemical maps revealed the transport effect of ultrasonic waves since coatings were directly cast on rectangular substrates as circular shadows of the horn with clear thickness gradient from the center to the edges. In addition to the progress made in coating hard substrates, employing fast-reacting precursors and achieving hybrid coatings; this report provides the first visual evidence on previously suggested "acceleration and smashing" mechanism as the main driving force of USAD. PMID:26964975

  14. Bending strain effects on the critical current in Cu-stabilized IBAD/EDDC processed SmBCO coated conductor tape

    International Nuclear Information System (INIS)

    Influences of bending strain on the critical current, Ic, in Cu-stabilized IBAD/EDDC processed SmBCO coated conductor (CC) tapes were investigated at 77 K and self-field using a small-scale Goldacker type bending test rig. Considering the location of the superconducting layer against the neutral axis, tensile and compressive bending strains were applied to the SmBCO coating layer and the strain effect on Ic degradation was discussed. Under tensile bending strain, the Ic decreased monotonically but recovered reversibly up to the irreversible strain limit. Under compressive bending strain, however, the Ic increased but in some cases it suddenly dropped after straightening due to the delamination of the copper stabilizer. Also, repeated bending strains were applied to Cu-stabilized SmBCO CC samples in order to observe the behavior of Ic under cyclic loading. Ic Initially decreased with the application of 0.7% bending strain, but when the tape was subjected to repeated bending up to 100 cycles, no more degradation occurred. And finally, the Ic almost recovered to Ic0 when the tape was straightened

  15. Electrochemically assisted deposition of sol-gel bio-composite with co-immobilized dehydrogenase and diaphorase

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhijie [LCPME, UMR 7564, CNRS-Nancy University, 405, rue de Vandoeuvre, 54600 Villers-les-Nancy (France); Etienne, Mathieu, E-mail: mathieu.etienne@lcpme.cnrs-nancy.fr [LCPME, UMR 7564, CNRS-Nancy University, 405, rue de Vandoeuvre, 54600 Villers-les-Nancy (France); Kohring, Gert-Wieland [Mikrobiologie, Universitaet des Saarlandes, Campus, Geb. A1.5, D-66123 Saarbruecken (Germany); Bon-Saint-Come, Yemima; Kuhn, Alexander [Universite Bordeaux, ISM, ENSCPB, 16 avenue Pey Berland, 33607 Pessac (France); Walcarius, Alain [LCPME, UMR 7564, CNRS-Nancy University, 405, rue de Vandoeuvre, 54600 Villers-les-Nancy (France)

    2011-10-30

    We report here that the electrochemically assisted deposition (EAD) of silica thin films can be a good strategy to co-encapsulate D-sorbitol dehydrogenase (DSDH) and diaphorase in an active form. This is achieved via the electrolysis of a hydrolyzed sol containing the biomolecules to initiate the poly-condensation of silica precursors upon electrochemically induced pH increase at the electrode/solution interface. DSDH was found to be very sensitive to the silica gel environment and the addition of a positively-charged polyelectrolyte was necessary to ensure effective operational behavior of the biomolecules. The composition of the sol and the conditions for electrolysis have been optimized with respect to the intensity of the electrochemical response to D-sorbitol oxidation. The K{sub m} of DSDH in the electrodeposited film was in the range of 3 mM, slightly better than the value determined biochemically in solution (6.5 mM). The co-immobilization of DSDH and diaphorase in this way led on the one hand to the possible reduction of NAD{sup +} to NADH (simultaneously to D-sorbitol oxidation) and on the other hand to the safe re-oxidation of the co-factor using a mediator (ferrocenedimethanol) as electron relay. The bioelectrocatalytic response looks promising for electro-enzymatic applications. To support this idea, the EAD of sol-gel bio-composite has been extended to macroporous electrodes displaying a much bigger electroactive surface area.

  16. Electronic and optical device applications of hollow cathode plasma assisted atomic layer deposition based GaN thin films

    Energy Technology Data Exchange (ETDEWEB)

    Bolat, Sami, E-mail: bolat@ee.bilkent.edu.tr; Tekcan, Burak [Department of Electrical and Electronics Engineering, Bilkent University, 06800, Ankara, Turkey and UNAM, National Nanotechnology Research Center, Bilkent University, 06800, Ankara (Turkey); Ozgit-Akgun, Cagla; Biyikli, Necmi [UNAM, National Nanotechnology Research Center, Bilkent University, 06800, Ankara, Turkey and Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara (Turkey); Okyay, Ali Kemal, E-mail: aokyay@ee.bilkent.edu.tr [Department of Electrical and Electronics Engineering, Bilkent University, 06800, Ankara (Turkey); UNAM, National Nanotechnology Research Center, Bilkent University, 06800, Ankara (Turkey); Institute of Materials Science and Nanotechnology, Bilkent University, 06800, Ankara (Turkey)

    2015-01-15

    Electronic and optoelectronic devices, namely, thin film transistors (TFTs) and metal–semiconductor–metal (MSM) photodetectors, based on GaN films grown by hollow cathode plasma-assisted atomic layer deposition (PA-ALD) are demonstrated. Resistivity of GaN thin films and metal-GaN contact resistance are investigated as a function of annealing temperature. Effect of the plasma gas and postmetallization annealing on the performances of the TFTs as well as the effect of the annealing on the performance of MSM photodetectors are studied. Dark current to voltage and responsivity behavior of MSM devices are investigated as well. TFTs with the N{sub 2}/H{sub 2} PA-ALD based GaN channels are observed to have improved stability and transfer characteristics with respect to NH{sub 3} PA-ALD based transistors. Dark current of the MSM photodetectors is suppressed strongly after high-temperature annealing in N{sub 2}:H{sub 2} ambient.

  17. Growth and characterization of large, high quality single crystal diamond substrates via microwave plasma assisted chemical vapor deposition

    Science.gov (United States)

    Nad, Shreya

    Single crystal diamond (SCD) substrates can be utilized in a wide range of applications. Important issues in the chemical vapor deposition (CVD) of such substrates include: shrinking of the SCD substrate area, stress and cracking, high defect density and hence low electronic quality and low optical quality due to high nitrogen impurities. The primary objective of this thesis is to begin to address these issues and to find possible solutions for enhancing the substrate dimensions and simultaneously improving the quality of the grown substrates. The deposition of SCD substrates is carried out in a microwave cavity plasma reactor via the microwave plasma assisted chemical vapor deposition technique. The operation of the reactor was first optimized to determine the safe and efficient operating regime. By adjusting the matching of the reactor cavity with the help of four internal tuning length variables, the system was further matched to operate at a maximum overall microwave coupling efficiency of ˜ 98%. Even with adjustments in the substrate holder position, the reactor remains well matched with a coupling efficiency of ˜ 95% indicating good experimental performance over a wide range of operating conditions. SCD substrates were synthesized at a high pressure of 240 Torr and with a high absorbed power density of 500 W/cm3. To counter the issue of shrinking substrate size during growth, the effect of different substrate holder designs was studied. An increase in the substrate dimensions (1.23 -- 2.5 times) after growth was achieved when the sides of the seeds were shielded from the intense microwave electromagnetic fields in a pocket holder design. Using such pocket holders, high growth rates of 16 -- 32 mum/hr were obtained for growth times of 8 -- 72 hours. The polycrystalline diamond rim deposition was minimized/eliminated from these growth runs, hence successfully enlarging the substrate size. Several synthesized CVD SCD substrates were laser cut and separated

  18. On the influence of DC electric fields on the aerosol assisted chemical vapor deposition growth of photoactive titanium dioxide thin films.

    Science.gov (United States)

    Romero, Luz; Binions, Russell

    2013-11-01

    Titanium dioxide thin films were deposited on fluorine doped tin oxide glass substrate from the electric field assisted aerosol chemical vapor deposition (EACVD) reaction of titanium isopropoxide (TTIP, Ti(OC3H7)4) in toluene on glass substrates at a temperature of 450 °C. DC electric fields were generated by applying a potential difference between the electrodes of the transparent coated oxide coated glass substrates during the deposition. The deposited films were characterized using scanning electron microscopy, X-ray diffraction, atomic force microscopy, Raman spectroscopy, and UV-vis spectroscopy. The photoactivity and hydrophilicity of the deposited films were also analyzed using a dye-ink test and water-contact angle measurements. The characterization work revealed that the incorporation of DC electric fields produced significant reproducible changes in the film microstructure, preferred crystallographic orientation, roughness, and film thickness. Photocatalytic activity was calculated from the half-time (t1/2) or time taken to degrade 50% of the initial resazurin dye concentration. A large improvement in photocatalytic activity was observed for films deposited using an electric field with a strong orientation in the (004) direction (t1/2 17 min) as compared to a film deposited with no electric field (t1/2 40 min). PMID:24160408

  19. Physical and tribological properties of a-Si1-xCx:H coatings prepared by r.f. plama-assisted chemical vapour deposition

    International Nuclear Information System (INIS)

    A-Si1-xCx:H films deposited by r.f. plasma-assisted chemical vapour deposition were studied as a function of their composition. The friction and wear properties were investigated with the help of a conventional ball-on-disc apparatus. These results are correlated with chemical (Si/C atomic ratio) and structural (Raman and infrared spectroscopy) properties. The friction coefficient in a humid ambient atmosphere changes markedly with the carbon fraction and reaches a value as low as 0.05 for coatings with 70 to 90 at.% C. The carbon-rich films consist of diamond-like carbon with silicon. (orig.)

  20. The role of hydrogen in oxygen-assisted chemical vapor deposition growth of millimeter-sized graphene single crystals

    Science.gov (United States)

    Zhao, Pei; Cheng, Yu; Zhao, Dongchen; Yin, Kun; Zhang, Xuewei; Song, Meng; Yin, Shaoqian; Song, Yenan; Wang, Peng; Wang, Miao; Xia, Yang; Wang, Hongtao

    2016-03-01

    Involving oxygen in the traditional chemical vapor deposition (CVD) process has proven a promising approach to achieve large-scale graphene single crystals (GSCs), but its many relevant fundamental aspects are still not fully understood. Here we report a systematic study on the role of hydrogen in the growth of millimeter-sized GSCs using enclosure-like Cu structures via the oxygen-assisted CVD process. Results show that GSCs have different first layer growth behaviors on the inside and outside surfaces of a Cu enclosure when the H2 environment is varied, and these behaviors will consequently and strongly influence the adlayer formation in these GSCs, leading to two entirely different growth modes. Low H2 partial pressure (PH2) tends to result in fast growth of dendritically shaped GSCs with multiple small adlayers, but high PH2 can modify the GSC shape into hexagons with single large adlayer nuclei. This difference of adlayers is attributed to the different C diffusion paths determined by the shapes of their host GSCs. On the basis of these observations, we developed an isothermal two-step method to obtain GSCs with significantly improved growth rate and sample quality, in which low PH2 is first set to accelerate the growth rate followed by high PH2 to restrict the adlayer nuclei. Our results prove that the growth of GSCs can reach a reasonable optimization between their growth rates and sample quality by simply adjusting the CVD H2 environment, which we believe will lead to more improvements in graphene synthesis and fundamental insight into the related growth mechanisms.Involving oxygen in the traditional chemical vapor deposition (CVD) process has proven a promising approach to achieve large-scale graphene single crystals (GSCs), but its many relevant fundamental aspects are still not fully understood. Here we report a systematic study on the role of hydrogen in the growth of millimeter-sized GSCs using enclosure-like Cu structures via the oxygen-assisted CVD

  1. Dense CdS thin films on fluorine-doped tin oxide coated glass by high-rate microreactor-assisted solution deposition

    Energy Technology Data Exchange (ETDEWEB)

    Su, Yu-Wei, E-mail: suyuweiwayne@gmail.com [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Ramprasad, Sudhir [Energy Processes and Materials Division, Pacific Northwest National Laboratory, Corvallis, OR 9730 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Han, Seung-Yeol; Wang, Wei [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Ryu, Si-Ok [School of Display and Chemical Engineering, Yeungnam University, 214-1 Dae-dong, Gyeonsan, Gyeongbuk 712-749 (Korea, Republic of); Palo, Daniel R. [Barr Engineering Co., Hibbing, MN 55747 (United States); Paul, Brian K. [School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Chang, Chih-hung [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States)

    2013-04-01

    Continuous microreactor-assisted solution deposition is demonstrated for the deposition of CdS thin films on fluorine-doped tin oxide (FTO) coated glass. The continuous flow system consists of a microscale T-junction micromixer with the co-axial water circulation heat exchanger to control the reacting chemical flux and optimize the heterogeneous surface reaction. Dense, high quality nanocrystallite CdS thin films were deposited at an average rate of 25.2 nm/min, which is significantly higher than the reported growth rate from typical batch chemical bath deposition process. Focused-ion-beam was used for transmission electron microscopy specimen preparation to characterize the interfacial microstructure of CdS and FTO layers. The band gap was determined at 2.44 eV by UV–vis absorption spectroscopy. X-ray photon spectroscopy shows the binding energies of Cd 3d{sub 3/2}, Cd 3d{sub 5/2}, S 2P{sub 3/2} and S 2P{sub 1/2} at 411.7 eV, 404.8 eV, 162.1 eV and 163.4 eV, respectively. - Highlights: ► CdS films deposited using continuous microreactor-assisted solution deposition (MASD) ► Dense nanocrystallite CdS films can be reached at a rate of 25.2 [nm/min]. ► MASD can approach higher film growth rate than conventional chemical bath deposition.

  2. Mechanical and electrochemical properties of ultrasonic-assisted electroless deposition of Ni–B–TiO{sub 2} composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Niksefat, Vahid; Ghorbani, Mohammad, E-mail: ghorbani@sharif.edu

    2015-06-05

    Highlights: • Ni–B–TiO{sub 2} coatings developed by ultrasonic-assisted electroless method. • Titania improves corrosion resistance and hardness of the Ni–B as-plated coatings. • Titania increases the surface film resistance of the Ni–B as-plated coatings. - Abstract: Nickel–Boron–Titania (Ni–B–TiO{sub 2}) composite coatings were successfully obtained on mild steel (St-37) by simultaneous electroless deposition. TiO{sub 2} particles were dispersed in a suspension by ultrasonic irradiation. The surface morphology, particle size, elemental composition and phase analysis of the coatings were characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP) and X-ray diffraction (XRD). The hardness and friction coefficient of as- plated and heat treated Ni–B and Ni–B–TiO{sub 2} composite coatings were determined by Vickers diamond indentation and indentation scratch tests and compared with Ni–B coatings. As a result, the hardness (1263 HV) of the as-plated Ni–B–TiO{sub 2} coatings was improved significantly. In addition, the corrosion resistance behavior of the as-plated and heat treated Ni–B and Ni–B–TiO{sub 2} coatings were analyzed by anodic polarization and electrochemical impedance spectroscopic (EIS) studies in a 3.5 wt.% NaCl solution. The as-plated composite coatings (Ni–B–TiO{sub 2}) exhibited enhanced corrosion resistance (0.2 μA/cm{sup 2}) property over Ni–B coatings.

  3. Observation of low resistivity and high mobility in Ga doped ZnO thin films grown by buffer assisted pulsed laser deposition

    International Nuclear Information System (INIS)

    Highlights: • Ga doped ZnO thin films were grown using buffer assisted pulsed laser deposition. • Lowest resistivity ∼5.1 × 10−5 Ω cm with a mobility of ∼41.9 cm2/V s was observed. • Buffer assisted growth methodology maintains relatively good crystalline quality. • This plays a key role in decreasing the resistivity of to the aforementioned value. • This resistivity value, to the best of our knowledge is the lowest so far in ZnO. - Abstract: We have grown Ga doped ZnO (GZO) thin films at moderate temperatures with Ga concentrations in the range varying from 0.25 to 3 at.% on sapphire substrates using buffer assisted pulsed laser deposition. Room temperature resistivity measured was ∼5.1 × 10−5 Ω cm with a electron mobility of ∼41.9 cm2/V s for an optimum Ga concentration of ∼0.75 at.% in the GZO films. Buffer assisted growth methodology maintains relatively good crystalline quality of the GZO thin films, thereby improving the electron mobility even at high dopant concentrations. This plays a key role in decreasing the resistivity of GZO films to the aforementioned value, which to the best of our knowledge is the lowest so far. These highly conducting GZO thin films with good mobility are potential candidates for transparent conducting oxide (TCO) applications in various optoelectronic devices

  4. Performance Improvement of Microcrystalline p-SiC/i-Si/n-Si Thin Film Solar Cells by Using Laser-Assisted Plasma Enhanced Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    Hsin-Ying Lee

    2014-01-01

    Full Text Available The microcrystalline p-SiC/i-Si/n-Si thin film solar cells treated with hydrogen plasma were fabricated at low temperature using a CO2 laser-assisted plasma enhanced chemical vapor deposition (LAPECVD system. According to the micro-Raman results, the i-Si films shifted from 482 cm−1 to 512 cm−1 as the assisting laser power increased from 0 W to 80 W, which indicated a gradual transformation from amorphous to crystalline Si. From X-ray diffraction (XRD results, the microcrystalline i-Si films with (111, (220, and (311 diffraction were obtained. Compared with the Si-based thin film solar cells deposited without laser assistance, the short-circuit current density and the power conversion efficiency of the solar cells with assisting laser power of 80 W were improved from 14.38 mA/cm2 to 18.16 mA/cm2 and from 6.89% to 8.58%, respectively.

  5. Electroless copper on refractory and noble metal substrates with an ultra-thin plasma-assisted atomic layer deposited palladium layer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Soon [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Kim, Hyung-Il [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Cho, Joong-Hee [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Seo, Hyung-Kee [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Dar, M.A. [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Shin, Hyung-Shik [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Ten Eyck, Gregory A. [Department of Physics, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Lu, Toh-Ming [Department of Physics, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Senkevich, Jay J. [Brewer Science Inc., Rolla, MO 65401 (United States)]. E-mail: jsenkevich@brewerscience.com

    2006-02-25

    Electroless Cu was investigated on refractory metal, W and TaN {sub X}, and Ir noble metal substrates with a plasma-assisted atomic layer deposited palladium layer for the potential back-end-of-the-line (BEOL) metallization of advanced integrated devices. The sodium and potassium-free Cu electroless bath consisted of: ethylenediamine tetraacetic acid (EDTA) as a chelating agent, glyoxylic acid as a reducing agent, and additional chemicals such as polyethylene glycol, 2,2'-dipyridine and RE-610 as surfactant, stabilizer and wetting agent respectively. The growth and chemical characterization of the Cu films was carried out with a field emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), and Rutherford backscattering spectrometry (RBS). Group VIII metals such as Pt, Pd, etc., are stable in the electroless bath and catalytic towards the oxidation of glyoxylic acid and therefore work well for the electroless deposition of Cu. From RBS analysis, the amount of carbon and oxygen in Cu films were less than 1-3%. The Cu films were electroless deposited at 45-50 deg. C on patterned tantalum nitride with plasma-assisted atomic layer deposited (PA-ALD) Pd as a catalytic layer. Electroless Cu trench fill was successful with ultrasonic vibration, RE-610, and lowering the temperature to 45-50 deg. C on TaN {sub X} with the PA-ALD Pd catalytic layer.

  6. Thin films of tin(II) sulphide (SnS) by aerosol-assisted chemical vapour deposition (AACVD) using tin(II) dithiocarbamates as single-source precursors

    Science.gov (United States)

    Kevin, Punarja; Lewis, David J.; Raftery, James; Azad Malik, M.; O'Brien, Paul

    2015-04-01

    The synthesis of the asymmetric dithiocarbamates of tin(II) with the formula [Sn(S2CNRR')2] (where R=Et, R'=n-Bu (1); R=Me, R'=n-Bu (2); R=R'=Et (3)) and their use for the deposition of SnS thin films by aerosol-assisted chemical vapour deposition (AACVD) is described. The effects of temperature and the concentration of the precursors on deposition were investigated. The stoichiometry of SnS was best at higher concentrations of precursors (250 mM) and at 450 °C. The direct electronic band gap of the SnS produced by this method was estimated from optical absorbance measurements as 1.2 eV. The composition of films was confirmed by powder X-ray diffraction (p-XRD) and energy dispersive analysis of X-rays (EDAX) spectroscopy.

  7. Effects of room-temperature tensile fatigue on critical current and n-value of IBAD-MOCVD YBa2Cu3O7-x /Hastelloy coated conductor

    Science.gov (United States)

    Rogers, Samuel; Kan Chan, Wan; Schwartz, Justin

    2016-08-01

    REBa2Cu3O7-x (REBCO) coated conductors potentially enable a multitude of superconducting applications, over a wide range of operating temperatures and magnetic fields, including high-field magnets, energy storage devices, motors, generators, and power transmission systems (Zhang et al 2013 IEEE Trans. Appl. Supercond. 23 5700704). Many of these are AC applications and thus the fatigue properties may be limiting (Vincent et al 2013 IEEE Trans. Appl. Supercond. 23 5700805). Previous electromechanical studies have determined the performance of REBCO conductors under single cycle loads (Barth et al 2015 Supercond. Sci. Technol. 28 045011), but an understanding of the fatigue properties is lacking. Here the fatigue behavior of commercial ion beam assisted deposition-metal organic chemical vapor deposition REBCO conductors on Hastelloy substrates is reported for axial tensile strains up to 0.5% and up to 100 000 cycles. Failure mechanisms are investigated via microstructural studies. Results show that REBCO conductors retained I c(ɛ)/I c0 = 0.9 for 10 000 cycles at ɛ = 0.35% and ɛ = 0.45% strain, and ɛ = 0.5% for 100 cycles. The main cause of fatigue degradation in REBCO conductors is crack propagation that initiates at the slitting defects that result from the manufacturing process.

  8. Deposição e perdas da calda em feijoeiro em aplicação com assistência de ar na barra pulverizadora Spray deposition and spray loss using air-assistance boom on bean plants

    Directory of Open Access Journals (Sweden)

    Carlos Gilberto Raetano

    2004-01-01

    Full Text Available Com o objetivo de avaliar a influência da assistência de ar na deposição da calda de pulverização, em plantas de feijoeiro (Phaseolus vulgaris aos 26 dias após a emergência (DAE, com pontas de pulverização de jato cônico vazio (JA-0,5 e JA-1 e jato plano (AXI-110015, e volumes de calda, foi realizado um experimento em delineamento inteiramente casualizado, utilizando como traçador o íon cobre. Alvos coletores (papel de filtro com 3 x 3 cm foram afixados nas superfícies adaxial e abaxial de folíolos posicionados nas partes superior e inferior das plantas. Para aplicar a solução traçadora, utilizou-se pulverizador com barras de 14 metros, com e sem assistência de ar, volumes de 60 e 100 L.ha-1, e velocidade do ar correspondente a 50% da rotação máxima do ventilador. Após a aplicação, os coletores foram lavados individualmente em solução extratora de ácido nítrico a 1,0 mol.L-1, e a quantificação dos depósitos através de espectrofotometria. A assistência de ar não influenciou na deposição da calda tanto a 60 quanto a 100 L.ha-1. O maior volume proporcionou maiores depósitos, sendo constatadas elevadas perdas para o solo (mais de 60%.Aiming to evaluate the effect of air-assistance in spray deposition on bean plants (Phaseolus vulgaris with hollow nozzles (JA-0,5 and JA-1 and flat fan nozzle type (AXI-110015, and volume rates by air-assisted and non-assisted sprayers, a completely randomized experiment was carried out using copper ion as a tracer to the evaluation of the deposits. At 26 days after emergence, artificial targets were positioned on the upper and under-side of the leaflets, on the top and bottom parts of the same plants under spray boom. For the application of tracer solution it was used a fourteen meter boom sprayer with and without air-assistance at 60 and 100 L.ha-1 of volume rates. The air flow was 50% of the maximum fan rotation. After application, targets were individually washed with an

  9. Influence of alkali metals (Na, Li, Rb) on the performance of electrostatic spray-assisted vapor deposited Cu2ZnSn(S,Se)4 solar cells

    Science.gov (United States)

    Altamura, Giovanni; Wang, Mingqing; Choy, Kwang-Leong

    2016-02-01

    Electrostatic Spray-Assisted Vapor Deposition (ESAVD) is a non-vacuum and cost-effective method to deposit metal oxide, various sulphide and chalcogenide at large scale. In this work, ESAVD was used to deposit Cu2ZnSn(S1-xSex)4 (CZTSSe) absorber. Different alkali metals like Na, Li and Rb were incorporated in CZTSSe compounds to further improve the photovoltaic performances of related devices. In addition, to the best of our knowledge, no experimental study has been carried out to test the effect of Li and Rb incorporation in CZTSSe solar cells. X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and glow discharge spectroscopy have been used to characterize the phase purity, morphology and composition of as-deposited CZTSSe thin films. Photovoltaic properties of the resulting devices were determined by completing the solar cells as follows: Mo/CZTSSe/CdS/i-ZnO/Al:ZnO/Ni/Al. The results showed that Li, Na and Rb incorporation can increase power conversion efficiency of CZTS devices up to 5.5%. The introduction of a thiourea treatment, has improved the quality of the absorber|buffer interface, pushed the device efficiency up to 6.3% which is at the moment the best reported result for ESAVD deposited CZTSSe solar cells.

  10. Ecofriendly and Nonvacuum Electrostatic Spray-Assisted Vapor Deposition of Cu(In,Ga)(S,Se)2 Thin Film Solar Cells.

    Science.gov (United States)

    Hossain, Md Anower; Wang, Mingqing; Choy, Kwang-Leong

    2015-10-14

    Chalcopyrite Cu(In,Ga)(S,Se)2 (CIGSSe) thin films have been deposited by a novel, nonvacuum, and cost-effective electrostatic spray-assisted vapor deposition (ESAVD) method. The generation of a fine aerosol of precursor solution, and their controlled deposition onto a molybdenum substrate, results in adherent, dense, and uniform Cu(In,Ga)S2 (CIGS) films. This is an essential tool to keep the interfacial area of thin film solar cells to a minimum value for efficient charge separation as it helps to achieve the desired surface smoothness uniformity for subsequent cadmium sulfide and window layer deposition. This nonvacuum aerosol based approach for making the CIGSSe film uses environmentally benign precursor solution, and it is cheaper for producing solar cells than that of the vacuum-based thin film solar technology. An optimized CIGSSe thin film solar cell with a device configuration of molybdenum-coated soda-lime glass substrate/CIGSSe/CdS/i-ZnO/AZO shows the photovoltaic (j-V) characteristics of Voc=0.518 V, jsc=28.79 mA cm(-2), fill factor=64.02%, and a promising power conversion efficiency of η=9.55% under simulated AM 1.5 100 mW cm(-2) illuminations, without the use of an antireflection layer. This demonstrates the potential of ESAVD deposition as a promising alternative approach for making thin film CIGSSe solar cells at a lower cost. PMID:26390182

  11. Sub-micro a-C:H patterning of silicon surfaces assisted by atmospheric-pressure plasma-enhanced chemical vapor deposition

    Science.gov (United States)

    Boileau, Alexis; Gries, Thomas; Noël, Cédric; Perito Cardoso, Rodrigo; Belmonte, Thierry

    2016-11-01

    Micro and nano-patterning of surfaces is an increasingly popular challenge in the field of the miniaturization of devices assembled via top-down approaches. This study demonstrates the possibility of depositing sub-micrometric localized coatings—spots, lines or even more complex shapes—made of amorphous hydrogenated carbon (a-C:H) thanks to a moving XY stage. Deposition was performed on silicon substrates using chemical vapor deposition assisted by an argon atmospheric-pressure plasma jet. Acetylene was injected into the post-discharge region as a precursor by means of a glass capillary with a sub-micrometric diameter. A parametric study was carried out to study the influence of the geometric configurations (capillary diameter and capillary-plasma distance) on the deposited coating. Thus, the patterns formed were investigated by scanning electron microscopy and atomic force microscopy. Furthermore, the chemical composition of large coated areas was investigated by Fourier transform infrared spectroscopy according to the chosen atmospheric environment. The observed chemical bonds show that reactions of the gaseous precursor in the discharge region and both chemical and morphological stability of the patterns after treatment are strongly dependent on the surrounding gas. Various sub-micrometric a-C:H shapes were successfully deposited under controlled atmospheric conditions using argon as inerting gas. Overall, this new process of micro-scale additive manufacturing by atmospheric plasma offers unusually high-resolution at low cost.

  12. Bioactivity and osteogenic cell response of TiO{sub 2} nanotubes coupled with nanoscale calcium phosphate via ultrasonification-assisted electrochemical deposition

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jianyu, E-mail: chenjianyu-b2@163.com [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Zhang, Zhiguang, E-mail: 13580393430@163.com [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Ouyang, Jianglin; Chen, Xianshuai [Guangzhou Institute of Advanced Technology, Chinese Academy of Science, Guangzhou 511458 (China); Xu, Zhewu [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Sun, Xuetong [Guangzhou Institute of Advanced Technology, Chinese Academy of Science, Guangzhou 511458 (China)

    2014-06-01

    Ultrasonification-assisted electrochemical deposition was used to introduce nanoscale calcium phosphate (CaP) into well-ordered TiO{sub 2} nanotube arrays (NTA) fabricated by anodic oxidation. Field emission scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and a drop-shape analysis system were used to investigate the morphology, constituent components and hydrophilicity of the nanostructured CaP/NTA surface. Bioactivity and osteogenic cell response were also characterized by hydroxyapatite (HA) formation tests, protein adsorption tests, and in vitro preosteoblast culture experiments. Abundant acicular nanoscale calcium phosphate was successfully deposited on the inner and outer walls of the nanotubes. After immersion in simulated body fluid, increased hydroxyapatite formation was apparent on the surface of TiO{sub 2} nanotubes coupled with nanoscale CaP when compared to simple nanotube structures and polished titanium. The CaP/NTA surface also adsorbed a greater amount of protein after being exposed to bovine serum albumin solution. During cell culture experiments, the preosteoblasts exhibited enhanced cellular adhesion, proliferation, and differentiation on the CaP/NTA surfaces. The results demonstrate that the introduction of nanoscale calcium phosphate into self-organized TiO{sub 2} nanotubes via a straightforward ultrasonification-assisted deposition technique enhances the bioactivity and osteogenic cell response, owing to the combined effects of the nanostructured surface topography, chemical composition, and hydrophilicity.

  13. Preparation of ZnO/Al2O3 catalysts by using atomic layer deposition for plasma-assisted non-oxidative methane coupling

    Science.gov (United States)

    Jeong, Myung-Geun; Kim, Young Dok; Park, Sunyoung; Kasinathan, Palraj; Hwang, Young Kyu; Chang, Jong-San; Park, Yong-Ki

    2016-05-01

    We prepared a ZnO/mesoporous Al2O3-shell/core structure by using atomic layer deposition (ALD) of ZnO on commercially-available mesoporous Al2O3. We used various analysis techniques such as scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, inductively coupled plasma-atomic emission spectroscopy, and surface area and pore size analyses based on nitrogen isotherm data. A 200 nm-thick slab of mesoporous Al2O3 particles was decorated by ZnO upon ALD deposition, whereas the inner part of the Al2O3 particle was free of ZnO. We evaluated the catalytic activity of the bare and the ZnO-covered Al2O3 for plasma-assisted nonoxidative coupling of methane. The catalytic behavior was shown to be sensitive to the amount of ZnO deposited. Particularly, 40-cycled ZnO/Al2O3 showed an enhanced selectivity to the olefin product with almost the same CH4 conversion as that of bare Al2O3. Preparation of the shell/core structure by using ALD can be an interesting strategy for finding highly-efficient catalysts in a plasma-assisted catalytic reaction.

  14. Composite films prepared by plasma ion-assisted deposition (IAD) for design and fabrication of antireflection coatings in visible and near-infrared spectral regions

    Science.gov (United States)

    Tsai, Rung-Ywan; Ho, Fang C.

    1994-11-01

    Ion-assisted deposition (IAD) processes configured with a well-controlled plasma source at the center base of a vacuum chamber, which accommodates two independent e-gun sources, is used to deposition TiO2MgF2 and TiO2-SiO2 composite films of selected component ratios. Films prepared by this technology are found durable, uniform, and nonabsorbing in visible and near-IR regions. Single- and multilayer antireflection coatings with refractive index from 1.38 to 2.36 at (lambda) equals 550 nm are presented. Methods of enhancement in optical performance of these coatings are studied. The advantages of AR coatings formed by TiO2-MgF2 composite films over those similar systems consisting of TiO2-SiO2 composite films in both visible and near-IR regions are also presented.

  15. Preparation of high-quality hydrogenated amorphous silicon film with a new microwave electron cyclotron resonance chemical vapour deposition system assisted with hot wire

    Institute of Scientific and Technical Information of China (English)

    Zhu Xiu-Hong; Chen Guang-Hua; Yin Sheng-Yi; Rong Yan-Dong; Zhang Wen-Li; Hu Yue-Hui

    2005-01-01

    The preparation of high-quality hydrogenated amorphous silicon (a-Si:H) film with a new microwave electron cyclotron resonance-chemical vapour deposition (MWECR-CVD) system assisted with hot wire is presented. In this system the hot wire plays an important role in perfecting the microstructure as well as improving the stability and the optoelectronic properties of the a-Si:H film. The experimental results indicate that in the microstructure of the a-Si:H film, the concentration of dihydride is decreased and a trace of microcrystalline occurs, which is useful to improve its stability, and that in the optoelectronic properties of the a-Si:H film, the deposition rate reaches above 2.0nm/s and the photosensitivity increases up to 4.71× 105.

  16. Effect of surfactants on the morphology of FeSe films fabricated from a single source precursor by aerosol assisted chemical vapour deposition

    Indian Academy of Sciences (India)

    Raja Azadar Hussain; Amin Badshah; Naghma Haider; Malik Dilshad Khan; Bhajan Lal

    2015-03-01

    This article presents the fabrication of FeSe thin films from a single source precursor namely (1-(2-fluorobenzoyl)-3-(4-ferrocenyl-3-methylphenyl)selenourea (MeP2F)) by aerosol assisted chemical vapour deposition (AACVD). All the films were prepared via similar experimental conditions (temperature, flow rate, concentration, solvent system and reactor type) except the use of three different concentrations of two different surfactants i.e., triton and span. Seven thin films were characterized with PXRD, SEM, AFM, EDS and EDS mapping. The mechanism of the interaction of surfactant with MeP2F was determined with cyclic voltammetry (CV) and UV-Vis spectroscopy.

  17. Vertical La0.7Ca0.3MnO3 nanorods tailored by high magnetic field assisted pulsed laser deposition

    OpenAIRE

    Kejun Zhang; Jianming Dai; Xuebin Zhu; Xiaoguang Zhu; Xuzhong Zuo; Peng Zhang; Ling Hu; Wenjian Lu; Wenhai Song; Zhigao Sheng; Wenbin Wu; Yuping Sun; Youwei Du

    2016-01-01

    La0.7Ca0.3MnO3 (LCMO) thin films on (LaAlO3)0.3(Sr2AlTaO6)0.7 (001) [LSAT (001)] single crystal substrates have been prepared by high magnetic field assisted pulsed laser deposition (HMF-PLD) developed by ourselves. Uniformly sized and vertically aligned nanorod structures can be obtained under an applied high magnetic field above 5 T, and the dimension size of the nanorods can be manipulated by varying the applied magnetic field. It is found that the magnetic anisotropy is strongly correlate...

  18. Composition and properties of surface of Me/Si systems, prepared by deposition of Ti and Co thin films assisted by self-ion

    International Nuclear Information System (INIS)

    In this paper a composite structure, topography, wettability and nanohardness of a surface (100) Si modified by means of ion-assisted deposition of coatings in conditions of a self-irradiation are discussed. Rutherford backscattering of He+ ions and computer program RUMP were applied to investigate a composition of surface. It is established, that coatings include atoms of metal, hydrogen, carbon, oxygen, silicon. The nanoindentation data from coated systems were used for calculation of the hardness and elastic modulus using load and displacement sensing indentation experiments. Atomic Force Microscopy surface observations were used to investigate the topography of modified surfaces. Hydrophilicity was measured by means of the contact angle measurement technique. (authors)

  19. Growth of thick La2Zr2O7 buffer layers for coated conductors by polymer-assisted chemical solution deposition

    International Nuclear Information System (INIS)

    Highlights: • We develops a low-cost and high-efficient technology of fabricating LZO buffer layers. • Sufficient thickness LZO buffer layers have been obtained on NiW (2 0 0) alloy substrate. • Highly biaxially textured YBCO thin film has been deposited on LZO/NiW. - Abstract: La2Zr2O7 (LZO) epitaxial films have been deposited on LaAlO3 (LAO) (1 0 0) single-crystal surface and bi-axially textured NiW (2 0 0) alloy substrate by polymer-assisted chemical solution deposition, and afterwards studied with XRD, SEM and AFM approaches. Highly in-plane and out-of-plane oriented, dense, smooth, crack free and with a sufficient thickness (>240 nm) LZO buffer layers have been obtained on LAO (1 0 0) single-crystal surface; The films deposited on NiW (2 0 0) alloy substrate are also found with high degree in-plane and out-of-plane texturing, good density with pin-hole-free, micro-crack-free nature and a thickness of 300 nm. Highly epitaxial 500 nm thick YBa2Cu3O7−x (YBCO) thin film exhibits the self-field critical current density (Jc) reached 1.3 MA/cm2 at 77 K .These results demonstrate the LZO epi-films obtained with current techniques have potential to be a buffer layer for REBCO coated conductors

  20. Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor

    International Nuclear Information System (INIS)

    In this work, the authors developed hot-wire assisted atomic layer deposition (HWALD) to deposit tungsten (W) with a tungsten filament heated up to 1700–2000 °C. Atomic hydrogen (at-H) was generated by dissociation of molecular hydrogen (H2), which reacted with WF6 at the substrate to deposit W. The growth behavior was monitored in real time by an in situ spectroscopic ellipsometer. In this work, the authors compare samples with tungsten grown by either HWALD or chemical vapor deposition (CVD) in terms of growth kinetics and properties. For CVD, the samples were made in a mixture of WF6 and molecular or atomic hydrogen. Resistivity of the WF6-H2 CVD layers was 20 μΩ·cm, whereas for the WF6-at-H-CVD layers, it was 28 μΩ·cm. Interestingly, the resistivity was as high as 100 μΩ·cm for the HWALD films, although the tungsten films were 99% pure according to x-ray photoelectron spectroscopy. X-ray diffraction reveals that the HWALD W was crystallized as β-W, whereas both CVD films were in the α-W phase

  1. Study of temperature dependence and angular distribution of poly(9,9-dioctylfluorene) polymer films deposited by matrix-assisted pulsed laser evaporation (MAPLE)

    International Nuclear Information System (INIS)

    Poly(9,9-dioctylfluorene) (PFO) polymer films were deposited by matrix-assisted pulsed laser evaporation (MAPLE) technique. The polymer was diluted (0.5 wt%) in tetrahydrofuran and, once cooled to liquid nitrogen temperature, it was irradiated with a KrF excimer laser. 10,000 laser pulses were used to deposit PFO films on Si substrates at different temperatures (-16, 30, 50 and 70 deg. C). One PFO film was deposited with 16,000 laser pulses at a substrate temperature of 50 deg. C. The morphology, optical and structural properties of the films were investigated by SEM, AFM, PL and FTIR spectroscopy. SEM inspection showed different characteristic features on the film surface, like deflated balloons, droplets and entangled polymer filaments. The roughness of the films was, at least partially, controlled by substrate heating, which however had the effect to reduce the deposition rate. The increase of the laser pulse number modified the target composition and increased the surface roughness. The angular distribution of the material ejected from the target confirmed the forward ejection of the target material. PFO films presented negligible modification of the chemical structure respect to the bulk material.

  2. Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Mengdi, E-mail: M.Yang@utwente.nl; Aarnink, Antonius A. I.; Kovalgin, Alexey Y.; Gravesteijn, Dirk J.; Wolters, Rob A. M.; Schmitz, Jurriaan [MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)

    2016-01-15

    In this work, the authors developed hot-wire assisted atomic layer deposition (HWALD) to deposit tungsten (W) with a tungsten filament heated up to 1700–2000 °C. Atomic hydrogen (at-H) was generated by dissociation of molecular hydrogen (H{sub 2}), which reacted with WF{sub 6} at the substrate to deposit W. The growth behavior was monitored in real time by an in situ spectroscopic ellipsometer. In this work, the authors compare samples with tungsten grown by either HWALD or chemical vapor deposition (CVD) in terms of growth kinetics and properties. For CVD, the samples were made in a mixture of WF{sub 6} and molecular or atomic hydrogen. Resistivity of the WF{sub 6}-H{sub 2} CVD layers was 20 μΩ·cm, whereas for the WF{sub 6}-at-H-CVD layers, it was 28 μΩ·cm. Interestingly, the resistivity was as high as 100 μΩ·cm for the HWALD films, although the tungsten films were 99% pure according to x-ray photoelectron spectroscopy. X-ray diffraction reveals that the HWALD W was crystallized as β-W, whereas both CVD films were in the α-W phase.

  3. Electrochemically assisted deposition of hydroxyapatite on Ti6Al4V substrates covered by CVD diamond films - Coating characterization and first cell biological results.

    Science.gov (United States)

    Strąkowska, Paulina; Beutner, René; Gnyba, Marcin; Zielinski, Andrzej; Scharnweber, Dieter

    2016-02-01

    Although titanium and its alloys are widely used as implant material for orthopedic and dental applications they show only limited corrosion stability and osseointegration in different cases. The aim of the presented research was to develop and characterize a novel surface modification system from a thin diamond base layer and a hydroxyapatite (HAp) top coating deposited on the alloy Ti6Al4V widely used for implants in contact with bone. This coating system is expected to improve both the long-term corrosion behavior and the biocompatibility and bioactivity of respective surfaces. The diamond base films were obtained by Microwave Plasma Assisted Chemical Vapor Deposition (MW-PACVD); the HAp coatings were formed in aqueous solutions by electrochemically assisted deposition (ECAD) at varying polarization parameters. Scanning electron microscopy (SEM), Raman microscopy, and electrical conductivity measurements were applied to characterize the generated surface states; the calcium phosphate coatings were additionally chemically analyzed for their composition. The biological properties of the coating system were assessed using hMSC cells analyzing for cell adhesion, proliferation, and osteogenic differentiation. Varying MW-PACVD process conditions resulted in composite coatings containing microcrystalline diamond (MCD/Ti-C), nanocrystalline diamond (NCD), and boron-doped nanocrystalline diamond (B-NCD) with the NCD coatings being dense and homogeneous and the B-NCD coatings showing increased electrical conductivity. The ECAD process resulted in calcium phosphate coatings from stoichiometric and non-stoichiometric HAp. The deposition of HAp on the B-NCD films run at lower cathodic potentials and resulted both in the highest coating mass and the most homogenous appearance. Initial cell biological investigations showed an improved cell adhesion in the order B-NCD>HAp/B-NCD>uncoated substrate. Cell proliferation was improved for both investigated coatings whereas ALP

  4. The Effect of Annealing on the Structural and Optical Properties of Titanium Dioxide Films Deposited by Electron Beam Assisted PVD

    Directory of Open Access Journals (Sweden)

    Yaser M. Abdulraheem

    2013-01-01

    Full Text Available Titanium dioxide thin films were deposited on crystalline silicon substrates by electron beam physical vapor deposition. The deposition was performed under vacuum ranging from 10−5 to 10−6 Torr without process gases, resulting in homogeneous TiO2-x layers with a thickness of around 100 nm. Samples were then annealed at high temperatures ranging from 500°C to 800°C for 4 hours under nitrogen, and their structural and optical properties along with their chemical structure were characterized before and after annealing. The chemical and structural characterization revealed a substoichiometric TiO2-x film with oxygen vacancies, voids, and an interface oxide layer. It was found from X-ray diffraction that the deposited films were amorphous and crystallization to anatase phase occurred for annealed samples and was more pronounced for annealing temperatures above 700°C. The refractive index obtained through spectroscopic ellipsometry ranged between 2.09 and 2.37 in the wavelength range, 900 nm to 400 nm for the as-deposited sample, and jumped to the range between 2.23 and 2.65 for samples annealed at 800°C. The minimum surface reflectance changed from around 0.6% for the as-deposited samples to 2.5% for the samples annealed at 800°C.

  5. Properties of Ultrathin Al2O3-TiO2 Nanolaminate Films for Gate Dielectric Applications Deposited by Plasma-Assisted Atomic Layer Deposition

    Science.gov (United States)

    Garces, Nelson; Meyer, David; Nepal, Neeraj; Wheeler, Virginia; Eddy, Charles

    2012-02-01

    High permittivity dielectrics such as Al2O3, HfO2, Ta2O5, TiO2, etc., are an essential component of aggressively-scaled III-V and graphene field effect transistors (FETs) where insulators are necessary to reduce gate leakage current while maintaining high gate capacitance and charge control of the channel. Atomic layer deposition (ALD) has the capability to deposit hybrid films, or nanolaminates, of two or more dielectrics that have unique properties. Thin [Al2O3+TiO2] nanolaminates with varying TiO2 and Al2O3 content were deposited on n-Si substrates at ˜225-300 C using ALD. A nanolaminate is composed of bilayers, defined as the sum of (x)Al2O3 and (y)TiO2, where x, and y indicate the number of times a component monolayer is repeated. While the overall thickness of the dielectric was held at ˜ 17-20 nm, the relative ratio of Al2O3 to TiO2 in the bilayer stack was varied to evaluate changes in the material properties and electrical performance of the oxides. C-V and I-V measurements on various [(x)TiO2+(y)Al2O3] MOS capacitors were taken. The high-TiO2-content films show limited evidence of oxide charge trapping and relatively large dielectric constants (κ˜15), whereas the high-Al2O3-content films offer a larger optical bandgap and improved suppression of leakage current. We will discuss the properties of very thin nanolaminates and their possible use as gate oxides. Morphological, electrical, and XPS composition assessments will be presented.

  6. Wide band gap semiconductor templates

    Energy Technology Data Exchange (ETDEWEB)

    Arendt, Paul N. (Los Alamos, NM); Stan, Liliana (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); DePaula, Raymond F. (Santa Fe, NM); Usov, Igor O. (Los Alamos, NM)

    2010-12-14

    The present invention relates to a thin film structure based on an epitaxial (111)-oriented rare earth-Group IVB oxide on the cubic (001) MgO terminated surface and the ion-beam-assisted deposition ("IBAD") techniques that are amendable to be over coated by semiconductors with hexagonal crystal structures. The IBAD magnesium oxide ("MgO") technology, in conjunction with certain template materials, is used to fabricate the desired thin film array. Similarly, IBAD MgO with appropriate template layers can be used for semiconductors with cubic type crystal structures.

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

    International Nuclear Information System (INIS)

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

  8. Development and characterization of a layer by layer ultrasound assisted spray deposition process for thin polymer films

    Science.gov (United States)

    Balakrishnan, Anandh

    An Ultrasound assisted Atomization (UA) system has been developed and investigated to synthesize ˜20microm polyurethane thin films with uniform, repeatable thickness and microstructure. The UA system comprised a 20 kHz atomizer probe mounted on 750 W/cm2 transducer, a heated glass chamber and a rotating substrate. The rationale for the work has been built through a careful Design of Experiments (DoE) that sought to answer questions regarding the process-microstructure relationships from both the spray and material points of view. The independent variables chosen were the polymer solution weight percentage (0.2%, 2%, and 4%), power amplitude (energy) percentage supplied to the nozzle (23%, 29%, 37%, and 46%),the temperature of deposition (45°C, 80°C) and flow rate (50microL/min, 150microL/min). The research questions focused on influence of the process parameters on the microstructure and properties of the film. One of the problems involved fixing the trajectory of the spray and also making use of the droplet surfaces created by the spray. To achieve this, a simple air-draft attachment was devised and the influence of the same was evaluated through process and film characterization experiments. A mechanism for the draft has been schematically provided. The use of such a draft to fabricate thin polymer films via ultrasound atomization has not been achieved before and represents a 'first step' in advancing this ultrasound technology. The primary findings of the work were that the film microstructure and properties were heavily influenced by the flow rate, energy of atomization, and test temperature. In addition, the droplet diameters seemed to be readily amenable to change for the 0.2 and 2% solutions and the use of the air-draft made the process feasible, repeatable and accurate. For the 4% solutions, viscosity seemed to stabilize the liquid solution film at the tip requiring larger energies of atomization. In all, relative to the 0.2% films the fracture strengths

  9. Influence of the voltage waveform during nanocomposite layer deposition by aerosol-assisted atmospheric pressure Townsend discharge

    Science.gov (United States)

    Profili, J.; Levasseur, O.; Naudé, N.; Chaneac, C.; Stafford, L.; Gherardi, N.

    2016-08-01

    This work examines the growth dynamics of TiO2-SiO2 nanocomposite coatings in plane-to-plane Dielectric Barrier Discharges (DBDs) at atmospheric pressure operated in a Townsend regime using nebulized TiO2 colloidal suspension in hexamethyldisiloxane as the growth precursors. For low-frequency (LF) sinusoidal voltages applied to the DBD cell, with voltage amplitudes lower than the one required for discharge breakdown, Scanning Electron Microscopy of silicon substrates placed on the bottom DBD electrode reveals significant deposition of TiO2 nanoparticles (NPs) close to the discharge entrance. On the other hand, at higher frequencies (HF), the number of TiO2 NPs deposited strongly decreases due to their "trapping" in the oscillating voltage and their transport along the gas flow lines. Based on these findings, a combined LF-HF voltage waveform is proposed and used to achieve significant and spatially uniform deposition of TiO2 NPs across the whole substrate surface. For higher voltage amplitudes, in the presence of hexamethyldisiloxane and nitrous oxide for plasma-enhanced chemical vapor deposition of inorganic layers, it is found that TiO2 NPs become fully embedded into a silica-like matrix. Similar Raman spectra are obtained for as-prepared TiO2 NPs and for nanocomposite TiO2-SiO2 coating, suggesting that plasma exposure does not significantly alter the crystalline structure of the TiO2 NPs injected into the discharge.

  10. The effects of the forward speed and air volume of an air-assisted sprayer on spray deposition in tendone trained vineyards

    Directory of Open Access Journals (Sweden)

    Simone Pascuzzi

    2013-12-01

    Full Text Available This paper reports the results of spray application trials in a tendone trained vineyard in order to evaluate the influence of forward speed and air volume on the foliar deposition of plant protection products (PPPs, maintaining roughly constant the volume applied. The trials used an air-assisted sprayer with a centrifugal fan and 4+4 adjustable fan-shaped diffusers, each with a nozzle-holder group. A full factorial experimental design was implemented, with three forward speeds and two airflow rates, organised with a randomised complete block design including three replicates. In order to consider the influence of canopy development, the tests (one spray application for each replicate of a mixture containing a water-soluble food dye as a tracer were replicated during two phenological stages: i the end of flowering; and ii berry touch. Leaves were picked at random from the canopy after each spray treatment, and foliar PPP deposition was evaluated using a spectrophotometer. This analysis of foliar deposition showed that the airflow rates produced by the fan were unsuitable for the dense canopy typical of this type of vineyard. However, the special shape of the diffusers may make this sprayer effective if the main objective of pesticide applications in tendone trained table grape vineyards is to control bunch diseases.

  11. Carbon Nitride Thin Films Deposited by Plasma Assisted Nd∶YAG Laser Ablation of Graphite in N2+H2 Atmosphere

    Institute of Scientific and Technical Information of China (English)

    YU Wei; WANG Shufang; ZHANG Lianshui; LI Xiaowei; FU Guangsheng

    2001-01-01

    Carbon nitride thin films are deposited on silicon wafers by 532 nm Nd∶YAG laser ablation of graphite in the N2+H2 atmosphere assisted by a dc glow discharge plasma at a higher gas pressure of about 4.0 kPa. The properties of the thin films are investigated by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and X-ray diffraction (XRD). The results show that the deposited films are composed of α-C3N4, β-C3N4 phase and have the N/C atomic ratio of 2.01. The optical emission spectroscopy (OES) studies indicate that the introduction of a dc glow discharge and the adoption of a higher gas pressure during the film deposition are favorable to the net generation of the atomic N, CN radicals and N+2 in B2Σ+u excited state in the plasma, which are considered to play a major role in the synthesis of carbon nitride.

  12. Thin films of thermoelectric compound Mg{sub 2}Sn deposited by co-sputtering assisted by multi-dipolar microwave plasma

    Energy Technology Data Exchange (ETDEWEB)

    Le-Quoc, H., E-mail: huy.le-quoc@lpsc.in2p3.fr [Laboratoire de Physique Subatomique et de Cosmologie - CNRS/UJF/Grenoble INP, 53 rue des Martyrs, 38026 Grenoble, Cedex (France); Institut Neel, CNRS, BP 166, F-38042, Grenoble, Cedex 9 (France); Lacoste, A., E-mail: ana.lacoste@ujf-grenoble.fr [Laboratoire de Physique Subatomique et de Cosmologie - CNRS/UJF/Grenoble INP, 53 rue des Martyrs, 38026 Grenoble, Cedex (France); Hlil, E.K. [Institut Neel, CNRS, BP 166, F-38042, Grenoble, Cedex 9 (France); Bes, A.; Vinh, T. Tan [Laboratoire de Physique Subatomique et de Cosmologie - CNRS/UJF/Grenoble INP, 53 rue des Martyrs, 38026 Grenoble, Cedex (France); Fruchart, D. [Institut Neel, CNRS, BP 166, F-38042, Grenoble, Cedex 9 (France); Skryabina, N. [Department of Physics, Perm State University, 614990 Perm (Russian Federation)

    2011-10-13

    Highlights: > Mg{sub 2}Sn thin films deposited by plasma co-sputtering, on silicon and glass substrates. > Formation of nano-grained polycrystalline films on substrates at room temperature. > Structural properties vary with target biasing and target-substrate distance. > Formation of the hexagonal phase of Mg{sub 2}Sn in certain deposition conditions. > Power factor {approx}5.0 x 10{sup -3} W K{sup -2} m{sup -1} for stoichiometric Mg{sub 2}Sn films doped with {approx}1 at.% Ag. - Abstract: Magnesium stannide (Mg{sub 2}Sn) thin films doped with Ag intended for thermoelectric applications are deposited on both silicon and glass substrates at room temperature by plasma assisted co-sputtering. Characterization by scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction confirms the formation of fine-grained polycrystalline thin films with thickness of 1-3 {mu}m. Stoichiometry, microstructure and crystal structure of thin films are found to vary with target biasing and the distance from targets to substrate. Measurements of electrical resistivity and Seebeck coefficient at room temperature show the maximum power factor of {approx}5.0 x 10{sup -3} W K{sup -2} m{sup -1} for stoichiometric Mg{sub 2}Sn thin films doped with {approx}1 at.% Ag.

  13. Characterisation of Pristine and Recoated electron beam evaporation plasma-assisted physical vapour deposition Cr-N coatings on AISI M2 steel and WC-Co substrates

    International Nuclear Information System (INIS)

    This paper is focussed on the characterisation of electron beam evaporation plasma-assisted physical vapour deposition Cr-N coatings deposited on AISI M2 steel and hardmetal (K10) substrates in two different conditions: Pristine (i.e., coated) and Recoated (i.e., stripped and recoated). Analytical methods, including X-ray diffraction (XRD), scanning electron microscopy, scratch adhesion and pin-on-disc tests were used to evaluate several coating properties. XRD analyses indicated that both Pristine and Recoated coatings consisted of a mixture of hexagonal Cr2N and cubic CrN, regardless of substrate type. For the M2 steel substrate, only small differences were found in terms of coating phases, microstructure, adhesion, friction and wear coefficients between Pristine and Recoated. Recoated on WC-Co (K10) exhibited a less dense microstructure and significant inferior adhesion compared to Pristine on WC-Co (K10). The wear coefficient of Recoated on WC-Co was 100 times higher than those exhibited by all other specimens. The results obtained confirm that the stripping process did not adversely affect the Cr-N properties when this coating was deposited onto M2 steel substrates, but it is clear from the unsatisfactory tribological performance of Recoated on WC-Co that the stripping process is unsuitable for hardmetal substrates

  14. Growth of thick La2Zr2O7 buffer layers for coated conductors by polymer-assisted chemical solution deposition

    Science.gov (United States)

    Zhang, Xin; Zhao, Yong; Xia, Yudong; Guo, Chunsheng; Cheng, C. H.; Zhang, Yong; Zhang, Han

    2015-06-01

    La2Zr2O7 (LZO) epitaxial films have been deposited on LaAlO3 (LAO) (1 0 0) single-crystal surface and bi-axially textured NiW (2 0 0) alloy substrate by polymer-assisted chemical solution deposition, and afterwards studied with XRD, SEM and AFM approaches. Highly in-plane and out-of-plane oriented, dense, smooth, crack free and with a sufficient thickness (>240 nm) LZO buffer layers have been obtained on LAO (1 0 0) single-crystal surface; The films deposited on NiW (2 0 0) alloy substrate are also found with high degree in-plane and out-of-plane texturing, good density with pin-hole-free, micro-crack-free nature and a thickness of 300 nm. Highly epitaxial 500 nm thick YBa2Cu3O7-x (YBCO) thin film exhibits the self-field critical current density (Jc) reached 1.3 MA/cm2 at 77 K .These results demonstrate the LZO epi-films obtained with current techniques have potential to be a buffer layer for REBCO coated conductors.

  15. Sm-doped CeO{sub 2} single buffer layer for YBCO coated conductors by polymer assisted chemical solution deposition (PACSD) method

    Energy Technology Data Exchange (ETDEWEB)

    Li, G.; Pu, M.H.; Sun, R.P.; Wang, W.T.; Wu, W.; Zhang, X.; Yang, Y. [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu 610031 (China); Cheng, C.H. [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu 610031 (China); School of Materials Science and Engineering, University of New South Wales, Sydney, 2052 NSW (Australia); Zhao, Y. [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu 610031 (China); School of Materials Science and Engineering, University of New South Wales, Sydney, 2052 NSW (Australia)], E-mail: yzhao@home.swjtu.edu.cn

    2008-10-20

    An over 150 nm thick Sm{sub 0.2}Ce{sub 0.8}O{sub 1.9-x} (SCO) single buffer layer has been deposited on bi-axially textured NiW (2 0 0) alloy substrate. Highly in-plane and out-of-plane oriented, dense, smooth and crack free SCO single layer has been obtained via a polymer-assisted chemical solution deposition (PACSD) approach. YBCO thin film has been deposited equally via a PACSD route on the SCO-buffered NiW, the as grown YBCO yielding a sharp transition at T{sub c0} = 87 K as well as J{sub c}(0 T, 77 K) {approx} 1 MA/cm{sup 2}. These results indicates that RE (lanthanides other than Ce) doping may be an effective approach to improve the critical thickness of solution derived CeO{sub 2} film, which renders it a promising candidate as single buffer layer for YBCO coated conductors.

  16. Stepwise mechanism and H2O-assisted hydrolysis in atomic layer deposition of SiO2 without a catalyst.

    Science.gov (United States)

    Fang, Guo-Yong; Xu, Li-Na; Wang, Lai-Guo; Cao, Yan-Qiang; Wu, Di; Li, Ai-Dong

    2015-01-01

    Atomic layer deposition (ALD) is a powerful deposition technique for constructing uniform, conformal, and ultrathin films in microelectronics, photovoltaics, catalysis, energy storage, and conversion. The possible pathways for silicon dioxide (SiO2) ALD using silicon tetrachloride (SiCl4) and water (H2O) without a catalyst have been investigated by means of density functional theory calculations. The results show that the SiCl4 half-reaction is a rate-determining step of SiO2 ALD. It may proceed through a stepwise pathway, first forming a Si-O bond and then breaking Si-Cl/O-H bonds and forming a H-Cl bond. The H2O half-reaction may undergo hydrolysis and condensation processes, which are similar to conventional SiO2 chemical vapor deposition (CVD). In the H2O half-reaction, there are massive H2O molecules adsorbed on the surface, which can result in H2O-assisted hydrolysis of the Cl-terminated surface and accelerate the H2O half-reaction. These findings may be used to improve methods for the preparation of SiO2 ALD and H2O-based ALD of other oxides, such as Al2O3, TiO2, ZrO2, and HfO2.

  17. Growth of thick La{sub 2}Zr{sub 2}O{sub 7} buffer layers for coated conductors by polymer-assisted chemical solution deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xin, E-mail: xzhang@my.swjtu.edu.cn [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains, Ministry of Education of China, Superconductivity and New Energy Center (SNEC), Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Zhao, Yong, E-mail: yzhao@swjtu.edu.cn [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains, Ministry of Education of China, Superconductivity and New Energy Center (SNEC), Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); School of Materials Science and Engineering, University of New South Wales, Sydney, 2052 NSW (Australia); Xia, Yudong [State Key Lab of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Guo, Chunsheng [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains, Ministry of Education of China, Superconductivity and New Energy Center (SNEC), Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Cheng, C.H. [School of Materials Science and Engineering, University of New South Wales, Sydney, 2052 NSW (Australia); Zhang, Yong [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains, Ministry of Education of China, Superconductivity and New Energy Center (SNEC), Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Zhang, Han [Department of Physics, Peking University, Beijing 100871 (China)

    2015-06-15

    Highlights: • We develops a low-cost and high-efficient technology of fabricating LZO buffer layers. • Sufficient thickness LZO buffer layers have been obtained on NiW (2 0 0) alloy substrate. • Highly biaxially textured YBCO thin film has been deposited on LZO/NiW. - Abstract: La{sub 2}Zr{sub 2}O{sub 7} (LZO) epitaxial films have been deposited on LaAlO{sub 3} (LAO) (1 0 0) single-crystal surface and bi-axially textured NiW (2 0 0) alloy substrate by polymer-assisted chemical solution deposition, and afterwards studied with XRD, SEM and AFM approaches. Highly in-plane and out-of-plane oriented, dense, smooth, crack free and with a sufficient thickness (>240 nm) LZO buffer layers have been obtained on LAO (1 0 0) single-crystal surface; The films deposited on NiW (2 0 0) alloy substrate are also found with high degree in-plane and out-of-plane texturing, good density with pin-hole-free, micro-crack-free nature and a thickness of 300 nm. Highly epitaxial 500 nm thick YBa{sub 2}Cu{sub 3}O{sub 7−x} (YBCO) thin film exhibits the self-field critical current density (Jc) reached 1.3 MA/cm{sup 2} at 77 K .These results demonstrate the LZO epi-films obtained with current techniques have potential to be a buffer layer for REBCO coated conductors.

  18. Direct synthesis of large area graphene on insulating substrate by gallium vapor-assisted chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Katsuhisa, E-mail: k.murakami@bk.tsukuba.ac.jp; Hiyama, Takaki; Kuwajima, Tomoya; Fujita, Jun-ichi [Institute of Applied Physics, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8573 (Japan); Tsukuba Research Center for Interdisciplinary Materials Science, University of Tsukuba, Tsukuba 305-8573 (Japan); Tanaka, Shunsuke; Hirukawa, Ayaka [Institute of Applied Physics, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8573 (Japan); Kano, Emi [Institute of Applied Physics, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8573 (Japan); National Institute for Materials Science, Tsukuba 305-0047 (Japan); Takeguchi, Masaki [National Institute for Materials Science, Tsukuba 305-0047 (Japan)

    2015-03-02

    A single layer of graphene with dimensions of 20 mm × 20 mm was grown directly on an insulating substrate by chemical vapor deposition using Ga vapor catalysts. The graphene layer showed highly homogeneous crystal quality over a large area on the insulating substrate. The crystal quality of the graphene was measured by Raman spectroscopy and was found to improve with increasing Ga vapor density on the reaction area. High-resolution transmission electron microscopy observations showed that the synthesized graphene had a perfect atomic-scale crystal structure within its grains, which ranged in size from 50 nm to 200 nm.

  19. Substrate temperature influence on the properties of GaN thin films grown by hollow-cathode plasma-assisted atomic layer deposition

    International Nuclear Information System (INIS)

    Gallium nitride films were grown by hollow cathode plasma-assisted atomic layer deposition using triethylgallium and N2/H2 plasma. An optimized recipe for GaN film was developed, and the effect of substrate temperature was studied in both self-limiting growth window and thermal decomposition-limited growth region. With increased substrate temperature, film crystallinity improved, and the optical band edge decreased from 3.60 to 3.52 eV. The refractive index and reflectivity in Reststrahlen band increased with the substrate temperature. Compressive strain is observed for both samples, and the surface roughness is observed to increase with the substrate temperature. Despite these temperature dependent material properties, the chemical composition, E1(TO), phonon position, and crystalline phases present in the GaN film were relatively independent from growth temperature

  20. Substrate temperature influence on the properties of GaN thin films grown by hollow-cathode plasma-assisted atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Alevli, Mustafa, E-mail: mustafaalevli@marmara.edu.tr; Gungor, Neşe [Department of Physics, Faculty of Arts and Sciences, Marmara University, Goztepe, 34722 Istanbul (Turkey); Haider, Ali; Kizir, Seda; Leghari, Shahid A.; Biyikli, Necmi, E-mail: biyikli@unam.bilkent.edu.tr [Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent, 06800 Ankara, Turkey and National Nanotechnology Research Center (UNAM), Bilkent University, Bilkent, 06800 Ankara (Turkey)

    2016-01-15

    Gallium nitride films were grown by hollow cathode plasma-assisted atomic layer deposition using triethylgallium and N{sub 2}/H{sub 2} plasma. An optimized recipe for GaN film was developed, and the effect of substrate temperature was studied in both self-limiting growth window and thermal decomposition-limited growth region. With increased substrate temperature, film crystallinity improved, and the optical band edge decreased from 3.60 to 3.52 eV. The refractive index and reflectivity in Reststrahlen band increased with the substrate temperature. Compressive strain is observed for both samples, and the surface roughness is observed to increase with the substrate temperature. Despite these temperature dependent material properties, the chemical composition, E{sub 1}(TO), phonon position, and crystalline phases present in the GaN film were relatively independent from growth temperature.

  1. Vertical La0.7Ca0.3MnO3 nanorods tailored by high magnetic field assisted pulsed laser deposition

    Science.gov (United States)

    Zhang, Kejun; Dai, Jianming; Zhu, Xuebin; Zhu, Xiaoguang; Zuo, Xuzhong; Zhang, Peng; Hu, Ling; Lu, Wenjian; Song, Wenhai; Sheng, Zhigao; Wu, Wenbin; Sun, Yuping; Du, Youwei

    2016-01-01

    La0.7Ca0.3MnO3 (LCMO) thin films on (LaAlO3)0.3(Sr2AlTaO6)0.7 (001) [LSAT (001)] single crystal substrates have been prepared by high magnetic field assisted pulsed laser deposition (HMF-PLD) developed by ourselves. Uniformly sized and vertically aligned nanorod structures can be obtained under an applied high magnetic field above 5 T, and the dimension size of the nanorods can be manipulated by varying the applied magnetic field. It is found that the magnetic anisotropy is strongly correlated to the dimension size of the nanorods. A significantly enhanced low-field magnetoresistance (LFMR) of -36% under 0.5 T at 100 K can be obtained due to the enhanced carrier scattering at the vertical grain boundaries between the nanorods for the LCMO films. The growth mechanism of the nanorods has been also discussed, which can be attributed to the variation of deposition rate, adatom surface diffusion, and nucleation induced by the application of a high magnetic field in the film processing. The successful achievements of such vertical nanorod structures will provide an instructive route to investigate the physical nature of these nanostructures and achieve nanodevice manipulation.

  2. Effect of doping on the Structural and Optical Properties of SnO2 Thin Films fabricated by Aerosol Assisted Chemical Vapor Deposition

    International Nuclear Information System (INIS)

    In order to achieve high conductivity and transmittance of transparent conducting oxide (TCO), we attempted to fabricate Mg doped SnO2 (MgxSn1−xO2) thin films and characterized them for their structural and optical properties. The MgxSn1−xO2 thin films have been deposited on glass substrate by using aero-sole assisted chemical vapor deposition (AACVD). The molar concentration of Mg concentration was changed from 0 to 8%. The confirmation of tetragonal structure and particle size (32 to 87nm) has been calculated of thin films by XRD. The surface roughness is decreased with the increase of the dopant concentration, which has been investigated by atomic force microscopy (AFM). The optical transmission has increased from 54 to 78% and the band gape of pure SnO2 has been found to be in the range of 3.76eV and it is shifted to 3.69eV for 6Wt % Mg doping and then increase on further increasing the Mg doping.

  3. ECR plasma-assisted PVD deposition of α-Fe thin film on melt-spun Nd-Fe-B alloys

    Science.gov (United States)

    Fedorchenko, V. D.; Bovda, A. M.; Bovda, V. A.; Chen, C. H.; Chebotarev, V. V.; Garkusha, I. E.; Liu, S.; Medvedev, A. V.; Tereshin, V. I.

    2008-03-01

    The paper deals with plasma-assisted PVD of α-Fe thin film onto the melt-spun Nd-Fe-B-Co ribbons. The parameters of the plasma created by a planar rectangular ECR plasma source with a multipolar magnetic field and a double-slot antenna were as follows: electron density up to 1×1010 cm-3, electron temperature ˜22 eV, the current density of ion flow to grounded disk-substrate was equal to ˜0.5 mA/cm2 at the gas flow of 1 sccm, the microwave power was up to 300W. After degreasing and ultrasonic washing of Nd-Fe-B-Co ribbons, follow by ion etching, the deposition process was realized at a pulsed voltage bias of -1000 V with frequency 100 Hz, total current on the target 240 mA, current density 2.9 mA/cm2. The deposition rate of 0.0083 μm/min was achieved. The process continued for 2 hour. It was found that the magnetic melt-spun ribbons were homogeneously coated with the α-Fe film having a typical thickness of 1 μm.

  4. Electrical conduction and dielectric relaxation properties of AlN thin films grown by hollow-cathode plasma-assisted atomic layer deposition

    Science.gov (United States)

    Altuntas, Halit; Bayrak, Turkan; Kizir, Seda; Haider, Ali; Biyikli, Necmi

    2016-07-01

    In this study, aluminum nitride (AlN) thin films were deposited at 200 °C, on p-type silicon substrates utilizing a capacitively coupled hollow-cathode plasma source integrated atomic layer deposition (ALD) reactor. The structural properties of AlN were characterized by grazing incidence x-ray diffraction, by which we confirmed the hexagonal wurtzite single-phase crystalline structure. The films exhibited an optical band edge around ˜5.7 eV. The refractive index and extinction coefficient of the AlN films were measured via a spectroscopic ellipsometer. In addition, to investigate the electrical conduction mechanisms and dielectric properties, Al/AlN/p-Si metal-insulator-semiconductor capacitor structures were fabricated, and current density-voltage and frequency dependent (7 kHz-5 MHz) dielectric constant measurements (within the strong accumulation region) were performed. A peak of dielectric loss was observed at a frequency of 3 MHz and the Cole-Davidson empirical formula was used to determine the relaxation time. It was concluded that the native point defects such as nitrogen vacancies and DX centers formed with the involvement of Si atoms into the AlN layers might have influenced the electrical conduction and dielectric relaxation properties of the plasma-assisted ALD grown AlN films.

  5. Influence of WC-Co substrate pretreatment on diamond film deposition by laser-assisted combustion synthesis.

    Science.gov (United States)

    Veillère, Amélie; Guillemet, Thomas; Xie, Zhi Qiang; Zuhlke, Craig A; Alexander, Dennis R; Silvain, Jean-François; Heintz, Jean-Marc; Chandra, Namas; Lu, Yong Feng

    2011-04-01

    The quality of diamond films deposited on cemented tungsten carbide substrates (WC-Co) is limited by the presence of the cobalt binder. The cobalt in the WC-Co substrates enhances the formation of nondiamond carbon on the substrate surface, resulting in a poor film adhesion and a low diamond quality. In this study, we investigated pretreatments of WC-Co substrates in three different approaches, namely, chemical etching, laser etching, and laser etching followed by acid treatment. The laser produces a periodic surface pattern, thus increasing the roughness and releasing the stress at the interfaces between the substrate and the grown diamond film. Effects of these pretreatments have been analyzed in terms of microstructure and cobalt content. Raman spectroscopy was conducted to characterize both the diamond quality and compressive residual stress in the films. PMID:21462974

  6. Core and grain boundary sensitivity of tungsten-oxide sensor devices by molecular beam assisted particle deposition

    Science.gov (United States)

    Huelser, T. P.; Lorke, A.; Ifeacho, P.; Wiggers, H.; Schulz, C.

    2007-12-01

    In this study, we investigate the synthesis of WO3 and WOx (2.6≥x≤2.8) by adding different concentrations of tungsten hexafluoride (WF6) into a H2/O2/Ar premixed flame within a low-pressure reactor equipped with a particle-mass spectrometer (PMS). The PMS results show that mean particle diameters dp between 5 and 9 nm of the as-synthesized metal-oxides can be obtained by varying the residence time and precursor concentration in the reactor. This result is further validated by N2 adsorption measurements on the particle surface, which yielded a 91 m2/g surface area, corresponding to a spherical particle diameter of 9 nm (Brunauer-Emmett-Teller technique). H2/O2 ratios of 1.6 and 0.63 are selected to influence the stoichiometry of the powders, resulting in blue-colored WOx and white WO3 respectively. X-ray diffraction (XRD) analysis of the as-synthesized materials indicates that the powders are mostly amorphous, and the observed broad reflexes can be attributed to the orthorhombic structure of β-WO3. Thermal annealing at 973 K for 3 h in air resulted in crystalline WO3 comprised of both monoclinic and orthorhombic phases. The transmission electron microscope micrograph analysis shows that the particles exhibit spherical morphology with some degree of agglomeration. Impedance spectroscopy is used for the electrical characterization of tungsten-oxide thin films with a thickness of 50 nm. Furthermore, the temperature-dependent gas-sensing properties of the material deposited on interdigital capacitors are investigated. Sensitivity experiments reveal two contributions to the overall sensitivity, which result from the surface and the core of each particle.

  7. Selective synthesis of large diameter, highly conductive and high density single-walled carbon nanotubes by a thiophene-assisted chemical vapor deposition method on transparent substrates

    Science.gov (United States)

    Li, Jinghua; Otsuka, Keigo; Zhang, Xiao; Maruyama, Shigeo; Liu, Jie

    2016-07-01

    Selective synthesis of single-walled carbon nanotubes (SWNTs) with controlled properties is an important research topic for SWNT studies. Here we report a thiophene-assisted chemical vapor deposition (CVD) method to directly grow highly conductive SWNT thin films on substrates, including transparent ones. By adding low concentration thiophene into the carbon feedstock (ethanol), the as-prepared carbon nanotubes demonstrate an obvious up-shift in the diameter distribution while the single-walled structure is still retained. In the proposed mechanism, the change in the diameter is sourced from the increase in the carbon yield induced by the sulfur-containing compound. Such SWNTs are found to possess high conductivity with 95% SWNTs demonstrating on/off ratios lower than 100 in transistors. More importantly, it is further demonstrated that this method can be used to directly synthesize dense SWNT networks on transparent substrates which can be utilized as transparent conductive films (TCFs) with very high transparency. Such TCFs can be applied to fabricate a light modulating window as a proof-of-concept. The present work provides important insights into the growth mechanism of SWNTs and great potential for the preparation of TCFs with high scalability, easy operation and low cost.Selective synthesis of single-walled carbon nanotubes (SWNTs) with controlled properties is an important research topic for SWNT studies. Here we report a thiophene-assisted chemical vapor deposition (CVD) method to directly grow highly conductive SWNT thin films on substrates, including transparent ones. By adding low concentration thiophene into the carbon feedstock (ethanol), the as-prepared carbon nanotubes demonstrate an obvious up-shift in the diameter distribution while the single-walled structure is still retained. In the proposed mechanism, the change in the diameter is sourced from the increase in the carbon yield induced by the sulfur-containing compound. Such SWNTs are found to

  8. Resonant and nonresonant vibrational excitation of ammonia molecules in the growth of gallium nitride using laser-assisted metal organic chemical vapour deposition

    Science.gov (United States)

    Golgir, Hossein Rabiee; Zhou, Yun Shen; Li, Dawei; Keramatnejad, Kamran; Xiong, Wei; Wang, Mengmeng; Jiang, Li Jia; Huang, Xi; Jiang, Lan; Silvain, Jean Francois; Lu, Yong Feng

    2016-09-01

    The influence of exciting ammonia (NH3) molecular vibration in the growth of gallium nitride (GaN) was investigated by using an infrared laser-assisted metal organic chemical vapor deposition method. A wavelength tunable CO2 laser was used to selectively excite the individual vibrational modes. Resonantly exciting the NH-wagging mode (v2) of NH3 molecules at 9.219 μm led to a GaN growth rate of 84 μm/h, which is much higher than the reported results. The difference between the resonantly excited and conventional thermally populated vibrational states was studied via resonant and nonresonant vibrational excitations of NH3 molecules. Resonant excitation of various vibrational modes was achieved at 9.219, 10.35, and 10.719 μm, respectively. Nonresonant excitation was conducted at 9.201 and 10.591 μm, similar to conventional thermal heating. Compared to nonresonant excitation, resonant excitation noticeably promotes the GaN growth rate and crystalline quality. The full width at half maximum value of the XRD rocking curves of the GaN (0002) and GaN (10-12) diffraction peaks decreased at resonant depositions and reached its minimum value of 45 and 53 arcmin, respectively, at the laser wavelength of 9.219 μm. According to the optical emission spectroscopic studies, resonantly exciting the NH3 v2 mode leads to NH3 decomposition at room temperature, reduces the formation of the TMGa:NH3 adduct, promotes the supply of active species in GaN formation, and, therefore, results in the increased GaN growth rate.

  9. Physisorbed-precursor-assisted atomic layer deposition of reliable ultrathin dielectric films on inert graphene surfaces for low-power electronics

    Science.gov (United States)

    Jeong, Seong-Jun; Kim, Hyo Won; Heo, Jinseong; Lee, Min-Hyun; Song, Hyun Jae; Ku, JiYeon; Lee, Yunseong; Cho, Yeonchoo; Jeon, Woojin; Suh, Hwansoo; Hwang, Sungwoo; Park, Seongjun

    2016-09-01

    Among the most fundamental challenges encountered in the successful incorporation of graphene in silicon-based electronics is the conformal growth of ultrathin dielectric films, especially those with thicknesses lower than 5 nm, on chemically inert graphene surfaces. Here, we present physisorbed-precursor-assisted atomic layer deposition (pALD) as an extremely robust method for fabricating such films. Using atomic-scale characterisation, it is confirmed that conformal and intact ultrathin Al2O3 films can be synthesised on graphene by pALD. The mechanism underlying the pALD process is identified through first-principles calculations based on density functional theory. Further, this novel deposition technique is used to fabricate two types of wafer-scale devices. It is found that the incorporation of a 5 nm-thick pALD Al2O3 gate dielectric film improves the performance of metal-oxide-graphene field-effect transistors to a greater extent than does the incorporation of a conventional ALD Al2O3 film. We also employ a 5 nm-thick pALD HfO2 film as a highly scalable dielectric layer with a capacitance equivalent oxide thickness of 1 nm in graphene-based tunnelling field-effect transistors fabricated on a glass wafer and achieve a subthreshold swing of 30 mV/dec. This significant improvement in switching allows for the low-voltage operation of an inverter within 0.5 V of both the drain and the gate voltages, thus paving the way for low-power electronics.

  10. Aligned synthesis of multi-walled carbon nanotubes with high purity by aerosol assisted chemical vapor deposition: Effect of water vapor

    International Nuclear Information System (INIS)

    Aligned multi-walled carbon nanotubes (MWCNTs) with high purity and bulk yield were achieved on a silicon substrate by an aerosol-assisted chemical vapor deposition. The introduction of specific amounts of water vapor played a key role in in situ controlling the purity and surface defects of the nanotubes. The morphology, surface quality and structure of MWCNTs were characterized by secondary and backscattered electron imaging in a field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). Crystallinity and defects of the MWCNTs' were investigated by high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy. In this work, water vapor was found to provide a weak oxidative environment, which enhanced and purified the MWCNTs' growth. However, excessive water vapor would inhibit the MWCNTs growth with a poor surface quality. In addition, it has been found that the surface morphology of the CNTs can be modified intentionally through producing some surface defects by tuning the amount of the water vapor, which may offer more nucleation sites on the chemically inert CNT surface for various applications such as catalyst support.

  11. Films of brookite TiO{sub 2} nanorods/nanoparticles deposited by matrix-assisted pulsed laser evaporation as NO{sub 2} gas-sensing layers

    Energy Technology Data Exchange (ETDEWEB)

    Caricato, A.P.; Cesaria, M.; Luches, A.; Martino, M. [University of Salento, Department of Physics, Lecce (Italy); Buonsanti, R. [Istituto di Nanoscienze del CNR, National Nanotechnology Laboratory (NNL), Lecce (Italy); Catalano, M.; Manera, M.G.; Taurino, A.; Rella, R. [IMM-CNR, Institute for Microelectronics and Microsystems, Lecce (Italy); Cozzoli, P.D. [Istituto di Nanoscienze del CNR, National Nanotechnology Laboratory (NNL), Lecce (Italy); University of Salento, Department of Innovation Engineering, Lecce (Italy)

    2011-09-15

    Titanium dioxide (TiO{sub 2}) nanorods in the brookite phase, with average dimensions of 3-4 nm x 20-50 nm, were synthesized by a wet-chemical aminolysis route and used as precursors for thin films that were deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. A nanorod solution in toluene (0.016 wt% TiO{sub 2}) was frozen at the liquid-nitrogen temperature and irradiated with a KrF excimer laser at a fluence of 350 mJ/cm{sup 2} and repetition rate of 10 Hz. Single-crystal Si wafers, silica slides, carbon-coated Cu grids and alumina interdigitated slabs were used as substrates to allow performing different characterizations. Films fabricated with 6000 laser pulses had an average thickness of {proportional_to}150 nm, and a complete coverage of the selected substrate as achieved. High-resolution scanning and transmission electron microscopy investigations evidenced the formation of quite rough films incorporating individually distinguishable TiO{sub 2} nanorods and crystalline spherical nanoparticles with an average diameter of {proportional_to}13 nm. Spectrophotometric analysis showed high transparency through the UV-Vis spectral range. Promising resistive sensing responses to 1 ppm of NO{sub 2} mixed in dry air were obtained. (orig.)

  12. Films of brookite TiO2 nanorods/nanoparticles deposited by matrix-assisted pulsed laser evaporation as NO2 gas-sensing layers

    Science.gov (United States)

    Caricato, A. P.; Buonsanti, R.; Catalano, M.; Cesaria, M.; Cozzoli, P. D.; Luches, A.; Manera, M. G.; Martino, M.; Taurino, A.; Rella, R.

    2011-09-01

    Titanium dioxide (TiO2) nanorods in the brookite phase, with average dimensions of 3-4 nm × 20-50 nm, were synthesized by a wet-chemical aminolysis route and used as precursors for thin films that were deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. A nanorod solution in toluene (0.016 wt% TiO2) was frozen at the liquid-nitrogen temperature and irradiated with a KrF excimer laser at a fluence of 350 mJ/cm2 and repetition rate of 10 Hz. Single-crystal Si wafers, silica slides, carbon-coated Cu grids and alumina interdigitated slabs were used as substrates to allow performing different characterizations. Films fabricated with 6000 laser pulses had an average thickness of ˜150 nm, and a complete coverage of the selected substrate as achieved. High-resolution scanning and transmission electron microscopy investigations evidenced the formation of quite rough films incorporating individually distinguishable TiO2 nanorods and crystalline spherical nanoparticles with an average diameter of ˜13 nm. Spectrophotometric analysis showed high transparency through the UV-Vis spectral range. Promising resistive sensing responses to 1 ppm of NO2 mixed in dry air were obtained.

  13. Microstructural and optical properties of transparent conductive ZnO : Al : Mo films deposited by template-assisted sol–gel method

    Indian Academy of Sciences (India)

    H-Y He; J-F Huang; Z He; J Lu; Q Shen

    2014-05-01

    Transparent conductive ZnO : Al : Mo films with a molar ratio of Zn : Al : Mo = 99 : 0.99 : 0.01 were deposited on quartz glass substrate by a template-assisted sol-gel process and characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and UV–Vis and luminescent spectrophotometries. The four types of organic template have induced nanowire morphology with varying aspect ratio. Dip coating in one constant positive and reverse direction causes the parallel array of ZnO : Al : Mo nanowires on the quartz glass substrate. Long and parallel arrayed nanowire films show obviously blue shifts and enhanced transmittances in the UV-Vis light range. The PEG-1000 and PEG-2000 have optimal effects among four templates as constant weight content is used. The films show strong ultraviolet, violet and bluish violet emissions. The templates also lead to overall thicker film and more native defect and thereby remarkably enhancing photoluminescence of the films. Long chain organic template can be used to optimize the optical properties of the doped ZnO film.

  14. Nonlinear optical studies on 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid thin films deposited by matrix-assisted pulsed laser evaporation (MAPLE)

    Science.gov (United States)

    Matei, Andreea; Marinescu, Maria; Constantinescu, Catalin; Ion, Valentin; Mitu, Bogdana; Ionita, Iulian; Dinescu, Maria; Emandi, Ana

    2016-06-01

    We present results on a new, laboratory synthesized ferrocene-derivative, i.e. 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid. Thin films with controlled thickness are deposited by matrix-assisted pulsed laser evaporation (MAPLE), on quartz and silicon substrates, with the aim of evaluating the nonlinear optical properties for potential optoelectronic applications. Dimethyl sulfoxide was used as matrix, with 1% wt. concentration of the guest compound. The frozen target is irradiated by using a Nd:YAG laser (4ω/266 nm, 7 ns pulse duration, 10 Hz repetition rate), at low fluences ranging from 0.1 to 1 J/cm2. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) are used to probe the surface morphology of the films. Fourier transform infrared (FTIR) and Raman spectroscopy reveal similar structure of the thin film material when compared to the starting material. The optical properties of the thin films are investigated by spectroscopic-ellipsometry (SE), and the refractive index dependence with respect to temperature is studied. The second harmonic generation (SHG) potential is assessed by using a femtosecond Ti:sapphire laser (800 nm, 60-100 fs pulse duration, 80 MHz repetition rate), at 200 mW maximum output power, revealing that the SHG signal intensity is strongly influenced by the films' thickness.

  15. On-Tissue Derivatization via Electrospray Deposition for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Endogenous Fatty Acids in Rat Brain Tissues.

    Science.gov (United States)

    Wu, Qian; Comi, Troy J; Li, Bin; Rubakhin, Stanislav S; Sweedler, Jonathan V

    2016-06-01

    Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is used for the multiplex detection and characterization of diverse analytes over a wide mass range directly from tissues. However, analyte coverage with MALDI MSI is typically limited to the more abundant compounds, which have m/z values that are distinct from MALDI matrix-related ions. On-tissue analyte derivatization addresses these issues by selectively tagging functional groups specific to a class of analytes, while simultaneously changing their molecular masses and improving their desorption and ionization efficiency. We evaluated electrospray deposition of liquid-phase derivatization agents as a means of on-tissue analyte derivatization using 2-picolylamine; we were able to detect a range of endogenous fatty acids with MALDI MSI. When compared with airbrush application, electrospray led to a 3-fold improvement in detection limits and decreased analyte delocalization. Six fatty acids were detected and visualized from rat cerebrum tissue using a MALDI MSI instrument operating in positive mode. MALDI MSI of the hippocampal area allowed targeted fatty acid analysis of the dentate gyrus granule cell layer and the CA1 pyramidal layer with a 20-μm pixel width, without degrading the localization of other lipids during liquid-phase analyte derivatization.

  16. Effects of SiO_2 and TiO_2 on resistance stabilities of flexible indium-tin-oxide films prepared by ion assisted deposition

    Institute of Scientific and Technical Information of China (English)

    LI Yuqiong; YU Zhinong; WANG Wuyu; FAN Yuejiang; DING Zhao; XUE Wei

    2009-01-01

    Inorganic buffer layers such as SiO_2 or TiO_2 and transparent conductive indium-tin-oxide (ITO) films were prepared on polyethylene terephthalate (PET) substrates by ion assisted deposition (LAD) at room temperature, and the effects of SiO_2 and TiO_2 on the bending resis-tance performance of flexible ITO films were investigated. The results show that ITO films with SiO_2 or TiO_2 buffer layer have better resis-tance stabihties compared to ones without the buffer layer when the ITO films are inwards bent at a bending radius more than 1.2 cm and when the ITO films are outwards bent at a bending radius from 0.8 cm to 1.2 cm. ITO films with SiO_2 buffer layer have better resistance sta-bilities compared to ones with TiO_2 buffer layer after the ITO Films are bent several hundreds of cycles at the same bending radius, for the adhesion of SiO_2 is stronger than that of TiO_2. The compressive stress resulted from inward bending leads to the formation of more defects in the ITO films compared with the tensile stress arising from outward bending. SiO_2 and TiO_2 buffer layers can effectively improve the crystal-linity of ITO films in (400), (440) directions.

  17. Transport properties and microstructure of La0.7Sr0.3MnO3 nanocrystalline thin films grown by polymer-assisted chemical solution deposition

    Institute of Scientific and Technical Information of China (English)

    Min Zhang; Li Lv; Zhantao Wei; Xinsheng Yang; Xin Zhang

    2014-01-01

    Perovskite-based materials can be widely used in the aerospace and transportation field. Perovskite man-ganese oxides La0.7Sr0.3MnO3 (LSMO) thin films were grown on LaAlO3 (100) and Si (100) single crystal sub-strates by the polymer-assisted chemical solution deposi-tion (PACSD) method. Electronic transport behavior, microstructure, and magnetoresistance (MR) of LSMO thin films on different substrates were investigated. The resis-tance of LSMO films fabricated on LaAlO3 substrates is smaller than that on the Si substrates. The magnetic field reduces resistance of LSMO films both on Si and LAO in the wide temperature region, when the insulator-metal transition temperature shifts to higher temperature. The low-field magnetoresistance of LSMO films on Si in low temperature range at 1 T is larger than that of LSMO films on LAO. However, the MR of LSMO film on LAO films at room-temperature is about 5.17%. The thin films are smooth and dense with uniform nanocrystal size grain. These results demonstrate that PACSD is an effective technique for producing high quality LSMO films, which is significant to improve the magnetic properties and the application of automotive sensor.

  18. On-Tissue Derivatization via Electrospray Deposition for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Endogenous Fatty Acids in Rat Brain Tissues.

    Science.gov (United States)

    Wu, Qian; Comi, Troy J; Li, Bin; Rubakhin, Stanislav S; Sweedler, Jonathan V

    2016-06-01

    Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is used for the multiplex detection and characterization of diverse analytes over a wide mass range directly from tissues. However, analyte coverage with MALDI MSI is typically limited to the more abundant compounds, which have m/z values that are distinct from MALDI matrix-related ions. On-tissue analyte derivatization addresses these issues by selectively tagging functional groups specific to a class of analytes, while simultaneously changing their molecular masses and improving their desorption and ionization efficiency. We evaluated electrospray deposition of liquid-phase derivatization agents as a means of on-tissue analyte derivatization using 2-picolylamine; we were able to detect a range of endogenous fatty acids with MALDI MSI. When compared with airbrush application, electrospray led to a 3-fold improvement in detection limits and decreased analyte delocalization. Six fatty acids were detected and visualized from rat cerebrum tissue using a MALDI MSI instrument operating in positive mode. MALDI MSI of the hippocampal area allowed targeted fatty acid analysis of the dentate gyrus granule cell layer and the CA1 pyramidal layer with a 20-μm pixel width, without degrading the localization of other lipids during liquid-phase analyte derivatization. PMID:27181709

  19. Preparation of highly photocatalytic active CdS/TiO{sub 2} nanocomposites by combining chemical bath deposition and microwave-assisted hydrothermal synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Li, E-mail: qqhrll@163.com [College of Materials Science and Engineering, Qiqihar University, Qiqihar 161006 (China); Key Laboratory of Composite Modified Material of Colleges in Heilongjiang Province, Qiqihar 161006 (China); Wang, Lili [College of Materials Science and Engineering, Qiqihar University, Qiqihar 161006 (China); Hu, Tianyu [College of Environment and Resources, Jilin University, Changchun 130024 (China); Zhang, Wenzhi; Zhang, Xiuli; Chen, Xi [College of Materials Science and Engineering, Qiqihar University, Qiqihar 161006 (China)

    2014-10-15

    CdS/TiO{sub 2} nanocomposites were prepared from Cd and Ti (1:1 M ratio) using cetyltrimethylammonium bromide by a two-step chemical bath deposition (CBD) and microwave-assisted hydrothermal synthesis (MAHS) method. A series of nanocomposites with different morphologies and activities were prepared by varying the reaction time in the MAHS (2, 4, and 6 h). The crystal structure, morphology, and surface physicochemical properties of the nanocomposites were characterized by X-ray diffraction, UV–visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and N{sub 2} adsorption–desorption measurements. The results show that the CdS/TiO{sub 2} nanocomposites were composed of anatase TiO{sub 2} and hexagonal CdS phases with strong absorption in the visible region. The surface morphologies changed slightly with increasing microwave irradiation time, while the Brunauer–Emmett–Teller surface area increased remarkably. The photocatalytic degradation of methyl orange (MO) was investigated under UV light and simulated sunlight irradiation. The photocatalytic activity of the CdS/TiO{sub 2} (6 h) composites prepared by the MAHS method was higher than those of CdS, P25, and other CdS/TiO{sub 2} nanocomposites. The CdS/TiO{sub 2} (6 h) nanocomposites significantly affected the UV and microwave-assisted photocatalytic degradation of different dyes. To elucidate the photocatalytic reaction mechanism for the CdS/TiO{sub 2} nanocomposites, controlled experiments were performed by adding different radical scavengers. - Graphical abstract: CdS/TiO{sub 2} nanocomposites were prepared using CTAB by CBD combined with MAHS method. In addition, with increasing microwave irradiation time, the morphology of CdS/TiO{sub 2} changed from popcorn-like to wedge-like structure. - Highlights: • The CdS/TiO{sub 2} was prepared by CBD combined with MAHS two-step method under CTAB. • The morphologies of as-samples were different with the time of

  20. Preparation of highly photocatalytic active CdS/TiO2 nanocomposites by combining chemical bath deposition and microwave-assisted hydrothermal synthesis

    International Nuclear Information System (INIS)

    CdS/TiO2 nanocomposites were prepared from Cd and Ti (1:1 M ratio) using cetyltrimethylammonium bromide by a two-step chemical bath deposition (CBD) and microwave-assisted hydrothermal synthesis (MAHS) method. A series of nanocomposites with different morphologies and activities were prepared by varying the reaction time in the MAHS (2, 4, and 6 h). The crystal structure, morphology, and surface physicochemical properties of the nanocomposites were characterized by X-ray diffraction, UV–visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and N2 adsorption–desorption measurements. The results show that the CdS/TiO2 nanocomposites were composed of anatase TiO2 and hexagonal CdS phases with strong absorption in the visible region. The surface morphologies changed slightly with increasing microwave irradiation time, while the Brunauer–Emmett–Teller surface area increased remarkably. The photocatalytic degradation of methyl orange (MO) was investigated under UV light and simulated sunlight irradiation. The photocatalytic activity of the CdS/TiO2 (6 h) composites prepared by the MAHS method was higher than those of CdS, P25, and other CdS/TiO2 nanocomposites. The CdS/TiO2 (6 h) nanocomposites significantly affected the UV and microwave-assisted photocatalytic degradation of different dyes. To elucidate the photocatalytic reaction mechanism for the CdS/TiO2 nanocomposites, controlled experiments were performed by adding different radical scavengers. - Graphical abstract: CdS/TiO2 nanocomposites were prepared using CTAB by CBD combined with MAHS method. In addition, with increasing microwave irradiation time, the morphology of CdS/TiO2 changed from popcorn-like to wedge-like structure. - Highlights: • The CdS/TiO2 was prepared by CBD combined with MAHS two-step method under CTAB. • The morphologies of as-samples were different with the time of microwave increased. • Compared with TiO2, as-samples show

  1. Single and multi-layered core-shell structures based on ZnO nanorods obtained by aerosol assisted chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Sáenz-Trevizo, A.; Amézaga-Madrid, P.; Pizá-Ruiz, P.; Antúnez-Flores, W.; Ornelas-Gutiérrez, C.; Miki-Yoshida, M., E-mail: mario.miki@cimav.edu.mx

    2015-07-15

    Core–shell nanorod structures were prepared by a sequential synthesis using an aerosol assisted chemical vapor deposition technique. Several samples consisting of ZnO nanorods were initially grown over TiO{sub 2} film-coated borosilicate glass substrates, following the synthesis conditions reported elsewhere. Later on, a uniform layer consisting of individual Al, Ni, Ti or Fe oxides was grown onto ZnO nanorod samples forming the so-called single MO{sub x}/ZnO nanorod core–shell structures, where MO{sub x} was the metal oxide shell. Additionally, a three-layer core–shell sample was developed by growing Fe, Ti and Fe oxides alternately, onto the ZnO nanorods. The microstructure of the core–shell materials was characterized by grazing incidence X-ray diffraction, scanning and transmission electron microscopy. Energy dispersive X-ray spectroscopy was employed to corroborate the formation of different metal oxides. X-ray diffraction outcomes for single core–shell structures showed solely the presence of ZnO as wurtzite and TiO{sub 2} as anatase. For the multi-layered shell sample, the existence of Fe{sub 2}O{sub 3} as hematite was also detected. Morphological observations suggested the existence of an outer material grown onto the nanorods and further microstructural analysis by HR-STEM confirmed the development of core–shell structures in all cases. These studies also showed that the individual Al, Fe, Ni and Ti oxide layers are amorphous; an observation that matched with X-ray diffraction analysis where no apparent extra oxides were detected. For the multi-layered sample, the development of a shell consisting of three different oxide layers onto the nanorods was found. Overall results showed that no alteration in the primary ZnO core was produced during the growth of the shells, indicating that the deposition technique used herein was and it is suitable for the synthesis of homogeneous and complex nanomaterials high in quality and purity. In addition

  2. Single and multi-layered core-shell structures based on ZnO nanorods obtained by aerosol assisted chemical vapor deposition

    International Nuclear Information System (INIS)

    Core–shell nanorod structures were prepared by a sequential synthesis using an aerosol assisted chemical vapor deposition technique. Several samples consisting of ZnO nanorods were initially grown over TiO2 film-coated borosilicate glass substrates, following the synthesis conditions reported elsewhere. Later on, a uniform layer consisting of individual Al, Ni, Ti or Fe oxides was grown onto ZnO nanorod samples forming the so-called single MOx/ZnO nanorod core–shell structures, where MOx was the metal oxide shell. Additionally, a three-layer core–shell sample was developed by growing Fe, Ti and Fe oxides alternately, onto the ZnO nanorods. The microstructure of the core–shell materials was characterized by grazing incidence X-ray diffraction, scanning and transmission electron microscopy. Energy dispersive X-ray spectroscopy was employed to corroborate the formation of different metal oxides. X-ray diffraction outcomes for single core–shell structures showed solely the presence of ZnO as wurtzite and TiO2 as anatase. For the multi-layered shell sample, the existence of Fe2O3 as hematite was also detected. Morphological observations suggested the existence of an outer material grown onto the nanorods and further microstructural analysis by HR-STEM confirmed the development of core–shell structures in all cases. These studies also showed that the individual Al, Fe, Ni and Ti oxide layers are amorphous; an observation that matched with X-ray diffraction analysis where no apparent extra oxides were detected. For the multi-layered sample, the development of a shell consisting of three different oxide layers onto the nanorods was found. Overall results showed that no alteration in the primary ZnO core was produced during the growth of the shells, indicating that the deposition technique used herein was and it is suitable for the synthesis of homogeneous and complex nanomaterials high in quality and purity. In addition, materials absorptance determined from

  3. Controlling pyridinic, pyrrolic, graphitic, and molecular nitrogen in multi-wall carbon nanotubes using precursors with different N/C ratios in aerosol assisted chemical vapor deposition.

    Science.gov (United States)

    Bulusheva, L G; Okotrub, A V; Fedoseeva, Yu V; Kurenya, A G; Asanov, I P; Vilkov, O Y; Koós, A A; Grobert, N

    2015-10-01

    Nitrogen-containing multi-wall carbon nanotubes (N-MWCNTs) were synthesized using aerosol assisted chemical vapor deposition (CVD) techniques in conjunction with benzylamine:ferrocene or acetonitrile:ferrocene mixtures. Different amounts of toluene were added to these mixtures in order to change the N/C ratio of the feedstock. X-ray photoelectron and near-edge X-ray absorption fine structure spectroscopy detected pyridinic, pyrrolic, graphitic, and molecular nitrogen forms in the N-MWCNT samples. Analysis of the spectral data indicated that whilst the nature of the nitrogen-containing precursor has little effect on the concentrations of the different forms of nitrogen in N-MWCNTs, the N/C ratio in the feedstock appeared to be the determining factor. When the N/C ratio was lower than ca. 0.01, all four forms existed in equal concentrations, for N/C ratios above 0.01, graphitic and molecular nitrogen were dominant. Furthermore, higher concentrations of pyridinic nitrogen in the outer shells and N2 molecules in the core of the as-produced N-MWCNTs suggest that the precursors were decomposed into individual atoms, which interacted with the catalyst surface to form CN and NH species or in fact diffused through the bulk of the catalyst particles. These findings are important for a better understanding of possible growth mechanisms for heteroatom-containing carbon nanotubes (CNTs) and therefore paving the way for controlling the spatial distribution of foreign elements in the CNTs using CVD processes. PMID:26104737

  4. Effect of O2 gas partial pressure on mechanical properties of Al2O3 films deposited by inductively coupled plasma-assisted radio frequency magnetron sputtering

    International Nuclear Information System (INIS)

    The effect of O2 partial pressure on the mechanical properties of Al2O3 films is studied. Using films prepared by inductively coupled plasma-assisted radio frequency magnetron sputtering, the deposition rate of Al2O3 decreases rapidly when oxygen is added to the argon sputtering gas. The internal stresses in the films are compressive, with magnitude decreasing steeply from 1.6 GPa for films sputtered in pure argon gas to 0.5 GPa for films sputtered in argon gas at an O2 partial pressure of 0.89 × 10−2 Pa. Stress increases gradually with increasing O2 partial pressure. Using a nanoindentation tester with a Berkovich indenter, film hardness was measured to be about 14 GPa for films sputtered in pure argon gas. Hardness decreases rapidly on the addition of O2 gas, but increases when the O2 partial pressure is increased. Adhesion, measured using a Vickers microhardness tester, increases with increasing O2 partial pressure. Electron probe microanalyzer measurements reveal that the argon content of films decreases with increasing O2 partial pressure, whereas the O to Al composition ratio increases from 1.15 for films sputtered in pure argon gas to 1.5 for films sputtered in argon gas at O2 partial pressures over 2.4 × 10−2 Pa. X-ray diffraction measurements reveal that films sputtered in pure argon gas have an amorphous crystal structure, whereas γ-Al2O3 is produced for films sputtered in argon gas with added O2 gas. Atomic force microscopy observations reveal that the surface topography of sputtered Al2O3 films changes from spherical to needlelike as O2 partial pressure is increased. Fracture cross sections of the films observed by scanning electron microscopy reveal that the film morphology exhibits no discernible features at all O2 partial pressures.

  5. Nanodots and microwires of ZrO2 grown on LaAlO3 by photo-assisted metal-organic chemical vapor deposition

    Science.gov (United States)

    Feng, Guo; Xin-Sheng, Wang; Shi-Wei, Zhuang; Guo-Xing, Li; Bao-Lin, Zhang; Pen-Chu, Chou

    2016-02-01

    ZrO2 nanodots are successfully prepared on LaAlO3 (LAO) (100) substrates by photo-assisted metal-organic chemical vapor deposition (MOCVD). It is indicated that the sizes and densities of ZrO2 nanodots are controllable by modulating the growth temperature, oxygen partial pressure, and growth time. Meanwhile, the microwires are observed on the surfaces of substrates. It is found that there is an obvious competitive relationship between the nanodots and the microwires. In a growth temperature range from 500 °C to 660 °C, the microwires turn longest and widest at 600 °C, but in contrast, the nanodots grow into the smallest diameter at 600 °C. This phenomenon could be illustrated by the energy barrier, decomposition rate of Zr(tmhd)4, and mobility of atoms. In addition, growth time or oxygen partial pressure also affects the competitive relationship between the nanodots and the microwires. With increasing oxygen partial pressure from 451 Pa to 752 Pa, the microwires gradually grow larger while the nanodots become smaller. To further achieve the controllable growth, the coarsening effect of ZrO2 is modified by varying the growth time, and the experimental results show that the coarsening effect of microwires is higher than that of nanodots by increasing the growth time to quickly minimize ZrO2 energy density. Project supported by the National Natural Science Foundation of China (Grant No. 51002063) and the International Science and Technology Cooperation Program of Science and Technology Bureau of Changchun City, China (Grant No. 12ZX68).

  6. Friction and Wear Properties of Selected Solid Lubricating Films. Part 3; Magnetron-Sputtered and Plasma-Assisted, Chemical-Vapor-Deposited Diamondlike Carbon Films

    Science.gov (United States)

    Miyoshi, Kazuhisa; Iwaki, Masanori; Gotoh, Kenichi; Obara, Shingo; Imagawa, Kichiro

    2000-01-01

    To evaluate commercially developed dry solid film lubricants for aerospace bearing applications, an investigation was conducted to examine the friction and wear behavior of magnetron-sputtered diamondlike carbon (MS DLC) and plasma-assisted, chemical-vapor-deposited diamondlike carbon (PACVD DLC) films in sliding contact with 6-mm-diameter American Iron and Steel Institute (AISI) 440C stainless steel balls. Unidirectional sliding friction experiments were conducted with a load of 5.9 N (600 g), a mean Hertzian contact pressure of 0.79 GPa (maximum Hertzian contact pressure of L-2 GPa), and a sliding velocity of 0.2 m/s. The experiments were conducted at room temperature in three environments: ultrahigh vacuum (vacuum pressure, 7x10(exp -7) Pa), humid air (relative humidity, approx.20 percent), and dry nitrogen (relative humidity, films were characterized by scanning electron microscopy, energy-dispersive x-ray spectroscopy, and surface profilometry. Marked differences in the friction and wear of the DLC films investigated herein resulted from the environmental conditions. The main criteria for judging the performance of the DLC films were coefficient of friction and wear rate, which had to be less than 0.3 and on the order of 10(exp -6) cu mm/N-m or less, respectively. MS DLC films and PACVD DLC films met the criteria in humid air and dry nitrogen but failed in ultrahigh vacuum, where the coefficients of friction were greater than the criterion, 0.3. In sliding contact with 440C stainless steel balls in all three environments the PACVD DLC films exhibited better tribological performance (i.e., lower friction and wear) than the MS DLC films. All sliding involved adhesive transfer of wear materials: transfer of DLC wear debris to the counterpart 440C stainless steel and transfer of 440C stainless steel wear debris to the counterpart DLC film.

  7. Tuning the metal-insulator transition via epitaxial strain and Co doping in NdNiO{sub 3} thin films grown by polymer-assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Dan; Shi, Lei, E-mail: shil@ustc.edu.cn; Zhou, Shiming; Liu, Haifeng; Zhao, Jiyin; Li, Yang [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Wang, Yang [Instrumental Analysis Center, Hefei University of Technology, Hefei, Anhui 230009 (China)

    2016-01-21

    The epitaxial NdNi{sub 1-x}Co{sub x}O{sub 3} (0 ≤ x ≤ 0.10) thin films on (001) LaAlO{sub 3} and (001) SrTiO{sub 3} substrates were grown by a simple polymer-assisted deposition technique. The co-function of the epitaxial strain and Co doping on the metal-insulator transition in perovskite nickelate NdNiO{sub 3} thin films is investigated. X-ray diffraction and scanning electron microscopy reveal that the as-prepared thin films exhibit good crystallinity and heteroepitaxy. The temperature dependent resistivities of the thin films indicate that both the epitaxial strain and Co doping lower the metal-insulator (MI) transition temperature, which can be treated as a way to tune the MI transition. Furthermore, under the investigated Co-doping levels, the MI transition temperature (T{sub MI}) shifts to low temperatures with Co content increasing under both compressive and tensile strain, and the more distinction is in the former situation. When x is increased up to 0.10, the insulating phase is completely suppressed under the compressive strain. With the strain increases from compression to tension, the resistivities are enhanced both in the metal and insulating regions. However, the Co-doping effect on the resistivity shows a more complex situation. As Co content x increases from zero to 0.10, the resistivities are reduced both in the metal and insulating regions under the tensile strain, whereas they are enhanced in the high-temperature metal region under the compressive strain. Based on the temperature dependent resistivity in the metal regions, it is suggested that the electron-phonon coupling in the films becomes weaker with the increase of both the strain and Co-doping.

  8. Aerosol assisted chemical vapour deposition of gas sensitive SnO2 and Au-functionalised SnO2 nanorods via a non-catalysed vapour solid (VS) mechanism

    Science.gov (United States)

    Vallejos, Stella; Selina, Soultana; Annanouch, Fatima Ezahra; Gràcia, Isabel; Llobet, Eduard; Blackman, Chris

    2016-06-01

    Tin oxide nanorods (NRs) are vapour synthesised at relatively lower temperatures than previously reported and without the need for substrate pre-treatment, via a vapour-solid mechanism enabled using an aerosol-assisted chemical vapour deposition method. Results demonstrate that the growth of SnO2 NRs is promoted by a compression of the nucleation rate parallel to the substrate and a decrease of the energy barrier for growth perpendicular to the substrate, which are controlled via the deposition conditions. This method provides both single-step formation of the SnO2 NRs and their integration with silicon micromachined platforms, but also allows for in-situ functionalization of the NRs with gold nanoparticles via co-deposition with a gold precursor. The functional properties are demonstrated for gas sensing, with microsensors using functionalised NRs demonstrating enhanced sensing properties towards H2 compared to those based on non-functionalised NRs.

  9. Assistência de ar e volumes de aplicação na deposição de calda e no controle do arroz vermelho (Oryza sativa L. Air assistance and volume of application in spray deposition and in red rice control (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Leopoldo L. S. Vigano

    2007-12-01

    Full Text Available O trabalho teve como objetivo avaliar o efeito da assistência de ar junto à barra pulverizadora e de três volumes de pulverização na dessecação e deposição da calda em arroz vermelho, sob cultivo de nabo forrageiro, em áreas de recuperação de várzeas, utilizando o herbicida paraquat e o corante Azul Brilhante, respectivamente. Os volumes de pulverização foram 100; 200 e 300 L ha-1 da solução aquosa, contendo corante alimentício (1.500 mg L-1. Com ou sem a assistência de ar junto à barra, foram utilizadas pontas de pulverização de jato plano tipo AXI 110015 à pressão de 117,3 kPa, AXI 11002 e AXI 11003 a 276 kPa. A avaliação da deposição da pulverização deu-se em folhas de plantas de arroz vermelho. Os maiores volumes (200 e 300 L ha-1 pulverizados com a assistência de ar junto à barra pulverizadora proporcionaram maiores depósitos do corante em relação ao volume de 100 L ha-1. Não foram constatadas diferenças na deposição do corante para os volumes pulverizados, sem a assistência de ar junto à barra, tampouco entre os volumes de 200 e 300 L ha-1 com a assistência de ar junto à barra. As maiores percentagens de controle do arroz vermelho foram obtidas com a assistência de ar junto à barra, independentemente do volume pulverizado, equivalendo-se ao controle obtido com 300 L ha-1, sem o uso dessa tecnologia.The aim of this research was to evaluate the effect of air-assistance on spraying at three volumes in spray deposition and control of red rice under fodder radish cultivation. To evaluate the control of this weed and spray deposition were used paraquat herbicide and a Brilliant Blue dye, respectively. The three spraying volumes were 100, 200 and 300 L ha-1, using a tracer dye at 1,500 mg L-1. Both solutions and volumes were sprayed with flat fan nozzles AXI 110015 at 117.3 kPa, AXI 11002 and AXI 11003 at 276 kPa, respectively, with and without air-assistance on the boom. The evaluation of deposition

  10. Comparison of trimethylgallium and triethylgallium as “Ga” source materials for the growth of ultrathin GaN films on Si (100) substrates via hollow-cathode plasma-assisted atomic layer deposition

    International Nuclear Information System (INIS)

    GaN films grown by hollow cathode plasma-assisted atomic layer deposition using trimethylgallium (TMG) and triethylgallium (TEG) as gallium precursors are compared. Optimized and saturated TMG/TEG pulse widths were used in order to study the effect of group-III precursors. The films were characterized by grazing incidence x-ray diffraction, atomic force microscopy, x-ray photoelectron spectroscopy, and spectroscopic ellipsometry. Refractive index follows the same trend of crystalline quality, mean grain, and crystallite sizes. GaN layers grown using TMG precursor exhibited improved structural and optical properties when compared to GaN films grown with TEG precursor

  11. Comparison of trimethylgallium and triethylgallium as “Ga” source materials for the growth of ultrathin GaN films on Si (100) substrates via hollow-cathode plasma-assisted atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Alevli, Mustafa, E-mail: mustafaalevli@marmara.edu.tr [Department of Physics, Marmara University, Göztepe Kadıköy, 34722 İstanbul (Turkey); Haider, Ali; Kizir, Seda; Leghari, Shahid A.; Biyikli, Necmi, E-mail: biyikli@unam.bilkent.edu.tr [Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent, 06800 Ankara, Turkey and National Nanotechnology Research Center (UNAM), Bilkent University, Bilkent, 06800 Ankara (Turkey)

    2016-01-15

    GaN films grown by hollow cathode plasma-assisted atomic layer deposition using trimethylgallium (TMG) and triethylgallium (TEG) as gallium precursors are compared. Optimized and saturated TMG/TEG pulse widths were used in order to study the effect of group-III precursors. The films were characterized by grazing incidence x-ray diffraction, atomic force microscopy, x-ray photoelectron spectroscopy, and spectroscopic ellipsometry. Refractive index follows the same trend of crystalline quality, mean grain, and crystallite sizes. GaN layers grown using TMG precursor exhibited improved structural and optical properties when compared to GaN films grown with TEG precursor.

  12. Ferroelectric and ferromagnetic properties of epitaxial BiFeO{sub 3}-BiMnO{sub 3} films on ion-beam-assisted deposited TiN buffered flexible Hastelloy

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, J., E-mail: jiexiong@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Los Alamos National Laboratory, Center for Integrated Nanotechnologies, Division of Materials Physics and Applications, Los Alamos, New Mexico 87545 (United States); Matias, V.; Jia, Q. X. [Los Alamos National Laboratory, Center for Integrated Nanotechnologies, Division of Materials Physics and Applications, Los Alamos, New Mexico 87545 (United States); Tao, B. W.; Li, Y. R. [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2014-05-07

    Growth of multifunctional thin films on flexible substrates is of great technological significance since such a platform is needed for flexible electronics. In this study, we report the growth of biaxially aligned (BiFeO{sub 3}){sub 0.5}:(BiMnO{sub 3}){sub 0.5} [BFO-BMO] films on polycrystalline Hastelloy by using a biaxially aligned TiN as a seed layer deposited by ion-beam-assisted deposited and a La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) as a buffer layer deposited by pulsed laser deposition. The LSMO is used not only as a buffer layer but also as the bottom electrode of the BFO-BMO films. X-ray diffraction showed that the BFO-BMO films are biaxially oriented along both in-plane and out-of-plane directions. The BFO-BMO films on flexible metal substrates showed a polarization of 22.9 μC/cm{sup 2}. The magnetization of the BFO-BMO/LSMO is 62 emu/cc at room temperature.

  13. Influence of ion/atom arrival ratio on structure and optical properties of AlN films by ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-10-30

    Highlights: • AlN films were fabricated by dual ion beam sputtering. • Chemical bond status and phase composition of the films were studied by XPS and XRD. • Optical constants were measured by spectroscopic ellipsometry. • Influence of ion/atom arrival ratio on the films was studied. - Abstract: In order to improve the optical properties of AlN films, the influence of the ion/atom arrival ratio on the structure and optical characteristics of AlN films deposited by dual ion beam sputtering was studied by using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, spectroscopic ellipsometry and UV–vis spectroscopy. The films prepared at the ion/atom arrival ratio of 1.4 are amorphous while the crystalline quality is improved with the increase of the ion/atom arrival ratio. The films deposited at the ion/atom arrival ratio of no less than 1.8 have an approximately stoichiometric ratio and mainly consist of aluminum nitride with little aluminum oxynitride, while metallic aluminum component appears in the films deposited at the ion/atom arrival ratio of 1.4. When the ion/atom arrival ratio is not less than 1.8, films are smooth, high transmitting and dense. The films prepared with high ion/atom arrival ratio (≥1.8) display the characteristic of a dielectric. The films deposited at the ion/atom arrival ratio of 1.4 are coarse, opaque and show characteristic of cermet.

  14. Mathematical modeling for the composition prediction of compound films grown by ion-assisted deposition technique and its application to TiN x film

    Science.gov (United States)

    Kim, Jae-Keun; Colligon, J. S.; Jeong, Sang-Hun

    2004-10-01

    A simple general model has been formulated to explain the composition of compound films during growth simultaneous with ion bombardment. The variables in this model are (a) the sticking probability of the background residual reactive gas in the film, (b) an ion-enhanced sticking probability of these reactive gases arising from ion-enhanced adsorption and mixing and (c) ion implantation of the energetic ions impinging on the growing film. Preferential sputtering of various components in the film is also taken into account. The model is shown to be successful in explaining the experimental variations in the composition of TiN x films produced by ion-assisted growth.

  15. Screw-Dislocation-Driven Growth of Two-Dimensional Few-Layer and Pyramid-Like WSe2 by Sulfur-Assisted Chemical Vapor Deposition

    OpenAIRE

    Chen, Liang; Liu, Bilu; Abbas, Ahmad N.; Ma, Yuqiang; Fang, Xin; Liu, Yihang; Zhou, Chongwu

    2014-01-01

    Two-dimensional (2D) layered tungsten diselenides (WSe2) material has recently drawn a lot of attention due to its unique optoelectronic properties and ambipolar transport behavior. However, direct chemical vapor deposition (CVD) synthesis of 2D WSe2 is not as straightforward as other 2D materials due to the low reactivity between reactants in WSe2 synthesis. In addition, the growth mechanism of WSe2 in such CVD process remains unclear. Here we report the observation of a screw-dislocation-dr...

  16. Significant improvements of the high-field properties of carbon-doped MgB2 films by hot-filament-assisted hybrid physical-chemical vapor deposition using methane as the doping source

    International Nuclear Information System (INIS)

    We report a significant enhancement in upper critical field Hc2 and irreversibility field Hirr in carbon-doped MgB2 films fabricated by hot-filament-assisted hybrid physical-chemical vapor deposition (HFA-HPCVD) using methane as the doping source. For the parallel field, a very large temperature derivative -dHc2parallelab/dT value of 3 T K-1 near Tc was achieved in a heavily doped film with Tc near 28 K. Carbon doping also enhanced flux pinning, resulting in a much higher critical current density in a magnetic field Jc(H) than in undoped samples. The result suggests a more effective doping of carbon into the MgB2 structure and a better connectivity between the carbon-doped MgB2 grains than in previous reports. A clear correlation between the decrease in grain size and the enhancement of Hc2 was observed. (rapid communication)

  17. Optical properties and durability performance of substance SiO2/Nb2O5 for multilayer thin films prepared by high-density plasma-assisted vapor deposition

    Science.gov (United States)

    Moriizumi, Yasushi; Honma, Hideo; Takai, Osamu

    2016-01-01

    Optical lenses normally require an antireflection (AR) film to improve their characteristics of visibility and transmittance. The AR film is constructed with materials of various refractive indices and designed to obtain good optical properties by combining various materials to utilize light interference with controlled film thickness and number of layers. Therefore, in this study, we have fabricated an AR film consisting of multilayer thin films of SiO2 and Nb2O5 by high-density plasma-assisted vapor deposition to improve its environmental resistance, especially its mechanical properties, while maintaining its optical properties. We conducted the sand falling test to evaluate the damage to the multilayer we fabricated and found that the Nb2O5 layer located at a depth of about 200 nm from the outermost layer was plastically deformed and the layer absorbed the shock from the sand to reduce damage.

  18. Chemistry, phase formation, and catalytic activity of thin palladium-containing oxide films synthesized by plasma-assisted physical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2010-11-26

    The chemistry, microstructure, and catalytic activity of thin films incorporating palladium were studied using scanning and transmission electron microscopies, X-ray diffraction, spectrophotometry, 4-point probe and catalytic tests. The films were synthesized using pulsed filtered cathodic arc and magnetron sputter deposition, i.e. techniques far from thermodynamic equilibrium. Catalytic particles were formed by thermally cycling thin films of the Pd-Pt-O system. The evolution and phase formation in such films as a function of temperature were discussed in terms of the stability of PdO and PtO2 in air. The catalytic efficiency was found to be strongly affected by the chemical composition, with oxidized palladium definitely playing a major role in the combustion of methane. Reactive sputter deposition of thin films in the Pd-Zr-Y-O system allowed us forming microstructures ranging from nanocrystalline zirconia to palladium nanoparticles embedded in a (Zr,Y)4Pd2O matrix. The sequence of phase formation is put in relation to simple thermodynamic considerations.

  19. Effect of nitrogen surrounding gas and plasma assistance on nitrogen incorporation in a-C:N films by femtosecond pulsed laser deposition

    Science.gov (United States)

    Bourquard, F.; Maddi, C.; Donnet, C.; Loir, A.-S.; Barnier, V.; Wolski, K.; Garrelie, F.

    2016-06-01

    In the context of nitrogen-rich amorphous carbon thin films ultrafast pulsed laser deposition from graphite targets in inert nitrogen or nitrogen plasma ambient, this study assesses the correlation between the ablation plume composition and dynamics and the thin films contents and structures. The use of both optical emission spectroscopy and spectrally resolved 2D imaging, coupled with intensified CCD temporal resolution, allows to precisely follow such species of the plume as CN and C2 molecules, from their apparition to their deposition on the substrate. The results show that carbon-nitrogen bonding arises at the early time of expansion with little changes in quantity thereafter. The key role of the DC-bias is in lowering the molecular weight of the ambient gas, thus easing molecules way toward the target and interfering with the chemical reaction for CN generation. Depending on the ambient pressure, these processes will have drastically different effects on the thin films properties and contents. This work thus explains the origin of high nitrogen contents in a-C:N thin films obtained using DC-bias, and proposes an easy in situ optical observation-based way to predict and look for the best conditions to maximize those contents in future work.

  20. AAO-assisted synthesis of highly ordered, large-scale TiO2 nanowire arrays via sputtering and atomic layer deposition.

    Science.gov (United States)

    Yao, Zhao; Wang, Cong; Li, Yang; Kim, Nam-Young

    2015-01-01

    Highly ordered nanoporous anodic aluminum oxide (AAO) thin films were fabricated in oxalic acid under a constant voltage via a two-step anodization process. To investigate the high-aspect-ratio (7.5:1) filling process, both sputtering and atomic layer deposition (ALD) were used to form TiO2 nanowires. Field emission scanning electron microscopy and high-resolution transmission electron microscopy images indicated that mushroom-like TiO2 structures were sputtered onto the AAO template surface, and the ALD-coated TiO2 exhibited fine filling results and clear crystal grain boundaries. Large-scale and free-standing TiO2 nanowire arrays were liberated by selectively removing the aluminum substrate and AAO template via a wet etching process with no collapsing or agglomeration after the drying process. ALD-deposited TiO2 nanowire arrays that were 67 nm in diameter and 400 nm high were transferred from the AAO template. The ALD process enabled the rapid, simple synthesis of highly ordered TiO2 nanowire arrays with desired parameters such as diameter, density, and thickness determined using diverse AAO templates.

  1. The Effects of Annealing and Discharging on the Characteristics of MgO Thin Films Prepared by Ion Beam-Assisted Deposition as a Protective Layer of AC-PDP

    Institute of Scientific and Technical Information of China (English)

    YU Zhinong; SUN Jian; XUE Wei; ZHENG Dexiu

    2007-01-01

    This study investigated the effects of annealing and discharging on the characteristics of MgO thin films prepared by ion beam-assisted deposition as a protective layer of AC-PDP. By an annealing process at a temperature of 450 °C for more than three hours, the crystallinity of the deposited MgO films was improved, but the surface of the (200)-oriented MgO thin films in the vicinity of the discharge electrodes, especially on the inner sides of the electrodes, was subjected to crack formation. The failure mechanism of the (200)-oriented MgO films was due to the compressive stress of MgO films plus the additional compressive stress induced by the differences in the coefficient of thermal expansion between the electrode and the dielectric layer. In the discharging process, all MgO films were eroded unevenly, and the serious erosion occurred near the edges of the discharge electrodes. ATM(atomic force microscopy) images show that the eroded surface of the (200)-oriented MgO thin film is smoother than that of the (lll)-oriented film. Also, the (200)-oriented MgO thin film shows an improved ability to resist ion erosion compared to the (lll)-oriented film.

  2. Self-archiving to Institutional Repositories Is Improved by Assisted and Mandated Deposit; Disciplinary Culture is not a Factor. A Review of: Xia, Jingfeng. “Assessment of Self-Archiving in Institutional Repositories: Across Disciplines.” The Journal of Academic Librarianship 33.6 (Dec. 2007: 647-54.

    Directory of Open Access Journals (Sweden)

    Gaby Haddow

    2008-06-01

    subjected to further analysis. Using an “average publications per year” calculation for each discipline (from a 1977 paper, a final weighted rate of depositing was calculated for the four disciplines in the seven IRs. Main Results – Without weighting for faculty size, deposit rates vary greatly between disciplines. In most institutions, deposit rates for chemistry and sociology were higher than rates for physics and economics. When faculty size is controlled for, the highest deposit rates in five IRs were for chemistry and sociology. Only two IRs were found to have the highest deposit rates for physics and economics. These results did not change overall when the weighting for publishing productivity was applied: the same five IRs had highest deposit rates for chemistry and sociology. Exceptions to these findings were the IRs at University of Melbourne and University of Queensland, where the highest deposit rates were for economics and physics. On examination of depositor information, it was found that only 2.3% of economics deposits in the Melbourne IR were self-archived. Administrative assistants and other staffwere responsible for depositing 97.7% of the IR’s economics holdings. Self-archiving of physics items to the Melbourne IR was 90%; however, these deposits comprised student theses and dissertations only. Self-archiving practices were examined for:chemistry, physics and economics deposits at the University of Melbourne; chemistry and economics at the University of Queensland; and chemistry, physics and sociology at Queensland University ofTechnology (the only IR in the sample with a mandatory deposit policy. Like Melbourne, self-archiving of economics deposits at the University of Queensland was also low, at 17%. Of the remaining economics deposits, a librarian was responsible for depositing 68%. Chemistry deposits at both Melbourne and Queensland had much higher self-archiving rates, 76.2% and 100% respectively, than those found for physics and economics. At

  3. Size-controllable synthesis of Bi/Bi2O3 heterojunction nanoparticles using pulsed Nd:YAG laser deposition and metal-semiconductor-heterojunction-assisted photoluminescence

    Science.gov (United States)

    Patil, Ranjit A.; Wei, Mao-Kuo; Yeh, P.-H.; Liang, Jyun-Bo; Gao, Wan-Ting; Lin, Jin-Han; Liou, Yung; Ma, Yuan-Ron

    2016-02-01

    We synthesized Bi/Bi2O3 heterojunction nanoparticles at various substrate temperatures using the pulsed laser deposition (PLD) technique with a pulsed Nd:YAG laser. The Bi/Bi2O3 heterojunction nanoparticles consisted of Bi nanoparticles and Bi2O3 surface layers. The average diameter of the Bi nanoparticles and the thickness of the Bi2O3 surface layer are linearly proportional to the substrate temperature. The heterojunctions between the Bi nanoparticles and Bi2O3 surface layers, which are the metal-semiconductor heterojunctions, can strongly enhance the photoluminescence (PL) of the Bi/Bi2O3 nanoparticles, because the metallic Bi nanoparticles can provide massive free Fermi-level electrons for the electron transitions in the Bi2O3 surface layers. The enhancement of PL emission at room temperature by metal-semiconductor-heterojunctions make the Bi/Bi2O3 heterojunction nanoparticles potential candidates for use in optoelectronic nanodevices, such as light-emitting diodes (LEDs) and laser diodes (LDs).We synthesized Bi/Bi2O3 heterojunction nanoparticles at various substrate temperatures using the pulsed laser deposition (PLD) technique with a pulsed Nd:YAG laser. The Bi/Bi2O3 heterojunction nanoparticles consisted of Bi nanoparticles and Bi2O3 surface layers. The average diameter of the Bi nanoparticles and the thickness of the Bi2O3 surface layer are linearly proportional to the substrate temperature. The heterojunctions between the Bi nanoparticles and Bi2O3 surface layers, which are the metal-semiconductor heterojunctions, can strongly enhance the photoluminescence (PL) of the Bi/Bi2O3 nanoparticles, because the metallic Bi nanoparticles can provide massive free Fermi-level electrons for the electron transitions in the Bi2O3 surface layers. The enhancement of PL emission at room temperature by metal-semiconductor-heterojunctions make the Bi/Bi2O3 heterojunction nanoparticles potential candidates for use in optoelectronic nanodevices, such as light-emitting diodes

  4. Determining the microwave coupling and operational efficiencies of a microwave plasma assisted chemical vapor deposition reactor under high pressure diamond synthesis operating conditions

    International Nuclear Information System (INIS)

    The microwave coupling efficiency of the 2.45 GHz, microwave plasma assisted diamond synthesis process is investigated by experimentally measuring the performance of a specific single mode excited, internally tuned microwave plasma reactor. Plasma reactor coupling efficiencies (η) > 90% are achieved over the entire 100–260 Torr pressure range and 1.5–2.4 kW input power diamond synthesis regime. When operating at a specific experimental operating condition, small additional internal tuning adjustments can be made to achieve η > 98%. When the plasma reactor has low empty cavity losses, i.e., the empty cavity quality factor is >1500, then overall microwave discharge coupling efficiencies (ηcoup) of >94% can be achieved. A large, safe, and efficient experimental operating regime is identified. Both substrate hot spots and the formation of microwave plasmoids are eliminated when operating within this regime. This investigation suggests that both the reactor design and the reactor process operation must be considered when attempting to lower diamond synthesis electrical energy costs while still enabling a very versatile and flexible operation performance

  5. Determining the microwave coupling and operational efficiencies of a microwave plasma assisted chemical vapor deposition reactor under high pressure diamond synthesis operating conditions

    Science.gov (United States)

    Nad, Shreya; Gu, Yajun; Asmussen, Jes

    2015-07-01

    The microwave coupling efficiency of the 2.45 GHz, microwave plasma assisted diamond synthesis process is investigated by experimentally measuring the performance of a specific single mode excited, internally tuned microwave plasma reactor. Plasma reactor coupling efficiencies (η) > 90% are achieved over the entire 100-260 Torr pressure range and 1.5-2.4 kW input power diamond synthesis regime. When operating at a specific experimental operating condition, small additional internal tuning adjustments can be made to achieve η > 98%. When the plasma reactor has low empty cavity losses, i.e., the empty cavity quality factor is >1500, then overall microwave discharge coupling efficiencies (ηcoup) of >94% can be achieved. A large, safe, and efficient experimental operating regime is identified. Both substrate hot spots and the formation of microwave plasmoids are eliminated when operating within this regime. This investigation suggests that both the reactor design and the reactor process operation must be considered when attempting to lower diamond synthesis electrical energy costs while still enabling a very versatile and flexible operation performance.

  6. Determining the microwave coupling and operational efficiencies of a microwave plasma assisted chemical vapor deposition reactor under high pressure diamond synthesis operating conditions.

    Science.gov (United States)

    Nad, Shreya; Gu, Yajun; Asmussen, Jes

    2015-07-01

    The microwave coupling efficiency of the 2.45 GHz, microwave plasma assisted diamond synthesis process is investigated by experimentally measuring the performance of a specific single mode excited, internally tuned microwave plasma reactor. Plasma reactor coupling efficiencies (η) > 90% are achieved over the entire 100-260 Torr pressure range and 1.5-2.4 kW input power diamond synthesis regime. When operating at a specific experimental operating condition, small additional internal tuning adjustments can be made to achieve η > 98%. When the plasma reactor has low empty cavity losses, i.e., the empty cavity quality factor is >1500, then overall microwave discharge coupling efficiencies (η(coup)) of >94% can be achieved. A large, safe, and efficient experimental operating regime is identified. Both substrate hot spots and the formation of microwave plasmoids are eliminated when operating within this regime. This investigation suggests that both the reactor design and the reactor process operation must be considered when attempting to lower diamond synthesis electrical energy costs while still enabling a very versatile and flexible operation performance.

  7. Depósito e perdas de calda em sistema de pulverização com turboatomizador em videira Deposition and spray losses in an air-assisted sprayer system in grapevine

    Directory of Open Access Journals (Sweden)

    Marcelo G. Balan

    2006-08-01

    Full Text Available Grande parte dos viticultores da região Norte do Paraná pratica a condução da videira em caramanchão, com mais de 50 aplicações fitossanitárias em um único ciclo. O objetivo deste trabalho foi avaliar essas aplicações com turboatomizador assistido de ar no sistema de pulverização, por meio do depósito de calda nas folhas e perdas. O trabalho foi desenvolvido utilizando-se de cinco condições de aplicação, variando-se tamanho de gotas e volume de aplicação, com quatro repetições, em blocos casualizados. A avaliação do sistema foi feita com a aplicação de uma calda de cloreto de potássio (5%, sendo o depósito nas folhas medido pela condutividade elétrica, e as perdas, pela comparação entre volumes aplicado e recuperado nas folhas. Para todas as condições, as perdas foram superiores a 48%. Os maiores volumes aplicados apresentaram as maiores deposições, e gotas maiores apresentaram maior depósito e mesma perda em relação a gotas menores. Os menores volumes não diferiram com relação à deposição, destacando-se as condições gotas maiores a volume baixo e a testemunha utilizada pelo viticultor, que apresentaram as menores perdas. Os resultados demonstram que o turboatomizador é uma importante ferramenta para maximizar as operações de pulverização em uva, e as alterações na configuração das pontas de pulverização devem ser mais estudadas.Winegrowers in the north of Paraná State carry on grapevines in arbour and pesticide applications could overcome more than fifty times in a cycle. The aim of this study was to evaluate the features of the air assisted sprayer application system by spray volume deposition and losses. Five treatments and four randomized blocks were used. The treatments varied the droplet size and application volume. The evaluation of the system was done with a 5% spray solution containing KCl being the leaves spray deposit measured through electric conductivity and the losses by the

  8. Structural effects due to the incorporation of Ar atoms in the lattice of ZrO sub 2 thin films prepared by ion beam assisted deposition

    CERN Document Server

    Holgado, J P; Veen, A V; Schut, H; Hosson, J T M; González-Elipe, A R

    2002-01-01

    Two sets of ZrO sub 2 thin films have been prepared at room temperature by ion beam induced chemical vapour deposition and subsequently annealed up to 1323 K. The two sets of samples have been prepared by using either O sub 2 sup + or mixtures of (O sub 2 sup + +Ar sup +) ions for the decomposition of a volatile metallorganic precursor of zirconium. The structure and microstructure of these two sets of samples have been determined by means of X-ray diffraction, Fourier transform infrared spectroscopy and positron beam analysis (PBA). The samples were very compact and dense and had a very low-surface roughness. After annealing in air at T>=573 K both sets of films were transparent and showed similar refraction indexes. For the (O sub 2 sup + +Ar sup +)-ZrO sub 2 thin films it is shown by X-ray photoelectron spectroscopy and Rutherford back scattering that a certain amount of incorporated Ar (5-6 at.%) remains incorporated within the oxide lattice. No changes were detected in the amount of incorporated Ar even ...

  9. Titania nanocoating on MnCO3 microspheres via liquid-phase deposition for fabrication of template-assisted core-shell- and hollow-structured composites.

    Science.gov (United States)

    Lee, Hack-Keun; Sakemi, Daisuke; Selyanchyn, Roman; Lee, Cheal-Gyu; Lee, Seung-Woo

    2014-01-01

    A novel class of core-shell- and hollow-structured MnCO3/TiO2 composites was synthesized by titania nanocoating on MnCO3 microspheres via two-step liquid-phase deposition at room temperature. Morphological change from core-shell to hollow microparticles was possible in the prepared samples by controlling prereaction time of MnCO3 and [NH4]2TiF6. Upon the prereaction process, the core of the core-shell MnCO3/TiO2 became highly porous, and a honeycomb-like surface that resembled the orientation of self-assembled MnCO3 nanocrystals was developed. The MnCO3 core was completely removed after 6 h prereaction. Calcination at 600 °C resulted in the transformation of both core-shell- and hollow-structured composites to Mn2O3/TiO2 anatase microspheres that retained their original morphologies. X-ray diffraction, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and electron probe microanalysis were employed for microsphere characterization. As the first trial for application of the synthesized materials, solid-extraction of organics from aqueous media was examined using methylene blue (MB). Both types of Mn2O3/TiO2 composites showed very fast adsorption of MB with high extraction values of 5.2 and 6.4 μmol g(-1) for the core-shell and hollow structures, respectively. Current work provides a new approach for facile fabrication of titania-metal oxide nanocomposites with unique morphological features and promising application possibilities. PMID:24320871

  10. Size-tuned ZnO nanocrucible arrays for magnetic nanodot synthesis via atomic layer deposition-assisted block polymer lithography.

    Science.gov (United States)

    Lin, Chun-Hao; Polisetty, Srinivas; O'Brien, Liam; Baruth, Andrew; Hillmyer, Marc A; Leighton, Chris; Gladfelter, Wayne L

    2015-02-24

    Low-temperature atomic layer deposition of conformal ZnO on a self-assembled block polymer lithographic template comprising well-ordered, vertically aligned cylindrical pores within a poly(styrene) (PS) matrix was used to produce nanocrucible templates with pore diameters tunable via ZnO thickness. Starting from a PS template with a hexagonal array of 30 nm diameter pores on a 45 nm pitch, the ZnO thickness was progressively increased to narrow the pore diameter to as low as 14 nm. Upon removal of the PS by heat treatment in air at 500 °C to form an array of size-tunable ZnO nanocrucibles, permalloy (Ni80Fe20) was evaporated at normal incidence, filling the pores and creating an overlayer. Argon ion beam milling was then used to etch back the overlayer (a Damascene-type process), leaving a well-ordered array of isolated ZnO nanocrucibles filled with permalloy nanodots. Microscopy and temperature-dependent magnetometry verified the diameter reduction with increasing ZnO thickness. The largest diameter (30 nm) dots exhibit a ferromagnetic multidomain/vortex state at 300 K, with relatively weakly temperature-dependent coercivity. Reducing the diameter leads to a crossover to a single-domain state and eventually superparamagnetism at sufficiently high temperature, in quantitative agreement with expectations. We argue that this approach could render this form of block polymer lithography compatible with high-temperature processing (as required for technologically important high perpendicular anisotropy ordered alloys, for instance), in addition to enabling separation-dependent studies to probe interdot magnetostatic interactions.

  11. MAPLE deposition of nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Caricato, A.P., E-mail: annapaola.caricato@le.infn.it [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Arima, V.; Catalano, M. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Cesaria, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Cozzoli, P.D. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Martino, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Taurino, A.; Rella, R. [Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, I-73100 Lecce (Italy); Scarfiello, R. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Tunno, T. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Zacheo, A. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy)

    2014-05-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  12. Magnetocaloric effect and temperature coefficient of resistance of La0.85Ag0.15MnO3 epitaxial thin films obtained by polymer-assisted deposition

    Directory of Open Access Journals (Sweden)

    Cobas Acosta R.

    2014-07-01

    Full Text Available We report the magnetocaloric effects and temperature coefficient of resistance (TCR of La0.85Ag0.15MnO3 epitaxial thin films grown on single-crystal substrates of LaAlO3 (001 and SrTiO3 (001 using the chemical solution approach of polymer-assisted deposition (PAD. The film thicknesses are in the range 30-35 nm. Magnetocaloric effects, with entropy changes of -2.14 J/kg.K, in the case of the LaAlO3 substrate and -2.72 J/kg.K for the SrTiO3 substrate, (corresponding to a magnetic field variation of 2T were obtained at room temperature. The refrigeration capacity at this field variation reached large values of 125 J/kg and 216 J/kg, indicating that these films prepared by PAD have the potential for microcooling applications. The temperature coefficient of resistance has been calculated from the resistivity measurements. A maximum TCR value of 3.01 % K-1 was obtained at 309 K, which shows that these films also have potential as uncooled thermometers for bolometric applications.

  13. Research on Atomic Layer Deposition of Alumina Thin Film with Plasma Assisted%等离子体辅助原子层沉积氧化铝薄膜的研究

    Institute of Scientific and Technical Information of China (English)

    桑利军; 赵桥桥; 胡朝丽; 李兴存; 雷雯雯; 陈强

    2012-01-01

    In order to achieve atomic layer deposition of alumina thin films at room temperature, taking trimethylaluminum (TMA) as the precursor and oxygen as the oxidant, respectively , we used an atomic layer deposition(PA-ALD) setup of homemade electron cyclotron resonance (ECR) assisted with plasma to deposit AI203 thin film on the single crystal silicon surface at room temperature. Through scanning electron microscope (SEM), atomic force microscope, high resolution transmission electron microscope, X-ray diffraction and X-ray photoelectric spectroscopy, the surface topography and composition of the as-deposited films were tested. It is found that the A12 03 films are amorphous, and the atomic ratio of aluminum to oxygen is close to 2/3. The film surface is very smooth and the roughness is smaller than 0.4 nm. The cross-sectional images show that the film thickness is 80 nm with specially clear and smooth interface, better film quality, and the deposition rate is 0.27 nm in one cycle, which is much larger than the thermal ALD.%为在室温条件下进行氧化铝薄膜的原子层沉积,自行设计了一套微波回旋共振等离子体辅助原子层沉积装置,以三甲基铝作为铝源前躯体,氧气作为氧化剂,在室温下于氢氟酸溶液中处理过的单晶硅基片上进行了氧化铝薄膜的沉积。利用扫描电子显微镜、原子力显微镜、高分辨率透射电子显微镜、X-ray射线衍射、X-ray射线光电子能谱等分析手段测试了薄膜的表面形貌和成分,结果表明制备的氧化铝薄膜为非晶态结构,铝、氧元素含量配比接近2/3,同时薄膜表面非常光滑平整而且致密,表面粗糙度<0.4nm。通过高分辨率透射电子显微镜的截面图,可以估算出薄膜厚度约为80nm,界面非常清晰、平整,薄膜质量较高,沉积速率为0.27nm/周期,沉积速率较热沉积大大提高。

  14. Assisted Living

    Science.gov (United States)

    ... overwhelming majority of residents are female. Assisted Living Philosophy The philosophy of assisted living is to provide personalized, resident ... loved ones to learn about the care provider philosophy . Freedom of Choice The most progressive state regulations ...

  15. Assistive Technology

    Science.gov (United States)

    ... Page Resize Text Printer Friendly Online Chat Assistive Technology Assistive technology (AT) is any service or tool that helps ... be difficult or impossible. For older adults, such technology may be a walker to improve mobility or ...

  16. Surgical Assisting

    Science.gov (United States)

    ... specific training over and above a degree in science, nursing, physician assisting, or another health profession. Prerequisites . Recommended eligibility requirements for admission into a surgical assisting program are: Bachelor of Science degree (or higher) Associate degree in an allied ...

  17. Ventricular assist device

    Science.gov (United States)

    VAD; RVAD; LVAD; BVAD; Right ventricular assist device; Left ventricular assist device; Biventricular assist device; Heart pump; Left ventricular assist system; LVAS; Implantable ventricular assist device

  18. United Nations programme for the assistance in Uruguay mining exploration

    International Nuclear Information System (INIS)

    The Uruguay government asked for the United Nations for the development of technical assistance programme in geological considerations of the Valentines iron deposits. This agreement was signed as Mining prospect ion assistance in Uruguay.

  19. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>20102406 Chen Gang(China University of Geosciences,Beijing 100083,China);Li Fengming Discussion on Geological Characteristics and Genesis of Yuquanshan Graphite Deposit of Xinjiang(Xinjiang Geology,ISSN1000-8845,CN65-1092/P,27(4),2009,p.325-329,4 illus.,4 tables,5 refs.)Key words:graphite deposit,XinjiangYuquanshan graphite deposit of Xinjiang occurs in mica-quartz schist of Xingeer Information which belongs to Xinditate Group of Lower Pt in Kuluketage Block of Tarim paleo-continent,and experiences two mineralizing periods of

  20. 24 CFR 891.775 - Security deposits.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Security deposits. 891.775 Section 891.775 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... Individuals-Section 162 Assistance § 891.775 Security deposits. The general requirements for security...

  1. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20140876 Gao Junbo(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China);Yang Ruidong Study on the Strontium Isotopic Composition of Large Devonian Barite Deposits from Zhenning,Guizhou Province(Geochimica,

  2. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>20122457 Cai Jianshe ( Fujian Institute of Geological Survey and Drawing,Fuzhou 350011,China ) On the Geologic Characteristics and Genesis of the Longtangsi Fluorite Deposit in Pucheng County,Fujian Province ( Geology of Fujian,ISSN1001-3970,CN35-1080 / P,30 ( 4 ), 2011,p.301-306,3illus.,1table,6 refs.,with English abstract ) Key words:fluorspar deposit,Fujian Province

  3. Assisted Ventilation.

    Science.gov (United States)

    Dries, David J

    2016-01-01

    Controlled Mechanical Ventilation may be essential in the setting of severe respiratory failure but consequences to the patient including increased use of sedation and neuromuscular blockade may contribute to delirium, atelectasis, and diaphragm dysfunction. Assisted ventilation allows spontaneous breathing activity to restore physiological displacement of the diaphragm and recruit better perfused lung regions. Pressure Support Ventilation is the most frequently used mode of assisted mechanical ventilation. However, this mode continues to provide a monotonous pattern of support for respiration which is normally a dynamic process. Noisy Pressure Support Ventilation where tidal volume is varied randomly by the ventilator may improve ventilation and perfusion matching but the degree of support is still determined by the ventilator. Two more recent modes of ventilation, Proportional Assist Ventilation and Neurally Adjusted Ventilatory Assist (NAVA), allow patient determination of the pattern and depth of ventilation. Proposed advantages of Proportional Assist Ventilation and NAVA include decrease in patient ventilator asynchrony and improved adaptation of ventilator support to changing patient demand. Work of breathing can be normalized with these modes as well. To date, however, a clear pattern of clinical benefit has not been demonstrated. Existing challenges for both of the newer assist modes include monitoring patients with dynamic hyperinflation (auto-positive end expiratory pressure), obstructive lung disease, and air leaks in the ventilator system. NAVA is dependent on consistent transduction of diaphragm activity by an electrode system placed in the esophagus. Longevity of effective support with this technique is unclear. PMID:25501776

  4. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20110947 Chen Xinglong(Guizhou Bureau of Nonferrous Metal and Nuclear Geology,Guiyang 550005,China);Gong Heqiang Endowment Factors and Development & Utilization Strategy of Bauxite Resource in North Guizhou Province(Guizhou Geology,ISSN1000-5943,CN52-1059/P,27(2),2010,p.106-110,6 refs.,with English abstract)Key words:bauxite deposit,Guizhou Province20110948 Dang Yanxia(Mineral Resource & Reservoir Evaluation Center,Urumiq 830000,China);Fan Wenjun Geological Features and a Primary Study of Metallogenesis of the Wucaiwang Zeolite Deposit,Fuyun County(Xinjiang Geology,ISSN1000-8845,CN65-1092/P,28(2),2010,p.167-170,2 illus.,1 table,5 refs.)Key words:zeolite deposit,Xinjiang Nearly all zeolite deposits in the world result from low-temperature-alteration of glass-bearing volcanic rocks.The southern slope of the Kalamali Mountain is one of the regions where medium to acid volcanics are major lithological type,thus it is a preferred area to look for zeolite deposit.The Wucaiwang zeolite ore district consists of mainly acid volcanic-clastic rocks.

  5. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091594 Bao Yafan(The Third Geologic Survey of Jilin Province,Siping 136000,China);Liu Yanjun Relations between Bashenerxi Granite,West Dongkunlun and Baiganhu Tungsten-Tin Deposit(Jilin Geology,ISSN1001-2427,CN22-1099/P,27(3),2008,p.56-59,67,5 illus.,2 tables,7 refs.,with English abstract)Key words:tungsten ores,tin ores,monzogranite,Kunlun Mountains20091595 Chen Fuwen(Yichang Institute of Geology and Mineral Resources,China Geological Survey,Yichang 443003,China);Dai Pingyun Metallogenetic and Isotopic Chronological Study on the Shenjiaya Gold Deposit in Xuefeng Mountains,Hunan Province(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,82(7),2008,p.906-911,3 illus.,2 tables,30 refs.)Key words:gold ores,HunanThe Shenjiaya gold deposit is a representative one

  6. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111705 An Junbo(Team 603,Bureau of Nonferrous Metals Geological Exploration of Jilin Province,Hunchun 133300,China);Xu Renjie Geological Features and Ore Genesis of Baishilazi Scheelite Deposit in Yanbian Area(Jilin Geology,ISSN1001-2427,CN22-1099/P,29(3),2010,p.39-43,2 illus.,2 tables,7 refs.)Key words:tungsten ores,Jilin ProvinceThe Baishilazi scheelite deposit is located in contacting zone between the marble of the Late Palaeozoic Qinglongcun Group and the Hercynian biotite granite.The vein and lenticular major ore body is obviously controlled by NE-extending faults and con

  7. Thin films of hydrogenated amorphous carbon (a-C:H) obtained through chemical vapor deposition assisted by plasma; Peliculas delgadas de carbono amorfo hidrogenado (a-C:H) obtenidas mediante deposito quimico de vapores asistido por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Mejia H, J.A.; Camps C, E.E.; Escobar A, L.; Romero H, S.; Chirino O, S. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Muhl S, S. [IIM-UNAM, 04510 Mexico D.F. (Mexico)

    2004-07-01

    Films of hydrogenated amorphous carbon (a-C:H) were deposited using one source of microwave plasma with magnetic field (type ECR), using mixtures of H{sub 2}/CH{sub 4} in relationship of 80/20 and 95/05 as precursory gases, with work pressures of 4X10{sup -4} to 6x10{sup -4} Torr and an incident power of the discharge of microwaves with a constant value of 400 W. It was analyzed the influence among the properties of the films, as the deposit rate, the composition and the bonding types, and the deposit conditions, such as the flow rates of the precursory gases and the polarization voltage of the sample holders. (Author)

  8. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131565 Cai Lianyou(No.332 Geological Team,Bureau of Geology and Mineral Resources Exploration of Anhui Province,Huangshan 245000,China);Weng Wangfei Geological Characteristics and Genesis Analysis of Guocun Navajoite Deposit in South Anhui Province(Mineral Resources and Geology,

  9. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>20102341 Bao Peisheng(Institute of Geology,Chinese Academy of Geological Science,Beijing 100037,China)Further Discussion on the Genesis of the Podiform Chromite Deposits in the Ophiolites-Questioning about the Rock:Melt Interaction Metallogeny(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,28(12),2009,p.1741-1761

  10. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131601 Gao Junbo(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550003,China);Yang Ruidong Hydrothermal Venting-Flowing Sedimentation Characteristics of Devonian Barite Deposits from Leji,Zhenning County,Guizhou Province(Acta Sedimentologica Sinica,ISSN1000-0550,CN62-1038/P,30(3),

  11. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20150904An Fang(State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,China);Wang Juli Skarn Mineral Assemblage in Representative Ore Districts of Sayak Copper Orefield,Kazakhstan,and Its Genetic Implications(Mineral Deposits,ISSN0258-7106,CN11-1965/P,33(3),2014,p.521-540,

  12. Hearing Assistive Technology

    Science.gov (United States)

    ... for the Public / Hearing and Balance Hearing Assistive Technology Hearing Assistive Technology: FM Systems | Infrared Systems | Induction ... Assistive Technology Systems Solutions What are hearing assistive technology systems (HATS)? Hearing assistive technology systems (HATS) are ...

  13. Enhancement of Low-field Magnetoresistance in Self-Assembled Epitaxial La0.67Ca0.33MnO3:NiO and La0.67Ca0.33MnO3:Co3O4 Composite Films via Polymer-Assisted Deposition.

    Science.gov (United States)

    Zhou, Meng; Li, Yuling; Jeon, Il; Yi, Qinghua; Zhu, Xuebin; Tang, Xianwu; Wang, Haiyan; Fei, Ling; Sun, Yuping; Deng, Shuguang; Matsuo, Yutaka; Luo, Hongmei; Zou, Guifu

    2016-01-01

    Polymer-assisted deposition method has been used to fabricate self-assembled epitaxial La0.67Ca0.33MnO3:NiO and La0.67Ca0.33MnO3:Co3O4 films on LaAlO3 substrates. Compared to pulsed-laser deposition method, polymer-assisted deposition provides a simpler and lower-cost approach to self-assembled composite films with enhanced low-field magnetoresistance effect. After the addition of NiO or Co3O4, triangular NiO and tetrahedral Co3O4 nanoparticles remain on the surface of La0.67Ca0.33MnO3 films. This results in a dramatic increase in resistivity of the films from 0.0061 Ω•cm to 0.59 Ω•cm and 1.07 Ω•cm, and a decrease in metal-insulator transition temperature from 270 K to 180 K and 172 K by the addition of 10%-NiO and 10%-Co3O4, respectively. Accordingly, the maximum absolute magnetoresistance value is improved from -44.6% to -59.1% and -52.7% by the addition of 10%-NiO and 10%-Co3O4, respectively. The enhanced low-field magnetoresistance property is ascribed to the introduced insulating phase at the grain boundaries. The magnetism is found to be more suppressed for the La0.67Ca0.33MnO3:Co3O4 composite films than the La0.67Ca0.33MnO3:NiO films, which can be attributed to the antiferromagnetic properties of the Co3O4 phase. The solution-processed composite films show enhanced low-field magnetoresistance effect which are crucial in practical applications. We expect our polymer-assisted deposited films paving the pathway in the field of hole-doped perovskites with their intrinsic colossal magnetoresistance. PMID:27381661

  14. Deposition of thin layers of boron nitrides and hydrogenated microcrystalline silicon assisted by high current direct current arc plasma; Deposition assistee par un plasma a arc a haut courant continu de couches minces de Nitrure de Bore et de Silicium microcristallin hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Franz, D. [Ecole Polytechnique Federale de Lausanne, Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne (Switzerland)

    1999-09-01

    In the frame of this thesis, a high current direct current arc (HCDCA) used for the industrial deposition of diamond, has been adapted to study the deposition of two types of coatings: a) boron nitride, whose cubic phase is similar to diamond, for tribological applications, b) hydrogenated microcrystalline silicon, for applications in the semiconductor fields (flat panel displays, solar cells,...). For the deposition of these coatings, the substrates were placed in the diffusion region of the arc. The substrate heating is mainly due to atomic species recombining on its surface. The deposition temperature, varying from 300 to 900 {sup o}C according to the films deposited, is determined by the substrate position, the arc power and the injected gas fluxes, without the use of any external heating or cooling system. Measurements performed on the arc plasma show that the electronic temperature is around 2 eV (23'000 K) while the gas temperature is lower than 5500 K. Typical electronic densities are in the range of 10{sup 12}-10{sup 1'}3 cm{sup -3}. For the deposition of boron nitride films, different boron precursors were used and a wide parameter range was investigated. The extreme difficulty of synthesising cubic boron nitride films by chemical vapour deposition (CVD) did not allow to stabilize the cubic phase of boron nitride in HCDCA. Coatings resulted in hexagonal or amorphous boron nitride with a chemical composition close to stoichiometric. The presence of hydrogen leads to the deposition of rough and porous films. Negative biasing of the samples, for positive ion bombardment, is commonly used to stabilize the cubic phase. In HCDCA and in our biasing range, only a densification of the films could be observed. A boron nitride deposition plasma study by infrared absorption spectroscopy in a capacitive radio frequency reactor has demonstrated the usefulness of this diagnostic for the understanding of the various chemical reactions which occur in this kind

  15. Structural characterization of MAPLE deposited lipase biofilm

    International Nuclear Information System (INIS)

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase

  16. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  17. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111761 Chen Hua(115 Geological Party,Guizhou Bureau of Geology and Mineral Exploration & Development,Guiyang 551400,China);Deng Chao Analysis on the Metallogenic Environment of Maochang Bauxite in Guizhou Province(Guizhou Geology,ISSN1000-5943,CN52-1059/P,27(3),2010,p.198-201,2 illus.,1 table,8 refs.)Key words:bauxite deposit,Guizhou Province By long time physical and chemical process,the carbonate rock after Central Guizhou uplidft,becomes red clay,after further weathering,the red clay decomposed into the oxide,hydroxide of Al and Fe,in the dissolution hole and depression,it concentrates primary fragmentary tight and earthy karst bauxite ore.Because the variation of landform,it decomposes and cracks again,affords the material source

  18. Template-assisted synthesis of III-nitride and metal-oxide nano-heterostructures using low-temperature atomic layer deposition for energy, sensing, and catalysis applications (Presentation Recording)

    Science.gov (United States)

    Biyikli, Necmi; Ozgit-Akgun, Cagla; Eren, Hamit; Haider, Ali; Uyar, Tamer; Kayaci, Fatma; Guler, Mustafa Ozgur; Garifullin, Ruslan; Okyay, Ali K.; Ulusoy, Gamze M.; Goldenberg, Eda

    2015-08-01

    Recent experimental research efforts on developing functional nanostructured III-nitride and metal-oxide materials via low-temperature atomic layer deposition (ALD) will be reviewed. Ultimate conformality, a unique propoerty of ALD process, is utilized to fabricate core-shell and hollow tubular nanostructures on various nano-templates including electrospun nanofibrous polymers, self-assembled peptide nanofibers, metallic nanowires, and multi-wall carbon nanotubes (MWCNTs). III-nitride and metal-oxide coatings were deposited on these nano-templates via thermal and plasma-enhanced ALD processes with thickness values ranging from a few mono-layers to 40 nm. Metal-oxide materials studied include ZnO, TiO2, HfO2, ZrO2, and Al2O3. Standard ALD growth recipes were modified so that precursor molecules have enough time to diffuse and penetrate within the layers/pores of the nano-template material. As a result, uniform and conformal coatings on high-surface area nano-templates were demonstrated. Substrate temperatures were kept below 200C and within the self-limiting ALD window, so that temperature-sensitive template materials preserved their integrity III-nitride coatings were applied to similar nano-templates via plasma-enhanced ALD (PEALD) technique. AlN, GaN, and InN thin-film coating recipes were optimized to achieve self-limiting growth with deposition temperatures as low as 100C. BN growth took place only for >350C, in which precursor decomposition occured and therefore growth proceeded in CVD regime. III-nitride core-shell and hollow tubular single and multi-layered nanostructures were fabricated. The resulting metal-oxide and III-nitride core-shell and hollow nano-tubular structures were used for photocatalysis, dye sensitized solar cell (DSSC), energy storage and chemical sensing applications. Significantly enhanced catalysis, solar efficiency, charge capacity and sensitivity performance are reported. Moreover, core-shell metal-oxide and III-nitride materials

  19. Mixed-Halide CH3 NH3 PbI3-x Xx (X=Cl, Br, I) Perovskites: Vapor-Assisted Solution Deposition and Application as Solar Cell Absorbers.

    Science.gov (United States)

    Sedighi, Rahime; Tajabadi, Fariba; Shahbazi, Saeed; Gholipour, Somayeh; Taghavinia, Nima

    2016-08-01

    There have been recent reports on the formation of single-halide perovskites, CH3 NH3 PbX3 (X=Cl, Br, I), by means of vapor-assisted solution processing. Herein, the successful formation of mixed-halide perovskites (CH3 NH3 PbI3-x Xx ) by means of a vapor-assisted solution method at ambient atmosphere is reported. The perovskite films are synthesized by exposing PbI2 film to CH3 NH3 X (X=I, Br, or Cl) vapor. The prepared perovskite films have uniform surfaces with good coverage, as confirmed by SEM images. The inclusion of chlorine and bromine into the structure leads to a lower temperature and shorter reaction time for optimum perovskite film formation. In the case of CH3 NH3 PbI3-x Clx , the optimum reaction temperature is reduced to 100 °C, and the resulting phases are CH3 NH3 PbI3 (with trace Cl) and CH3 NH3 PbCl3 with a ratio of about 2:1. In the case of CH3 NH3 PbI3-x Brx , single-phase CH3 NH3 PbI2 Br is formed in a considerably shorter reaction time than that of CH3 NH3 PbI3 . The mesostructured perovskite solar cells based on CH3 NH3 PbI3 films show the best optimal power conversion efficiency of 13.5 %, whereas for CH3 NH3 PbI3-x Clx and CH3 NH3 PbI3-x Brx the best recorded efficiencies are 11.6 and 10.5 %, respectively.

  20. Microstructural development and control in YBa[sub 2]Cu[sub 3]O[sub y

    Energy Technology Data Exchange (ETDEWEB)

    Holesinger, T. G. (Terry G.); Gibbons, B. J. (Brady J.); Foltyn, S. R. (Stephen R.); Arendt, P. N. (Paul N.); Groves, J. R. (James R.); Coulter, J. Y. (James Y.)

    2001-01-01

    A study of some defect structures in Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} (Y-123)coated conductors based on ion-beam -assisted-deposition (IBAD) of yttria-stabilized zirconia (YSZ) on nickel alloy substrates is presented. Defect structures can originate anywhere in the coated conductor architecture. Defects can be additive and propagate through the entire film structure to affect the growth, orientation, arid properties of the superconducting film. Interfacial Ieactions between Y- 123 and the underlying buffer layer and the corresponding effects on the transport properticis of the films can be controlled with the thickness of the underlying buffer layer. With a 9Ow ceria buffer layer on an IBAD YSZ coated metal substrate, a J, value of 1.7 MA/cm{sup 2} (self-field, 75K) was obtained in a 1.5{micro}m thick Y-123 film.

  1. Fe Spin Reorientation across the Metamagnetic Transition in Strained FeRh Thin Films

    Science.gov (United States)

    Bordel, C.; Juraszek, J.; Cooke, David W.; Baldasseroni, C.; Mankovsky, S.; Minár, J.; Ebert, H.; Moyerman, S.; Fullerton, E. E.; Hellman, F.

    2012-09-01

    A spin reorientation accompanying the temperature-induced antiferromagnetic (AFM) to ferromagnetic (FM) phase transition is reported in strained epitaxial FeRh thin films. Fe57 conversion electron Mössbauer spectrometry showed that the Fe moments have different orientations in FeRh grown on thick single-crystalline MgO and in FeRh grown on ion-beam-assist-deposited (IBAD) MgO. It was also observed, in both samples, that the Fe moments switch orientations at the AFM to FM phase transition. Perpendicular anisotropy was evidenced in the AFM phase of the film grown on IBAD MgO and in the FM phase of that grown on regular MgO. Density-functional theory calculations enabled this spin-reorientation transition to be accurately reproduced for both FeRh films across the AFM-FM phase transition and show that these results are due to differences in strain.

  2. Microstructure and Electrical Properties of PMN-PT Thin Films Prepared by Oxygen Plasma Assisted Pulsed Laser Deposition%氧等离子体辅助脉冲激光沉积法制备PMN-PT薄膜的微观结构和电学性能

    Institute of Scientific and Technical Information of China (English)

    何邕; 李效民; 高相东; 冷雪; 王炜

    2011-01-01

    Lead magnesium niobate-lead titanate (PMN-PT) ferroelectric thin films with composition near the morphotropic phase boundary (MPB) were deposited on Si substrate by oxygen plasma assisted pulsed laser deposition (PLD).Highly (001)-oriented PMN-PT thin films with lower oxygen defect and higher crystalline property were obtained.The results show that the microstructure and electrical properties of PMN-PT thin films strongly depend on the partial pressure and the activity of oxygen in the deposition process.With the use of oxygen plasma,the dielectric constant of the PMN-PT thin film is increased from 1484 to 3012,the remnant polarization (2Pr) changes from 18μC/cm2 to 38 μC/cm2.%采用氧等离子体辅助脉冲激光沉积方法(PLD)在硅衬底上,制备出高度(001)取向的钙钛矿相结构钛铌镁酸铅(PMN-PT)薄膜.研究了氧等离子体辅助对PMN-PT薄膜相结构、微观形貌和电学性能的影响.结果表明,通过在薄膜沉积过程中引入高活性的氧等离子,可以有效地提高PMN-PT薄膜的结晶质量和微观结构.未采用氧等离子体辅助PLD方法制备PMN-PT薄膜的介电常数(10 kHz)和剩余极化(2Pr)分别为1484和18 μC/cm2,通过采用氧等离子体辅助,其介电常数和剩余极化分别提高至3012和38 μC/cm2.

  3. Biosensor Applications of MAPLE Deposited Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2014-10-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique derived from Pulsed Laser Deposition (PLD for deposition of delicate (polymers, complex biological molecules, etc. materials in undamaged form. The main difference of MAPLE technique with respect to PLD is the target: it is a frozen solution or suspension of the (guest molecules to be deposited in a volatile substance (matrix. Since laser beam energy is mainly absorbed by the matrix, damages to the delicate guest molecules are avoided, or at least reduced. Lipase, an enzyme catalyzing reactions borne by triglycerides, has been used in biosensors for detection of β-hydroxyacid esters and triglycerides in blood serum. Enzymes immobilization on a substrate is therefore required. In this paper we show that it is possible, using MAPLE technique, to deposit lipase on a substrate, as shown by AFM observation, preserving its conformational structure, as shown by FTIR analysis.

  4. Electron transfer with self-assembled copper ions at Au-deposited biomimetic films: mechanistic ‘anomalies’ disclosed by temperature- and pressure-assisted fast-scan voltammetry

    International Nuclear Information System (INIS)

    It has been suggested that electron transfer (ET) processes occurring in complex environments capable of glass transitions, specifically in biomolecules, under certain conditions may experience the medium’s nonlinear response and nonergodic kinetic patterns. The interiors of self-assembled organic films (SAMs) deposited on solid conducting platforms (electrodes) are known to undergo glassy dynamics as well, hence they may also exhibit the abovementioned ‘irregularities’. We took advantage of Cu2+ ions as redox-active probes trapped in the Au-deposited  −COOH-terminated SAMs, either L-cysteine, or 3-mercaptopropionic acid diluted by the inert 2-mercaptoethanol, to systematically study the impact of glassy dynamics on ET using the fast-scan voltammetry technique and its temperature and high-pressure extensions. We found that respective kinetic data can be rationalized within the extended Marcus theory, taking into account the frictionally controlled (adiabatic) mechanism for short-range ET, and complications due to the medium’s nonlinear response and broken ergodicity. This combination shows up in essential deviations from the conventional energy gap (overpotential) dependence and in essentially nonlinear temperature (Arrhenius) and high-pressure patterns, respectively. Biomimetic aspects for these systems are also discussed in the context of recently published results for interfacial ET involving self-assembled blue copper protein (azurin) placed in contact with a glassy environment. (paper)

  5. Physician-Assisted Death

    OpenAIRE

    Senn, John S.

    1994-01-01

    Physician-assisted death includes both euthanasia and assistance in suicide. The CMA urges its members to adhere to the principles of palliative care. It does not support euthanasia and assisted suicide. The following policy summary includes definitions of euthanasia and assisted suicide, background information, basic ethical principles and physician concerns about legalization of physician-assisted death.

  6. Deposit model for volcanogenic uranium deposits

    Science.gov (United States)

    Breit, George N.; Hall, Susan M.

    2011-01-01

    Volcanism is a major contributor to the formation of important uranium deposits both close to centers of eruption and more distal as a result of deposition of ash with leachable uranium. Hydrothermal fluids that are driven by magmatic heat proximal to some volcanic centers directly form some deposits. These fluids leach uranium from U-bearing silicic volcanic rocks and concentrate it at sites of deposition within veins, stockworks, breccias, volcaniclastic rocks, and lacustrine caldera sediments. The volcanogenic uranium deposit model presented here summarizes attributes of those deposits and follows the focus of the International Atomic Energy Agency caldera-hosted uranium deposit model. Although inferred by some to have a volcanic component to their origin, iron oxide-copper-gold deposits with economically recoverable uranium contents are not considered in this model.

  7. Laser-assisted growth of carbon nanotubes - A review

    NARCIS (Netherlands)

    Burgt, Y. van de

    2014-01-01

    Laser-assisted chemical vapor deposition (LACVD) is an attractive maskless process for growing locally carbon nanotubes at selected places on substrates that may contain temperature-sensitive components. This review gives a comprehensive overview of the reported research with respect to laser assist

  8. Optimization the condition of electrochemical deposition platinum nanocatalyst assisted with citric acid root%柠檬酸根辅助电沉积制备铂纳米粒子及其制备条件的优化

    Institute of Scientific and Technical Information of China (English)

    金碧瑶; 赵莲花

    2012-01-01

    An indium tin oxide(ITO) electrode is used as the substrate for supporting Pt particles prepared by potentiostatic method with citric acid root.By changing the applied potential,citric acid sodium concentration,precursor concentration and electrolyte concentration to optimize platinum nanoparticles preparation conditions.Using X-ray diffraction(XRD) to represent the crystal phase structure of Pt particle deposited on the ITO,using cycle volt ampere(CV) to determine the electric catalytic oxidation performance of Pt/ITO electrode in acid medium.The experimental results show that the preparation conditions of better electrocatalytic performance of the platinum nanoparticles is the applied potential of-0.3V,H2PtCl6 concentration is 0.8 mmol/L,citric acid sodium concentration is 20 mmol/L and electrolyte HClO4 concentration is 0.1 mol/L.%以氧化铟锡(ITO)透明导电玻璃为基体,在柠檬酸根存在下,采用恒电位电化学沉积法制备铂纳米粒子,并通过改变施加电位、柠檬酸钠浓度、前驱体浓度和电解质浓度来优化铂纳米粒子的制备条件.利用X射线衍射(XRD)表征在ITO表面沉积的Pt颗粒的晶相结构,并运用循环伏安法(CV)测定Pt/ITO电极在酸性介质中的电催化氧化性能.实验结果表明,在施加电位为-0.3V、H2PtCl6浓度为0.8mmol/L、柠檬酸钠浓度为20mmol/L和电解质HClO4浓度为0.1mol/L的条件下,制备出的铂纳米粒子的电催化性能较好.

  9. Microstructural and Tribological Characterization of Duplex Coatings with Additional Ion Bombardment

    Institute of Scientific and Technical Information of China (English)

    B.Skorie; D.Kakas; M.akita

    2004-01-01

    A duplex surface treatment involves the sequential application of two surface technologies to produce a surface composition with combined properties. A typical duplex process involves plasma nitriding and the PVD coating treatment of steels. In the paper are presented characteristics of hard coatings, type TiN, produced by classic technology PVD (physical vapour deposition) and IBAD (ion beam assisted deposition). Subsequent ion implantation was provided with N5+ ions. The dependence of friction coefficient was investigated by means of tribometer (pin-on-ring). The sliding pair was TiN thin coating on steel pin combined with steel ring without coating. The ring was produced from hardenable steel.

  10. Microstructural and Tribological Characterization of Duplex Coatings with Additional Ion Bombardment

    Institute of Scientific and Technical Information of China (English)

    B.(S)kori(c); D.Kaka(s); M.Rakita

    2004-01-01

    A duplex surface treatment involves the sequential application of two surface technologies to produce a surface composition with combined properties. A typical duplex process involves plasma nitriding and the PVD coating treatment of steels. In the paper are presented characteristics of hard coatings, type TiN, produced by classic technology PVD (physical vapour deposition) and IBAD (ion beam assisted deposition). Subsequent ion implantation was provided with N5+ions. The dependence of friction coefficient was investigated by means of tribometer (pin-on-ring). The sliding pair was TiN thin coating on steel pin combined with steel ring without coating. The ring was produced from hardenable steel.

  11. Fundamentals of laser-assisted fabrication of inorganic and organic films

    DEFF Research Database (Denmark)

    Schou, Jørgen

    2008-01-01

    The standard method for producing films by laser-assisted methods, Pulsed Laser Deposition (PLD) will be reviewed. The films considered are usually inorganic films, but also films of organic materials have been produced. Also the deposition of organic films by MAPLE (Matrix Assisted Pulsed Laser...

  12. Antireflection coatings on plastics deposited by plasma polymerization process

    Indian Academy of Sciences (India)

    K M K Srivatsa; M Bera; A Basu; T K Bhattacharya

    2008-08-01

    Antireflection coatings (ARCs) are deposited on the surfaces of optical elements like spectacle lenses to increase light transmission and improve their performance. In the ophthalmic industry, plastic lenses are rapidly displacing glass lenses due to several advantageous features. However, the deposition of ARCs on plastic lenses is a challenging task, because the plastic surface needs treatment for adhesion improvement and surface hardening before depositing the ARC. This surface treatment is usually done in a multi-stage process—exposure to energetic radiations, followed by deposition of a carbonyl hard coating by spin or dip coating processes, UV curing, etc. However, this treatment can also be done by plasma processes. Moreover, the plasma polymerization process allows deposition of optical films at room temperature, essential for plastics. The energetic ions in plasma processes provide similar effects as in ion assisted physical deposition processes to produce hard coatings, without requiring sophisticated ion sources. The plasma polymerization process is more economical than ion-assisted physical vapour deposition processes as regards equipment and source materials and is more cost-effective, enabling the surface treatment and deposition of the ARC in the same deposition system in a single run by varying the system parameters at each step. Since published results of the plasma polymerization processes developed abroad are rather sketchy and the techniques are mostly veiled in commercial secrecy, innovative and indigenous plasma-based techniques have been developed in this work for depositing the complete ARCs on plastic substrates.

  13. Structural characterization of MAPLE deposited lipase biofilm

    Science.gov (United States)

    Aronne, Antonio; Ausanio, Giovanni; Bloisi, Francesco; Calabria, Raffaela; Califano, Valeria; Fanelli, Esther; Massoli, Patrizio; Vicari, Luciano R. M.

    2014-11-01

    Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography-mass spectrometry gave results consistent with undamaged deposition of lipase.

  14. Diamond deposition on siliconized stainless steel

    International Nuclear Information System (INIS)

    Silicon diffusion layers in AISI 304 and AISI 316 type stainless steels were investigated as an alternative to surface barrier coatings for diamond film growth. Uniform 2 μm thick silicon rich interlayers were obtained by coating the surface of the steels with silicon and performing diffusion treatments at 800 deg. C. Adherent diamond films with low sp2 carbon content were deposited on the diffused silicon layers by a modified hot filament assisted chemical vapor deposition (HFCVD) method. Characterization of as-siliconized layers and diamond coatings was performed by energy dispersive X-ray analysis, scanning electron microscopy, X-ray diffraction and Raman spectroscopy.

  15. Atmospheric Deposition Modeling Results

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides data on model results for dry and total deposition of sulfur, nitrogen and base cation species. Components include deposition velocities, dry...

  16. Electro-Deposition Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The electro-deposition laboratory can electro-deposit various coatings onto small test samples and bench level prototypes. This facility provides the foundation for...

  17. Calcium Pyrophosphate Deposition (CPPD)

    Science.gov (United States)

    ... Patient / Caregiver Diseases & Conditions Calcium Pyrophosphate Deposition (CPPD) Calcium Pyrophosphate Deposition (CPPD) Fast Facts The risk of ... young people, too. Proper diagnosis depends on detecting calcium pyrophosphate crystals in the fluid of an affected ...

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

    Institute of Scientific and Technical Information of China (English)

    LI; Dejun

    2001-01-01

    [1]Gallagher, J. J., Simpson, J. A., Search for trapped electrons and a magnetic moment at Mars by Mariner IV, Science, 1965, 149: 1233—1239.[2]Russell, C. T., The magnetic field of Mars: Mars 3 evidence reexamined, Geophys. Res. Lett., 1978, 5: 81—86.[3]Riedler, W., Schwingenschun, K., Lichtenegger, H. et al., Interaction of solar wind with the planet Mars: Phobos 2 magnetic field observations, Planet. Space Sci., 1991, 39: 75—81.[4]Gringauz, K. I., What was known about the Martian magnetosphere before Phobos-2 mission, Planet. Space Sci., 1991, 39: 73—74.[5]Acuna, M. H., Connerney, J. E. P., Wasilewski, P. et al., Magnetic field and plasma observations at Mars: Initial results of the Mars global surveyor mission, Science, 1998, 279: 1676—1680.[6]Mohlmann, D., Riedler. W., Rustenbuch, J. et al., The question of an internal Martian magnetic field, Planet. Space Sci., 1991, 39: 83—88.[7]Shi, J. K., Liu, Z. X., Zhang, T. L., A theoretical study on the O+ ions of the Martian magnetosphere, Chin Astron Astrophys., 1999, 23: 377—383.[8]Rosenbauer, H., Shutte, N., Apathy, I. et al., Ions of Martian origin and plasma sheet in the Martian magnetotail: Initial results of TAUS experiment, Nature, 1989, 341: 612—614.[9]Lundin, R., Zakharov, A., Pelinen, R. et al., ASPERA/Phobos measurements of the ion outflow from the Martian ionosphere, Geophy. Res. Lett., 1990, 17: 873—876.[10]Verigin, M. I., Shutte, N. M., Galeev, A. A. et al., Ions of planetary origin in the Martian magnetosphere (Phobos 2 / TAUS experiment), Planet. Space Sci., 1991, 39: 131—137.[11]Lundin, R., Zakharov, A., Pelinen, R. et al., First measurements of the ionospheric plasma escape from Mars, Nature, 1989, 341: 609—612.[12]Lammer, H., Bauer, S. J., Nonthermal atmospheric escape from Mars and Titan, J. Geophys. Res., 1991, 96: 1819—1826.[13]Haider, S. A., O+ escape in the polar ion exosphere of Mars, Adv. Space Res., 1995, 16: 49—55.[14]Shi. J. K., Liu, Z. X., Zhang, T. L. et al., The influence of the intrinsic magnetic field on the distribution of O+ in Martian magnetosphere, Chinese Science Bulletin (in Chinese), 1997, 42(23): 1898—1901.[15]Luhmann, J. G., Brace, L. H., Near-Mars space, Rev. Geophys., 1991, 29: 121—140.[16]Luhmann, J. G., Schwingenschuh, K., A model of the magnetic ion environment of Mars, J. Geophys. Res., 1990, 95: 939—945.[17]Slavin, J. A., Schwingenschuh, K., Reidler, W. et al., The solar wind interaction with Mars: Mariner-4, Mars-2,3,5, and Phobos-2 observation of bow shock position and shape, J. Geophys. Res., 1991, 96: 11235—11241.[18]Eviater, A., Lencheek, A. M., Singer, S. F., Distribution of density in an ion-exosphere of a nonrotating planet, Phys. Fluids, 1964, 7: 1775—1779.

  19. ForeignAssistance.gov

    Data.gov (United States)

    US Agency for International Development — ForeignAssistance.gov provides a view of U.S. Government foreign assistance funds across agencies and enables users to explore, analyze, and review aid investments...

  20. Assisted Living Community Profile

    Science.gov (United States)

    ... for the Seniors Housing & Care Industry, reflects NCAL's philosophy of assisted living. 2 Data also from the ... Assisted Living Studies Clinical Practice Guidelines Health Information Technology In-Service Training Tools Periodicals State Regulatory Review ...

  1. Assisted Reproductive Technology (ART)

    Science.gov (United States)

    ... Information Clinical Trials Resources and Publications Assisted Reproductive Technology (ART) Skip sharing on social media links Share ... American Society for Reproductive Medicine. (2012). Assisted reproductive technologies: A guide for patients . Retrieved June 11, 2012, ...

  2. Acid Deposition Phenomena

    International Nuclear Information System (INIS)

    Acid deposition, commonly known as acid rain, occurs when emissions from the combustion of fossil fuels and other industrial processes undergo complex chemical reactions in the atmosphere and fall to the earth as wet deposition (rain, snow, cloud, fog) or dry deposition (dry particles, gas). Rain and snow are already naturally acidic, but are only considered problematic when less than a ph of 5.0 The main chemical precursors leading to acidic conditions are atmospheric concentrations of sulfur dioxide (SO2) and nitrogen oxides (NOx). When these two compounds react with water, oxygen, and sunlight in the atmosphere, the result is sulfuric (H2SO4) and nitric acids (HNO3), the primary agents of acid deposition which mainly produced from the combustion of fossil fuel and from petroleum refinery. Airborne chemicals can travel long distances from their sources and can therefore affect ecosystems over broad regional scales and in locations far from the sources of emissions. According to the concern of petroleum ministry with the environment and occupational health, in this paper we will discussed the acid deposition phenomena through the following: Types of acidic deposition and its components in the atmosphere Natural and man-made sources of compounds causing the acidic deposition. Chemical reactions causing the acidic deposition phenomenon in the atmosphere. Factors affecting level of acidic deposition in the atmosphere. Impact of acid deposition. Procedures for acidic deposition control in petroleum industry

  3. Structural and mechanical properties of nano-crystal TiN coatings

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chenhui; PAN Guoshun; LUO Jianbin; LI Wenzhi; CHEN Darong

    2004-01-01

    The structural and mechanical properties of TiN coatings prepared by ion beam assisted deposition (IBAD) were studied. The coatings have a polycrystal structure with grain size of ~10 nm or less. The hardness of the coatings increases with increasing grain size of TiN crystallites. The coating with grain size of 10.3 nm even has a superhardness of 44.7GPa. The relationship between the hardness and the grain size in the nano-crystalline coatings was discussed on the basis of grain-boundary triple junctions.

  4. Ion implantation inhibits cell attachment to glassy polymeric carbon

    International Nuclear Information System (INIS)

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

  5. {sup 14}N depth profiles in Ti and Ti6Al4V nitrided by various methods, measured by nuclear reaction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vickridge, I.; Trompetter, B. [Institute of Geological and Nuclear Sciences Ltd., Lower Hutt (New Zealand); Brown, I. [Industrial Research Ltd, Lower Hutt (New Zealand)

    1993-12-31

    Titanium alloys have desirable mechanical properties for applications in many areas, but their surface properties, such as friction coefficient, hardness, and wear and corrosion resistance often need to be enhanced. This may be accomplished by forming a thin layer of titanium nitride on the surface, by such methods as thermal nitriding, Ion Beam Assisted Deposition (IBAD), sol-gel technology, or ion implantation. Ion Beam Analysis is assuming an increasing importance for characterising the composition of the outer few microns since it is the only technique that can rapidly yield quantitative concentration depth profiles of {sup 14}N with minimal disruption of the analysed region. 8 refs., 7 figs.

  6. Airfoil deposition model

    Science.gov (United States)

    Kohl, F. J.

    1982-01-01

    The methodology to predict deposit evolution (deposition rate and subsequent flow of liquid deposits) as a function of fuel and air impurity content and relevant aerodynamic parameters for turbine airfoils is developed in this research. The spectrum of deposition conditions encountered in gas turbine operations includes the mechanisms of vapor deposition, small particle deposition with thermophoresis, and larger particle deposition with inertial effects. The focus is on using a simplified version of the comprehensive multicomponent vapor diffusion formalism to make deposition predictions for: (1) simple geometry collectors; and (2) gas turbine blade shapes, including both developing laminar and turbulent boundary layers. For the gas turbine blade the insights developed in previous programs are being combined with heat and mass transfer coefficient calculations using the STAN 5 boundary layer code to predict vapor deposition rates and corresponding liquid layer thicknesses on turbine blades. A computer program is being written which utilizes the local values of the calculated deposition rate and skin friction to calculate the increment in liquid condensate layer growth along a collector surface.

  7. 以光辅助MOCVD法在有取向Ni衬底及LAO单晶衬底上制备YBCO外延膜的比较研究%Comparative Study of YBCO Films Grown on Biaxially Textured Ni Substrate and LAO Substrate by Photo-assisted Metal Organic Chemical Vapor Deposition

    Institute of Scientific and Technical Information of China (English)

    李善文; 李伟; 李国兴; 张宝林; 周本初; 陶伯万; 高忠民

    2013-01-01

    采用光辅助金属有机物化学气相沉积(MOCVD)法,在生长有CeO2/YSZ/Y2 O3(YSZ为Y稳定的ZrO2)缓冲层的双轴取向Ni衬底上进行了YBa2 Cu3 O7_x(YBCO)外延膜生长,并与LaAlO3(100)[LAO(100)]单晶衬底上的YBCO外延膜生长进行了对比.发现在Ni衬底上c轴取向YBCO外延膜的生长温度比LAO衬底上的生长温度低约30℃,但生长速度更快.经分析认为,这种差别主要是由于Ni衬底的热导率比LAO衬底高造成的.Ni衬底及LAO衬底上生长的c轴取向YBCO外延膜的超导极限电流密度(Jc)分别约为0.5 MA/cm2及1.8 MA/cm2.%A comparative study of YBa2Cu307-χ( YBCO) films grown on biaxially textured Ni substrates [using CeO2/YSZ/Y2O3(YSZ is Y stabilized ZrO2) as buffer layers] and LaA103( 100) [LAO( 100) ] substrates by photo-assisted metal organic chemical vapor deposition ( MOCVD) was carried out. It is found that the growing temperature of YBCO film grown on Ni substrate is lower about 30℃ than that on LAO substrate. Besides, the growth rate on Ni substrate is higher than that on LAO. The phenomena can be explained by the fact that the thermal conduction of Ni substrate is better than LAO. The critical superconducting current density Jc of YBCO films grown on Ni substrate and LAO substrate are about 0. 5 and 1. 8 MA/cm2, respectively.

  8. Assistance Focus: Africa (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-12-01

    The Clean Energy Solutions Center Ask an Expert service connects governments seeking policy information and advice with one of more than 30 global policy experts who can provide reliable and unbiased quick-response advice and information. The service is available at no cost to government agency representatives from any country and the technical institutes assisting them. This publication presents summaries of assistance provided to African governments, including the benefits of that assistance.

  9. Microstructure of vapor deposited coatings on curved substrates

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G., E-mail: haydn@virginia.edu [Department of Materials Science and Engineering, University of Virginia, 395 McCormick Rd., P.O. Box 400745, Charlottesville, Virginia 22904 (United States)

    2015-09-15

    Thermal barrier coating systems consisting of a metallic bond coat and ceramic over layer are widely used to extend the life of gas turbine engine components. They are applied using either high-vacuum physical vapor deposition techniques in which vapor atoms rarely experience scattering collisions during propagation to a substrate, or by gas jet assisted (low-vacuum) vapor deposition techniques that utilize scattering from streamlines to enable non-line-of-sight deposition. Both approaches require substrate motion to coat a substrate of complex shape. Here, direct simulation Monte Carlo and kinetic Monte Carlo simulation methods are combined to simulate the deposition of a nickel coating over the concave and convex surfaces of a model airfoil, and the simulation results are compared with those from experimental depositions. The simulation method successfully predicted variations in coating thickness, columnar growth angle, and porosity during both stationary and substrate rotated deposition. It was then used to investigate a wide range of vapor deposition conditions spanning high-vacuum physical vapor deposition to low-vacuum gas jet assisted vapor deposition. The average coating thickness was found to increase initially with gas pressure reaching a maximum at a chamber pressure of 8–10 Pa, but the best coating thickness uniformity was achieved under high vacuum deposition conditions. However, high vacuum conditions increased the variation in the coatings pore volume fraction over the surface of the airfoil. The simulation approach was combined with an optimization algorithm and used to investigate novel deposition concepts to tailor the local coating thickness.

  10. Microstructure of vapor deposited coatings on curved substrates

    International Nuclear Information System (INIS)

    Thermal barrier coating systems consisting of a metallic bond coat and ceramic over layer are widely used to extend the life of gas turbine engine components. They are applied using either high-vacuum physical vapor deposition techniques in which vapor atoms rarely experience scattering collisions during propagation to a substrate, or by gas jet assisted (low-vacuum) vapor deposition techniques that utilize scattering from streamlines to enable non-line-of-sight deposition. Both approaches require substrate motion to coat a substrate of complex shape. Here, direct simulation Monte Carlo and kinetic Monte Carlo simulation methods are combined to simulate the deposition of a nickel coating over the concave and convex surfaces of a model airfoil, and the simulation results are compared with those from experimental depositions. The simulation method successfully predicted variations in coating thickness, columnar growth angle, and porosity during both stationary and substrate rotated deposition. It was then used to investigate a wide range of vapor deposition conditions spanning high-vacuum physical vapor deposition to low-vacuum gas jet assisted vapor deposition. The average coating thickness was found to increase initially with gas pressure reaching a maximum at a chamber pressure of 8–10 Pa, but the best coating thickness uniformity was achieved under high vacuum deposition conditions. However, high vacuum conditions increased the variation in the coatings pore volume fraction over the surface of the airfoil. The simulation approach was combined with an optimization algorithm and used to investigate novel deposition concepts to tailor the local coating thickness

  11. Deposition patterns with Turbuhaler.

    Science.gov (United States)

    Borgström, L

    1994-01-01

    The degree of lung deposition is an important factor in the evaluation of different inhalation flow driven dry powder inhalers. A number of studies using radioactive and non-radioactive methods have been performed with Turbuhaler to assess lung deposition under different conditions. Mean total lung deposition of terbutaline sulfate or budesonide via Turbuhaler in healthy volunteers ranged from 21-32% of the dose when a normal inhalation flow (60L/min) was used. At a low flow (30L/min) a mean 15% of the dose was deposited in the lungs, a similar value as for a well-performed inhalation via a pressurized metered dose inhaler. Regional deposition of inhaled drug can be expressed as the ratio between the amount of drug deposited in the more peripheral parts of the lung relative to the more central parts. In a comparative study, budesonide and terbutaline sulfate were given by inhalation via Turbuhaler to healthy volunteers. The ratio of peripheral to central deposition was 2.03 for terbutaline and 1.72 for budesonide. Thus, both the water-soluble terbutaline sulfate and the non-water soluble budesonide seemed to behave in the same way when inhaled via Turbuhaler. In conclusion, Turbuhaler delivers over 20% of a metered dose to the lungs when inhaled at a normal inhalation flow rate. The regional deposition pattern in the lungs was the same for terbutaline sulfate and budesonide, in spite of differences in water solubility. PMID:10147081

  12. Assisted suicide and euthanasia.

    Science.gov (United States)

    van der Heide, Agnes

    2013-01-01

    Several countries have adopted laws that regulate physician assistance in dying. Such assistance may consist of providing a patient with a prescription of lethal medication that is self-administered by the patient, which is usually referred to as (physician) assistance in suicide, or of administering lethal medication to a patient, which is referred to as euthanasia. The main aim of regulating physician assistance in dying is to bring these practices into the open and to provide physicians with legal certainty. A key condition in all jurisdictions that have regulated either assistance in suicide or euthanasia is that physicians are only allowed to engage in these acts upon the explicit and voluntary request of the patient. All systems that allow physician assistance in dying have also in some way included the notion that physician assistance in dying is only accepted when it is the only means to address severe suffering from an incurable medical condition. Arguments against the legal regulation of physician assistance in dying include principled arguments, such as the wrongness of hastening death, and arguments that emphasize the negative consequences of allowing physician assistance in dying, such as a devaluation of the lives of older people, or people with chronic disease or disabilities. Opinion polls show that some form of accepting and regulating euthanasia and physician assistance in suicide is increasingly supported by the general population in most western countries. Studies in countries where physician assistance in dying is regulated suggest that practices have remained rather stable in most jurisdictions and that physicians adhere to the legal criteria in the vast majority of cases.

  13. Biomimetic thin film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Rieke, P.R.; Graff, G.E.; Campbell, A.A.; Bunker, B.C.; Baskaran, S.; Song, L.; Tarasevich, B.J.; Fryxell, G.E.

    1995-09-01

    Biological mineral deposition for the formation of bone, mollusk shell and other hard tissues provides materials scientists with illustrative materials processing strategies. This presentation will review the key features of biomineralization and how these features can be of technical importance. We have adapted existing knowledge of biomineralization to develop a unique method of depositing inorganic thin films and coating. Our approach to thin film deposition is to modify substrate surfaces to imitate the proteins found in nature that are responsible for controlling mineral deposition. These biomimetic surfaces control the nucleation and growth of the mineral from a supersaturated aqueous solution. This has many processing advantages including simple processing equipment, environmentally benign reagents, uniform coating of highly complex shapes, and enhanced adherence of coating. Many different types of metal oxide, hydroxide, sulfide and phosphate materials with useful mechanical, optical, electronic and biomedical properties can be deposited.

  14. Self-assembling and self-limiting monolayer deposition

    Science.gov (United States)

    Foest, Rüdiger; Schmidt, Martin; Gargouri, Hassan

    2014-02-01

    Effects of spatial ordering of molecules on surfaces are commonly utilized to deposit ultra-thin films with a thickness of a few nm. In this review paper, several methods are discussed, that are distinguished from other thin film deposition processes by exactly these effects that lead to self-assembling and self-limiting layer growth and eventually to coatings with unique and fascinating properties and applications in micro-electronics, optics, chemistry, or biology. Traditional methods for the formation of self-assembled films of ordered organic molecules, such as the Langmuir-Blodgett technique along with thermal atomic layer deposition (ALD) of inorganic molecules are evaluated. The overview is complemented by more recent developments for the deposition of organic or hybrid films by molecular layer deposition. Particular attention is given to plasma assisted techniques, either as a preparative, supplementary step or as inherent part of the deposition as in plasma enhanced ALD or plasma assisted, repeated grafting deposition. The different methods are compared and their film formation mechanisms along with their advantages are presented from the perspective of a plasma scientist. The paper contains lists of established film compounds and a collection of the relevant literature is provided for further reading.

  15. Egress door opening assister

    Energy Technology Data Exchange (ETDEWEB)

    Allison, Thomas L.

    2015-10-06

    A door opening spring assistance apparatus is set forth that will automatically apply a door opening assistance force using a combination of rods and coil springs. The release of the rods by the coil springs reduces the force required to set the door in motion.

  16. Medical Assisting Program Guide.

    Science.gov (United States)

    Georgia Univ., Athens. Dept. of Vocational Education.

    This guide presents the standard curriculum for technical institutes in Georgia. The curriculum addresses the minimum competencies for a medical assisting program. The program guide is designed to relate primarily to the development of those skills needed by individuals in the medical assisting field, such as medical law and ethics, typing,…

  17. FEMA Hazard Mitigation Assistance Flood Mitigation Assistance (FMA) Data

    Data.gov (United States)

    Department of Homeland Security — This dataset contains closed and obligated projects funded under the following Hazard Mitigation Assistance (HMA) grant programs: Flood Mitigation Assistance (FMA)....

  18. Automatic Payroll Deposit System.

    Science.gov (United States)

    Davidson, D. B.

    1979-01-01

    The Automatic Payroll Deposit System in Yakima, Washington's Public School District No. 7, directly transmits each employee's salary amount for each pay period to a bank or other financial institution. (Author/MLF)

  19. Modeled Wet Nitrate Deposition

    Data.gov (United States)

    U.S. Environmental Protection Agency — Modeled data on nitrate wet deposition was obtained from Dr. Jeff Grimm at Penn State Univ. Nitrate wet depostion causes acidification and eutrophication of surface...

  20. Podiform chromite deposits

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Location and characteristics of 1,124 individual mineral deposits of this type, with grade and tonnage models for chromium as well as several related elements.

  1. Uranium deposit research, 1983

    International Nuclear Information System (INIS)

    Research on uranium deposits in Canada, conducted as a prerequisite for assessment of the Estimated Additional Resources of uranium, revealed that (a) the uranium-gold association in rudites of the Huronian Supergroup preferably occurs in the carbon layers; (b) chloritized ore at the Panel mine, Elliot Lake, Ontario, occurs locally in tectonically disturbed areas in the vicinity of diabase dykes; (c) mineralization in the Black Sturgeon Lake area, Ontario, formed from solutions in structural and lithological traps; (d) the Cigar Lake deposit, Saskatchewan, has two phases of mineralization: monomineralic and polymetallic; (e) mineralization of the JEB (Canoxy Ltd.) deposit is similar to that at McClean Lake; (f) the uranium-carbon assemblage was identified in the Claude deposit, Carswell Structure; and (g) the Otish Mountains area, Quebec, should be considered as a significant uranium-polymetallic metallogenic province

  2. Alluvial Deposits in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This coverage maps alluvial deposits throughout Iowa. This generally would include areas of alluvial soils associated with modern streams that are identified on...

  3. Speleothem (Cave Deposit) Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, and other aspects of climate derived from mineral deposits found in caves. Parameter keywords describe what was measured...

  4. Social and Human Service Assistants

    Science.gov (United States)

    ... Similar Occupations More Info Summary Social and human service assistants help clients to identify and obtain benefits and services. Quick ... and Human Service Assistants Do Social and human service assistants provide client services, including support for families, in a wide ...

  5. Robotic assisted laparoscopic colectomy.

    LENUS (Irish Health Repository)

    Pandalai, S

    2010-06-01

    Robotic surgery has evolved over the last decade to compensate for limitations in human dexterity. It avoids the need for a trained assistant while decreasing error rates such as perforations. The nature of the robotic assistance varies from voice activated camera control to more elaborate telerobotic systems such as the Zeus and the Da Vinci where the surgeon controls the robotic arms using a console. Herein, we report the first series of robotic assisted colectomies in Ireland using a voice activated camera control system.

  6. Pulsed laser deposition of liquid crystals

    OpenAIRE

    Gonzalo de los Reyes, José; Dyer, P. E.; Hird, M.

    1997-01-01

    Thin films of 4-cyano-4’-pentylbiphenyl ~5CB! liquid crystal have been fabricated by pulsed laser deposition. The suitability of different lasers ~ArF, KrF and CO2) has been investigated over a range of fluence using visible-UV and infrared absorption and optical microscopy to characterise the films. High performance liquid chromatography ~HPLC! and matrix assisted laser desorption ionization mass spectroscopy ~MALDI-MS! were used to assess the extent of decomposition of the films. The result...

  7. Gemstone deposits of Serbia

    Directory of Open Access Journals (Sweden)

    Miladinović Zoran

    2016-06-01

    Full Text Available Gemstone minerals in Serbia have never been regarded as an interesting and significant resource. Nevertheless, more than 150 deposits and occurrences have been recorded and some of them preliminarily explored in the last 50 years. The majority of deposits and occurrences are located within the Serbo-Macedonian metallogenic province and the most significant metallogenic units at the existing level of knowledge are the Fruska Gora ore district, Cer ore district, Sumadija metallogenic zone, Kopaonik metallogenic zone and Lece-Halkidiki metallogenic zone. The most important genetic type of deposits is hydrothermal, particularly in case of serpentinite/peridotite as host/parent rock. Placer deposits are also economically important. The dominant gemstones are silica minerals: chalcedony (Chrysoprase, carnelian, bluish chalcedony etc., jasper (picture, landscape, red etc., common opal (dendritic, green, milky white etc., silica masses (undivided, and quartz (rock crystal, amethyst etc.. Beside silica minerals significant gemstones in Serbia include also beryl (aquamarine, garnet (almandine and pyrope, tourmaline, fluorite, rhodochrosite, carbonate-silica breccia, carbonate-silica onyx, silicified wood, howlite, serpentinite, marble onyx, and kyanite. This paper aims to present an overview of Serbian gemstone deposits and occurrences and their position based on a simplified gemstone metallogenic map of Serbia, as well as genetic-industrial classification of gemstone deposits and gemstone varieties.

  8. Uranium deposits in Africa

    International Nuclear Information System (INIS)

    Africa is not only known for its spectacular diamond, gold, copper, chromium, platinum and phosphorus deposits but also for its uranium deposits. At least two uranium provinces can be distinguished - the southern, with the equatorial sub-province; and the south Saharan province. Uranium deposits are distributed either in cratons or in mobile belts, the first of sandstone and quartz-pebble conglomerate type, while those located in mobile belts are predominantly of vein and similar (disseminated) type. Uranium deposits occur within Precambrian rocks or in younger platform sediments, but close to the exposed Precambrian basement. The Proterozoic host rocks consist of sediments, metamorphics or granitoids. In contrast to Phanerozoic continental uranium-bearing sediments, those in the Precambrian are in marginal marine facies but they do contain organic material. The geology of Africa is briefly reviewed with the emphasis on those features which might control the distribution of uranium. The evolution of the African Platform is considered as a progressive reduction of its craton area which has been affected by three major Precambrian tectonic events. A short survey on the geology of known uranium deposits is made. However, some deposits and occurrences for which little published material is available are treated in more detail. (author)

  9. Processing of C60 thin films by Matrix-Assisted Pulsed Laser Evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    2011-01-01

    Thin films of fullerenes (C60) were deposited onto silicon using matrix-assisted pulsed laser evaporation (MAPLE). The deposition was carried out from a frozen homogeneous dilute solution of C60 in anisole (0.67 wt%), and over a broad range of laser fluences, from 0.15 J/cm2 up to 3.9 J/cm2. MAPL...

  10. Robot-Assisted Prostatectomy

    Medline Plus

    Full Text Available ... this da Vinci assisted laparoscopic radical prostatectomy. Our scrub, which is Alex Santander, our nurse anesthetist back ... Okay, Dr. Pinon, you’re going to come scrub in? Yes, I will, yes. Dr. Pinon is ...

  11. TADS and Technical Assistance.

    Science.gov (United States)

    Trohanis, Pascal L.

    1983-01-01

    Accomplishments of the Technical Assistance Development System (TADS) are cited, current challenges (including program development, and communication and coordination) are noted, and the mission mandated for TADS is outlined. (CL)

  12. Robot-Assisted Prostatectomy

    Medline Plus

    Full Text Available ... joysticks and his feet pressing on pedals to control these robotic instruments. There’s almost always an assistant ... Sure. To help divide the tissue and to control bleeding. Right now I’m going to clean ...

  13. Robot-Assisted Prostatectomy

    Medline Plus

    Full Text Available ... Robotic Surgery. My name is Dr. Andy Pinon. This is my partner, Dr. Darren Bruck. He’s going ... at the very beginning, helping us navigate through this da Vinci assisted laparoscopic radical prostatectomy. Our scrub, ...

  14. Homelessness Assistance and Resources

    Science.gov (United States)

    ... Performance Measure Resources View videos, programming specifications, an introductory guide, and more on how CoCs can measure ... a Program Affordable Housing Community Development Consolidated Planning Economic Development Environmental Review Financial Management Homelessness Assistance Rural ...

  15. [Assisted peritoneal dialysis].

    Science.gov (United States)

    Klarić, Dragan; Prkačin, Ingrid

    2014-04-01

    According to the National Registry of Renal Replacement Therapy (RRT), the incidence of chronic kidney disease (end-stage renal disease) and the need of RRT have declined in the last decade renal. One of the reasons for this tendency certainly is transplantation as the best choice. However, transplant procedure has limitations in elderly patients due to the number of comorbidities. This study was designed as retrospective analysis of outcomes in patients treated with peritoneal dialysis for a period of eleven years. Patients were divided into those who had been assisted or unassisted. Out of 100 patients treated with peritoneal dialysis (PD), 77 completed the treatment, including 26 assisted and 51 unassisted patients. Peritonitis was recorded in 20 assisted and 26 unassisted patients. Peritonitis was more common in unassisted patients, who were more frequently lost from PD. Assisted PD could be a good and safe choice of RRT in this special group of patients.

  16. Superfund Technical Assistance Grants

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset includes data related to the Superfund Technical Assistance Grant program, including grant number, award amounts, award dates, period of performance,...

  17. Financial Assistance Information

    Science.gov (United States)

    ... Other Sites: Genetic and Rare Diseases Information Center Financial Assistance Information The National Institutes of Health (NIH) ... area call 900-638-0742. Top of page Financial Aid for Medical Treatments Information on financial aid ...

  18. Robot-Assisted Prostatectomy

    Medline Plus

    Full Text Available Watch South Miami Hospital Surgeons Perform Robot-Assisted Prostatectomy South Miami Hospital Miami, FL January 19, 2010 Good afternoon. Welcome to the South Miami Hospital operating room, the Center ...

  19. Computer assisted radiology

    International Nuclear Information System (INIS)

    The proceedings of the CAR'93 symposium present the 126 oral papers and the 58 posters contributed to the four Technical Sessions entitled: (1) Image Management, (2) Medical Workstations, (3) Digital Image Generation - DIG, and (4) Application Systems - AS. Topics discussed in Session (1) are: picture archiving and communication systems, teleradiology, hospital information systems and radiological information systems, technology assessment and implications, standards, and data bases. Session (2) deals with computer vision, computer graphics, design and application, man computer interaction. Session (3) goes into the details of the diagnostic examination methods such as digital radiography, MRI, CT, nuclear medicine, ultrasound, digital angiography, and multimodality imaging. Session (4) is devoted to computer-assisted techniques, as there are: computer assisted radiological diagnosis, knowledge based systems, computer assisted radiation therapy and computer assisted surgical planning. (UWA). 266 figs

  20. Accessibility and assistive products

    Science.gov (United States)

    Rodríguez-Porrero, Cristina

    2009-01-01

    Introduction Accessibility and assistive products and technologies are needed to ensure the rights of persons with disabilities and older persons. Many developments have been implemented in laws, standards, markets and from the consumers perspective, at international, European and national levels. The real issue is that not all the potential users benefit from the use of assistive products or accessible measures. Discussion Innovative methods are needed to allow all potential users to have real advantage of assistive technologies and accessible and design for all facilities. Best practices will be presented and existing gaps and recommendations will be discussed. Cost-benefits aspects will also be presented. Conclusion In order to get advantages from opportunities of globalization, hard work and responsibilities of all stakeholders are needed, so that assistive products and accessibility reach a whole range of situations and environments and contribute to ensure quality of life in a society for all.

  1. Heteronuclear proton assisted recoupling

    OpenAIRE

    De Paëpe, Gaël; Lewandowski, Józef R.; Loquet, Antoine; Eddy, Matt; Megy, Simon; Böckmann, Anja; Griffin, Robert G.

    2011-01-01

    We describe a theoretical framework for understanding the heteronuclear version of the third spin assisted recoupling polarization transfer mechanism and demonstrate its potential for detecting long-distance intramolecular and intermolecular 15N–13C contacts in biomolecular systems. The pulse sequence, proton assisted insensitive nuclei cross polarization (PAIN-CP) relies on a cross term between 1H–15N and 1H–13C dipolar couplings to mediate zero- and/or double-quantum 15N–13C recoupling. In ...

  2. CANDU energy for steam assisted gravity drainage

    International Nuclear Information System (INIS)

    Traditional open-pit mining has been used by industry for many years to remove oil sands from shallow deposits. To increase production capacity, the industry is looking for new technology to exploit bitumen from deep deposits. Among them, SAGD (Steam-Assisted Gravity Drainage) appears to be the most promising approach. It uses steam to remove bitumen from underground reservoirs. Recently, the SAGD recovery process has been put into commercial operation by major oil companies.Atomic Energy Canada Limited has assessed the use of the ACR-1000 as a source of heat and electricity for oil sand extraction and processing. The ACR-1000 design is an evolutionary development of the familiar CANDU technology, adding innovations to enhance economics, operations, and safety margins. The net electrical output from a standard ACR-1000 will be close to 1100 MWe, depending on local cooling water temperature

  3. Multiphoton polymerization using optical trap assisted nanopatterning

    Science.gov (United States)

    Leitz, Karl-Heinz; Tsai, Yu-Cheng; Flad, Florian; Schäffer, Eike; Quentin, Ulf; Alexeev, Ilya; Fardel, Romain; Arnold, Craig B.; Schmidt, Michael

    2013-06-01

    In this letter, we show the combination of multiphoton polymerization and optical trap assisted nanopatterning (OTAN) for the additive manufacturing of structures with nanometer resolution. User-defined patterns of polymer nanostructures are deposited on a glass substrate by a 3.5 μm polystyrene sphere focusing IR femtosecond laser pulses, showing minimum feature sizes of λ/10. Feature size depends on the applied laser fluence and the bead surface spacing. A finite element model describes the intensity enhancement in the microbead focus. The results presented suggest that OTAN in combination with multiphoton processing is a viable technique for additive nanomanufacturing with sub-diffraction-limited resolution.

  4. Aerosol-assisted fabrication of tin-doped indium oxide ceramic thin films from nanoparticle suspensions

    OpenAIRE

    Nirmal Peiris, T. A.; Ghanizadeh, S.; Jayathilake, D. S. Y.; Hutt, D.A.; Wijayantha, K. G. U.; Conway, P. P.; Southee, D. J.; Parkin, I. P.; Marchand, P.; Darr, J. A.; Carmalt, C. J.

    2016-01-01

    Sn-doped In2O3 (ITO) thin films were fabricated on float glass substrates from a nanoparticle suspension using a new and inexpensive aerosol-assisted chemical transport (AACT) process. The influence of the solvent type, loading level and film deposition time on the structural, electrical and optical properties of the deposited thin films was investigated. In addition, the effect of the post-deposition heat-treatment of ITO films on the film resistivity and transparency was investigated using ...

  5. Pulsed laser deposition: Prospects for commercial deposition of epitaxial films

    Energy Technology Data Exchange (ETDEWEB)

    Muenchausen, R.E.

    1999-03-01

    Pulsed laser deposition (PLD) is a physical vapor deposition (PVD) technique for the deposition of thin films. The vapor source is induced by the flash evaporation that occurs when a laser pulse of sufficient intensity (about 100 MW/cm{sup 2}) is absorbed by a target. In this paper the author briefly defines pulsed laser deposition, current applications, research directed at gaining a better understanding of the pulsed laser deposition process, and suggests some future directions to enable commercial applications.

  6. Evaluation of an IBAD thin-film process as an alternative method for surface incorporation of bioceramics on dental implants: a study in dogs Avaliação de um recobrimento de baixa espessura processado pela deposição assistida por feixe iônico como alternativa para a incorporação de biocerâmicas em implantes dentários: estudo em cães

    Directory of Open Access Journals (Sweden)

    Paulo G. Coelho

    2005-03-01

    Full Text Available Thin-film bioceramic coatings are potential alternatives to overcome the limitations provided by other commercially available coating techniques like PSHA, where variable bioceramic dissolution added to a metalloceramic weak link are process- inherent. The purpose of this investigation was to determine the overall and site specific (to 0.5 mm from implant surface levels of osseoactivity around a thin-film (IBAD processed coated titanium alloy implant versus a non surface modified (sand-blasted/acid etched titanium alloy implant in a canine model. The surgical model comprised the proximal tibiae epiphyses with four implants placed in each limb remaining for 2 and 4 weeks in-vivo. 10 mg/Kg oxytetracycline was administered 48 hours prior to euthanization. The limbs were retrieved by sharp dissection, reduced to blocks, and subsequently nondecalcified processed for fluorescent microscopy. Micrographs (20x mag were acquired around the implant perimeter and merged for overall biological response evaluations, and four micrographs (40x mag. subdivided in rectangles were acquired along one of the implant sides for tetracycline labeled area fraction quantification. The results showed biocompatible and osseoconductive properties for the thin-film coated and uncoated titanium alloy implants. Tetracycline labeled area fraction analyses showed that the thin-film coated implants presented significantly higher overall and site specific osseoactivity levels at 2 and 4 weeks. The site specific osseoactivity values were significantly higher compared to overall values for control and thin-film coated implants at both times in-vivo. According to the results obtained in this study, thin-film coated implants enhanced biological response at the early implantation times evaluated.Recobrimentos biocerâmicos de baixa espessura são potenciais alternativas para compensar as limitações de outros recobrimentos biocerâmicos disponíveis comercialmente como o plasma spray

  7. Vein type uranium deposits

    International Nuclear Information System (INIS)

    Veins are tabular- or sheet-like masses of minerals occupying or following a fracture or a set of fractures in the enclosing rock. They have been formed later than the country rock and fractures, either by filling of the open spaces or by partial or complete replacement of the adjoining rock or most commonly by both of these processes combined. This volume begins with the occurrences and deposits known from old shield areas and the sedimentary belts surrounding them. They are followed by papers describing the European deposits mostly of Variscan age, and by similar deposits known from China being of Jurassic age. The volume is completed by two papers which do not fit exactly in the given scheme. A separate abstract was prepared for each of the 25 papers in this report

  8. Shedding of ash deposits

    DEFF Research Database (Denmark)

    Zbogar, Ana; Frandsen, Flemming; Jensen, Peter Arendt;

    2009-01-01

    Ash deposits formed during fuel thermal conversion and located on furnace walls and on convective pass tubes, may seriously inhibit the transfer of heat to the working fluid and hence reduce the overall process efficiency. Combustion of biomass causes formation of large quantities of troublesome....... Low melting temperatures make straw ashes especially troublesome, since their stickiness is higher at lower temperatures, compared to coal ashes. Increased stickiness will eventually lead to a higher collection efficiency of incoming ash particles, meaning that the deposit may grow even faster...

  9. Computer Assisted Surgery

    Science.gov (United States)

    Arámbula Cosío, F.; Padilla Castañeda, M. A.

    2003-09-01

    Computer assisted surgery (CAS) systems can provide different levels of assistance to a surgeon during training and execution of a surgical procedure. This is done through the integration of : measurements taken on medical images; computer graphics techniques; and positioning or tracking mechanisms which accurately locate the surgical instruments inside the operating site. According to the type of assistance that is provided to the surgeon, CAS systems can be classified as: Image guided surgery systems; Assistant robots for surgery; and Training simulators for surgery. In this work are presented the main characteristics of CAS systems. It is also described the development of a computer simulator for training on Transurethral Resection of the Prostate (TURP) based on a computer model of the prostate gland which is able to simulate, in real time, deformations and resections of tissue. The model is constructed as a 3D mesh with physical properties such as elasticity. We describe the main characteristics of the prostate model and its performance. The prostate model will also be used in the development of a CAS system designed to assist the surgeon during a real TURP procedure. The system will provide 3D views of the shape of the prostate of the patient, and the position of the surgical instrument during the operation. The development of new computer graphics models which are able to simulate, in real time, the mechanical behavior of an organ during a surgical procedure, can improve significantly the training and execution of other minimally invasive surgical procedures such as laparoscopic gall bladder surgery.

  10. Improvement of orthodontic friction by coating archwire with carbon nitride film

    International Nuclear Information System (INIS)

    In order to reduce frictional resistance between archwire and bracket during orthodontic tooth movement, carbon nitride (CNx) thin films were deposited on the surface of archwires with ion beam assisted deposition (IBAD). The energy-dispersive X-ray spectrometer (EDS) analysis showed that the CNx film was successfully deposited on the surface of the orthodontic wires. X-ray photoelectron spectroscopy (XPS) analysis suggested that the deposited CNx film was sp2 carbon dominated structures, and diversiform bonds (N-C, N≡C, et al.) coexisted in the film. The friction tests indicated that the CNx film significantly reduced the wire-bracket friction both in ambient air and in artificial saliva. The sp2C rich structure of the CNx film as well as its protection function for the archwire was responsible for the low friction of the wire-bracket sliding system.

  11. Characterization of duplex hard coatings with additional ion implantation

    Directory of Open Access Journals (Sweden)

    B. Škorić

    2012-01-01

    Full Text Available In this paper, we present the results of a study of TiN thin fi lms which are deposited by a Physical Vapour Deposition (PVD and Ion Beam Assisted Deposition (IBAD. In the present investigation the subsequent ion implantation was provided with N+2 ions. The ion implantation was applied to enhance the mechanical properties of surface. The thin film deposition process exerts a number of eff ects such as crystallographic orientation, morphology, topography, densifi cation of the fi lms. The evolution of the microstructure from porous and columnar grains to densel packed grains is accompanied by changes in mechanical and physical properties. A variety of analytic techniques were used for characterization, such as scratch test, calo test, Scanning electron microscopy (SEM, Atomic Force Microscope (AFM, X-ray diff raction (XRD and Energy Dispersive X-ray analysis (EDAX.

  12. Improvement of orthodontic friction by coating archwire with carbon nitride film

    Energy Technology Data Exchange (ETDEWEB)

    Wei Songbo [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Shao Tianmin, E-mail: shaotm@mail.tsinghua.edu.cn [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Ding Peng [Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing 100081 (China)

    2011-10-01

    In order to reduce frictional resistance between archwire and bracket during orthodontic tooth movement, carbon nitride (CNx) thin films were deposited on the surface of archwires with ion beam assisted deposition (IBAD). The energy-dispersive X-ray spectrometer (EDS) analysis showed that the CNx film was successfully deposited on the surface of the orthodontic wires. X-ray photoelectron spectroscopy (XPS) analysis suggested that the deposited CNx film was sp{sup 2} carbon dominated structures, and diversiform bonds (N-C, N{identical_to}C, et al.) coexisted in the film. The friction tests indicated that the CNx film significantly reduced the wire-bracket friction both in ambient air and in artificial saliva. The sp{sup 2}C rich structure of the CNx film as well as its protection function for the archwire was responsible for the low friction of the wire-bracket sliding system.

  13. Mobile Autonomous Humanoid Assistant

    Science.gov (United States)

    Diftler, M. A.; Ambrose, R. O.; Tyree, K. S.; Goza, S. M.; Huber, E. L.

    2004-01-01

    A mobile autonomous humanoid robot is assisting human co-workers at the Johnson Space Center with tool handling tasks. This robot combines the upper body of the National Aeronautics and Space Administration (NASA)/Defense Advanced Research Projects Agency (DARPA) Robonaut system with a Segway(TradeMark) Robotic Mobility Platform yielding a dexterous, maneuverable humanoid perfect for aiding human co-workers in a range of environments. This system uses stereo vision to locate human team mates and tools and a navigation system that uses laser range and vision data to follow humans while avoiding obstacles. Tactile sensors provide information to grasping algorithms for efficient tool exchanges. The autonomous architecture utilizes these pre-programmed skills to form human assistant behaviors. The initial behavior demonstrates a robust capability to assist a human by acquiring a tool from a remotely located individual and then following the human in a cluttered environment with the tool for future use.

  14. "Total Deposition (TDEP) Maps"

    Science.gov (United States)

    The presentation provides an update on the use of a hybrid methodology that relies on measured values from national monitoring networks and modeled values from CMAQ to produce of maps of total deposition for use in critical loads and other ecological assessments. Additionally, c...

  15. Ethics and assisted reproduction.

    Science.gov (United States)

    Fasouliotis, S J; Schenker, J G

    2000-06-01

    In vitro fertilization and assisted reproductive technology have made great progress during the last 20 years. Genetic material donation, human embryo cryopreservation, selective embryo reduction, preimplantation genetic diagnosis and surrogacy are currently practiced in many countries. On the other hand, embryo research is practiced only in a small number of nations, whereas human cloning has thus far been universally condemned. The rapid evolution and progress of all these techniques of assisted reproduction has revealed certain ethical issues that have to be addressed. PMID:10825637

  16. Assisted Cycling Tours

    Science.gov (United States)

    Hollingsworth, Jan Carter

    2008-01-01

    This article discusses Assisted Cycling Tours (ACT), a Westminster, Colorado based 501(c)3, non-profit that is offering the joy of bicycle tours in breathtaking, scenic locations to children and adults with developmental and physical disabilities and their families. ACT was founded by Bob Matter and his son David with a goal of opening up the…

  17. Parent-Assisted Learning.

    Science.gov (United States)

    Niedermeyer, Fred C.

    The effects of parent-monitored practice at home on pupil performance in reading were investigated. The study used as instructional vehicles the Parent-Assisted Learning Program (PAL) and the Southwest Regional Laboratory's (SWRL) First-Year Communication Skills Program. PAL was designed to enable school personnel to establish a system whereby…

  18. Computer-assisted instruction

    NARCIS (Netherlands)

    J. Voogt; P. Fisser

    2015-01-01

    Since the early days of computer technology in education in the 1960s, it was claimed that computers can assist instructional practice and hence improve student learning. Since then computer technology has developed, and its potential for education has increased. In this article, we first discuss th

  19. Robot-Assisted Prostatectomy

    Medline Plus

    Full Text Available ... actually mimicking -- these mimicking the movement of the human hand and the human wrist. Clips, please. So what Dr. Pinon has ... for robots to operate without the assistance of humans? Not yet. We are not quite there. The ...

  20. Physician-Assisted Suicide

    Science.gov (United States)

    Module fourteen of the EPEC-O Self-Study Original Version focuses on the skills that the physician can use to respond both compassionately and confidently to a request, not on the merits of arguments for or against legalizing physician-assisted suicide (PAS) or euthanasia.

  1. Robotic assisted andrological surgery

    Institute of Scientific and Technical Information of China (English)

    Sijo J Parekattil; Ahmet Gudeloglu

    2013-01-01

    The introduction of the operative microscope for andrological surgery in the 1970s provided enhanced magnification and accuracy,unparalleled to any previous visual loop or magnification techniques.This technology revolutionized techniques for microsurgery in andrology.Today,we may be on the verge of a second such revolution by the incorporation of robotic assisted platforms for microsurgery in andrology.Robotic assisted microsurgery is being utilized to a greater degree in andrology and a number of other microsurgical fields,such as ophthalmology,hand surgery,plastics and reconstructive surgery.The potential advantages of robotic assisted platforms include elimination of tremor,improved stability,surgeon ergonomics,scalability of motion,multi-input visual interphases with up to three simultaneous visual views,enhanced magnification,and the ability to manipulate three surgical instruments and cameras simultaneously.This review paper begins with the historical development of robotic microsurgery.It then provides an in-depth presentation of the technique and outcomes of common robotic microsurgical andrological procedures,such as vasectomy reversal,subinguinal varicocelectomy,targeted spermatic cord denervation (for chronic orchialgia) and robotic assisted microsurgical testicular sperm extraction (microTESE).

  2. A deposit model for Mississippi Valley-Type lead-zinc ores: Chapter A in Mineral deposit models for resource assessment

    Science.gov (United States)

    Leach, David L.; Taylor, Ryan D.; Fey, David L.; Diehl, Sharon F.; Saltus, Richard W.

    2010-01-01

    This report is a descriptive model of Mississippi Valley-Type (MVT) lead-zinc deposits that presents their geological, mineralogical and geochemical attributes and is part of an effort by the U.S. Geological Survey Mineral Resources Program to update existing models and develop new models that will be used for an upcoming national mineral resource assessment. This deposit modeling effort by the USGS is intended to supplement previously published models for use in mineral-resource and mineral-environmental assessments. Included in this report are geological, geophysical and geochemical assessment guides to assist in mineral resource estimation. The deposit attributes, including grade and tonnage of the deposits described in this report are based on a new mineral deposits data set of all known MVT deposits in the world.

  3. The study and the realization of radiation detectors made from polycrystalline diamond films grown by microwave plasma enhanced chemical vapour deposition technique; Etude et realisation de detecteurs de rayonnements a base de films de diamant polycristallin elabores par depot chimique en phase vapeur assiste par plasma micro-onde

    Energy Technology Data Exchange (ETDEWEB)

    Jany, Ch

    1998-10-29

    The aim of this work was to develop radiation detectors made from polycrystalline diamond films grown by microwave plasma enhanced chemical vapour deposition technique. The influence of surface treatments, contact technology and diamond growth parameters on the diamond detectors characteristics was investigated in order to optimise the detector response to alpha particles. The first part of the study focused on the electrical behaviour of as-deposited diamond surface, showing a p type conduction and its influence on the leakage current of the device. A surface preparation process was established in order to reduce the leakage current of the device by surface dehydrogenation using an oxidising step. Several methods to form and treat electrical contacts were also investigated showing that the collection efficiency of the device decreases after contact annealing. In the second part, we reported the influence of the diamond deposition parameters on the characteristics of the detectors. The increase of the deposition temperature and/or methane concentration was shown to lead {eta} to decrease. In contrast, {eta} was found to increase with the micro-wave power. The evolution of the diamond detector characteristics results from the variation in sp{sup 2} phases incorporation and in the crystallography quality of the films. These defects increase the leakage current and reduce the carrier mobility and lifetime. Measurements carried out on detectors with different thicknesses showed that the physical properties varies along the growth direction, improving with the film thickness. Finally, the addition of nitrogen (> 10 ppm) in the gas mixture during diamond deposition was found to strongly reduce the collection efficiency of the detectors. To conclude the study, we fabricated and characterised diamond devices which were used for thermal neutron detection and for the intensity and shape measurement of VUV and soft X-ray pulses. (author)

  4. Navigating "Assisted Dying".

    Science.gov (United States)

    Schipper, Harvey

    2016-02-01

    Carter is a bellwether decision, an adjudication on a narrow point of law whose implications are vast across society, and whose impact may not be realized for years. Coupled with Quebec's Act Respecting End-of-life Care it has sharply changed the legal landscape with respect to actively ending a person's life. "Medically assisted dying" will be permitted under circumstances, and through processes, which have yet to be operationally defined. This decision carries with it moral assumptions, which mean that it will be difficult to reach a unifying consensus. For some, the decision and Act reflect a modern acknowledgement of individual autonomy. For others, allowing such acts is morally unspeakable. Having opened the Pandora's Box, the question becomes one of navigating a tolerable societal path. I believe it is possible to achieve a workable solution based on the core principle that "medically assisted dying" should be a very rarely employed last option, subject to transparent ongoing review, specifically as to why it was deemed necessary. My analysis is based on 1. The societal conditions in which have fostered demand for "assisted dying", 2. Actions in other jurisdictions, 3. Carter and Quebec Bill 52, 4. Political considerations, 5. Current medical practice. Leading to a series of recommendations regarding. 1. Legislation and regulation, 2. The role of professional regulatory agencies, 3. Medical professions education and practice, 4. Public education, 5. Health care delivery and palliative care. Given the burden of public opinion, and the legal steps already taken, a process for assisted-dying is required. However, those legal and regulatory steps should only be considered a necessary and defensive first step in a two stage process. The larger goal, the second step, is to drive the improvement of care, and thus minimize assisted-dying. PMID:27169205

  5. UV optical properties of thin film oxide layers deposited by different processes.

    Science.gov (United States)

    Pellicori, Samuel F; Martinez, Carol L

    2011-10-01

    UV optical properties of thin film layers of compound and mixed oxide materials deposited by different processes are presented. Japan Electron Optics Laboratory plasma ion assisted deposition (JEOL PIAD), electron beam with and without IAD, and pulsed DC magnetron sputtering were used. Comparisons are made with published deposition process data. Refractive indices and absorption values to as short as 145 nm were measured by spectroscopic ellipsometry (SE). Electronic interband defect states are detected that are deposition-process dependent. SE might be effective in identifying UV optical film quality, especially in defining processes and material composition beneficial for high-energy excimer laser applications and environments requiring stable optical properties.

  6. DAR Assisted Layer-by-Layer Assembly of Aromatic Compounds

    Institute of Scientific and Technical Information of China (English)

    姜思光; 陈晓东; 张莉; 刘鸣华

    2003-01-01

    A facile DAR (diphenylamine-4-diazonium-formaldehyde resin)assisted layer-by-layer (LbL) assembly of uitrathin organic film of aromatic compounds has been investigated. The muitilayer of pyrene or anthracene was fabricated through simple dipping of the glass slide into the mixed solution of DAR with the target compounds. In this method, DAR acted as an assistant compound to help the assembling of the aromatic compounds. Such a convenient deposition method not only reserves the advantages of the traditional LbL technique but also simplifies the technique and extends the effectiveness of LbL technique to small molecules without any charge.

  7. Thorium ore deposits

    International Nuclear Information System (INIS)

    The main occurences of the thorium minerals of the Argentine Republic which have not been exploited, due to their reduced volume, are described. The thoriferous deposits have three genetic types: pegmatitic, hydrothermal and detritic, being the most common minerals: monazite, thorite and thorogummite. The most important thorium accumulations are located in Salta, being of less importance those of Cordoba, Jujuy and San Juan. (M.E.L.)

  8. SuperAssist: Personal assistants for cooperative healthcare treatment

    NARCIS (Netherlands)

    Haan, G. de; Mast, C.A.P.G. van der; Blanson Henkemans, O.; Neerincx, M.A.

    2005-01-01

    Human-computer interaction, tele-medicine, supervision, personalization, ambient intelligence, health care, personal assistants, cooperative problem-solving. ABSTRACT This paper describes the research plans in the SuperAssist project, introducing personal assistants in the care of diabetes patients,

  9. DLC Films Deposited by the DC PACVD Method

    Directory of Open Access Journals (Sweden)

    D. Palamarchuk

    2003-01-01

    Full Text Available DLC (Diamond-Like Carbon coatings have been suggested as protective surface layers against wear. However hard DLC coatings, especially those of greater thickness, have poor adhesion to substrates. We have used several ways to increase the adhesion of DLC coatings prepared by the PACVD (Plasma Assisted Chemical Vapour Deposition method on steel substrates. One of these is the DC PACVD method for preparing DLC films.

  10. DLC Films Deposited by the DC PACVD Method

    OpenAIRE

    D. Palamarchuk; M. Zoriy; J. Gurovič; F. Černý; S. Konvičková; I. Hüttel

    2003-01-01

    DLC (Diamond-Like Carbon) coatings have been suggested as protective surface layers against wear. However hard DLC coatings, especially those of greater thickness, have poor adhesion to substrates. We have used several ways to increase the adhesion of DLC coatings prepared by the PACVD (Plasma Assisted Chemical Vapour Deposition) method on steel substrates. One of these is the DC PACVD method for preparing DLC films.

  11. Preparing for Assisted Reproductive Technology

    Science.gov (United States)

    ... CDC Cancel Submit Search The CDC Assisted Reproductive Technology (ART) Note: Javascript is disabled or is not ... visit this page: About CDC.gov . Assisted Reproductive Technology (ART) What Is ART Patient Resources Preparing for ...

  12. Rehabilitative and Assistive Technology: Overview

    Science.gov (United States)

    ... Clinical Trials Resources and Publications Rehabilitative and Assistive Technology: Overview Skip sharing on social media links Share this: Page Content Rehabilitative and assistive technology refers to tools, equipment, or products that can ...

  13. The classification of minerals deposits

    International Nuclear Information System (INIS)

    In this part of book author present the classification of minerals deposits. Deposit formation take place as a result of complicated and long geology processes in the wide temperature intervals (from 1500 digC to usual) and pressures (from usual and to tens kilobars). Deposits of minerals as other investigation objects require in definite systematization on the base of definite characteristics

  14. Laser assisted electron dynamics

    CERN Document Server

    Bray, Alexander William

    2016-01-01

    We apply the convergent close-coupling (CCC) formalism to analyse the processes of laser assisted electron impact ionisation of He, and the attosecond time delay in the photodetachment of the H^{-} ion and the photoionisation of He. Such time dependent atomic collision processes are of considerable interest as experimental measurements on the relevant timescale (attoseconds 10^{-18} s) are now possible utilising ultrafast and intense laser pulses. These processes in particular are furthermore of interest as they are strongly influenced by many-electron correlations. In such cases their theoretical description requires a more comprehensive treatment than that offered by first order perturbation theory. We apply such a treatment through the use of the CCC formalism which involves the complete numeric solution of the integral Lippmann-Schwinger equations pertaining to a particular scattering event. For laser assisted electron impact ionisation of He such a treatment is of a considerably greater accuracy than the...

  15. Physician Assistant Genomic Competencies.

    Science.gov (United States)

    Goldgar, Constance; Michaud, Ed; Park, Nguyen; Jenkins, Jean

    2016-09-01

    Genomic discoveries are increasingly being applied to the clinical care of patients. All physician assistants (PAs) need to acquire competency in genomics to provide the best possible care for patients within the scope of their practice. In this article, we present an updated version of PA genomic competencies and learning outcomes in a framework that is consistent with the current medical education guidelines and the collaborative nature of PAs in interprofessional health care teams. PMID:27490287

  16. Improving assisted living care.

    Science.gov (United States)

    Gregory, Nancy; Gesell, Sabina B; Widmer, Tom

    2007-01-01

    In the absence of a national measurement system, private vendors of satisfaction measurement and improvement services have played a crucial role in the quality movement in the assisted living industry. Survey responses from 175 resident-family dyads at 20 facilities were analyzed to identify priorities for service improvement from the customers' perspective. They include improving care provided by aides and management, meal service, and activities. Practical solutions for addressing these issues are presented.

  17. Computer-assisted psychotherapy

    OpenAIRE

    Wright, Jesse H.; Wright, Andrew S.

    1997-01-01

    The rationale for using computers in psychotherapy includes the possibility that therapeutic software could improve the efficiency of treatment and provide access for greater numbers of patients. Computers have not been able to reliably duplicate the type of dialogue typically used in clinician-administered therapy. However, computers have significant strengths that can be used to advantage in designing treatment programs. Software developed for computer-assisted therapy gen...

  18. Computer assisted mathematical programming

    OpenAIRE

    Lucas, CA; Mitra, G

    1987-01-01

    A Computer Assisted Mathematical Programming (Modelling) System (CAMPS) is described in this paper. The system uses program generator techniques for model creation and contrasts with earlier approaches which use a special purpose language to construct models. Thus no programming skill is required to formulate a model. In designing the system we have first analysed the salient components of the mathematical programming activity. A mathematical programming model is usually constructed by progre...

  19. Assistance From A Distance

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    China joins international relief efforts in Haiti with a powerful sense of mission How long does it take to ready assistance and travel some 15,000 km around the globe to provide a helping hand amid one of the worst earth-quakes in modern history? The answer might surprise you. Less than 36 hours after seismic shocks leveled much of Haiti on January

  20. [EUTHANASIA AND ASSISTED SUICIDE].

    Science.gov (United States)

    Lantero, Caroline

    2015-07-01

    Euthanasia and assisted suicide are not part of French laws of bioethics and lack, for the time being, definition and normative framework other than their criminal prosecution. To transform them into a right, these concepts certainly call for an ethical and legal debate. This paper aims to question the ideas to be considered, the conceptual bases and normative tools that may be useful to the discussion.

  1. Laparoscopic assisted cholecystostomy.

    Science.gov (United States)

    Grecu, F

    1999-01-01

    Laparoscopic assisted cholecystostomy (LAC) is a safe method for external biliary drainage in jaundiced patients with distal common bile duct obstruction. It consists of the retrieval of the fundus of the gallbladder through the trocar, thus through abdominal wall followed by suture to the skin. This technique could be an option for surgeons who manage a patients with jaundice by distal common bile duct obstruction.

  2. [EUTHANASIA AND ASSISTED SUICIDE].

    Science.gov (United States)

    Lantero, Caroline

    2015-07-01

    Euthanasia and assisted suicide are not part of French laws of bioethics and lack, for the time being, definition and normative framework other than their criminal prosecution. To transform them into a right, these concepts certainly call for an ethical and legal debate. This paper aims to question the ideas to be considered, the conceptual bases and normative tools that may be useful to the discussion. PMID:27356358

  3. Low temperature temporal and spatial atomic layer deposition of TiO{sub 2} films

    Energy Technology Data Exchange (ETDEWEB)

    Aghaee, Morteza, E-mail: m.aghaee@tue.nl; Maydannik, Philipp S. [ASTRaL Group, Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Johansson, Petri; Kuusipalo, Jurkka [Paper Converting and Packaging Technology, Tampere University of Technology, P.O. Box 541, FI-33101 Tampere (Finland); Creatore, Mariadriana [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Homola, Tomáš; Cameron, David C. [R& D Center for Low-Cost Plasma and Nanotechnology Surface Modification, Masaryk University, Kotlářská 2, 611 37 Brno (Czech Republic)

    2015-07-15

    Titanium dioxide films were grown by atomic layer deposition (ALD) using titanium tetraisopropoxide as a titanium precursor and water, ozone, or oxygen plasma as coreactants. Low temperatures (80–120 °C) were used to grow moisture barrier TiO{sub 2} films on polyethylene naphthalate. The maximum growth per cycle for water, ozone, and oxygen plasma processes were 0.33, 0.12, and 0.56 Å/cycle, respectively. X-ray photoelectron spectrometry was used to evaluate the chemical composition of the layers and the origin of the carbon contamination was studied by deconvoluting carbon C1s peaks. In plasma-assisted ALD, the film properties were dependent on the energy dose supplied by the plasma. TiO{sub 2} films were also successfully deposited by using a spatial ALD (SALD) system based on the results from the temporal ALD. Similar properties were measured compared to the temporal ALD deposited TiO{sub 2}, but the deposition time could be reduced using SALD. The TiO{sub 2} films deposited by plasma-assisted ALD showed better moisture barrier properties than the layers deposited by thermal processes. Water vapor transmission rate values lower than 5 × 10{sup −4} g day{sup −1} m{sup −2} (38 °C and 90% RH) was measured for 20 nm of TiO{sub 2} film deposited by plasma-assisted ALD.

  4. Limited Deposit Insurance Coverage and Bank Competition

    OpenAIRE

    Shy, Oz; Stenbacka, Rune; Yankov, Vladimir

    2014-01-01

    Deposit insurance designs in many countries place a limit on the coverage of deposits in each bank. However, no limits are placed on the number of accounts held with different banks. Therefore, under limited deposit insurance, some consumers open accounts with different banks to achieve higher or full deposit insurance coverage. We compare three regimes of deposit insurance: No deposit insurance, unlimited deposit insurance, and limited deposit insurance. We show that limited deposit insuranc...

  5. Coating material innovation in conjunction with optimized deposition technologies

    International Nuclear Information System (INIS)

    Concentrating on physical vapour deposition methods several examples of recently developed coating materials for optical applications were studied for film deposition with optimized coating technologies: mixed evaporation materials for ion assisted deposition with modern plasma ion sources, planar metal and oxide sputter targets for Direct Current (DC) and Mid-Frequency (MF) pulsed sputter deposition and planar and rotatable sputter targets of transparent conductive oxides (TCO) for large-area sputter deposition. Films from specially designed titania based mixed evaporation materials deposited with new plasma ion sources and possible operation with pure oxygen showed extended ranges of the ratio between refractive index and structural film stress, hence there is an increased potential for the reduction of the total coating stress in High-Low alternating stacks and for coating plastics. DC and MF-pulsed sputtering of niobium metal and suboxide targets for optical coatings yielded essential benefits of the suboxide targets in a range of practical coating conditions (for absent in-situ post-oxidation ability): higher refractive index and deposition rate, better reproducibility and easier process control, and the potential for co-deposition of several targets. Technological progress in the manufacture of rotatable indium tin oxide (ITO) targets with regard to higher wall-thickness and density was shown to be reflected in higher material stock and coater up-time, economical deposition rates and stable process behaviour. Both for the rotatable ITO targets and higher-dense aluminum-doped zinc oxide (AZO) planar targets values of film transmittance and resistivity were in the range of the best values industrially achieved for films from the respective planar targets. The results for the rotatable ITO and planar AZO targets point to equally optimized process and film properties for the optimized rotatable AZO targets currently in testing

  6. Steer assistance for teleoperation

    Science.gov (United States)

    Pape, Olivier; Houbloup, Philippe; Leveque, Stephane

    2005-05-01

    Giat Industries, expert in combat system, designs and integrates the technologies (electrical network, mechanical design, ergonomic and mobility command and control) for the French military and civil robotic. One of the main problems of current robotics is to treat the lack of operator's perception due to teleoperation. The article details the assistance for the steer control part of mobility command and control. The purpose of the assistance is to secure the vehicle, to insure the continuity of the command (in particular for tracked vehicle equipped of hydrostatic steering group), and to adapt the command (to use all the range of the command even at high speed and to adapt the speed to the desired curve). The advantage of the system presented in the article is to filter the order first and to transmit to the actuators only safe orders preserving the vehicle. This approach transforms the telepilot's order watching and correction problem, to a telepilot's order filtering problem. We pass here, from a logical "a posteriori" to a logical of "a priori" processing. The assistance includes: a model of the dynamic behavior of the vehicle and an open loop, some feed forward with appropriate filters and a closed loop. The article presents the result of the command studies from time simulation to "man on the loop" simulation. This system, at present time applied to the French Observation Robot demonstrator SYRANO (developped for the DGA-French Defence Procurement Agency), is the subject of a patent.

  7. Estimation of magnetic relaxation property for CVD processed YBCO-coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Y.; Kiuchi, M.; Otabe, E.S. [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502 (Japan); Matsushita, T., E-mail: matusita@cse.kyutech.ac.j [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502 (Japan); Shikimachi, K.; Watanabe, T.; Kashima, N.; Nagaya, S. [Chubu Electric Power Co., Inc., 20-1, Kitasekiyama, Ohdaka-cho, Midori-ku, Nagoya 459-8522 (Japan)

    2010-11-01

    Ion Beam Assist Deposition/Chemical Vapor Deposition(IBAD/CVD)-processed YBCO-coated conductors with high critical current density J{sub c} at high magnetic fields are expected to be applied to superconducting equipments such as superconducting magnetic energy storage (SMES). For application to superconducting magnet in SMES one of the most important properties for superconductors is the relaxation property of superconducting current. In this paper, the relaxation property is investigated for IBAD/CVD-processed YBCO-coated conductors of the superconducting layer in the range of 0.18-0.90 {mu}m. This property can be quantitatively characterized by the apparent pinning potential, U{sub 0}*. It is found that U{sub 0}* takes a smaller value due to the two-dimensional pinning mechanism at high magnetic fields for conductor with thinner superconducting layer. Although U{sub 0}* decreases with increasing thickness at low magnetic fields at 20 K, it increases at high magnetic fields. The results are theoretically explained by the model of the flux creep and flow based on the dimensionality of flux pinning. Scaling analysis is examined for the dependence of U{sub 0}{sup *} on the magnetic field, temperature and the layer thickness.

  8. Estimation of magnetic relaxation property for CVD processed YBCO-coated conductors

    Science.gov (United States)

    Takahashi, Y.; Kiuchi, M.; Otabe, E. S.; Matsushita, T.; Shikimachi, K.; Watanabe, T.; Kashima, N.; Nagaya, S.

    2010-11-01

    Ion Beam Assist Deposition/Chemical Vapor Deposition(IBAD/CVD)-processed YBCO-coated conductors with high critical current density Jc at high magnetic fields are expected to be applied to superconducting equipments such as superconducting magnetic energy storage (SMES). For application to superconducting magnet in SMES one of the most important properties for superconductors is the relaxation property of superconducting current. In this paper, the relaxation property is investigated for IBAD/CVD-processed YBCO-coated conductors of the superconducting layer in the range of 0.18-0.90 μm. This property can be quantitatively characterized by the apparent pinning potential, U0∗. It is found that U0∗ takes a smaller value due to the two-dimensional pinning mechanism at high magnetic fields for conductor with thinner superconducting layer. Although U0∗ decreases with increasing thickness at low magnetic fields at 20 K, it increases at high magnetic fields. The results are theoretically explained by the model of the flux creep and flow based on the dimensionality of flux pinning. Scaling analysis is examined for the dependence of U0∗ on the magnetic field, temperature and the layer thickness.

  9. High efficiency turbine blade coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Youchison, Dennis L.; Gallis, Michail A.

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600 oC and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the production of layered

  10. Ultraviolet laser deposition of graphene thin films without catalytic layers

    KAUST Repository

    Sarath Kumar, S. R.

    2013-01-09

    In this letter, the formation of nanostructured graphene by ultraviolet laser ablation of a highly ordered pyrolytic graphite target under optimized conditions is demonstrated, without a catalytic layer, and a model for the growth process is proposed. Previously, graphene film deposition by low-energy laser (2.3 eV) was explained by photo-thermal models, which implied that graphene films cannot be deposited by laser energies higher than the C-C bond energy in highly ordered pyrolytic graphite (3.7 eV). Here, we show that nanostructured graphene films can in fact be deposited using ultraviolet laser (5 eV) directly over different substrates, without a catalytic layer. The formation of graphene is explained by bond-breaking assisted by photoelectronic excitation leading to formation of carbon clusters at the target and annealing out of defects at the substrate.

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

    Science.gov (United States)

    Abraham, J. W.; Strunskus, T.; Faupel, F.; Bonitz, M.

    2016-05-01

    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.

  12. Microwave-assisted atmospheric pressure plasma polymerization of hexamethyldisiloxane

    Science.gov (United States)

    Matsubayashi, Toshiki; Hidaka, Hiroki; Muguruma, Hitoshi

    2016-07-01

    Microwave-assisted atmospheric pressure plasma polymerization is presented. A system with a re-entrant microwave cavity realizes simple matching, stable plasma, and free space under the orifice of plasma steam. Hexamethyldisiloxane is employed as a monomer, while argon is used as a carrier gas. The effective area of the hydrophobic coating film used corresponds to a circle of 20 mm diameter and the deposition rate considered is 5 nm/min. Matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy shows that the coating film has a large molecular weight (>200 kDa), suggesting that a high-crosslinking and three-dimensional polymer matrix is formed and microwave-assisted atmospheric pressure plasma polymerization is fulfilled.

  13. Laser-induced ion emission during polymer deposition from a flash-frozen water ice matrix

    DEFF Research Database (Denmark)

    Rodrigo, K.; Toftmann, Bo; Schou, Jørgen;

    2004-01-01

    Flash-frozen water solutions of 1% weight PEG (polyethylene glycol) at -50 degreesC were used as targets at a laser wavelength of 355 nm for polymer deposition with Matrix-Assisted Pulsed Laser Evaporation (MAPLE). For medium laser fluences the transfer of PEG material to the substrate was accomp......Flash-frozen water solutions of 1% weight PEG (polyethylene glycol) at -50 degreesC were used as targets at a laser wavelength of 355 nm for polymer deposition with Matrix-Assisted Pulsed Laser Evaporation (MAPLE). For medium laser fluences the transfer of PEG material to the substrate...... Elsevier B.V. All rights reserved....

  14. Equine-assisted therapy

    OpenAIRE

    Barbara MacLean, LCAT, MT-BC

    2011-01-01

    Since 2008, the Samuel S. Stratton Department of Veterans Affairs (VA) Medical Center in Albany, New York, has offered the Equine-Assisted Therapy Program for veterans with posttraumatic stress disorder (PTSD). The first year, the program ran for 7 weeks, and in 2009 and 2010, we were able to run 12-week programs in the summers and a 9-week program in the fall of 2010. Also in 2010, veterans from the VA's Adaptive Sports Program enjoyed a 3-hour "sampler" afternoon. In 2011, we are holding tw...

  15. Computer - Assisted Accounting

    OpenAIRE

    SORIN-CIPRIAN TEIUŞAN

    2009-01-01

    What is computer-assisted accounting? Where is the place and what is the role of the computer in the financial-accounting activity? What is the position and importance of the computer in the accountant’s activity? All these are questions that require scientific research in order to find the answers. The paper approaches the issue of the support granted to the accountant to organize and manage the accounting activity by the computer. Starting from the notions of accounting and computer, the co...

  16. FDIC Summary of Deposits (SOD) Download File

    Data.gov (United States)

    Federal Deposit Insurance Corporation — The FDIC's Summary of Deposits (SOD) download file contains deposit data for branches and offices of all FDIC-insured institutions. The Federal Deposit Insurance...

  17. 44 CFR 206.62 - Available assistance.

    Science.gov (United States)

    2010-10-01

    ... HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Emergency Assistance § 206.62 Available... threat of a catastrophe; (b) Coordinate all disaster relief assistance (including voluntary assistance... Stafford Act; and (g) Assist State and local governments in the distribution of medicine, food, and...

  18. Dispersion engineered high-Q silicon Nitride Ring-Resonators via Atomic Layer Deposition

    CERN Document Server

    Riemensberger, Johann; Herr, Tobias; Brasch, Victor; Holzwarth, Ronald; Kippenberg, Tobias J

    2012-01-01

    We demonstrate dispersion engineering of integrated silicon nitride based ring resonators through conformal coating with hafnium dioxide deposited on top of the structures via atomic layer deposition (ALD). Both, magnitude and bandwidth of anomalous dispersion can be significantly increased. All results are confirmed by high resolution frequency-comb-assisted-diode-laser spectroscopy and are in very good agreement with the simulated modification of the mode spectrum.

  19. [Computer-assisted surgery].

    Science.gov (United States)

    Micali, Salvatore

    2011-01-01

    The broad range of Computer Assisted Surgery (CAS) represents the integration of computer technology in surgical procedures for presurgical planning, guiding or manipulation. Surgical robots and surgical endoscopic navigation are the most challenging applications to urology. A surgical robot is defined as a computer-controlled manipulator with artificial sensing which can be programmed to move, and position tools to carry out surgical tasks. In urology, robots have been tested in two areas: endourology and laparoscopy. Surgical navigation allows the surgeon to process data from pre- and intraoperative sources, aiming at purification and presentation of the most relevant information. Image-guided systems (IGS), augmented reality (AR) and navigation in endoscopic soft tissue surgery represent the three main topics of surgical urological navigation. IGS involve matching the coordinates from medical imaging (preoperative registration) with coordinates from the patient in the operating room (registration and updating images). IGS have become the standard of care in providing navigational assistance during neurosurgery, offering subsurface and functional information to the surgeon. PMID:21452161

  20. Meson assisted dibaryons

    CERN Document Server

    Gal, Avraham

    2015-01-01

    We discuss a new type of L=0 positive-parity dibaryons, pion-B-B', where the dominant binding mechanism is provided by resonating p-wave pion-baryon interactions. Recent calculations of such pion assisted dibaryons are reviewed with special emphasis placed on the non-strange I(JP)=1(2+) N-Delta dibaryon D_{12}(2150) studied recently at JLab, and on the 0(3+) Delta-Delta dibaryon D_{03}(2380) discovered recently by the WASA-at-COSY Collaboration. We review recent searches by the HADES Collaboration at GSI and by the E15 and E27 Experiments at J-PARC for a strangeness S=-1 I(JP)=1/2(0-) K-pp dibaryon and perhaps also for a strange I(JP)=3/2(2+) N-Sigma(1385) pion assisted dibaryon Y_{3/2(2+)}(2270). Charm C=+1 dibaryons, predicted with these same I(JP) values, are also briefly reviewed.

  1. Some characteristics of electrospark deposition

    Energy Technology Data Exchange (ETDEWEB)

    Lesnjak, A. [Q-Techna, Krsko (Sierra Leone); Tusek, J. [Faculty of Mechanical Engineering, Ljubljana (Sierra Leone)

    2003-11-01

    The paper deals with some characteristics of electrospark deposition. A relevant device and the process are described, the material transfer is shown schematically, and the average droplet mass, the thickness of deposited layer, and the layer roughness are determined. Two types of substrate (tool steel, austenitic stainless steel), two types of shielding gas, (Ar, He), and three types of filler material, (WC, TiC, Stellite 6) were used. With some deposit, chemical analyses of deposit surfaces were performed and with some others through-thickness chemical analyses. Among the final conclusions the most important one is that the addition of a shielding gas results in a considerable increase in deposit quality. The device manufacturer, however, recommends deposition without the addition of a shielding gas. (orig.)

  2. High rate buffer layer for IBAD MgO coated conductors

    Science.gov (United States)

    Foltyn, Stephen R.; Jia, Quanxi; Arendt, Paul N.

    2007-08-21

    Articles are provided including a base substrate having a layer of an oriented material thereon, and, a layer of hafnium oxide upon the layer of an oriented material. The layer of hafnium oxide can further include a secondary oxide such as cerium oxide, yttrium oxide, lanthanum oxide, scandium oxide, calcium oxide and magnesium oxide. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of hafnium oxide or layer of hafnium oxide and secondary oxide.

  3. Momentum Deposition in Curvilinear Coordinates

    Energy Technology Data Exchange (ETDEWEB)

    Cleveland, Mathew Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lowrie, Robert Byron [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rockefeller, Gabriel M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thompson, Kelly Glen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wollaber, Allan Benton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-03

    The momentum imparted into a material by thermal radiation deposition is an important physical process in astrophysics and inertial confinement fusion (ICF) simulations. In recent work we presented a new method of evaluating momentum deposition that relies on the combination of a time-averaged approximation and a numerical integration scheme. This approach robustly and efficiently evaluates the momentum deposition in spherical geometry. Future work will look to extend this approach to 2D cylindrical geometries.

  4. Electrophoretic Deposition of Hydroxyapatite Coating

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Hydroxyapatite (HAP) coatings were deposited onto titanium substrates by electrophoretic deposition (EPD) fromethanol. The results indicated that the addition of very small amount of HCI resulted in a decrease in the aging timeas well as the suspension concentration required to obtain a coating. In addition, the results revealed the existenceof a critical saturated voltage (Vsat), which had significant effect on the quality of deposition. The mean interfacialshear strengths of HAP coatings after sintering were found to be greater than 13 MPa.

  5. Multiphase flow wax deposition modelling

    Energy Technology Data Exchange (ETDEWEB)

    Matzain, A. [Petronas Research and Scientific Services, Kuala Lumpur (Malaysia); Zhang, H.-Q.; Volk, M.; Redus, C.L.; Brill, J.P. [University of Tulsa (United States); Apte, M.S. [Shell Technology EP (United States); Creek, J.L. [Chevron Petroleum Technology (United States)

    2000-07-01

    Results are presented from two-phase flow wax deposition tests using a state-of-the-art, high pressure, multiphase flow test facility. Wax deposition was found to be flow pattern dependent and occurs only along the pipe wall in contact with the waxy crude oil. The deposition buildup trend at low mixture velocities is similar to that observed in laminar single-phase flow tests. The buildup trend at high mixture velocities is similar to that observed in turbulent single-phase flow tests. Thinner and harder deposits at the bottom than at the top of the pipe were observed in horizontal intermittent flow tests. Thicker and harder deposits were observed at low liquid superficial velocity than at high liquid superficial velocity annular flow tests. No wax deposition was observed along the upper portion of the pipe in stratified flow tests. A semi-empirical kinetic model tailored for the wax deposition tests predicted wax thickness with an acceptable accuracy, especially at high oil superficial velocity. Deposition rate reduction due to shear stripping and rate enhancement due to entrapment of oil and other mechanisms not accounted for by the classical Fick's mass diffusion theory were incorporated through the use of dimensionless variables and empirical constants derived from the wax deposition data. The kinetic model, although semi-empirical, provides an insight for future model development. (author)

  6. Assistance to Tourism: Exploratory Estimates

    OpenAIRE

    Productivity Commission

    2005-01-01

    In April 2005, the research paper into ‘Assistance to Tourism: Exploratory Estimates’ was released. It is the first comprehensive attempt to quantify the extent of assistance to tourism on a comparable basis to that for other industries in Australia. While care is needed in interpreting the results, the estimates suggest that tourism receives a lower rate of Australian Government assistance than the average for the manufacturing and primary sectors, but more than for other service industries....

  7. Assisted closure of fasciotomy wounds

    OpenAIRE

    Fowler, J. R.; Kleiner, M. T.; Das, R.; Gaughan, J.P.; Rehman, S.

    2012-01-01

    Introduction Negative pressure wound therapy (NPWT) and vessel loop assisted closure are two common methods used to assist with the closure of fasciotomy wounds. This retrospective review compares these two methods using a primary outcome measurement of skin graft requirement. Methods A retrospective search was performed to identify patients who underwent fasciotomy at our institution. Patient demographics, location of the fasciotomy, type of assisted closure, injury characteristics, need for...

  8. Employee Assistance Program Issues

    Science.gov (United States)

    Gettleman, Alan G.; McGuire, William

    1999-01-01

    Employee Assistance Program (EAP) officers, as well as personnel in other disciplines from eight NASA Centers, attended this breakout session. Ms. Brenda Blair, MA, CEAP, a guest speaker at the conference, also attended as a consultant. Representatives from the NASA Centers introduced themselves and spoke briefly about their programs. In a discussion related to the conference theme on benchmarking, quality control issues within the EAP community and adequate documentation of cases were addressed. Disposition and provision for quality assurance checks for EAP providers in single person offices were also discussed. Ms. Blair presented methods for consulting with other NASA personnel in single person EAP offices as a quality control measure. EAP intervention in critical incidents was discussed. The question of whether EAP assistance is an asset or a potential liability in those situations was addressed. Suggestions were made of topics for future EAP video-teleconference topics. A program on EAP ethics was planned for a September video teleconference. Each person was asked to provide intake forms they use to Mr. Gettleman or Ms. Blair. Ms. Blair said she would review the forms to ensure that adequate notification is provided to the client for confidentiality. She would also review them to ensure they have adequate limits of confidentiality--a topic for future video teleconferencing. Mr. Gettleman described the NASA initiative to reduce stresses in the workplace, and the activities of an ad-hoc EAP group that will make recommendations to NASA senior management. Alternative training methods were discussed for reaching target audiences such as employees at risk, supervisors, and others. Pfc. David A. Pendleton, Victim Assistance Coordinator, U.S. Capitol Police. U.S. House of Representatives made a special presentation. Pfc. Pendleton was on duty during the tragic shooting of two Federal guards at the U.S. Capitol. He related the events immediately after the incident. He

  9. 78 FR 56583 - Deposit Insurance Regulations; Definition of Insured Deposit

    Science.gov (United States)

    2013-09-13

    ... U.S. bank under deposit agreements governed by non-U.S. law to take advantage of a large bank's... 330 Bank deposit insurance, Banks, Banking, Reporting and recordkeeping requirements, Savings and Loan... of U.S. insured depository institutions (``IDI'' or ``U.S. bank''). The Final Rule clarifies...

  10. Radiology for dental assistants

    International Nuclear Information System (INIS)

    The book provides dental assistants with the knowledge they need to apply X-rays in a safe and economical manner. Starting from the theoretical fundamentals of radiophysics, the biologic effects of X-rays leading to the protective requirements of the new X-Ray Ordinance are explained. The main topics are the adjustment rules for dental film, panorama and cassette film images which are explained in detail and illustrated, the topics of materials and equipment, and processing up to the stage of a safe guarding. In chapters dealing with the practical points of view, the applications in paedodentistry and orthodontics, in endodonty, parodontology and in imaging the temporo-mandibular joints are described; these chapters also deal with recognizing and avoiding mistakes. An appendix with data worth knowing rounds up the contents. The book is based on numerous training seminars. (orig./MG)

  11. Cell-Assisted Lipotransfer

    DEFF Research Database (Denmark)

    Toyserkani, Navid Mohamadpour; Quaade, Marlene Louise; Sørensen, Jens Ahm

    2016-01-01

    -derived stromal cells (ASCs) to enrich the fat graft, a procedure termed cell-assisted lipotransfer (CAL). The aim of this review was to systematically review the current preclinical and clinical evidence for the efficacy of CAL compared with conventional lipotransfer. MATERIALS AND METHODS: A systematic search...... was performed on PubMed and other databases to identify all preclinical and clinical studies where CAL with ASCs was compared with conventional lipotransfer. A total of 20 preclinical studies and seven clinical studies were included in the review. RESULTS: The preclinical studies consisted of 15 studies using...... immunodeficient animal models and five studies using immunocompetent studies. Seventeen studies examined weight/volume retention of which 15 studies favored CAL over conventional lipotransfer. One clinical study did not find any efficacy of CAL and the remaining six studies favored CAL. CONCLUSIONS: The present...

  12. Neutrino assisted gauge mediation

    International Nuclear Information System (INIS)

    Recent observation shows that the Higgs mass is at around 125 GeV while the prediction of the minimal supersymmetric standard model is below 120 GeV for stop mass lighter than 2 TeV unless the top squark has a maximal mixing. We consider the right-handed neutrino supermultiplets as messengers in addition to the usual gauge mediation to obtain sizeable trilinear soft parameters At needed for the maximal stop mixing. Neutrino messengers can explain the observed Higgs mass for stop mass around 1 TeV. Neutrino assistance can also generate charged lepton flavor violation including μ→e γ as a possible signature of the neutrino messengers. We consider the S4 discrete flavor model and show the relation of the charged lepton flavor violation, θ 13 of neutrino oscillation and the muon's g-2. (orig.)

  13. Direct laser deposition of nanostructured tungsten oxide for sensing applications

    Science.gov (United States)

    Palla-Papavlu, Alexandra; Filipescu, Mihaela; Schneider, Christof W.; Antohe, Stefan; Ossi, Paolo M.; Radnóczi, György; Dinescu, Maria; Wokaun, Alexander; Lippert, Thomas

    2016-05-01

    Nanostructured tungsten trioxide (WO3) thin films are deposited by pulsed laser deposition (PLD) and radio-frequency (RF) assisted PLD onto interdigitated sensor structures. Structural characterization by x-ray diffraction and Raman spectroscopy shows the WO3 films are polycrystalline, with a pure monoclinic phase for the PLD grown films. The as-fabricated WO3 sensors are tested for ammonia (NH3) detection, by measuring the electrical response to NH3 at different temperatures. Sensors based on WO3 deposited by RF-PLD do not show any response to NH3. In contrast, sensors fabricated by PLD operating at 100 °C and 200 °C show a slow recovery time whilst at 300 °C, these sensors are highly sensitive in the low ppm range with a recovery time in the range of a few seconds. The microstructure of the films is suggested to explain their excellent electrical response. Columnar WO3 thin films are obtained by both deposition methods. However, the WO3 films grown by PLD are porous, (which may allow NH3 molecules to diffuse through the film) whereas RF-PLD films are dense. Our results highlight that WO3 thin films deposited by PLD can be applied for the fabrication of gas sensors with a performance level required for industrial applications.

  14. Enhanced nitrogen deposition over China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xuejun; Zhang, Ying; Han, Wenxuan; Tang, Aohan; Shen, Jianlin; Cui, Zhenling; Christie, Peter; Zhang, Fusuo [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Vitousek, Peter [Department of Biology, Stanford University, Stanford, California 94305 (United States); Erisman, Jan Willem [VU University Amsterdam, 1081 HV Amsterdam (Netherlands); Goulding, Keith [The Sustainable Soils and Grassland Systems Department, Rothamsted Research, Harpenden AL5 2JQ (United Kingdom); Fangmeier, Andreas [Institute of Landscape and Plant Ecology, University of Hohenheim, 70593 Stuttgart (Germany)

    2013-02-28

    China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P < 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures. Nitrogen from ammonium (NH4+) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3-), in agreement with decreased ratios of NH3 to NOx emissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment.

  15. Second-generation HTS conductors

    CERN Document Server

    2010-01-01

    The discovery of high temperature superconductors (HTS) in 1986 by two IBM scientists led to an unprecedented explosion of research and development efforts world-wide because of the significant potential for practical applications offered by these materials. However, the early euphoria created by the exciting prospects was dampened by the daunting task of fabricating these materials into useful forms with acceptable superconducting properties. Progress towards this goal has been hindered by many intrinsic materials problems, such as weak-links, flux-creep, and poor mechanical properties. The above problems led to the development of the Second-Generation of HTS wires. Three methods were invented to produce flexible metallic substrates, which were also crystallographically biaxially textured, and resembled a long, mosaic single crystal. The first method invented is the Ion-Beam-Assisted-Deposition (IBAD). The second method developed was the Inclined-Substrate-Deposition (ISD). The third method invented is calle...

  16. Compartment-specific aggregases direct distinct nuclear and cytoplasmic aggregate deposition

    DEFF Research Database (Denmark)

    Miller, Stephanie Bm; Ho, Chi-Ting; Winkler, Juliane;

    2015-01-01

    42 (cytosolic), direct protein deposition to nuclear INQ and cytosolic (CytoQ) sites, respectively. Intriguingly, Btn2 is transiently induced by both protein folding stress and DNA replication stress, with DNA surveillance proteins accumulating at INQ. Our data therefore reveal a bipartite, inter...... quality control compartment, INQ, for the deposition of both nuclear and cytosolic misfolded proteins, irrespective of ubiquitination. Deposition of misfolded cytosolic proteins at INQ involves chaperone-assisted nuclear import via nuclear pores. The compartment-specific aggregases, Btn2 (nuclear) and Hsp...

  17. Deposition and Resuspension of Particles

    DEFF Research Database (Denmark)

    Lengweiler, P.; Nielsen, Peter V.; Moser, A.;

    A new experimental set-up to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airBorne dust concentration considerably. As a basis for developing methods to eliminate dust related problems in rooms, there is a...

  18. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    World-class sandstone-type uranium deposits are defined as epigenetic concentrations of uranium minerals occurring as uneven impregnations and minor massive replacements primarily in fluvial, lacustrine, and deltaic sandstone formations. The main purpose of this introductory paper is to define, classify, and introduce to the general geologic setting for sandstone-type uranium deposits

  19. Liquefier Dynamics in Fused Deposition

    DEFF Research Database (Denmark)

    Bellini, Anna; Guceri, Selcuk; Bertoldi, Maurizio

    2004-01-01

    Layered manufacturing (LM) is an evolution of rapid prototyping (RP) technology whereby a part is built in layers. Fused deposition modeling (FDM) is a particular LM technique in which each section is fabricated through vector style deposition of building blocks, called roads, which...

  20. Variable temperature semiconductor film deposition

    Science.gov (United States)

    Li, Xiaonan; Sheldon, Peter

    1998-01-01

    A method of depositing a semiconductor material on a substrate. The method sequentially comprises (a) providing the semiconductor material in a depositable state such as a vapor for deposition on the substrate; (b) depositing the semiconductor material on the substrate while heating the substrate to a first temperature sufficient to cause the semiconductor material to form a first film layer having a first grain size; (c) continually depositing the semiconductor material on the substrate while cooling the substrate to a second temperature sufficient to cause the semiconductor material to form a second film layer deposited on the first film layer and having a second grain size smaller than the first grain size; and (d) raising the substrate temperature, while either continuing or not continuing to deposit semiconductor material to form a third film layer, to thereby anneal the film layers into a single layer having favorable efficiency characteristics in photovoltaic applications. A preferred semiconductor material is cadmium telluride deposited on a glass/tin oxide substrate already having thereon a film layer of cadmium sulfide.

  1. Big moving day for biodiversity? A macroecological assessment of the scope for assisted colonization as a conservation strategy under global warming

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Fløjgaard, Camilla; Morueta-Holme, Naia;

    2009-01-01

    . However, we also emphasize that other, more traditional conservation strategies should also be strengthened, notably providing more space for nature and reducing nitrogen deposition to increase population resilience and facilitate unassisted colonization. Furthermore, any implementation of assisted...

  2. Ni-Co laterite deposits

    Science.gov (United States)

    Marsh, Erin E.; Anderson, Eric D.

    2011-01-01

    Nickel-cobalt (Ni-Co) laterite deposits are an important source of nickel (Ni). Currently, there is a decline in magmatic Ni-bearing sulfide lode deposit resources. New efforts to develop an alternative source of Ni, particularly with improved metallurgy processes, make the Ni-Co laterites an important exploration target in anticipation of the future demand for Ni. This deposit model provides a general description of the geology and mineralogy of Ni-Co laterite deposits, and contains discussion of the influences of climate, geomorphology (relief), drainage, tectonism, structure, and protolith on the development of favorable weathering profiles. This model of Ni-Co laterite deposits represents part of the U.S. Geological Survey Mineral Resources Program's effort to update the existing models to be used for an upcoming national mineral resource assessment.

  3. Enhanced nitrogen deposition over China.

    Science.gov (United States)

    Liu, Xuejun; Zhang, Ying; Han, Wenxuan; Tang, Aohan; Shen, Jianlin; Cui, Zhenling; Vitousek, Peter; Erisman, Jan Willem; Goulding, Keith; Christie, Peter; Fangmeier, Andreas; Zhang, Fusuo

    2013-02-28

    China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P effects on human health and the environment.

  4. Assistive Technology and Mathematics Education

    Science.gov (United States)

    Akpan, Joseph P.; Beard, Lawrence A.

    2014-01-01

    Educators and caregivers now have the opportunity to individualize and differentiate instructions with many technological devices never before available. Assistive Technology is being introduced in the classroom at all levels as a tool for teachers to help deliver instruction to all students. Assistive Technology is widely used to ensure…

  5. The Ethics of Assisted Suicide.

    Science.gov (United States)

    Callahan, Jay

    1994-01-01

    From social work perspective, considers ethics of assisted suicide. Discusses traditional social work value of client self-determination and identifies tensions in this ideal and conflicts with value of client well-being. Finds assisted suicide unethical, arguing that studies have shown judgment of most suicidal people to be impaired as result of…

  6. Trapping and diffusion of noble gas atoms in some off-stoichiometric ceramics studied by thermal desorption spectrometry. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Hoondert, W.H.B.

    1993-01-01

    The thesis deals with the mobility of small noble gas atoms, mainly helium, in ceramic materials with high defect concentrations. Hence, two subjects are covered: diffusion and defect physics. The experimental technique employed is Thermal Desorption Spectrometry (TDS). An introductory outline of TDS is given. The present study was initiated for various reasons. First of all, research on helium retention and mobility behavior, such as bubble nucleation and subsequent bubble migration, in potential fusion reactor wall materials (which some of the ceramics are) is of practical interest. Secondly, because the ceramic materials investigated in the present work have defect concentrations on the order of percents, and because they are binary compounds where in principle more defect types can be present than in pure materials, the defect physics is more complicated and diverse than e.g., in simple metals. Finally, high defective materials can serve as a model system for thin films produced by Ion Beam Assisted Deposition (IBAD). TDS as an analytical tool is of key importance to be able to control the IBAD process, and for the understanding of the atomic-scale phenomena involved.

  7. Comparison of biological characteristics of mesenchymal stem cells grown on two different titanium implant surfaces

    International Nuclear Information System (INIS)

    This study examined the biological characteristics of mesenchymal stem cells (MSCs) grown on sand-blasted, large-grit, acid-etched (SLA) surface and hydroxyapatite (HA) coating on the SLA (HA/SLA) surface of titanium dental implants. The HA/SLA surfaces of titanium dental implants were formed by the ion beam assisted deposition (IBAD) method. Rabbit bone marrow derived mesenchymal stem cells cultured in vitro were seeded onto the surface of SLA and HA/SLA; the growth states of MSCs on the two samples were observed by a scanning electron microscope; the proliferation index, alkaline phosphatase (ALP) activity, osteocalcin (OCN) content of MSCs and mRNA relative expression level of osteopontin (opn) were compared between two groups. MSCs were found to be easier to adhere to the HA/SLA surface compared to the SLA surface. At the same time, the ALP activity and the OCN content of MSCs grown on the HA/SLA surface were obviously higher, and the relative expression level of opn mRNA was 4.78 times higher than that on the SLA surface. The HA coating formed by the IBAD method on the SLA surface of titanium dental implants significantly improves proliferation and well-differentiated osteoblastic phenotype of MSCs, which indicates a promising method for the surface modification of titanium dental implants

  8. The future for physician assistants.

    Science.gov (United States)

    Cawley, J F; Ott, J E; DeAtley, C A

    1983-06-01

    Physician assistants were intended to be assistants to primary care physicians. Physicians in private practice have only moderately responded to the availability of these professionals. Cutbacks in the numbers of foreign medical graduates entering American schools for graduate medical education, concern for overcrowding in some specialties, and the economic and clinical capabilities of physician assistants have lead to new uses for these persons. Physician assistants are employed in surgery and surgical subspecialties; in practice settings in institutions such as medical, pediatric, and surgical house staff; and in geriatric facilities, occupational medicine clinics, emergency rooms, and prison health systems. The projected surplus of physicians by 1990 may affect the use of physician assistants by private physicians in primary care.

  9. Glacial atmospheric phosphorus deposition

    Science.gov (United States)

    Kjær, Helle Astrid; Dallmayr, Remi; Gabrieli, Jacopo; Goto-Azuma, Kumiko; Hirabayashi, Motohiro; Svensson, Anders; Vallelonga, Paul

    2016-04-01

    Phosphorus in the atmosphere is poorly studied and thus not much is known about atmospheric phosphorus and phosphate transport and deposition changes over time, though it is well known that phosphorus can be a source of long-range nutrient transport, e.g. Saharan dust transported to the tropical forests of Brazil. In glacial times it has been speculated that transport of phosphorus from exposed shelves would increase the ocean productivity by wash out. However whether the exposed shelf would also increase the atmospheric load to more remote places has not been investigated. Polar ice cores offer a unique opportunity to study the atmospheric transport of aerosols on various timescales, from glacial-interglacial periods to recent anthropogenic influences. We have for the first time determined the atmospheric transport of phosphorus to the Arctic by means of ice core analysis. Both total and dissolved reactive phosphorus were measured to investigate current and past atmospheric transport of phosphorus to the Arctic. Results show that glacial cold stadials had increased atmospheric total phosphorus mass loads of 70 times higher than in the past century, while DRP was only increased by a factor of 14. In the recent period we find evidence of a phosphorus increase over the past 50 yrs in ice cores close to human occupation likely correlated to forest fires. References: Kjær, Helle Astrid, et al. "Continuous flow analysis method for determination of dissolved reactive phosphorus in ice cores." Environmental science & technology 47.21 (2013): 12325-12332. Kjær, Helle Astrid, et al. "Greenland ice cores constrain glacial atmospheric fluxes of phosphorus." Journal of Geophysical Research: Atmospheres120.20 (2015).

  10. TULSA UNIVERSITY PARAFFIN DEPOSITION PROJECTS

    Energy Technology Data Exchange (ETDEWEB)

    Michael Volk; Cem Sarica

    2003-10-01

    As oil and gas production moves to deeper and colder water, subsea multiphase production systems become critical for economic feasibility. It will also become increasingly imperative to adequately identify the conditions for paraffin precipitation and predict paraffin deposition rates to optimize the design and operation of these multiphase production systems. Although several oil companies have paraffin deposition predictive capabilities for single-phase oil flow, these predictive capabilities are not suitable for the multiphase flow conditions encountered in most flowlines and wellbores. For deepwater applications in the Gulf of Mexico, it is likely that multiphase production streams consisting of crude oil, produced water and gas will be transported in a single multiphase pipeline to minimize capital cost and complexity at the mudline. Existing single-phase (crude oil) paraffin deposition predictive tools are clearly inadequate to accurately design these pipelines because they do not account for the second and third phases, namely, produced water and gas. The objective of this program is to utilize the current test facilities at The University of Tulsa, as well as member company expertise, to accomplish the following: enhance our understanding of paraffin deposition in single and two-phase (gas-oil) flows; conduct focused experiments to better understand various aspects of deposition physics; and, utilize knowledge gained from experimental modeling studies to enhance the computer programs developed in the previous JIP for predicting paraffin deposition in single and two-phase flow environments. These refined computer models will then be tested against field data from member company pipelines. The following deliverables are scheduled during the first three projects of the program: (1) Single-Phase Studies, with three different black oils, which will yield an enhanced computer code for predicting paraffin deposition in deepwater and surface pipelines. (2) Two

  11. Evaluation of HEXORR Tone Assistance Mode Against Spring Assistance.

    Science.gov (United States)

    Godfrey, Sasha Blue; Holley, Rahsaan J; Lum, Peter S

    2015-07-01

    Robots are a promising tool for rehabilitation, and research suggests combining assistance with subject participation to maintain motivation and engagement. In this study, we compare two different types of robotic assistance for hand rehabilitation: Tone, a novel method designed to directly compensate for the user's hypertonia, and Spring, a commonly used method simulating a spring-like force attracting the subject to the target position. Eight chronic stroke subjects played a Gate Game, where they guide a ball through a sweeping, on-screen gate. Each subject was exposed to 5 modes: unassisted, assisted by the Spring and Tone modes, and "delay" modes where the assistance was provided after a period without assistance. Compared to unassisted trials, subjects produced less positive work and more negative work with all types of assistance but also reached a larger ROM and scored higher on the game. Notably, subjects produced more positive work overall with Tone compared to Spring. Further, subjects produced positive work over a significantly shorter range with Spring compared to Unassisted, while there was no difference between Tone and Unassisted. While both modes were effective at enabling the training of a larger workspace, these results suggest Tone assistance maintains a greater level of subject engagement and participation, likely making it a useful tool for hand rehabilitation. PMID:25667355

  12. High laser-fluence deposition of organic materials in water ice matrices by ''MAPLE''

    DEFF Research Database (Denmark)

    Christensen, Bo Toftmann; Rodrigo, K.; Schou, Jørgen;

    2005-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) is a deposition technique for organic material. Water ice was used as a matrix for the biotechnologically important guest material, polyethylene glycol (PEG), for concentrations from 0.5 to 4 wt.%. The target was irradiated with 6 ns laser pulses...... B.V. All rights reserved....

  13. Robotically assisted gynaecological surgery.

    Science.gov (United States)

    Falcone, Tommaso; Steiner, Charles P

    2002-05-01

    Industry has used robots successfully for fine, delicate, repetitive tasks for decades. Recently, robots have been introduced into clinical medicine and specifically into the surgical suite. Voice algorithms have been developed that allow voice activation of some types of equipment in the operating room, such as the laparoscope or the light source. Advances in computer software have allowed a computer controller to translate a surgeon's movements from the handles located in a console to the robotic arms that hold the surgical instruments. This console is placed away from the surgical table. Clinical experience is limited and there are few published clinical trials. The initial trials have focused on laparoscopic microsuturing such as that performed during coronary bypass surgery or tubal anastomosis. Preliminary results have demonstrated that laparoscopic coronary bypass surgery with the internal mammary artery can be achieved. In gynaecological surgery, laparoscopic tubal reanastomosis can be performed using the same technique that has been used traditionally at laparotomy. Future clinical trials will assess whether other gynaecological procedures can be performed with robotic assistance. PMID:12082211

  14. Computer Assisted Audit Techniques

    Directory of Open Access Journals (Sweden)

    Eugenia Iancu

    2007-01-01

    Full Text Available From the modern point of view, audit takes intoaccount especially the information systems representingmainly the examination performed by a professional asregards the manner for developing an activity by means ofcomparing it to the quality criteria specific to this activity.Having as reference point this very general definition ofauditing, it must be emphasized that the best known segmentof auditing is the financial audit that had a parallel evolutionto the accountancy one.The present day phase of developing the financial audithas as main trait the internationalization of the accountantprofessional. World wide there are multinational companiesthat offer services in the financial auditing, taxing andconsultancy domain. The auditors, natural persons and auditcompanies, take part at the works of the national andinternational authorities for setting out norms in theaccountancy and auditing domain.The computer assisted audit techniques can be classified inseveral manners according to the approaches used by theauditor. The most well-known techniques are comprised inthe following categories: testing data techniques, integratedtest, parallel simulation, revising the program logics,programs developed upon request, generalized auditsoftware, utility programs and expert systems.

  15. Thermally assisted MRAM

    Energy Technology Data Exchange (ETDEWEB)

    Prejbeanu, I L [Spintec, URA 2512 CEA/CNRS, CEA-Grenoble, 17 r. des Martyrs, 38054 Grenoble Cedex 9 (France); Kerekes, M [Spintec, URA 2512 CEA/CNRS, CEA-Grenoble, 17 r. des Martyrs, 38054 Grenoble Cedex 9 (France); Sousa, R C [Spintec, URA 2512 CEA/CNRS, CEA-Grenoble, 17 r. des Martyrs, 38054 Grenoble Cedex 9 (France); Sibuet, H [LIMN, DRT/Leti/DIHS, CEA-Grenoble, 17 r. des Martyrs, 38054 Grenoble Cedex 9 (France); Redon, O [LIMN, DRT/Leti/DIHS, CEA-Grenoble, 17 r. des Martyrs, 38054 Grenoble Cedex 9 (France); Dieny, B [Spintec, URA 2512 CEA/CNRS, CEA-Grenoble, 17 r. des Martyrs, 38054 Grenoble Cedex 9 (France); Nozieres, J P [Crocus Technology, 5 Place Robert Schumann, BP 1510, 38025 Grenoble Cedex 1 (France)

    2007-04-23

    Magnetic random access memories (MRAMs) are a new non-volatile memory technology trying establish itself as a mainstream technology. MRAM cell operation using a thermally assisted writing scheme (TA-MRAM) is described in this review as well as its main design challenges. This approach is compared to conventional MRAM, highlighting the improvements in write selectivity, power consumption and thermal stability. The TA-MRAM writing was tested and validated in the dynamic regime down to 500 ps write pulses. The heating process was investigated for the influence of the voltage pulse width, junction area and lead volume looking at the required write power density. The possibilities to control and reduce the write power density are described. The most promising solution to optimize the heating process and reduce the power consumption is to insert two thermal barrier layers at both ends of the MTJ layer stack, between the junction and the electrical leads, using low thermal conductivity materials. This minimizes the heating losses and improves the heating efficiency.

  16. Plasma Deposition of Amorphous Silicon

    Science.gov (United States)

    Calcote, H. F.

    1982-01-01

    Strongly adhering films of silicon are deposited directly on such materials as Pyrex and Vycor (or equivalent materials) and aluminum by a non-equilibrium plasma jet. Amorphous silicon films are formed by decomposition of silicon tetrachloride or trichlorosilane in the plasma. Plasma-jet technique can also be used to deposit an adherent silicon film on aluminum from silane and to dope such films with phosphorus. Ability to deposit silicon films on such readily available, inexpensive substrates could eventually lead to lower cost photovoltaic cells.

  17. Acid Deposition Maps in Spain

    International Nuclear Information System (INIS)

    Animal and monthly deposition velocity and total sulfur deposition maps have been performed for the peninsular Spain for 1992 by using the inferential method. To do this, updated databases with high space and time resolution, for land uses (CORINE) and meteorological information from analysis modelling for the same year, have been utilized. The final result are deposition maps in a 5x5 Km2 grid which allow to assess the methodology used in Europe to obtain the maps of excedances over the critical loads of pollutants. (Author) 32 refs

  18. Particle deposition in ventilation ducts

    Energy Technology Data Exchange (ETDEWEB)

    Sippola, Mark R.

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 {micro}m were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on

  19. Wind assistance: A requirement for migration of shorebirds?

    Science.gov (United States)

    Butler, R.W.; Williams, T.D.; Warnock, N.; Bishop, M.A.

    1997-01-01

    We investigated the importance of wind-assisted flight for northward (spring) migration by Western Sandpipers (Calidris mauri) along the Pacific Coast of North America. Using current models of energy costs of flight and recent data on the phenology of migration, we estimated the energy (fat) requirements for migration in calm winds and with wind-assisted flight for different rates of fat deposition: (1) a variable rate, assuming that birds deposit the minimum amount of fat required to reach the next stopover site; (2) a constant maximum rate of 1.0 g/day; and (3) a lower constant rate of 0.4 g/day. We tested these models by comparing conservative estimates of predicted body mass along the migration route with empirical data on body mass of Western Sandpipers at different stopover sites and upon arrival at the breeding grounds. In calm conditions, birds would have to deposit unrealistically high amounts of fat (up to 330% of observed values) to maintain body mass above absolute lean mass values. Fat-deposition rates of 1.0 g/day and 0.4 g/day, in calm conditions, resulted in a steady decline in body mass along the migration route, with predicted body masses on arrival in Alaska of only 60% (13.6 g) and 26% (5.9 g) of average lean mass (22.7 g). Conversely, birds migrating with wind assistance would be able to complete migration with fat-deposition rates as low as 0.4 g/day, similar to values reported for this size bird from field studies. Our results extend the conclusion of the importance of winds for large, long-distance migrants to a small, short-distance migrant. We suggest that the migratory decisions of birds are more strongly influenced by the frequency and duration of winds aloft, i.e. by events during the flight phase, than by events during the stopover phase of migration, such as fat-deposition rate, that have been the focus of much recent migration theory.

  20. Surface morphology of thin lysozyme films produced by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Pryds, Nini;

    2007-01-01

    Thin films of the protein, lysozyme, have been deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Frozen targets of 0.3-1.0 wt.% lysozyme dissolved in ultrapure water were irradiated by laser light at 355 mn with a fluence of 2 J/cm(2). The surface quality of the thin...

  1. Development of mechanical brake assist; Mechanical brake assist no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, M.; Shingyoji, S.; Nakamura, I.; Tagawa, T.; Saito, Y.; Ishihara, T.; Kobayashi, S.; Yoshida, M. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    We have recognized that there are drivers who cannot apply strong brake pedal force , in spite of the necessity of hard braking in emergencies. We have developed a `mechanical brake assist system` which assists drivers appropriately, according to the drivers` characteristics based on studying the characteristic`s of conditions of drivers applying the brake pedal force in emergency conditions. 2 refs., 7 figs., 1 tab.

  2. Cathodoluminescence in Quaternary carbonate deposits

    Science.gov (United States)

    Braithwaite, Colin J. R.

    2016-05-01

    The cathodoluminescent oscillatory and sectoral growth zones common in crystals formed in ancient limestone successions in a variety of putative environments appear to be rare or absent from Recent and Pleistocene marine carbonate sequences. The factors controlling cathodoluminescence and reasons for this disparity are examined. The cathodoluminescent zones in the cements of ancient rocks have been interpreted as responses to variations in the redox potential of formative pore waters during crystal growth; although similar cathodoluminescent behaviour is recorded from some deposits, including travertines and Quaternary speleothems, formed in what are thought to have been strongly oxidizing environments. The apparent absence of cathodoluminescence in the most Recent and Pleistocene marine deposits, that presumably reflect deposition and diagenesis in environments that are also characteristically oxidized, therefore seems anomalous. The controlling influences on cathodoluminescence are reviewed, together with evidence relating to observations of Pleistocene marine deposits and likely conditions of formation but, where it is present, the mechanism(s) for its development remain elusive.

  3. Hereditary iron and copper deposition

    DEFF Research Database (Denmark)

    Aaseth, Jan; Flaten, Trond Peder; Andersen, Ole

    2007-01-01

    Hereditary deposition of iron (primary haemochromatosis) or copper (Wilson's disease) are autosomal recessive metabolic disease characterized by progressive liver pathology and subsequent involvement of various other organs. The prevalence of primary haemochromatosis is approximately 0.5%, about...

  4. Assisted hatching in assisted reproduction: a state of the art.

    Science.gov (United States)

    Hammadeh, Mohamad Eid; Fischer-Hammadeh, Constanze; Ali, Khaled Refaat

    2011-02-01

    The World Health Organization estimates that one in six couples experience some delay in conception and an increasing number require treatment by the assisted conception (AC) procedures of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI).The implantation rate of embryos resulting from in vitro fertilization cycles is generally less than 20%. The exposure of oocytes and embryos to the artificial conditions of in vitro culture may have negative effects on the embryo's ability to undergo normal hatching, resulting in low rates of implantation following IVF and embryo transfer. Human embryos resulting from superovulation develop more slowly in vitro compared to embryos in vivo, manifest a relatively high degree of cytogenetic abnormalities and undergo cellular fragmentation. Artificially disrupting the zona pellucida is known as assisted hatching (AH) and there is some evidence that embryos that have undergone zona manipulation for assisted hatching tend to implant one day earlier than unhatched embryos. A variety of techniques have since been employed to assist embryo hatching, including partial mechanical zona dissection, zona drilling and zona thinning, making use of acid tyrodes, proteinases, piezon vibrator manipulators and lasers. This review will consider the impact of IVF conditions on zona pellucida physiology, zona hardening, different techniques of assisted hatching, who may benefit from assisted hatching and potential hazards.

  5. Laser deposition of sulfonated phthalocyanines for gas sensors

    Energy Technology Data Exchange (ETDEWEB)

    Fitl, Premysl, E-mail: fitlp@vscht.cz [Department of Physics and Measurements, Institute of Chemical Technology Prague, Technicka 5, Prague 6 CZ-166 28 (Czech Republic); Department of Analysis of Functional Materials, Institute of Physics AS CR v.v.i, Na Slovance 1999/2, Prague 8 CZ-182 21 (Czech Republic); Vrnata, Martin; Kopecky, Dusan; Vlcek, Jan; Skodova, Jitka [Department of Physics and Measurements, Institute of Chemical Technology Prague, Technicka 5, Prague 6 CZ-166 28 (Czech Republic); Bulir, Jiri; Novotny, Michal; Pokorny, Petr [Department of Analysis of Functional Materials, Institute of Physics AS CR v.v.i, Na Slovance 1999/2, Prague 8 CZ-182 21 (Czech Republic)

    2014-05-01

    Thin layers of nickel and copper tetrasulfonated phthalocyanines (NiPcTS and CuPcTS) were prepared by Matrix Assisted Pulsed Laser Evaporation method. The depositions were carried out with KrF excimer laser (energy density of laser radiation E{sub L} = 0.1–0.5 J cm{sup −2}) from dimethylsulfoxide matrix. For both materials the ablation threshold E{sub L-th} was determined. The following properties of deposited layers were characterized: (a) chemical composition (FTIR spectra); (b) morphology (SEM and AFM portraits); and (c) impedance of gas sensors based on NiPcTS and CuPcTS layers in the presence of two analytes – hydrogen and ozone. The prepared sensors exhibit response to 1000 ppm of hydrogen and 100 ppb of ozone even at laboratory temperature.

  6. Monte Carlo Simulation of Diamond Deposition at Low Temperature

    Institute of Scientific and Technical Information of China (English)

    董丽芳; 张玉红

    2001-01-01

    Diamond deposition at low temperatures is investigated and the relationship between substrate temperature for diamond growth and the energy of the carbonaceous species is given. The electron energy distribution and velocity distribution during the electron assisted chemical vapour deposition have been obtained by using Monte Carlo simulation. The main results obtained are as follows. (1) The substrate temperature for diamond growth will be lower than 800 C when the carbonaceous species on the substrate have mobility energy. For example, if the energy of the carbonaceous species is 0. 75 eV, the substrate temperature will be 380℃-600℃. (2) The greatnumber of atomic H on the substrate is of importance to the growth of diamond films.

  7. Stress in ion-beam assisted silicon dioxide and tantalum pentoxide thin films

    CERN Document Server

    Sirotkina, N

    2003-01-01

    Ta sub 2 O sub 5 and SiO sub 2 thin films, deposited at room temperature by ion-beam sputtering (IBS) and dual ion-beam sputtering (DIBS), and SiO sub 2 films, deposited by reactive e-beam evaporation and ion-assisted deposition, were studied. The energy (150-600 eV) and ion-to-atom arrival ratio (0.27-2.0) of assisting argon and oxygen ions were varied. Influence of deposition conditions (deposition system geometry, nature and amount of gas in the chamber, substrate cleaning and ion-assistance parameters) on films properties (stress, composition, refractive index n sub 5 sub 0 sub 0 sub n sub m and extinction coefficient k sub 5 sub 0 sub 0 sub n sub m) was investigated. A scanning method, based on substrate curvature measurements by laser reflection and stress calculation using the Stoney equation, was employed. RBS showed that stoichiometric Ta sub 2 O sub 5 films contain impurities of Ar, Fe and Mo. Stoichiometric SiO sub 2 films also contain Ta impurity. Argon content increases with ion bombardment and, ...

  8. Electrospark deposition for die repair

    Directory of Open Access Journals (Sweden)

    J. Tušek

    2012-01-01

    Full Text Available The electrospark deposition is a process for surfacing of hard metal alloys, e.g. carbides and stellites, on the surfaces of new or old machine elements. In this process, a high current is conducted through an oscillating electrode and a substrate for a very short period of time. In the paper, the process is described and the thickness of deposited layer, chemical composition, dilution rate and the layer roughness are determined.

  9. Uranium deposits in volcanic rocks

    International Nuclear Information System (INIS)

    Twenty-eight papers were presented at the meeting and two additional papers were provided. Three panels were organized to consider the specific aspects of the genesis of uranium deposits in volcanic rocks, recognition criteria for the characterization of such deposits, and approaches to exploration. The papers presented and the findings of the panels are included in the Proceedings. Separate abstracts were prepared for each of these papers

  10. Vapor deposition of hardened niobium

    Science.gov (United States)

    Blocher, Jr., John M.; Veigel, Neil D.; Landrigan, Richard B.

    1983-04-19

    A method of coating ceramic nuclear fuel particles containing a major amount of an actinide ceramic in which the particles are placed in a fluidized bed maintained at ca. 800.degree. to ca. 900.degree. C., and niobium pentachloride vapor and carbon tetrachloride vapor are led into the bed, whereby niobium metal is deposited on the particles and carbon is deposited interstitially within the niobium. Coating apparatus used in the method is also disclosed.

  11. The Cognitive Onboard Operator Assistant Architecture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a cognitively inspired architecture for deploying an automated intelligent onboard operator assistant. This assistant facilitates the onboard control...

  12. Daily Public Assistance Grants Award Activity

    Data.gov (United States)

    Department of Homeland Security — Daily activity of Public Assistance Grant Awards, including FEMA Region, State, Disaster Declaration Number, Event description, Mission Assigned agency, Assistance...

  13. 38 CFR 21.3020 - Educational assistance.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Survivors' and Dependents' Educational Assistance Under... definition contained in § 21.3021. (b) 45 months limitation. Educational assistance may not exceed a...

  14. Synergy Between Plasma-Assisted ALD and Roll-to-Roll Atmospheric Pressure PE-CVD Processing of Moisture Barrier Films on Polymers

    NARCIS (Netherlands)

    Starostin, S. A.; Keuning, W.; Schalken, J.; Creatore, M.; Kessels, W. M. M.; Bouwstra, J. B.; van de Sanden, M. C. M.; de Vries, H. W.

    2016-01-01

    The synergy between fast (1600 nm · min−1), roll-to-roll plasma-enhanced chemical vapor deposited (PE-CVD) SiO2 layers and plasma-assisted atomic layer deposited (PA-ALD) ultra-thin Al2O3 films has been investigated in terms of moisture permeation barrier properties. The effective and intrinsic wate

  15. 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.

  16. Robot-Assisted Gynecologic Surgery

    Science.gov (United States)

    ... guys tonight. We’re going to be talking robotic-assisted gynecologic surgery, and I can tell you, ... and it shows us how we start a robotic case really like standard laparoscopy, and there’s an ...

  17. Robot-Assisted Gynecologic Surgery

    Medline Plus

    Full Text Available Halifax Health Presents: Roboti-Assisted Gynecologic Surgery Halifax Health Florida September 27, 2011 Hello, and welcome to another live ... you by the fine folks here at Halifax Health. Broadcasting live from sunny Daytona Beach, Florida, and ...

  18. Multifamily Assistance Section 8 Contracts

    Data.gov (United States)

    Department of Housing and Urban Development — he information regarding the Multifamily Assistance and Section 8 contracts, and properties is being furnished for the convenience of interested parties. The...

  19. FEMA Housing Assistance Renters - API

    Data.gov (United States)

    Department of Homeland Security — This dataset lists aggregated, non-PII dataset of FEMA Housing Assistance Program for House Renters The data was generated by FEMA's ECIM (Enterprise Coordination...

  20. Temporary Assistance for Needy Families

    Data.gov (United States)

    U.S. Department of Health & Human Services — This is the FY2009 Work Participation Rate data for the Temporary Assistance for Needy Families (TANF) Program. It provides state-by-state data on Work...

  1. Radiological Assistance Program (RAP) Regions

    Data.gov (United States)

    Department of Homeland Security — The U.S. Department of Energy (DOE) created the Radiological Assistance Program (RAP) in the 1950s to make DOE resources and expertise available to organizations...

  2. Fault Management Assistant (FMA) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — S&K Aerospace (SKA) proposes to develop the Fault Management Assistant (FMA) to aid project managers and fault management engineers in developing better and...

  3. FEMA Housing Assistance Owners - API

    Data.gov (United States)

    Department of Homeland Security — This dataset lists aggregated, non-PII dataset of FEMA Housing Assistance Program for House Owners The data was generated by FEMA's ECIM (Enterprise Coordination...

  4. Robot-Assisted Gynecologic Surgery

    Medline Plus

    Full Text Available ... Broadcasting live from sunny Daytona Beach, Florida, and I am your host, Dr. Scott Klioze. We’ve ... to be talking robotic-assisted gynecologic surgery, and I can tell you, we have got a lot ...

  5. S-Chip Technical Assistance

    Data.gov (United States)

    U.S. Department of Health & Human Services — The page will provide access to reports and other published products designed to assist states with complicated S-Chip technical issues. The reports and products...

  6. Laboratory aspects of assisted reproduction.

    OpenAIRE

    Yeung, WS; Ng, EH

    2000-01-01

    A number of advances have been made concerning the laboratory aspects of assisted reproduction. Intracytoplasmic sperm injection has revolutionised the treatment of male infertility. With the development of better embryo culture media, blastocyst transfer is now possible and is likely to reduce high-order multiple pregnancy in assisted reproduction treatment. Pre-implantation genetic diagnosis has become an alternative to prenatal diagnosis. The recent use of molecular biology techniques to d...

  7. FOOD ASSISTANCE LANDSCAPE MARCH 2006

    OpenAIRE

    Anonymous

    2006-01-01

    One in five Americans participates in at least one of USDA's food and nutrition assistance programs during the year. In fiscal 2005, an estimated 55 percent of USDA's budget supported the programs that provide children and low-income people with access to food, a healthful diet, and nutrition education. The Economic Research Service (ERS) is responsible for conducting studies and evaluations of USDA's food assistance programs. This report uses preliminary data from USDA's Food and Nutrition S...

  8. Ion-assisted doping of CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Fahrenbruch, A.L.; Chien, K.F.; Kim, D.; Lopez-Otero, A.; Sharps, P.; Bube, R.H. (Dept. of Materials Science and Engineering, Stanford Univ., CA (USA))

    1989-10-15

    The possibility of using ion-assisted doping during growth of p-CdTe films for solar cells has been investigated, to obtain higher doping densities than previously obtained with conventional film deposition processes. For the first time, controlled doping has been demonstrated with low-energy phosphorus ions to obtain hole densities of up to 2 x 10{sup 17} cm{sup -3} in homoepitaxial films deposited by vacuum evaporation on single-crystal CdTe. Solar cells made with these films suggest that ion damage reduces the diffusion length in the most highly doped films and that the active region of such cells must be made with considerably lower doping densities. For polycrystalline films on alumina, preliminary results indicate that the hole densities obtained are not sufficient to overcome grain boundary barrier limited conductivity. (orig.).

  9. Laser assisted removal of fixed contamination from metallic substrate

    International Nuclear Information System (INIS)

    A single mode pulsed fiber laser was used to remove fixed contamination from stainless steel substrate by ablation. Samples were simulated by electro-deposition technique with 232U as the test contaminant. Laser power, repetition rate, laser beam scanning speed and number of passes were optimised to obtain the desired ablation depth in the substrate. Ablation depth varying between few microns to few hundreds of microns could be achieved through careful control of these processing parameters. The absence of any activity in laser treated samples provided experimental signature of the efficacy of the laser assisted removal of fixed contamination. (author)

  10. Nanostructured polymer stable glasses via matrix assisted pulsed laser evaporation

    Science.gov (United States)

    Shepard, Kimberly B.

    Amorphous materials, or glasses, which lack a crystalline structure, are technologically ubiquitous with applications including structural components, pharmaceuticals, and electronic devices. Glasses are traditionally formed by rapid cooling from the melt state, where molecules become kinetically trapped into a non-equilibrium configuration. The temperature at which the material transforms from supercooled liquid to glass is the glass transition temperature. The glass transition temperature is the most important property of amorphous materials, as it determines the range of temperatures where they are fabricated, used and stored. Recent technological developments in which glasses are formed by alternative routes, such as physical vapor deposition and matrix assisted pulsed laser evaporation (MAPLE), enable tunability of Tg and related physical properties. High-Tg glasses formed by these techniques are termed "stable glasses" and exhibit a wide range of exceptional properties. This work focuses on the formation and characterization of stable polymer glasses fabricated via MAPLE. Bulk films (>1 microm thick) of glassy polymers fabricated by MAPLE at slow growth rates (polymer glasses. Building on molecular dynamics simulations from the literature on the MAPLE process, we experimentally study the origin of nanostructure in our MAPLE-deposited films. We measure the time-of-flight of MAPLE-deposited material, confirming that the velocity is sufficiently low for intact deposition of polymer nanoglobules. The size distribution of polymer nanoglobules fabricated in short MAPLE depositions provides insight into how nanostructured MAPLE films form. Using our atomic force microscopy-based nanoscale dilatometry technique, we directly probe the nanoscale thermal behavior of individual polymer nanoglobules. We confirm that bulk and nanoscale glasses share many of the same physical behavior: enhanced stability above the glass transition temperature, and ~40% excess volume. We

  11. Tissue cell assisted fabrication of tubular catalytic platinum microengines

    Science.gov (United States)

    Wang, Hong; Moo, James Guo Sheng; Pumera, Martin

    2014-09-01

    We report a facile platform for mass production of robust self-propelled tubular microengines. Tissue cells extracted from fruits of banana and apple, Musa acuminata and Malus domestica, are used as the support on which a thin platinum film is deposited by means of physical vapor deposition. Upon sonication of the cells/Pt-coated substrate in water, microscrolls of highly uniform sizes are spontaneously formed. Tubular microengines fabricated with the fruit cell assisted method exhibit a fast motion of ~100 bodylengths per s (~1 mm s-1). An extremely simple and affordable platform for mass production of the micromotors is crucial for the envisioned swarms of thousands and millions of autonomous micromotors performing biomedical and environmental remediation tasks.We report a facile platform for mass production of robust self-propelled tubular microengines. Tissue cells extracted from fruits of banana and apple, Musa acuminata and Malus domestica, are used as the support on which a thin platinum film is deposited by means of physical vapor deposition. Upon sonication of the cells/Pt-coated substrate in water, microscrolls of highly uniform sizes are spontaneously formed. Tubular microengines fabricated with the fruit cell assisted method exhibit a fast motion of ~100 bodylengths per s (~1 mm s-1). An extremely simple and affordable platform for mass production of the micromotors is crucial for the envisioned swarms of thousands and millions of autonomous micromotors performing biomedical and environmental remediation tasks. Electronic supplementary information (ESI) available: Related video. See DOI: 10.1039/c4nr03720k

  12. Layered double hydroxides/polymer thin films grown by matrix assisted pulsed laser evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Birjega, R.; Matei, A.; Mitu, B.; Ionita, M.D.; Filipescu, M.; Stokker-Cheregi, F.; Luculescu, C.; Dinescu, M. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Str., 77125 Bucharest–Magurele (Romania); Zavoianu, R.; Pavel, O.D. [University of Bucharest, Faculty of Chemistry, Department of Chemical Technology and Catalysis, 4-12 Regina Elisabeta Bd., Bucharest (Romania); Corobea, M.C. [National R. and S. Institute for Chemistry and Petrochemistry, ICECHIM, 202 Splaiul Independentei Str., CP-35-274, 060021, Bucharest (Romania)

    2013-09-30

    Due to their highly tunable properties, layered double hydroxides (LDHs) are an emerging class of the favorably layered crystals used for the preparation of multifunctional polymer/layered crystal nanocomposites. In contrast to cationic clay materials with negatively charge layers, LDHs are the only host lattices with positively charged layers (brucite-like), with interlayer exchangeable anions and intercalated water. In this work, the deposition of thin films of Mg and Al based LDH/polymers nanocomposites by laser techniques is reported. Matrix assisted pulsed laser evaporation was the method used for thin films deposition. The Mg–Al LDHs capability to act as a host for polymers and to produce hybrid LDH/polymer films has been investigated. Polyethylene glycol with different molecular mass compositions and ethylene glycol were used as polymers. The structure and surface morphology of the deposited LDH/polymers films were examined by X-ray diffraction, Fourier transform infra-red spectroscopy, atomic force microscopy and scanning electron microscopy. - Highlights: • Hybrid composites deposited by matrix assisted pulsed laser evaporation (MAPLE). • Mg–Al layered double hydroxides (LDH) and polyethylene glycol (PEG) are used. • Mixtures of PEG1450 and LDH were deposited by MAPLE. • Deposited thin films preserve the properties of the starting material. • The film wettability can be controlled by the amount of PEG.

  13. The Structure and Properties of Inductively Coupled Plasma Assisted Magnetron Sputtered Nanocrystalline NbN Coatings in Corrosion Protective Die Casting Molds.

    Science.gov (United States)

    Chun, Sung-Yong

    2016-02-01

    Niobium nitride coatings for the surface modified die casting molds with various ICP powers have been prepared using ICP assisted magnetron sputtering. The applied ICP power was varied from 0 to 200 W. The deposited coatings were characterized post-deposition using X-ray diffractometry (XRD) and atomic force microscopy (AFM). Single NbN phased coatings with nano-grain sized (hardness of each coating were evaluated from potentiostat and nanoindentator. Superior corrosion protective coatings in excess of 13.9 GPa were deposited with assistance of ICP plasma during sputtering.

  14. 44 CFR 300.3 - Financial assistance.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Financial assistance. 300.3... HOMELAND SECURITY PREPAREDNESS DISASTER PREPAREDNESS ASSISTANCE § 300.3 Financial assistance. (a) The... responsibilities for IFG, crisis counseling, mass care or other functional responsibilities; (7) Training for...

  15. 44 CFR 206.161 - Relocation assistance.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Other Individual Assistance... eligible for any kind of replacement housing payment under the Uniform Relocation Assistance and Real... his being unable, because of a major disaster as determined by the President, to meet the...

  16. 34 CFR 300.105 - Assistive technology.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Assistive technology. 300.105 Section 300.105 Education... DISABILITIES State Eligibility Other Fape Requirements § 300.105 Assistive technology. (a) Each public agency must ensure that assistive technology devices or assistive technology services, or both, as those...

  17. 12 CFR 19.170 - Discovery depositions.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Discovery depositions. 19.170 Section 19.170... PROCEDURE Discovery Depositions and Subpoenas § 19.170 Discovery depositions. (a) General rule. In any... deposition of an expert, or of a person, including another party, who has direct knowledge of matters...

  18. A Radon Progeny Deposition Model

    CERN Document Server

    Guiseppe, V E; Hime, A; Rielage, K; Westerdale, S

    2011-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly Rn-222) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of Pb-210 on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to depos...

  19. [Calcium pyrophosphate dihydrate deposition disease].

    Science.gov (United States)

    Koitschev, C; Kaiserling, E; Koitschev, A

    2003-08-01

    Calcium pyrophosphate dihydrate deposition disease (CPPD) of the temporomandibular joint is rare. The disorder is characterized by the presence of crystal deposits within the affected joint. The deposition of crystals in adjacent soft tissue may lead to the formation of pseudotumors. This form of the disease is called tophaceous pseudogout and typically affects the temporomandibular joint. It is difficult to differentiate the disease, particularly from malignant tumors, on the clinical and radiographic findings alone. The diagnosis is based on histological identification of the calcium pyrophosphate crystals. We present an unusually advanced case of tophaceous pseudogout of the temporomandibular joint. The etiology, clinical and diagnostic criteria as well as treatment options are discussed on the basis of our own experience and a review of the literature. PMID:12942180

  20. Sub-aerial tailings deposition

    International Nuclear Information System (INIS)

    The sub-aerial technique involves the systematic deposition of tailings in thin layers and allowing each layer to settle, drain and partially air dry prior to covering with a further layer. Underdrainage produces densities in excess of those achieved by sub-aqueous deposition and any air-drying serves to preconsolidate each layer with a resulting further increase in density. The low permeability of the tailings surface resulting from this deposition technique results in high runoff coefficients and, by decanting the runoff component of direct precipitation, a net evaporation condition can be achieved even in high rainfall areas. An underdrainage system prevents the build-up of excess pore-pressures within the tailings mass and at decommissioning the tailings are fully consolidated and drained thereby eliminating the possibility of any long term seepage. This paper presents a general description of these design concepts, and details of two projects where the concepts have been applied